The correlation of neurophysiological findings with clinical and functional status in patients following traumatic nerve injury

Bioengineered nerve conduits and wraps for peripheral nerve repair of the upper limb

BACKGROUND

Traumatic peripheral nerve injury is common and incurs significant cost to individuals and society. Healing following direct nerve repair or repair with autograft is slow and can be incomplete. Several bioengineered nerve wraps or devices have become available as an alternative to direct repair or autologous nerve graft. Nerve wraps attempt to reduce axonal escape across a direct repair site and nerve devices negate the need for a donor site defect, required by an autologous nerve graft. Comparative evidence to guide clinicians in their potential use is lacking. We collated existing evidence to guide the clinical application of currently available nerve wraps and conduits.

OBJECTIVES

To assess and compare the effects and complication rates of licensed bioengineered nerve conduits or wraps for surgical repair of traumatic peripheral nerve injuries of the upper limb. To compare effects and complications against the current gold surgical standard (direct repair or nerve autograft).

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search was 26 January 2022. We searched online and, where not accessible, contacted societies' secretariats to review abstracts from the British Surgical Society of the Hand, International Federation of Surgical Societies of the Hand, Federation of European Surgical Societies of the Hand, and the American Society for Peripheral Nerve from October 2007 to October 2018.

SELECTION CRITERIA

We included parallel group randomised controlled trials (RCTs) and quasi-RCTs of nerve repair in the upper limb using a bioengineered wrap or conduit, with at least 12 months of follow-up.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane procedures. Our primary outcomes were 1. muscle strength and 2. sensory recovery at 24 months or more. Our secondary outcomes were 3. British Medical Research Council (BMRC) grading, 4. integrated functional outcome (Rosén Model Instrument (RMI)), 5. touch threshold, 6. two-point discrimination, 7. cold intolerance, 8. impact on daily living measured using the Disability of Arm Shoulder and Hand Patient-Reported Outcome Measure (DASH-PROM), 9. sensory nerve action potential, 10. cost of the device, and 11. adverse events (any and specific serious adverse events (further surgery)). We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

Five studies involving 213 participants and 257 nerve injuries reconstructed with wraps or conduits (129 participants) or standard repair (128 participants) met the inclusion criteria. Of those in the standard repair group, 119 nerve injuries were managed with direct epineurial repair, and nine autologous nerve grafts were performed. One study excluded the outcome data for the repair using an autologous nerve graft from their analysis, as it was the only autologous nerve graft in the study, so data were available for 127 standard repairs. There was variation in the functional outcome measures reported and the time postoperatively at which they were recorded. Mean sensory recovery, assessed with BMRC sensory grading (range S0 to S4, higher score considered better) was 0.03 points higher in the device group (range 0.43 lower to 0.49 higher; 1 RCT, 28 participants; very low-certainty evidence) than in the standard repair group (mean 2.75 points), which suggested little or no difference between the groups, but the evidence is very uncertain. There may be little or no difference at 24 months in mean touch thresholds between standard repair (0.81) and repair using devices, which was 0.01 higher but this evidence is also very uncertain (95% confidence interval (CI) 0.06 lower to 0.08 higher; 1 trial, 32 participants; very low-certainty evidence). Data were not available to assess BMRC motor grading at 24 months or more. Repair using bioengineered devices may not improve integrated functional outcome scores at 24 months more than standard techniques, as assessed by the Rosén Model Instrument (RMI; range 0 to 3, higher scores better); the CIs allow for both no important difference and a better outcome with standard repair (mean RMI 1.875), compared to the device group (0.17 lower, 95% CI 0.38 lower to 0.05 higher; P = 0.13; 2 trials, 60 participants; low-certainty evidence). Data from one study suggested that the five-year postoperative outcome of RMI may be slightly improved after repair using a device (mean difference (MD) 0.23, 95% CI 0.07 to 0.38; 1 trial, 28 participants; low-certainty evidence). No studies measured impact on daily living using DASH-PROM. The proportion of people with adverse events may be greater with nerve wraps or conduits than with standard techniques, but the evidence is very uncertain (risk ratio (RR) 7.15, 95% CI 1.74 to 29.42; 5 RCTs, 213 participants; very low-certainty evidence). This corresponds to 10 adverse events per 1000 people in the standard repair group and 68 per 1000 (95% CI 17 to 280) in the device group. The use of nerve repair devices may be associated with a greater need for revision surgery but this evidence is also very uncertain (12/129 device repairs required revision surgery (removal) versus 0/127 standard repairs; RR 7.61, 95% CI 1.48 to 39.02; 5 RCTs, 256 nerve repairs; very low-certainty evidence).

AUTHORS' CONCLUSIONS

Based on the available evidence, this review does not support use of currently available nerve repair devices over standard repair. There is significant heterogeneity in participants, injury pattern, repair timing, and outcome measures and their timing across studies of nerve repair using bioengineered devices, which make comparisons unreliable. Studies were generally small and at high or unclear risk of bias. These factors render the overall certainty of evidence for any outcome low or very low. The data reviewed here provide some evidence that more people may experience adverse events with use of currently available bioengineered devices than with standard repair techniques, and the need for revision surgery may also be greater. The evidence for sensory recovery is very uncertain and there are no data for muscle strength at 24 months (our primary outcome measures). We need further trials, adhering to a minimum standard of outcome reporting (with at least 12 months' follow-up, including integrated sensorimotor evaluation and patient-reported outcomes) to provide high-certainty evidence and facilitate more detailed analysis of effectiveness of emerging, increasingly sophisticated, bioengineered repair devices.

Relationship Between Sensibility Tests and Functional Outcomes in Patients With Traumatic Upper Limb Nerve Injuries: A Systematic Review

Objective

To investigate which tests of hand sensibility correlate with functional outcomes in patients with upper limb traumatic nerve injuries and to assess if composite scales of sensibility correlate with functions.

Data Sources

MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were searched in May 2020, with a supplementary search in July 2020. Reference lists of the included publications were hand searched.

Study Selection

Database search found 2437 records. Eligible studies reported on inferential association between sensibility tests and functions pertaining to adults after upper limb nerve repair. Two reviewers independently assessed eligibility. Fifteen publications were included.

Data Extraction

Extracted data contain patient characteristics, surgical procedure, follow-up duration, sensibility tests, and functional assessments. Two reviewers independently assessed data quality.

Data Synthesis

Fifteen publications involving 849 patients were reviewed. All publications reported on median and/or ulnar nerve injuries. Monofilament tests correlated with Short-Form Health Survey (r=0.548, P<.05), pick-up test (r=0.45, P<.05), and function domain of Patient-Rated Wrist and Hand Evaluation Questionnaire (PRWHE) (r=0.58, P<.05). The 8 studies of static and moving 2-point discrimination provided conflicting correlations with activities of daily living (ADL) and/or the pick-up test. Data for area localization and object/shape identification were equivocal as well. No data were found for Ten test and vibration tests. Rosén score sensory domain correlated with ADL (r=0.59; 95% confidence interval [CI], 0.41-0.72) and PRWHE function domain (r=−0.56, P<.05). Medical Research Council sensory scale was related to pick-up test; return to work status; and Disabilities of the Arm, Shoulder, and Hand questionnaire.

Conclusions

Monofilament tests allow practitioners to gather sensibility data meaningful to patients’ overall recovery of functions after upper limb nerve trauma. For 2-point discrimination and other sensibility tests, practitioners should be aware that improvement in test performance does not necessarily translate to improved hand function. Findings from the composite scales indicate that hand sensibility, in general, is related to functions. Future research on other common sensibility tests is recommended to explore how the test relates to patients’ functions.

Evaluation of muscle strength following peripheral nerve surgery: A scoping review

Peripheral nerve injury (PNI) can result in devastating loss of function, often with poor long-term prognosis. Increased use of peripheral nerve surgical techniques (eg, nerve transfer, nerve grafting, and nerve repair) has resulted in improved muscle strength and other functional outcomes in patients with PNI. Muscle strength has largely been evaluated with the British Medical Research Council (MRC) scale. MRC is convenient to use in clinical settings, but more robust measures of muscle function are necessary to fully elucidate patient recovery. This scoping review aims to examine alternative instruments used to assess muscle function in studies of peripheral nerve surgery for PNI of the upper and lower limbs. A scoping review was conducted using Ovid MEDLINE, CINAHL, EMBASE, and PubMed databases in May and December of 2020, yielding a total of 20 studies pertaining to the review question. Studies pertaining to handheld dynamometry, grip and pinch dynamometry, Rotterdam Intrinsic Hand Myometers, isokinetic dynamometry, ultrasonography, and electromyography were reviewed. We provide a synopsis of each method and current clinical applications and discuss potential benefits, disadvantages, and areas of future research.

Treatment of elbow instability: state of the art

The elbow is a congruent joint with a high degree of inherent stability, provided by osseous and soft-tissue constraints; however, when substantial lesions of these stabilising structures happen, instability of the elbow occurs. Significant improvements in surgical elbow instability diagnosis and treatment have been recently introduced both for acute and chronic cases. Specific stress tests, recently introduced in the clinical practice, and different imaging techniques, both static and dynamic, allow assessment of the elbow stabilisers and detection of the instability direction and mechanism even in subtle forms. Many surgical techniques have been standardised and surgical instruments and devices, specifically dedicated to elbow instability treatment, have been developed. Specific rehabilitation protocols have been designed to protect the healing of the elbow stabilisers while minimising elbow stiffness. However, despite the progress, surgical treatments can be challenging even for expert surgeons and the rate of persistent instability, post-traumatic arthritis, stiffness and pain can be still high especially in most demanding cases. The biology of the soft-tissue healing remains one of the most important aspects for future investigation. If future research will help to understand, correct or modulate the biological response of soft-tissue healing, our confidence in elbow instability management and the reproducibility of our treatment will tremendously improve. In this paper, the state of the art of the current knowledge of elbow instability is presented, specifically focusing on modern surgical techniques used to solve instability, with repair or reconstruction of the damaged elbow stabilisers.

Role of nerve ultrasound versus electrophysiological studies in the evaluation of nerve injuries

Background

High-resolution ultrasonography (US) is a non-invasive, readily applicable imaging modality capable of depicting real-time static and dynamic information concerning the peripheral nerves and their surrounding tissues. Although electrophysiological studies are the gold standard in the evaluation of nerve injuries, US can be used also to evaluate the morphological changes of nerve injuries.

Objectives

To evaluate the role of the high-resolution US in the assessment of nerve injuries and to compare it to the role of electrodiagnostic studies.

Subjects and methods

A total of 30 nerves from 22 consecutive patients with clinically definite nerve injury were considered. Two independent and blinded clinicians perform electrodiagnosis and US. The clinical, neurophysiological, and US findings were collected, and the contribution of US was then classified as “ contributive” or “non-contributive”, according to whether US confirmed the clinical and neurophysiological diagnosis or not.

Results

US was “contributive” (confirming the electrophysiological diagnosis) in 66.67% of cases (n = 20), providing information about continuity of the nerve, morphological changes after injury as swelling, scar tissue formation, or neuroma formation with sensitivity of 75% compared to the electrodiagnostic studies and accuracy of 66.67%.

Conclusion

Ultrasound can be used, when available, as a complementary tool for electrodiagnostic studies to provide anatomical information about the injured nerves in case of complete axonal lesion.

Early rehabilitation of victims of traumatic ulnar injury using tendon transfer

BACKGROUND

Poor awareness among the patients and lack of resources for proper management of nerve injuries leads to delayed presentation of most traumatic ulnar nerve injuries. When this injury is present in the proximal forearm it leads to poor outcomes as Ulnar nerve repair with grafts takes a prolonged time to restore function. Addition of a tendon transfer to this procedure can allow patients to return to work earlier. The purpose of this study is to examine whether the addition of a tendon transfer to nerve repair surgery will lead to improved hand function and rehabilitation earlier than nerve grafting alone in cases of delayed presentation of Ulnar nerve injuries.

METHODS

A retrospective analysis of patients with traumatic ulnar nerve injury with duration of injury more than 1 month and location > 5 cm proximal to the flexor retinaculum who required a sural nerve graft for repair was done using Sollerman Hand Function test (SHFT). The SHFT scores were recorded for these patients at end of one year following repair with nerve grafting and status of employment at end of 6 and 12 month of surgery recorded as well. Another group of patients with traumatic ulnar injury of the same profile were given Fritchi tendon transfer along with sural nerve graft and followed up prospectively for a period of one year and SHFT score with status of employment recorded.

RESULTS

On comparison of employment status at 6 months we found that among the tendon transfer group 15/20 (75%) were employed while only 4/16 (20%) in the control group were able to return to work. Chi square test shows a p value of 0.002 (significant at p < 0.05). On evaluation at end of 1 year after surgery we found 18/20 (90%) had returned to work in the tendon transfer group while 8/16 (50%) had found employment again in the control group. Chi square test shows a p value 0.007 (significant at p < 0.05) CONCLUSION: These outcomes suggest that addition of a tendon transfer with nerve grafting promotes early rehabilitation, especially in patients employed in manual labor.

Prior to Repair Functional Deficits in Above- and Below-Elbow Ulnar Nerve Injury

PURPOSE

Clinical deficits might vary, depending on whether an ulnar nerve lesion is above or below the elbow. Lack of strength and clawing are common manifestations of ulnar nerve paralysis. However, the magnitude of strength deficit relating to different pinch patterns and the rate and range of proximal interphalangeal extension deficits are poorly described.

METHODS

I prospectively evaluated 14 patients with above-elbow and 16 with below-elbow unrepaired ulnar nerve injuries. The completeness of flexion of the ring and little fingers was tested at the metacarpophalangeal and distal interphalangeal joints. Proximal interphalangeal joint extension lag of the ring and little fingers was assessed by goniometry, and adduction and abduction of the little finger. With dynamometers, I bilaterally evaluated grasp, key pinch, and pinch-to-zoom strength. Hand sensibility was evaluated with monofilaments.

RESULTS

Metacarpophalangeal flexion in the ulnar fingers was absent in all patients, whereas distal interphalangeal joint flexion was preserved in 29 of 30 patients. In above-elbow ulnar nerve injuries, there was no paralysis of the flexor digitorum profundus. One-third of patients exhibited no clawing. There were minimal differences between the rate of clawing and proximal interphalangeal extension lag in above- and below-elbow ulnar nerve lesions, or its occurrence in the ring or little finger. In relation to the normal hand, grasping, key pinch, and pinch-to-zoom decreased by 62%, 51%, and 75% compared with 59%, 61%, and 76% in below- and above-elbow injuries groups, respectively. In both groups, sensory deficits were predominantly over the little finger and ulnar side of the hand.

CONCLUSIONS

Minimal differences were observed in clinical deficits after above- and below-elbow ulnar nerve injuries. Hand weakness was the most frequent problem, whereas pinch-to-zoom strength was highly affected.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic IV.

Distal pronator teres motor branch transfer for wrist extension restoration in radial nerve paralysis

OBJECTIVE

The authors describe the anatomy of the motor branches of the pronator teres (PT) as it relates to transferring the nerve of the extensor carpi radialis brevis (ECRB) to restore wrist extension in patients with radial nerve paralysis. They describe their anatomical cadaveric findings and report the results of their nerve transfer technique in several patients followed for at least 24 months postoperatively.

METHODS

The authors dissected both upper limbs of 16 fresh cadavers. In 6 patients undergoing nerve surgery on the elbow, they dissected the branches of the median nerve and confirmed their identity by electrical stimulation. Of these 6 patients, 5 had had a radial nerve injury lasting 7-12 months, underwent transfer of the distal PT motor branch to the ECRB, and were followed for at least 24 months.

RESULTS

The PT was innervated by two branches: a proximal branch, arising at a distance between 0 and 40 mm distal to the medial epicondyle, responsible for PT superficial head innervation, and a distal motor branch, emerging from the anterior side of the median nerve at a distance between 25 and 60 mm distal to the medial epicondyle. The distal motor branch of the PT traveled approximately 30 mm along the anterior side of the median nerve; just before the median nerve passed between the PT heads, it bifurcated to innervate the deep head and distal part of the superficial head of the PT. In 30% of the cadaver limbs, the proximal and distal PT branches converged into a single trunk distal to the medial epicondyle, while they converged into a single branch proximal to it in 70% of the limbs. The proximal and distal motor branches of the PT and the nerve to the ECRB had an average of 646, 599, and 457 myelinated fibers, respectively.All patients recovered full range of wrist flexion-extension, grade M4 strength on the British Medical Research Council scale. Grasp strength recovery achieved almost 50% of the strength of the contralateral side. All patients could maintain their wrist in extension while performing grasp measurements.

CONCLUSIONS

The distal PT motor branch is suitable for reinnervation of the ECRB in radial nerve paralysis, for as long as 7-12 months postinjury.

Management of Iatrogenic Nerve Injuries

Iatrogenic peripheral nerve injuries from orthopaedic surgery can occur via many scenarios, including direct injury to the nerve during surgery, indirect injury via retraction or compartment syndrome, and injury from nonsurgical treatments such as injections and splinting. Successful management of iatrogenic nerve injuries requires an accurate diagnosis and timely, appropriate treatment. All orthopaedic surgeons must understand the preclinical study of nerve injury and the evaluation and treatment options for iatrogenic nerve injuries. Although a sharply transected nerve can be repaired immediately in the operating room under direct visualization, many injuries are not appreciated until the postoperative period. Advances in diagnostic studies and nerve repair techniques, nerve grafting, and nerve transfers have improved our ability to identify and treat such injuries.

Functional, motor, and sensory assessment instruments upon nerve repair in adult hands: systematic review of psychometric properties

BACKGROUND

Outcome after nerve repair of the hand needs standardized psychometrically robust measures. We aimed to systematically review the psychometric properties of available functional, motor, and sensory assessment instruments after nerve repair.

METHODS

This systematic review of health measurement instruments searched databases from 1966 to 2017. Pairs of raters conducted data extraction and quality assessment using a structured tool for clinical measurement studies. Kappa correlation was used to define the agreement prior to consensus for individual items, and intraclass correlation coefficient (ICC) was used to assess reliability between raters. A narrative synthesis described quality and content of the evidence.

RESULTS

Sixteen studies were included for final critical appraisal scores. Kappa ranged from 0.31 to 0.82 and ICC was 0.81. Motor domain had manual muscle testing with Kappa from 0.72 to 0.93 and a dynamometer ICC reliability between 0.92 and 0.98. Sensory domain had touch threshold Semmes-Weinstein monofilaments (SWM) as the most responsive measure while two-point discrimination (2PD) was the least responsive (effect size 1.2 and 0.1). A stereognosis test, Shape and Texture Identification (STI), had Kappa test-retest reliability of 0.79 and inter-rater reliability of 0.61, with excellent sensibility and specificity. Manual tactile test had moderate to mild correlation with 2PD and SWM. Function domain presented Rosén-Lundborg score with Spearman correlations of 0.83 for total score. Patient-reported outcomes measurements had ICC of 0.85 and internal consistency from 0.88 to 0.96 with Patient-Rated Wrist and Hand Evaluation with higher score for reliability and Spearman correlation between 0.38 and 0.89 for validity.

CONCLUSIONS

Few studies included nerve repair in their sample for the psychometric analysis of outcome measures, so moderate evidence could be confirmed. Manual muscle test and Rotterdam Intrinsic Hand Myometer dynamometer had excellent reliability but insufficient data on validity or responsiveness. Touch threshold testing was more responsive than 2PD test. The locognosia test and STI had limited but positive supporting data related to validity. Rosén-Lundborg score had emerging evidence of reliability and validity as a comprehensive outcome following nerve repair. Few questionnaires were considered reliable and valid to assess cold intolerance. There is no patient-reported outcome measurement following nerve repair that provides comprehensive assessment of symptoms and function by patient perspective.

Transfer of the Motor Branch of the Abductor Digiti Quinti for Thenar Muscle Reinnervation in High Median Nerve Injuries

PURPOSE

In high median nerve repairs, thenar muscle reinnervation is impossible because of the long distances over which axons must regenerate. To overcome this obstacle, we propose transferring the abductor digiti quinti motor branch (ADQMB) to the thenar branch of the median nerve (TBMN).

METHODS

We used 10 embalmed hands for anatomical and histological studies. Thereafter, 5 patients with a high median nerve injury underwent surgical reconstruction within 8 months of their accident and were followed for at least 10 months after surgery (mean, 13.2 months). We transferred the ADQMB to the TBMN. The median nerve was grafted in 4 patients and the motor branch of the extensor carpi radialis brevis was transferred to the anterior interosseous nerve in 3. Patients had pre- and postoperative evaluations of thumb range of motion and strength.

RESULTS

In cadaveric hands, the ADQMB was the first branch of the ulnar nerve to arise near the pisiform bone. The TBMN arose from the anterior surface of the median nerve, underneath the flexor retinaculum. Retrograde dissection of the TBMN allowed tension-free coaptation with the ADQMB. Both branches contained approximately 650 myelinated fibers. After surgery, all our patients improved thumb pronation, thenar eminence bulk, and abductor pollicis brevis British Medical Research Council score. They recovered approximately 75% of their normal-side grasp and pinch strength. No patient lost little finger abduction.

CONCLUSIONS

Transfer of the ADQMB to the TBMN reinnervated the thenar muscles, which improved thumb range of motion and strength.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Electrophysiological Predictors of Clinical Outcome in Traumatic Neuropathies: A Multicenter Prospective Study

Objectives. This prospective, observational, multicentre study aims to identify electrodiagnostic (EDX) markers of clinical recovery in patients with traumatic neuropathy (TN) receiving surgical (S) and nonsurgical (NS) treatments. Methods. Subjects referred to the Italian Traumatic Neuropathy Network between 2010 and 2011 (307 patients, for a total of 444 TN) were evaluated with serial clinical/EDX evaluations at 6, 12, 24, and 36 months of follow-up. Results. Primary surgery was performed in 21 subjects with open lesions and evidence of neurotmesis, while closed lesions were treated with either conservative medical approach (216 patients) or secondary surgery (70 patients), according to the clinical spontaneous recovery at 4–6 months. Clinical improvement correlated with the increase of the compound muscle action potential amplitude (OR 3.76; CI 1.61–8.76), particularly in the S group (OR 7.25; CI 1.2–43.87), and with sensory nerve action potential amplitude in the NS group (OR 4.35; CI 1.14–16.69). No correlations were found with needle electromyography qualitative evaluations, changes in maximal voluntary recruitment, age, and gender. Conclusions. Nerve conduction studies (NCS) represent the more accurate neurophysiological markers of clinical outcome in patients with TN. Significance. Serial NCS assessments predict the functional recovery in TN, increasing the accuracy of peripheral nerves surgical decision-making process.

Ciguatoxin reduces regenerative capacity of axotomized peripheral neurons and delays functional recovery in pre-exposed mice after peripheral nerve injury

Ciguatera fish poisoning (CFP) results from consumption of tropical reef fish containing ciguatoxins (CTXs). Pacific (P)-CTX-1 is among the most potent known CTXs and the predominant source of CFP in the endemic region responsible for the majority of neurological symptoms in patients. Chronic and persistent neurological symptoms occur in some CFP patients, which often result in incomplete functional recovery for years. However, the direct effects of exposure to CTXs remain largely unknown. In present study, we exposed mice to CTX purified from ciguatera fish sourced from the Pacific region. P-CTX-1 was detected in peripheral nerves within hours and persisted for two months after exposure. P-CTX-1 inhibited axonal regrowth from axotomized peripheral neurons in culture. P-CTX-1 exposure reduced motor function in mice within the first two weeks of exposure before returning to baseline levels. These pre-exposed animals exhibited delayed sensory and motor functional recovery, and irreversible motor deficits after peripheral nerve injury in which formation of functional synapses was impaired. These findings are consistent with reduced muscle function, as assessed by electromyography recordings. Our study provides strong evidence that the persistence of P-CTX-1 in peripheral nerves reduces the intrinsic growth capacity of peripheral neurons, resulting in delayed functional recovery after injury.

Collagen Type I Conduits for the Regeneration of Nerve Defects

To date, reliable data to support the general use of biodegradable materials for bridging nerve defects are still scarce. We present the outcome of nerve regeneration following type I collagen conduit nerve repair in patients with large-diameter nerve gaps. Ten patients underwent nerve repair using a type I collagen nerve conduit. Patients were re-examined at a minimal follow-up of 14.0 months and a mean follow-up of 19.9 months. Regeneration of nerve tissue within the conduits was assessed by nerve conduction velocity (NCV), a static two-point discrimination (S2PD) test, and as disability of arm shoulder and hand (DASH) outcome measure scoring. Quality of life measures including patients’ perceived satisfaction and residual pain were evaluated using a visual analog scale (VAS). No implant-related complications were observed. Seven out of 10 patients reported being free of pain, and the mean VAS was 1.1. The mean DASH score was 17.0. The S2PD was below 6 mm in 40%, between 6 and 10 mm in another 40% and above 10 mm in 20% of the patients. Eight out of 10 patients were satisfied with the procedure and would undergo surgery again. Early treatment correlated with lower DASH score levels. The use of type I collagen in large-diameter gaps in young patients and early treatment presented superior functional outcomes.

Management of Iatrogenic Ulnar Nerve Transection

A case of iatrogenic ulnar nerve laceration at the elbow is presented. Five subsequent surgeries over the course of the ensuing 20 months were performed to address this complication. The article examines the scientific basis for the various decisions needed to formulate a strategy that effectively addresses the problem. Emphasis is placed on the microsurgery of nerve topics: direct nerve repair, autogenous cable nerve grafting, biodegradable conduits, decellularized nerve allograft, and transfer of the anterior interosseous nerve to the ulnar motor branch. The discussion covers the relationship between choices made at the level of the original injury at the cubital tunnel to the timing and selection of distal reconstructive efforts, with specific attention to the distinction between end-to-end anterior interosseous to ulnar motor branch transfer as opposed to the supercharged end-to-side variation of this procedure.