Development and validation of a new patient-reported outcome measure for peripheral nerve disorders of the hand, the I-HaND© Scale

Evaluating Outcomes Following Nerve Repair: Beyond the Medical Research Council

Peripheral nerve injuries are common and remain a significant health challenge. Outcome measurements are used to evaluate injury, monitor recovery after nerve repair, and compare scientific advances. Clinical judgement is required to determine which available tools are most applicable, which requires a vast understanding of the available outcome measurements. In this article we discuss the highest yield tools available for clinical application.

Distal Entrapment of Regenerating Peripheral Nerves After a Proximal Injury: A Case Series and Review of the Literature

A complication of peripheral nerve injuries, of which there exists limited discourse, is the entrapment of the nerve as it regenerates from the site of injury to its end target, resulting in the arrest of axon regeneration and a consequent reduction of functional recovery. This proof-of-concept paper reports a review of the relevant literature alongside a case series of patients who presented with this phenomenon and who were treated with targeted peripheral nerve decompression. Three cases were identified prospectively. The baseline function was recorded pre-and post-operatively. Recovery was assessed using various tools, including the Medical Research Council (MRC) motor grading, ten-test sensory testing, Tinel's sign progression, a visual analogue scale (VAS) for pain, and the Impact of Hand Nerve Disorders (I-HaND) patient-reported outcome measure (PROM). The first case sustained a brachial plexus injury and received decompression at the pronator fascia, carpal tunnel, cubital tunnel, and Guyon's canal. The second case sustained a sciatic nerve injury and was managed with peroneal and tarsal tunnel decompressions. The final case sustained a suprascapular nerve injury and underwent decompression at the suprascapular ligament. In all these cases, motor function, sensory function, and pain (depending on the nerve's original components) improved following decompression. A literature review revealed seven relevant studies, including four case reports, two cohort studies, and a pre-clinical animal study. These cases, and those identified in our review of the literature, suggest that targeted decompressive surgery can be an appropriate treatment for patients who display signs of stalled neural regeneration. This study adds to the limited evidence of this phenomenon and highlights the challenges in proving the efficacy of decompressive surgery for this specific complication. This study is limited by the number of cases included, the heterogeneity of nerve injuries presented, and its observational nature. There is a clear need for further research into this phenomenon, and the authors are working towards developing a prospective study that will investigate the indications, value, predictors of success, and practicality of decompression surgery for this complication of peripheral nerve injury.

Correlation of the I-HaND Scale with Other Musculoskeletal Patient-Reported Outcome Measurement Scores

Background  Experiments can determine if nerve-specific patient-reported outcome measures (PROMs) can outperform regional or condition-specific PROMs. We compared a nerve-specific PROM of the upper extremity, the Impact of Hand Nerve Disorders (I-HaND) scale, to other validated measures quantifying activity intolerance and sought to assess interquestionnaire correlations and factors independently associated with activity intolerance and pain intensity. Methods  One hundred and thirty patients with any upper extremity nerve-related condition completed measures of demographics, psychological limitations, quality of life, activity intolerance, and pain intensity. To quantify activity intolerance, we used the I-HaND, Patient-Reported Outcomes Measurement Information System Physical Function Upper Extremity, and Disabilities of the Arm, Shoulder and Hand short form. Results  Strong interquestionnaire correlations were found between the activity intolerance measures ( r between 0.70 and 0.91). Multivariable analysis revealed that greater activity intolerance and greater pain intensity correlated most with greater symptoms of depression on all scales, with symptoms of depression accounting for 53 to 84% of the variability in the PROMs. Conclusion  There is no clear advantage of the nerve-specific I-HaND over shorter, regional PROMs, perhaps because they are all so closely tied to mental health. Unless an advantage relating to responsiveness to treatment is demonstrated, we support using a brief arm-specific PROM for all upper extremity conditions. Level of Evidence  Level II; Prognostic.

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.

A Comparison of Nerve-Specific, Condition-Specific, and Upper Extremity-Specific Patient-Reported Outcome Measures in Patients With Carpal and Cubital Tunnel Syndrome

PURPOSE

Arm-, region-, tissue-, and condition-specific patient-reported outcome measures (PROMs) are available to address idiopathic mononeuropathy. This study compared PROMs with varying specificities in patients with idiopathic neuropathy of the upper extremity with respect to correlations with each another, sources of variation in scores, and floor and ceiling effects.

METHODS

One hundred fifty patients (130 with carpal tunnel syndrome, 30 with cubital tunnel syndrome, and 10 with both conditions) completed a nerve-specific PROM (Impact of Hand Nerve Disorders), a condition-specific PROM (Boston Carpal Tunnel Syndrome Questionnaire and/or Patient-Rated Ulnar Nerve Evaluation), and an upper extremity-specific PROM (Patient-Reported Outcomes Measurement Information System Physical Function Upper Extremity 7). We also gathered demographic and condition-related data (side, electrodiagnostic studies present, muscle atrophy, static loss of sensibility), and patients completed questionnaires measuring self-efficacy, kinesiophobia, and symptoms of depression. Correlation of the PROMs with each another and factors accounting for their variation were assessed, as well as the number of items to complete, time to complete, and floor and ceiling effects.

RESULTS

Pearson correlations between PROMs were moderate to strong (0.56-0.90). Self-reported symptoms of depression were best able to account for the variations in symptom intensity and activity intolerance on all PROMs (adjusted R² between 0.09 and 0.31). The Impact of Hand Nerve Disorders is a long questionnaire and took the most time to complete. All instruments had comparable floor effects; Patient-Reported Outcomes Measurement Information System Physical Function Upper Extremity had a ceiling of effect of 16%.

CONCLUSIONS

This study adds to the evidence that specific and general PROMs correlate with each another, perhaps in part through their correlation with mental health. Based on this line of evidence and pending testing of potentially greater responsiveness in specific settings, we prefer to use a single simple, brief, and general PROM to quantify symptom intensity and activity intolerance for both routine patient care and research.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.