Fibular (peroneal) neuropathy.

Fibular neuropathy has variable presenting features depending on the site of the lesion. Anatomical features make it susceptible to injury from extrinsic factors, particularly the superficial location of the nerve at the head of the fibula. There are many mechanisms of compression or other traumatic injury of the fibular nerve, as well as entrapment and intrinsic nerve lesions. Intraneural ganglion cysts are increasingly recognized when the mechanism of neuropathy is not clear from the medical history. Electrodiagnostic testing can contribute to the localization as well as the characterization of the pathologic process affecting the nerve. When the mechanism of injury is unclear from the analysis of the presentation, imaging with MRI and ultrasound may identify nerve lesions that warrant surgical intervention. The differential diagnosis of foot drop includes fibular neuropathy and other neurologic conditions, which can be distinguished through clinical and electrodiagnostic assessment. Rehabilitation measures, including ankle splinting, are important to improve function and safety when foot drop is present. Fibular neuropathy is less frequently painful than many other nerve lesions, but when it is painful, neuropathic medication may be required. Failure to spontaneously recover or the detection of a mass lesion may require surgical management.

Joubert syndrome presenting bilateral peroneal neuropathies: A case report.

RATIONALE: Joubert syndrome (JS) is a rare genetic disorder that presents with various neurological symptoms, primarily involving central nervous system dysfunction. Considering the etiology of JS, peripheral nervous system abnormalities cannot be excluded; however, cases of JS accompanied by peripheral nervous system abnormalities have not yet been reported. Distinct radiological findings on brain magnetic resonance imaging were considered essential for the diagnosis of JS. However, recently, cases of JS with normal or nearly normal brain morphology have been reported. To date, there is no consensus on the most appropriate diagnostic method for JS when imaging-based diagnostic approach is challenging. This report describes the case of an adult patient who exhibited bilateral peroneal neuropathies and was finally diagnosed with JS through genetic testing. PATIENT CONCERNS AND DIAGNOSIS: A 27-year-old man visited our outpatient clinic due to a gait disturbance that started at a very young age. The patient exhibited difficulty maintaining balance, especially when walking slowly. Oculomotor apraxia was observed on ophthalmic evaluation. During diagnostic workups, including brain imaging and direct DNA sequencing, no conclusive findings were detected. Only nerve conduction studies revealed profound bilateral peroneal neuropathies. We performed whole genome sequencing to obtain a proper diagnosis and identify the gene mutation responsible for JS. LESSONS: This case represents the first instance of peripheral nerve dysfunction in JS. Further research is needed to explore the association between JS and peripheral nervous system abnormalities. Detailed genetic testing may serve as a valuable tool for diagnosing JS when no prominent abnormalities are detected in brain imaging studies.

Common fibular nerve palsy due to the Fabella: A review.

One of the most common nerve palsies - common fibular nerve palsy - can be caused by the variant small sesamoid bone in the posterolateral compartment of the knee joint known as the fabella. We compared and reviewed all reported cases of common fibular nerve palsy due to fabellae in the English literature. Compression can develop spontaneously or post-surgically (total knee arthroplasty). Symptoms progress rapidly to complete foot drop. Among all the cases reviewed, 68.42% were males with a median age of 39.39 years. Fabella compression was more common in the left common fibular nerve (CFN) (63.16%). Both big (23 × 20 × 16 mm) and small (5 × 5 mm) fabellae can be responsible for compression. While diagnosis can be problematic, the treatment (either surgical fabellectomy or conservative) is relatively easy and brings quick improvement.

Analysis of outcome reporting in common peroneal neuropathy studies: a systematic review of the literature.

BACKGROUND: There is a strong need for the development of core outcome sets (COS) across nerve surgery to allow for improved data synthesis, meta-analyses, and reporting consistency. Development of a core outcome set typically starts with assessing the literature for previously reported outcome measures. Common peroneal neuropathy (CPN) is the most common compressive mononeuropathy of the lower extremity and can result in pain, motor, and sensory deficits. A COS for COmmon PEroneal neuropathy (COS-COPE) is needed to improve future study design and comparison and synthesis of data. The goal of the current study was to assess the literature for outcomes reported in studies on CPN as the first step in the development of a COS. METHODS: A systematic review of the literature from 2000 to 2023 was performed utilizing PubMed and Medical Subject Headings (MeSH). Identified articles were screened according to study inclusion/exclusion criteria. Outcome measures reported in each included study were recorded and categorized into motor, sensory, pain, composite foot/ankle score, electrodiagnostics, function/disability patient-reported outcome (PRO), psychological, or other outcomes. Descriptive statistics were performed. RESULTS: A total of 31 articles met criteria for inclusion. A motor outcome was reported in 26 (83.9%) studies; 12 (38.7%) reported a sensory outcome; 8 (25.8%) reported a pain outcome; 4 (12.9%) reported a composite foot/ankle score; 3 (9.7%) reported electrodiagnostics; 1 (3.2%) reported a function/disability PRO; 1 (3.2%) reported a psychological outcome; 2 (6.5%) reported an imaging outcome; 3 (9.7%) reported other outcomes. Across the studies, 29 distinct outcome measures were reported. CONCLUSIONS: The outcomes reported in studies on CPN are varied and inconsistent. It is likely that a combination of motor, sensory, pain, and functional outcomes will be needed in a COS to best study CPN. These data will serve as a baseline for the ultimate development of the COS-COPE.

High Prevalence of Peroneal Neuropathy Among Children During the COVID-19 Pandemic.

OBJECTIVES: We aimed to explore the prevalence of peroneal neuropathy in children during coronavirus disease-19 (COVID-19) pandemic. BACKGROUND: Since the COVID-19 outbreak, many children worldwide have experienced a dramatic lifestyle changes, including conducting most daily activities indoors. Peroneal nerve palsy is one of the most common entrapment neuropathies and circumstances as prolonged immobilization or leg crossing predisposes an individual to peroneal neuropathy. METHODS: This is a case-control retrospective study that included patients referred to our neurophysiology clinic with foot drop. We compared the prevalence of spontaneous peroneal neuropathy 1 year before (April 2019/March 2020) and 1 year during the COVID-19 pandemic (April 2020/March 2021); and we also continued collecting data prospectively between April and September 2021 analysis the whole pandemic period. RESULTS: Totally, 399 patient clinical notes and NCS/EMG reports were reviewed, 220 were evaluated 1 year before and 179 1 year during COVID-19 pandemic. During the COVID-19 pandemic, there was a higher prevalence of peroneal neuropathy (odds ratio 4.74, 95%CI 1.30-17.25, p = 0.0183). In the COVID group (n = 11), mean age was 14 years and 63.4% were males. Mean age was 15 years and 66.7% were males in the Control group (n = 3). There was a significant difference in the time from symptoms onset to the neurophysiology assessment, with a mean time of 14 days in the Control group and 87.5 days in the COVID group. CONCLUSIONS: This study provides evidence that during the COVID-19 pandemic period, there was a higher prevalence of peroneal neuropathy among children. Strategies to prevent peroneal neuropathy should be recommened to this age group.

Bilateral peroneal nerve palsy due to prolonged squatting in farmers: clinical and electrophysiological outcome.

INTRODUCTION: Peroneal neuropathy is the most common mononeuropathy of the lower extremities. However, bilateral peroneal nerve palsy (BPNP) is extremely rare due to prolonged squatting. We aimed to evaluate the clinical-electrophysiological findings in patients with BPNP caused by long-term squatting for cotton harvesting in our region. METHODS: Eight patients (16 limbs), admitted to our center between February 2018 and March 2021 with bilateral foot drop after prolonged squatting, were included in our study. The clinical and electrophysiological findings were re-evaluated six months later. RESULTS: We observed that 18.75% of the limbs had pure conduction block, 31.25% had mixed involvement, and half had predominantly axonal damage. Good recovery was observed in ankle dorsiflexion in seven patients during follow-ups. None of the patients were referred for surgery. Electrophysiological examinations showed that the conduction block was resolved, and reinnervation was observed in all patients with axonal degeneration. CONCLUSION: Since the etiology is nontraumatic compression, good recovery can be seen with conservative treatment in BPNP. Electrophysiological studies may determine reinnervation along with clinical examination. The patient should be followed-up for six months with conservative treatment before surgical intervention.

Conservative versus surgical treatment of foot drop in peroneal nerve entrapment: rationale and design of a prospective, multi-centre, randomized parallel-group controlled trial.

BACKGROUND: High-quality evidence is lacking to support one treatment strategy over another in patients with foot drop due to peroneal nerve entrapment. This leads to strong variation in daily practice. METHODS/DESIGN: The FOOTDROP (Follow-up and Outcome of Operative Treatment with Decompressive Release Of The Peroneal nerve) trial is a randomized, multi-centre study in which patients with peroneal nerve entrapment and persistent foot drop, despite initial conservative treatment, will be randomized 10 (± 4) weeks after onset between non-invasive treatment and surgical decompression. The primary endpoint is the difference in distance covered during the 6-min walk test between randomization and 9 months later. Time to recovery is the key secondary endpoint. Other secondary outcome measures encompass ankle dorsiflexion strength (MRC score and isometric dynamometry), gait assessment (10-m walk test, functional ambulation categories, Stanmore questionnaire), patient-reported outcome measures (EQ5D-5L), surgical complications, neurological deficits (sensory changes, motor scores for ankle eversion and hallux extension), health economic assessment (WPAI) and electrodiagnostic assessment. DISCUSSION: The results of this randomized trial may elucidate the role of surgical decompression of the peroneal nerve and aid in clinical decision-making. TRIAL REGISTRATION: ClinicalTrials.gov NCT04695834. Registered on 4 January 2021.

Acute-Onset Footdrop Caused by Intraneural Ganglion Cyst of the Common Peroneal Nerve: The Effects of Extraneural Pressure Gradients on Cyst Propagation.

Ganglion cysts are relatively common entities, but intraneural ganglia within peripheral nerves are rare and poorly understood. We present a case of a 51-year-old man who presented with acute left dropfoot. Initial magnetic resonance imaging (MRI) was misinterpreted as common peroneal neuritis consistent with a traction injury corroborated by the patient's history. However, after surgical decompression and external neurolysis were performed, the patient's symptoms worsened. Repeated MRI revealed an intraneural ganglion cyst of the common peroneal nerve with connection to the superior tibiofibular joint by means of its anterior recurrent branch that was evident retrospectively on preoperative MRI. It is crucial to carefully inspect atypical cases to further recognize and appreciate the dynamic aspect of this disease or "roller-coaster" phenomenon. Intraneural ganglion cysts rely heavily on intraneural and extraneural pressure gradients for propagation, which can be drawn from the expanded work of the unifying articular theory. This report emphasizes the importance of understanding the pathoanatomical and hydraulic factors to appropriately identify and treat intraneural ganglion cysts. Increased recognition of this pathologic entity as a differential diagnosis for acute onset dropfoot is also highlighted.

An overview of common peroneal nerve dysfunction and systematic assessment of its relation to falls.

PURPOSE: Compression of the peroneal nerve is recognized as a common cause of falls. The superficial course of the peroneal nerve exposes it to trauma and pressure from common activities such as crossing of legs. The nerve can be exposed also to distress due to metabolic problems such as diabetes. The purpose of our manuscript is to review common peroneal nerve dysfunction symptoms and treatment as well as provide a systematic assessment of its relation to falls. METHODS: We pooled the existing literature from PubMed and included studies (n = 342) assessing peroneal nerve damage that is related in any way to falls. We excluded any studies reporting non-original data, case reports and non-English studies. RESULTS: The final systematic assessment included 4 articles. Each population studied had a non-negligible incidence of peroneal neuropathy. Peroneal pathology was found to be consistently associated with falls. CONCLUSION: The peroneal nerve is an important nerve whose dysfunction can result in falls. This article reviews the anatomy and care of the peroneal nerve. The literature review highlights the strong association of this nerve's pathology with falls.

Superficial peroneal nerve entrapment neuropathy and role of pulsed radiofrequency neuromodulation.

Peripheral neuropathy secondary to entrapment of the nerves is not an uncommon etiology. Nerve entrapment is a common occurrence following trauma or surgery and poses significant diagnostic challenge. Entrapment neuropathy (EN) may not respond to standard neuropathic medication and may need invasive treatment. Pulsed radiofrequency (PRF) application is a recent modality and is gaining popularity for many EN as it does not cause neural ablation unlike conventional radiofrequency ablation. In this report, we present a case of young patient who presented with severe lower lateral leg pain in whom superficial peroneal nerve (SPN) EN was suspected and diagnostic SPN injection under ultrasound guidance confirmed the diagnosis. He subsequently underwent PRF neuromodulation and experienced long-lasting pain relief.

Delayed Onset of Peroneal Nerve Palsy After Total Knee Arthroplasty.

Peroneal nerve palsy (PNP) and peroneal nerve dysfunction (PND) are rare complications after total knee arthroplasty (TKA). Although PND tends to manifest as transient lateral leg paresthesias that are associated with knee motion, PNP has characteristic motor deficits, including loss of ankle dorsiflexion and eversion strength. Although PND can manifest days, weeks, or months after surgery, delayed cases of PNP have not been well documented. We describe a 72-year-old woman with a delayed case of sudden-onset PNP 10 weeks after TKA. She had no neurologic deficits preoperatively and was recovering uneventfully at 2 and 6 weeks postoperatively. At 10 weeks, she reported insidious onset of drop foot and sensory changes to the lateral leg and dorsum of the foot. Motor deficits included significant loss of ankle dorsiflexion and eversion strength. After a diagnosis of PNP was confirmed with electrodiagnostic studies and lumbar pathology was ruled out with lumbar magnetic resonance imaging, surgical decompression of the peroneal nerve was performed. By 7 weeks after surgical decompression, she had no sensory deficits and nearly full strength in ankle dorsiflexion and eversion. This case shows that PNP can occur several weeks to months outside of the currently documented timeline. Although PNP is an uncommon risk of TKA, it is important to recognize and treat it when it occurs among patients with significant motor and sensory deficits along the distribution of the peroneal nerve postoperatively. [Orthopedics. 2022;45(6):e342-e344.].

Common peroneal nerve palsy after primary total hip arthroplasty.

PURPOSE: The study wants to evaluate the incidence, the clinical evolution, and treatment of common peroneal nerve (CPN) palsy after primary total hip arthroplasty. METHODS: Our clinical prospective study was made between January 2016 and December 2020. The study group comprised 1240 total hip replacements over a period of five years. Six cases were diagnosed with CPN palsy (0.48%). Five were women and one man, aged from 52 to 71 years old. The common peroneal nerve lesion was diagnosed clinically and by electromyography. RESULTS: The follow-up period was at least 24 months post-operatively. In all six cases, there was a complete common peroneal nerve palsy, documented by electromyography. The poorest results were obtained in the older patients and those who had the highest body mass index, which at two years post-operatively achieved only a partial sensory rehabilitation, with complete motor deficit. All patients can walk unassisted, without support, with one case having complete rehabilitation achieved 18 months postoperatively and three with partial rehabilitation. CONCLUSION: CPN palsy after primary THA is a very serious complication with poor functional outcome. There is no consensus regarding the treatment. The age and the intensity of the rehabilitation program are the only significant factors for the medical rehabilitation after this debilitating post-operative complication.

Common fibular nerve palsy due to fabella compression: An illustrative case report.

BACKGROUND: The fabella is a sesamoid bone situated in the tendon of the lateral head of the gastrocnemius muscle behind the lateral femoral condyle. Common fibular nerve injury may occur anywhere on its course and the most common etiology remains compression at the level of the head of the fibula. Compression by a fabella is a very unusual cause of common fibular nerve palsy and only few case reports are described in the literature. We present here an illustrative case. CASE DESCRIPTION: A 50-year-old female patient presented with a left drop-foot evolving for two weeks without pain or sensory deficit. Clinical examination revealed a paresis of the left foot dorsiflexors muscles (3/5). A compressive neuropathy of the common fibular nerve at the level of the fibula head was demonstrated by nerve conduction studies. Ultrasound of the left knee revealed nerve compression by a fabella. Early decompressive surgery was performed and the fabella was excised. We noticed an almost complete recovery probably due to early treatment (4+/5 two months after surgery). CONCLUSIONS: Common fibular nerve palsy related to fabella compression is very uncommon. Good clinical outcome has been described at 1-2 years with an early work-up and a prompt surgical decompression.

Surgical Treatment of Foot Drop: Patient Evaluation and Peripheral Nerve Treatment Options.

Foot drop is a common clinical condition which may substantially impact physical function and health-related quality of life. The etiologies of foot drop are diverse and a detailed history and physical examination are essential in understanding the underlying pathophysiology and capacity for spontaneous recovery. Patients presenting with acute foot drop or those without significant spontaneous recovery of motor deficits may be candidates for surgical intervention. The timing, mechanism, and severity of neural injury resulting in foot drop influence the selection of the most appropriate peripheral nerve surgery, which may include direct nerve repair, neurolysis, nerve grafting, or nerve transfer.

Complete Foot Drop With Normal Electrodiagnostic Studies: Sunderland "Zero" Ischemic Conduction Block of the Common Peroneal Nerve.

ABSTRACT: Common peroneal neuropathy is a peripheral neuropathy of multifactorial etiology often left undiagnosed until foot drop manifests and electrodiagnostic abnormalities are detected. However, reliance on such striking symptoms and electrodiagnostic findings for diagnosis stands in contrast to other commonly treated neuropathies, such as carpal tunnel and cubital tunnel syndrome. Poor recognition of common peroneal neuropathy without foot drop or the presence of foot drop with normal electrodiagnostic studies thus often results in delayed or no surgical treatment. Our cases document 2 patients presenting with complete foot drop who had immediate resolution after decompression. The first patient presented with normal electrodiagnostic studies representing an isolated Sunderland Zero nerve ischemia. The second patient presented with severe electrodiagnostic studies but also had an immediate improvement in their foot drop representing a Sunderland VI mixed nerve injury with a significant contribution from an ongoing Sunderland Zero ischemic conduction block. In support of recent case series, these patients demonstrate that common peroneal neuropathy can present across a broad diagnostic spectrum of sensory and motor symptoms, including with normal electrodiagnostic studies. Four clinical subtypes of common peroneal neuropathy are presented, and surgical decompression may thus be indicated for these patients that lack the more conventional symptoms of common peroneal neuropathy.

Arthroscopic Treatment of Lateral Meniscal Cyst Causing Peroneal Nerve Injury.

Compression of the common peroneal nerve by lateral meniscal cysts is rare. We report a 29-year male patient who complained of a gradually enlarging mass in the right popliteal fossa. He was diagnosed with a lateral meniscal cyst and a common peroneal nerve injury. The patient underwent arthroscopic surgery, including lateral partial meniscectomy and cyst drainage. When followed up at 3 months, the dorsal extensor strength of the right foot recovered to grade 5, and sensation of the distal right lower limb returned to normal. No recurrence of the cyst was found at the last follow-up at 18 months. This is a rare case of common peroneal nerve paralysis caused by a lateral meniscal cyst. Key Words: Meniscal cyst, Common peroneal nerve, Nerve injury.