Primary Radial Nerve Lesions in Humerus Shaft Fractures-Revision or Wait and See

Background: This study investigates the surgical state-of-the-art procedure for humeral shaft fractures with primary radial nerve palsy based on its own case series in relation to the current and established literature. Methods: Retrospective review of treated cases between January 2018 and December 2022 describing radial nerve palsy after humerus shaft fractures, radiological fracture classification, intraoperative findings, surgical procedure, patient follow-up and functional outcome. Results: A total of 804 patients (463 women and 341 men) with humerus shaft fractures were identified. A total of 33 patients showed symptomatic lesions of the radial nerve (4.1%). The primary lesion was identified in 17 patients (2.1%). A broad and inhomogeneous distribution of fractures according to the AO classification was found. According to the operative reports, the distraction of the radial nerve was found eleven times, bony interposed three times and soft tissue constricted/compressed three times. In every case the radial nerve was surgically explored, there was no case of complete traumatic nerve transection. Four intramedullary nails and thirteen locking plates were used for osteosynthesis. Complete recovery of nerve function was seen in 12 cases within 1 to 36 months. Three patients still showed mild hypesthesia in the thumb area after 18 months. Two patients were lost during follow-up. Conclusions: With this study, we support the strategy of early nerve exploration and plate osteosynthesis in humeral fractures with primary radial nerve palsy when there is a clear indication for surgical fracture stabilisation. In addition, early exploration appears sensible in the case of palsies in open fractures and secondary palsy following surgery without nerve exposure as well as in the case of diagnostically recognisable nerve damage. Late nerve exploration is recommended if there are no definite signs of recovery after 6 months. An initial wait-and-see strategy with clinical observation seems reasonable for primary radial nerve palsies without indication for surgical fracture stabilisation.

Clinical and neurophysiological recovery of ulnar nerve conduction block at the elbow

INTRODUCTION/AIMS

An important mechanism of peripheral nerve motor and sensory dysfunction is conduction block (CB). However, recovery from mechanically induced CB has been rarely studied in humans. The aim of this study was to describe clinical, electrodiagnostic (EDx), and ultrasonographic (US) characteristics of CB recovery in ulnar neuropathy at the elbow (UNE).

METHODS

We recruited a group of consecutive patients presenting to our EDx laboratory with UNE and >50% motor CB. Patients' histories were obtained and neurologic, EDx, and US examinations were repeated every 1-3 mo for at least 12 mo.

RESULTS

We studied 10 patients (5 men), with a mean age of 63 y (range, 51-81 y). In all affected arms CB was localized to the retrocondylar groove. Following conservative management, myometrically measured index finger abduction improved from a median of 49% to 100% relative to the contralateral index finger, and ulnar nerve CB decreased from a median of 74% to 6%. Most of the improvement took place within 8 mo of symptom onset, and 6 mo after receiving treatment instructions. Mean motor nerve conduction velocity improved from 15 to 27 m/s in the most affected 2-cm ulnar nerve segment.

DISCUSSION

The resolution of CB after typical chronic compression may take longer than after acute compression. This should be considered by clinicians when estimating prognosis for discussions with patients.

Effects of platelet-rich fibrin and dexamethasone on nerve regeneration after acute facial-nerve injury

BACKGROUND

Acute facial-nerve injury.

OBJECTIVE

To investigate the effects of platelet-rich fibrin (PRF) and dexamethasone on nerve regeneration.

MATERIALS AND METHODS

Thirty-six rats were randomly divided into six groups. Facial-nerve injury was created using a full-thickness incision in all groups except Group E. Next, primary anastomosis, PRF application, topical dexamethasone application, primary anastomosis with topical PRF and dexamethasone application, and no facial-nerve repair were performed in Groups A, B, C, D, and F, respectively. Clinical, functional, and structural improvements were evaluated at eight weeks.

RESULTS

The mean eye-closure movement score in Group B was significantly higher than that in Group F (p < .001). The mean whisker-movement score in Group B was significantly higher than that in Group F (p = .001). The mean amplitude of whisker movement in Group F was significantly lower than those in Groups A, B, C, and E, and the mean amplitude in Group D was significantly lower than that in Group E (p < .001). Furthermore, an improvement in nerve ultrastructure was observed in Group B.

CONCLUSION

PRF application has a positive effect on nerve recovery after anastomosis.

SIGNIFICANCE

Contribute to the literature to improve nerve regeneration.

Longitudinal traumatic peripheral nerve injury recovery: quantitative description, classification and prediction

Aim: Repair of peripheral nerves is recommended following transection. Systematic evaluation of longitudinal recovery in injury models is needed to improve patient management. Gompertz function provided straightforward interpretation and prediction of recovery outcomes. Materials & methods: Behavioural sciatic function index, measured 3 days post injury, and weekly for 12 weeks following full nerve transection and repair (n = 6) as well as crush injuries (n = 6). Results: Gompertz parametrization provided early classification between types of traumatic peripheral nerve injuries following surgical repair. Results distinguished injury nerves (A: p < 0.01; T_i: p < 0.05; Ic: p < 0.05 and outcome: p < 0.01). Early prognostication of outcomes (crush: 5.5 ± 0.3 and cut/repair: 8 ± 1 weeks) preceded current methods. Conclusion: Our findings identify injury type, state of recovery and early prognostication of outcome.

Effects of subepineural hyaluronic acid injection on nerve recovery in a rat sciatic nerve defect model

BACKGROUND

Maintenance of epineural integrity is very important for nerve healing. Reports on the use of substances consid-ered to have positive effects on nerve healing in experimental nerve defect models are increasing. The present study assessed the effects of sub-epineural hyaluronic acid injection in a rat sciatic nerve defect model that was created while maintaining epineural integrity.

METHODS

The study included 40 Sprague Dawley rats. The rats were randomly divided into a control group and three experimental groups (10 rats in each group). In the control group, the sciatic nerve was dissected and no additional surgery was performed. In experimental group 1, the sciatic nerve was transected in the middle, and then, primary repair was performed. In experimental group 2, a 1-cm defect was created while preserving the epineurium, and then, the defect was repaired with end-to-end suturing of the pre-served epineurium. In experimental group 3, the surgical procedure for experimental group 2 was performed, and then, sub-epineural hyaluronic acid injection was carried out. Functional and histological evaluations were performed.

RESULTS

On functional evaluation, there was no statistically significant difference among the groups during the 12-week follow-up period. On histological evaluation, nerve recovery was poorer in experimental group 2 than in experimental groups 1 and 3 (p<0.05).

CONCLUSION

Although the functional analysis did not reveal any significant results, the histological findings suggest that hyaluronic acid increases the regeneration capacity of axons through its anti-fibrotic and anti-inflammatory effects.

Patient-Reported Outcomes and Provocative Testing in Peripheral Nerve Injury and Recovery

Background  Peripheral nerve function is often difficult to assess given the highly variable presentation and subjective patient experience of nerve injury. If nerve assessment is incomplete or inaccurate, inappropriate diagnosis and subsequent treatment may result in permanent dysfunction. Objective  As our understanding of nerve repair and generation evolves, so have tools for evaluating peripheral nerve function, recovery, and nerve-related impact on the quality of life. Provocative testing is often used in the clinic to identify peripheral nerve dysfunction. Patient-reported outcome forms provide insights regarding the effect of nerve dysfunction on daily activities and quality of life. Methods  We performed a review of the literature using a comprehensive combination of keywords and search algorithms to determine the clinical utility of different provocative tests and patient-reported outcomes measures in a variety of contexts, both pre- and postoperatively. Results  This review may serve as a valuable resource for surgeons determining the appropriate provocative testing tools and patient-reported outcomes forms to monitor nerve function both pre- and postoperatively. Conclusion  As treatments for peripheral nerve injury and dysfunction continue to improve, identifying the most appropriate measures of success may ultimately lead to improved patient outcomes.

Patterns of Nerve Injury and Recovery Rates of Infraclavicular Brachial Plexus Lesions Following Anterior Shoulder Dislocation

PURPOSE

We reviewed our cases of infraclavicular brachial plexus injuries associated with anterior shoulder dislocation to determine patterns of injury, recovery rates, and factors associated with a poor motor outcome.

METHODS

This was a retrospective review of patients who had sustained a concomitant nerve injury following dislocation of the glenohumeral joint treated with closed manipulation. The data collected included patient demographics, injury factors, and patterns of neurological deficits. The Medical Research Council (MRC) grade for motor power was the primary outcome measure, where a grade of 4 or 5 was regarded as achieving good motor recovery. Univariate and multivariable analyses were used to identify factors associated with persistent motor weakness (MRC grades 0-3) at the final follow-up.

RESULTS

Between 2015 and 2019, 61 patients were assessed. There were 36 males and 25 females, with a median age of 64 years (interquartile range [IQR], 53-73 years). Four patterns of injury were identified: (1) isolated axillary nerve lesions; (2) single cord lesions; (3) combined lesions involving the medial and posterior cords; and (4) diffuse lesions affecting all 3 cords. Of 28 patients with isolated axillary nerve injuries, 22 recovered. All lateral cord injuries (11/11) and 20 of 24 posterior cord injuries recovered spontaneously. Recovery of hand intrinsic function from medial cord injuries had the worst outcome, with 14 of 27 patients not recovering beyond MRC grades 0 to 3. The median duration of dislocation before reduction was 6 hours (IQR, 3-12 hours). A multivariate analysis showed an association between the duration of shoulder dislocation and the likelihood of persistent motor weakness.

CONCLUSIONS

Shoulder dislocations with motor deficits should be regarded as orthopedic emergencies and reduced expediently. Persistent motor weakness may be associated with a prolonged duration of dislocation prior to glenohumeral relocation.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Peripheral Nerve Injury Treatments and Advances: One Health Perspective

Peripheral nerve injuries (PNI) can have several etiologies, such as trauma and iatrogenic interventions, that can lead to the loss of structure and/or function impairment. These changes can cause partial or complete loss of motor and sensory functions, physical disability, and neuropathic pain, which in turn can affect the quality of life. This review aims to revisit the concepts associated with the PNI and the anatomy of the peripheral nerve is detailed to explain the different types of injury. Then, some of the available therapeutic strategies are explained, including surgical methods, pharmacological therapies, and the use of cell-based therapies alone or in combination with biomaterials in the form of tube guides. Nevertheless, even with the various available treatments, it is difficult to achieve a perfect outcome with complete functional recovery. This review aims to enhance the importance of new therapies, especially in severe lesions, to overcome limitations and achieve better outcomes. The urge for new approaches and the understanding of the different methods to evaluate nerve regeneration is fundamental from a One Health perspective. In vitro models followed by in vivo models are very important to be able to translate the achievements to human medicine.

Predictors of traumatic nerve injury and nerve recovery following humeral shaft fracture

INTRODUCTION

Nerve palsy is common after humeral shaft fracture, with the radial nerve being the most commonly injured nerve. Isolated nerve injuries usually recover spontaneously, and operative intervention is rarely indicated. Our goal was to study the predictors of traumatic nerve injury and recovery in a large cohort of patients with humeral shaft fractures.

METHODS

A total of 376 patients with humeral shaft fracture, including 96 patients with documented traumatic nerve palsy and 280 with intact neurovascular examination on presentation, were retrospectively included in the study. The primary outcome was incidence of a traumatic nerve palsy, and the secondary outcome was nerve recovery.

RESULTS

Nerve palsy was present in 96 patients (25.5%) at the time of injury. Radial nerve was the most commonly injured nerve (93.6%), followed by the ulnar (5.1%) and axillary (1.2%) nerves. Seventeen patients (17.7%) had multiple nerves palsies. A multivariable regression analysis revealed that the concomitant vascular injury (odds ratio [OR] 52, 95% confidence interval [CI] 5.6-480.6), distal one-third fractures (OR 6.3, 95% CI 2.7-14.7), and middle one-third (OR 2.8, 95% CI 1.2-6.5) vs. proximal fractures, open fracture (OR 2.1, 95% CI 1.1-4.4), and high-energy trauma (OR 1.7, 95% CI 1.1-2.9) were independent predictors of nerve palsy. Iatrogenic nerve injury was detected in 7 patients (4.6%), all affecting the radial nerve. Spontaneous recovery of traumatic nerve injuries was detected in 87 patients (91%), with 19% partial and 72% complete recovery. The initial sign of recovery was observed at median times of 7 and 9 weeks for those managed conservatively or fracture fixation. Operative treatment of the fracture had no effect on the outcome of nerve recovery (88.5% vs. 100%, P = .14). Ten patients (14.1%) had transected nerves at the time of exploration and open fractures (22.7% vs. 6.8%, P = .04), and concomitant vascular injury (33.3% vs. 7.3%, P = .02) were associated with nerve transection, portending a worse prognosis for nerve recovery compared with nerves in continuity (40% vs. 95.3%, P = .004).

DISCUSSION

The incidence of nerve injury after humeral shaft fracture was 25%, reflecting an abundance of high-energy and open injuries in this cohort. Ninety-one percent of patients experienced improvement in their nerve function with a median time to recovery of 7-9 weeks. Operative treatment of the fracture did not change the rate of nerve recovery. Patients with multiple nerve palsies and concurrent vascular insult had worse nerve recovery. We recommend nerve studies if no sign of recovery is observed by 9 weeks.

Optimal E2 (reference) electrode placement in fibular motor nerve conduction studies recording from the tibialis anterior muscle

INTRODUCTION

In this study we aimed to determine the contribution of the E2 (reference electrode) to the compound muscle action potential (CMAP) amplitude during fibular motor recording to the tibialis anterior (TA) when E2 is placed over routine referential vs. alternative sites.

METHODS

The CMAP was obtained from 10 healthy subjects, using the active electrode (E1) over sites routinely used as E2 for the TA, whereas the E2 was over the contralateral knee. The same procedure was performed with the E1 over alternative E2 sites.

RESULTS

Significant electrical signal was captured over routine E2 placement sites. Among the tested alternative E2 sites, the ipsilateral patella (especially its medial aspect) was the most electrically silent.

DISCUSSION

Using alternative E2 sites with near isoelectric recordings can optimize near-field potential measurement in the fibular motor recording to the TA and represents a more accurate way of measuring nerve and muscle function. Muscle Nerve 59:249-253, 2019.

Electrodiagnostic evidence of suprascapular nerve recovery after decompression

INTRODUCTION

The purpose of this study was to determine whether surgical arthroscopic decompression or ultrasound-guided aspiration of a paralabral cyst would result in suprascapular nerve recovery from axonal regeneration based on electrodiagnostic testing.

METHODS

Nine patients with preoperative electromyography (EMG) evidence of suprascapular neuropathy due to paralabral cysts at the suprascapular or spinoglenoid notch were prospectively studied. Eight patients underwent arthroscopic surgical decompression, and 1 patient underwent ultrasound-guided aspiration. Postoperative EMG was performed in all patients to evaluate nerve regeneration.

RESULTS

Three (33%) patients had cysts at the suprascapular notch, whereas 6 (67%) patients had cysts at the spinoglenoid notch. All patients showed complete electrophysiological recovery after decompression.

DISCUSSION

Decompression of paralabral cysts at the suprascapular or spinoglenoid notch resulted in postoperative EMG evidence of nerve recovery. Long-term studies with a greater number of patients are required to elucidate time to recovery. Muscle Nerve 59:247-249, 2019.

Neurologic complications of shoulder joint replacement

BACKGROUND

Little attention has been given to neurologic complications after shoulder joint replacement (SJR). Previously thought to occur infrequently, it is likely that many are not clinically recognized, and they can result in postoperative morbidity and impair the patient's recovery. The purpose of this study was to document the prevalence of nerve complications after SJR, to identify the nerves involved, and to define patient outcomes.

METHODS

This was a retrospective review of 211 SJRs in 202 patients during a 5-year period were included, with 89 male and 122 female patients at an average age of 70 years. All patients underwent a comprehensive analysis of any postoperative nerve complication, including onset, duration, investigation, treatment, and symptom resolution.

RESULTS

Of the 211 SJR procedures, 44 were identified as having sustained a nerve complication (20.9%), with 36 female (81.8%) and 8 male patients (18.2%). Reverse SJR was associated with the highest number of nerve complications. The median nerve (25 patients) and musculocutaneous nerve (8 patients) were most commonly involved. Most nerve complications were transient and resolved within 6 months. Permanent sequelae and injuries that required secondary surgical intervention were rare.

CONCLUSION

The occurrence of nerve complications after SJR is common, but almost all will fully recover. Most are transient neurapraxias involving the lateral cord of the brachial plexus. Women are more likely to be affected, as are patients who have undergone prior surgery to the affected shoulder. Most are likely to be the result of excessive traction or direct injury to the nerves during glenoid exposure.

Recovery of mechanical detection thresholds after direct digital nerve repair versus conduit implantation

The purpose of this study was to assess sensory and functional nerve recovery after digital nerve injury in patients with an end-to-end suture (S) or with implantation of a collagen conduit (C) to bridge a nerve gap. Fifteen S and 11 C with a follow-up of 6-36 months and 28 healthy control participants were enrolled. Methods of assessments were quantitative sensory testing, the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH), range of motion and the painDetect questionnaire. After both procedures, sensory profiles showed largely recovered function of C and Aδ fibres but severe loss of Aβ-fibre function leading to increased mechanical detection thresholds. There was only minimal allodynia. Severe pain was absent. Patients with conduits reported more functional impairment, especially in work performance, which correlated with the assessed loss of Aß-fibre function.

LEVEL OF EVIDENCE

III.