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We report a case where neuromonitoring, using motor evoked potentials (MEP), detected an intraoperative L5 nerve root deficit during a lumbosacral decompression and instrumented fusion procedure. Critically, the MEP changes were not preceded nor accompanied by any significant spontaneous electromyography (sEMG) activity. Presumptive L5 innervated muscles, including tibialis anterior (TA), extensor hallucis longus (EHL) and gluteus maximus, were targets for nerve root surveillance using combined MEP and sEMG techniques. During a high-grade spondylolisthesis correction procedure, attempts to align a left-sided rod resulted in repeated loss and recovery cycles of MEP from the TA and EHL. No accompanying EMG alerts were associated with any of the MEP changes nor were MEP variations seen from muscles innervated above and below L5. After several attempts, the rod alignment was achieved, but significant MEP signal decrement (72% decrease) remained from the EHL. Postoperatively, the patient experienced significant foot drop on the left side that recovered over a period of 3 months. This case contributes to a growing body of evidence that exclusive reliance on sEMG for spinal nerve root scrutiny can be unreliable and MEP may provide more dependable data on nerve root patency. [ABSTRACT FROM AUTHOR]

Study Design: A total of 6 formalin-fixed cadavers were included in the cadaver feasibility study.Objective: The aim was to ascertain the anatomical feasibility of extradural contralateral C7 ventral root transfer technique by cervical posterior.Summary Of Background Data: Upper limb spastic hemiplegia is a common sequela after stroke. In our previous study, the authors established a method by transferring contralateral C7 dorsal and ventral roots to the corresponding C7 dorsal and ventral roots on the affected side in the cervical posterior.Methods: In the present study, six formalin-fixed cadavers were dissected to confirm the anatomical feasibility. Experimental anastomosis in cadavers was conducted. The pertinent lengths of the extradural nerve roots were measured. The tissue structures surrounding regions between the extradural CC7 nerve roots and the vertebral artery were observed. The cervical magnetic resonance imaging scans of 60 adults were used to measure the distance between the donor and recipient nerves.Results: Experimental anastomosis showed that the distance between the donor and recipient nerves was approximately 1 cm; the short segment of the sural nerve needed bridging. The distance between both exit sites of the exit of the extradural dura mater was 33.57±1.55 mm. The length of the extradural CC7 ventral root was 22.00±0.98 mm. The ventral distance (vd) and the dorsal distance (dd) in males were 23.98±1.72 mm and 30.85±2.22 mm ( P <0.05), while those in females were 23.28±1.51 mm and 30.03±2.16 mm, respectively. C7 vertebral transverse process, ligaments, and other soft tissues were observed between the vertebral artery and the extradural C7 nerve root.Conclusion: Under the premise of less trauma, our study shows that the extradural contralateral C7 ventral root transfer technique, in theory, yields better surgical results, including better recovery of motor function and complete preservation of sensory function.Level Of Evidence: 5. [ABSTRACT FROM AUTHOR]

Study Design: Eight cadavers were included in this anatomical study.Objective: This study aimed to confirm the anatomical feasibility of extradural transfer of the contralateral T11 ventral root (VR) to the ipsilateral L2 level and the contralateral L1 VR to the ipsilateral L3 level to restore lower limb function in cases of paraplegia.Summary Of Background Data: Motor dysfunction due to hemiplegia significantly affects the daily life of patients. To date, unlike in cases of upper limb dysfunction, there are few studies on the surgical management of lower limb movement dysfunction.Materials and Methods: Eight cadavers were included in this study to confirm the feasibility of the nerve transfer. After separating the VR and dorsal root at each level, the VRs at the T11 and L1 levels were anastomosed with the VRs of L2 and L3, respectively. The length of the VRs of donor roots and the distance between the donor and recipient nerves were measured. H&E staining was performed to verify the number of axons and the cross-sectional area of the VRs. Lumbar x-rays of 60 healthy adults were used to measure the distance between the donor and recipient nerves.Results: After exposing the bilateral extradural each root, the VRs could be easily isolated from the whole root. The distance between the VRs of T11 and L2, L1, and L3 was significantly longer than the length of the donor nerve. Therefore, the sural nerve was used for grafting. The measurements performed on the lumbar x-rays of the 60 healthy adults confirmed the results. The number of axons and cross-sectional area of the VRs were measured.Conclusion: Our study confirmed the anatomical feasibility of transferring the VRs of T11 to L2 and that of L1 to L3 to restore lower limb function in cases of hemiplegia.Level Of Evidence: 5. [ABSTRACT FROM AUTHOR]

Background Spinal cord herniation into a traumatic pseudomeningocele is a rare clinical entity. We present the sixth known case and describe surgical management. Case Presentation A 44-year-old male presented with Brown-Sequard syndrome three decades after a cervical nerve root avulsion injury. Imaging revealed hemicord herniation into a C7/T1 pseudomeningocele in addition to extra-axial cord compression from further pseudomeningoceles. Significant clinical improvement was achieved following surgical repair. The radiological findings and technique for operative repair are described. Conclusion The case highlights this rare pathology and presentation, describes the surgical measures for repair of cord herniation, and provides evidence for the favorable outcome that can be achieved by surgical intervention. [ABSTRACT FROM AUTHOR]

Background Context: Total removal of spinal schwannomas is ideal but it sometimes requires tumor-involved root resection, which increases the risk of postoperative motor deterioration (PMD). Therefore, it is important for clinicians to predict the impact of tumor-involved root resection on motor function in spinal schwannomas.Purpose: To investigate the role of intraoperative electromyographic (EMG) techniques in decision-making of tumor-involved root resection for treating spinal schwannomas.Study Design: A retrospective analysis PATIENT SAMPLE: Sixty-eight patients with spinal schwannomas arising from C5-T1 or L3-S1 roots underwent total resection of schwannoma, including tumoral root.Outcome Measures: Nerve root activation threshold, free-running EMG signals, visual analogue scale, and American Spinal Injury Association scale.Methods: During evoked EMG, nerve root activation threshold for tumoral root stimulation was recorded from muscles anatomically corresponding to tumoral root. During free-running EMG, abnormal EMG signals were identified as irregularly recurrent, monomorphic signals, low frequency (<5 Hz) or absent discharges recorded from muscles innervated by tumoral root. Clinical assessments were performed before, 3 to 5 day's and six months' after operation.Results: Sixteen (16 of 68, 23.5%) patients showed PMD, and muscle strength improved or was not affected in the other 52 patients. Absent myogenic responses were observed in 19 patients with non-PMD, and nerve root activation threshold in non-PMD group was higher than that in PMD group (p<.05). Receiver operating characteristic curve revealed that cut-off value of nerve root activation threshold for distinguishing functional and nonfunctional roots was 11.8 mA. A larger number of patients without PMD than with PMD showed abnormal free-running EMG signals (p<.05). At postoperative 6-months' follow-up, ten patients with muscle weakness after tumor-involved root resection showed functional recovery (full vs. partial recovery: 5 vs. 5), and intraoperative nerve root activation threshold in these patients was higher than that in the other patients without functional recovery (p<.05). Furthermore, there is negative relationship between the duration for full recovery and nerve root activation threshold (p<.05).Conclusions: Both evoked and free-running EMG can be used as supplementary tests for differentiating functional and nonfunctional tumoral roots in spinal schwannomas, and nerve root activation threshold may be also related to prognosis of patients with muscle weakness caused by tumor-involved root resection. Therefore, intraoperative EMG techniques may provide additional references in decision-making of tumor-involved root resection. [ABSTRACT FROM AUTHOR]

Introduction: The technique of radiofrequency neurotomy (RFN) of the facet joints has been used for decades to treat persistent low back pain to good effect in carefully selected patients. Traditionally, the target is the medial branches of the dorsal root supplying the facet joint. An alternative denervation target is the facet joint capsule. Capsule‐targeting techniques may spare the multifidus muscle, a possible unintended target of traditional RFN that is thought to be important in recovering from low back pain, and have shown promising results. Methods: A modified RFN technique that targets the capsule and spares the multifidus (multifidus‐sparing RFN) is described here, along with a brief report of its application in patients with symptomatic facet joint low back pain as compared to traditional medial branch RFN (MBRF). Results: Over a 2‐year period, a total of 401 initial multifidus‐sparing RFN and 94 initial MBRF procedures were performed on patients attending a multidisciplinary pain clinic. The proportion of repeat procedures was similar: 28.4% of multifidus‐sparing procedures and 23.4% of MBRF procedures. The median repeat interval was 12 months for both groups and interquartile range was 10 months (8–18 months) for multifidus‐sparing RFN and 4 months (11–15 months) for MBRF. Effectiveness and safety profiles appear to be similar, although limited, retrospective outcome information prevented robust analysis. Conclusion: Multifidus‐sparing RFN represents an intriguing technique to denervate the facet joint pain generator while maintaining normal multifidus function. Further study is warranted, particularly in order to identify the appropriate patient criteria and long‐term outcomes. [ABSTRACT FROM AUTHOR]

Background: Cervical selective nerve root blocks (C‐SNRBs) maintain utility for presurgical planning in patients with cervical radiculopathy. Traditional fluoroscopic or stationary computed tomography (CT)‐guided methods have been associated with complications, including catastrophic neurologic insults, while ultrasound guidance has been investigated based on its theoretical advantages. Maximizing patient safety by obtaining superior anatomic and procedural details promotes the exploration for better alternative guidance. Methods: We describe a novel approach of posterolateral (PL) extraforaminal (EF) C4 SNRB using cone beam–based CT (CBCT)/fluoroscopy, which was performed on 3 separate occasions for 1 patient with suspected right C4 radiculopathy for presurgical evaluation. CBCT/fluoroscopy uniquely provides the function of both CT and fluoroscopy using a C‐arm machine. It allows precise 3‐dimensional needle planning and sophisticated 2‐dimensional needle guidance, while ensuring tight needle control and detailed monitoring of contrast spread. Results: A successful right C4 SNRB was repeatedly achieved, as evidenced by postprocedural paresthesias over the C4 dermatomal distribution and periradicular contrast spread. Additionally, the patient reported symptomatic relief (with regard to pain scores and neck range of motion), leading to cancelation of his surgical plan. Conclusion: We propose the PL‐EF approach as the safest protocol for C‐SNRBs. When compared with fluoroscopy or CT, CBCT/fluoroscopy is an advanced imaging system that provides superior anatomic neurovascular detail, while offering precise needle control, contrast media monitoring, and easy operation in an office setting. These advanced features support it as the ideal guidance method for maximizing both the safety and efficiency of the PL‐EF C‐SNRB approach. However, the claimed advantages cannot be concluded without increasing its accessibility to pain specialists and conducting a prospective study with a large sample size. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to assess the eff ectiveness of micro-vascular decompression (MVD) with or without partial sensory rhizotomy (PSR) in the treatment of trigeminal neuralgia which is refractory to medical and functional treatments. Materials and methods: Fifty-eight patients who were dia gnosed with classical trigeminal neuralgia and underwent posterior fossa decompression surgery from 2010 to 2016 by the same surgeon were included in the study. There were two groups of patients, according to operation type, with 30 (51.7%) patients treated with MVD and 28 (48.2%) treated with MVD + PSR. Records were analysed retrospectively for intraoperative fi ndings, pain intensity scores, recurrence of pain, postoperative results and complications. Results: In the early postoperative period, immediate pain relief was similar between the groups. The recurrence rate 36 months after surgery in the MVD and MVD + PSR groups was 23.3 and 7.1%, respectively. The pain-free survival time in the MVD group was 31.83 ± 1.9 (95% CI: 28.3–35.63) months, which was shorter than the 35.14 ± 1.1 (95% CI: 32.81–37.48) months in the MVD + PSR group at 36 months after surgery (P = 0.086). Concerning postoperative complications, one patient had an acute subdural haemorrhage (1.7%) and another had facial paralysis (1.7%), while hypoesthesia was experienced in 18 (31%) patients. There were no deaths in either group. Conclusion: MVD and MVD + PSR are safe and effective procedures for classical trigeminal neuralgia. [ABSTRACT FROM AUTHOR]

Background and Introduction: Patients with brachial plexus avulsion (BPA) injuries often suffer from chronic disabling drug refractory neuropathic pain. Dorsal root entry zone (DREZ) lesioning is currently the most effective surgical procedure for this intractable brachial neuralgia following BPA.Objective: To demonstrate a novel technique of "Micro-scissor DREZotomy" developed at our institution.Procedure: A 55-year-old gentleman underwent right cervical microscissor DREZotomy for post BPA neuralgia. Exclusive use of microscissors along the posterolateral sulcus, causing mechanical disruption of the nociceptive pathways through sharp dissection, results in precise lesioning with excellent pain free outcomes.Results: The patient had complete relief of the pain and uneventful recovery following the surgery and remains to be pain free at 1 year follow up.Conclusion: Microscissor DREZotomy is a simple cost-effective technique. It can easily be performed in the peripheral centers with limited resources and is a safe and effective technique in experienced hands. [ABSTRACT FROM AUTHOR]

Background. Sympathetic sprouting in the dorsal root ganglion (DRG) following nerve injuries had been proved to induce adult neuropathic pain. However, it is unclear whether the abnormal sprouting occurs in infant nerve injury. Methods. L5 spinal nerve ligation (SNL) or sham surgery was performed on adult rats and 10-day-old pups, and mechanical thresholds and heat hyperalgesia were analyzed on 3, 7, 14, 28, and 56 postoperative days. Tyrosine hydroxylase-labeled sympathetic fibers were observed at each time point, and 2 neurotrophin receptors (p75NTR and TrkA) were identified to explore the mechanisms of sympathetic sprouting. Results. Adult rats rapidly developed mechanical and heat hyperalgesia from postoperative day 3, with concurrent sympathetic sprouting in DRG. In contrast, the pup rats did not show a significantly lower mechanical threshold until postoperative day 28, at which time the sympathetic sprouting became evident in the DRG. No heat hyperalgesia was presented in pup rats at any time point. There was a late expression of glial p75NTR in DRG of pups from postoperative day 28, which was parallel to the occurrence of sympathetic sprouting. The expression of TrkA did not show such a postoperative syncing change. Conclusion. The delayed-onset mechanical allodynia in the infant nerve lesion was accompanied with parallel sympathetic sprouting in DRG. The late parallel expression of glial p75NTR injury may play an essential role in this process, which provides novel insight into the treatment of delayed adolescent neuropathic pain. [ABSTRACT FROM AUTHOR]

Study Design: Anatomic study in nine fresh-frozen cadavers.Objective: To confirm the anatomical feasibility of transferring the extradural ventral roots (VRs) and dorsal roots (DRs) of contralateral C7 nerves to those of the ipsilateral C7 nerves respectively through a cervical posterior approach.Summary Of Background Data: The contralateral C7 nerve root transfer technique makes breakthrough for treating spastic limb paralysis. However, its limitations include large surgical trauma and limited indications.Methods: Nine fresh-frozen cadavers (four females and five males) were placed prone, and the feasibility of exposing the bilateral extradural C7 nerve roots, separation of the extradural C7 VR and DR, and transfer of the VR and DR of the contralateral C7 to those of the ipsilateral C7 on the dural mater were assessed. The pertinent distances and the myelography results of each specimen were analyzed. The acetylcholinesterase (AChE) and antineurofilament 200 (NF200) double immunofluorescent staining were preformed to determine the nerve fiber properties.Results: A cervical posterior midline approach was made and the laminectomy was performed to expose the bilateral extradural C7 nerve roots. After the extradural C7 VR and DR are separated, the VR and DR of the contralateral C7 have sufficient lengths to be transferred to those of the ipsilateral C7 on the dural mater. The myelography results showed that the spinal cord is not compressed after the nerve anastomosis. The AChE and NF200 double immunofluorescent staining showed the distal ends of the contralateral C7 VRs were mostly motor nerve fibers, and the distal ends of the contralateral C7 DRs were mostly sensory nerve fibers.Conclusion: Extradural contralateral C7 nerve root transfer in a cervical posterior approach for treating spastic limb paralysis is anatomically feasible.Level Of Evidence: 5. [ABSTRACT FROM AUTHOR]

Study Design: Prospective cohort study.Objective: The aims of this study were to evaluate the outcome of surgical and nonsurgical treatment for patients with lumbar herniated disc (LHD) or lumbar spinal stenosis (LSS) after 2 years and to identify predictors for nonsuccess.Summary Of Background Data: Studies regarding the clinician's ability to identify patients with a poor prognosis are not in concurrence and further studies are warranted.Methods: This study included 390 patients with LHD or LSS referred for surgical evaluation after unsuccessful conservative treatment. Nonsuccess was defined as a Roland-Morris Disability score above 4 (0-23) or a Numeric Rating Scale back and leg pain score above 20 (0-60). Uni- and multivariate logistic regression analyses were used to investigate potential predictive factors including sociodemographic characteristics, history findings, levels of pain and disability, and magnetic resonance imaging findings.Results: Rates of nonsuccess at 2 years were approximately 30% in surgically treated patients with LHD, approximately about 60% in patients with LSS for disability, and 30% and 40%, respectively for pain. For the main outcome variable, disability, in the final multiple logistic regression model, nonsuccess after surgery was associated with male sex (odds ratio [OR] 2.04, 95% confidence interval [CI]: 1.02-4.11, P = 0.04), low level of education (OR 2.60, 95% CI: 1.28-5.29, P = 0.01), high pain intensity (OR 3.06, 95% CI: 1.51-6.21, P < 0.01), and widespread pain (OR 3.59, 95% CI: 1.36-9.46, P = 0.01).Conclusion: The results indicate that the prognosis for patients referred for surgery with persistent LHD or LSS and unsuccessful conservative treatment is substantially better when surgery is performed as opposed to not performed. The predictive value of the variables male sex, low level of education, high pain intensity, and widespread pain location found in our study are partly in accordance with results of previous studies. Thus, our results warrant further investigation until firm conclusions can be made.Level Of Evidence: 3. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective case series.Objective: Anterior sacral meningocele (ASM) is a rare disorder. We reviewed 11 cases of congenital ASM and classified them into three types based on the anatomy and relationship between the cyst and sacral nerve roots.Summary Of Background Data: The cohort with ASM is relatively large; the classification is novel and has not been previously reported.Methods: Eleven consecutive patients with ASM who underwent surgery between February 2014 and January 2019 were retrospectively analyzed. They included four males and seven females. The dorsal transsacral approach was adopted in all cases. The follow-up time was at least 3 months.Results: We attempted to classify ASM into three types. Of the 11 cases, six were caudal type, two were paraneural type, and three were nerve-root type. The meningocele was ligated after exploring no nerve involvement, in Type I and II. For Type III, the herniating sac and involved nerve roots were ligated when the nerve roots were indicated as nonfunctional on neurophysiological monitoring; otherwise, the sacral nerve roots were protected and imbricated on the residual sac like a hand-in-glove, and sutured to reconstruct the nerves sleeve. Eight cases were accompanied by tethered cord syndrome (TCS); spinal cord detethering was done with one-stage operation. Ten patients' presenting symptoms improved at 3 to 6 months' follow-up; notably, constipation significantly improved. Only one case accompanied by an epidermoid cyst had a second laparoscopic surgery by a general surgeon.Conclusion: Aim of surgical treatment is to obliterate the communication between the subarachnoid space and herniated sac, detether the spinal cord, and resect the congenital tumor. The new classification helps to recognize the relationship between the meningocele and sacral nerve roots, and subsequently adopt different surgical strategies. We consider the dorsal transsacral approach relatively feasible, safe, and with lower complication.Level Of Evidence: 4. [ABSTRACT FROM AUTHOR]

An editorial is presented on the Evolution of Radiofrequency Denervation for Pain Indications. The article discusses that this study demonstrated both efficacy and exceptional long-term clinical outcomes in individuals with chronic neck pain due to whiplash injury; and the introduction and optimization of genicular nerve RFA for the treatment of chronic knee pain followed a similar path of development in the 2010–2020 decade.

Background Context: Both open surgical resection (OSR) and radiofrequency ablation (RFA) have been reported for spinal osteoid osteoma (OO).Purpose: To verify the clinical safety and efficiency of RFA with OSR in treating spinal OO.Study Design: Retrospective cohort study.Patient Sample: Twenty-eight consecutive patients with spinal OO who underwent either RFA or OSR in our institute between September 2006 and December 2016.Outcome Measures: The age, gender, lesion distribution, surgical time, estimated blood loss, complications, local recurrence, visual analogue scale (VAS), and the modified Frankel grade were documented.Methods: We retrospectively reviewed 28 patients with spinal OO who had been treated in our hospital from September 2006 to December 2016. Patients were followed at 3, 6, 12, and 24 months after the index surgery. The minimum follow-up period was 12 months. This study was funded by Peking University Third Hospital (Y71508-01) (¥ 400,000).Results: Twelve and 16 patients were treated with CT-guided percutaneous RFA and OSR, respectively. Spinal OO locations were cervical in 4, thoracic in 4, lumbar in 3, and sacral vertebra in 1 in the RFA group and cervical in 12, thoracic in 1, and lumber in 3 in the OSR group. RFA showed shorter operating time, less blood loss, and less in-hospital stay than open surgery [105.0 ± 33.8 minutes vs. 186.4 ± 53.5 minutes (p < .001), 1 (0 to 5) ml vs. 125 (30-1200) ml (p < .001) and 1 (1-3) days vs. 6 (3-10) days (p < .001), respectively]. At last follow-up, one patient underwent a secondary RFA for recurrence. VAS improvement was 7.5 (3-10) and 6.5 (4-9) (p = .945) in the RFA and OSR groups, respectively. The overall complication rate was 8.3% (1/12) and 18.8% (3/16) in the RFA and OSR groups, respectively.Conclusions: If there is sufficient cerebrospinal fluid between the spinal OO lesion and spinal cord/nerve root (more than 1 mm), RFA is effective and safe for treatment of well-selected spinal OO, showing reduced operating time, blood loss, in-hospital stay, and complications compared to OSR. However, OSR is still recommended in cases with spinal cord/nerve root compression. [ABSTRACT FROM AUTHOR]

Cebranopadol (trans-6'-fluoro-4',9'-dihydro-N,N-dimethyl-4-phenyl-spiro[cyclohexane-1,1'(3'H)-pyrano[3,4-b]indol]-4-amine) is a novel analgesic nociceptin/orphanin FQ opioid peptide (NOP) and classical opioid receptor (MOP, DOP, and KOP) agonist with highly efficacious and potent activity in a broad range of rodent models of nociceptive, inflammatory, and neuropathic pain as well as limited opioid-type side effects such as respiratory depression. This study was designed to explore contribution and interaction of NOP and classical opioid receptor agonist components to cebranopadol analgesia in the rat spinal nerve ligation (SNL) model. Assessing antihypersensitive activity in SNL rats intraperitoneal (IP) administration of cebranopadol resulted in ED50 values of 3.3 and 3.58 μg/kg in two independent experiments. Pretreatment (IP) with J-113397 (4.64 mg/kg) a selective antagonist for the NOP receptor or naloxone (1 mg/kg), naltrindole (10 mg/kg), or nor-BNI (10 mg/kg), selective antagonists for MOP, DOP, and KOP receptors, yielded ED50 values of 14.1, 16.9, 17.3, and 15 μg/kg, respectively. This 4-5 fold rightward shift of the dose-response curves suggested agonistic contribution of all four receptors to the analgesic activity of cebranopadol. Combined pretreatment with a mixture of the antagonists for the three classical opioid receptors resulted in an 18-fold potency shift with an ED50 of 65.5 μg/kg. The concept of dose equivalence was used to calculate the expected additive effects of the parent compound for NOP and opioid receptor contribution and to compare them with the observed effects, respectively. This analysis revealed a statistically significant difference between the expected additive and the observed effects suggesting intrinsic synergistic analgesic interaction of the NOP and the classical opioid receptor components of cebranopadol. Together with the observation of limited respiratory depression in rats and humans the synergistic interaction of NOP and classical opioid receptor components in analgesia described in the current study may contribute to the favorable therapeutic index of cebranopadol observed in clinical trials. [ABSTRACT FROM AUTHOR]

Background: The iatrogenic injuries to the lumbar nerves during the fixation the sacroiliac (SI) joint fractures with anterior plates were often reported. No specific method had been reported to avoid it. This study was done to find a safer way of placing the anterior plates and screws for treating the sacroiliac (SI) joint fracture and/or dislocation.Methods: The research was performed using 8 male and 7 female normal corpse pelvic specimens preserved by 10% formalin solution. Try by measuring the horizontal distance from L4, L5 nerve roots to the sacroiliac joint and perpendicular distance from L4, L5 nerve roots to the ala sacralis, the length of L4, L5 nerve roots from intervertebral foramen to the edge of true pelvis, the diameter of L4, L5 nerve roots. The angles between the sacroiliac joint and sagittal plane were measured on the CT images.Results: The horizontal distance between the lateral side of the anterior branches of L4, L5 nerve roots and the sacroiliac joint decreased gradually from the top to the bottom. The widest distances for L4,5 were 2.1 cm (range, 1.74-2.40) and 2.7 cm (range, 2.34-3.02 cm), respectively. The smallest distances for L4, 5 were 1.2 cm (range, 0.82-1.48 cm) and 1.5 cm (range, 1.08-1.74 cm), respectively. On CT images, the angle between the sacroiliac joint and sagittal plane was about 30°.Conclusions: If we use two anterior plates to fix the sacroiliac joint, It is recommended to place one plate on the superior one third part of the joint, with exposing medially no more than 2.5 cm and the other in the middle one third part of the joint, with elevating periosteum medially no more than 1.5 cm. The screws in the sacrum are advised to incline medially about 30° directing to the true pelvis. [ABSTRACT FROM AUTHOR]

Background: Severe spasticity adversely affects patient functional status and caregiving. No previous study has compared efficacy between dorsal root entry zone lesioning (DREZL) and selective dorsal rhizotomy (SDR) for reduction of spasticity. This study aimed to investigate the efficacy of DREZL and SDR for attenuating spasticity, and to compare efficacy between these two methods. Methods: All patients who underwent DREZL, SDR, or both for treatment of intractable spasticity caused by cerebral pathology at Siriraj Hospital during 2009 to 2016 were recruited. Severity of spasticity was assessed using Modified Ashworth Scale (MAS) and Adductor Tone Rating Scale (ATRS). Ambulatory status was also evaluated. Results: Fifteen patients (13 males) with a mean age of 30.3 ± 17.5 years were included. Eight, six, and one patient underwent DREZL, SDR, and combined cervical DREZL and lumbosacral SDR, respectively. Eight of ten patients with preoperative bed-bound status had postoperative improvement in ambulatory status. Spasticity was significantly reduced in the DREZL group ( p < 0.001), the SDR group ( p < 0.001), and in overall analysis ( p < 0.001). SDR was effective in both pediatric and adult spasticity patients. A significantly greater reduction in spasticity as assessed by MAS score ( p < 0.001) and ATRS score ( p = 0.015) was found in the DREZL group. Transient lower limb weakness was found in a patient who underwent SDR. Conclusions: DREZL is more effective for reducing spasticity, but is more destructive than SDR. DREZL should be preferred for bed-ridden patients, and SDR for ambulatory patients. Both operations are helpful for improving ambulatory status. Gait improvement was observed only in patients who underwent SDR. Adult patients with spasticity of cerebral origin benefit from SDR. [ABSTRACT FROM AUTHOR]

Aim: To examine long-term outcomes of selective dorsal rhizotomy (SDR) 10 to 17 years after surgery.Method: Participants who underwent SDR had spastic diplegic cerebral palsy (CP), completed baseline gait analysis, and were 16 to 25 years old at follow-up. Non-SDR participants (i.e. controls) were matched on important clinical parameters at baseline but did not undergo SDR. All study participants completed six surveys assessing pain, quality of life, participation, function, and mobility. Treatment history for lower extremity surgery and antispasticity injections was tabulated. A subset of each study group returned for three-dimensional gait analysis, including kinematics, metabolic energy cost, and physical examination. Gait Deviation Index (GDI) was calculated to measure gait quality.Results: The study cohort had 24 participants with SDR and 11 without SDR. Of these, 13 patients with SDR (five males, eight females; median [IQR] age 17y 2mo [16y 8mo-17y 9mo]) and eight without SDR (three males, five females; median [IQR] age 19y 2mo [17y 3mo-21y 11mo]) completed baseline and follow-up gait analysis. Spasticity significantly decreased in those with SDR (p<0.05). Gait Deviation Index improved more in participants without SDR than those with SDR (Δnon-SDR =12.8 vs ΔSDR =9.1; p=0.01). Compared with the SDR group, participants without SDR underwent significantly more subsequent interventions (p<0.05).Interpretation: Patients in both the SDR and non-SDR groups showed improved gait quality more than 10 years after surgery. Participants without SDR had a larger improvement in gait pathology but underwent significantly more intervention. There were no differences between groups in survey measures. These results suggest differing treatment courses provide similar outcomes into early adulthood.What This Paper Adds: Selective dorsal rhizotomy (SDR) and non-SDR groups had significant improvement in gait pathology over time. The non-SDR group had significantly better gait compared with the SDR group at follow-up. The groups had similar levels of energy cost, pain, and quality of life. Non-SDR participants underwent significantly more orthopaedic surgery and antispasticity injections than SDR participants. Use of a clinically similar control group highlights that different treatment courses may result in similar outcomes into young adulthood. [ABSTRACT FROM AUTHOR]

Background: Total lumbar facetectomy may be advantageous for exposure or to completely free a constricted nerve root. Objective: We retrospectively reviewed a single surgeon series without fusion for short and long term outcomes regarding radicular pain relief, subsequent relevant surgeries, and any identifiable instability. Methods: All operations in which a single, total lumbar facetectomy was performed were reviewed. A total of 222 patients were identified with a minimal follow-up of 3 months; 187 (84.2%) were available for long term follow-up ≥1 year by continued accessible health care records, correspondence, or mailed questionnaire. Results: Short term success (3-month follow-up) for radicular pain relief in 222 patients found the following results: 176 patients (79.3%) had no pain or minimal pain, and 16 patients (7.2%) were improved, and thus resulting in 192 (86.5%) with no pain, or improved radicular pain. 30 patients (13.5%) were postoperative failures at 3 months. Long term follow-up ≥1 year was available for 187 patients (84.2%); (range 1–17 years; mean 7 years); found the following results: 23/30 (76.6%) short term surgical failures remained failures in long term follow-up with (7 patients) or without (16 patients) further surgery of any kind; 13/16 improved patients at long term follow-up remained improved (6), were pain free (6), or worse (1); 19/151 no or minimal pain patients at long term follow-up recurred or worsened by 1 year or longer, 12/19 pursued a second surgery with (9) or without (4) fusion and many improved. A total of 13 patients had a subsequent fusion operation (6.95%). Discussion: Most patients do well in the short term for radicular pain relief. Most patients continue to do well in long term follow-up. Surgically induced clinical instability is uncommon in this highly selected series. [ABSTRACT FROM AUTHOR]

Purpose: Recently, it has been reported that impairment by an 8th cervical nerve root lesion can cause drop finger, namely C8 drop finger. Here, we report a clinical case series of C8 drop finger to reveal the clinical outcome of surgical treatments to allow for a better choice of treatment.Methods: The present study included 17 consecutive patients who were diagnosed as having C8 drop finger, in which muscle strength of the extensor digitorum communis (EDC) showed a manual muscle testing (MMT) grade of 3 or less. We retrospectively investigated the clinical characteristics of C8 drop finger and recovery of muscle power was measured by subtraction of preoperative MMT of the EDC from the final follow-up values.Results: Nine cases showed recovery of muscle power of EDC, whereas the remaining eight cases did not show any recovery including two cases of deterioration. None of the conservatively treated patients showed any recovery. Surgically treated cases included two cases of deterioration. In the cases showing recovery, recovery began 9.9 months after surgery on average and recovery took 13.8 months after surgery on average. There was a significant difference in the recovery of MMT grade between the groups treated conservatively and surgically (p = 0.049). Preoperative MMT grade of EDC showed a moderate correlation with postoperative recovery (r 2 = 0.45, p = 0.003). In other words, the severity of preoperative muscular weakness correlated negatively with postoperative recovery.Conclusions: C8 drop finger is better treated by surgery than conservative therapy. [ABSTRACT FROM AUTHOR]

Purpose: Sacrectomy is a highly demanding surgery representing the main treatment for primary tumors arising in the sacrum and pelvis. Unfortunately, it is correlated with loss of important function depending on the resection level and nerve roots sacrificed. The current literature regarding residual function after sacral resection comes from several small case series. The goal of this review is to appraise residual motor function and gait, sensitivity, bladder, bowel, and sexual function after sacrectomies, with consideration to the specific roots sacrificed.Methods: An exhaustive literature search was conducted. All manuscripts published before May 2015 regarding residual function after sacrectomy were considered; if a clear correlation between root level and functioning was not present, the paper was excluded. The review identified 15 retrospective case series, totaling 244 patients; 42 patients underwent sacrectomies sparing L4/L4, L4/L5 and L5/L5; 45 sparing both L5 and one or both S1 roots; 8 sparing both S1 and one S2; 48 sparing both S2; 11 sparing both S2 and one S3, 54 sparing both S3, 9 sparing both S3 and one or both S4, and 27 underwent unilateral variable resection.Results: Patients who underwent a sacrectomy maintained functionally normal ambulation in 56.2 % of cases when both S2 roots were spared, 94.1 % when both S3 were spared, and in 100 % of more distal resections. Normal bladder and bowel function were not present when both S2 were cut. When one S2 root was spared, normal bladder function was present in 25 % of cases; when both S2 were spared, 39.9 %; when one S3 was spared, 72.7 %; and when both S3 were spared, 83.3 %. Abnormal bowel function was present in 12.5 % of cases when both S1 and one S2 were spared; in 50.0 % of cases when both S2 were spared; and in 70 % of cases when one S3 was spared; if both S3 were spared, bowel function was normal in 94 % of cases. When even one S4 root was spared, normal bladder and bowel function were present in 100 % of cases. Unilateral sacral nerve root resection preserved normal bladder function in 75 % of cases and normal bowel function in 82.6 % of cases. Motor function depended on S1 root involvement.Conclusion: Total sacrectomy is associated with compromising important motor, bladder, bowel, sensitivity, and sexual function. Residual motor function is dependent on sparing L5 and S1 nerve roots. Bladder and bowel function is consistently compromised in higher sacrectomies; nevertheless, the probability of maintaining sufficient function increases progressively with the roots spared, especially when S3 nerve roots are spared. Unilateral resection is usually associated with more normal function. To the best of our knowledge, this is the first comprehensive literature review to analyze published reports of residual sacral nerve root function after sacrectomy. [ABSTRACT FROM AUTHOR]

Background: The relationship of pain relief from a recently presented CT-guided indirect cervical nerve root injection with local anesthetics and steroids to surgical decompression as a treatment for single-level cervical radiculopathy is not clear. This retrospective study aimed to compare the immediate and 6-week post-injection effects to the short- and long-term outcomes after surgical decompression, specifically in regard to pain relief. Methods: Patients ( n = 39, age 47 ± 10 years) who had undergone CT-guided indirect injection with local anesthetics and steroids as an initial treatment for single cervical nerve root radiculopathy and who subsequently needed surgical decompression were included retrospectively. Pain levels (VAS scores) were monitored before, immediately after, and 6 weeks after injection ( n = 34), as well as 6 weeks ( n = 38) and a mean of 25 months (SD ± 12) after surgical decompression ( n = 36). Correlation analysis was performed to find potential associations of pain relief after injection and after surgery to investigate the predictive value of post-injection pain relief. Results: There was no correlation between immediate pain relief after injection (−32 ± 27 %) and 6 weeks later (−7 ± 19 %), ( r = −0.023, p = 0.900). There was an association by tendency between immediate pain relief after injection and post-surgical pain relief at 6 weeks (−82 ± 27 %), ( r = 0.28, p = 0.08). Pain relief at follow-up remained high at −70 ± 21 % and was correlated with the immediate pain amelioration effect of the injection ( r = 0.37, p = 0.032). Five out of seven patients who reported no pain relief from injection had a pain relief from surgery in excess of 50 %. Conclusions: The amount of immediate radiculopathic pain relief after indirect cervical nerve root injection is associated with the amount of pain relief achieved at long-term follow-up after surgical decompression of single-level cervical radiculopathy. Patients can still expect sufficient pain relief from surgery even if they did not respond to the cervical infiltration. [ABSTRACT FROM AUTHOR]

Background/Aims: Selective dorsal rhizotomy for spastic cerebral palsy is an effective and well-validated surgical approach. Multiple techniques have been described in the past including multiple laminectomies and a single-level laminectomy at the level of the conus. There is considerable technical challenge involved with a single-level laminectomy approach. Methods: We report here a modification of the single- level laminectomy that selectively analyzes each individual nerve root with electromyography to separate dorsal and ventral nerve roots through comparison of stimulus responses. Results: In 18 children with cerebral palsy who underwent this operation there was a mean improvement in the Modified Ashworth Scale of 2.0 with no reported incidence of muscle weakness, sensory loss, or neurogenic bladder. Conclusion: This approach allows for a modification of selective dorsal rhizotomy through a single-level laminectomy and tailors the selection of nerve root sectioning to the individual patient of interest while still maintaining its effectiveness. [ABSTRACT FROM AUTHOR]

Purpose: This research examines an approach for enhancing the efficiency of spinal surgery utilising the technological capabilities and design functionalities of wearable headsets, in this case Google Glass. The aim was to improve the efficiency of the selective dorsal rhizotomy neurosurgical procedure initially through the use of Glass via an innovative approach to information design for an intraoperative monitoring display.Methods: Utilising primary and secondary research methods the development of a new electromyography response display for a wearable headset was undertaken.Results: Testing proved that Glass was fit for purpose and that the new intraoperative monitor design provided an example platform for the innovative intraoperative monitoring display; however, alternative wearable headsets such as the Microsoft HoloLens could also be equally viable.Conclusion: The new display design combined with the appropriate wearable technology could greatly benefit the selective dorsal rhizotomy procedure. [ABSTRACT FROM AUTHOR]

Purpose. Extraforaminal decompression of the L5 nerve root remains a challenge due to anatomic constraints, severe level-degeneration, and variable anatomy. The purpose of this study is to introduce the use of navigation for transmuscular transtubular decompression at the L5/S1 level and report on radiological features and clinical outcome. Methods. Ten patients who underwent a navigation-assisted extraforaminal decompression of the L5 nerve root were retrospectively analyzed. Results. Six patients had an extraforaminal herniated disc and four had a foraminal stenosis. The distance between the L5 transverse process and the para-articular notch of the sacrum was 12.1 mm in patients with a herniated disc and 8.1 mm in those with a foraminal stenosis. One patient had an early recurrence and another developed dysesthesia that resolved after 3 months. There was a significant improvement from preoperative to postoperative NRS with the results being sustainable at follow-up. ODI was also significantly improved after surgery. According to the Macnab grading scale, excellent or good outcomes were obtained in 8 patients and fair ones in 2. Conclusions. The navigated transmuscular transtubular approach to the lumbosacral junction allows for optimal placement of the retractor and excellent orientation particularly for foraminal stenosis or in cases of complex anatomy. [ABSTRACT FROM AUTHOR]

Objective: To construct and validate a model to predict responsible nerve roots in lumbar degenerative disease with diagnostic doubt (DD).Methods: From January 2009-January 2013, 163 patients with DD were assigned to the construction (n = 106) or validation sample (n = 57) according to different admission times to hospital. Outcome was assessed according to the Japanese Orthopedic Association (JOA) recovery rate as excellent, good, fair, and poor. The first two results were considered as effective clinical outcome (ECO). Baseline patient and clinical characteristics were considered as secondary variables. A multivariate logistic regression model was used to construct a model with the ECO as a dependent variable and other factors as explanatory variables. The odds ratios (ORs) of each risk factor were adjusted and transformed into a scoring system. Area under the curve (AUC) was calculated and validated in both internal and external samples. Moreover, calibration plot and predictive ability of this scoring system were also tested for further validation.Results: Patients with DD with ECOs in both construction and validation models were around 76 % (76.4 and 75.5 % respectively).Risk Factors: more preoperative visual analog pain scale (VAS) score (OR = 1.56, p < 0.01), stenosis levels of L4/5 or L5/S1 (OR = 1.44, p = 0.04), stenosis locations with neuroforamen (OR = 1.95, p = 0.01), neurological deficit (OR = 1.62, p = 0.01), and more VAS improvement of selective nerve route block (SNRB) (OR = 3.42, p = 0.02).Validation: the internal area under the curve (AUC) was 0.85, and the external AUC was 0.72, with a good calibration plot of prediction accuracy. Besides, the predictive ability of ECOs was not different from the actual results (p = 0.532).Conclusions: We have constructed and validated a predictive model for confirming responsible nerve roots in patients with DD. The associated risk factors were preoperative VAS score, stenosis levels of L4/5 or L5/S1, stenosis locations with neuroforamen, neurological deficit, and VAS improvement of SNRB. A tool such as this is beneficial in the preoperative counseling of patients, shared surgical decision making, and ultimately improving safety in spine surgery. [ABSTRACT FROM AUTHOR]

Spinal nerve root enhancement in pediatric patients is generally nonspecific, and clinical and laboratory correlation is essential. Nerve root enhancement indicates lack of integrity of the blood-nerve barrier. In this review, we will present a range of pediatric conditions that can present with spinal nerve root enhancement including inflammatory, infectious, hereditary, and neoplastic causes. Familiarity with the various pathologic entities associated with spinal nerve root enhancement is important for a concise differential diagnosis in the appropriate clinical setting. This will avoid unnecessary additional investigations. [ABSTRACT FROM AUTHOR]

Purpose: Total en bloc spondylectomy (TES) is accompanied by preoperative embolization of segmental arteries, which is limited to three consecutive levels to avoid the risk of spinal cord ischemia. We retrospectively examined the efficacy and safety of repeated TES with embolization of more than three levels of segmental arteries.Methods: Seven patients underwent TES twice for spinal metastases at different levels. Every patient underwent embolization of the bilateral segmental arteries before each surgery. We assessed the total number of segmental arteries embolized, the existence of Adamkiewicz arteries during the embolization procedure, intraoperative blood loss, and the motor function of the lower limbs, using the American Spinal Injury Association (ASIA) motor score.Results: No patient experienced any motor deficit after embolization. During the embolization procedure, an Adamkiewicz artery was depicted in five patients, which precluded embolization at that level. The median number of segmental arteries embolized in total was 9 (9-11). Intraoperative blood loss (median, IQR) was 480 (420-630) ml during the first surgery and 520 (280-600) ml during the second surgery. The ASIA motor scores (median, IQR) were as follows; 100 (98-100) (first admission), 100 (100-100) (first discharge), 100 (98-100) (second admission), and 97 (94-100) (second discharge). No patients had developed statistically significant neurological deterioration, and there had been no local recurrence after a median follow-up of 17.8 months (range 1-51 months).Conclusion: Repeated TES procedures can be performed safely even if more than three levels of segmental arteries are embolized. [ABSTRACT FROM AUTHOR]

Background context The posterior cervical foraminotomy (PCF) may be performed using an open or minimally-invasive (MIS) approach using a tubular retractor. Although there are theoretical advantages such as less blood loss and shorter hospitalizations, there is no consensus in the literature regarding the best approach for treatment. Purpose To assess clinical outcomes of PCF treated with either an open or an MIS approach using a tubular retractor. Study design Systematic literature review and meta-analysis of English language studies for the treatment of cervical radiculopathy treated with foraminotomy. Patient sample Pooled patient results from Level I studies and Level IV retrospective studies. Outcome measures Meta-analysis for clinical success as determined by Odom and Prolo criteria, and visual analog scale scores for arm and neck pain. Methods A literature search of three databases was performed to identify investigations performed in the treatment of PCF with an open or MIS approach. The pooled results were performed by calculating the effect size based on the logit event rate. Studies were weighted by the inverse of the variance, which included both within and between-study errors. Confidence intervals (CIs) were reported at 95%. Heterogeneity was assessed using the Q statistic and I-squared, where I-squared is the estimate of the percentage of error due to between-study variation. Results The initial literature search resulted in 195 articles, of which, 20 were determined as relevant on abstract review. An open foraminotomy approach was performed in six; similarly, an MIS approach was performed in three studies. The pooled clinical success rate was 92.7% (CI: 88.9, 95.3) for open foraminotomy and 94.9% (CI: 90.5, 97.4) for MIS foraminotomy, which was not statistically significant (p=.418). The open group demonstrated relative homogeneity with Q value of 7.6 and I 2 value of 34.3%; similarly, the MIS group demonstrated moderate study heterogeneity with Q value of 4.44 and I 2 value of 54.94%. Conclusions Patients with symptomatic cervical radiculopathy from foraminal stenosis can be effectively managed with either a traditional open or an MIS foraminotomy. There is no significant difference in the pooled outcomes between the two groups. [ABSTRACT FROM AUTHOR]

Background/Study Aims Percutaneous radiofrequency trigeminal rhizotomy (RTR) is a standardized treatment for trigeminal neuralgia, yet it has been associated with serious complications related to the cannulation of the foramen ovale. Some of these complications, such as carotid injury, are potentially lethal. Neuronavigation was recently proposed as a method to increase the procedure's safety. All of the techniques described so far rely on pre- or intraoperative computed tomography scanning. Here we present a simple method based on magnetic resonance imaging (MRI) (radiation free) used to target the foramen ovale under navigation guidance. Patients/Material and Methods We retrospectively analyzed nine patients who had undergone navigated percutaneous RTR based solely on preoperative MRI and compared them with 35 patients who underwent conventional RTR guided by fluoroscopy. We analyzed immediate and late outcome and categorized the results into pain free, > 70% pain reduction, and persistent pain. We also compared groups in terms of the duration of the procedure and the complication rates. Here we describe the navigation method in detail and review the anatomical landmarks for target definition. Results The duration of the surgical procedure was similar in both groups (32.1 in the standard technique versus 34.5 minutes with navigation; p = 0.5157). There was no significant difference between groups regarding pain reduction at the immediate (p = 1.0) or late follow-up (p = 0.6284) time points. Furthermore, no serious complications were observed in the navigated group. Conclusions We present a simple radiation-free method for neuronavigation-assisted percutaneous RTR. This method proved to be safe and effective, and it is especially recommended for young, inexperienced neurosurgeons. [ABSTRACT FROM AUTHOR]

We recently proposed a new surgical approach to treat ventral root avulsion, resulting in motoneuron protection. The present work combined such a surgical approach with bone marrow mononuclear cells (MC) therapy. Therefore, MC were added to the site of reimplantation. Female Lewis rats (seven weeks old) were subjected to unilateral ventral root avulsion (VRA) at L4, L5 and L6 levels and divided into the following groups (n = 5 for each group): Avulsion, sealant reimplanted roots and sealant reimplanted roots plus MC. After four weeks and 12 weeks post-surgery, the lumbar intumescences were processed by transmission electron microscopy, to analyze synaptic inputs to the repaired a motoneurons. Also, the ipsi and contralateral sciatic nerves were processed for axon counting and morphometry. The ultrastructural results indicated a significant preservation of inhibitory pre-synaptic boutons in the groups repaired with sealant alone and associated with MC therapy. Moreover, the average number of axons was higher in treated groups when compared to avulsion only. Complementary to the fiber counting, the morphometric analysis of axonal diameter and "g" ratio demonstrated that root reimplantation improved the motor component recovery. In conclusion, the data herein demonstrate that root reimplantation at the lesion site may be considered a therapeutic approach, following proximal lesions in the interface of central nervous system (CNS) and peripheral nervous system (PNS), and that MC therapy does not further improve the regenerative recovery, up to 12 weeks post lesion. [ABSTRACT FROM AUTHOR]

Background: In total en bloc spondylectomy (TES) of upper thoracic spine including the second thoracic (T2) vertebra, T2 nerve roots are usually transected. In this study, we examined the association between transection of the T2 nerve roots and upper-extremity motor function in patients with upper thoracic TES. Methods: We assessed 16 patients who underwent upper thoracic TES with bilateral transection of the T2 nerve roots. Patients were divided into three groups: 3 patients without any processing of T1 and upper nerve roots (T2 group), 7 with extensive dissection of T1 nerve roots (T1–2 group), and 6 with extensive dissection of T1 and upper nerve roots (C–T2 group). Postoperative upper-extremity motor function was compared between the groups. Results: Postoperative deterioration of upper-extremity motor function was observed in 9 of the 16 patients (56.3%). Three of the 7 patients in the T1–2 group and all 6 patients in the C–T2 group showed deterioration of upper-extremity motor function, but there was no deterioration in the T2 group. In the T1–2 group, 3 patients showed mild deterioration that did not affect their activities of daily living and they achieved complete recovery at the latest follow-up examination. In contrast, severe dysfunction occurred frequently in the C–T2 group, without recovery at the latest follow-up. Conclusions: The transection of the T2 nerve roots alone did not result in upper-extremity motor dysfunction; rather, the dysfunction is caused by the extensive dissection of the T1 and upper nerve roots. Therefore, transection of the T2 nerve roots in upper thoracic TES seems to be an acceptable procedure with satisfactory outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Background context: Decompressive procedures such as laminectomy, facetectomy, and costotransversectomy are routinely performed for various pathologies in the thoracic spine. The thoracic spine is unique, in part, because of the sternocostovertebral articulations that provide additional strength to the region relative to the cervical and lumbar spines. During decompressive surgeries, stability is compromised at a presently unknown point. Purpose: To evaluate thoracic spinal stability after common surgical decompressive procedures in thoracic spines with intact sternocostovertebral articulations. Study design: Biomechanical cadaveric study. Methods: Fresh-frozen human cadaveric spine specimens with intact rib cages, C7–L1 (n=9), were used. An industrial robot tested all spines in axial rotation (AR), lateral bending (LB), and flexion-extension (FE) by applying pure moments (±5 Nm). The specimens were first tested in their intact state and then tested after each of the following sequential surgical decompressive procedures at T4–T5 consisting of laminectomy; unilateral facetectomy; unilateral costotransversectomy, and subsequently instrumented fusion from T3–T7. Results: We found that in all three planes of motion, the sequential decompressive procedures caused no statistically significant change in motion between T3–T7 or T1–T12 when compared with intact. In comparing between intact and instrumented specimens, our study found that instrumentation reduced global range of motion (ROM) between T1–T12 by 16.3% (p=.001), 12% (p=.002), and 18.4% (p=.0004) for AR, FE, and LB, respectively. Age showed a negative correlation with motion in FE (r=−0.78, p=.01) and AR (r=−0.7, p=.04). Conclusions: Thoracic spine stability was not significantly affected by sequential decompressive procedures in thoracic segments at the level of the true ribs in all three planes of motion in intact thoracic specimens. Age appeared to negatively correlate with ROM of the specimen. Our study suggests that thoracic spinal stability is maintained immediately after unilateral decompression at the level of the true ribs. These preliminary observations, however, do not depict the long-term sequelae of such procedures and warrant further investigation. [Copyright &y& Elsevier]

Management of brachial plexus injury is a demanding field of hand and upper extremity surgery. With currently available microsurgical techniques, functional gains are rewarding in upper plexus injuries. However, treatment options in the management of flail and anaesthetic limb are still evolving. Last three decades have witnessed significant developments in the management of these injuries, which include a better understanding of the anatomy, advances in the diagnostic modalities, incorporation of intra-operative nerve stimulation techniques, more liberal use of nerve grafts in bridging nerve gaps, and the addition of new nerve transfers, which selectively neurotise the target muscles close to the motor end plates. Newer research works on the use of nerve allografts and immune modulators (FK 506) are under evaluation in further improving the results in nerve reconstruction. Direct reimplantation of avulsed spinal nerve roots into the spinal cord is another area of research in brachial plexus reconstruction. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to report the survival analysis of partial lateral facetectomy and Insall's procedure in patients with isolated patellofemoral osteoarthritis, and to assess the risk and protective factors for failure of this procedure. Methods: From 1992 to 2004, all subjects with isolated patellofemoral osteoarthritis who met the inclusion criteria and underwent this procedure were enrolled. Risk and protective factors for failure (failure considered as the need for total knee arthroplasty) were assessed by comparing obtained baseline data between failed and non-failed cases. Eighty-seven cases (mean (SD) age 61.8 (7.7) years, mean (SD) follow-up 9.6 (3.2) years) were included. Results: Twenty-three failed cases were found. Mean (SD) survival time was 13.6 (0.5) years. At 13 years (last failure case), the cumulative survival was 59.3 %. Baseline medial tibiofemoral pain, genu flexum, and worst grade of tibiofemoral osteoarthritis were significant risk factors for failure ( p < 0.0001, p = 0.02, p < 0.0001, respectively). In contrast, higher anatomical ( p = 0.02) and total ( p = 0.03) knee society score (KSS) scores, absence of knee effusion ( p = 0.03), higher value of the Caton-Deschamps index ( p = 0.03), and lateral position of the patella ( p = 0.01) were all protective factors against failure. Conclusion: The treatment for isolated patellofemoral osteoarthritis through partial lateral facetectomy and Insall's procedure demonstrated good long-term survival. The presence of preoperative medial tibiofemoral pain, genu flexum, and incipient tibiofemoral osteoarthritis increased the risk of failure of this procedure. In contrast, higher anatomical and total KSS scores, absence of knee effusion, higher value of the Caton-Deschamps index, and lateral position of the patella were found to protect against failure. Level of evidence: Prospective case series, Level IV. [ABSTRACT FROM AUTHOR]

Background: It is widely believed that the main function of denticulate ligaments (DLs) is to stabilize the spinal cord within the vertebral canal. The aim of this study was to assess the anatomical and histological structure of the DLs and to document any regional differences. Methods: Five formalin-fixed adult cadavers were used. The DLs were exposed via the posterior approach, and detailed anatomy and histology of these structures were documented. Results: The main findings were: (1) each DL is composed of a single narrow fibrous strip that extends from the craniovertebral junction to T12, and each also features 18-20 triangular extensions that attach to the dura at their apices; (2) the triangular extensions are smaller and more numerous at the cervical levels, and are larger and less numerous at the thoracic levels; (3) the apices of the extensions attach to the dura via fibrous bands at cervical levels (each band 3-5 mm long) and lower thoracic levels (21-26 mm long), whereas they attach directly to the dura at upper thoracic levels; (4) the narrow fibrous strip of the DL features longitudinally oriented collagen fibers, whereas the triangular extensions are composed of transverse and obliquely oriented collagen fibers. The collagen fibers are thicker and more abundant at the cervical than at the thoracic levels. Conclusion: DL histology and anatomy are strongly correlated with the function of this structure at different spinal levels. It is important to have accurate knowledge about DLs as these structures are relevant for clinical procedures that involve the spinal cord or craniovertebral junction. [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to evaluate the effectiveness of percutaneous controlled radiofrequency trigeminal rhizotomy (RF-TR) in patients with bilateral trigeminal neuralgia (BTN). Patients were analyzed after RF-TR in terms of outcome, safety and complications. Methods: Eighty-nine BTN patients underwent 186 RF-TR procedures. Eighty-seven patients had idiopathic trigeminal neuralgia (ITN) and two patients had multiple sclerosis (2.2%). Fifty-six (62.9%) were women and 33 (37.1%) were men. Ages ranged from 29 to 85 years. Anesthesia was administered at a determined optimal level, allowing patient cooperation for controlled and selective lesioning. Results: The mean follow-up period was 101.71 ± 77.7 months. Familial occurrence was seen in two (2.2%) patients. Synchronized pain was observed in 25 (28.2%) patients. Pain occurrence on the contralateral side was observed with an average duration of 124.7 ± 87.13 months. Fifty-four of the 89 patients underwent 146 RF-TR procedures for both sides and 35 underwent 40 RF-TR procedures for one side. Complete pain relief or partial satisfactory pain relief was achieved on the medically treated side in 35 patients. During follow-up, 36 patients required the second procedure and 7 required the third procedure. Acute pain relief was reported in 86 (96.6%) patients. Early (<6 months) pain recurrence was observed in 11 (12.3%) and late (>6 months) recurrence in 25 (28.0%) patients. Complications included diminished corneal reflex in four (2.1%) patients, keratitis in two (1.1%), masseter dysfunction in four (2.1%), dysesthesia in two (1.1%), and anesthesia dolorosa in one (0.5%). Conclusions: RF-TR is an effective, selective, well-controlled, and effortlessly repeatable procedure for treating BTN, especially in the elderly, in terms of low morbidity and mortality rates and high rate of satisfactory pain relief. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to explore changes in motor function up to 10 years after selective dorsal rhizotomy (SDR). Method The participants comprised 29 children (20 males, nine females) with bilateral spastic diplegia who were consecutively operated on at a median age of 4 years and 3 months and followed until a median age of 15 years. SDR was combined with physiotherapy and regular follow-up visits. The distribution of preoperative Gross Motor Function Classification System (GMFCS) levels was as follows: I, n=1; II, n=7; III, n=8; IV, n=12; and V, n=1. Muscle tone in hip flexors, hip adductors, knee flexors, and plantar flexors was assessed with the modified Ashworth scale, passive range of motion in hip abduction, popliteal angle, maximum knee extension, dorsiflexion of the foot was measured with a goniometer, and gross motor function was assessed using the Gross Motor Function Measure (GMFM-66). The results were compared with preoperative values, taking into account age at the time of SDR. Results After 10 years, muscle tone in hip flexors, hip adductors, knee flexors and plantar flexors was normalized in 19, 24, 13 and 23 participants respectively; mean change in passive range of motion ranged from −2.0° to 8.6°, and the mean increase in GMFM-66 was 10.6. Changes in GMFM-66 were associated with preoperative GMFCS level and GMFM-66 scores. Interpretation Children who underwent SDR and physiotherapy and were regularly followed up by an experienced team showed improved gross motor function for up to 10 years postoperatively. [ABSTRACT FROM AUTHOR]

Purpose: The use of contralateral C7 is seldom indicated in infants with obstetrical brachial plexus palsy (OBPP). The purpose of this study was to evaluate the value of contralateral C7 transfer in infants with upper OBPP in order to define the application and outcome of this transfer in these infants more optimally.Methods: Over a 5-year period, 15 infants with upper brachial plexus injuries underwent transfer of the contralateral C7 as part of the primary surgical reconstruction. The common trunk of the contralateral C7 root was transferred to the upper trunk or lateral cord on the affected side with nerve graft. The efficacy of the surgery and effects of patient age at the time of nerve transfer were analyzed.Results: Patients were followed up for a mean duration of 46.8 months. Noteworthy function (≥M2+) was gained in 11 of 15 patients, and sensory function (≥S3, MRC grading system) was gained in all patients. Age was not the factor related to the outcome of this surgery.Conclusions: Contralateral C7 transfer is an effective procedure for the restoration of upper limb function in infants with OBPP and root avulsions. [ABSTRACT FROM AUTHOR]

Objectives. We aim to determine the effects of Botulinum toxin type A (BTX-A) on neuropathic pain behavior and the expression of P2X3 receptor in dorsal root ganglion (DRG) in rats with neuropathic pain induced by L5 ventral root transection (L5 VRT). Methods. Neuropathic pain was induced by L5 VRT in male Sprague-Dawley rats. Either saline or BTX-A was administered to the plantar surface. Behavioral tests were conducted preoperatively and at predefined postoperative days. The expression of P2X3 receptors in DRG neurons was detected by immunoreactivity at postoperative days 3, 7, 14, and 21. Results. The number of positive P2X3 neurons in the ipsilateral L5 DRG increased significantly after L5 VRT ( P < 0.001). This increase persisted for at least 3 weeks after the operation. No significant changes in P2X3 expression were detected in the contralateral L5, or in the L4 DRGs bilaterally. Subcutaneous administration of BTX-A, performed on the left hindpaw at days 4, 8, or 16 post VRT surgery, significantly reduced mechanical allodynia bilaterally and inhibited P2X3 over-expression induced by L5 VRT. Conclusions. L5 VRT led to over-expression of P2X3 receptors in the L5 DRG and bilateral mechanical allodynia in rats. Subcutaneous injection of BTX-A significantly reversed the neuropathic pain behavior and the over-expression of P2X3 receptor in nociceptive neurons. These data not only show over-expression of purinergic receptors in the VRT model of neuropathic pain but also reveal a novel mechanism of botulinum toxin action on nociceptive neurons. [ABSTRACT FROM AUTHOR]

Background: This is a unique report of 40 patients litigating in relation to the management of a cauda equina syndrome (CES), with prospective data collection. Methods: Patients were seen and examined; medical records and radiological imaging were reviewed. The following data were collected prospectively: age; sex; the level of cauda equina (CE) compression; the pathology causing the compression; the clinical picture at first presentation; the causes of any iatrogenic injury; possible breaches of duty of care and the responsible discipline; recovery of bladder control; return to work. Findings: There were possible breaches of duty of care for 39 patients initially, and for 69 patients overall. Twenty-eight patients presented with compressive degenerative pathologies (mainly central disc prolapses); all 28 had deteriorated to the point of bladder paralysis (complete CES (CESR)) at the time of treatment. Twenty-six (93%%) had voluntary bladder control at presentation. Long-term bladder paralysis was probably avoidable in over 90%% of patients. Eleven patients had iatrogenic injuries: all had long-term bladder paralysis. Thirty-four patients had bladder paralysis (CESR) at the point of decompressive surgery. Recovery of bladder function occurred in only seven patients (21%%), i.e. long-term bladder outcomes were poor. Only 22%% of patients returned to work. Conclusion: In this highly selected group of patients whose CES was not managed in an appropriate/standard fashion, 93%% of patients had long-term bladder, bowel and sexual dysfunction that was probably avoidable. Mismanagement of patients with iatrogenic injuries was associated with a universally poor outcome. [ABSTRACT FROM AUTHOR]

The article discusses a study that evaluated the long-term effects of selective dorsal rhizotomy (SDR) in pediatric patients with cerebral palsy (CP). The subjects were prospectively assessed at different time periods after SDR. It was found that baseline muscle tone at the knee, hop, and ankle level showed a high degree of spasticity that normalized after SDR. The spasticity-reducing effect of SDR is seen to suggest that contracture development in CP is not mediated only by spasticity.

The article discusses a study that compares function and gait in a group of certain older children who received selective dorsal rhizotomy (SDR) with age- and function-matched children who received either no surgery or orthopedic surgery. Ambulatory children with diplegic cerebral palsy and categorized in levels I or II of the Gross Motor Function Classification System (GMFCS). It was found that the group that received orthopedic surgery showed improved gait compared with the group that did not undergo surgery.

Afferent inputs are known to modulate the activity of locomotor central pattern generators, but their role in the generation of locomotor patterns remains uncertain. This study sought to investigate the importance of afferent input for producing bilateral, coordinated hindlimb stepping in adult cats. Following complete spinal transection, animals were trained to step on the moving belt of a treadmill until proficient, weight-bearing stepping of the hindlimbs was established. Selective dorsal rhizotomies of roots reaching various segments of the lumbosacral enlargement were then conducted, and hindlimb stepping capacity was reassessed. Depending on the deafferented lumbosacral segments, stepping was either abolished or unaffected. Deafferentation of mid-lumbar (L3/L4) or lower-lumbar (L5-S1) segments abolished locomotion. Locomotor capacity in these animals could not be restored with the administration of serotonergic or adrenergic agonists. Deafferentation of L3, L6, or S1 had mild effects on locomotion. This suggested that critical afferent inputs pertaining to hip position (mid-lumbar) and limb loading (lower-lumbar) play an important role in the generation of locomotor patterns after spinal cord injury. [ABSTRACT FROM AUTHOR]

Temperature sense and pain appreciation in the dermatomes of the cauda equina roots were estimated in patients with lumbar intervertebral disk hernias before surgery, as well as immediately and long after surgery for disk herniation. Before surgery, the temperature sense and pain appreciation were impaired not only in the dermatome of the compressed root, but also in the dermatomes located proximal and distal to it. The temperature sense was impaired more severely. The recovery of the temperature sense and pain appreciation in the dermatomes of the cauda equina roots after surgery is limited, especially in the region innervated by the compressed root. Positive changes in temperature sense and pain appreciation in different zones examined soon after surgery were observed, on average, in 55% of cases, whereas delayed positive changes were detected only in 36% of the patients. Pain appreciation (in tests with heat pain) both immediately and long after surgery was improved to a higher degree. [ABSTRACT FROM AUTHOR]

Abstract: The relationship between pain severity and the extent of injury to a peripheral nerve remains elusive. In this study, we compared the pain behavior resulting from partial (1/3–1/2 thickness) and full L5 spinal nerve ligation (SNL) in rats. The decrease in paw withdrawal threshold (PWT) to mechanical stimuli in the hindpaw ipsilateral to the injury was comparable in the two groups on days 3–21 post-injury. However, the decreased PWT recovered earlier in the partial SNL group than in the full SNL group. These observations suggest that the duration of neuropathic pain behavior, but not the early development of mechanical allodynia, is dependent on the extent of nerve injury. On days 6 and 15 post-injury, when the mechanical allodynia was similar in the two groups, systemic morphine induced a greater reduction of mechanical allodynia in the partial SNL group than in the full SNL group. Furthermore, in partial SNL rats, at post-injury time points when they had largely recovered from the neuropathic pain state, systemic administration of naloxone hydrochloride (day 53) or naloxone methiodide (a non-selective peripherally acting opioid receptor antagonist; day 64) or intra-plantar injection of naloxone methiodide rekindled mechanical pain hypersensitivity in the ipsilateral hindpaw, suggesting a prolonged activation of endogenous opioidergic pain-inhibition. Therefore, partial SNL in rats may represent an efficient model for studying the mechanisms of neuropathic pain, testing effects of analgesic/antihyperalgesic drugs, and understanding endogenous pain-inhibitory mechanisms that lead to reversal of the pain behavior with time. [Copyright &y& Elsevier]

The foramen of Vesalius (FV) is located in the greater wing of the sphenoid bone between the foramen ovale (FO) and the foramen rotundum in an intracranial view. The FO allows the passage of the mandibular branch of trigeminal nerve, which is the target of the trigeminal radiofrequency rhizotomy. We analyzed its location, morphology, morphometry and interrelation among other foramina. 400 macerated adult human skulls were examined. A digital microscope (Dino-Lite plus®) was used to capture images from the FV. A digital caliper was used to perform the measurements of the distance between the FV and other foramina (FO, foramen spinosum and the carotid canal) in an extracranial view of the skull base. In the 400 analyzed skulls, the FV was identified in 135 skulls (33.75%) and absent on both sides in 265 skulls (66.25%). The FV was observed present bilaterally in 15.5% of the skulls. The incidence of unilateral foramen was 18.25% of the skulls of which 7.75% on right side and 10.5% on left side. The diameter of the FV was measured and we found an average value of 0.65 mm, on right side 0.63 mm and on the left side 0.67 mm. We verified that positive correlations were statistically significant among the three analyzed distances. This study intends to offer specific anatomical data with morphological patterns (macroscopic and mesoscopic) to increase the understanding of the FV features as frequency, incidence and important distances among adjacent foramina. [ABSTRACT FROM AUTHOR]