Targeted muscle reinnervation and regenerative peripheral nerve interfaces for pain prophylaxis and treatment: A systematic review.

OBJECTIVE: Nerve pain frequently develops following amputations and peripheral nerve injuries. Two innovative surgical techniques, targeted muscle reinnervation (TMR) and regenerative peripheral nerve interfaces (RPNI), are rapidly gaining popularity as alternatives to traditional nerve management, but their effectiveness is unclear. LITERATURE SURVEY: A review of literature pertaining to TMR and RPNI pain results was conducted. PubMed and MEDLINE electronic databases were queried. METHODOLOGY: Studies were included if pain outcomes were assessed after TMR or RPNI in the upper or lower extremity, both for prophylaxis performed at the time of amputation and for treatment of postamputation pain. Data were extracted for evaluation. SYNTHESIS: Seventeen studies were included, with 14 evaluating TMR (366 patients) and three evaluating RPNI (75 patients). Of these, one study was a randomized controlled trial. Nine studies had a mean follow-up time of at least 1 year (range 4-27.6 months). For pain treatment, TMR and RPNI improved neuroma pain in 75%-100% of patients and phantom limb pain in 45%-80% of patients, averaging a 2.4-6.2-point reduction in pain scores on the numeric rating scale postoperatively. When TMR or RPNI was performed prophylactically, many patients reported no neuroma pain (48%-100%) or phantom limb pain (45%-87%) at time of follow-up. Six TMR studies reported Patient-Reported Outcomes Measurement Information System (PROMIS) scores assessing pain intensity, behavior, and interference, which consistently showed a benefit for all measures. Complication rates ranged from 13% to 31%, most frequently delayed wound healing. CONCLUSIONS: Both TMR and RPNI may be beneficial for preventing and treating pain originating from peripheral nerve dysfunction compared to traditional techniques. Randomized trials with longer term follow-up are needed to directly compare the effectiveness of TMR and RPNI with traditional nerve management techniques.

Force-amplifying implant to improve key pinch strength in tendon transfer surgery: Cadaver model proof-of-concept.

The brachioradialis (BR) to flexor pollicis longus (FPL) tendon transfer surgery is a common procedure used to restore key pinch grip for incomplete spinal cord injury patients. However, the procedure only restores 22% of the physiological grip strength, which is important for successfully grasping objects and minimizing fatigue. The purpose of this study was to evaluate the efficacy of using a novel force-amplifying pulley implant to modify the standard BR to FPL tendon transfer surgery to improve key pinch grip strength in a human cadaver forearm model. A total of eight cadaveric specimens were mounted onto a custom testbed where a torque-controlled motor actuated the BR tendon to produce key pinch grip. In each cadaver, two experimental groups were examined: a standard and an implant-modified BR to FPL tendon transfer surgery. A force sensor mounted to the thumb recorded isometric key pinch grip forces over a range of input BR forces (2 N-25 N) applied in a ramp-and-hold protocol. Across the range of input BR forces, the average improvement in key pinch grip strength in the implant-modified surgery compared to the standard surgery was 58 ± 7.1% (ranging from 41% to 64% improvement). Throughout the experiments, we observed that the implant did not hinder the movement of the BR or FPL tendons. These results suggest that a BR to FPL tendon transfer surgery utilizing a force-amplifying pulley implant to augment force transmission can provide additional functional strength restoration over the standard procedure that directly sutures two tendons together.

Osteoplastic Thumb Reconstruction in the Immediate Setting: A Case Series.

Background: 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. Methods: 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. Results: 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. Conclusions: 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.

Surgical Technique for Concurrent Endoscopic Carpal Tunnel Release and Distal Radius Fracture Fixation Using the Flexor Carpi Radialis Approach: A Case Series.

Purpose: 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. Methods: We performed a retrospective, single-surgeon study of 17 consecutive adult patients (aged >18 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). Results: 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; P = .02). Conclusions: 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. Type of study/level of evidence: Therapeutic IV.

Surface Electromyography-Driven Therapeutic Gaming for Rehabilitation of Upper Extremity Weakness: A Pilot Study.

SUMMARY: 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. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Oral Health Service Access in Racial/Ethnic Minority Neighborhoods: A Geospatial Analysis in Washington, DC, USA.

Previous studies on individual-level variables have improved our knowledge base of oral health service use. However, environmental or contextual variables are also important in understanding oral health disparities in racial and ethnic neighborhoods. Based on Bronfenbrenner's ecological framework, this study examines the geographic availability of oral health providers in Washing-ton DC, U.S.A. Census tract-level data were drawn from the American Community Survey, joined with tract-level shapefiles, and overlaid with the geographic location of dental services throughout the city. Visual maps, descriptive statistics, and spatial lag regression models showed that census tracts with higher concentrations of African Americans were significantly farther from their nearest oral health providers (r = 0.19, p < 0.001), after controlling for neighborhood poverty rate, median age, and gender. Such findings confirm that in urban areas with highly di-verse populations such as Washington DC, racial disparities in oral health care access are signifi-cant. The study highlights that identifying neighborhoods with limited oral health care providers should be a priority in diminishing racial disparities in oral health service access. Improving access to racial/ethnic minority communities, especially African American neighborhoods, will require changes in health policies and programs, workforce development, resource allocation, community outreach, and educational programs.

Management of Artery-Only Digit Replantation: A Systematic Review of the Literature.

BACKGROUND: Artery-only replantation may be necessary in circumstances when venous repair cannot be performed due to their size or vessel injury. Venous congestion of the replanted part is inevitable. A systematic review was performed to identify techniques for mitigating congestion and analyze the outcomes of those techniques. METHODS: A comprehensive literature search was performed to identify relevant articles related to artery-only replantation. An initial query identified 1286 unique articles. A total of 55 articles were included in the final review. Included studies were categorized by decongestive technique. Data from each article included the number of patients treated, level of amputation, graft use, anticoagulation or antiplatelet therapy, replant viability, and follow-up duration. Weighted averages were determined from studies that reported five or more digits. RESULTS: A total of 1498 individual digital replantations were described. Very rarely did studies report artery-only replantation proximal to the distal interphalangeal joint. An overall survival rate of 78.5 percent was found irrespective of technique but was variable based on each particular study. Studies utilizing medicinal leech therapy were more likely to report use of intravenous anticoagulation, whereas surface bleeding techniques were more likely to report use of topical or local anticoagulant. CONCLUSIONS: Lack of a vein for anastomosis should not be regarded as a contraindication to replantation. These digits instead require a method to establish reliable drainage sufficient to allow for low resistance inflow and maintain a physiologic pressure gradient across capillary beds. The surgeon should select a decongestive technique that best suits the patient and their specific injury.

Using GIS to Analyze Inequality in Access to Dental Care in the District of Columbia.

BACKGROUND: Access to dental care in mixed-race and predominantly African American wards in the District of Columbia (DC) was investigated in relation to community development. METHODS: This study used high-resolution geographic information system (GIS) tools to map all general dentistry and periodontal practice locations in DC wards. The spatial analysis contextualized each ward's land use and demographic data obtained from DC government reports. FINDINGS: The analysis revealed inter-ward inequity in dental care access, which was measured by proximity to and number of dental clinics in each DC ward. Residents in affluent wards had access to many dental practices and superior amenities. Residents in wards poorly served by public transportation and with few resources had few, if any, dental clinics. CONCLUSIONS: Dental practices are inequitably distributed across DC wards. DC policy should prioritize community development-specifically, resource allocation and community outreach-to promote health equity and improve access to and quality of dental care among residents of color.

Nonsurgical Approaches to Neuroma Management.

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.

Occult primary breast cancer presenting with brachial plexopathy: A case report.

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.

Targeted Peripheral Nerve Interface: Case Report with Literature Review.

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.

Clinical supervision in frontline health care: A survey of social workers in Ontario, Canada.

Researchers have documented diminishing staff supervision in health care settings, while noting the complexity and dynamic nature of health care systems. A secondary data analysis of a survey of the Ontario Association of Social Workers (N=666) explored the contemporary receipt of different types of supervision in frontline health care. Most social worker participants were involved in supervision, receiving administrative and supportive supervision. Only 52% engaged in clinical supervision, even though most spent over 50% of work time with clients with complex needs. Factors related to the receipt of clinical supervision included setting, experience, gender, and availability of clinical practice leaders.

Stakeholder perspectives and sustainability of an integrated care model for the prevention and management of obesity: the Childhood Obesity Research Demonstration (CORD) project.

Although reliable strategies exist to promote healthy habits that reduce childhood obesity, the sustainability of these strategies remains an ongoing public health challenge. This study aimed to identify factors experienced in a large, multisite project aimed at reducing childhood obesity that might contribute to project sustainability. Hypothesized constructs underpinning sustainability included replicability, continuation of benefits, institutionalization, and community capacity. Key informants (n = 27) completed 60 min, in-depth interviews, which were audio recorded and transcribed. Transcripts were first coded using a combined deductive and inductive approach. Four major themes emerged (with numerous subthemes): developing partnerships, challenges to the sustainability of implemented programming, the importance of intervening in multiple settings, and ongoing implementation and evaluation strategies. Replicability of complex childhood obesity interventions is possible when there are strong partnerships. Benefits can continue to be conferred from programming, particularly when evidence-based strategies are used that employ best practices. Implementation is facilitated by institutionalization and policies that buffer challenges, such as staffing or leadership changes. Community capacity both enhances the sustainability of interventions and develops as a result of strengthening partnerships and policies that support childhood obesity programming.

A Multicenter Matched Cohort Study of Processed Nerve Allograft and Conduit in Digital Nerve Reconstruction.

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.

Evaluating sustainability in the Childhood Obesity Research Demonstration project: the model and process.

BACKGROUND: In the context of health-related interventions, sustainability is the capacity to maintain the changes resulting from the intervention. These can be improved policies, practices or trends intended to improve population health. The Childhood Obesity Research Demonstration (CORD) project was a multi-site, multi-intervention collaboration testing the Obesity Chronic Care Model with interventions for childhood obesity prevention and management. We present the model, definitions and methodology used for the cross-site sustainability evaluation of CORD. METHODS: We applied the Ecologic Model of Obesity to childhood obesity interventions to operationalize four sustainability constructs: replicability, continuation of benefits, institutionalization, and community capacity. We used a triangulation approach and employed mixed methods to assess sustainability constructs at each level of the Ecologic Model of Obesity: Micro, Meso, Exo and Macro. We constructed checklists to count and code intervention activities, use of evidence-based practices among providers, and environmental factors and policies hypothesized to influence intervention sustainability. We developed in-depth interviews for principal investigators and project leads. We applied the Wilder Collaboration Factors Inventory with key stakeholders. RESULTS: Lessons learned suggested that sustainability constructs should be clearly identified and operationalized a priori. Constructs must be flexible to account for differences between intervention plans and implementation to obtain robust and informative data. CONCLUSION: Strong links are needed among researchers, program implementers and communities to accomplish consistent, robust and valuable data collection efforts to assure sustainable and healthy communities.

Peripheral nerve repair throughout the body with processed nerve allografts: Results from a large multicenter study.

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 <15 mm and 50-70 mm gap subgroups, 91 and 69% MR, respectively (p = .01). Results were comparable to historical literature for nerve autograft and exceed that of conduit. CONCLUSIONS: These findings provide clinical evidence to support the continued use of PNA up to 70 mm in sensory, mixed and motor nerve repair throughout the body and across a broad patient population.

Brachial Plexus Desmoid Tumor: Care for Functional Preservation.

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 ß-catenin inhibitor and monitored with serial MRI.

Anterolateral thigh free flaps for the reconstruction of scalp angiosarcoma - 18-year experience in Chang Gung memorial hospital.

BACKGROUND: Scalp angiosarcoma is a rare and highly aggressive cutaneous malignancy with poor prognosis and high recurrence rate. Multimodality approach is currently the treatment protocol for resectable angiosarcoma, including wide local excision and postoperative radiation. This single-institution study reviews the 18-year experience of the surgical treatment of scalp angiosarcomas. METHODS: A retrospective chart review was performed on patients with scalp angiosarcoma who received wide local excision and free flap reconstruction from 2001 to 2018. The type of free flap, safety margin, outer cortex burring, and dose for radiation were recorded. Kaplan-Meier plots were computed. RESULTS: Eight male patients (mean age of 74.4 years old) were enrolled in the series. Tumor sizes ranged from 3 × 3 to 8 × 13 cm. All patients underwent wide local excision and outer cortex burring (cortical curettage). Seven (87.5%) scalp defects were reconstructed with anterolateral thigh free flap. All patients received adjuvant radiation therapy for tumor bed and margins. Chemotherapy was adopted for the management of local recurrence (37.5%) or distant metastasis (37.5%). The 2-year and 5-year survival rates are 72.9% and 38.9%, respectively, and 1-year and 2-year disease-free rates are 37.5% each. CONCLUSION: Scalp angiosarcoma is a rare and highly aggressive cutaneous malignancy with poor prognosis. Anterolateral thigh free flap is a good reconstructive option due to its ability to cover large cutaneous defects with minimal need for skin grafting. Multimodal treatment protocol, including wide local excision with cortical curettage, and adjuvant radiation (regular basis) and chemotherapy (local recurrence or distant metastasis) may offer improved 1-year survival rate (100%).

Expanding the Boundaries of RNA Sequencing as a Diagnostic Tool for Rare Mendelian Disease.

Gene-panel and whole-exome analyses are now standard methodologies for mutation detection in Mendelian disease. However, the diagnostic yield achieved is at best 50%, leaving the genetic basis for disease unsolved in many individuals. New approaches are thus needed to narrow the diagnostic gap. Whole-genome sequencing is one potential strategy, but it currently has variant-interpretation challenges, particularly for non-coding changes. In this study we focus on transcriptome analysis, specifically total RNA sequencing (RNA-seq), by using monogenetic neuromuscular disorders as proof of principle. We examined a cohort of 25 exome and/or panel "negative" cases and provided genetic resolution in 36% (9/25). Causative mutations were identified in coding and non-coding exons, as well as in intronic regions, and the mutational pathomechanisms included transcriptional repression, exon skipping, and intron inclusion. We address a key barrier of transcriptome-based diagnostics: the need for source material with disease-representative expression patterns. We establish that blood-based RNA-seq is not adequate for neuromuscular diagnostics, whereas myotubes generated by transdifferentiation from an individual's fibroblasts accurately reflect the muscle transcriptome and faithfully reveal disease-causing mutations. Our work confirms that RNA-seq can greatly improve diagnostic yield in genetically unresolved cases of Mendelian disease, defines strengths and challenges of the technology, and demonstrates the suitability of cell models for RNA-based diagnostics. Our data set the stage for development of RNA-seq as a powerful clinical diagnostic tool that can be applied to the large population of individuals with undiagnosed, rare diseases and provide a framework for establishing minimally invasive strategies for doing so.