Evaluating the Ability of Brachial Plexus-Injured Patients to Control an Externally Powered (Myoelectric) Hand Prosthesis.

BACKGROUND: Restoration of hand function after traumatic brachial plexus injury (BPI) remains a formidable challenge. Traditional methods such as nerve or free muscle transfers yield suboptimal results. Advancements in myoelectric prostheses, characterized by novel signal acquisition and improved material technology, show promise in restoring functional grasp. This study evaluated the ability of adults with a BPI injury to control an externally powered prosthetic hand using nonintuitive signals, simulating the restoration of grasp with a myoelectric prosthesis. It also assessed the effectiveness of a comprehensive multidisciplinary evaluation in guiding treatment decisions. METHODS: A multidisciplinary brachial plexus team assessed adults with compromised hand function due to BPI. The feasibility of amputation coupled with fitting of a myoelectric prosthesis for grasp reconstruction was evaluated. Participants' ability to control a virtual or model prosthetic hand using surface electromyography (EMG) as well as with contralateral shoulder motion-activated linear transducer signals was tested. The patient's input and injury type, along with the information from the prosthetic evaluation, were used to determine the reconstructive plan. The study also reviewed the number of participants opting for amputation and a myoelectric prosthetic hand for grasp restoration, and a follow-up survey was conducted to assess the impact of the initial evaluation on decision-making. RESULTS: Of 58 subjects evaluated, 47 (81%) had pan-plexus BPI and 42 (72%) received their initial assessment within 1 year post-injury. Forty-seven patients (81%) could control the virtual or model prosthetic hand using nonintuitive surface EMG signals, and all 58 could control it with contralateral uniscapular motion via a linear transducer and harness. Thirty patients (52%) chose and pursued amputation, and 20 (34%) actively used a myoelectric prosthesis for grasp. The initial evaluation was informative and beneficial for the majority of the patients, especially in demonstrating the functionality of the myoelectric prosthesis. CONCLUSIONS: The study indicates that adults with traumatic BPI can effectively operate a virtual or model myoelectric prosthesis using nonintuitive control signals. The simulation and multidisciplinary evaluation influenced informed treatment choices, with a high percentage of patients continuing to use the myoelectric prostheses post-amputation, highlighting its long-term acceptance and viability. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The role of vascularized bone grafting for scaphoid nonunions in adolescents.

A total of 26 adolescent patients were treated for scaphoid nonunion with a vascularized bone graft from either the medial femoral condyle or dorsal distal radius. There was an 85% union incidence, improved carpal alignment and a low incidence of complications.

Injury and Biological Factors Impact Shoulder Function following Autogenous Grafting of Spinal Nerves for Pan-Brachial Plexus Reconstruction.

BACKGROUND: Shoulder function following spinal nerve grafting in pan-brachial plexus injuries(Pan-BPI) is not well described. The purpose of this study was twofold: 1)to evaluate shoulder abduction(ABD) and external rotation(ER) after grafting of viable spinal nerves to the suprascapular nerve(SSN), axillary nerve(AxN), or posterior division of the upper trunk(PDUT); and 2)to determine patient characteristics, injury severity/characteristics, and nerve graft factors that influenced outcomes. METHODS: 362 Pan-BPI reconstruction patients from a single institution were reviewed for those who underwent spinal nerve grafting for shoulder reanimation between 2001 and 2018. Patient demographics, injury severity scores(ISS), graft characteristics, strength, range of motion for shoulder ABD and ER, and patient-reported outcomes were recorded. Patients were divided into three groups based on the recovery of shoulder function: no return, ABD only, and ABD and ER. RESULTS: 110 patients underwent spinal nerve grafting, with 41 meeting inclusion criteria. 17(41.5%) had no return of shoulder function, 14(34.1%) had ABD alone, and 10(24.4%) had ABD and ER. Patients with recovery of both ABD and ER were significantly younger(18.6±5.56), had lower BMI(22.4±4.0), and lower ISS(10.5±6.24, p=0.003). Multivariable analysis found that with increasing age(OR:0.786, 95%CI:0.576,0.941) and ISS(OR:0.820, 95%CI:0.606-0.979), odds for return of ABD and ER significantly decreased. CONCLUSIONS: In Pan-BPI, 24.4% of patients demonstrated return of both ABD and ER following spinal nerve grafting to SSN and either AxN or PDUT. Age, BMI, and ISS were associated with poorer recovery of shoulder function. Careful patient selection and consideration of age, BMI, and ISS may improve outcomes of spinal nerve grafting for shoulder reanimation. LEVEL OF EVIDENCE: III.

Validation of the Root Analysis Score for C5 Viability in Patients With Pan-Brachial Plexus Injury.

PURPOSE: Pan-brachial plexus injury patients present a reconstructive challenge. The root analysis score, developed from parsimonious multivariable modeling of 311 pan-brachial plexus injury patients, determines the probability of having a viable C5 nerve based on four categories: positive C5 Tinel test, intact C5 nerve on computed tomography myelogram, lack of hemidiaphragmatic elevation, and absence of midcervical paraspinal fibrillations. METHODS: Root analysis scores were calculated for a separate cohort of patients with pan-brachial plexus injuries. Scores were validated by the presence or absence of a graftable C5 root, based on supraclavicular exploration and intraoperative electrophysiologic testing. Receiver operating characteristic curve, accuracy, and concordance statistic of the scores were calculated. Patients were divided into three root analysis score cohorts: less than 50 (low), 50-75 (average), and 75-100 points (high) based on dividing the score into quartiles and combining the lowest two. The probability, sensitivity, and specificity of each cohort having an available C5 nerve were based on the intraoperative assessment. RESULTS: Eighty patients (mean age, 33.1 years; 15 women and 65 men) were included. Thirty-one patients (39%) had a viable C5 nerve. The root analysis calculator had an overall accuracy of 82.5%, a receiver operating characteristic of 0.87, and a concordance statistic of 0.87, demonstrating high overall predictive value; 6.5% of patients with a score of less than 50 (94% sensitivity and 43% specificity), 16.1% of patients with a score of 50-75 (94% sensitivity and 67% specificity), and 77.4% of patients with a score of 75-100 (77% sensitivity and 90% specificity) had a graftable C5 nerve. CONCLUSIONS: The root analysis score demonstrated high accuracy and predictive power for a viable C5 nerve. In patients with a score of less than 50, the necessity of supraclavicular root exploration should balance patient factors, presentation timing, and concomitant injuries. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnosis II.

The 2-by-2 Inch "Key Window" in the Upper Extremity: An Anatomical Appraisal of the Accessibility and Proximity of the Major Nerves and Vessels.

BACKGROUND: The brachial plexus is a network of nerves located between the neck and axilla, which receives input from C5-T1. Distally, the nerves and blood vessels that supply the arm and forearm form a medial neurovascular bundle. The purpose of this study was to illustrate that a peripheral nerve dissection via a 2 × 2 inch window would allow for identification and isolation of the major nerves and blood vessels that supply the arm and forearm. METHODS: A right side formalin-fixed latex-injected cadaveric arm was transected at the proximal part of the axillary fold and included the scapular attachments. Step-by-step anatomical dissection was carried out and documented with three-dimensional digital imaging. RESULTS: A 2 × 2 inch window centered 2 inches distal to the axillary fold on the medial surface of the arm enabled access to the major neurovascular structures of the arm and forearm: the median nerve, ulnar nerve, medial antebrachial cutaneous nerve, radial nerve and triceps motor branches, musculocutaneous nerve and its biceps and brachialis branches and lateral antebrachial cutaneous nerve, basilic vein and brachial artery and vein, and profunda brachii artery. CONCLUSIONS: Our study demonstrates that the majority of the neurovascular supply in the arm and forearm can be accessed through a 2 × 2 inch area in the medial arm. Although this "key window" may not be entirely utilized in the operative setting, our comprehensive didactic description of peripheral nerve dissection in the cadaver laboratory can help in safer identification of complex anatomy encountered during surgical procedures.

The failed adult traumatic brachial plexus reconstruction.

Traumatic adult brachial plexus injuries typically cause immediate loss of upper limb function. Timely multidisciplinary treatment in specialized centres often results in a useful helper arm. Both the patient and the surgical team can benefit from an open discussion to set realistic expectations. Surgical reconstruction is customized for each patient, considering their injury factors and functional objectives. Optimizing pain control, adherence to procedure indications and using meticulous surgical techniques help minimize the risk of failing to meet the patient's goals. The need for potential alternative treatment(s) if the desired result is not achieved should be detailed before the initial reconstruction. This review discusses late treatment options, including tendon transfers, joint fusions, free functioning muscle transfers and prosthetics, for managing the failed primary reconstruction of the traumatic adult brachial plexus.

Global trends and outcomes of nerve transfers for treatment of adult brachial plexus injuries.

The presentation, management and outcomes of brachial plexus injuries are likely to be subject to regional differences across the globe. A comprehensive literature search was performed to identify relevant articles related to spinal accessory to suprascapular, intercostal to musculocutaneous, and ulnar and/or median nerve fascicle to biceps and/or brachialis motor branch nerve transfers for treatment of brachial plexus injuries. A total of 6007 individual brachial plexus injuries were described with a mean follow-up of 38 months. The specific indication for accessory to suprascapular and intercostal to musculocutaneous transfers were considerably different among regions (e.g. upper plexus vs. pan-plexal), while uniform for fascicular transfer for elbow flexion (e.g. upper plexus +/- C7). Similarly, functional recovery was highly variable for accessory to suprascapular and intercostal to musculocutaneous transfers, while British Medical Research Council grade ≥3 strength after fascicular transfer for elbow flexion was frequently obtained. Overall, differences in outcomes seem to be inherent to the specific transfer being utilized.Level of evidence: III.

Complications of operatively treated distal radial fractures.

Distal radial fractures represent the most common fractures of the upper extremity. Operative treatment is performed for approximately one-third of distal radial fractures in the adult population. Complications following operative treatment of distal radial fractures vary depending on the treatment modality and can be stratified into preoperative and postoperative complications. Complications can occur in the near, intermediate and long term. The most common complications seen are tendon irritation and rupture, chronic regional pain syndrome (CRPS), carpal tunnel syndrome, ulnar or radial neuropathy, compartment syndrome, malunion, inadequate fixation or loss of fixation, symptomatic hardware, post-traumatic arthritis, stiffness and infection. Careful planning, treatment and patient selection can help to mitigate these complications.Level of evidence: V.

The Effect of Local Purified Exosome Product, Stem Cells, and Tacrolimus on Neurite Extension.

PURPOSE: The combination of cellular and noncellular treatments has been postulated to improve nerve regeneration through a processed nerve allograft. This study aimed to evaluate the isolated effect of treatment with purified exosome product (PEP), mesenchymal stem cells (MSCs), and tacrolimus (FK506) alone and in combination when applied in decellularized allografts. METHODS: A three-dimensional in vitro-compartmented cell culture system was used to evaluate the length of regenerating neurites from the neonatal dorsal root ganglion into the adjacent peripheral nerve graft. Decellularized nerve allografts were treated with undifferentiated MSCs, 5% PEP, 100 ng/mL FK506, PEP and FK506 combined, or MSCs and FK506 combined (N = 9/group) and compared with untreated nerve autografts (positive control) and nerve allografts (negative control). Neurite extension was measured to quantify nerve regeneration after 48 hours, and stem cell viability was evaluated. RESULTS: Stem cell viability was confirmed in all MSC-treated nerve grafts. Treatments with PEP, PEP + FK506, and MSCs + FK506 combined were found to be superior to untreated allografts and not significantly different from autografts. Combined PEP and FK506 treatment resulted in the greatest neurite extension. Treatment with FK506 and MSCs was significantly superior to MSC alone. The combined treatment groups were not found to be statistically different. CONCLUSIONS: Although all treatments improved neurite outgrowth, treatments with PEP, PEP + FK506, and MSCs + FK506 combined had superior neurite growth compared with untreated allografts and were not found to be significantly different from autografts, the current gold standard. CLINICAL RELEVANCE: Purified exosome product, a cell-free exosome product, is a promising adjunct to enhance nerve allograft regeneration, with possible future avenues for clinical translation.

Investigation Into the Effects of Intra-Articular Steroid on Post-Traumatic Osteoarthritis in Distal Radius Fractures: A Randomized Controlled Pilot Study.

PURPOSE: The aim of this prospective, randomized, controlled, double-blinded pilot study was to determine the rates of post-traumatic osteoarthritis and assess joint space width in the presence or absence of a single intra-articular injection of corticosteroid after an acute, intra-articular distal radius fracture (DRF). METHODS: Forty patients received a single, intra-articular, radiocarpal joint injection of 4 mg of dexamethasone (DEX) (n = 19) or normal saline placebo (n = 21) within 2 weeks of a surgically or nonsurgically treated intra-articular DRF. The primary outcome measure was minimum radiocarpal joint space width (mJSW) on noncontrast computed tomography scans at 2 years postinjection. Secondary outcomes were obtained at 3 months, 6 months, 1 year, and 2 years postinjection and included Disabilities of the Arm, Shoulder, and Hand; Michigan Hand Questionnaire; Patient-Rated Wrist Evaluation; wrist range of motion; and grip strength. RESULTS: At 2-year follow-up, there was no difference in mean mJSW between the DEX group (2.2 mm; standard deviation, 0.6; range, 1.4-3.2) and the placebo group (2.3 mm; standard deviation, 0.7; range, 0.9-3.9). Further, there were no differences in any secondary outcome measures at any postinjection follow-up interval. CONCLUSIONS: Radiocarpal joint injection of corticosteroid within 2 weeks of an intra-articular DRF does not appear to affect the development of post-traumatic osteoarthritis within 2 years follow-up in a small pilot cohort. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II.

A three-dimensional computed tomography study of the palmar ulnar corner fragment in distal radial fractures.

Fixing palmar ulnar corner fragments of distal radial fractures can be challenging. We described the palmar ulnar corner fragment morphology in a retrospective cohort study of 40 patients who underwent preoperative wrist computed tomography scans. Palmar ulnar corner fractures were categorized based on articular cross-sectional area, sagittal angulation relative to the radius long axis, palmar cortical length, radioulnar width and associated palmar radiocarpal subluxation. Three types emerged: type 1 fragments involved 37% (SD 10) of the radiocarpal articular surface and were extended in the sagittal plane; type 2 fragments involved 28% (SD 10) of the articular surface and had a long palmar cortex, of which 57% had palmar carpal subluxation; and type 3 fragments involved 13% (SD 2) of the articular surface, had a short palmar cortex and all had palmar carpal subluxation. Understanding palmar ulnar corner fragment morphology may guide optimal reduction and fixation strategy and prevent palmar radiocarpal subluxation, especially in type 3 fractures.Level of evidence IV.

The Role of Exosomes in Upper-Extremity Tissue Regeneration.

Exosomes are cell-free membrane vesicles secreted by a wide variety of cells as secretomes into the extracellular matrix. Alongside facilitating intercellular communication, exosomes carry various bioactive molecules consisting of nucleic acids, proteins, and lipids. Exosome applications have increased in popularity by overcoming the disadvantages of mesenchymal stem cell therapies. Despite this, a better understanding of the underlying mechanisms of action of exosomes is necessary prior to clinical application in upper-extremity tissue regeneration. The purpose of this review is to introduce the concept of exosomes and their possible applications in upper-extremity tissue regeneration, detail the shortcomings of current exosome research, and explore their potential clinical application in the upper extremity.

Osteolysis After Augmented Scapholunate Ligament Reconstruction: A Report of 3 Cases.

CASE: Augmented scapholunate ligament reconstruction using polyether ether ketone anchors and ultra-high molecular weight polyethylene synthetic tape has the theoretical advantage of improved stability, avoidance of K-wire fixation, and the potential for earlier mobilization. We present 3 cases of scaphoid and lunate osteolysis/fragmentation, operative and histologic findings at reoperation, and the sequelae of this technique. CONCLUSION: If planning to use suture anchors and synthetic tapes in small carpal bones, we recommend advising patients about the risk of osteolysis and monitoring closely patients who complain of pain with motion after surgery.

Upper extremity asymmetry due to nerve injuries or central neurologic conditions: a scoping review.

BACKGROUND: Peripheral nerve injuries and central neurologic conditions can result in extensive disabilities. In cases with unilateral impairment, assessing the asymmetry between the upper extremity has been used to assess outcomes of treatment and severity of injury. A wide variety of validated and novel tests and sensors have been utilized to determine the upper extremity asymmetry. The purpose of this article is to review the literature and define the current state of the art for describing upper extremity asymmetry in patients with peripheral nerve injuries or central neurologic conditions. METHOD: An electronic literature search of PubMed, Scopus, Web of Science, OVID was performed for publications between 2000 to 2022. Eligibility criteria were subjects with neurological conditions/injuries who were analyzed for dissimilarities in use between the upper extremities. Data related to study population, target condition/injury, types of tests performed, sensors used, real-world data collection, outcome measures of interest, and results of the study were extracted. Sackett's Level of Evidence was used to judge the quality of the articles. RESULTS: Of the 7281 unique articles, 112 articles met the inclusion criteria for the review. Eight target conditions/injuries were identified (Brachial Plexus Injury, Cerebral Palsy, Multiple Sclerosis, Parkinson's Disease, Peripheral Nerve Injury, Spinal Cord Injury, Schizophrenia, and stroke). The tests performed were classified into thirteen categories based on the nature of the test and data collected. The general results related to upper extremity asymmetry were listed for all the reviewed articles. Stroke was the most studied condition, followed by cerebral palsy, with kinematics and strength measurement tests being the most frequently used tests. Studies with a level of evidence level II and III increased between 2000 and 2021. The use of real-world evidence-based data, and objective data collection tests also increased in the same period. CONCLUSION: Adequately powered randomized controlled trials should be used to study upper extremity asymmetry. Neurological conditions other than stroke should be studied further. Upper extremity asymmetry should be measured using objective outcome measures like motion tracking and activity monitoring in the patient's daily living environment.

Functional outcomes of nerve allografts augmented with mesenchymal stem cells and surgical angiogenesis in a rat sciatic nerve defect model.

BACKGROUND: Motor function recovery following acellular nerve allograft (ANA) repair remains inferior to autologous nerve reconstruction. We investigated the functional recovery of ANAs after combined mesenchymal stem cell (MSC) delivery and surgical angiogenesis in a rat sciatic nerve defect model. METHODS: In 100 Lewis rats, unilateral sciatic nerve defects were reconstructed with (I) autografts, (II) ANAs, (III) ANAs wrapped with a superficial inferior epigastric artery fascial (SIEF) flap, combined with either (IV) undifferentiated MSCs or (V) Schwann cell-like differentiated MSCs. The tibialis anterior muscle area was evaluated during the survival period using ultrasonography. Functional recovery, histomorphometry, and immunofluorescence were assessed at 12 and 16 weeks. RESULTS: At 12 weeks, the addition of surgical angiogenesis and MSCs improved ankle contractures. The SIEF flap also significantly improved compound muscle action potential (CMAP) outcomes compared with ANAs. Autografts outperformed all groups in muscle force and weight. At 16 weeks, ankle contractures of ANAs remained inferior to autografts and SIEF, whereas the CMAP amplitude was comparable between groups. The muscle force of autografts remained superior to all other groups, and the muscle weight of ANAs remained inferior to autografts. No differences were found in histomorphometry outcomes between SIEF groups and ANAs. Vascularity, determined by CD34 staining, was significantly higher in SIEF groups compared with ANAs. CONCLUSIONS: The combination of surgical angiogenesis and MSCs did not result in a synergistic improvement in functional outcomes. In a short nerve gap model, the adipofascial flap may provide sufficient MSCs to ANAs without additional ex vivo MSC seeding.

The Effect of 3rd Carpometacarpal Arthrodesis in the Outcomes of Total Wrist Fusion Using Modern Plate Technology.

Background The inclusion of the third carpometacarpal (CMC) joint in the fusion mass in total wrist fusion (TWF) remains controversial. Our goal was to evaluate the clinical outcomes and effects of third CMC joint arthrodesis compared with bridging the CMC joint during TWF. A retrospective chart review was performed. Outcomes assessed included hardware loosening, hardware failure, symptomatic hardware necessitating removal, and need for revision arthrodesis. Case Description/Literature Review We found that concomitant third CMC joint arthrodesis was associated with a significantly reduced rate of radiocarpal and midcarpal joint nonunion, hardware loosening, and symptomatic hardware removal when compared to bridging of the CMC joint. There was no significant difference in hardware failure rates or the need for revision arthrodesis. Clinical Relevance When using a contoured dorsal spanning plate, concomitant CMC joint arthrodesis should be considered during TWF to mitigate against hardware loosening and symptomatic hardware. Level of Evidence Level IV.

Clinical trials in Charcot-Marie-Tooth disorders: a retrospective and preclinical assessment.

Objective: This study aimed to evaluate the progression of clinical and preclinical trials in Charcot-Marie-Tooth (CMT) disorders. Background: CMT has historically been managed symptomatically and with genetic counseling. The evolution of molecular and pathologic understanding holds a therapeutic promise in gene-targeted therapies. Methods: ClinicalTrials.gov from December 1999 to June 2022 was data extracted for CMT with preclinical animal gene therapy trials also reviewed by PubMed search. Results: The number of active trials was 1 in 1999 and 286 in 2022. Academic settings accounted for 91% and pharmaceutical companies 9%. Of the pharmaceutical and academic trials, 38% and 28%, respectively, were controlled, randomized, and double-blinded. Thirty-two countries participated: the United States accounted for 26% (75/286). In total, 86% of the trials were classified as therapeutic: 50% procedural (21% wrist/elbow surgery; 22% shock wave and hydrodissection therapy), 23% investigational drugs, 15% devices, and 11% physical therapy. Sixty-seven therapeutic trials (49%) were designated phases 1-2 and 51% phases 3-4. The remaining 14% represent non-therapeutic trials: diagnostic testing (3%), functional outcomes (4%), natural history (4%), and standard of care (3%). One-hundred and three (36%) resulted in publications. Phase I human pharmaceutical trials are focusing on the safety of small molecule therapies (n = 8) and AAV and non-viral gene therapy (n = 3). Preclinical animal gene therapy studies include 11 different CMT forms including viral, CRISPR-Cas9, and nanoparticle delivery. Conclusion: Current CMT trials are exploring procedural and molecular therapeutic options with substantial participation of the pharmaceutical industry worldwide. Emerging drug therapies directed at molecular pathogenesis are being advanced in human clinical trials; however, the majority remain within animal investigations.

Pediatric Upper Extremity Trauma Secondary to All-terrain Vehicle Use.

All-terrain vehicles (ATVs) have become popular with respect to recreational activities. Multiple orthopaedic and pediatric organizations currently recommend limiting use of ATVs to older age groups of children with supervision. These recommendations have not generally been adhered to, resulting in a disproportionate number of pediatric orthopaedic trauma, specifically of the upper extremities. A retrospective review of patients 18-years-old and younger who presented to a single, Level I Trauma Center with ATV-related upper extremity trauma between 1996 and 2006 was undertaken to determine the impact of ATV use on the upper extremities of children. A total of 65 patients were identified with an average age of 12.3. Only 29.2% wore helmets and 73.8% were drivers. The hand and elbow were the most common injury sites in patients under age 12, elbow for those between ages 12 and 16, and wrist for those over age 16 (p = 0.031). Fractures/Dislocations were the most common injury in all age groups (p = 0.0077). The most performed surgical procedure was open reduction internal fixation of fractures, and patients required an average of 4.8 total operations. Patients who had non-isolated upper extremity injuries were associated with longer hospital stays (p = 0.011) but not ICU stays (p = 0.10). In order to reduce pediatric upper extremity injuries from ATVs, restrictions must be more stringent and safety education made a priority. (Journal of Surgical Orthopaedic Advances 32(2):088-091, 2023).