Radial Nerve Palsy After Humeral Shaft Fractures: The Case for Early Exploration and a New Classification to Guide Treatment and Prognosis

Results of Tendon Transfers in Radial Nerve Palsies: A New Evaluation Protocol

Radial nerve palsies present a challenging clinical scenario, often leading to substantial functional impairment. This study focuses on evaluating the outcomes of tendon transfer surgeries in patients with post-traumatic radial nerve injuries. The radial nerve, vital for upper limb movements, faces various etiologies, such as trauma, compression, or idiopathy. Patients with radial nerve palsy encounter difficulties in daily activities, emphasizing the need for effective management strategies. The research introduces a novel evaluation protocol, aiming to comprehensively assess tendon transfer outcomes. This protocol incorporates functional movements of wrist and finger joints, encompassing both objective and subjective parameters. The retrospective study includes eleven patients treated between 2010 and 2022, with a minimum follow-up of one year post-surgery. Tendon transfers demonstrated positive results. The evaluation protocol covers a wide range of parameters, including wrist and finger mobility, thumb function, grip strength, and patient satisfaction. The results indicate successful restoration of motor function, with an average grip strength of 70% compared to the healthy arm. The proposed evaluation protocol facilitates standardized and reproducible assessment, minimizing subjective errors in clinical evaluations. Despite the study's limitations, such as a relatively small sample size, the findings underscore the effectiveness of tendon transfers in treating radial nerve palsies. The introduced evaluation scheme provides a comprehensive and reproducible approach to assess outcomes, contributing to the global standardization of tendon transfer assessments in radial nerve injuries.

Enhanced nerve function recovery in radial nerve palsy patients with humerus shaft fracture: a randomized study of low-frequency pulse electrical stimulation combined with exercise therapy

Objective

To evaluate the effect of low-frequency pulse electrical stimulation plus exercise therapy on nerve function recovery in patients with radial nerve palsy after humerus shaft fracture.

Methods

A total of 110 patients with humerus shaft fracture and radial nerve injury admitted to our hospital from January 2017 to December 2021 were recruited. They were randomized to receive either conventional exercise therapy (control group) or conventional exercise therapy plus low-frequency pulse electrical stimulation (study group) according to the random number table method, with 55 cases in each. Clinical efficacy, muscle strength recovery, nerve conduction velocity (MCV), amplitude, wrist joint, and elbow joint activities of patients were analyzed and compared.

Results

Patients with low frequency stimulation (LFS) showed significantly higher treatment effectiveness (89.09%) than those with exercise therapy only (69.09%). The incorporation of LFS with exercise therapy provided more enhancement in the muscle strength of wrist extensor and total finger extensor in patients when compared with a mere exercise intervention, suggesting better muscle function recovery of patients produced by LFS. Moreover, a significant increase in MCV and its amplitude was observed in all included patients, among which those receiving LFS showed a greater escalation of MCV and its amplitude. Following a treatment duration of 6 months, more patients in the LFS cohort were reported to achieve a wrist extension and elbow extension with an angle over 45° than the controls. There was no notable variance in adverse responses noted between the two patient groups.

Conclusion

In patients afflicted with humerus shaft fracture and radial nerve injury, the amalgamation of exercise therapy with low-frequency pulse electrical stimulation can significantly improve clinical efficacy, promote nerve function, and muscle strength recovery, and features a high safety profile.

Relevance to clinical practice

The combination of exercise therapy and low-frequency pulsed electrical stimulation can notably improve the promotion of neurologic function and muscle strength recovery in patients with humerus shaft fractures and radial nerve injuries with a high degree of safety.Clinical trial registration:https://www.researchregistry.com, identifier researchregistry9461.

Radial Nerve Palsy in the Setting of Humeral Shaft Fracture

The upper limb has a complex anatomy comprised of many nerve and vascular structures, making humeral shaft fractures extremely important. Injury to the humeral shaft commonly occurs due to trauma and affects younger male or older female patients. The radial nerve travels along the spiral groove of the humerus, placing it at an increased risk of damage in humeral shaft fractures. If injured, there are a variety of classifications of radial nerve injury, different indications for exploration, and treatment methods that orthopedic surgeons have available in treating these injuries. This review aims to discuss the etiology of humeral shaft fracture-associated radial nerve palsy, tools for diagnosis, and treatment.

Two fingerbreadths, one finger's width: on the proximity of the radial nerve to the deltoid tuberosity

INTRODUCTION

The aim of this study was to find a convenient technique to evaluate the location of the radial nerve (RN) with reference to the deltoid tuberosity (DT).

MATERIALS AND METHODS

Sixty-eight upper extremities, embalmed using a modified version of Thiel's method, were included in the study. The interval between the tip of the greater tubercle of the humerus and the distal tip of the lateral humeral epicondyle (LE) was defined as humeral length (HL). The most prominent point of the DT was used as the point of reference. Through this point, a horizontal reference line which met the humeral axis at the dorsal side of the humeral shaft was simulated. The longitudinal distance between the crossing point of the horizontal line and the humeral axis and the RN was measured (distance 1). The interval between the intersection point and the reference point at the DT was measured (distance 2). Data were evaluated in centimeters.

RESULTS

For the whole sample, the HL averaged 31.0 cm (SD: 2.3; range 26.2-36.9). Distance 1 averaged 2.2 cm (SD: 0.3; range 1.6-3.1), and distance 2 averaged 1.2 cm (SD: 1.0; range 0-2.8). The HL was larger in the male group when compared to females (p < 0.001; males mean: 32.2 cm; females mean 29.5 cm). There was no difference regarding distance 2 (p = 0.59; males mean: 1.2 cm; females mean: 1.3 cm) between the sexes. Distance 1 was significantly (p = 0.02) larger in the male group (mean: 2.3 cm) when compared to females (mean: 2.1 cm). Concerning sides, there were no differences regarding all evaluated parameters (HL: p = 0.6; Distance 1: p = 0.6; distance 2: p = 0.8).

CONCLUSIONS

This study provides an easily applicable technique to localize the RN with reference to the DT.

VARIATIONS OF THE STRUCTURE, TOPOGRAPHY, BLOOD SUPPLY AND INNERVATION OF THE BRACHIORADIALIS IN HUMAN FETUS

OBJECTIVE

The aim of the research was to establish the features of age-related and individual anatomical variability of the brachioradialis, its blood supply, and innervation options.

PATIENTS AND METHODS

Materials and methods: The study of the variant anatomy of the brachioradialis and its vascular and nervous structures was carried out on 25 preparations of human fetuses of 4-7 months, 81.0-270.0 mm parietal-coccygeal length (PCL) using macromicroscopic preparation, injection vessels, and morphometry.

RESULTS

Results: Spindle-like (56%) and round (24%) shapes of the brachioradialis were found in most of the studied fetuses; its elongated flat (12%) and triangular (8%) forms occur less often. In a fetus of 185.0 mm TKD, the right brachioradialis consisted of two separate parts: upper and lower, which were connected at the level of the middle of the forearm into a common short muscle belly. In another human fetus of 220.0 mm TKD, the right brachioradialis also consisted of two separate parts - upper and lower, triangular in shape, but separated by a pronounced horizontal gap.

CONCLUSION

Conclusions: The features of the fetal anatomy of the brachioradialis are established: its variability and bilateral asymmetry of shape and size, variability of the places of origin and attachment, etc. In individual human fetuses, the brachioradialis consists of two separate parts that have special topographical relationships. The area of the greatest concentration of both extra- and intramuscular nerves and arteries is the upper and middle third of the brachioradialis. In the area of the forearm, the course of radial vascular-nerve formations is determined by the brachioradialis.

Risk of Radial Nerve Injury in Anterolateral Humeral Shaft Plating

PURPOSE

The purpose of this study was to evaluate and compare the risk of iatrogenic radial nerve injury between arm positionings of 45° and 60° abduction in anterolateral humeral plating using a 4.5-mm narrow dynamic compression plate.

METHODS

Fifty-six humeri of cadavers in the supine position with 45° of arm abduction were exposed through the anterolateral approach. A hypothetical fracture line was marked at the middle of the humerus, and a precontoured ten-hole 4.5-mm narrow dynamic compression plate was applied and fixed to the anterolateral surface. After the fixation, the radial nerve was exposed through a triceps-splitting approach. Screws in contact with or which had penetrated the radial nerve were deemed to be injuries. Then, the screws and plate were removed, the arm changed to the 60° arm abduction position, and the steps of applying the plate and inserting the screws were followed as in the 45° arm abduction step.

RESULTS

The screws which could potentially injure the radial nerve were those of the second to sixth screw holes in both the 45° and 60° of arm abduction positions. The incidences of iatrogenic radial nerve injury of the second to sixth screw holes in the 45° position were 5.36%, 39.29%, 80.36%, 60.71%, and 10.71%, respectively, and at the 60° position were 5.36%, 53.57%, 83.93%, 60.71%, and 7.14%, respectively. There were no statistically significant differences in risk of injury between the two positions in all screw holes (all P-values > 0.05).

DISCUSSION

In anterolateral humeral shaft fixation, arm abduction position did not affect the risk of iatrogenic radial nerve injury, with the main risk from certain screw holes. The surgeon should be careful in screw insertion, especially at the fourth and fifth screw holes.

LEVEL OF EVIDENCE

IV; cadaveric study.

Radial Nerve Paralysis in Diaphyseal Fractures of the Humerus

One of the most common complications associated with a diaphyseal humeral fracture is the development of a radial nerve injury. We conducted a study to analyze the degree of recovery and prognostic factors associated with radial nerve palsy in patients with diaphyseal humerus fractures. We retrospectively analyzed 28 patients who presented to the Hospital La Fe, Valencia, Spain, with a diaphyseal humerus fracture associated with radial nerve injury between 2010 and 2020. A total of 14.3% (n = 4) of the patients in our cohort had open fractures and 85.7% (n = 24) had closed fractures. There were no statistically significant differences between the type of treatment and the type of fracture (p = .13). There were also no significant differences between the type of treatment and recovery time (p = .42). There was a statistically significant difference (p = .04) in the mean recovery time for patients with preoperative radial nerve injuries (11.9 months) compared with patients who sustained a radial nerve injury secondary to surgical repair of the fracture (8.6 months). The difference in recovery time between patients with open and closed fractures was not statistically significant (p = .3). Results of the study showed that the type of fracture (i.e., open or closed) did not affect radial nerve palsy recovery time. Patients who sustain radial nerve injuries secondary to a surgical repair have a shorter recovery time than patients who sustain primary radial nerve injuries.

Humeral Shaft Fractures: A Literature Review on Current Treatment Methods

In this review, we aim to provide a concise yet comprehensive summation of the assessment and management of humeral shaft fractures. These are uncommon but prevalent enough that they are part of any trauma surgeon's scope of practice. They have historically been treated using non-operative methods, including braces and casts, supported by published excellent results in the rate of the bone union. However, recently published studies challenge these results and suggest the outcomes might be better with surgery, but the complications of an operation such as infection and nerve injury can not be overlooked. In summary, non-surgical treatment is still the gold standard in the treatment of these fractures, but the indications for surgical management are now clearer and include early signs of delayed union and patients who are unable to have a brace fitted or are uncompliant. It is likely that these new developments will start to change practice, and therefore the treatment of humeral shaft fractures should be a topic of interest of any clinician who deals with them.

The risk of iatrogenic radial nerve and/or profunda brachii artery injury in anterolateral humeral plating using a 4.5 mm narrow DCP: A cadaveric study

INTRODUCTION

Fixation of humeral shaft fractures with a plate and screws can endanger the neurovascular structure if proper care is not taken. No studies to our knowledge have studied the risk of iatrogenic radial nerve and/or profunda brachii artery (RNPBA) injury from each screw hole of a 4.5 mm narrow dynamic compression plate (narrow DCP). The purpose of this study is to evaluate the risk of RNPBA injury in anterolateral humeral plating with a 4.5 mm narrow DCP.

MATERIAL AND METHODS

18 humeri of 9 fresh-frozen cadavers in the supine position were exposed via the anterolateral approach with 45 degrees of arm abduction. A hypothetical fracture line was marked at the midpoint of each humerus. A precontoured ten-hole 4.5mm narrow DCP was applied to the anterolateral surface of the humerus using the fracture line to position the center of the plate. All screw holes were drilled and screws inserted. The cadaver was then turned over to the prone position with 45 degrees of arm abduction, and the RNPBA exposed. The holes through in which 100% of the screw had contact with or penetrated the RNPBA were identified as dangerous screw holes, while lesser percentages of contact were defined as risky.

RESULTS

The relative distance ratios of the entire humeral length from the lateral epicondyle of the humerus to the 4th, 3rd, 2nd and 1st proximal holes were 0.64, 0.60, 0.56 and 0.52, respectively. The most dangerous screw hole was the 2nd proximal, in which all 18 screws had contacted or penetrated the nerve, followed by the risky 1st (12/18), 3rd (8/18) and 4th (2/18) holes.

CONCLUSION

In humeral shaft plating with the 4.5mm narrow DCP using the anterolateral approach, the 2nd proximal screw hole carries the highest risk of iatrogenic radial nerve and/or profunda brachii artery injury.

[Functional reconstruction in traumatic paralysis]

BACKGROUND

Traumatic nerve injuries are associated with a high morbidity and long rehabilitation times. The extent of a nerve lesion and the related regeneration potential can often only be estimated during the course, whereby the time window for successful surgical interventions is limited.

OBJECTIVE

The incidence and distribution of traumatic nerve lesions are reported. Algorithms for treatment decisions are presented.

MATERIAL AND METHODS

Statistics from the German TraumaRegister DGU® as well as international registers were evaluated. The results of basic research and expert recommendations for diagnostics and treatment are discussed.

RESULTS AND CONCLUSION

A strategic approach to conservative and surgical treatment of traumatic nerve injuries depending on the extent of injury and resulting regeneration potential is recommended. In conjunction with the clinical course, electrophysiology and imaging diagnostics, e.g. nerve sonography, can help to differentiate between neurapraxia, axonotmesis and neurotmesis.

Need for early exploration of radial nerve in humeral shaft fractures with radial nerve palsy

INTRODUCTION

Radial nerve palsy (RNP) associated with humeral shaft fracture (HSF) is the most common nerve complication in long bone fractures. There is still controversy over the need for immediate exploration of the radial nerve (RN) in HSF with RNP. The purpose of the current study was to determine which situations of HSF with RNP require early exploration of the RN.

MATERIALS AND METHODS

This is a retrospective study that included 55 patients who had visited the emergency department of the current authors' hospital and had been diagnosed with HSF between March of 2005 and September of 2015. Of these 55 patients, 14 (25.4%) had been diagnosed with HSF with RNP. We reviewed the medical records of those 14 patients and their radiographs to evaluate each fracture's type, location, pattern, energy of trauma, status of RN injury, and time until recovery from RNP.

RESULT

All the 14 RNP patients had suffered high-energy trauma. Three had fractures in the proximal third (21.4%), six in the middle third (42.9%), and five in the distal third (35.7%). The three patients (21.4%) with incomplete recovery of RNP all had proximal third fractures; two of these three patients had RN transection.

CONCLUSION

Early exploration of the radial nerve should be considered in patients with radial nerve palsy associated with proximal third humeral shaft fracture, regardless of the fracture patterns caused by the high-energy trauma.

Radial nerve palsy following humeral shaft fracture: a theoretical PNF rehabilitation approach for tendon and nerve transfers

Background:Humerus fracture-induced radial nerve injury can create severe and permanent disabilities. Purpose:Surgical management often relies on either tendon or nerve transfer. Regardless of which procedure is selected, physical therapists are challenged to restore functional outcomes without jeopardizing repair healing. Through synergistic, multi planar upper extremity movement patterns, neuromuscular irradiation, or overflow, and neuroplasticity, proprioceptive neuromuscular facilitation (PNF) may improve strength, range of motion and tone. Methods:After reviewing the literature, a five phase PNF-based treatment approach is proposed with timing differences based on the selected procedure. Findings:Phase I (2 or 4 weeks pre-surgery for tendon or nerve transfer, respectively) consists of comprehensive patient education; Phase II (4-6 or 1-2 weeks post-surgery for tendon or nerve transfer, respectively) explores variable duration peripheral and central nervous system motor learning during isometric activation to enhance central neuroplasticity; Phase III (7-12 or 3-20 weeks post-surgery for tendon or nerve transfer, respectively) incorporates low-intensity motor control including contralateral isotonic upper extremity loading to maximize overflow and neuroplastic effects; Phase IV (13-26 or 21-52 weeks post-surgery for tendon or nerve transfer, respectively) adds high-intensity strength and motor control using ipsilateral isotonic upper extremity loading to maximize overflow and neuroplastic effects. Phase V (27-52 or 53-78 weeks post-surgery for tendon or nerve transfer, respectively) progresses to more activity of daily living, vocational, or sport-specific training with higher intensity strength and motor control tasks. Conclusions:Through manually guided synergistic, multi planar movement, overflow, and neuroplasticity, a PNF treatment approach may optimize neuromuscular recovery. Validation strategies to confirm clinical treatment efficacy are discussed.

Surgical anatomy of the radial nerve in the arm: a cadaver study

PURPOSE

The purpose of this study was to analyse the anatomic course of the radial nerve (RN) in the arm, in order to minimize the potential risk of surgical injury.

METHODS

The study was performed in 19 embalmed upper extremities of 11 adult human cadavers. We measured: distance from deltoid insertion (DI) into the humerus to lateral epicondyle (LE); distance from RN piercing point into the lateral intermuscular septum (LIS) to three other points-DI, LE and RN division into superficial and deep terminal branches; distance between the LE and the RN division. To assess variability, we correlated the distances between the landmarks to the overall length of the arm.

RESULTS

The RN was found to pierce the LIS within 31.6 mm of the most distal DI into the humerus. The mean distance between the entry point of RN in the LIS and the LE was 107.2 mm. The mean distance between RN perforating point in the LIS and RN division in its terminal branches was 86.4 mm. The DI-LE and the LIS-LE showed a moderate positive correlation with the length of the arm.

CONCLUSION

We describe the DI relationship to the RN course and also report its proportion within overall arm length which has not been previously described. Using the arm length as reference, our results show that RN can be found to perforate on the LIS at a point distal to the DI by 11% and proximal to the LE by 38%.

Radial nerve palsy associated with closed humeral shaft fractures: a systematic review of 1758 patients

BACKGROUND AND PURPOSE

Humeral shaft fractures are often associated with radial nerve palsy (RNP) (8-16%). The primary aim of this systematic review was to assess the incidence of primary and secondary RNP in closed humeral shaft fractures. The secondary aim was to compare the recovery rate of primary RNP and the incidence of secondary RNP between operative and non-operative treatment.

METHODS

A systematic literature search was performed in 'Trip Database', 'Embase' and 'PubMed' to identify original studies reporting on RNP in closed humeral shaft fractures. The Coleman Methodology Score was used to grade the quality of the studies. The incidence and recovery of RNP, fracture characteristics and treatment characteristics were extracted. Chi-square and Fisher exact tests were used to compare operative versus non-operative treatment.

RESULTS

Forty studies reporting on 1758 patients with closed humeral shaft fractures were included. The incidence of primary RNP was 10%. There was no difference in the recovery rate of primary RNP when comparing operative treatment with radial nerve exploration (98%) versus non-operative treatment (91%) (p = 0.29). The incidence of secondary RNP after operative and non-operative treatment was 4% and 0.4%, respectively (p < 0.01).

INTERPRETATION

One-in-ten patients with a closed humeral shaft fracture has an associated primary RNP, of which > 90% recovers without the need of (re-)intervention. No beneficial effect of early exploration on the recovery of primary RNP could be demonstrated when comparing patients managed non-operatively with those explored early. Patients managed operatively for closed humeral shaft fractures have a higher risk of developing secondary RNP.

LEVEL OF EVIDENCE

Level IV; Systematic Review.

Delayed Radial Nerve Palsy After Nonoperative Treatment of Humeral Shaft Fractures: A Report of 2 Cases

CASE

Two patients who developed radial nerve palsy at least 6 weeks after injury during nonoperative treatment of humeral shaft fractures. This complication was associated with external bracing, progressive varus angulation during treatment, and excess callus formation.

CONCLUSION

Delayed radial nerve palsy may develop during nonoperative treatment of humeral shaft fractures when functional bracing fails to maintain alignment and stability at the fracture site.

Effectiveness of ultrasonographic evaluation under general anesthesia for radial nerve palsy associated with humeral fractures during the first operation

PURPOSE

To evaluate the effectiveness of sonographic evaluation of the radial nerve at the first operation for closed humeral fracture cases.

METHODS

Seventeen cases of closed humeral fractures were included in this study. These cases were categorized into two groups: Group P, consisting of seven cases with complete radial nerve palsy after the injuries; and Group C, consisting of ten cases without radial nerve palsy after the injuries. Sonographic evaluation of the condition of the radial nerve was performed before or after open or closed reduction and internal fixation (ORIF or CRIF) during the first operation.

RESULTS

Five of seven Query ID="Q2" Text=" As keywords are mandatory for this journal, please provide 3-6 keywords." cases in Group P showed entrapment or compression of the radial nerve at fracture sites with sonography. Simultaneous radial nerve exploration (SRNE) confirmed sonographic findings in these five cases. The other two cases showed no abnormal sonographic findings except swelling of the radial nerve. CLIF without SRNE was selected and additional sonographic reevaluation of the nerve after CRIF confirmed there were no iatrogenic nerve injuries in these two cases. All of the ten cases in Group C showed no abnormal sonographic findings of the radial nerve. Five of these ten cases selected ORIF, exposed the nerve at the time of approaching the fracture site, and matched sonographic findings. The other five cases without exposure of the nerve confirmed no iatrogenic radial nerve injuries with additional sonographic reevaluation after ORIF or CRIF. All cases in Group P had complete resolution of radial nerve palsy within 4 months postoperatively, and no case in Group C had postoperative iatrogenic radial nerve palsy.

CONCLUSIONS

Sonographic evaluation of the radial nerve at the first operation was a useful method to detect conditions of the nerve which can prevent compression or entrapment of the nerve and the need for secondary nerve exploration.

High radial nerve palsy

High radial palsy is primarily associated with humeral shaft fractures, whether primary due to the initial trauma, or secondary to their treatment. The majority will spontaneously recover, therefore early surgical exploration is mainly indicated for open fractures or if ultrasonography shows severe nerve damage. Initial signs of nerve recovery may appear between 2 weeks and 6 months. Otherwise, the decision to explore the nerve is based on the patient's age, clinical examination and electroneuromyography, as well as ultrasonography findings. If recovery does not occur, an autograft is indicated only in younger patients, before 6 months, if local conditions are suitable. Otherwise, nerve transfers performed by an experienced team give satisfactory results and can be offered up to 10 months post-injury. Tendon transfers are the gold standard treatment and the only option available beyond 10 to 12 months. The results are reliable and fast.

Acute Radial Nerve Repair with Humeral Shaft Shortening and Fixation Following a Closed Humeral Shaft Fracture: A Case Report

CASE

A 65-year-old woman sustained a closed segmental humeral shaft fracture with a complete radial nerve palsy. Radial nerve neurotmesis was found during acute surgical exploration and fixation. Treatment included a 2-cm shortening osteotomy of the humeral shaft and osteosynthesis in order to obtain a tension-free primary end-to-end repair of the radial nerve.

CONCLUSION

Tension-free primary nerve repair can be technically challenging with humeral shaft fractures. A shortening osteotomy of the humeral shaft and osteosynthesis are feasible to achieve tension-free neurorrhaphy without nerve-grafting.

Lateral intermuscular septum as cause of radial nerve compression: case report and review of the literature

Multiple sites of compression of the radial nerve have been described, some more commonly than others. In this case report we describe a case of radial nerve compression at the lateral intermuscular septum in a patient with a history of open reduction and internal fixation of a mid-shaft humerus fracture 10 years prior. To our knowledge, only one previous case of chronic radial nerve compression by the lateral intermuscular septum associated with a humeral shaft fracture has been described. Our patient’s clinical presentation with specific electrodiagnostic abnormalities, operative findings and post-operative symptom relief point towards the rare diagnosis of compression of the radial nerve at the level of the lateral intermuscular septum as the cause of his symptoms.