Characterization of Spinal Cord Injury Patients for Arm Functional Restoration through Nerve Transfer.

INTRODUCTION: Traumatic spinal cord injuries (tSCI) are common, often leaving patients irreparably debilitated. Therefore, novel strategies such as nerve transfers (NT) are needed for mitigating secondary SCI damage and improving function. Although different tSCI NT options exist, little is known about the epidemiological and injury-related aspects of this patient population. Here, we report such characteristics to better identify and understand the number and types of tSCI individuals who may benefit from NTs. MATERIALS AND METHODS: Two peripheral nerve experts independently evaluated all adult tSCI individuals < 80 years old admitted with cervical tSCI (C1-T1) between 2005 and 2019 with documented tSCI severity using the ASIA Impairment Scale for suitability for NT (nerve donor with MRC strength ≥ 4/5 and recipient ≤ 2/5). Demographic, traumatic injury, and neurological injury variables were collected and analyzed. RESULTS: A total of 709 tSCI individuals were identified with 224 (32%) who met the selection criteria for participation based on their tSCI level (C1-T1). Of these, 108 (15% of all tSCIs and 48% of all cervical tSCIs) were deemed to be appropriate NT candidates. Due to recovery, 6 NT candidates initially deem appropriate no longer qualified by their last follow-up. Conversely, 19 individuals not initially considered appropriate then become eligible by their last follow-up. CONCLUSION: We found that a large proportion of individuals with cervical tSCI could potentially benefit from NTs. To our knowledge, this is the first study to detail the number of tSCI individuals that may qualify for NT from a large prospective database.

Barriers to Surgical Intervention and Factors Influencing Motor Outcomes in Patients with Severe Peripheral Nerve Injury: A Province Wide Cohort Study.

INTRODUCTION: Despite the importance of timing of nerve surgery after peripheral nerve injury, optimal timing of intervention has not been clearly delineated. The goal of this study is to explore factors that may have a significant impact on clinical outcomes of severe peripheral nerve injury that requires reconstruction with nerve transfer or graft. MATERIALS AND METHODS: Adult patients who underwent peripheral nerve transfer or grafting in Alberta were reviewed. Clustered multivariable logistic regression analysis was used to examine the association of time to surgery, type of nerve repair, and patient characteristics on strength outcomes. Cox proportional hazard regression analysis model was used to examine factors correlated with increased time to surgery. RESULTS: Of the 163 patients identified, the median time to surgery was 212 days. For every week of delay, the adjusted odds of achieving Medical Research Council strength grade ≥ 3 decreases by 3%. An increase in preinjury comorbidities was associated with longer overall time to surgery (aHR 0.84, 95% CI 0.74-0.95). Referrals made by surgeons were associated with a shorter time to surgery compared to general practitioners (aHR 1.87, 95% CI 1.14-3.06). In patients treated with nerve transfer, the adjusted odds of achieving antigravity strength was 388% compared to nerve grafting; while the adjusted odds decreased by 65% if the injury sustained had a pre-ganglionic injury component. CONCLUSION: Mitigating delays in surgical intervention is crucial to optimizing outcomes. The nature of initial nerve injury and surgical reconstructive techniques are additional important factors that impact postoperative outcomes.

Conditioning Electrical Stimulation Accelerates Regeneration in Nerve Transfers.

OBJECTIVE: Compared to the upper limb, lower limb distal nerve transfer (DNT) outcomes are poor, likely due to the longer length of regeneration required. DNT surgery to treat foot drop entails rerouting a tibial nerve branch to the denervated common fibular nerve stump to reinnervate the tibialis anterior muscle for ankle dorsiflexion. Conditioning electrical stimulation (CES) prior to nerve repair surgery accelerates nerve regeneration and promotes sensorimotor recovery. We hypothesize that CES prior to DNT will promote nerve regeneration to restore ankle dorsiflexion. METHODS: One week following common fibular nerve crush, CES was delivered to the tibial nerve in half the animals, and at 2 weeks, all animals received a DNT. To investigate the effects of CES on nerve regeneration, a series of kinetic, kinematic, skilled locomotion, electrophysiologic, and immunohistochemical outcomes were assessed. The effects of CES on the nerve were investigated. RESULTS: CES-treated animals had significantly accelerated nerve regeneration (p < 0.001), increased walking speed, and improved skilled locomotion. The injured limb had greater vertical peak forces, with improved duty factor, near-complete recovery of braking, propulsive forces, and dorsiflexion (p < 0.01). Reinnervation of the tibialis anterior muscle was confirmed with nerve conduction studies and immunohistochemical analysis of the neuromuscular junction. Immunohistochemistry demonstrated that CES does not induce Wallerian degeneration, nor does it cause macrophage infiltration of the distal tibial nerve. INTERPRETATION: Tibial nerve CES prior to DNT significantly improved functional recovery of the common fibular nerve and its muscle targets without inducing injury to the donor nerve. ANN NEUROL 2020;88:363-374.

Electrical stimulation enhances sensory recovery: a randomized controlled trial.

OBJECTIVE: Brief postsurgical electrical stimulation (ES) has been shown to enhance peripheral nerve regeneration in animal models following axotomy and crush injury. However, whether this treatment is beneficial in humans with sensory nerve injury has not been tested. The goal of this study was to test the hypothesis that ES would enhance sensory nerve regeneration following digital nerve transection compared to surgery alone. METHODS: Patients with complete digital nerve transection underwent epineurial nerve repair. After coaptation of the severed nerve ends, fine wire electrodes were implanted before skin closure. Postoperatively, patients were randomized to receiving either 1 hour of 20Hz continuous ES or sham stimulation in a double-blinded manner. Patients were followed monthly for 6 months by a blinded evaluator to monitor physiological recovery of spatial discrimination, pressure threshold, and quantitative small fiber sensory testing. Functional disability was measured using the Disability of Arm, Shoulder, and Hand questionnaire. RESULTS: A total of 36 patients were recruited, with 18 in each group. Those in the ES group showed consistently greater improvements in all sensory modalities by 5 to 6 months postoperatively compared to the controls. Although there was a trend of greater functional improvements in the ES group, it was not statistically significant (p > 0.01). INTERPRETATION: Postsurgical ES enhanced sensory reinnervation in patients who sustained complete digital nerve transection. The conferred benefits apply to a wide range of sensory functions.

Open Anterior Release of the Superior Transverse Scapular Ligament for Decompression of the Suprascapular Nerve During Brachial Plexus Surgery.

Reconstruction of the suprascapular nerve (SSN) after brachial plexus injury often involves nerve grafting or a nerve transfer. To restore shoulder abduction and external rotation, a branch of the spinal accessory nerve is commonly transferred to the SSN. To allow reinnervation of the SSN, any potential compression points should be released to prevent a possible double crush syndrome. For that reason, the authors perform a release of the superior transverse scapular ligament at the suprascapular notch in all patients undergoing reconstruction of the upper trunk of the brachial plexus. Performing the release through a standard anterior open supraclavicular approach to the brachial plexus avoids the need for an additional posterior incision or arthroscopic procedure.

Nerve Transfer Is Superior to Nerve Grafting for Suprascapular Nerve Reconstruction in Obstetrical Brachial Plexus Birth Injury: A Meta-Analysis.

BACKGROUND: Restoration of shoulder function in obstetrical brachial plexus injury is paramount. There remains debate as to the optimal method of upper trunk reconstruction. The purpose of this study was to test the hypothesis that spinal accessory nerve to suprascapular nerve transfer leads to improved shoulder external rotation relative to sural nerve grafting. METHODS: A systematic review of Medline, EMBASE, EBSCO CINAHL, SCOPUS, Cochrane Library, and TRIP Pro from inception was conducted. Our primary outcome was shoulder external rotation. RESULTS: Four studies were included. Nerve transfer was associated with greater shoulder external rotation relative to nerve grafting (mean difference: 0.82 AMS 95% confidence interval [CI]: 0.27-1.36, P < .005). Patients undergoing nerve grafting were more likely to undergo a secondary shoulder stabilizing procedure (odds ratio [OR]: 1.27, 95% CI: 0.8376-1.9268). CONCLUSION: In obstetrical brachial plexus injury, nerve transfer is associated with improved shoulder external rotation and a lower rate of secondary shoulder surgery. LEVEL OF EVIDENCE: Level III; Therapeutic.

Proximal Row Carpectomy Modifications for Capitate Arthritis: A Systematic Review.

Introduction Proximal row carpectomy (PRC) is a motion-sparing procedure for radiocarpal arthritis with reliable results. Traditionally, proximal capitate arthritis is a contraindication to PRC; however, PRC with modifications are proposed to circumvent this contraindication. PRC modifications can be broadly grouped into capitate resurfacing (CR) and capsular interposition (CI) procedures which could expand PRC indications. Our primary question was to characterize the outcomes achievable with various PRC modifications. Our secondary question was to determine which PRC modification was the optimal procedure when capitate arthritis was present. Methods A systematic review was conducted to examine the outcomes of modified PRC procedures. Independent reviewers appraised multiple databases for PRC studies with modifications for capitate arthritis in adult patients (age >18 years) with a minimum of three cases and extractable outcomes. Modified PRC procedures included capsular/allograft interposition, resurfacing capitate pyrocarbon implants, and osteochondral grafting. Pertinent outcomes included patient demographics, range-of-motion, grip strength, patient-reported outcomes, and complications, including salvage rates. Results Overall, 18 studies met the inclusion criteria-10 studies ( n = 147) on CI and 8 studies on CR ( n = 136). PRC with CI had the greatest flexion-extension arc and grip strength. Complications were marginally higher in the CR group (4%), while the CI group had a higher conversion to total wrist arthrodesis (10%). Conclusion Techniques to address capitate arthritis center around resurfacing or soft tissue interposition. PRC modifications with CI produces better range-of-motion and grip strength but higher conversion to total wrist arthrodesis. Higher conversion rates may be attributable to longer follow-up periods in studies examining CI compared with CR. Level of Evidence This is a Level III study.

Revisiting Lunotriquetral Arthrodesis in Chronic Lunotriquetral Ligamentous Injuries.

Background Chronic lunotriquetral (LT) ligament tears are a source of ulnar-sided wrist pain. Left untreated, complete tears of the LT ligament may progress to a volar intercalated segment instability deformity and eventual carpal arthritis. Various treatments have been proposed, one of which is LT arthrodesis. LT arthrodesis has been criticized for high rates of nonunion frequently requiring reoperation, and therefore has largely fallen out of favor. However, our experience has been quite different from the literature. This study examines a single surgeon's experience with LT arthrodesis over a 15-year period. Methods A retrospective review of the senior author's practice over a 15-year period was performed. All adult cases of LT arthrodesis for chronic LT injuries were included. Headless compression screw and cancellous bone graft from the distal radius were used for primary arthrodesis in all cases. The primary outcome was rate of union, and secondary outcomes were time to union, secondary or salvage procedures, and range of motion. Nonparametric statistical analysis was used to calculate differences in outcomes. Results Twenty-eight patients met inclusion criteria. The median age was 45.5 (interquartile range [IQR] 35-50) years and 75% were male. The dominant hand was most commonly affected. Eighty-six percent of patients achieved union, one patient required redo arthrodesis, and one patient went on to wrist salvage. Three patients developed a pain-free pseudoarthrosis. Median time to radiographic union was 8.8 (IQR 5.9-11.9) weeks. Conclusion Despite multiple previous reports, this study demonstrates that LT arthrodesis for chronic LT injuries is a safe technique with high rates of successful union. Further comparative studies are warranted to determine the optimal treatment for chronic LT injuries.

Reverse End-to-Side Nerve Transfer for Severe Ulnar Nerve Injury: A Western Canadian Multicentre Prospective Nonrandomized Cohort Study.

BACKGROUND: Reverse end-to-side (RETS) nerve transfer has become increasingly popular in patients with severe high ulnar nerve injury, but the reported outcomes have been inconsistent. OBJECTIVE: To evaluate the "babysitting effect," we compared outcomes after anterior interosseous nerve RETS transfer with nerve decompression alone. To evaluate the source of regenerating axons, a group with end-to-end (ETE) transfer was used for comparisons. METHODS: Electrophysiology measures were used to quantify the regeneration of anterior interosseous nerve (AIN) and ulnar nerve fibers while functional recovery was evaluated using key pinch and Semmes-Weinstein monofilaments. The subjects were followed postsurgically for 3 years. RESULTS: Sixty-two subjects (RETS = 25, ETE = 16, and decompression = 21) from 4 centers in Western Canada were enrolled. All subjects with severe ulnar nerve injury had nerve compression at the elbow except 10 in the ETE group had nerve laceration or traction injury. Postsurgically, no reinnervation from the AIN to the abductor digiti minimi muscles was seen in any of the RETS subjects. Although there was no significant improvement in compound muscle action potentials amplitudes and pressure detection thresholds in the decompression and RETS group, key pinch strength significantly improved in the RETS group ( P < .05). CONCLUSION: The results from published clinical trials are conflicting in part because crossover regeneration from the donor nerve has never been measured. Unlike those with ETE nerve transfers, we found that there was no crossover regeneration in the RETS group. The extent of reinnervation was also no different from decompression surgery alone. Based on these findings, the justifications for this surgical technique need to be carefully re-evaluated.

Validity and reliability of the Purdue Pegboard Test in carpal tunnel syndrome.

There is a paucity of validated tests to quantify hand function impairment due to carpal tunnel syndrome (CTS). The aim of this study was to test the validity and reliability of the Purdue Pegboard Test (PPT) in CTS patients. We compared 190 CTS patients with 122 healthy, age-matched controls. CTS severity was determined based on electrophysiologic parameters and the Levine Self-Assessment Questionnaire. The time to complete the PPT and the test-retest reliability were tested. The test-retest reliability was high with an intraclass correlation coefficient of 0.91. Compared to healthy controls, the CTS patients were significantly slower. Although the functional performance generally declined with increasing severity of electrophysiologic abnormalities, the correlation between hand function decline and symptom severity in the young and middle-aged groups was low. We conclude that the PPT is a valid and reliable tool to quantify functional impairment caused by CTS. It can be a useful outcome measure in young and middle-aged patients.

Discriminative validity and test-retest reliability of the Dellon-modified Moberg pick-up test in carpal tunnel syndrome patients.

There is a scarcity of validated hand performance tests with proven reliability for quantifying functional deficits in patients with carpal tunnel syndrome (CTS). The Dellon-modified Moberg pick-up test (DMMPUT), composed of commonly used daily objects, is potentially well suited for that purpose. This study was designed to evaluate the test-retest reliability and discriminative validity of the DMMPUT in CTS patients. We compared 162 CTS patients with 116 age-matched controls. CTS severity was determined based on electrophysiological parameters and Levine's Self-Assessment Questionnaire. The mean time to complete each subset of the DMMPUT by the CTS patients was compared with that by the healthy subjects. Test-retest reliability was examined in 46 CTS patients. Discriminative validity was demonstrated through a significant difference in test completion time between the CTS subjects and their age-matched controls. With few exceptions, the test scores declined with increasing severity of electrophysiological abnormalities and subjective symptom severity. Test-retest reliability of the DMMPUT was high with an intra-class correlation coefficient of 0.91. The DMMPUT has discriminative validity and high test-retest reliability in patients with CTS. It can be a useful standardized outcome measure to gauge disease severity.

Brachial Plexus Reconstruction Using Long Nerve Grafts as Spare Parts From an Amputated Limb: A Case Report.

CASE: The reconstruction of large nerve gaps remains a reconstructive challenge. Here, we present a case report of brachial plexus reconstruction using nerve grafts harvested as spare parts from an amputated limb. It also allowed us to use motor nerve grafts to reconstruct defects in the posterior cord and musculocutaneous nerve. The patient recovered good shoulder and elbow function at 2.5 years with evidence of innervation distally on electromyography. CONCLUSION: Spare part surgery should always be kept in a surgeons' reconstructive algorithm. Reconstruction of large nerve gaps can be achieved with autologous nerve grafts in certain circumstances.

Impacts of Rehabilitation Gait Training on Functional Outcomes after Tibial Nerve Transfer for Patients with Peroneal Nerve Injury: A Nonrandomized Controlled Trial.

BACKGROUND: Although there was initial success using tibial nerve transfer to restore ankle dorsiflexion following peroneal nerve injury, results from later series were less promising. A potential reason is coactivation of the much stronger antagonistic muscles during gait. The purpose of this study was to test the hypothesis that gait training would improve functional performance following tibial nerve transfer. METHODS: Using a prospective, nonrandomized, controlled study design, patients were divided into two groups: surgery only or surgery plus gait training. Of the 20 patients who showed reinnervation in the tibialis anterior muscle, 10 were assigned to the gait training group, and an equal number were in the control group. Those in the treatment group began training once reinnervation in the tibialis anterior muscle was detected, whereas those in the control group continued to use their ankle-foot orthosis full time. Differences in ankle dorsiflexion were measured using the Medical Research Council scale, and quantitative force measurement and functional disability was measured using the Stanmore Scale. RESULTS: Patients in the gait training group attained significantly better functional recovery as measured by the Stanmore Scale (79.5 ± 14.3) (mean ± SD) versus (37.2 ± 3.5) in the control group (p = 0.02). Medical Research Council grades were 3.8 ± 0.6 in the training group versus 2.5 ± 1.2 in the surgery only group (p < 0.05). Average dorsiflexion force from patients with above antigravity strength (all from the training group) was 31 percent of the contralateral side. CONCLUSION: In patients with successful reinnervation following tibial nerve transfers, rehabilitation training significantly improved dorsiflexion strength and function. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Postsurgical Electrical Stimulation Enhances Recovery Following Surgery for Severe Cubital Tunnel Syndrome: A Double-Blind Randomized Controlled Trial.

BACKGROUND: Patients with severe cubital tunnel syndrome often have poor functional recovery with conventional surgical treatment. Postsurgical electrical stimulation (PES) has been shown to enhance axonal regeneration in animal and human studies. OBJECTIVE: To determine if PES following surgery for severe cubital tunnel syndrome would result in better outcomes compared to surgery alone. METHODS: Patients with severe cubital tunnel syndrome in this randomized, double-blind, placebo-controlled trial were randomized in a 1:2 ratio to the control or stimulation groups. Control patients received cubital tunnel surgery and sham stimulation, whereas patients in the stimulation group received 1-h of 20 Hz PES following surgery. Patients were assessed by a blinded evaluator annually for 3 yr. The primary outcome was motor unit number estimation (MUNE) and secondary outcomes were grip and key pinch strength and McGowan grade and compound muscle action potential. RESULTS: A total of 31 patients were enrolled: 11 received surgery alone and 20 received surgery and PES. Three years following surgery, MUNE was significantly higher in the PES group (176 ± 23, mean + SE) compared to controls (88 ± 11, P < .05). The mean gain in key pinch strength in the PES group was almost 3 times greater than in the controls (P < .05). Similarly, other functional and physiological outcomes showed significantly greater improvements in the PES group. CONCLUSION: PES enhanced muscle reinnervation and functional recovery following surgery for severe cubital tunnel syndrome. It may be a clinically useful adjunct to surgery for severe ulnar neuropathy, in which functional recovery with conventional treatment is often suboptimal.

The Triceps Traction Test: A Decision Tool for the Choice of Stabilizing Flap After In Situ Decompression of the Ulnar Nerve.

PURPOSE: Recent evidence demonstrates that in situ decompression has comparable outcomes to other surgical techniques for cubital tunnel syndrome. However, this technique does not address the instability of the ulnar nerve, a common indication to transpose the ulnar nerve. Transposition of the ulnar nerve can potentially devascularize the ulnar nerve, stabilizing flaps block subluxation of the ulnar nerve and thereby negate the need for transposition. Flaps originating from the triceps and the flexor-pronator fascia could be used to stabilize the ulnar nerve. Herein, we present a novel intraoperative test, the "triceps traction test" and our algorithm for choosing a stabilizing flap when ulnar nerve instability is encountered after in situ decompression.

Acetyl-L-Carnitine to Enhance Nerve Regeneration in Carpal Tunnel Syndrome: A Double-Blind, Randomized, Controlled Trial.

BACKGROUND: Carpal tunnel syndrome is very common. Although surgery is effective in mild and moderate cases, recovery is often incomplete in severe cases. Therefore, adjuvant therapy to improve nerve regeneration in those patients is much needed. Acetyl-L-carnitine has been shown to be effective in other neuropathies. The goal of this study is to test the hypothesis that acetyl-L-carnitine can promote nerve regeneration and improve function in patients with severe carpal tunnel syndrome. METHODS: In this proof-of-principle, double-blind, randomized, placebo-controlled trial, adults with severe carpal tunnel syndrome were randomized to receive 3000 mg/day of acetyl-L-carnitine orally or placebo following carpal tunnel release surgery for 2 months. Outcomes were assessed at baseline and at 3, 6, and 12 months postoperatively. Symptom severity and functional outcomes were assessed using the Boston Carpal Tunnel Questionnaire and a wide range of physiologic and functional outcome measures. Patient safety was monitored by physical examination, blood work, and serum drug levels. The outcomes were analyzed using repeated measure two-way analysis of variance. RESULTS: Twenty patients with similar baseline characteristics were assigned randomly to the treatment or placebo group in a 1:1 ratio. Sixty percent were women with a mean age ± SD of 59 ± 2. The treatment was safe with no major adverse events reported. Although patients in both groups showed improvements postoperatively, there was no significant difference in any of the outcome measures between the groups. CONCLUSION: Although acetyl-L-carnitine was well tolerated, it did not improve nerve regeneration or functional recovery in patients with severe carpal tunnel syndrome. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Traumatic dislocation of the globe into the maxillary sinus.

CASE REPORT: We report a case of traumatic dislocation of the globe into the maxillary sinus following a bull-riding incident. COMMENTS: Traumatic dislocations of the eye into the sinuses are rare, and urgent management and surgical repair are indicated.

Needle Aponeurotomy for Dupuytren Disease.

Needle aponeurotomy is an effective, minimally invasive treatment for metacarpophalangeal and interphalangeal joint contractures caused by Dupuytren disease. Multiple joints and digits can be safely treated in 1 session. Needle aponeurotomy is more cost-effective and has a significantly lower complication rate compared with open fasciectomy and collagenase injections. Recurrence rates are higher compared with open fasciectomy and collagenase injections. Patient satisfaction rates are high following needle aponeurotomy; the single clinic visit required and the minimal downtime after treatment are advantages unique to this procedure compared with other treatment modalities, including open fasciectomy, dermatofasciectomy, collagenase injections, and lipofilling.