Common Peroneal Nerve and Tarsal Tunnel Release Surgery in an Adolescent Male with Hunter Syndrome: Illustrative Case.

BACKGROUND: Children with Hunter syndrome have a high prevalence of nerve compression syndromes given the buildup of glycosaminoglycans in the tendon sheaths and soft tissue structures. These are often comorbid with orthopedic conditions given joint and tendon contractures due to the same pathology. While carpal tunnel syndrome and surgical treatment has been well-reported in this population, the literature on lower extremity nerve compression syndromes and their treatment in Hunter syndrome is sparse. OBSERVATIONS: We report the case of a 13-year-old male with a history of Hunter syndrome who presented with toe-walking and tenderness over the peroneal and tarsal tunnel areas. He underwent bilateral common peroneal nerve and tarsal tunnel releases, with findings of severe nerve compression and hypertrophied soft tissue structures demonstrating fibromuscular scarring on pathology. Post-operatively, the patient's family reported subjective improvement in lower extremity mobility and plantar flexion. LESSONS: In this case, peroneal and tarsal nerve compression were diagnosed clinically and treated effectively with surgical release and postoperative ankle casting. Given the wide differential of common comorbid orthopedic conditions in Hunter syndrome and the lack of validated electrodiagnostic normative values in this population, the history and physical examination and consideration of nerve compression syndromes are tantamount for successful workup and treatment of gait abnormalities in the child with Hunter syndrome.

Functional outcomes of different surgical treatments for common peroneal nerve injuries: a retrospective comparative study.

BACKGROUND: This study aims to assess the recovery patterns and factors influencing outcomes in patients with common peroneal nerve (CPN) injury. METHODS: This retrospective study included 45 patients with CPN injuries treated between 2009 and 2019 in Jing'an District Central Hospital. The surgical interventions were categorized into three groups: neurolysis (group A; n = 34 patients), nerve repair (group B; n = 5 patients) and tendon transfer (group C; n = 6 patients). Preoperative and postoperative sensorimotor functions were evaluated using the British Medical Research Council grading system. The outcome of measures included the numeric rating scale, walking ability, numbness and satisfaction. Receiver operating characteristic (ROC) curve analysis was utilized to determine the optimal time interval between injury and surgery for predicting postoperative foot dorsiflexion function, toe dorsiflexion function, and sensory function. RESULTS: Surgical interventions led to improvements in foot dorsiflexion strength in all patient groups, enabling most to regain independent walking ability. Group A (underwent neurolysis) had significant sensory function restoration (P < 0.001), and three patients in Group B (underwent nerve repair) had sensory improvements. ROC analysis revealed that the optimal time interval for achieving M3 foot dorsiflexion recovery was 9.5 months, with an area under the curve (AUC) of 0.871 (95% CI = 0.661-1.000, P = 0.040). For M4 foot dorsiflexion recovery, the optimal cut-off was 5.5 months, with an AUC of 0.785 (95% CI = 0.575-0.995, P = 0.020). When using M3 toe dorsiflexion recovery or S4 sensory function recovery as the gold standard, the optimal cut-off remained at 5.5 months, with AUCs of 0.768 (95% CI = 0.582-0.953, P = 0.025) and 0.853 (95% CI = 0.693-1.000, P = 0.001), respectively. CONCLUSIONS: Our study highlights the importance of early surgical intervention in CPN injury recovery, with optimal outcomes achieved when surgery is performed within 5.5 to 9.5 months post-injury. These findings provide guidance for clinicians in tailoring treatment plans to the specific characteristics and requirements of CPN injury patients.

Pediatric Peroneal Nerve Palsy Secondary to Fibular Osteochondroma.

Peripheral nerve injuries due to mass effect from bony lesions can occur when the nerve exists in an anatomically constrained location, such as the common peroneal nerve at the fibular head which passes into the tight fascia of the lateral leg compartment. We report a case of a pediatric patient who developed a common peroneal nerve palsy secondary to an osteochondroma of the fibular head and describe the clinical evaluation, radiographic findings, and surgical approach. Rapid diagnosis and nerve decompression after the onset of symptoms restored full motor function at the 8-month postoperative mark.

Intraneural ganglion cyst of the peroneal nerve occurring after coronavirus disease-19 vaccination: A case report.

Ganglion cysts are relatively common, but intraneural ganglion cysts (INGCs) within peripheral nerves are rare and poorly understood. We present the case of a 58-year-old woman who presented with acute right-foot drop. She experienced acute knee pain radiating from the lateral leg to the dorsal foot two days after the first coronavirus disease-19 (COVID-19) vaccination (BNT162b2, Pfizer-BioNTech). She had no history of trauma or medication use. Two weeks after the onset of symptoms, she developed a dorsiflexor weakness of the right foot (Medical Research Council grade, poor). The weakness worsened to a "trace" grade despite providing conservative management for one month. Ultrasonography revealed a fusiform echolucent structure within the course of the right common peroneal nerve around the fibular head. Magnetic resonance imaging revealed multiple intraneural cysts within the right common peroneal nerve. Nerve conduction and electromyographic studies revealed multiphasic motor unit action potentials accompanied by abnormal spontaneous activities in the innervated muscles, along with axonal degeneration of the deep peroneal nerves. Surgical removal of the cyst was performed, and the patient's symptoms gradually improved. Pathological examination revealed a cystic structure containing mucinous or gelatinous fluid and lined with flattened or cuboidal cells. The clinical course and sequential electromyographic findings relevant to this symptomatic cyst were temporally related to the vaccination date. The present case suggests that INGC-induced peroneal palsy is a possible complication after COVID-19 vaccination.

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.

Motor and sensory nerve transfers in the lower extremity: Systematic review of current reconstructive possibilities.

BACKGROUND: Peripheral nerve injuries (PNI) are predominantly treated by anatomical repair or reconstruction with autologous nerve grafts or allografts. Motor nerve transfers for PNI in the upper extremity are well established; however, this technique is not yet widely used in the lower extremity. This literature review presents an overview of the current options and postoperative results for nerve transfers as a treatment for nerve injury in the lower extremity. METHODS: A systematic search in PubMed and Embase databases was performed. Full-text English articles describing surgical procedures and postoperative outcomes of nerve transfers in the lower extremity were included. The primary outcome was postoperative muscle strength measured using the British Medical Research Council (MRC) scale, with MRC> 3 considered good and postoperative return of sensation reported according to the modified Highet classification. RESULTS: A total of 36 articles for motor nerve transfer and 7 for sensory nerve transfer were included. Sixteen articles described motor nerve transfers for treating peroneal nerve injury, 17 for femoral nerve injury, 2 for tibial nerve injury, and one for obturator nerve injury. Transfers of multiple branches to restore deep peroneal nerve function led to a good outcome in 58% of patients and 43% when a single branch was used as a donor. The transfer of multiple branches for femoral nerve or obturator nerve repair was performed in all reported patients with a good outcome. CONCLUSIONS: The transfer of motor nerves for the recovery of PNI is a feasible technique with relatively low risks and great benefits. The correct indication, timing, and surgical technique are essential for optimizing results.

Surgical Outcomes of Common Peroneal Nerve Entrapment Neuropathy Associated with L5 Radiculopathy.

Impingement of the common peroneal nerve, a branch of the L5 nerve root, causes common peroneal nerve entrapment neuropathy (CPNE). Although there are cases of CPNE associated with L5 radiculopathy, surgical intervention's effectiveness remains to be elucidated. This retrospective case-control study aimed to evaluate the efficacy of surgery in patients with CPNE associated with L5 radiculopathy. Twenty-two patients (25 limbs) with surgically treated CPNE between 2015 and 2022 were retrospectively reviewed. The limbs were classified into two groups: group R (limbs of CPNE associated with L5 radiculopathy) and group O (limbs of CPNE without L5 radiculopathy). The durations from onset to surgery, the nerve conduction studies (NCSs), and postoperative improvement rates for motor weakness, pain, and dysesthesia were compared between the groups. Group R included 15 limbs (13 patients), and group O included 10 limbs (9 patients). There were no significant differences in the duration from onset to surgery or abnormal findings of NCS between the two groups. The postoperative improvement rates were 88% and 100% (p = 0.62) for muscle weakness, 87% and 80% (p = 0.53) for pain, and 71% and 56% (p = 0.37) for dysesthesia in group R and group O, respectively, without significant differences between groups. CPNE associated with L5 radiculopathy is common, and the results of the present study showed that the surgical outcomes in such cases were satisfactory and comparable to those in CPNE without L5 radiculopathy.

Partial tibial nerve transfer for iatrogenic peroneal nerve palsy after endovenous laser ablation for varicose veins of the lower extremity: A case report.

Postprocedural peroneal nerve palsy after endovenous laser ablation (EVLA) for varicose veins is rare and is associated with poor functional recovery. There have been no reports using tibial nerve transfer for iatrogenic peroneal nerve palsy after EVLA. Herein, we present a case with peroneal nerve injury after EVLA, which was successfully treated by partial tibial nerve transfer for the first time. A 75-year-old female presented with a right foot drop immediately after EVLA of the lesser saphenous vein. The ankle and toe dorsiflexion had a muscle grade of M0 on the British Medical Research Council muscle scale, without voluntary motor unit action potentials (MUAP) in the tibialis anterior (TA) muscle on the needle electromyography. Three months after the injury, surgical nerve exploration revealed a damaged common peroneal nerve with discoloration and scarring at the fibular head. Intraoperative deep peroneal nerve stimulation confirmed the absence of compound muscle action potentials in the TA. The best functioning motor fascicles of the tibial nerve were transferred to the deep peroneal main trunk involving motor branches of the TA, extensor digitorum longus, and extensor hallucis longus (EHL) through the interosseous membrane. The postoperative course was uneventful, with no complications. After 3 months of surgery, nascent MUAP appeared in the TA. After 24 months, the patient regained the TA and EHL muscle function and ambulation without an ankle-foot orthosis and tibial nerve deficits. Thus, our procedure may serve as an alternative to nerve grafting, tendon transfer, and orthoses for better management of the major neural complications associated with EVLA.

Common Peroneal Nerve Injury Due to an All-Inside Repair of the Posterior Horn of Lateral Meniscus: A Case Report.

CASE: An 18-year-old man sustained a peroneal nerve (PN) injury during an all-inside repair of the posterior horn of the lateral meniscus from the medial portal. Although he could dorsiflex his ankle actively after emergence from general anesthesia, he had a foot drop on the day after surgery. Exploration of the PN at 5 months postoperatively revealed that the nerve was entrapped by the suture. Fifteen months after a nerve repair using a sural nerve graft, he recovered from the foot drop. CONCLUSION: This case report highlights the risk of PN injury during an all-inside repair of the posterior horn of the lateral meniscus.

Tendon transfer in foot drop: a systematic review.

INTRODUCTION: Foot drop is a disorder that impairs walking and leads to tripping and falling. Tendon transfer (e.g., tibialis posterior tendon) is a typical secondary procedure in foot drop treatment. The purpose of this systematic review was to identify the most common tendon transfer techniques for treating foot drop and to analyze the reported functional outcomes. Furthermore, it was of interest if the type of surgical technique affects the functional outcome. METHODS: A PubMed and MEDLINE literature search was performed according to PRISMA guidelines. The search terms used were ("tendon transfer" OR "tendon transposition") AND ("foot drop" OR "peroneal neuropathies"). Any study published before January 2020 was considered for inclusion. No case reports or reviews were included. Common outcome measures (Stanmore score, AOFAS, FAAM, AFO use, patient satisfaction and active ankle dorsiflexion) were evaluated. The quality of the included studies was assessed using the Coleman Methodology Score. RESULTS: Of the 125 reviewed publications, 37 met the inclusion criteria. 42 cohorts were analyzed. The frequently reported tendon transfer technique was the tibialis posterior tendon transfer through the interosseus membrane. The most used fixation technique was tendon on tendon fixation; however in recent years, a tendon to bone fixation has gained popularity. There was an increase in Stanmore scores and AOFAS postoperatively and a decrease of AFO use postoperatively observed. CONCLUSIONS: Due to various outcome measures and lack of preoperative assessment in the included studies, a meta-analysis of the pooled results was not possible. Nevertheless, the findings of this study show that tendon transfer increases mobility and self-independency leading to patient satisfaction. The choice of the surgical technique does not affect the outcome. A prospective collection of patient data and standardized outcome measures will be important to further analyze the efficacy of tendon transfer techniques.

Paralysis Immediately after Surgical Decompression for Common Peroneal Nerve Entrapment.

OBJECTIVE: Common peroneal nerve (C-PN) entrapment neuropathy is the most common peripheral nerve neuropathy of the legs. C-PN decompression surgery is less invasive but may result in neurological complications. We report a rare case of nerve paralysis immediately after C-PN decompression surgery. CASE REPORT: An 85-year-old man presented with leg numbness and pain. An electrophysical study revealed C-PN entrapment in the affected area and he underwent surgical decompression. Immediately after the procedure he complained of slight paralysis without pain (manual muscle test: 3/5), which gradually worsened and was complete at 60 min after surgery. We re-opened the skin incision 3 hours after the first operation and found that a subcutaneous suture had been applied to the connective tissue near the C-PN, resulting in marked compression of the nerve. After release of the suture his paralysis improved immediately. We confirmed that there was no other nerve compression and finished the operation. His paralysis disappeared completely. CONCLUSION: Peripheral nerve surgery, including C-PN decompression surgery, is less invasive, and the risk of complications is low. However, because the C-PN is located in the shallow layer under the skin, an excessively deep suture in the subcutaneous layer may compress the nerve and elicit nerve palsy. Therefore, careful postoperative follow-up is necessary because early decompression leads to good surgical results.

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.

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.

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.].

Incidences, causes and risk factors of unplanned reoperations within 30 days of spine surgery: a single-center study based on 35,246 patients.

BACKGROUND CONTEXT: Unplanned reoperation, a quality indicator in spine surgery, has not been sufficiently investigated in a large-scale, single-center study. PURPOSE: To assess the incidences, causes, and risk factors of unplanned reoperations within 30 days of spine surgeries in a single-center study. STUDY DESIGN: Retrospective observational study. PATIENT SAMPLE: A cohort of 35,246 patients who underwent spinal surgery in our hospital were included. OUTCOME MEASURES: The rates, chief reasons, and risk factors for unplanned reoperations within 30 days of spine surgery. METHODS: We retrospectively analyzed the data for patients who underwent spine surgeries for degenerative spinal disorders, tumor, or deformity and had subsequent unplanned operations within 30 days at a single tertiary academic hospital from January 2016 to July 2021. Univariate and multivariate analyses were performed to assess the incidences, causes, and risk factors. RESULTS: Out of 35,246 spinal surgery patients, 297 (0.84%) required unplanned reoperations within 30 days of spine surgery. Patients with a thoracic degenerative disease (3.23%), spinal tumor (1.63%), and spinal deformity (1.50%) had significantly higher rates of reoperation than those with atlantoaxial (0.61%), cervical (0.65%), and lumbar (0.82%) degenerative disease. The common causes for reoperation included epidural hematoma (0.403%), wound infections (0.148%), neurological deficit (0.108%), and pedicle screw malposition (0.077%). Unplanned reoperations were classified as hyperacute (45.45%), acute (30.98%), subacute (15.82%), or chronic (7.74%). Univariate analysis indicated that 20 clinical factors were associated with unplanned reoperation (p<.05). Multivariate Poisson regression analysis revealed that anemia (p<.001), osteoporosis (p=.048), ankylosing spondylitis (p=.008), preoperative foot drop (p=.011), deep venous thrombosis (p<.001), and previous surgical history (p<.001) were independent risk factors for unplanned spinal reoperation. CONCLUSIONS: The incidence of unplanned spinal reoperations was 0.84%. The chief common causes were epidural hematoma, wound infections, neurological deficit, and pedicle screw malposition. Anemia, osteoporosis, ankylosing spondylitis, preoperative foot drop, deep venous thrombosis, and previous surgical history led to an increased risk of unplanned reoperation within 30 days of spine surgery.

Comparison of Isolated Sciatic Nerve and Sacral Nerve Root Endometriosis: A Review of the Literature.

OBJECTIVE: This review aimed to compare isolated sciatic and sacral nerve root endometriosis in terms of anatomic distribution, patients' symptoms and history, diagnostics, treatments, and outcomes. DATA SOURCE: We searched PubMed, MEDLINE, Web of Science, and Embase from inception to October 2021 using a combination of keywords including "sciatic nerve endometriosis," "sacral nerve root endometriosis," and associated Medical Subject Headings. Relevant publications and references were also checked for further articles. METHODS OF STUDY SELECTION: Two independent researchers performed the study selection. We included all original research articles, case reports, and case series in English that reported on the isolated sciatic nerve and sacral nerve root endometriosis. TABULATION, INTEGRATION, AND RESULTS: The initial search identified 92 articles, and 40 articles, mostly case reports and case series, were included. The review included 362 patients: with 256 and 106 patients in the sacral and the sciatic groups, respectively. In both groups, most patients had right-sided endometriosis. In the sciatic group, most of the patients presented with foot drop, leg motor weakness, and sciatic dermatome hypoesthesia. The frequencies of all these symptoms were significantly higher in the sciatic group (all p <.001). By contrast, in the sacral group, most of patients presented with pudendal neuralgia (p <.001). Intraoperative, early, late, and 1-year postoperative complications did not differ significantly between the 2 groups. CONCLUSION: This study indicated that isolated sciatic and sacral nerve root endometrioses were more common on the right side. Laparoscopic surgery was more commonly performed over traditional open or transgluteal surgery techniques. Sacral nerve root endometriosis is often accompanied by deep infiltrating endometriosis. Magnetic resonance imaging and myelography may be useful diagnostic tools in the preoperative workup. There was usually no significant improvement after surgery in cases of isolated sciatic nerve endometriosis presenting with foot drop.

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.

Development of a New Ankle Joint Hybrid Assistive Limb.

Foot and ankle disabilities (foot drop) due to common peroneal nerve palsy and stroke negatively affect patients' ambulation and activities of daily living. We developed a novel robotics ankle hybrid assistive limb (HAL) for patients with foot drop due to common peroneal nerve palsy or stroke. The ankle HAL is a wearable exoskeleton-type robot that is used to train plantar and dorsiflexion and for voluntary assistive training of the ankle joint of patients with palsy using an actuator, which is placed on the lateral side of the ankle joint and detects bioelectrical signals from the tibialis anterior (TA) and gastrocnemius muscles. Voluntary ankle dorsiflexion training using the new ankle HAL was implemented in a patient with foot drop due to peroneal nerve palsy after lumbar surgery. The time required for ankle HAL training (from wearing to the end of training) was approximately 30 min per session. The muscle activities of the TA on the right were lower than those on the left before and after ankle HAL training. The electromyographic wave of muscle activities of the TA on the right was slightly clearer than that before ankle HAL training in the resting position immediately after ankle dorsiflexion. Voluntary ankle dorsiflexion training using the novel robotics ankle HAL was safe and had no adverse effect in a patient with foot drop due to peroneal nerve palsy.

Soft Tissue Management and Tibialis Posterior Tendon Transfer in Acute Correction for Neglected Drop Foot Deformity.

Acute correction of rigid drop foot deformity can be problematic due to the skin defect that may occur in the medial part of the ankle. The purpose of this study is to present an innovative solution for this problem. We hypothesized that acute correction for rigid ankle contractures without arthrosis might be possible if the medial skin defect could be closed. Therefore, we described a surgical technique for acute functional correction of rigid drop foot deformities. The closure of the medial defect was performed by applying a flap and partial-thickness skin graft. We have retrospectively evaluated the results of 18 patients who were treated between 2010 and 2016 with this technique. The mean age of the patients was 37 ± 9.5 (22-56) years. Foot drop etiology was firearm-related nerve injury. Corrections were performed after 14.6 ± 7.9 (8-38) months following the injury. At the end of an average follow-up period of 44.4 ± 6.2 (37-60) months, 14 of 18 patients (78%) recovered without complications, 3 patients experienced partial loss in the medial skin graft region, and 1 patient developed a superficial infection. None of the patients have developed pes planus. We observed that the ankle flexion contracture, which was 34° ± 9.2° (20°-50°) preoperatively, could reach an average of 2.2° ± 2.5° (0°-6°) dorsiflexion after surgery. We suggest that acute correction and tibialis posterior tendon transfer in the treatment of rigid foot drop deformity can be performed with an effective skin closure with low soft tissue complications.