Digital nerve injuries: Epidemiology, results, costs, and impact on daily life

The effect of injury area on the success of treatment in digital nerve injury

INTRODUCTION

The main objective of the current study is to investigate variations in postoperative outcomes that follow digital nerve repair in Zone 1 and Zone 2, respectively. We hope that by carrying out this investigation, we will be able to identify which zone has better sensation recovery and patient-reported outcomes, allowing us to identify the best way of conducting surgery for specific types of injuries.

MATERIALS AND METHODS

A retrospective cohort study was conducted in patients with digital nerve injuries treated in a designated hand surgery clinic between January 2021 and December 2023. The study was guided by ethical consideration, where all participants gave their informed consent. Surgical interventions involved primary repair, autograft/allograft nerve grafting, nonsurgical approaches, as well as conduit repair in which results were determined using objective measures and patient feedback.

RESULTS

Direct repair emerged superior among injuries of Zone 1 and Zone 2 with high success rates and good patient-reported outcomes. In general, injuries in Zone 1 had better sensory recovery than injuries in Zone 2 and this was associated with higher levels of satisfaction. Comparisons using statistical methods confirmed that direct repair outperformed other modalities.

CONCLUSION

More importantly, the comparison of this study shows that repairs in Zone 1 are more successful than those in Zone 2 revealing direct repair as a superior method for digital nerve injuries. The difference is crucial because it suggests that surgical efficiency may depend on where the injury is. This means that direct repair should be given priority over the two zones, although surgeons will need to watch out for challenges related to Zone 2 injuries and adjust their strategies accordingly to obtain the best patient outcomes possible.

Photosealed Neurorrhaphy Using Autologous Tissue

Photochemical sealing of a nerve wrap over the repair site isolates and optimizes the regenerating nerve microenvironment. To facilitate clinical adoption of the technology, we investigated photosealed autologous tissue in a rodent sciatic nerve transection and repair model. Rats underwent transection of the sciatic nerve with repair performed in three groups: standard microsurgical neurorrhaphy (SN) and photochemical sealing with a crosslinked human amnion (xHAM) or autologous vein. Functional recovery was assessed at four-week intervals using footprint analysis. Gastrocnemius muscle mass preservation, histology, and nerve histomorphometry were evaluated at 120 days. Nerves treated with a PTB-sealed autologous vein improved functional recovery at 120 days although the comparison between groups was not significantly different (SN: -58.4 +/- 10.9; XHAM: -57.9 +/- 8.7; Vein: -52.4 +/- 17.1). Good muscle mass preservation was observed in all groups, with no statistical differences between groups (SN: 69 +/- 7%; XHAM: 70 +/- 7%; Vein: 70 +/- 7%). Histomorphometry showed good axonal regeneration in all repair techniques. These results demonstrate that peripheral nerve repair using photosealed autologous veins produced regeneration at least equivalent to current gold-standard microsurgery. The use of autologous veins removes costs and foreign body concerns and would be readily available during surgery. This study illustrates a new repair method that could restore normal endoneurial homeostasis with minimal trauma following severe nerve injury.

Revealing digital nerve lesions-A comprehensive analysis of 2084 cases of a specialized center

BACKGROUND

Finger nerve injuries have a significant impact on hand function and can result in reduced sensation, pain and impaired coordination. The socioeconomic implications of these injuries include decreased workplace productivity, reduced earning potential, and financial burdens associated with long-term medical treatment and rehabilitation. However, there is a lack of comprehensive literature regarding the incidence, mechanisms, and associated injuries of finger nerve lesions.

METHODS

A retrospective analysis was conducted on patients treated at our institution from January 2012 to July 2020. Cases of peripheral finger nerve lesions were identified using the digital hospital information system and ICD-10 Classification. Exclusion criteria included injuries to the median nerve at the carpal tunnel level or superficial branch of the radial nerve. Data were collected using a pseudonymized approach, and statistical analyses were performed using SPSS Statistics (Version 27).

RESULTS

A total of 2089 finger nerve lesions were analyzed, with a majority of cases occurring in men. Most injuries97.4 % were caused by trauma, predominantly cut/tear injuries. Isolated finger nerve injuries were more common than multiple nerve injuries, with the index finger being the most frequently affected. Concomitant tendon and vascular injuries were observed in a significant proportion51.7 % of cases. Surgical management included direct nerve coaptation, interposition grafting and neurolysis.

DISCUSSION

Finger nerve injuries are the most prevalent type of nerve injury, often resulting from small lacerations. These injuries have substantial societal costs and can lead to prolonged sick leave. Understanding the epidemiology and etiology of finger nerve injuries is crucial for implementing effective preventive measures. Accompanying tendon injuries and the anatomical location of the nerve lesions can impact sensory recovery and treatment outcomes. Proper management of peripheral finger nerve lesions is essential for optimizing functional outcomes and minimizing the impact on daily activities. Treatment options should be tailored to the severity and underlying cause of the nerve injury.

HOW TO PREVENT HAND INJURIES - REVIEW OF EPIDEMIOLOGICAL DATA IS THE FIRST STEP IN HEALTH CARE MANAGEMENT

BACKGROUND

Hand injuries are common affecting all ages, genders, and geographic regions. They can result in long term disability and mortality, while they place a significant financial burden in society. Although, hand injuries can be prevented. Preventive strategies can be designed, but knowledge of injuries' epidemiological characteristics is required beforehand.

METHODS

We performed a review of the current literature related to hand injuries to identify their incidence, patients' demographics, type, mode, and time of the injury.

RESULTS

Hand injuries constitute 6.6% to 28.6% of all injuries presenting to the Emergency Department and 28% of injuries to the musculoskeletal system. They mainly affect young male labourers. Occupational and home accidents are the commonest injury modalities, while traffic road accidents constitute a significant reason for hand injuries as well. Lacerations account for most hand injuries, followed by crush injuries, fractures and amputations. Most occupational injuries occur in the beginning of the week and especially during the morning shift, while there has been identified an increase in the number of hand injuries during the summer months.

CONCLUSIONS

Hand injuries are an important health problem with impact on patient's life and on the society. Although they can be prevented. Preventive strategies need to be addressed towards many directions and people's activities, since prevention will have an important impact on people's quality of life and society's well-being.

Application of Adipose Stem Cells in 3D Nerve Guidance Conduit Prevents Muscle Atrophy and Improves Distal Muscle Compliance in a Peripheral Nerve Regeneration Model

BACKGROUND

Peripheral nerve injuries (PNIs) represent a significant clinical problem, and standard approaches to nerve repair have limitations. Recent breakthroughs in 3D printing and stem cell technologies offer a promising solution for nerve regeneration. The main purpose of this study was to examine the biomechanical characteristics in muscle tissue distal to a nerve defect in a murine model of peripheral nerve regeneration from physiological stress to failure.

METHODS

In this experimental study, we enrolled 18 Wistar rats in which we created a 10 mm sciatic nerve defect. Furthermore, we divided them into three groups as follows: in Group 1, we used 3D nerve guidance conduits (NGCs) and adipose stem cells (ASCs) in seven rats; in Group 2, we used only 3D NGCs for seven rats; and in Group 3, we created only the defect in four rats. We monitored the degree of atrophy at 4, 8, and 12 weeks by measuring the diameter of the tibialis anterior (TA) muscle. At the end of 12 weeks, we took the TA muscle and analyzed it uniaxially at 10% stretch until failure.

RESULTS

In the group of animals with 3D NGCs and ASCs, we recorded the lowest degree of atrophy at 4 weeks, 8 weeks, and 12 weeks after nerve reconstruction. At 10% stretch, the control group had the highest Cauchy stress values compared to the 3D NGC group (0.164 MPa vs. 0.141 MPa, p = 0.007) and the 3D NGC + ASC group (0.164 MPa vs. 0.123 MPa, p = 0.007). In addition, we found that the control group (1.763 MPa) had the highest TA muscle stiffness, followed by the 3D NGC group (1.412 MPa), with the best muscle elasticity showing in the group in which we used 3D NGC + ASC (1.147 MPa). At failure, TA muscle samples from the 3D NGC + ASC group demonstrated better compliance and a higher degree of elasticity compared to the other two groups (p = 0.002 and p = 0.008).

CONCLUSIONS

Our study demonstrates that the combination of 3D NGC and ASC increases the process of nerve regeneration and significantly improves the compliance and mechanical characteristics of muscle tissue distal to the injury site in a PNI murine model.

Comparison of Functionality Level, Disability and Quality of Life in Subjects with Peripheral Nerve Repair in the Upper Extremity

Background

Peripheral nerve damage is a very important factor in patients' quality of life and functionality for various reasons. We aimed to compare the functionality level, disability and quality of life in subjects with peripheral nerve repair in the upper extremity.

Methods

This cross-sectional study was conducted on patients with nerve injuries in 2019. Among those patients, Eighty-five were selected as the sample. The instruments used in this study included the health-related quality of life standard questionnaire (SF-36), and the disability of the arm, shoulder and hand questionnaire (DASH-38). Data were analyzed by SPSS software version 22 and one-way ANOVA and Kruskal-Wallis statistical tests.

Results

Results of the Kruskal-Wallis test showed that the disability score in the groups of patients was not significant. In addition, according to the results of the one-way ANOVA test, the quality of life score was not significant among the patient groups.

Conclusion

Considering that peripheral nerve damage has a significant impact on patients' quality of life and functionality, apart from more research on the subject, it is necessary to provide support for patients to improve their quality of life.

Digital nerve injury: to repair or not?

BACKGROUND

There are very few studies comparing patients with and without repair after digital nerve injury. It is still controversial whether digital nerve repair is necessary.

AIMS

The aim of this study was to evaluate the long-term clinical outcomes of patients with unilateral isolated digital nerve injury who underwent surgical repair and those who did not.

METHODS

Seventy-four patients with unilateral digital nerve injury were included in the study. Of these, the patients who underwent surgical repair were determined as group A (n = 42), the patients without repair as group B (n = 32), and the groups were divided into subgroups according to injury levels. Results were evaluated with a minimum follow-up of 24 months.

RESULTS

When the S2PD results were evaluated overall, it was found that those who had digital nerve repair (group A) had significantly better outcomes compared to those without repair (group B) (p = 0.012). When the subgroups were evaluated according to the injury localization, no significant difference was observed at the distal levels, while it was observed that the patients who underwent repair in the proximal levels showed significantly better results (p = 0.003, p = 0.012).

CONCLUSION

In this study, it was seen that there was no difference between the results of repair and non-repair of unilateral nerve injuries distal to the middle level of the middle phalanx, but repair is required in injuries proximal to this level.

Precise Monitoring of Returning Sensation in Digital-Nerve Lesions by Three-Dimensional Imaging: A Proof-of-Concept Study

SUMMARY

Digital-nerve lesions result in a loss of tactile sensation reflected by an anesthetic area (AA) at the radial or ulnar aspect of the respective digit. Available tools to monitor the recovery of tactile sense have been criticized for their lack of validity. Precise quantification of AA dynamics by three-dimensional (3D) imaging could serve as an accurate surrogate to monitor recovery after digital-nerve repair. For validation, AAs were marked on digits of healthy volunteers to simulate the AA of an impaired cutaneous innervation. The 3D models were composed from raw images that had been acquired with a 3D camera to precisely quantify relative AA for each digit (3D models, n = 80). Operator properties varied with regard to individual experience in 3D imaging and image processing. In addition, the concept was applied in a clinical case study. Results showed that images taken by experienced photographers were rated as better quality ( P < 0.001) and needed less processing time ( P = 0.020). Quantification of the relative AA was not altered significantly, regardless of experience level of the photographer ( P = 0.425) or image assembler ( P = 0.749). The proposed concept allows precise and reliable surface quantification of digits and can be performed consistently without relevant distortion by lack of examiner experience. Routine 3D imaging of the AA has the great potential to provide visual evidence of various returning states of sensation and to convert sensory nerve recovery into a metric variable with high responsiveness to temporal progress.

Evaluation of Processed Nerve Allograft in Peripheral Nerve Surgery: A Systematic Review and Critical Appraisal

Peripheral nerve injuries cause substantial problems when not treated properly. A specific problem is reconstruction of nerve defects, which can be treated in different ways. This study aimed to systematically review whether processed nerve allograft (PNA) is justified in reconstruction of a nerve defect in patients after posttraumatic or iatrogenic peripheral nerve injury and to compare PNA with other established methods.

Methods

A systematic review with a focused question, PICO (patient, intervention, comparison, outcome) and constraints, was performed. A structured literature search, including several databases, was done to evaluate the existing evidence for outcomes and postoperative complications related to PNA. The certainty of evidence was classified according to Grading of Recommendations, Assessment, Development and Evaluations.

Results

No conclusions, concerning differences in outcome of nerve reconstruction using PNA compared with the use of nerve autograft or conduits, could be drawn. The level of certainty for all evaluated outcomes was very low (⊕◯◯◯). Most published studies lack a control group to patients treated with PNA; being only descriptive, making it difficult to compare PNA with established methods without substantial risk of bias. For studies including a control group, the scientific evidence was of very low certainty, due to a low number of included patients, and large, undefined loss of patients during follow-up, rendering a high risk of bias. Finally, the authors often had financial disclosures.

Conclusion

Properly conducted randomized controlled trial studies on the use of PNA in reconstruction of peripheral nerve injuries are needed to establish recommendations in clinical practice.

The incidence and management of peripheral nerve injury in England (2005-2020)

Peripheral nerve injury (PNI) is a significant health problem that confers lifelong impact on those injured. Current interventions are purely surgical; however, outcomes remain poor. There is a lack of high-quality epidemiological data that is needed to identify populations involved, current healthcare demands, and ensure resources are distributed to the greatest effect, to reduce the injury burden.

METHODS

Anonymized hospital episode statistical (HES) data on admitted patient care was obtained from NHS Digital for all National Health Service (NHS) patients sustaining PNI of all body regions between 2005 and 2020. Total numbers of finished consultant episodes (FCEs) or FCEs/100,000 population were used to demonstrate changes in demographic variables, anatomical locations of injury, mechanisms of injury, speciality, and main operation.

RESULTS

There was a mean national incidence of 11.2 (95% CI 10.9, 11.6) events per 100,000 population per year. Males were at least twice as likely (p < 0.0001) to sustain a PNI. Upper limb nerves at or distal to the wrist were most commonly injured. Knife injuries increased (p < 0.0001), whereas glass injuries decreased (p < 0.0001). Plastic surgeons increasingly managed PNI (p = 0.002) as opposed to orthopaedic surgeons (p = 0.006) or neurosurgeons (p = 0.001). There was an increase in neurosynthesis (p = 0.022) and graft procedures (p < 0.0001) during the study period.

DISCUSSION

PNI is a significant national healthcare problem predominantly affecting distal, upper limb nerves of men of working age. Injury prevention strategies, improved targeted funding and rehabilitation pathways are needed to reduce the injury burden and improve patient care.

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.

An Epidemiological and Etiological Analysis of 5026 Peripheral Nerve Lesions from a European Level I Trauma Center

Background: Peripheral nerve lesions are associated with debilitating long-term consequences. Albeit being essential for evidence-based clinical decision making, epidemiological and etiological data are scarce. We therefore aimed to comprehensively analyze epidemiological and etiological factors of peripheral nerve lesions in one of the largest cohorts. Methods: We screened a total of 110,667 patients treated at our level I trauma center between January 2012 and July 2020 for nerve lesions. Subsequently, demographics, etiologies, concomitant injuries, and lesion characteristics were analyzed. Results: A total of 5026 patients, predominantly young males suffering from non-work-related nerve injuries, were treated. Proximal levels of injury were more likely to be accompanied by fractures, whereas more distal injuries with concomitant vessel or tendon injury. Main causes were 54.6% lacerations. Acute traumatic nerve injury was treated within 24 h in 55.9% of cases. Conclusions: Given the young age of affected patients, early diagnosis and treatment in specialized centers may facilitate their early return to work and improve long-term functional outcomes. The data show the importance of a special attention on nerve injuries, which may be masked by large accompanying injuries. New findings on lesion characteristics of selected subgroups and accompanying circumstances can support a change in treatment strategies.

Total, gender- and age-specific incidence rates of upper extremity nerve injuries in Finland

The aim of this study was to describe the epidemiology of nerve injuries of the upper extremity in the whole population of Finland (1998-2016). Data based on diagnosis codes were obtained from the Care Register for Health Care, including cases of median, radial, ulnar, musculocutaneous, axillary and digital nerves. Age- and gender-specific incidence rates, both crude and standardized (for the European normal population in 2011), were calculated. Our study included 13,440 patients with upper extremity nerve injury. The mean standardized annual incidence rate of any upper extremity nerve injury was 18.18 among men and 8.15 among women per 100,000 person-years over the study period. The incidence peaked among men at working age. Nerve injuries occurred most commonly in the fingers and thumb, with 5532 cases and mean standardized incidence rates per 100,000 person-years of 7.84 among men and 2.95 among women. The annual incidence did not change significantly over the study period.Level of evidence: III.

Electric shock sign after digital nerve injury; report of a case and review of literature

INTRODUCTION AND IMPORTANCE

Digital nerve lacerations are rationally common, especially following penetrating injuries. The majority of patients suffer from numbness as the main complaint. However, electric shock pain is a rare manifestation of partial nerve injury.

CASE PRESENTATION

A 65-year-old woman with partial digital nerve injury and an electric shock sign due to a 1 cm laceration on the volar side of the proximal phalanx three weeks earlier. The surgical exploration revealed a neuroma-like mass in the digital nerve; however, the continuity of the nerve was grossly intact.

CLINICAL DISCUSSION

Due to the superficiality of digital nerves, penetrating nerve injuries are rationally common in this area. Laceration of the digital nerve could lead to loss of sensation, clumsiness, and even loss of function. Gradually, neuroma formation would add a local pain and electric shock sign to the mentioned symptoms.

CONCLUSION

Electric shock sign is characteristic for partial digital nerve injury with unknown mechanism. It seems the symptoms would be progressive and more complicated with neuroma formation.

LEVEL OF EVIDENCE

V.

Cold sensitivity, functional disability and predicting factors after a repaired digital nerve injury

To investigate self-reported cold sensitivity and functional disability after a repaired digital nerve injury. We identified 3204 individuals operated with digital nerve repair in the Swedish national quality registry for hand surgery (HAKIR). Patient-reported symptoms, including cold sensitivity and perceived disability, were examined using two questionnaires (HQ-8 and QuickDASH), three and 12 months postoperatively. Patients with diabetes (n = 48; 3%) were identified in the Swedish National Diabetes Register (NDR). Cold sensitivity (scored 0-100) was the most prominent symptom among 1553 included individuals (998 men, 555 women; median age 41 [IQR 27-54] years). In the regression analysis, flexor tendon injury, hand fracture and injury to multiple structures predicted worsened cold sensitivity (6.9, 15.5 and 25.0 points; p = 0.005, 0.046 and < 0.001) at 12 months. Individuals with moderate (30-70) and severe (> 70) cold sensitivity had higher QuickDASH scores at three and 12 months postoperatively than individuals with mild cold sensitivity (6.0 and 5.5; 19.8 and 21.0 points; p = 0.001). Flexor tendon injury, injuries to multiple structures and diabetes had significant effect on QuickDASH scores at three, but not at 12, months postoperatively. Cold sensitivity is common after a digital nerve repair and impacts self-reported disability. A concomitant injury, particularly multiple injuries, predicts postoperative cold sensitivity.

Cross-Sectional Evaluation of the Economic Burden on Patients Seeking Surgical Treatment for Chronic Nerve Injuries

INTRODUCTION

Little emphasis has been paid toward characterizing the socioeconomic burdens experienced by patients seeking treatment for chronic nerve injuries. The aim of this study was to characterize the direct and indirect costs faced by patients with chronic nerve injuries and their attendant health care utilization.

MATERIALS AND METHODS

A cross-sectional survey was distributed to all patients (N = 767) from a single nerve surgeon's practice treated for chronic nerve injuries in the ambulatory setting between 2014 and 2020. Data collected included demographics, etiology, comorbidities, duration and severity of symptoms, history of prior medical and interventional treatments, work or school time lost due to injury or treatment, money spent on treatment, and health care utilization.

RESULTS

Of the 767 patients, 209 (27.2%) completed the survey. Average age was 48.8 (SD = 19.1) years, 68.9% female and 31.1% male. Patients with chronic nerve injury reported significant direct costs, indirect costs, and health care utilization associated with their nerve injury symptoms. Direct costs consisted of out-of-pocket spending (68.4% had spent >$1000 per year), physician specialists visits (71.3% had seen at least 4 specialists), and prior interventional procedures intended to address symptoms. Indirect costs included lost time from work or school (24.6% had missed more than 12 months). Health care utilization, represented by annual emergency room visits and hospitalizations related to nerve symptoms, was increased relative to the general population. Detailed statistics are presented in the manuscript.

CONCLUSIONS

Chronic nerve injuries may be associated with a notable socioeconomic burden to the patient, including missed work or school, frequent physician visits and procedures, hospital visits, and out-of-pocket costs. Interdisciplinary algorithms recognizing a role for surgical evaluation in patients with chronic neuropathic pain due to underlying nerve injuries would facilitate future research into whether timely surgical intervention may reduce this economic burden.

Median and Digital Nerve In Situ Tension in the Hand

Background: Digital nerves will experience tension under normal daily activities, and understanding the amount of tension experienced in these nerves relates directly to the necessary strength in nerve repairs. To begin quantification of tension, the tension borne by the median and digital nerves in cadaveric hands was quantified under conditions of finger hyperextension, nerve distraction, and finger flexion. Methods: Five cadaveric hands were mounted in a special fixture that allowed finger hyperextension and flexion and could apply known distractions while the tension borne by each digital nerve was measured. Sequential dissection exposed the digital nerves so that measurements of tension in the median, common, and proper digital nerves were conducted with finger hyperextension, nerve distraction, and finger flexion. Results: Metacarpophalangeal (MCP) hyperextension of 30° created mean nerve tensions up to 0.64 N, 5 mm of nerve distraction created mean nerve tensions up to 1.23 N, and 90° of MCP flexion relieved up to a mean of 1.18 N of nerve tension. Conclusions: In situ tension is present in the median and digital nerves with digital motion. Finger hyperextension and nerve distraction produce tension, whereas finger flexion reduces tension. Existing nerve repairs are strong enough to withstand in situ nerve tensions produced by reasonable digital motion if the original nerve length is present.

Calcium homeostasis in parvalbumin DRG neurons is altered after sciatic nerve crush and sciatic nerve transection injuries

Reflex abnormalities mediated by proprioceptive sensory neurons after peripheral nerve injury (PNI) can limit functional improvement, leaving patients with disability that affects their quality of life. We examined postinjury calcium transients in a subpopulation of dorsal root ganglion (DRG) neurons consisting primarily of proprioceptors to determine whether alterations in calcium homeostasis are present in proprioceptors, as has been documented in other DRG neurons after PNI. Using transgenic mice, we restricted expression of the calcium indicator GCaMP6s to DRG neurons containing parvalbumin (PV). Mice of both sexes were randomly assigned to sham, sciatic nerve crush, or sciatic nerve transection and resuture conditions. Calcium transients were recorded from ex vivo preparations of animals at one of three postsurgery time points: 1-3 days, 7-11 days, and after 60 days of recovery. Results demonstrated that the post-PNI calcium transients of PV DRG neurons are significantly different than sham. Abnormalities were not present during the acute response to injury (1-3 days), but transients were significantly different than sham at the recovery stage where axon regeneration is thought to be underway (7-11 days). During late-stage recovery (60 days postinjury), disturbances in the decay time course of calcium transients in transection animals persisted, whereas parameters of transients from crush animals returned to normal. These findings identify a deficit in calcium homeostasis in proprioceptive neurons, which may contribute to the failure to fully recover proprioceptive reflexes after PNI. Significant differences in the calcium transients of crush versus transection animals after reinnervation illustrate calcium homeostasis alterations are distinctive to injury type.NEW & NOTEWORTHY This study examines calcium homeostasis after peripheral nerve injury in dorsal root ganglion (DRG) neurons expressing parvalbumin, a group of large-diameter afferents primarily consisting of proprioceptors, using two-photon calcium imaging in the intact DRG. Our findings identify aberrant calcium homeostasis as an additional source of sensory neuron dysfunction following peripheral nerve injury, uncover differences between two injury models, and track how these changes develop and resolve over the course of recovery.

Cost, profile, and postoperative resource use for surgically managed acute hand and wrist injuries with emergency department presentation

STUDY DESIGN

Retrospective cost-of-illness study.

INTRODUCTION

Injuries to the hand and wrist are common. Most uncomplicated and stable upper extremity injuries recover with conservative management; however, some require surgical intervention. The economic burden on the health care system from such injuries can be considerable.

PURPOSE OF THE STUDY

To estimate the economic implications of surgically managed acute hand and wrist injuries at one urban health care network.

METHODS

Using 33 primary diagnosis ICD-10 codes involving the hand and wrist, 453 consecutive patients from 2014 to 2015 electronic billing records who attended the study setting emergency department and received consequent surgical intervention and outpatient follow-up were identified. Electronic medical records were reviewed to extract demographic data. Costs were calculated from resource use in the emergency department, inpatient, and outpatient settings. Results are presented by demographics, injury type, mechanism of injury, and patient pathway.

RESULTS

Two hundred and twenty-six individuals (n 1⁄4 264 surgeries) were included. The total cost of all injuries was $1,204,606. The median cost per injury for non-compensable cases (n = 191) was $4508 [IQR $3993-$6172] and $5057 [IQR $3957-$6730] for compensable cases (n = 35). The median number of postoperative appointments with a surgeon was 2.00 (IQR 1.00-3.00) for both compensable and non-compensable cases. The number of hand therapy appointments for non-compensable cases and compensable cases was 4 [IQR 2-6] and 2 [IQR 1-3], respectively.

DISCUSSION

Findings of this investigation highlight opportunities for health promotion strategies for reducing avoidable injuries and present considerations for reducing cost burden by addressing high fail to attend (FTA) appointment rates.

CONCLUSION

Surgically managed hand and wrist injuries contribute to a significant financial burden on the health care system. Further research using stringent data collection methods are required to establish epidemiological data and national estimates of cost burden.

The effect of digital sensory loss on hand dexterity

The purpose of this study is to determine how loss of sensation affect hand dexterity. In this study, digital nerve block anaesthesia was performed in different stages of timing for thumb, index and middle fingers of 12 volunteers. The Moberg pick-up test was conducted in the assessment of hand dexterity. Grip and pinch forces were also measured. Loss of thumb sensation had the greatest effect on dexterity, increasing average timing by at least 10.5 seconds (range 3.4 to 32.4). Loss of sensation to the index and middle fingers has a lesser impact, but decreased hand grip and chuck pinch forces (grip -25% or -33%, chuck pinch -31% or -32% depending on the timing of injections). We concluded that loss of thumb sensation has the greatest impact on hand dexterity. Index and middle finger sensory loss had less of an impact on hand dexterity but decreased grip and chuck pinch forces.Level of evidence: IV.

Patterns of Peripheral Nerve and Tendon Injury in Hand Trauma Patients in a Tertiary Care Hospital of Pakistan

Introduction

Traumatic injury to peripheral nerves is a major medical problem worldwide. Moreover, injury to the hand and wrist can lead to extreme morbidity and disable the injured for life. In this study, we highlight the most commonly damaged nerves and tendons that get ruptured in different types of hand trauma patients. No recent study has been done to document the etiologies and quantify the patterns of nerve and tendon involvement in hand injuries to the best of our knowledge.

Methodology

This was a cross-sectional study conducted at the largest trauma center in the city and the Plastic and Reconstructive Surgery ward of Civil Hospital, Karachi. A convenient sampling of 200 patients was done with the help of a preformed, well-structured questionnaire. Patients whose hand was injured solely were included in the study and those with the involvement of the whole limb or other parts of the body were excluded.

Results

We found that most males between the ages of 11 and 20 years presented predominantly with right-hand injury while working with machines. Nerve injury proved to be a rare occurrence. However, combined nerve injury of the ulnar, median, and radial nerve was seen in poly digit trauma. The median nerve was the most commonly damaged nerve in poly digit trauma. Among the tendon injuries, the incidence of combined tendon injury was the greatest. The flexor digitorum superficialis was the most common tendon injured overall.

Conclusion

This study significantly states that tendons are frequently injured in hand accidents. Plastic surgeons must also be aware of optimal nerve repair and reconstruction techniques to limit the physical disabilities and economic burden arising from nerve injury of the dominant hand.

Effective decellularization of human nerve matrix for regenerative medicine with a novel protocol

Injuries to the peripheral nerves represent a frequent cause of permanent disability in adults. The repair of large nerve lesions involves the use of autografts, but they have several inherent limitations. Overcoming these limitations, the use of decellularized nerve matrix has emerged as a promising treatment in tissue regenerative medicine. Here, we generate longer human decellularized nerve segments with a novel decellularization method, using nonionic, zwitterionic, and enzymatic incubations. Efficiency of decellularization was measured by DNA quantification and cell remnant analysis (myelin, S100, neurofilament). The evaluation of the extracellular matrix (collagen, laminin, and glycosaminoglycans) preservation was carried out by enzyme-linked immunosorbent assay (ELISA) or biochemical methods, along with histological and immunofluorescence analysis. Moreover, biomechanical properties and cytocompatibility were tested. Results showed that the decellularized nerves generated with this protocol have a concentration of DNA below the threshold of 50 ng/mg of dry tissue. Furthermore, myelin, S100, and MHCII proteins were absent, although some neurofilament remnants could be observed. Moreover, extracellular matrix proteins were well maintained, as well as the biomechanical properties, and the decellularized nerve matrix did not generate cytotoxicity. These results show that our method is effective for the generation of decellularized human nerve grafts. The generation of longer decellularized nerve segments would allow the understanding of the regenerative neurobiology after nerve injuries in both clinical assays and bigger animal models. Effective decellularization of human nerve matrix for regenerative medicine with a novel protocol. Combination of zwitterionic, non-ionic detergents, hyperosmotic solution and nuclease enzyme treatment remove cell remnants, maintain collagen, laminin and biomechanics without generating cytotoxic leachables.

Chronic neuropathic pain after traumatic peripheral nerve injuries in the upper extremity: prevalence, demographic and surgical determinants, impact on health and on pain medication

Background and aims Aside from the long term side effects of a nerve injury in the upper extremity with devastating consequences there is often the problem of chronic neuropathic pain. The studies concerning the prevalence of persistent pain of neuropathic origin after peripheral nerve injuries are sparse. The prevalence and risk factors associated with chronic neuropathic pain after nerve injuries in the upper extremity were assessed. Methods A standardized data collection template was employed prospectively and retrospectively for all patients with traumatic nerve injuries accepted at the Hand Surgery Department, Uppsala, Sweden between 2010 and 2018. The template included demographic data, pain diagnosis, type of injured nerve, level of injury, date of the lesion and repair, type of procedure, reoperation, time since the procedure, S-LANSS questionnaire (Self report-Leeds Assessment of Neuropathic Symptoms and Signs), RAND-36 (Item short form health survey), QuickDASH (Disability of Shoulder, Arm and Hand) and additional questionnaires concerned medication, pain intensity were sent to 1,051 patients with nerve injuries. Partial proportional odds models were used to investigate the association between persistent pain and potential predictors. Results More than half of the patients undergoing a surgical procedure developed persistent pain. Prevalence of neuropathic pain was 73% of the patients with pain (S-LANSS ≥ 12 or more). Multivariate analysis indicated that injury of a major nerve OR 1.6 (p = 0.013), years from surgery OR 0.91 (p = 0.01), younger age OR 0.7 (p < 0.001), were the main factors for predicting pain after surgery. The type of the nerve injured was the strongest predictor for chronic pain with major nerves associated with more pain (p = 0.019). Conclusions A high prevalence of chronic pain and neuropathic pain with a negative impact on quality of life and disability were found in patients after traumatic nerve injury. Major nerve injury, younger age and less time from surgery were predictors for chronic pain.

Effect of Systemic Adipose-derived Stem Cell Therapy on Functional Nerve Regeneration in a Rodent Model

Supplemental Digital Content is available in the text.

Regardless of etiology, peripheral nerve injuries (PNI) result in disruption/loss of neuromuscular junctions, target muscle denervation, and poor sensorimotor outcomes with associated pain and disability. Adipose-derived stem cells (ASCs) have shown promise in neuroregeneration. However, there is a paucity of objective assessments reflective of functional neuroregeneration in experimental PNI. Here, we use a multimodal, static, and dynamic approach to evaluate functional outcomes after ASC therapy in a rodent PNI model.

Electrical stimulation to enhance peripheral nerve regeneration: Update in molecular investigations and clinical translation

Peripheral nerve injuries are common and frequently result in incomplete functional recovery even with optimal surgical treatment. Permanent motor and sensory deficits are associated with significant patient morbidity and socioeconomic burden. Despite substantial research efforts to enhance peripheral nerve regeneration, few effective and clinically feasible treatment options have been found. One promising strategy is the use of low frequency electrical stimulation delivered perioperatively to an injured nerve at the time of surgical repair. Possibly through its effect of increasing intraneuronal cyclic AMP, perioperative electrical stimulation accelerates axon outgrowth, remyelination of regenerating axons, and reinnervation of end organs, even with delayed surgical intervention. Building on decades of experimental evidence in animal models, several recent, prospective, randomized clinical trials have affirmed electrical stimulation as a clinically translatable technique to enhance functional recovery in patients with peripheral nerve injuries requiring surgical treatment. This paper provides an updated review of the cellular physiology of electrical stimulation and its effects on axon regeneration, Level I evidence from recent prospective randomized clinical trials of electrical stimulation, and ongoing and future directions of research into electrical stimulation as a clinically feasible adjunct to surgical intervention in the treatment of patients with peripheral nerve injuries.

Impact of Handedness on Disability After Unilateral Upper-Extremity Peripheral Nerve Disorder

Background: Impairment of the dominant hand should lead to greater disability than impairment of the nondominant hand, but few studies have tested this directly, especially in the domain of upper-extremity peripheral nerve disorder. The aim of this study was to identify the association between hand dominance and standardized measures of disability and health status after upper-extremity peripheral nerve disorder. Methods: An existing database was reanalyzed to identify the relationship between affected-side (dominant vs nondominant) on individuals with unilateral upper-extremity peripheral nerve disorder (N = 400). Primary measure of disability was the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire. Results: We found no differences in standardized measures of disability or health status between patients with affected dominant hand and patients with an affected nondominant hand. However, a post hoc exploratory analysis revealed that patients with an affected dominant hand reported substantially reduced ability to perform 2 activities in the DASH questionnaire: "write" and "turn a key." Conclusions: Following unilateral upper-extremity peripheral nerve disorder, impairment of the dominant hand (compared with impairment of the nondominant hand) is associated with reduced ability to perform specific activities, but this reduced ability is not reflected in standardized measures of disability and health status. To adequately identify disability following unilateral impairment of the dominant hand with the DASH, individual items must be used instead of the total score. New or alternative measures are also recommended.

Acute and long-term costs of 268 peripheral nerve injuries in the upper extremity

Background

Peripheral nerve injury in the upper extremity is linked to high socioeconomic burden, yet cost-analyses are rare and from small cohorts. The objective of this study was to determine the costs and long-term socioeconomic effects of peripheral nerve injuries in the upper extremity in Germany.

Methods

We analyzed data of 250 patients with 268 work-related upper extremity nerve injuries from acute treatment to long-term follow-up on rehabilitation, sick-leave and disability-pension.

Results

Patients were on average 39.9±14.2 years old, male (85%) and mean inpatient treatment was 7±6 days. Location of nerve was 8% (N = 19) proximal to the wrist, 26% (N = 65) at the wrist and metacarpus, and 66% (N = 166) at phalangeal level. Acute in-patient treatment for (single) median nerve injury accounted for 66% with hospital reimbursement of 3.570€, ulnar nerve injury for 24% and 2.650€ and radial nerve injury for 10% and 3.166€, all including finger nerve injuries. The remaining were combined nerve injuries, with significantly higher costs, especially if combined with tendon 5.086€ or vascular injury 4.886€. Based on location, nerve injuries proximal to the wrist averaged 5.360±6.429€, at the wrist and metacarpus 3.534±2.710€ and at the phalangeal level 3.418±3.330€. 16% required rehabilitation with average costs of 5.842€ and stay of 41±21 days. Sick leave was between 11–1109 days with an average of 147 days with socioeconomic costs of 197€/day, equaling on average 17.640€. 30% received a mean yearly disability pension of 3.187€, that would account to 102.167€ per lifetime.

Conclusion

This large German patient sample indicates that nerve injury has a major impact on function and employment, resulting in significant health care costs. Both proximal and distal nerve injuries led to long-term disability, subsequent sick-leave and in 30% to permanent disability pension. These data are determined to support future studies and health economical work on prevention, treatment and rehabilitation of these often small injuries with great consequences.

The Utility of Diagnostic Tests for Digital Nerve Injury

PURPOSE

The purpose of this study was to present the sensitivity and specificity of 6 clinical tests for the diagnosis of digital nerve injury. The clinical tests are as follows: light touch, pinprick, static and dynamic 2-point discrimination (D2PD), Semmes-Weinstein monofilament, and wrinkle test.

METHODS

We reviewed the charts of all the patients who were admitted to our department with hand lacerations and/or suspicions of digital nerve injury that were examined before surgery with the 6-sensation test, comparing the results to the surgical findings.

RESULTS

The study included 70 patients with 85 injured nerves overall. Of the 85 nerves, 51 were found with full cut, 9 with partial cut, and 25 with no cut. Only 2 variables were significantly associated with the study outcome: D2PD > 4 (P = 0.0141, odds ratio = 3.9, 95% confidence interval = 1.3-11.8, sensitivity = 80.7%, specificity = 48%) and wrinkle test (P = 0.0098, odds ratio = 4.0, 95% confidence interval = 1.4-11.6, sensitivity = 69.5%, specificity = 62.5%).Multivariable logistic regression included these variables and revealed the predictive probability for a nerve injury to be 92% if both risk factors exist and 43% if none of these risk factors exist. If one risk factor exists, the predictive probability for a cut is still very high (75%).

CONCLUSIONS

The combination of positive wrinkle test and D2PD > 4 gave a predictive probability for a nerve injury as 92% in the cases in our study and should be considered in the evaluation of patients with hand lacerations and suspicions of digital nerve injury.

Self-Assembling Peptide Hydrogel Matrices Improve the Neurotrophic Potential of Human Adipose-Derived Stem Cells

Despite advances in microsurgical techniques, treatment options to restore prior function following peripheral nerve injury remain unavailable, and autologous nerve grafting remains the therapy of choice. Recent experimental work has focused on the development of artificial constructs incorporating smart biomaterials and stem cells, aspiring to match/improve the outcomes of nerve autografting. Chemically stimulated human adipose-derived stem cells (dhASC) can improve nerve regeneration outcomes; however, these properties are lost when chemical stimulation is withdrawn, and survival rate upon transplantation is low. It is hypothesized that interactions with synthetic hydrogel matrices could maintain and improve neurotrophic characteristics of dhASC. dhASC are cultured on PeptiGel-Alpha 1 and PeptiGel-Alpha 2 self-assembling peptide hydrogels, showing comparable viability to collagen I control gels. Culturing dhASC on Alpha 1 and Alpha 2 substrates allow the maintenance of neurotrophic features, such as the expression of growth factors and neuroglial markers. Both Alpha 1 and Alpha 2 substrates are suitable for the culture of peripheral sensory neurons, permitting sprouting of neuronal extensions without the need of biological extracellular matrices, and preserving neuronal function. PeptiGel substrates loaded with hdASC are proposed as promising candidates for the development of tissue engineering therapies for the repair of peripheral nerve injuries.

The Electric Shock Sign-An Indication of a Partial Digital Nerve Laceration: A Report of Three Cases

CASE

Digital nerves injuries following penetrating injuries, lacerations, and blunt force trauma are common. This case series reports 3 acute cases of partial digital nerve lacerations where patients presented with a similar electric shock-like sensation, the "electric shock sign" radiating distally along the digital nerve distribution. The lancinating pain commonly occurs with active or passive finger extension. All 3 patients underwent operative repair of the digital nerve lacerations. With follow-up ranging between 4.5 months and 11 years, there was complete resolution of their pain.

CONCLUSIONS

The electric shock clinical sign can be an indicator of a partial digital nerve laceration.

Outcomes of surgical repair of a single digital nerve in adults

Current standard management of a cut digital nerve is end-to-end microsurgical nerve coaptation where possible. A recent systematic review of adult digital nerve injuries that were either repaired or left unrepaired showed that the evidence for good nerve recovery or improved function following nerve repair is poor. In the 30 studies included, only 24% of repaired nerves regained sensory recovery close to or equivalent to estimated pre-injury levels. Neuroma rates were the same in those nerves repaired (4.6%) and those not repaired (5%). Questions under debate include proper assessment methods of outcomes, decision making for repair or no repair to different fingers or the thumb, levels of injury, age, and hand dominance. This review summarizes the major evidence available and debates the surgical dogma that surrounds this injury.

Can the amniotic membrane be used to treat peripheral nerve defects? A review of literature

Human amniotic membrane is currently being used in ophthalmology and dermatology applications. The objective of this review was to establish proof-of-concept for using amniotic membrane to treat peripheral nerve defects. We performed a search using: 1) PubMed with the keywords/MeSH terms: "amnion", "amniotic membrane", "angiogenesis", "anti-microbial", "characteristic", "chorion", "epithelialization", "fibrosis", "gap", "growth factors", "use", "nerve"; 2) the American clinical trials registry with "amniotic membrane"; 3) Lim Jeremy's book "A primer on amniotic membrane regenerative healing"; 4) the search engine Google. Our findings pointed to the amniotic membrane being a biodegradable and bioactive scaffold that contains many growth factors important for efficient nerve regeneration. Multiple animal studies and the single human clinical trial performed up to now have highlighted its role in preventing recurrence of perineural adhesions, reducing fibrosis, accelerating nerve repair and improving nerve function. Thus, the amniotic membrane has ideal properties for treating peripheral nerve injuries. It could very likely prevent neuroma formation. The best format would be a freeze-dried one containing the amnion and chorion layers in order to preserve all its growth factors, and facilitate its handling and storage in the operating room.

The changing shape of hand trauma: an analysis of Hospital Episode Statistics in England

Hospital Episode Statistics (HES) include freely accessible records of all hospital episodes in England. We analysed HES from 1998-1999 to 2014-2015 for diagnoses of hand fractures, tendon injuries, nerve injuries, blood vessel injuries, traumatic amputations and nail bed injuries. Population data were used to calculate the incidence. The overall incidence of the injuries increased from 70 to 110 per 100,000. There were especially large increases in the incidence of fractures in the over 75 years age group and nail bed injuries in the 0-14 years age group. The incidence of nerve injuries also increased. We conclude from this study that HES is a useful tool. The information from HES may help plan service provision and also highlight important clinical problems that may benefit from further research.

Outcome of surgical repair of adult digital nerve injury: a systematic review

OBJECTIVES

A systematic review to assess the evidence supporting surgical repair of digital nerve injury versus no repair in adults in terms of clinical outcomes.

DESIGN

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses-compliant systematic review with methodology based on the Cochrane Handbook of Systematic Reviews of Interventions.

DATA SOURCES

Databases included OvidMEDLINE, EMBASE, AMED, clinicaltrials.gov and the Cochrane Database of Systematic Reviews, searched from inception until 10 November 2018.

ELIGIBILITY CRITERIA

Adult digital nerve injury in which either direct repair or no repair was undertaken and an outcome measure was recorded.

DATA EXTRACTION AND SYNTHESIS

Study data extracted included demographics, injury type and extent, timing, treatment details, outcome data and time points, adverse outcomes, hand therapy and return to work. The National Institute of Health quality assessment tool for case series was used to assess risk of bias.

RESULTS

Thirty studies were included. One compared surgical repair with non-repair. All studies were case series of between 15 and 110 nerve injuries, with heterogeneous patient, injury and treatment characteristics. Two studies detailed nerve repair without magnification. Static 2-point discrimination (s2PD) was the most commonly reported outcome measure. Return of protective sensation was achieved in most cases in the nerve repair and no nerve repair groups. Repair resulted in better s2PD than no repair, but <25% repaired nerves achieved normal levels. Adverse outcomes were similar between repair and no repair groups.

CONCLUSIONS

Only level IV evidence is available to support surgical repair of digital nerves in adults. Return of normal sensibility is uncommon and almost all unrepaired nerves regained protective sensation by 6 months and all patients declined further surgery. There was no difference in adverse outcomes. There is currently a lack of high-quality evidence to support surgical repair of digital nerve injuries in adults and further research is needed.

PROSPERO REGISTRATION NUMBER

CRD42017065092.

Nerve Diameter in the Hand: A Cadaveric Study

Background

Nerve injuries in the hand are common and often pose a challenge for the upper extremity surgeon. A range of reconstructive options exist for nerve repair, but proper matching of nerve diameter is important for many of these techniques. The purposes of this study were to (1) describe the nerve diameters of the hand and their relative differences and (2) investigate whether there is a relationship between nerve diameter and external hand dimensions or body mass index.

Methods

We utilized 18 freshly frozen cadaveric hands from adult donors aged 20-86 of both sexes for this study. Two independent observers measured each nerve diameter to the nearest 0.1 mm using a digital caliper.

Results

Using the flexor zones as boundaries, a total of 33 nerve measurements were performed for each cadaveric hand. Nerve diameter increased from the distal to the proximal flexor zones. The internal common digital nerves in flexor zone 3 were larger than the external digital nerves. The median nerve was found to be nearly 2 times larger than the ulnar nerve at 2 locations within the wrist. There was a positive correlation between body mass index, hand span, hand width, and nerve diameter at several measured locations.

Conclusions

This study provides reference values for nerve diameters of the hand and wrist and describes their relative differences. It is important for surgeons to be aware of these differences and to consider this information as we advance our efforts to reconstruct the hand and develop technologies for nerve repair.

Spatiotemporal microRNA profile in peripheral nerve regeneration: miR-138 targets vimentin and inhibits Schwann cell migration and proliferation

While the peripheral nervous system has regenerative ability, restoration of sufficient function remains a challenge. Vimentin has been shown to be localized in axonal growth fronts and associated with nerve regeneration, including myelination, neuroplasticity, kinase signaling in nerve axoplasm, and cell migration; however, the mechanisms regulating its expression within Schwann cell (SC) remain unexplored. The aim of this study was to profile the spatial and temporal expression profile of microRNA (miRNA) in a regenerating rat sciatic nerve after transection, and explore the potential role of miR-138-5p targeting vimentin in SC proliferation and migration. A rat sciatic nerve transection model, utilizing a polyethylene nerve guide, was used to investigate miRNA expression at 7, 14, 30, 60, and 90 days during nerve regeneration. Relative levels of miRNA expression were determined using microarray analysis and subsequently validated with quantitative real-time polymerase chain reaction. In vitro assays were conducted with cultured Schwann cells transfected with miRNA mimics and assessed for migratory and proliferative potential. The top seven dysregulated miRNAs reported in this study have been implicated in cell migration elsewhere, and GO and KEGG analyses predicted activities essential to wound healing. Transfection of one of these, miRNA-138-5p, into SCs reduced cell migration and proliferation. miR-138-5p has been shown to directly target vimentin in cancer cells, and the luciferase assay performed here in rat Schwann cells confirmed it. These results detail a role of miR-138-5p in rat peripheral nerve regeneration and expand on reports of it as an important regulator in the peripheral nervous system.

Burden of Hand Maladies in US Emergency Departments

BACKGROUND

Hand conditions commonly present to the emergency department (ED), yet data are lacking regarding the magnitude of hand-related conditions in the emergency setting. The purpose of this study is to describe the burden and quantify the health care resource utilization of hand conditions seen in EDs across the United States.

METHODS

Using the National Emergency Department Sample, we identified all ED encounters by patients at least 18 years of age that were associated with a hand condition in 2009 to 2012. The primary outcomes were prevalence, etiology, and associated health care charges for specific categories of hand conditions.

RESULTS

The final sample included 34.4 million ED encounters associated with a common hand condition generating $180.4 billion in health care charges. The volume of hand-related presentations varied in a predictable and cyclical manner, peaking in July and waning in December of each year. Trauma was the most common etiology (77.5%) predominantly due to falls (26.2%) and lacerations (19.7%). Over 4 years, the volume of ED encounters rose (5% increase, P < .001) and as did the resulting health care charges (24.6% increase, P < .001).

CONCLUSIONS

Our study confirms that hand-related conditions contribute significantly to ED volume and consume a growing quantity of health care resources in the United States. The volume of patients presenting to EDs with hand-related conditions fluctuates cyclically throughout the year. Open wounds are the most common cause of presentation and mostly occur in young adults, followed by joint pain, contusions, and fractures.

Age does not affect the outcome after digital nerve repair in children - A retrospective long term follow up

BACKGROUND

Digital nerve injuries in children are not common, but they are considered to have an excellent prognosis, compared to adults, after nerve injury and repair. In studies including both children and adults age have been found to have an effect on outcome after nerve repair.

METHODS

We investigated in a retrospective follow up study the long-time result after digital nerve injury and repair in children, 1-16 years of age (n = 38), and evaluate if age influences outcome. A group with young children, 1-10 years of age (n = 18), was compared with a group with older children, 11-16 years of age (n = 20). A clinical evaluation to evaluate sensation and grip strength was performed and questionnaires were used [Disability of the Arm, Shoulder and Hand (DASH), Cold Sensitivity Severity Scale (CISS), VAS-function and VAS-cosmetic] in median 40 months (range 12-131 months) after the injury and repair.

RESULTS

All patient regained normal sensation. No correlations between age and monofilaments were found. Twenty children (52%) reported some problems with cold intolerance (i.e. CISS), but no other abnormal disability was found (i.e. DASH, VAS); again with no differences between the two groups.

CONCLUSIONS

Children have an excellent long-term recovery after a digital nerve repair and without any influence of age.

Nerve injuries of the upper extremity and hand

A nerve injury has a profound impact on the patient’s daily life due to the impaired sensory and motor function, impaired dexterity, sensitivity to cold as well as eventual pain problems.

To perform an appropriate treatment of nerve injuries, a correct diagnosis must be made, where the injury is properly classified, leading to an optimal surgical approach and technique, where timing of surgery is also important for the outcome.

Knowledge about the nerve regeneration process, where delicate processes occur in neurons, non-neuronal cells (i.e. Schwann cells) and other cells in the peripheral as well as the central nervous systems, is crucial for the treating surgeon.

The surgical decision to perform nerve repair and/or reconstruction depends on the type of injury, the condition of the wound as well as the vascularity of the wound.

To reconnect injured nerve ends, various techniques can be used, which include both epineurial and fascicular nerve repair, and if a nerve defect is caused by the injury, a nerve reconstruction procedure has to be performed, including bridging the defect using nerve-grafts or nerve transfer techniques.

The patients must be evaluated properly and regularly after the surgical procedure and appropriate rehabilitation programmes are useful to improve the final outcome.

Cite this article: EFORT Open Rev 2017;2. DOI: 10.1302/2058-5241.2.160071. Originally published online at www.efortopenreviews.org

Magnetic Resonance Imaging of the Digital Nerves of the Hand: Anatomy and Spectrum of Pathology

Digital nerves are intrinsic to the sensory and motor function of the hand. These nerves represent the terminal ramifications of the ulnar, median, and radial nerves and are located distal to the carpal tunnel and Guyon canal. With magnetic resonance imaging, traumatic and nontraumatic abnormalities of the digital nerves can be shown with high contrast as well as high spatial resolution. Digital nerve abnormalities are most commonly posttraumatic in nature; however, infection, inflammatory, vascular malformations, and neoplasms can rarely occur. Magnetic resonance imaging is playing an increasing role in the assessment of peripheral nerve injury throughout the body, and in the hand, which can accurately identify the extent and character of digital nerve abnormalities before operative intervention.

Predictors of Disability and Quality of Life With an Upper-Extremity Peripheral Nerve Disorder

OBJECTIVE

We sought to understand the wide range of problems that patients with upper-extremity peripheral nerve disorders experience and to identify predictors of disability and quality of life (QOL).

METHOD

Data from standardized assessments of disability and QOL, physical examination results, and intake surveys from 627 patients were analyzed using descriptive and inferential statistics. We compared results between groups and built multivariate models measuring disability, work disability, and physical and mental QOL.

RESULTS

The sample demonstrated substantial disability and even greater work disability, which both closely correlated with poorer QOL. Work status was integral in predicting disability. Common predictors across models included problems with sleep and intimate relationships, deficits in work and household performance, and higher pain.

CONCLUSION

To decrease disability and improve QOL, occupational therapy practitioners should help patients with upper-extremity peripheral nerve disorders identify strategies to maintain meaningful work and household roles, intimate relationships, and sleep, while continuing to address pain.

Direct, indirect and intangible costs of acute hand and wrist injuries: A systematic review

BACKGROUND

Injuries sustained to the hand and wrist are common, accounting for 20% of all emergency presentations. The economic burden of these injuries, comprised of direct (medical expenses incurred), indirect (value of lost productivity) and intangible costs, can be extensive and rise sharply with the increase of severity.

OBJECTIVE

This paper systematically reviews cost-of-illness studies and health economic evaluations of acute hand and wrist injuries with a particular focus on direct, indirect and intangible costs. It aims to provide economic cost estimates of burden and discuss the cost components used in international literature.

MATERIALS AND METHODS

A search of cost-of-illness studies and health economic evaluations of acute hand and wrist injuries in various databases was conducted. Data extracted for each included study were: design, population, intervention, and estimates and measurement methodologies of direct, indirect and intangible costs. Reported costs were converted into US-dollars using historical exchange rates and then adjusted into 2015 US-dollars using an inflation calculator RESULTS: The search yielded 764 studies, of which 21 met the inclusion criteria. Twelve studies were cost-of-illness studies, and seven were health economic evaluations. The methodology used to derive direct, indirect and intangible costs differed markedly across all studies. Indirect costs represented a large portion of total cost in both cost-of-illness studies [64.5% (IQR 50.75-88.25)] and health economic evaluations [68% (IQR 49.25-73.5)]. The median total cost per case of all injury types was US$6951 (IQR $3357-$22,274) for cost-of-illness studies and US$8297 (IQR $3858-$33,939) for health economic evaluations. Few studies reported intangible cost data associated with acute hand and wrist injuries.

CONCLUSIONS

Several studies have attempted to estimate the direct, indirect and intangible costs associated with acute hand and wrist injuries in various countries using heterogeneous methodologies. Estimates of the economic costs of different acute hand and wrist injuries varied greatly depending on the study methodology, however, by any standards, these injuries should be considered a substantial burden on the individual and society. Further research using standardised methodologies could provide guidance to relevant policy makers on how to best distribute limited resources by identifying the major disorders and exposures resulting in the largest burden.

Resistance of primary microsurgical repair of palmar digital nerves to finger mobilization: A cadaver study

The aim of this study was to assess the resistance of microsurgically repaired proper palmar digital nerves (PPDN) to mobilization. Thirty-nine PPDN from fresh forearms cadavers were transected and then sutured using 10/0 nylon. After skin closure, each finger was forcefully flexed and extended 10 times. Out of the 39 repaired nerves, two were elongated and four were ruptured; this amounts to a 15.38% complication rate. We recommend immobilization of nerve repairs, although this contradicts most recent studies.

Does crossover innervation really affect the clinical outcome? A comparison of outcome between unilateral and bilateral digital nerve repair

Digital nerve injuries are the mostly detected nerve injury in the upper extremity. However, since the clinical phenomenon of crossover innervation at some degree from uninjured digital nerve to the injured side occurs after digital nerve injuries is sustained, one could argue that this concept might even result in the overestimation of the outcome of the digital nerve repair. With this knowledge in mind, this study aimed to present novel, pure, focused and valuable clinical data by comparing the outcomes of bilateral and unilateral digital nerve repair. A retrospective review of 28 fingers with unilateral or bilateral digital nerve repair using end-to-end technique in 19 patients within 2 years was performed. Weber's two-point discrimination, sharp/dull discrimination, warm/cold sensation and Visual Analog Scale scoring were measured at final 12-month follow ups in all patients. There was no significant difference in recovery of sensibility after unilateral and bilateral digital nerve repairs. Though there is crossover innervation microscopically, it is not important in the clinical evaluation period. According to clinical findings from this study, crossover innervations appear to be negligible in the estimation of outcomes of digital neurorrhaphy.

G-CSF prevents caspase 3 activation in Schwann cells after sciatic nerve transection, but does not improve nerve regeneration

Exogenous granulocyte-colony stimulating factor (G-CSF) has emerged as a drug candidate for improving the outcome after peripheral nerve injuries. We raised the question if exogenous G-CSF can improve nerve regeneration following a clinically relevant model - nerve transection and repair - in healthy and diabetic rats. In short-term experiments, distance of axonal regeneration and extent of injury-induced Schwann cell death was quantified by staining for neurofilaments and cleaved caspase 3, respectively, seven days after repair. There was no difference in axonal outgrowth between G-CSF-treated and non-treated rats, regardless if healthy Wistar or diabetic Goto-Kakizaki (GK) rats were examined. However, G-CSF treatment caused a significant 13% decrease of cleaved caspase 3-positive Schwann cells at the lesion site in healthy rats, but only a trend in diabetic rats. In the distal nerve segments of healthy rats a similar trend was observed. In long-term experiments of healthy rats, regeneration outcome was evaluated at 90days after repair by presence of neurofilaments, wet weight of gastrocnemius muscle, and perception of touch (von Frey monofilament testing weekly). The presence of neurofilaments distal to the suture line was similar in G-CSF-treated and non-treated rats. The weight ratio of ipsi-over contralateral gastrocnemius muscles, and perception of touch at any time point, were likewise not affected by G-CSF treatment. In addition, the inflammatory response in short- and long-term experiments was studied by analyzing ED1 stainable macrophages in healthy rats, but in neither case was any attenuation seen at the injury site or distal to it. G-CSF can prevent caspase 3 activation in Schwann cells in the short-term, but does not detectably affect the inflammatory response, nor improve early or late axonal outgrowth or functional recovery.

Inter- and intra-tester reliability of sensibility testing in digital nerve repair

The aim of this study was to investigate the inter- and intra-tester reliability of the static two-point discrimination and Semmes-Weinstein monofilament tests in digital nerve repair. A total of 100 digital nerves from 67 patients were included into the study. An experienced orthopaedic surgeon and a physiotherapist examined the sensory nerve recovery. The reproducibility score of both tests was at a poor level, but the reliability of the Semmes-Weinstein monofilament test was higher than the static two-point discrimination test. These tests should not be used alone in the quantitative monitoring of sensory recovery, but should be interpreted with the clinical findings.Level 3 non-randomized controlled study.