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The distal radioulnar joint is a complex anatomic structure that allows for a combination of rotation and translation with extrinsic and intrinsic stabilizers that maintain stability through a delicate equilibrium. Traumatic, congenital, inflammatory, and degenerative processes can disturb this sensitive balance, resulting in distal radioulnar joint arthritis. We discuss the joint's anatomy and biomechanics and the clinical approach to the patient. We review the surgical treatment options, expected outcomes, and their shortcomings. Selecting the best surgical intervention often means choosing the procedure with the set of complications and limitations best suited for the specific patient.

INTRODUCTION: Active learning methods have accumulated popularity due to improved results in knowledge acquisition as opposed to passive learning methods. For surgical resident physicians with limited training opportunities outside of the operating room due to time constraints, virtual reality (VR) is a relatively inexpensive and time-efficient active training method for procurement of surgical skills. We conducted a simulated intramedullary nailing (IMN) of a tibia to demonstrate VR training programs as a more effective modality of learning orthopaedic surgical techniques compared to passive learning tools such as a standard guide (SG) through trained novice medical students performing a SawBones simulation of intramedullary nail fixation. MATERIALS AND METHODS: First and second-year medical students without prior experience of procedure were recruited and randomized to SG or VR training. Participants were observed performing simulated tibia IMN procedure immediately after training and evaluated by a blinded attending surgeon using procedure-specific checklist and 5-point global assessment scale. Participants returned after 2-weeks for repeat training and evaluation. RESULTS: 20 participants were recruited and randomized into VR (n=10) and SG (n=10) groups. All 20 participants completed the first phase and 17 completed the second phase of the study. Aggregate global assessment scores were significantly higher for VR than SG group (17.5 vs. 7.5, p

Ganglion cysts represent the most common soft-tissue mass in the hand and wrist. Ganglion cysts are most commonly encountered at the dorsal or volar aspects of the wrist, although cysts may arise from the flexor tendon sheath, interphalangeal joint, and extensor tendons. Intraosseous and intraneural ganglion cysts have also been described. Diagnosis of ganglion cysts relies primarily on history and physical examination. Transillumination and aspiration of masses may be useful adjuncts to diagnosis. Imaging such as radiography and ultrasonography may be indicated to evaluate for associated conditions, such as degenerative joint disease, or to rule out a solid or heterogeneous mass. Advanced imaging such as MRI is generally reserved for patients in whom occult ganglions, intraosseous ganglions, or solid tumors, including sarcoma, remain a concern. Treatment of ganglion cysts includes observation, aspiration or puncture with possible corticosteroid injection, and surgical excision. Nonsurgical management may result in cyst resolution in over 50% of patients. Surgical excision is associated with recurrence rates of 7% to 39%. Advances in surgical techniques have allowed surgeons to conduct arthroscopic ganglion excision, with recurrence rates similar to those of open management. This study highlights the advances in diagnosis, treatment, and outcomes that have taken place over the past 2 decades for this common condition affecting the hand and wrist in the adult population.

Implants and their technological advances have been a critical component of musculoskeletal care for almost a century. Modern implants are designed to enhance bone ingrowth, promote soft-tissue healing, and prevent infection. Porous metals and short-stem fixation devices have rendered previously unreconstructable bony deficits reconstructable. Stem cells, growth factors, and novel biocompatible compounds have been designed to promote and enhance soft tissue attachment to implants. Antimicrobial modifications have been engineered onto implants to deter bacterial attachment, and innovative surface modifications and eluting technologies may be in our near future. Yet, given the enormous economic pressures in orthopaedics, marketing claims of innovation often exceed scientific accomplishment. Vigilance is thus required in distinguishing transformational discovery from unsubstantiated claims.

Purpose: Current guidelines recommend that open reduction internal fixation (ORIF) for distal radius fractures (DRFs) be performed within 4 weeks of injury. Delayed DRF management (4 weeks or more) is traditionally subject to corrective osteotomy. We report a 5-year single-surgeon series of delayed DRFs that were treated by ORIF rather than osteotomy. Methods: We performed a retrospective review on all patients admitted to a single tertiary care center with a DRF requiring ORIF (2007–2012). Institutional review board approval was obtained. Patients were divided into an early group (EG) (surgery less than 4 weeks after injury) and delayed group (DG) (surgery after 4 or more weeks). Data collected included demographics, injury pattern, intraoperative parameters, and pre- and postoperative x-ray findings. Subjective and objective functional data were determined using a Disabilities of the Arm, Shoulder, and Hand questionnaire score and Mayo Wrist Score. Results: A total of 171 patients (EG = 54; DG = 117) underwent ORIF from 2007 to 2012 and met inclusion criteria. Both groups had similar age, gender, and racial demographics. Of these, 117 patients in the delayed group underwent ORIFs at 40 ± 13.9 days (range, 28–146 days) after injury. Preoperative fracture patterns were radiographically equivalent. A dorsal approach was required more frequently in the EG (7.4%) compared with DG (1.1%). The Orbay maneuver was performed at a significantly higher rate in the DG (55.8%) compared with the EG (38.8%). Blood loss, tourniquet times, intraoperative complications, radiographic parameters, articular incongruency rates, and Disabilities of the Arm, Shoulder, and Hand score, and Mayo Wrist Score were not statistically significant between groups. Conclusions: No significant differences were found in intraoperative technique, operative time, postoperative radiographs, and subjective outcome measures in patients treated with early versus late ORIF. Despite the current belief that primary ORIF in delayed DRF is technically impossible and warrants an osteotomy, our series indicates that ORIF is indeed a viable option in DRFs as late as 5 months after injury. Type of study/level of evidence: Therapeutic IV Key words: delayed internal fixation, distal radius fractures

Implant-associated infections are challenging to diagnose and treat. Fluorescent probes have been heralded as a technologic advancement that can improve our ability to non-invasively identify infecting organisms, as well as guide the inexact procedure of surgical debridement. This study’s purpose was to compare two fluorescent probes for their ability to localize Staphylococcus aureus biofilm infections on spinal implants utilizing noninvasive optical imaging, then assessing the broader applicability of the more successful probe in other infection animal models. This was followed by real-time, fluorescence image-guided surgery to facilitate debridement of infected tissue. The two probe candidates, a labelled antibiotic that targets peptidoglycan (Vanco-800CW), and the other, a labelled antibody targeting the immunodominant Staphylococcal antigen A (1D9-680), were injected into mice with spine implant infections. Mice were then imaged noninvasively with near infrared fluorescent imaging at wavelengths corresponding to the two probe candidates. Both probes localized to the infection, with the 1D9-680 probe showing greater fidelity over time. The 1D9-680 probe was then tested in mouse models of shoulder implant and allograft infection, demonstrating its broader applicability. Finally, an image-guided surgery system which superimposes fluorescent signals over analog, real-time, tissue images was employed to facilitate debridement of fluorescent-labelled bacteria.

Extremity reconstruction surgery is increasingly performed rather than amputation for patients with large-segment pathologic bone loss. Debate persists as to the optimal void filler for this “limb salvage” surgery, whether metal or allograft bone. Clinicians focus on optimizing important functional gains for patients, and the risk of devastating implant infection has been thought to be similar regardless of implant material. Recent insights into infection pathophysiology are challenging this equipoise, however, with both basic science data suggesting a novel mechanism of infection of Staphylococcus aureus (the most common infecting agent) into the host lacunar–canaliculi network, and also clinical data revealing a higher rate of infection of allograft over metal. The current translational study was therefore developed to bridge the gap between these insights in a longitudinal murine model of infection of allograft bone and metal. Real-time Staphylococci infection characteristics were quantified in cortical bone vs metal, and both microarchitecture of host implant and presence of host immune response were assessed. An orders-of-magnitude higher bacterial burden was established in cortical allograft bone over both metal and cancellous bone. The establishment of immune-evading microabscesses was confirmed in both cortical allograft haversian canal and the submicron canaliculi network in an additional model of mouse femur bone infection. These study results reveal a mechanism by which Staphylococci evasion of host immunity is possible, contributing to elevated risks of infection in cortical bone. The presence of this local infection reservoir imparts massive clinical implications that may alter the current paradigm of osteomyelitis and bulk allograft infection treatment.

Background: Animal models are used to guide management of periprosthetic implant infections. No adequate model exists for periprosthetic shoulder infections, and clinicians thus have no preclinical tools to assess potential therapeutics. We hypothesize that it is possible to establish a mouse model of shoulder implant infection (SII) that allows noninvasive, longitudinal tracking of biofilm and host response through in vivo optical imaging. The model may then be employed to validate a targeting probe (1D9-680) with clinical translation potential for diagnosing infection and image-guided debridement.Methods: A surgical implant was press-fit into the proximal humerus of c57BL/6J mice and inoculated with 2 mu L of 1 x 10(3) (e3), or 1 x 10(4) (e4), colony-forming units (CFUs) of bioluminescent Staphylococcus aureus Xen-36. The control group received 2 mu L sterile saline. Bacterial activity was monitored in vivo over 42 days, directly (bioluminescence) and indirectly (targeting probe). Weekly radiographs assessed implant loosening. CFU harvests, confocal microscopy, and histology were performed.Results: Both inoculated groups established chronic infections. CFUs on postoperative day (POD) 42 were increased in the infected groups compared with the sterile group (P Discussion: Given bone destruction in the e4 group, a longitudinal, noninvasive mouse model of SII and chronic osteolysis was produced using e3 of S aureus Xen-36, mimicking clinical presentations of chronic SII.Conclusion: The development of this model provides a foundation to study new therapeutics, interventions, and host modifications. (C) 2019 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.

Spine implant infections portend poor outcomes as diagnosis is challenging and surgical eradication is at odds with mechanical spinal stability. The purpose of this method is to describe a novel mouse model of spinal implant infection (SII) that was created to provide an inexpensive, rapid, and accurate in vivo tool to test potential therapeutics and treatment strategies for spinal implant infections. In this method, we present a model of posterior-approach spinal surgery in which a stainless-steel k-wire is transfixed into the L4 spinous process of 12-week old C57BL/6J wild-type mice and inoculated with 1 × 10(3) CFU of a bioluminescent strain of Staphylococcus aureus Xen36 bacteria. Mice are then longitudinally imaged for bioluminescence in vivo on post-operative days 0, 1, 3, 5, 7, 10, 14, 18, 21, 25, 28, and 35. Bioluminescence imaging (BLI) signals from a standardized field of view are quantified to measure in vivo bacterial burden. To quantify bacteria adhering to implants and peri-implant tissue, mice are euthanized and the implant and surrounding soft tissue are harvested. Bacteria are detached from the implant by sonication, cultured overnight and then colony forming units (CFUs) are counted. The results acquired from this method include longitudinal bacterial counts as measured by in vivo S. aureus bioluminescence (mean maximum flux) and CFU counts following euthanasia. While prior animal models of instrumented spine infection have involved invasive, ex vivo tissue analysis, the mouse model of SII presented in this paper leverages noninvasive, real time in vivo optical imaging of bioluminescent bacteria to replace static tissue study. Applications of the model are broad and may include utilizing alternative bioluminescent bacterial strains, incorporating other types of genetically engineered mice to contemporaneously study host immune response, and evaluating current or investigating new diagnostic and therapeutic modalities such as antibiotics or implant coatings.

Author(s): Henderson, Eric R; Keeney, Benjamin J; Husson, Emily G; Bernthal, Nicholas M; Ji, Tao; Pala, Elisa; Funovics, Philipp T; Groundland, John S; Lozano-Calderon, Santiago; Puchner, Stephan; Zoller, Stephen D; Ruggieri, Pietro; Windhager, Reinhard; Guo, Wei; Hornicek, Francis J; Letson, G Douglas; Temple, H Thomas | Abstract: BackgroundThere is scant evidence to guide decision-making for patients considering total femoral replacement (TFR). We aimed to identify the indication, patient, disease, and surgical technique-related factors associated with failure. We hypothesized that failure occurs more frequently in the setting of revision surgical procedures, with infection as the predominant failure mode.MethodsWe performed a retrospective cohort study of patients receiving total femoral endoprostheses for oncological and revision arthroplasty indications; 166 patients met these criteria. Our primary independent variable of interest was TFR for a revision indication (arthroplasty or limb salvage); the primary outcome was failure. Analyses were performed for patient variables (age, sex, diagnosis group, indication), implant variables (model, decade, length, materials), and treatment variables. We analyzed TFR failures with respect to patient factors, operative technique, and time to failure. We conducted bivariate logistic regressions predicting failure and used a multivariate model containing variables showing bivariate associations with failure.ResultsForty-four patients (27%) had treatment failure. Failure occurred in 24 (23%) of 105 primary TFRs and in 20 (33%) of 61 revision TFRs; the difference was not significant (p = 0.134) in bivariate analysis but was significant (p = 0.044) in multivariate analysis. The mean age at the time of TFR was 37 years in the primary group and 51 years in the revision group (p = 0.0006). Of the patients who had mechanical failure, none had reoccurrence of their original failure mode, whereas all 8 patients from the nonmechanical cohort had reoccurrence of the original failure mode; this difference was significant (p = 0.0001).ConclusionsTFR has a high failure rate and a propensity for deep infection, especially in the setting of revision indications and prior infection. All failed TFRs performed for revision indications for infection or local recurrence failed by reoccurrence of the original failure mode and resulted in amputation.Level of evidenceTherapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Author(s): Ishmael, Chad R; Hsiue, Peter P; Zoller, Stephen D; Wang, Pengcheng; Hori, Kellyn R; Gatto, Jonathan D; Li, Rebecca; Jeffcoat, Devon M; Johnson, Eric E; Bernthal, Nicholas M | Abstract: BackgroundThere is a new method of transportation that started in our community in late 2017- rideshare electric scooters (e-scooters). These scooters have proven immensely popular and can now be found in many cities around the world. Despite the pervasiveness of e-scooters, their associated injury patterns are poorly understood. The purpose of this study was to describe our department's experience at the epicenter of the e-scooter phenomenon that is sweeping the globe and to characterize operative orthopaedic injuries that are related to e-scooter accidents.MethodsWe performed a retrospective chart review of all of the operative orthopaedic cases and trauma consults at 2 trauma centers (a level-I center and a level-II center) between September 2017 and August 2019. We identified all operative injuries in which the cause of injury was an e-scooter accident. Data that included demographics, mechanism of injury, diagnosis, and treatment were collected.ResultsSeventy-five operative injuries were identified in 73 patients during the study period. The mean patient age was 35.4 years (range, 14 to 74 years), and the median age was 32 years. There were 4 pediatric patients (14, 15, 15, and 17 years old). Thirty-two patients (43.8%) sustained upper-extremity injuries, and 42 patients (57.5%) sustained lower-extremity injuries; 1 of these patients had both upper and lower-extremity injuries. Nine patients (12.3%) had open fractures. There were 7 hip fractures in patients with an average age of 42.4 years (range, 28 to 68 years). Seventy-one (97.3%) of 73 patients were e-scooter riders, and 2 (2.7%) were pedestrians who were struck by e-scooter riders.ConclusionsE-scooters can cause serious injury. Seventy-three patients required operative treatment in just the first 2 years of e-scooter use in our community. Operative injuries occurred throughout the skeletal system, and several were injuries that are typically associated with high-energy trauma. Although, as a rule, e-scooter use is limited to adults and banned in high pedestrian-traffic areas in our city, the inclusion of 4 underage riders and 2 pedestrians in our cohort suggests that these rules are not always followed. As e-scooters continue to increase in popularity, additional steps should be taken to regulate their use and protect riders and the public.

The case of a child is described who was treated for distal femoral osteosarcoma with chemotherapy, removal of the distal femoral bone, and the implantation of a series of distal femoral endoprostheses with hinged tibial components. The design of this modular prosthesis allows for expansion during the years that the bones continue to grow. The tissues from nine surgical procedures were examined, along with one tibial bearing and axle component. Wear debris was noted in variable amounts in nearly all of the tissues but solid corrosion products from the modular junctions were abundant only in the last revision tissues. The amount of wear and corrosion of the explants seemed inconsistent with the size and amount of corrosion products in the tissues. The source of the debris is likely to be in the modular connections that were not revised.

Instrumentation with pedicle screw constructs is used to achieve stabilization during posterolateral lumbar fusion (PLF) in patients with various lumbosacral spinal disorders. Neurologic injuries from iatrogenic pedicle wall breaches during screw placement are known complications of PLFs with an estimated risk of 0.8% to 6.1%.1–3 To minimize the risk of these complications, intraoperative neuromonitoring (ION) is often used. ION has been used clinically since the 1970s to detect injury to the neural elements.4 Electromyography (EMG), triggered or spontaneous, is a form of ION that monitors peripheral muscle activity from nerve root stimulation from pedicle screw malposition. Spontaneous EMG continuously monitors peripheral nerve roots responsible for muscle innervation using electrodes placed in the muscles corresponding to the level(s) of interest. Spikes, bursts, or trains of activity during surgery may indicate pulling, compression, or stretching of nerves. Triggered EMG helps identify a pedicle wall breach by measuring the amplitude of current intensity required to trigger a nerve root through pedicle screw stimulation, which has been shown to be

Intramedullary fixation of proximal tibia fractures remains a challenging surgical technique, with malalignment reported as high as 84%. The pull from the extensor mechanism, the hamstring and iliotibial band, in addition to the lack of endosteal fit from the nail, has made surgical fixation of these fractures difficult. Commonly held principles to reduce angular deformity include ensuring adequate imaging, obtaining an optimal start and trajectory for the implant, and obtaining and maintaining a reduction throughout the duration of the procedure. Some adjunctive techniques to assist in the application of these principles include use of a semiextended technique, clamping, blocking screws/wires, and unicortical plates. Understanding the challenges involved in intramedullary nailing of proximal tibia fractures and considering a wide array of techniques in the orthopaedic surgeon's armamentarium to combat these challenges is important.

Author(s): Hegde, Vishal; Park, Howard Y; Dworsky, Erik; Zoller, Stephen D; Xi, Weixian; Johansen, Daniel O; Loftin, Amanda H; Hamad, Christopher D; Segura, Tatiana; Bernthal, Nicholas M | Abstract: Study designA controlled, interventional animal study.ObjectiveSpinal implant infection (SII) is a devastating complication. The objective of this study was to evaluate the efficacy of a novel implant coating that has both a passive antibiotic elution and an active-release mechanism triggered in the presence of bacteria, using an in vivo mouse model of SII.Summary of background dataCurrent methods to minimize the frequency of SII include local antibiotic therapy (vancomycin powder), betadine irrigation, silver nanoparticles, and passive release from antibiotic-loaded poly(methyl methacrylate) cement beads, all of which have notable weaknesses. A novel implant coating has been developed to address some of these limitations but has not been tested in the environment of a SII.MethodsA biodegradable coating using branched poly(ethylene glycol)-poly(propylene sulfide) (PEG-PPS) polymer was designed to deliver antibiotics. The in vivo performance of this coating was tested in the delivery of either vancomycin or tigecycline in a previously established mouse model of SII. Noninvasive bioluminescence imaging was used to quantify the bacterial burden, and implant sonication was used to determine bacterial colony-forming units (CFUs) from the implant and surrounding bone and soft tissue.ResultsThe PEG-PPS-vancomycin coating significantly lowered the infection burden from postoperative day 3 onwards (P l 0.05), whereas PEG-PPS-tigecycline only decreased the infection on postoperative day 5 to 10 (P l 0.05). CFUs were lower on PEG-PPS-vancomycin pins than PEG-PPS-tigecycline and PEG-PPS pins alone on both the implants (2.4 × 10, 8.5 × 10, and 1.0 × 10 CFUs, respectively) and surrounding bone and soft tissue (1.3 × 10, 4.8 × 10, and 5.4 × 10 CFUs, respectively) (P l 0.05).ConclusionThe biodegradable PEG-PPS coating demonstrates promise in decreasing bacterial burden and preventing SII. The vancomycin coating outperformed the tigecycline coating in this model compared to prior work in arthroplasty models, highlighting the uniqueness of the paraspinal infection microenvironment.Level of evidenceN/A.

Spine implant infections portend disastrous outcomes, as diagnosis is challenging and surgical eradication is at odds with mechanical spinal stability. Current imaging modalities can detect anatomical alterations and anomalies but cannot differentiate between infection and aseptic loosening, diagnose specific pathogens, or delineate the extent of an infection. Herein, a fully human monoclonal antibody 1D9, recognizing the immunodominant staphylococcal antigen A on the surface of Staphylococcus aureus, was assessed as a nuclear and fluorescent imaging probe in a preclinical model of S. aureus spinal implant infection, utilizing bioluminescently labeled bacteria to confirm the specificity and sensitivity of this targeting. Postoperative mice were administered 1D9 probe dual labeled with 89-zirconium (89Zr) and a bars represent SEM dye (NIR680) (89Zr-NIR680-1D9), and PET-CT and in vivo fluorescence and bioluminescence imaging were performed. The 89Zr-NIR680-1D9 probe accurately diagnosed both acute and subacute implant infection and permitted fluorescent image-guided surgery for selective debridement of infected tissue. Therefore, a single probe could noninvasively diagnose an infection and facilitate image-guided surgery to improve the clinical management of implant infections.

IntroductionAlthough a variety of agencies have attempted to evaluate the academic achievements of orthopaedic surgery academic centers, most use opaque criteria that are difficult to interpret and do not provide clear targets for improvement. This study leverages a weighted algorithm using objective measurements that has been linked to academic achievement to attempt to provide a comprehensive assessment of scholarly accomplishment for orthopaedic surgery academic centers.MethodsWe examined full-time faculty at 138 US orthopaedic surgery academic centers; part-time or volunteer faculty were excluded. Five metrics of academic achievement were assessed: National Institutes of Health funding (2013), number of publications, Hirschberg-index (ie, a metric of impact of publications), leadership positions held in orthopaedic surgery societies, and editorial board positions of top orthopaedic and subspecialty journals. Academic programs were given a score for every category, and the algorithm was used to calculate an overall score of academic achievement for each program.ResultsThe five most academically productive programs were Washington University in St. Louis, Hospital for Special Surgery, Mayo Clinic, University of Pennsylvania, and Thomas Jefferson University.ConclusionThis algorithm may provide faculty with an assessment tool that can establish benchmarks to help focus efforts toward increasing the academic productivity of their respective programs.

Limb salvage is widely practiced as standard of care in most cases of extremity bone sarcoma. Allograft and endoprosthesis reconstructions are the most widely utilized modalities for the reconstruction of large segment defects, however complication rates remain high. Aseptic loosening and infection remain the most common modes of failure. Implant integration, soft-tissue function, and infection prevention are crucial for implant longevity and function. Macro and micro alterations in implant design are reviewed in this manuscript. Tissue engineering principles using nanoparticles, cell-based, and biological augments have been utilized to develop implant coatings that improve osseointegration and decrease infection. Similar techniques have been used to improve the interaction between soft tissues and implants. Tissue engineered constructs (TEC) used in combination with, or in place of, traditional reconstructive techniques may represent the next major advancement in orthopaedic oncology reconstructive science, although preclinical results have yet to achieve durable translation to the bedside.

Author(s): Park, Howard Y; Zoller, Stephen D; Sheppard, William L; Hegde, Vishal; Smith, Ryan A; Borthwell, Rachel M; Clarkson, Samuel J; Hamad, Christopher D; Proal, Joshua D; Bernthal, Nicholas M | Abstract: BackgroundAccording to the American Academy of Orthopaedic Surgeons (AAOS) Standards of Professionalism, the responsible testimony of expert witnesses in orthopaedic surgery malpractice lawsuits is important to the public interest. However, these expert witnesses are recruited and compensated without established standards, and their testimony can potentially sway court opinion, with substantial consequences. The objective of this study was to characterize defense and plaintiff expert orthopaedic surgeon witnesses in orthopaedic surgery malpractice litigation.MethodsUtilizing the WestlawNext legal database, defense and plaintiff expert witnesses involved in orthopaedic surgery malpractice lawsuits from 2013 to 2017 were identified. Each witness's subspecialty, mean years of experience, involvement in academic or private practice, fellowship training, and scholarly impact, as measured by the Hirsch index (h-index), were determined through a query of professional profiles, the Scopus database, and a PubMed search. Statistical comparisons were made for each parameter among defense and plaintiff expert witnesses.ResultsBetween 2013 and 2017, 306 expert medical witnesses for orthopaedic cases were identified; 174 (56.9%) testified on behalf of the plaintiff, and 132 (43.1%) testified on behalf of the defense. Orthopaedic surgeons who identified themselves as general orthopaedists comprised the largest share of expert witnesses on both the plaintiff (n = 61) and defense (n = 25) sides. The plaintiff witnesses averaged 36 years of experience versus 31 years for the defense witnesses (p l 0.001); 26% of the plaintiff witnesses held an academic position versus 43% of the defense witnesses (p = 0.013). Defense witnesses exhibited a higher proportion of fellowship training in comparison to plaintiff expert witnesses (80.5% versus 64.5%, respectively, p = 0.003). The h-index for the plaintiff group was 6.6 versus 9.1 for the defense group (p = 0.04). Two witnesses testified for both the plaintiff and defense sides.ConclusionsDefense expert witnesses held higher rates of academic appointments and exhibited greater scholarly impact than their plaintiff counterparts, with both sides averaging g30 years of experience. These data collectively show that there are differences in characteristics between plaintiff and defense witnesses. Additional study is needed to illuminate the etiology of these differences.

Author(s): Hegde, Vishal; Burke, Zachary DC; Park, Howard Y; Zoller, Stephen D; Johansen, Daniel; Kelley, Benjamin V; Levine, Ben; Motamedi, Kambiz; Federman, Noah C; Seeger, Leanne L; Nelson, Scott D; Bernthal, Nicholas M | Abstract: BACKGROUND:Although there is widespread acceptance of core needle biopsy (CNB) for diagnosing solid tumors, there is reluctance by some clinicians to use CNB for aneurysmal bone cysts (ABCs) as a result of concerns of safety (bleeding, nerve injury, fracture, readmission, or infection) and reliability, particularly to rule out malignant diagnoses like telangiectatic osteosarcoma. This is especially true when CNB tissue is sent from an outside hospital, where the technique used to obtain the tissue may be spurious. QUESTIONS/PURPOSES:(1) Is CNB effective (provided adequate information to indicate appropriate surgical treatment without further open biopsy) as an initial diagnostic test for ABC? (2) Is CNB accurate (pathology consistent with the subsequent definitive surgical pathologic diagnosis) in differentiating between benign lesions such as primary or secondary ABCs and malignant radiolucent lesions such as telangiectatic osteosarcoma? (3) What are the complications of CNB? (4) Is there any difference in the effectiveness or accuracy of CNB performed at outside institutions when compared with a referral center? METHODS:A retrospective study of our musculoskeletal tumor board pathology database (1990-2016) was performed using search criteria "aneurysmal bone cyst" or "telangiectatic osteosarcoma." Only patients undergoing a CNB who proceeded to definitive surgical resection with final pathology were included. Excluding outside CNBs, CNB was performed after presentation at a musculoskeletal tumor board as a result of atypical features on imaging or history concerning for malignancy. Outside CNB tissue was reviewed by our pathologists. If there was sufficient tissue for diagnosis, the patient proceeded to definitive surgery. If not, the patient underwent open biopsy. CNB diagnosis, open biopsy results, and open surgical resection pathology were reviewed. Complications, including bleeding, infection, nerve injury, readmission, or fracture, between the CNB and definitive open surgical procedure (mean 1.6 months) were documented. CNBs were considered "effective" if they yielded pathology considered sufficient to proceed with appropriate definitive surgery without additional open biopsy. CNBs were considered "accurate" if they were effective and yielded a pathologic diagnosis that matched the subsequent definitive surgical pathology. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of obtaining a malignant diagnosis using CNB were also calculated. RESULTS:A total of 81% (59 of 73) of CNBs were effective. Ninety-three percent (55 of 59) of CNBs were classified as accurate. Diagnostic CNBs had a sensitivity and specificity of 89% (eight of nine) and 100% (51 of 51), respectively. The PPV was 1.00 and the NPV was 0.82. There were no complications. With the numbers available, there was no difference in efficacy (90% [37 of 41 versus 14 of 15]; odds ratio, 0.97 [95% confidence interval {CI}, 0.41-2.27], p = 0.94) or accuracy (92% [34 of 37 versus 13 of 14]; odds ratio, 0.87 [95% CI, 0.08-9.16], p = 0.91) between CNBs performed in house and those referred from outside. CONCLUSIONS:These data suggest that CNBs are useful as an initial diagnostic test for ABC and telangiectatic osteosarcoma. Tissue from outside CNBs can be read reliably without repeat biopsy. If confirmed by other institutions, CNB may be considered a reasonable approach to the diagnosis of aggressive, radiolucent lesions of bone. LEVEL OF EVIDENCE:Level III, diagnostic study.

Background and Objective Cemented endoprosthetic reconstruction after resection of primary bone sarcomas has been a standard-of-care option for decades. With increased patient survival, the incidence of failed endoprostheses requiring revision surgery has increased. Revision of cemented endoprotheses by cementing into the existing cement mantle (CiC) is technically demanding. Methods This is a retrospective review of our endoprosthesis database of 512 consecutive cemented endoprosthetic reconstructions performed for oncologic diagnoses between 1980 and 2014. A total of 54 implants (mean patient age 32 years, range 13-81) were revised with a CiC technique. Outcomes evaluated were prosthesis survival, revision surgery categorized according to the Henderson Failure Mode Classification, complications, and functional scores. Results Fifteen-year Kaplan-Meier survival rate was 34% for initial revision and 39% for subsequent revision implants. Mean revised Musculoskeletal Tumor Society (MSTS) Score was 27 at latest follow-up. Infection rate was 2%, 9%, and 13% for primary endoprostheses, initial revisions, and subsequent revisions, respectively. Limb salvage rate was 87%. Conclusions At long-term follow up, endoprostheses revised with the CiC technique showed consistent 15-year survival from initial (34%) to subsequent (39%) revision. Despite a relatively high failure rate, these results are encouraging and demonstrate that this is a conservative, repeatable technique.

BackgroundDespite recent advances, infection remains the most common etiology of arthroplasty failure. Recent work suggests that 25-hydroxyvitamin D (25D) deficiency correlates with the frequency of periprosthetic joint infection (PJI). We endeavored to examine whether 25D3 deficiency leads to increased bacterial burden in vivo in an established mouse model of PJI and, if so, whether this effect can be reversed by preoperative 25D3 supplementation.MethodsMice (lys-EGFP) possessing fluorescent neutrophils were fed a vitamin D3-sufficient (n = 20) or deficient (n = 40) diet for 6 weeks. A group of 25D3-deficient mice (n = 20) were "rescued" with 1 intraperitoneal dose of 25D3 at 3 days before surgery. A stainless steel implant was inserted into the knee joint and the joint space was inoculated with bioluminescent Staphylococcus aureus (1 × 10 colony forming units [CFUs]). In vivo imaging was used to monitor bacterial burden and neutrophil infiltration. Blood was drawn to confirm 25D3 levels 3 days before surgery and on postoperative days (PODs) 0 and 14. Mice were killed at POD 21, and CFUs were quantified after culture. Myeloperoxidase (MPO) and β-N-acetylglucosaminidase (NAG) were assayed to look at neutrophil infiltration and activated tissue macrophage recruitment, respectively.ResultsSerum values confirmed 25D3 deficiency and repletion of the 25D3-rescued group. Bacterial bioluminescence and neutrophil fluorescence were significantly greater (p < 0.05) in the 25D3-deficient group. CFU counts from the joint tissue and implant were also significantly greater in this group (p < 0.05). Rescue treatment significantly decreased bacterial burden and neutrophil infiltration (p < 0.05). Compared with the 25D3-sufficient and 25D3-rescued groups, MPO activity was higher (p < 0.02) and NAG activity was lower (p < 0.03) in the 25D3-deficient group.ConclusionsThis study demonstrated in vivo in a mouse model of PJI that (1) 25D3 deficiency results in increased bacterial burden and neutrophil infiltration, and (2) this effect can be reversed with preoperative repletion of 25D3.Clinical relevanceConsidering that >65% of patients undergoing arthroplasty have insufficient or low levels of total 25D and that 25D levels can be replenished with ease using a U.S. Food and Drug Administration (FDA)-approved, oral 25D3 product, 25D deficiency may be an important modifiable risk factor in humans undergoing joint replacement.

Author(s): Hegde, Vishal; Johansen, Daniel; Park, Howard Y; Zoller, Stephen D; Hamad, Christopher; Bernthal, Nicholas M | Abstract: BackgroundThe Orthopaedic Research and Education Foundation (OREF) is the leading specialty-specific nongovernmental organization providing orthopaedic funding in the United States. As extramural research funding has become increasingly difficult to acquire, one mission of the OREF is to support investigators to generate data needed to secure larger extramural funding from agencies such as the National Institutes of Health (NIH). The objectives of this study were to evaluate the rate of translating OREF faculty-level grants into subsequent NIH funding and to determine if there are identifiable factors that increase the rate of converting an OREF grant into NIH funding.MethodsThis is a retrospective review of OREF grants awarded to full-time faculty orthopaedic surgeons between 1994 and 2014. Grants were analyzed on the basis of award type and were categorized as basic science, clinical, or epidemiological. Sex, individual scholarly productivity, and publication experience were evaluated. All awardees were assessed for subsequent NIH funding using the NIH RePORTER web site.ResultsOne hundred and twenty-six faculty-level OREF grants were awarded to 121 individuals. Twenty-seven OREF grant awardees (22%) received NIH funding at a mean of 6.3 years after OREF funding. Nineteen (46%) of 41 Career Development Grant winners later received NIH funding compared with 10 (12%) of 85 other award winners. OREF grants for basic science projects were awarded more often (58%) and were more than 4 times as likely to result in NIH funding than non-basic science projects (odds ratio, 4.70 [95% confidence interval, 1.66 to 13.33]; p = 0.0036). Faculty who later received NIH funding had higher scholarly productivity and publication experience (p l 0.05).ConclusionsThe OREF grant awardee conversion rate of 22% and, particularly, the 46% for Career Development Grant winners compares favorably with the overall NIH funding success rate (18% in 2014). Faculty-level OREF grants appear to achieve their purpose of identifying and supporting researchers who aim to secure subsequent federal funding.Clinical relevanceThe goal of this study is to examine how successful faculty who have obtained OREF grants have been in securing NIH funding later in their careers. Although subsequent accrual of NIH funding is not the only goal of OREF funding, it can be used as an important benchmark to assess the development of orthopaedic clinician-scientists.

Study design Systematic review and meta-analysis. Objective The goal of this study was to (i) assess the risk of neurological injury after anterior cervical spine surgery (ACSS) with and without intraoperative neuromonitoring (ION) and (ii) evaluate differences in the sensitivity and specificity of ION for ACSS. Summary of background data Although ION is used to detect impending neurological injuries in deformity surgery, it's utility in ACSS remains controversial. Methods A systematic search of multiple medical reference databases was conducted for studies on ION use for ACSS. Studies that included posterior cervical surgery were excluded. Meta-analysis was performed using the random-effects model for heterogeneity. Outcome measure was postoperative neurological injury. Results The search yielded 10 studies totaling 26,357 patients. The weighted risk of neurological injury after ACSS was 0.64% (0.23-1.25). The weighted risk of neurological injury was 0.20% (0.05-0.47) for ACDFs compared with 1.02% (0.10-2.88) for corpectomies. For ACDFs, there was no difference in the risk of neurological injury with or without ION (odds ratio, 0.726; confidence interval, CI, 0.287-1.833; P = 0.498). The pooled sensitivities and specificities of ION for ACSS are 71% (CI: 48%-87%) and 98% (CI: 92%-100%), respectively. Unimodal ION has a higher specificity than multimodal ION [unimodal: 99% (CI: 97%-100%), multimodal: 92% (CI: 81%-96%), P = 0.0218]. There was no statistically significant difference in sensitivities between unimodal and multimodal [68% vs. 88%, respectively, P = 0.949]. Conclusion The risk of neurological injury after ACSS is low although procedures involving a corpectomy may carry a higher risk. For ACDFs, there is no difference in the risk of neurological injury with or without ION use. Unimodal ION has a higher specificity than multimodal ION and may minimize "subclinical" intraoperative alerts in ACSS. Level of evidence 3.

Background Management of spine implant infections (SII) are challenging. Explantation of infected spinal hardware can destabilize the spine, but retention can lead to cord compromise and biofilm formation, complicating management. While vancomycin monotherapy is commonly used, in vitro studies have shown reduced efficacy against biofilm compared to combination therapy with rifampin. Using an established in vivo mouse model of SII, we aim to evaluate whether combination therapy has increased efficacy compared to both vancomycin alone and infected controls. Methods An L-shaped, Kirschner-wire was transfixed into the L4 spinous process of 12-week-old C57BL/6 mice, and inoculated with bioluminescent Staphylococcus aureus. Mice were randomized into a vancomycin group, a combination group with vancomycin plus rifampin, or a control group receiving saline. Treatment began on post-operative day (POD) 7 and continued through POD 14. In vivo imaging was performed to monitor bioluminescence for 35 days. Colony-forming units (CFUs) were cultured on POD 35. Results Bioluminescence peaked around POD 7 for all groups. The combination group had a 10-fold decrease in signal by POD 10. The vancomycin and control groups reached similar levels on POD 17 and 21, respectively. On POD 25 the combination group dropped below baseline, but rebounded to the same level as the other groups, demonstrating a biofilm-associated infection by POD 35. Quantification of CFUs on POD 35 confirmed an ongoing infection in all three groups. Conclusions Although both therapies were initially effective, they were not able to eliminate implant biofilm bacteria, resulting in a rebound infection after antibiotic cessation. This model shows, for the first time, why histologic-based, static assessments of antimicrobials can be misleading, and the importance of longitudinal tracking of infection. Future studies can use this model to test combinations of antibiotic therapies to see if they are more effective in eliminating biofilm prior to human trials.

BACKGROUND CONTEXT Diagnosis and precise localization of spine infections are an elusive pursuit. Despite widespread technical advances, the current standard of magnetic resonance imaging lacks the precision to discern infection versus inflammation due to other causes. Nuclear medicine utilizing the metabolic positron emission tomography (PET) probe18F-fluorodeoxyglucose (18F-FDG) can identify inflammation, but it lacks specificity for bacterial infection. However, adjuncts compatible with PET/CT imaging have the potential to noninvasively increase the specificity for bacteria responsible for spine infections and guide surgeons with regard to the locale and extent of infection. PURPOSE The purpose of this study is to assess the diagnostic potential of utilizing PET/CT and 89-Zirconium (89Zr) labeled bacterial probes in noninvasive, accurate localization of spine implant infections. STUDY DESIGN/SETTING This is a basic science investigation utilizing a mouse model of spine infection. The spine implants are inoculated with bioluminescentStaphylococcus aureusfor longitudinal quantification of bacterial burden, and PET/CT signal intensity is quantified utilizing 18F-FDG and 89Zr-DFO-1D9 mAb intravenous injections. PATIENT SAMPLE Fifteen12-week-oldC57BL/6 wild type mice were utilized. OUTCOME MEASURES In vivobioluminescence and PET/CT signal intensity was quantified utilizing imaging software. Three-dimensional PET/CT images were utilized to localize signal intensities of interest. METHODS In accordance with an established mouse model of spine implant infection, a spinal implant was fixed into the spinous process of the L4 vertebra. Inoculation of the implant and wound bed was performed with bioluminescent S. Aureus. On postoperative day 7, 18F-FDG PET/CT imaging was completed in 11 infected and four sterile control mice. They were also injected intravenously via lateral tail vein with 68.6±1.6 μCi (∼14μgmAb) of89Zr-DFO-1D9 mAb. One week following89Zr-DFO-1D9 injection, mice underwent PET/CT to detect 89Zr-DFO-1D9 mAb signal intensities. RESULTS Bioluminescence imaging revealed signal emitted solely from the surgical bed of infected mice which matched that of historical infected controls – bioluminescence signals remained elevated over the duration of the experiment suggestive of sustained bacterial infection. PET-CT imaging with 18F-FDG probe revealed high signal intensity at the site of the spine implant with lower levels of signal within the gut, bladder, and heart. The 89Zr-DFO-1D9 mAb probe signal in the region of the implant was significantly higher in infected mice compared to sterile controls (2.72e9±1.19e9 versus 6.60E8±3.56E8 total radiant efficiency, respectively;p CONCLUSIONS TheS. aureusspecific89Zr-DFO-1D9 mAb probe was shown by PET/CT imaging to accurately detectinfections in-vivo. This study represents the first in-vivo investigation utilizing PET/CT with intravenous bacterial specific probes which may vastly improve the ability to accurately and noninvasively diagnose and localize spine infections.

Aneurysmal bone cysts (ABCs) are benign bone lesions arising predominantly in the pediatric population that can cause local pain, swelling, and pathologic fracture. Primary lesions, which constitute roughly two thirds of all ABCs, are thought to be neoplastic in nature, with one third of ABCs arising secondary to other tumors. Diagnosis is made with various imaging modalities, which exhibit characteristic features such as "fluid-fluid levels," although biopsy is critical, as telangiectatic osteosarcoma cannot be excluded based on imaging alone. Currently, the standard of care and most widely employed treatment is intralesional curettage. However, tumor recurrence with curettage alone is common and has driven some to propose a multitude of adjuvants with varying efficacy and risk profiles. Historically, therapies such as en bloc resection or radiation therapy were utilized as an alternative to decrease the recurrence rate, but these therapies imposed high morbidity. As a result, modern techniques now seek to simultaneously reduce morbidity and recurrence, the pursuit of which has produced preliminary study into minimally invasive percutaneous treatments and medical management.

PurposeAnterior cruciate ligament (ACL) rupture is increasingly common in adolescents. Time between ACL rupture and surgical reconstruction, surgical wait time, is related to concurrent meniscal tear incidence and possibly tear pattern. This study defines the relationship between meniscal tear characteristics and surgical wait time in adolescents with ACL rupture.MethodsOne-hundred and twenty-one consecutive adolescent (median age 16.1years, range 9-19years) ACL rupture patients undergoing primary ACL reconstruction were studied. All had documented surgical wait time, preoperative and 6-month post-operative outcome (Lysholm and pedi-IKDC) scores, and intraoperative meniscus tear characteristics. Meniscal tear severity was graded according to the Lawrence and Anderson system: non-surgical: grade 1; reparable: grade 2-3; irreparable: grade 4-5. Significant tears were defined as at least grade 2.ResultsAverage age at surgery was 16.1years. 48.7% had surgical wait time greater than 6months. 42.5% of menisci were torn. With surgical wait time 6months, medial tear incidence increased (50 vs 21%, p6months. Public insurance was a risk factor for longer surgical wait time and meniscus tear.

Oxytricha trifallax - an established model organism for studying genome rearrangements, chromosome structure, scrambled genes, RNA-mediated epigenetic inheritance, and other phenomena - has been the subject of a nomenclature controversy for several years. Originally isolated as a sibling species of O. fallax, O. trifallax was reclassified in 1999 as Sterkiella histriomuscorum, a previously identified species, based on morphological similarity. The proper identification of O. trifallax is crucial to resolve in order to prevent confusion in both the comparative genomics and the general scientific communities. We analyzed nine conserved nuclear gene sequences between the two given species and several related ciliates. Phylogenetic analyses suggest that O. trifallax and a bona fide S. histriomuscorum have accumulated significant evolutionary divergence from each other relative to other ciliates such that they should be unequivocally classified as separate species. We also describe the original isolation of O. trifallax, including its comparison to O. fallax, and we provide criteria to identify future isolates of O. trifallax.

Alteration in platelet aggregation has been shown to promote bleeding and affect outcome after intracerebral hemorrhage (ICH).We investigated the influence of genetic variants of platelet aggregation, and their effects on admission ICH volume and clinical outcome.Our prospective study analyzed selected candidate single-nucleotide polymorphisms (SNPs) previously associated with platelet aggregation phenotype in previous genome-wide association studies, with regards to outcome and ICH volume. Patients were assessed at the Columbia University Medical Center Neuro-Intensive Care Unit. Exclusion criteria included age18 years, ICH following trauma, hemorrhagic transformation, or tumor, no consent for genetic analysis, or incomplete data. Radiological variables (location and volume of acute ICH, presence of intraventricular extension, midline shift, and hydrocephalus) and clinical variables (mortality and modified Rankin score at discharge) were prospectively recorded.One hundred and twenty-two patients with spontaneous ICH between February 2009 and May 2011 diagnosed via clinical assessment and admission computed tomography scan were included. The median admission Glasgow coma scale score (GCS) was 11·5. Univariate predictors of mortality at discharge included systolic blood pressure, presence of intraventricular hemorrhage, anticoagulant use, and GCS, the only independent predictor of discharge mortality (P0·001). Age, intraventricular hemorrhage, and GCS were associated with poor functional outcome; age (P = 0·001) and GCS (P0·001) were significant in the multivariate model. Admission GCS (P0·01), antiplatelet use, and rs342286 (PIK3CG; P = 0·04; R(2) = 0·247) had univariate associations with hematoma volume.We identified SNP rs342286 as an independent predictor of admission hematoma volume. Our findings suggest that PIK3CG function, which is previously linked to this SNP and affects platelet aggregation, impacts the severity of the intraparenchymal bleed.

BACKGROUND CONTEXT Surgical debridement of spine infections consists of excising tissue at the surgeon's discretion. Surgeon's rely on visual cues such as abnormal tissue coloration and consistency to determine the extent of debridement. However, complete and accurate debridement is difficult to assess given the lack of objective data with regard to location and extent of residual infection. PURPOSE The purpose of this study is to apply two emerging technologies: (1) novelStaphylococcus aureustargeting fluorescently labeled probes and (2) “OR ready” real-time fluorescent imaging system, in a proof of principle study evaluating the feasibility of image-guided debridement surgery. STUDY DESIGN/SETTING This is a basic science investigation utilizing a mouse model of spinal implant infection. BioluminescentStaphylococcus aureusis used for longitudinal quantification of bacterial burden. Once infections were established, an open-air, “OR ready” fluorescent imaging system was utilized for image guided surgery. PATIENT SAMPLE Thirty-six 12-week-oldC57BL/6 wild type mice were utilized, 10 for each experimental group. OUTCOME MEASURES Utilizing an established mouse model of spinal implant infection,in vivobioluminescence and fluorescence imaging was performed to quantify emitted signals. A recently developed open-air, fluorescence input image-guided surgery system was utilized to for debridement surgery and to evaluate residual bacterial burden on debrided tissue. METHODS Three groups of mice were subjected to a previously established spine implant infection model: (1) five mice with implants inoculated withS. aureusand one sterile control mouse 60 days prior to image-guided debridement, (2) 10 inoculated and five sterile mice 30 days prior, (3) 10 inoculated and five sterile control mice 7 days prior. A total of 24 hours prior to debridement surgery, aS. aureusImmunodominant Staphylococcal Antigen A (IsaA) antibody fluorescent probe was administered via tail vein injection. Fluorescent imaging was completed to confirm co-localization of the probe to bioluminescent bacteria. Mice were then subjected to a fluorescence image-guided surgery system for debridement. RESULTS Two of five mice from the 60-day group, 8/10 of the 30-day group, and 10/10 of the 7-day group established an infection confirmed by bioluminescence imaging. Subsequent fluorescence imaging following IsaA-antibody probe injection revealed co-localization of fluorescent probe to bioluminescent bacteria with high fidelity. Radical debridement of fluorescent material under the image-guided surgery system was completed which revealed fluorescently labeled tissue with continued light emissionex-vivo.No fluorescence remained in mice status post debridement, indicating successful infection excision. CONCLUSIONS The novel,S. aureusspecific fluorescent probe successfully labelled bacteria in chronic and acute spine implant infections.Furthermore, this probe was successfully applied to the image-guided surgery system.This technology has the potential to shift the paradigm in excision surgery with applications in infection and negative margin tumor surgery.

Laminectomy with fusion (LF) and laminoplasty are two posterior-based surgical approaches for the surgical treatment of cervical spondylotic myelopathy (CSM). The decompressive effect of these approaches is thought to be primarily related to the dorsal drift of the spinal cord away from ventral compressive structures. A lesser known mechanism of spinal cord decompression following cervical LF is regression of the ventral disc osteophyte complexes which is postulated to result from the alteration of motion across the fused motion segment. The goal of this study was to determine whether regression of the ventral disc-osteophyte complexes occur following laminoplasty and compare the magnitude of this occurrence to cervical laminectomy and fusion.Seventy patients with CSM who underwent pre- and postoperative magnetic resonance imaging (MRI) and were treated with either laminoplasty or LF. The size of the disc-osteophyte complex at all operative levels were measured on pre- and postoperative MRI using digital calipers.The laminoplasty group consisted of 25 patients with an average age of 54.9 and a mean of 3.24 surgical levels while the LF group consisted of 45 patients with an average age of 65.4 and a mean of 3.44 surgical levels (age, p0.0001; levels, p= 0.46). The average time interval between pre- and post-operative MRI was 16.2 and 15.6 months in the laminoplasty and LF groups, respectively (p = 0.91). The average time interval between surgery and post-operative MRI was 10.1 and 10.7 months in the laminoplasty and LF groups, respectively (p = 0.86). When comparing pre- and post-operative MRI, there was a 9.59% decrease in disc-osteophyte complex size from 3.84mm ± 0.74 to 3.47mm ± 0.86 in the laminoplasty group compared to a 35.4% decrease in disc-osteophyte complex size from 4.60mm ± 1.06 to 2.98mm ± 1.33 in LF group (laminoplasty, p0.0001; LF, p = 0.0067). Using logistic regression analysis, LF, increased time interval between surgery and post-operative MRI, high cobb angle, and straight sagittal alignment were all independently associated with increased disc-osteophyte complex regression (p0.05). No differences in functional outcomes (as defined by mJOA scores) was found between the two surgical techniques.In patients with CSM that had a posterior surgical approach, LF is associated with a larger interval regression in disc-osteophyte complex size compared to laminoplasty. This is likely related to the loss of motion of the cervical spine after surgery as governed by Wolff's law and the Heuter-Volkmann's principle. Although the decompressive effect of LF and laminoplasty is primarily related to the dorsal drift of the spinal cord away from ventral compressive structures, disc-osteophyte complex regression likely provides another mechanism of spinal cord decompression.

Background: Proximal humerus fractures are one of the most common fractures among elderly patients. We performed a systematic review to detail the demographics, outcomes, and complications of patients who undergo reverse shoulder arthroplasty for complex proximal humerus fractures. Methods: A systematic review of the literature was performed. Two reviewers assessed and confirmed the methodical quality of each study. Studies that met our criteria were assessed for pertinent data, and when available, similar outcomes were combined to generate frequency-weighted means. Results: Nine studies met the inclusion and exclusion criteria for this review. The frequency weighted mean age was 77.5 years and the mean follow up was 43.2 months. Females comprised 90.4% of the patient population. Four-part fractures were most commonly encountered. The frequency weighted mean constant’s score was 55.9. Frequency weighted mean active forward flexion, abduction, and external rotation at neutral were 122 � ,9 7 � ,a nd 18 � , respectively. Tuberosity repair was associated with significantly higher external rotation compared to no repair (24 � vs 15 � ; P ¼.0003). The most common complication was scapular notching (32%) while the impact of this finding remains unknown. Conclusion: Pooled data and frequency weighted mean outcomes showed that RSA patients tend to be elderly women and still have postoperative dysfunction despite well-controlled pain. Repair of the greater tuberosity allows greater range of motion in patients. Level of evidence: Level IV, Systematic Review. 2014 Journal of Shoulder and Elbow Surgery Board of Trustees.

Traumatic brain injury (TBI) is the current leading cause of death in children over 1 year of age. Adequate management and care of pediatric patients is critical to ensure the best functional outcome in this population. In their controversial trial, Cooper et al. concluded that decompressive craniectomy following TBI did not improve clinical outcome of the analyzed adult population. While the study did not target pediatric populations, the results do raise important and timely clinical questions regarding the effectiveness of decompressive surgery in pediatric patients. There is still a paucity of evidence regarding the effectiveness of this therapy in a pediatric population, and there is an especially noticeable knowledge gap surrounding age-stratified interventions in pediatric trauma. The purposes of this review are to first explore the anatomical variations between pediatric and adult populations in the setting of TBI. Second, the authors assess how these differences between adult and pediatric populations could translate into differences in the impact of decompressive surgery following TBI.