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In patients with severe upper extremity weakness that may result from peripheral nerve injuries, stroke, and spinal cord injuries, standard therapy in the earliest stages of recovery consists primarily of passive rather than active exercises. Adherence to prescribed therapy may be poor, which may contribute to suboptimal functional outcomes. The authors have developed and integrated a custom surface electromyography device with a video game to create an interactive, biofeedback-based therapeutic gaming platform. Sensitivity of the authors' custom surface electromyography device was evaluated with simultaneous needle electromyography recordings. Testing of this therapeutic gaming platform was conducted with a single 30-minute gameplay session in 19 patients with a history of peripheral nerve injury, stroke, spinal cord injury, and direct upper extremity trauma, including 11 patients who had undergone nerve and/or tendon transfers. The device was highly sensitive in detecting low levels of voluntary muscle activation and was used with 10 distinct muscles of the arm, forearm, and hand. Nerve and tendon transfer patients successfully activated the donor nerve/muscle and elicited the desired movement to engage in gameplay. On surveys of acceptability and usability, patients felt the system was enjoyable, motivating, fun, and easy to use, and their hand therapists expressed similar enthusiasm. Surface electromyography-based therapeutic gaming is a promising approach to rehabilitation that warrants further development and investigation to examine its potential efficacy, not only for building muscle strength and endurance but also for facilitating motor relearning after nerve and tendon transfer surgical procedures.Therapeutic, IV.

Symptomatic neuromas and chronic neuropathic pain are significant problems affecting patients' quality of life and independence that are challenging to treat. These symptoms are due to structural and functional changes that occur peripherally within neuromas, as well as alterations that occur centrally within the brain and spinal cord. A multimodal approach is most effective, with goals to minimize opioid use, to capitalize on the synergistic effects of nonopioid medications and to explore potential benefits of novel adjunctive treatments.

Purpose Biomaterials used to restore digital nerve continuity after injury associated with a defect may influence ultimate outcomes. An evaluation of matched cohorts undergoing digital nerve gap reconstruction was conducted to compare processed nerve allograft (PNA) and conduits. Based on scientific evidence and historical controls, we hypothesized that outcomes of PNA would be better than for conduit reconstruction. Methods We identified matched cohorts based on patient characteristics, medical history, mechanism of injury, and time to repair for digital nerve injuries with gaps up to 25 mm. Data were stratified into 2 gap length groups: short gaps of 14 mm or less and long gaps of 15 to 25 mm. Meaningful sensory recovery was defined as a Medical Research Council scale of S3 or greater. Comparisons of meaningful recovery were made by repair method between and across the gap length groups. Results Eight institutions contributed matched data sets for 110 subjects with 162 injuries. Outcomes data were available in 113 PNA and 49 conduit repairs. Meaningful recovery was reported in 61% of the conduit group, compared with 88% in the PNA group. In the group with a 14-mm or less gap, conduit and PNA outcomes were 67% and 92% meaningful recovery, respectively. In the 15- to 25-mm gap length group, conduit and PNA outcomes were 45% and 85% meaningful recovery, respectively. There were no reported adverse events in either treatment group. Conclusions Outcomes of digital nerve reconstruction in this study using PNA were consistent and significantly better than those of conduits across all groups. As gap lengths increased, the proportion of patients in the conduit group with meaningful recovery decreased. This study supports the use of PNA for nerve gap reconstruction in digital nerve reconstructions up to 25 mm. Type of study/level of evidence Therapeutic III.

Multiple prior studies have assessed the results of open approaches for concurrent carpal tunnel release with distal radius fracture fixation; however, less is known regarding the feasibility of endoscopic techniques, especially in the setting of high-energy trauma. In this study, we assessed the feasibility and results of concurrent endoscopic carpal tunnel release and distal radius fracture fixation using the flexor carpi radialis approach after high- and low-energy trauma.We performed a retrospective, single-surgeon study of 17 consecutive adult patients (aged18 years) who underwent open reduction internal fixation of an acute distal radius fracture with concurrent endoscopic carpal tunnel release at a level 1 trauma center between April 2017 and October 2020. Recovery from median nerve dysfunction was assessed from patient charts at routinely scheduled postoperative follow-up visits (at 2 weeks, 4 weeks, 6 weeks, and 12 weeks).The transverse carpal ligament could be visualized and released in all patients. All patients had a return of light touch sensibility with or without intermittent paresthesia by 12 weeks after surgery (the median time from surgery to recovery was 19 days [range, 12-82 days]). There were no patient reports or clinical examination evidence of palmar cutaneous branch, recurrent motor branch, or the third common digital nerve injury. Time to recovery was significantly different in the setting of high- versus low-energy trauma (26 days vs 18 days, respectively;In this study, we demonstrated that concurrent endoscopic carpal tunnel release using the flexor carpi radialis approach for distal radius fracture fixation in the settings of high- and low-energy trauma is safe from major complications and effective at releasing the transverse carpal ligament.Therapeutic IV.

Background: Desmoid tumor and leiomyoma are abdominal wall tumors with similar clinical, radiographic, and histological features. However, differentiation between these two diseases is important because each may be linked to different systemic diseases, and their managements are entirely different. We proposed that misdiagnosis is possible in some cases. Patients and Methods: Between 1983 and 2010, patients with a history of uterine surgeries and diagnosed with either abdominal wall desmoid tumors or leiomyomas were studied. All the images reviewed by an independent radiologist and surgical specimen were reexamined by immunohistochemistry (IHC) techniques as a standard method to confirm the diagnoses. Results: Fifteen female patients (desmoid tumors, n = 10; leiomyomas, n = 5) were included. The diagnosis of IHC revealed that two cases initially thought to be leiomyomas were desmoid tumors, whereas the remaining 13 cases maintained their initial diagnoses. The accuracy of hematoxylin and eosin staining was 86.7%. All tumors excised without complications, except for one desmoid tumor that recurred and underwent another excision. Conclusion: Preoperative magnetic resonance imaging (MRI) can be considered to differentiate the two diseases, as well as the elimination of other associated systemic diseases should be performed routinely. If MRI is inaccessible or unavailable, preoperative fine-needle biopsy is recommended. Optional IHC staining is required if the primary histological assessment is equivocal or inconclusive.

Traumatic thumb amputation can have devastating effects on residual hand function. When replantation is not possible, thumb reconstruction is often performed in a delayed manner and may require multiple stages. Furthermore, reconstruction techniques often require microsurgical skills and equipment, which are not readily available at all institutions. This case series illustrates our technique for immediate osteoplastic thumb reconstruction following traumatic amputation.This is a case series involving all patients who sustained unreplantable thumb amputations and underwent immediate osteoplastic thumb reconstruction with bone autograft and pedicled groin flap by the senior author from September 2016 through August 2018.Five patients underwent immediate osteoplastic thumb reconstruction during the study period. Total operative time for the initial osteoplastic reconstruction averaged 158 minutes (range 96-290 minutes). In addition to flap division surgery, patients underwent an average of 1.2 revision procedures (range 0-2), primarily for debulking and hardware removal. Patients achieved an average gain in length of 3.3 cm compared with the maximum anticipated length with revision amputation at the time of injury, and had stable clinical outcomes for a minimum of 12 months.Osteoplastic thumb reconstruction is a useful technique for thumb reconstruction for select patients following traumatic thumb amputation. Advantages of this approach include shorter overall operative times and hospital length of stay, minimal donor site morbidity, and a straightforward, reproducible technique.

Summary. Nerve transection injuries can result in painful neuromas that adversely affect patient recovery. This is especially significant following amputation surgeries in the setting of prosthetic wear and function. Targeted Muscle Reinnervation and Regenerative Peripheral Nerve Interface (RPNI) are 2 modern surgical techniques that provide neuromuscular targets for these transected nerve endings to reinnervate. These strategies have been previously shown to reduce phantom limb pain, residual limb pain, and neuroma-related pain.1,2,7,11 Two recent articles described technical adaptations of combining targeted muscle reinnervation and RPNI to create a hybrid procedure.3,12 In this article, we propose a different modification of targeted muscle reinnervation and RPNI, where the transected nerve stump is coapted to a recipient unit consisting of an intact distal nerve branch with its associated muscle graft. We called this recipient unit a targeted peripheral nerve interface because it contains a distal nerve branch for nerve coaptation and can guide axonal regeneration from the donor nerve to its target muscle graft. We theorize that targeted peripheral nerve interface may lead to more even distribution of regenerating axons with potentially less pain and stronger signals for prosthetic control when compared with standard RPNI.

Summary:. Desmoid tumors are a rare, locally invasive, non-metastasizing tumor of mesenchymal origin. Most of such tumors occur sporadically, but some arise as part of germline adenomatous polyposis coli mutations. They tend to aggregate in the abdomen, thorax, extremities, and the head and neck region. They are challenging to treat, with a high rate of recurrence even if achieving negative margins. We present the case of an 18-year-old woman with a desmoid tumor involving her brachial plexus. A non-oncological resection was performed, with a focus on functional preservation. Residual disease is being treated with β-catenin inhibitor and monitored with serial MRI.

Simply stated, pain is the brain’s response to potentially harmful stimuli sensed by specialized receptors along the peripheral nervous system. Stretch, compression, and certainly severance of a peripheral nerve will cause pain and dysfunction.

Background Surgical options for the unreconstructable elbow are limited to arthrodesis, total arthroplasty, or osteoarticular allograft reconstruction. Each of these options is limited by severe functional impairment and/or high complication rates. Vascularized allotransplantation of the elbow joint has the potential to mitigate these complications. In this study, we describe our technique for harvesting the elbow for vascularized joint transplantation and demonstrate the flap's vascularity using contrast angiography. Methods Anatomical studies were used to design and harvest a vascularized elbow joint flap pedicled on the brachial vessels in 10 cadaveric arms. Diaphyseal blood supply is provided by 3 nutrient arteries, and periarticular supply arises from the various collateral arteries of the arm and recurrent arteries of the forearm. The brachialis and supinator, and their respective nerves, were included as functional muscles because of their intimate association with critical vasculature. Tendinous insertions of the biceps and triceps, as well as the flexor/pronator and extensor origins, were preserved for repair in the transplant recipient. Both lateral arm and radial forearm flaps were preserved to aid in soft tissue inset as well as vascular/immunologic monitoring. Contrast angiography of each dissected specimen was performed to assess the location of the nutrient vessels and assess flap vascularity, as indicated by filling of the critical extraosseous and endosteal vessels. Results Angiographic imaging of 10 specimens demonstrated that this flap dissection preserves the nutrient endosteal supply to the humeral, radial, and ulnar diaphysis, in addition to the critical extraosseous arterial structures perfusing the elbow joint and periarticular tissues. From proximal to distal, these arteries are the musculoperiosteal radial, posterior branch of the radial collateral, inferior ulnar collateral, recurrent interosseous, radial recurrent, and the anterior and the posterior ulnar recurrent. Conclusions Vascularized composite allotransplantation of the elbow joint holds promise as a motion and function preserving option for young, high-demand patients with a sensate and functional hand, who would otherwise be limited by the restrictions of total elbow arthroplasty or fusion. In this study, we propose a flap design and technique for harvest and also offered vascular imaging-based evidence that this flap is adequately vascularized.

Background Peripheral nerve damage resulting in pain, loss of sensation, or motor function may necessitate a reconstruction with a bridging material. The RANGER® Registry was designed to evaluate outcomes following nerve repair with processed nerve allograft (Avance® Nerve Graft; Axogen; Alachua, FL). Here we report on the results from the largest peripheral nerve registry to‐date. Methods This multicenter IRB‐approved registry study collected data from patients repaired with processed nerve allograft (PNA). Sites followed their own standard of care for patient treatment and follow‐up. Data were assessed for meaningful recovery, defined as ≥S3/M3 to remain consistent with previously published results, and comparisons were made to reference literature. Results The study included 385 subjects and 624 nerve repairs. Overall, 82% meaningful recovery (MR) was achieved across sensory, mixed, and motor nerve repairs up to gaps of 70 mm. No related adverse events were reported. There were no significant differences in MR across the nerve type, age, time‐to‐repair, and smoking status subgroups in the upper extremity (p > .05). Significant differences were noted by the mechanism of injury subgroups between complex injures (74%) as compared to lacerations (85%) or neuroma resections (94%) (p = .03) and by gap length between the

Breast cancer affects about one in eight women over the course of her lifetime. Occult breast cancer, in which primary breast cancer is detected without evidence of disease in the breast itself, comprises up to 1% of new diagnoses; this is typically detected from abnormal axillary lymph nodes, and distant metastases are rare. Here, we present an unusual case of occult breast cancer presenting as upper extremity pain, edema, and weakness, with a metastatic mass to the brachial plexus being the only site of disease.

This article reviews the electrodiagnosis of brachial plexus injury, factors that predict outcome, the utility electrodiagnostic evaluation of potential nerve donors, and commonly used surgical interventions. Electrodiagnostic evaluation begins with a detailed understanding of brachial plexus anatomy and uses a complement of motor and sensory nerve conduction studies and needle electromyography to determine the location of injury and predict severity. Several factors are used to predict prognosis. In injuries with poor prognosis, surgical intervention is indicated. Nerve transfers are increasingly employed to improve functional outcomes. Electrodiagnosis is key to evaluating the viability of potential nerve donors.

Vascularized toe joint transfer for finger proximal interphalangeal joint reconstruction can result in sub-optimal arc of motion and extension lag due to inappropriate intercalated bony segment length. We investigated the impact of intercalated segment length on passive arc of motion and extension lag of the reconstructed proximal interphalangeal joint. Cadaveric intercalated joint grafts were harvested from lesser toes and transferred to cadaveric fingers. The pre-determined finger proximal interphalangeal joint defect size was 2 cm. Three different intercalated segment lengths were inserted and resulting proximal interphalangeal joint arc of motion and extension lag were measured. The average arc of motion of finger proximal interphalangeal joints was 81° and 54° for toe proximal interphalangeal joints. Long intercalated segments had an average arc of motion of 30° with 32° extension lag. Equal-length intercalated segments had an average 49° arc of motion with 15° extension lag. Short intercalated segments had an average arc of motion of 71° with 8° extension lag. Shorter intercalated segments provide the greatest reduction in extension lag.

Problem presented Sarcomatoid carcinoma (SaCa) is a rare variant of squamous cell carcinoma (SCC) with sarcomatoid features. This study investigated the clinical presentation and outcomes of head and neck SaCa. In addition, reconstructive outcome for a subset of patients was also evaluated. Studies undertaken Seventy-eight SaCa cases including 72 men and 6 women were identified from 13,777 head and neck SCC cases. Clinical outcomes were evaluated based on locoregional control, distant metastases, and multivariate analyses. Reconstructive outcome was evaluated by flap survival rate. Result Of the 78 cases, 71% (55) of cases were located in the oral mucosa; 64% (50) of patients were classified as T3 or T4 at the time of diagnosis. The 5-year survival was only 16%. Multivariate analysis revealed better outcomes only when the patient had a history of previous SCC. Forty-five patients underwent flap reconstruction, with 98% flap survival rate but the functional result varied because of the inevitable adjuvant radiotherapy and advanced stage of tumor. Conclusions Sarcomatoid carcinoma is a different entity from the conventional SCC of the head and neck. Sarcomatoid carcinoma carries a poorer prognosis despite aggressive surgical intervention and concurrent adjuvant therapies. It remains a great challenge for clinical oncologists, and the optimal treatment strategy requires further studies. Free flap is still preferred for defect reconstruction but the design should be simplified to avoid complications.

From a recent systemic review, vascularized toe proximal interphalangeal joint (PIPJ) transfer achieved an average arc of motion (AOM) of merely 37 degrees for finger PIPJ reconstruction. Despite the technical refinement over the past 3 decades, the resulting active motion of the reconstructed joint remains unpredictable and often fraught with extension lag. The technique for vascularized toe PIPJ transfer at our institute has evolved over the years to its current state, with simultaneous extensor mechanism reconstruction being a major component. During the transfer, the quality of extensor tendons on the recipient finger and donor toe are carefully evaluated. If the central slip of finger extensor is destroyed but the quality of lateral bands is adequate, centralization of lateral bands overlying the transferred PIPJ is performed. If there is acceptable central slip remnant at the proximal phalanx level, modified Stack procedure is performed for central slip reconstruction while leaving the lateral bands in continuity. If both lateral bands are poor, modified Stack procedure is performed unless the central tendon of the toe is strong enough to extend the PIPJ. From November 2008 to October 2010, 7 joints were transferred with this modified technique. The average follow-up was 18.2 months. The average active AOM of the transferred PIPJ was 56.4 degrees. The average extension lag of the toe PIPJ was 10.7 and 16.4 degrees before and after the transfer, respectively. Simultaneous reconstruction of extensor mechanism decreases the extension lag without sacrificing AOM of the transferred PIPJ.

Hand-arm vibration syndrome (HAVS) is a debilitating sequela of neurological and vascular injuries caused by prolonged occupational exposure to hand-transmitted vibration. Our previous study demonstrated that short-term exposure to vibration can induce vasoconstriction and endothelial cell damage in the ventral artery of the rat's tail. The present study investigated whether pretreatment with D-4F, an apolipoprotein A-1 mimetic with known anti-oxidant and vasodilatory properties, prevents vibration-induced vasoconstriction, endothelial cell injury, and protein nitration. Rats were injected intraperitoneally with 3 mg/kg D-4F at 1 h before vibration of the tails for 4 h/day at 60 Hz, 49 m/s2 r.m.s. acceleration for either 1 or 3 days. Vibration-induced endothelial cell damage was examined by light microscopy and nitrotyrosine immunoreactivity (a marker for free radical production). One and 3-day vibration produced vasoconstriction and increased nitrotyrosine. Preemptive treatment with D-4F prevented these negative changes. These findings suggest that D-4F may be useful in the prevention of HAVS.

The regions of the body have cortical and subcortical representation in proportion to their degree of innervation. The rat forepaw has been studied extensively in recent years using functional magnetic resonance imaging (fMRI), typically by stimulation using electrodes directly inserted into the skin of the forepaw. Here we stimulate the nerve directly using surgically implanted electrodes. A major distinction is that stimulation of the skin of the forepaw is mostly sensory, whereas direct nerve stimulation reveals not only the sensory system but also deep brain structures associated with motor activity. In this article, we seek to define both the motor and sensory cortical and subcortical representations associated with the four major nerves of the rodent upper extremity. We electrically stimulated each nerve (median, ulnar, radial, and musculocutaneous) during fMRI acquisition using a 9.4-T Bruker scanner (Bruker BioSpin, Billerica, MA). A current level of 0.5 to 1.0 mA and a frequency of 5 Hz were used while keeping the duration constant. A distinct pattern of cortical activation was found for each nerve that can be correlated with known sensorimotor afferent and efferent pathways to the rat forepaw. This direct nerve stimulation rat model can provide insight into peripheral nerve injury.

Purpose Ideal tendon repair materials combine minimal donor-site morbidity and ready availability with excellent healing and postoperative function. Bioengineered porcine small-intestinal submucosa (SIS) was compared with tendon autografts as a potential human flexor tendon graft substitute. Methods Rabbit zone II flexor digitorum profundus segments were excised in 40 rabbits. Randomized tendon repair consisted of either interposition reversed autograft or SIS, passed beneath the A2 and A4 pulleys. Forepaws were statically splinted for 3 weeks followed by unrestricted motion. Animals were killed at 7, 14, 28, and 56 days. Specimens were analyzed for hydroxyproline content (absorption spectroscopy) and tensile strength. Hematoxylin-eosin and Movat-stained sections of the central graft and distal repair site were semiquantitatively scored for total cellularity, inflammatory cell content, foreign-body reaction, vascularity, mature collagen content, and new collagen deposition. Transforming growth factor-β (TGF-β1) and TGF-β1 receptor immunostaining was performed. Results At week 1, SIS hydroxyproline content was significantly reduced compared with autograft hydroxyproline content. However, week 2 SIS hydroxyproline content increased to equivalent values. Collagen deposition was evident in SIS by week 1 but negligible in autograft. More rapid total and inflammatory cell increases occurred in SIS by 4 weeks. A stronger early inflammatory reaction also occurred. More rapid SIS neovascularization occurred despite a greater foreign-body reaction. Small-intestinal submucosa vascularity was markedly greater at weeks 1 and 2 and equivalent thereafter. At week 4, SIS intrinsic tensile strength (suture removed) exceeded that of both autograft and suture material. Preoperative TGF-β1 immunostaining in SIS was less than that of autograft but greater during weeks 2 and 4. Conclusions Earlier neovascularization, increased TGF-β1 levels, and increased collagen deposition, along with greater intrinsic repair strength relative to both autograft and suture strength at week 4, make SIS a promising flexor tendon graft substitute. Future studies examining tendon excursion are planned.

Velopharyngeal incompetence is a complication following cleft palate surgery, with an incidence ranging from 5 to 38 percent following palatoplasty.1 It occurs when the velopharyngeal valving mechanism is incapable of complete closure to isolate the oropharynx from the nasopharynx during speech production. The anatomical components of the velopharynx are the velum (soft palate) and the three pharyngeal walls: posterior, right lateral, and left lateral. Velopharyngeal closure depends on three basic factors: (1) superior and posterior movement of the soft palate produced by the contraction of the levator veli palatini muscle, (2) medial movement of the lateral pharyngeal walls, and (3) bulging forward of the posterior pharyngeal wall, creating a Passavant's ridge to facilitate velopharyngeal closure. Both the levator veli palatini muscle and the soft palate play a major role in the pathogenesis of velopharyngeal incompetence. Dysfunction of the levator veli palatini muscle or shortness of the soft palate may cause velopharyngeal incompetence, yet treatment options are quite different. Therefore, accurate diagnosis is crucial. Procedures that rely on restoration of a functional levator sling require the presence of adequate levator musculature for reconstruction of the levator sling. When the diagnosis of velopharyngeal incompetence is confirmed, speech therapy is initiated. Should the patient fail to demonstrate sufficient improvement in nasality despite speech therapy, secondary surgical management to restore a competent velopharyngeal valving mechanism may be indicated. If it is possible to do so by restoration of the levator muscular sling, this may obviate the need for surgical alteration of the posterior or lateral pharyngeal walls as occurs during a pharyngeal flap or sphincter pharyngoplasty. Dynamic reconstruction of the levator sling can be accomplished using either a Furlow palatoplasty in patients with submucous cleft palate or postpalatoplasty velopharyngeal incompetence,2 or by palate re-repair in patients with postpalatoplasty velopharyngeal incompetence as advocated by Sommerlad and colleagues.3 However, should the levator mechanism be negligible or replaced with scar following prior surgery, attempting dynamic levator reconstruction would not result in a competent velopharyngeal valving mechanism, and pharyngeal flap or sphincter pharyngoplasty should be considered. Therefore, the ability to visualize different soft-tissue planes of the velopharynx and to visualize the muscular anatomy preoperatively become crucial when planning secondary surgical management of velopharyngeal incompetence. Current methods for functional visualization of the velopharynx are either invasive (nasendoscopy) or impart ionizing radiation (speech videofluoroscopy), and do not provide anatomical definition of palatal soft-tissue planes. In addition to its invasiveness, nasendoscopy allows only a single viewpoint (from a ventral and cephalad observation point) of the velum. Furthermore, both the passage of the endoscope itself and the local anesthetic agent used during scoping may affect speech. In contrast, although speech videofluoroscopy allows visualization of dynamic interaction (i.e., functional evaluation) of velopharyngeal structures from different angles, interpretation is difficult because of shadows introduced by the overlying structures. Moreover, relative proportion distortion is inevitable in speech videofluoroscopy because three-dimensional structures are converted into two-dimensional images. An ideal test that is noninvasive and does not impart ionizing radiation is not in widespread use for preoperative assessment of the velopharyngeal mechanism in children. Magnetic resonance imaging is noninvasive and poses no ionizing radiation hazard, and allows imaging of the velopharyngeal mechanism during limited speech production. Magnetic resonance imaging also allows anatomical assessment of soft-tissue planes involved in the velopharyngeal valving mechanism, which is not possible with other techniques currently in use. The major hurdle that prevents the widespread application of magnetic resonance imaging for functional evaluation of the velopharyngeal mechanism is poor image quality. To examine the function of the velopharyngeal mechanism during active phonation using magnetic resonance imaging, patients are instructed to sustain phonation of a chosen vowel or consonant during the image-acquisition process. Because most patients, especially children, are only able to sustain phonation for 15 to 20 seconds comfortably, image-acquisition time is limited. This in turn limits the resolution of the acquired image. Fortunately, magnetic resonance image quality is dependent not only on the length of acquisition time but also on the magnetic field strength and head coil design. By using more powerful magnetic resonance imaging scanners and better head coil design, improvement in magnetic resonance images is possible without increasing image-acquisition time. Previous magnetic resonance imaging studies involving functional evaluation of the velopharyngeal valving mechanism in children used magnetic resonance imaging scanners with a strength up to only 1.5 T.4–7 By using a 3.0-T magnetic resonance imaging scanner with a multichannel head coil, we hypothesize that the quality of the images acquired will be sufficient to allow functional evaluation of the velopharyngeal valving mechanism in children. Moreover, resolution of the images will allow delineation of palatal soft-tissue planes for surgical planning.

The response of the rat visual system to flashes of blue light has been studied by blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI). The BOLD temporal response is dependent on the number of flashes presented and demonstrates a refractory period that depends on flash frequency. Activated brain regions included the primary and secondary visual cortex, superior colliculus (SC), dorsal lateral geniculate (DLG), and lateral posterior nucleus (LP), which were found to exhibit differing temporal responses. To explain these differences, the BOLD neurovascular response function was modeled. A second-order differential equation was developed and solved numerically to arrive at region-specific response functions. Included in the model are the light input from the diode (duty cycle), a refractory period, a transient response following onset and cessation of stimulus, and a slow adjustment to changes in the average level of the signal. Constants in the differential equation were evaluated for each region by fitting the model to the experimental BOLD response from a single flash, and the equation was then solved for multiple flashes. The simulation mimics the major features of the data; however, remaining differences in the frequency dependence of the response between the cortical and subcortical regions were unexplained. We hypothesized that these discrepancies were due to regional-specific differences in neuronal response to flash frequency. To test this hypothesis, cortical visual evoked potentials (VEPs) were recorded using the same stimulation protocol as the fMRI. Cortical VEPs were more suppressed than subcortical VEPs as flash frequency increased, supporting our hypothesis. This is the first report that regional differences in neuronal activation to the same stimulus lead to differential BOLD activation.

Background Previous seawater studies found Vibrio species associated with morbidity, suggesting that seawater-contaminated wounds should be treated early. The purpose of this study was to identify common seawater pathogens and antibiotic sensitivities to provide empiric antibiotic therapy until patient-specific culture results are available. Methods Seasonal samples were collected from 25 Galveston beach locations and cultured. Colonies were identified and sensitivities were performed using MicroScan Positive and Negative Breakpoint Combo Panels. Results In the fall (28.3 degrees C), of 15 species isolated, the three most common isolates were Escherichia coli, Enterococcus faecium, and Klebsiella pneumoniae. Gram-negative isolates were sensitive to levofloxacin, lomefloxacin, and cefepime. Gram-positive isolates were sensitive to penicillin and ampicillin. In the winter (11.1 degrees C), of 14 species isolated, the three most common isolates were Enterobacter agglomerans, E. faecium, and E. coli. Gram-negative isolates were sensitive to levofloxacin, lomefloxacin, and cefepime. Most Gram-positive isolates were sensitive to vancomycin, levofloxacin, penicillin, and ampicillin. In the spring (26.6 degrees C), of 14 species isolated, the three most common isolates were E. coli, Bacillus species, and E. faecium. Gram-negative isolates were sensitive to levofloxacin, lomefloxacin, and cefepime. Most Gram-positive isolates were sensitive to penicillin, ampicillin, vancomycin, and levofloxacin. In the summer (29.7 degrees C), of 17 bacterial species isolated, the three most common isolates were Bacillus species, Enterobacter cloacae, and K. pneumoniae. Gram-negative isolates were sensitive to cefepime, lomefloxacin, and levofloxacin. Gram-positive isolates were sensitive to penicillin, ampicillin, vancomycin, levofloxacin, and chloramphenicol. Conclusions Cultured pathogens were sensitive to penicillin, ampicillin, or levofloxacin. The authors recommend a combination of penicillin or ampicillin with levofloxacin for empiric antibiotic coverage for seawater-contaminated injuries.

Regional-specific average time courses of spontaneous fluctuations in blood oxygen level dependent (BOLD) MRI contrast at 9.4T in lightly anesthetized resting rat brain are formed, and correlation coefficients between time course pairs are interpreted as measures of connectivity. A hierarchy of regional pairwise correlation coefficients (RPCCs) is observed, with the highest values found in the thalamus and cortex, both intra- and interhemisphere, and lower values between the cortex and thalamus. Independent sensory networks are distinguished by two methods: data driven, where task activation defines regions of interest (ROI), and hypothesis driven, where regions are defined by the rat histological atlas. Success in these studies is attributed in part to the use of medetomidine hydrochloride (Domitor) for anesthesia. Consistent results in two different rat-brain systems, the sensorimotor and visual, strongly support the hypothesis that resting-state BOLD fluctuations are conserved across mammalian species and can be used to map brain systems.

The current gold standard for the diagnosis and staging of hand-arm vibration syndrome (HAVS) is the Stockholm workshop scale, which is subjective and relies on the patient's recalling ability and honesty. Therefore, great potentials exist for diagnostic and staging errors. The purpose of this study is to determine if objective serum tests, such as levels of soluble thrombomodulin (sTM) and soluble intercellular adhesion molecule-1 (sICAM-1), may be used in the diagnosis and staging of HAVS. Twenty two nonsmokers were divided into a control group (n = 11) and a vibration group (n = 11). The control group included subjects without history of frequent vibrating tool use. The vibration group included construction workers with average vibrating tool use of 12.2 years. All were classified according to the Stockholm workshop scale (SN, sensorineural symptoms; V, vascular symptoms. SN0, no numbness; SN1, intermittent numbness; SN2, reduced sensory perception; SN3, reduced tactile discrimination; V0, no vasospasmic attacks; V1, intermittent vasospasm involving distal phalanges; V2, intermittent vasospasm extending to middle phalanges; V3, intermittent vasospasm extending to proximal phalanges; V4, skin atrophy/necrosis). All control subjects were SN0 V0. Seven out of 11 vibration subjects were SN1 V1, and 4 out of 11 were SN1 V2. A 10-cm(3) sample of venous blood was collected from each subject. The sTM and sICAM-1 levels were determined by enzyme-linked immunosorbent assay. The mean plasma sTM levels were as follows: control group = 2.93 +/- 0.47 ng/ml, and vibration group = 3.61 +/- 0.24 ng/ml. The mean plasma sICAM-1 levels were as follows: control group = 218.8 +/- 54.1 ng/ml, and vibration group = 300.3 +/- 53.2 ng/ml. The sTM and sICAM-1 differences between control and vibration groups were statistically significant (p0.0002 and p0.001, respectively). When reference ranges provided by Hemostasis Reference Lab were used as cut-off values, all sTM and sICAM-1 levels were within range, except three vibration individuals (27%) who had sICAM-1 levels greater than the reference range. This was not statistically significant (p = 0.08). When subjects were compared based on the Stockholm workshop scale, mean plasma sTM levels were SN0 V0 group = 2.93 +/- 0.47 ng/ml, SN1 V1 group = 3.59 +/- 0.25 ng/ml, and SN1 V2 group = 3.65 +/- 0.27 ng/ml, and mean plasma sICAM-1 levels were SN0 V0 = 219 +/- 54.1 ng/ml, SN1 V1 = 275 +/- 33.5 ng/ml, and SN1 V2 = 345 +/- 54.6 ng/ml. The difference in sTM level among the three groups was statistically significant (p0.001). The difference in sICAM-1 level among the three groups was also statistically significant (p0.002). The sTM and sICAM-1 levels are statistically higher in subjects with HAVS, with levels proportional to the disease severity. However, large population studies are needed to determine the "real-life" standard reference ranges for sTM and sICAM-1.

It is well understood that the different regions of the body have cortical representations in proportion to the degree of innervation. Our current understanding of the rat upper extremity has been enhanced using functional MRI (fMRI), but these studies are often limited to the rat forepaw. The purpose of this study is to describe a new technique that allows us to refine the sensory and motor representations in the cerebral cortex by surgically implanting electrodes on the major nerves of the rat upper extremity and providing direct electrical nerve stimulation while acquiring fMRI images. This technique was used to stimulate the ulnar, median, radial, and musculocutaneous nerves in the rat upper extremity using four different stimulation sequences that varied in frequency (5 Hz vs. 10 Hz) and current (0.5 mA vs. 1.0 mA). A distinct pattern of cortical activation was found for each nerve. The higher stimulation current resulted in a dramatic increase in the level of cortical activation. The higher stimulation frequency resulted in both increases and attenuation of cortical activation in different regions of the brain, depending on which nerve was stimulated.

Peripheral nerves traverse through different soft tissue compartments in the upper and lower extremities via specific anatomical tunnels, where they are susceptible to entrapment. Common sites in the upper extremity include carpal tunnel, cubital tunnel and radial tunnel. Common sites in the lower extremity include piriformis, fibular neck, and tarsal tunnel. Compressive peripheral neuropathy can develop in these sites, and are amenable for surgical decompression.

Lateral gastrocnemius muscle flaps are reliable flaps routinely used to cover defects in the lower thigh, the knee, and the upper third of the tibia. Peroneal neuropathy following lateral gastrocnemius flap has been described previously and mostly attributed to intraoperative nerve injury. However, compression of the nerve by the flap itself has not been reported. A 56-year-old female developed right common peroneal nerve palsy 10 months after a lateral gastrocnemius flap rotation for knee prosthesis coverage. Surgical exploration found a common peroneal nerve neuroma under a compressive band formed by the lateral fascial edge of the rotated gastrocnemius muscle. The motor nerve of the flap was not denervated. When stimulated, muscle contracted and compressed the common peroneal nerve underneath. Excision of the lateral fascia and selective motor denervation were performed. Postoperatively, the patient's symptoms improved. To prevent compressive common peroneal neuropathy from lateral gastrocnemius rotational flaps, we recommend fascial excision from the lateral aspect of the muscle and selective motor denervation.

Irregularly shaped and three-dimensional soft-tissue defects in the extremities are difficult to cover precisely and efficiently. One strategy is to use the anterolateral thigh flap with two perforators and split the flap into two subunits based on separate perforators. The subunits can be rearranged into various geometric configurations to cover defects with nonelliptical shapes. Such a strategy emphasizes harvesting an elliptical anterolateral thigh flap with a narrower width to allow for primary closure in most cases. This avoids the need for skin grafting and reduces donor-site morbidity.From 2002 to 2010, 15 patients with upper and lower limb defects were treated with split anterolateral thigh flaps. There were nine male patients and six female patients. The mean age of the patients was 40.6 years (range, 18 to 64 years). The shape of each defect was classified as arrow-shape, hourglass-shape, triangular, or three-dimensional.All split flaps (n = 31) survived without vascular problems. Two split flaps demonstrated margin necrosis without critical structure exposure. Only one donor site needed skin grafting. All other donor sites were closed primarily.The split anterolateral thigh flap is an effective strategy for covering irregular and three-dimensional defects in the extremities. It allows efficient use of the harvested flap and minimizes trimming and discarding unused flap parts. This decreases the area of skin graft needed for donor-site coverage and may even be able to achieve primary closure.Therapeutic, V.

Prolonged hand-transmitted vibration exposure in the workplace has been recognized for almost a century to cause neurodegenerative and vasospastic disease. Persistence of the diseased state for years after cessation of tool use is of grave concern. To understand persistence of vibration injury, the present study examined recovery of nerve conduction velocity and structural damage of myelinated axons in a rat tail vibration model. Both 7 and 14 days of vibration (4 h/day) decreased conduction velocity. The decrease correlated directly with the increased percentage of disrupted myelinated axons. The total number of myelinated axons was unchanged. During 2 months of recovery, conduction velocity returned to control level after 7-day vibration but remained decreased after 14-day vibration. The rat tail model provides insight into understanding the persistence of neural deficits in hand–arm vibration syndrome. Muscle Nerve, 2009