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.

The Muscle Shortening Maneuver: a noninvasive approach to the treatment of peroneal nerve injury. A case report

BACKGROUND

The treatment of peripheral nerve injuries is a debated topic. The Muscle Shortening Maneuver (MSM), a physiotherapy approach, is noninvasive and free of side effects; it consists of a muscle shortening and a solicitation in traction applied simultaneously.

OBJECTIVE

The focus of this report is to describe the effects of the MSM combined with walking retraining in a patient with incomplete injury of the peroneal nerve.

DESCRIPTION

The patient was a 17-year-old man, who underwent osteotomy surgery of the proximal two-thirds of the fibula, due to an Ewing sarcoma that caused a partial injury of the left peroneal nerve. Our assessment plan of the left ankle movement ability comprised range of movement, muscle strength, and surface electromyography (EMG); and a gait analysis was conducted by using an iPhone application. MSM and walking retraining were administered twice and once a week, respectively, for 4 weeks.

OUTCOMES

The active range of movement substantially improved in dorsiflexion (≥15°), whereas slightly decreased in plantar flexion (-5°). Aside from the tibialis anterior, an increase in muscle strength was detected. Surface EMG showed an increased activation, particularly in the peroneus longus. A decrease in gait speed and step length was recorded from the gait analysis, with a better bilateral symmetry.

CONCLUSIONS

Positive outcomes were reported without evidence of risk or adverse events for the participant.

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.

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.

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.

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.

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.].

Foot Drop, Hindfoot Varus, and Tibialis Posterior Tendon Transfer in Cerebral Palsy

The transfer of the tibialis posterior tendon has been used to correct hindfoot varus and dorsiflexion weakness in cerebral palsy. It is expendable, has a favorable direction for dorsiflexion and eversion posterior to the tibia, and is the source of hindfoot varus in most cases. However, the foot and ankle must be flexible without skeletal deformity. The electromyography of the tibialis posterior should be present in the swing phase for the tendon transfer to function correctly. Techniques and pitfalls are described to plan and execute a successful tibialis posterior tendon 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.

Traumatic Peroneal Nerve Injuries: A Systematic Review

BACKGROUND

The common peroneal nerve (CPN) is the most commonly injured peripheral nerve of the lower extremity in patients with trauma. Traumatic CPN injuries have historically been associated with relatively poor outcomes and patient satisfaction, although improved surgical technique and novel procedures appear to improve outcomes. Given the variety of underlying injury modalities, treatment options, and prognostic variables, we sought to evaluate and summarize the current literature on traumatic CPN injuries and to provide recommendations from an analysis of the included studies for treatment and future research.

METHODS

A systematic review was performed using PubMed, Embase, and Cochrane databases per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Search terms consisted of variations of "peroneal nerve" or "fibular nerve" combined with "injury," "laceration," "entrapment," "repair," or "neurolysis." Information with regard to treatment modality, outcomes, and patient demographic characteristics was recorded and analyzed.

RESULTS

The initial search yielded 2,301 articles; 42 met eligibility criteria. Factors associated with better outcomes included a shorter preoperative interval, shorter graft length when an interposed graft was used, nerve continuity, and younger patient age. Gender or sex was not mentioned as a factor affecting outcomes in any study. Motor grades of ≥M3 on the British Medical Research Council (MRC) scale are typically considered successful outcomes. This was achieved in 81.4% of patients who underwent neurolysis, 78.8% of patients who underwent end-to-end suturing, 49.0% of patients who underwent nerve grafting, 62.9% of patients who underwent nerve transfer, 81.5% of patients who underwent isolated posterior tibial tendon transfer (PTTT), and 84.2% of patients who underwent a surgical procedure with concurrent PTTT.

CONCLUSIONS

Studies included in this review were heterogenous, complicating our ability to perform further analysis. It is not possible to uniformly advocate for the best treatment option, given diverse injury modalities and patient presentations and a variety of prognostic factors. Many studies do not show outcomes with respect to injury modality. Future studies should show preoperative muscle strengths and should clearly define outcomes based on the injury modality and surgical treatment option. This would allow for greater analysis of the most appropriate treatment option for a given mechanism of injury. Newer surgical techniques are promising and should be further explored.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

[Differential Diagnosis between Spinal Degenerative Disorder and Peripheral Nerve Entrapment Disease]

In the surgical treatment of spinal degenerative disorders, neural function improves to some extent upon successful neural decompression. However, we have witnessed cases with poor postoperative results. The causes include surgical procedure issues, such as insufficient decompression of neural tissues and overlooking sites to be decompressed, and neurological misdiagnosis of other causative lesions or multiple lesions. Here, as necessary knowledge for spine surgeons dealing with spinal cord degenerative disorders to prevent poor surgical results, we have discussed the differentiation of peripheral nerve entrapment neuropathy from spinal degenerative disorders. Specifically, we have focused on L5 radiculopathy or common peroneal nerve entrapment disorder and C8 radiculopathy or thoracic outlet syndrome or ulnar nerve entrapment neuropathy, which are difficult to distinguish, and have explained the difference in their neurological symptoms from an anatomical perspective. We have also described the differential diagnosis of drop fingers, which is one of the neurological symptoms, and have mentioned the possibility of diseases managed by neurologists, which neurosurgeons should know about.

Acute Common Peroneal Nerve Decompression After Total Knee Arthroplasty

Common peroneal nerve palsy (CPNP) after total knee arthroplasty has a reported incidence of 0.3% to 4% and can lead to foot drop, equinovarus deformity, and marked disability if not resolved. Patients typically present in the early postoperative period with weakness or inability to dorsiflex the ankle and decreased sensation of the dorsum of the foot. The authors report their experience, technique, and outcomes of acute peroneal decompression within the first 90 days postoperatively for 5 patients with this unique complication. Preoperatively, all patients had valgus deformity with intact dorsiflexion and sensation of the foot. The diagnosis of CPNP was made on postoperative day 0 or 1 in all cases. After diagnosis, patients were offered acute peroneal decompression and returned to the operating room electively. The surgical technique for dissection, release, and decompression of the nerve is described. At an average follow-up of 12 weeks (range, 6-16 weeks), all patients showed return of motor and sensory function, as tested by ankle dorsiflexion and dorsal foot sensation, with average motor strength of 4.6 of 5.3. Acute decompression of acute CPNP after total knee arthroplasty is a prudent treatment option that provides good functional results and rapid recovery. [Orthopedics. 2021;44(4):e556-e562.].

Clinical Outcomes After Neurolysis for the Treatment of Peroneal Nerve Palsy: A Systematic Review and Meta-Analysis

BACKGROUND

Neurolysis techniques have been adapted for decompression of peripheral nerves in multiple locations, including the common peroneal nerve (CPN) at the fibular neck. The aim of this study was to conduct a systematic review and meta-analysis to summarize the clinical outcomes of neurolysis for the management of peroneal nerve palsy (PNP).

METHODS

Preferred Reporting Systems for Systematic Reviews and Meta-Analyses guidelines were followed for this meta-analysis. Four databases were queried, and randomized clinical trials, cohort studies, case-control studies, and case series with n > 10 published in English that evaluated clinical outcomes of neurolysis for the treatment of PNP and foot drop were included. Two reviewers completed screening and data extraction. Methodological quality was evaluated using the Newcastle-Ottawa Scale.

RESULTS

A total of 493 articles were identified through literature search. Title and abstract screening identified 39 studies for full-text screening. Ten articles met the inclusion criteria for qualitative analysis, and 8 had complete data for meta-analysis.Overall, there were 368 patients (370 nerves) who had neurolysis of the CPN for PNP, of which 59.2% (n = 218) were men and 40.8% (n = 150) were women. The mean age of the patients was 47.1 years (SD, 10.0 years), mean time to surgery was 9.65 months (SD, 6.3 months), and mean follow-up time was 28 months (SD, 14.0 months). The median preoperative Medical Research Council (MRC) score was 1 (IQR 0, 3), with 42.2% (n = 156) having MRC score of 0. The median postoperative MRC score was 5 (IQR 4, 5), with 53.9% (n = 199) having MRC score of 5. Complications of neurolysis of the peroneal nerve for treatment of PNP included postoperative infection (0.54%, n = 2), wound dehiscence (0.27%, n = 1), hematoma (0.54%, n = 2), bleeding (0.27%, n = 1), relapse of PNP (0.27%, n = 1), and 1 case of mortality due to sepsis.

CONCLUSIONS

Our meta-analysis shows that neurolysis of the CPN is safe and improves ankle dorsiflexion strength in patients with PNP. Future studies should use a standardized method of measuring sensory outcomes, and studies of higher levels of evidence are needed to better assess the clinical outcomes of neurolysis for treatment of PNP.

The Addition of a Nerve Transfer to the Treatment of Peroneal Neuropathy Secondary to Intraneural Ganglion: Case Series

ABSTRACT

Peroneal intraneural ganglia are rare, and their management is controversial. Presently, the accepted treatment of intraneural ganglia is decompression and ligation of the articular nerve branch. Although this treatment prevents recurrence of the ganglia, the resultant motor deficit of foot drop in the case of intraneural peroneal ganglia is unsatisfying. Foot drop is classically treated with splinting or tendon transfers to the foot. We have recently published a case report of a peroneal intraneural ganglion treated by transferring a motor nerve branch of flexor hallucis longus into a nerve branch of tibialis anterior muscle in addition to articular nerve branch ligation and decompression of the intraneural ganglion to restore the patient's ability to dorsiflex. We have since performed this procedure on 4 additional patients with appropriate follow-up. Depending on the initial onset of foot drop and time to surgery, nerve transfer from flexor hallucis longus to anterior tibialis nerve branch may be considered as an adjunct to decompression and articular nerve branch ligation for the treatment of symptomatic peroneal intraneural ganglion.

Acute bilateral foot drop with or without cauda equina syndrome-a case series

Introduction

Isolated acute bilateral foot drop due to degenerative spine disease is an extremely rare neurosurgical presentation, whilst the literature is rich with accounts of chronic bilateral foot drop occurring as a sequela of systemic illnesses. We present, to our knowledge, the largest case series of acute bilateral foot drop, with trauma and relevant systemic illness excluded.

Methods

Data from three different centres had been collected at the time of historic treatment, and records were subsequently reviewed retrospectively, documenting the clinical presentation, radiological level of compression, timing of surgery, and degree of neurological recovery.

Results

Seven patients are presented. The mean age at presentation was 52.1 years (range 41–66). All patients but one were male. All had a painful radiculopathic presentation. Relevant discopathy was observed from L2/3 to L5/S1, the commonest level being L3/4. Five were treated within 24 h of presentation, and two within 48 h. Three had concomitant cauda equina syndrome; of these, the first two made a full motor recovery, one by 6 weeks follow-up and the second on the same-day post-op evaluation. Overall, five out of seven cases had full resolution of their ankle dorsiflexion pareses. One patient with 1/5 power has not improved. Another with 1/5 weakness improved to normal on the one side and to 3/5 on the other.

Conclusion

When bilateral foot drop occurs acutely, we encourage the consideration of degenerative spinal disease. Relevant discopathy was observed from L2/3 to L5/S1; aberrant innervation may be at play. Cauda equina syndrome is not necessarily associated with acute bilateral foot drop. The prognosis seems to be pretty good with respect to recovery of the foot drop, especially if partial at presentation and if treated within 48 h.

Ganglion Cysts of the Proximal Tibiofibular Joint: Low Risk of Recurrence After Total Cyst Excision

BACKGROUND

Peroneal nerve neuropathy due to compression from tumors or tumor-like lesions such as ganglion cysts is rare. Few case series have been published and reported local recurrence rates are high, while secondary procedures are frequently employed.

QUESTIONS/PURPOSES

(1) What are the demographics of patients with ganglion cysts of the proximal tibiofibular joint, and what proportion of them present with intraneural cysts and peroneal nerve palsy? (2) What Musculoskeletal Tumor Society (MSTS) scores do patients with this condition achieve after decompression surgery with removal of the ganglion cyst, but no arthrodesis of the tibiofibular joint? (3) What proportion of patients experience local recurrence after surgery?

METHODS

Between 2009 to 2018, 30 patients (29 primary cases) were treated for chronic peroneal palsy or neuropathy due to ganglion cysts of the proximal tibiofibular joint at two tertiary orthopaedic medical centers with total resection of the cystic lesion. MRI with contrast and electromyography (EMG) were performed preoperatively in all patients. The minimum follow-up for this series was 1 year (median 48 months, range 13 to 120); 14% (4 of 29) were lost to follow-up before that time. The MSTS score was recorded preoperatively, at 6 weeks postoperatively, and at most-recent follow-up.

RESULTS

A total of 90% of the patients were male (26 of 29 patients) and the median age was 67 years (range 20 to 76). In all, 17% (5 of 29) were treated due to intraneural ganglia. Twenty-eight percent (8 of 29) presented with complete peroneal palsy (foot drop). The mean MSTS score improved from 67 ± 12% before surgery to 89 ± 12% at 6 weeks postoperative (p < 0.001) and to 92 ± 9% at final follow up (p = 0.003, comparison with 6 weeks postop). All patients improved their scores. A total of 8% (2 of 25 patients) experienced local recurrence after surgery.

CONCLUSION

Ganglion cysts of the proximal tibiofibular joint occurred more often as extraneural lesions in older male patients in this small series. Total excision was associated with improved functional outcome and low risk of neurologic damage and local recurrence, and we did not use any more complex reconstructive procedures. Tendon transfers may be performed simultaneously in older patients to stabilize the ankle joint, while younger patients may recover after decompression alone, although larger randomized studies are needed to confirm our preliminary observations.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Evaluation and Treatment of Foot Drop Using Nerve Transfer Techniques

Foot drop represents a complex pathologic condition, requiring a multidisciplinary approach for appropriate evaluation and treatment. Multiple etiologic factors require recognition before considering invasive/operative intervention. When considering surgical management for the treatment of foot drop, it is first and foremost imperative to establish the cause of the condition. Not all causes resulting in clinical foot drop have surgical options. Establishing a cause allows the provider to more appropriately curtail a multidisciplinary approach to working-up, and ultimately, treating the patient. The authors offer an algorithm for evaluating and treating foot drop conditions associated with lumbar spine radiculopathy and peripheral nerve lesions.

(Cost-)effectiveness of lower extremity nerve decompression surgery in subjects with diabetes: the DeCompression (DECO) trial-study protocol for a randomised controlled trial

INTRODUCTION

The peripheral nerves of patients with diabetes are often pathologically swollen, which results in entrapment at places of anatomical narrowing. This results in nerve dysfunction. Surgical treatment of compression neuropathies in the lower extremities (lower extremity nerve decompression (LEND)) results in relief of symptoms and gain in peripheral nerve function, which may lead to less sensory loss (short term) and less associated detrimental effects including foot ulceration and amputations, and lower costs (long term). The aim of the DeCompression trial is to evaluate the effectiveness and (cost-)effectiveness of surgical decompression of compressed lower extremity nerves (LEND surgery) compared with patients treated with conventional (non-surgical) care.

METHODS AND ANALYSIS

A stratified randomised (1 to 1) controlled trial comparing LEND surgery (intervention) with conventional non-surgical care (control strategy) in subjects with diabetes with problems of neuropathy due to compression neuropathies in the lower extremity. Randomisation is stratified for participating hospital (n=11) and gender. Patients and controls have the same follow-up at 1.5, 3, 6, 9, 12, 18, 24 and 48 months. Participants (n=344) will be recruited in 12 months and enrolled in all affiliated hospitals in which they receive both the intervention or conventional non-surgical care and follow-up. Outcome assessors are blinded to group assignment.

PRIMARY OUTCOME

disease-specific quality of life (Norfolk Quality of Life Questionnaire-Diabetic Neuropathy).

SECONDARY OUTCOMES

health-related quality of life (EuroQoL 5-dimension 5-level (EQ-5D5L), 36-item Short Form (SF-36)), plantar sensation (Rotterdam Diabetic Foot Test Battery), incidence of ulcerations/amputations, resource use and productivity loss (Medical Cost Questionnaire, Productivity Cost Questionnaire) during follow-up. The incremental cost-effectiveness ratio will be estimated on the basis of the collected empirical data and a cost-utility model.

ETHICS AND DISSEMINATION

Ethics approval has been granted by the Medical Research Ethics Committee of Utrecht University Medical Center (reference: NL68312.041.19v5, protocol number: 19-335/M). Dissemination of results will be via journal articles and presentations at national and international conferences.

TRIAL REGISTRATION NUMBER

NetherlandsTrial Registry NL7664.

Isolated Nerve Grafting for a Young Patient with a Complete Common Peroneal Nerve Palsy Following a Traumatic Knee Dislocation: A case report

BACKGROUND

Common peroneal nerve (CPN) injury following a knee dislocation is a serious problem, and an optimal treatment is yet to be established. We report a case of complete CPN palsy following a knee dislocation treated with sural nerve grafting.

CASE

A 19-year-old man suffered a knee injury during a hurdle race. Diagnosis in a previous hospital revealed a complex ligament injury with CPN palsy. Ten weeks following injury, he was admitted to our institution because of a lack of neurological improvement. Considering the grade 0 results obtained in the manual muscle test (MMT) of tibialis anterior (TA) and extensor hallucis longus (EHL), the patient was diagnosed with complete neurotmesis of CPN, and surgery was performed. Operative findings revealed CPN discontinuity and an extended nerve defect length of 15 cm; therefore, sural nerve grafting was performed to repair the CPN injury. One year postoperatively, a grade 1 result from MMT of TA and EHL indicated a gradual neurological recovery. Three years postoperatively, MMT of TA and EHL showed significant improvement to grade 4+ and grade 4, respectively, and he could walk and jog without a knee brace.

DISCUSSION

Nerve graft length of >6 cm has shown limited success, and their efficacy for the treatment of CPN palsy following knee dislocations is controversial. However, young patients with complete CPN lesion are more likely to recover regardless of the length of nerve injury. Therefore, in such cases, nerve grafting can be considered as one of the treatments for complete CPN lesion following knee dislocations.

[Tendon transfer as a treatment modality of peroneal nerve palsy]

This review summaries the knowledge of the treatment of peroneal nerve palsy. Isolated peroneal nerve palsy is often seen after fracture of the knee or knee dislocation. In cases with chronic peroneal nerve palsy and foot drop, tendon transfer of the posterior tibial muscle tendon to the dorsum of the foot is a possibility to be considered. This procedure is indicated for isolated peroneal nerve palsy with good ankle mobility, good strength of the posterior tibial muscle and no chance of spontaneous remission.

Resolution of Preoperative Peroneal Nerve Palsy After Total Knee Arthroplasty: A Case Report

CASE

We present the case of a 71-year-old man with right knee osteoarthritis (OA) and a varus deformity who developed a progressive common peroneal nerve palsy that resolved after total knee arthroplasty (TKA). After decades of knee pain, the patient gradually developed a foot drop as well as numbness and paresthesias over the foot dorsum during the course of 1 month. The patient underwent TKA and within 6 weeks postoperatively had complete resolution of the peroneal nerve symptoms.

CONCLUSION

A progressive common peroneal palsy in advanced varus knee OA may resolve after a properly aligned TKA without nerve decompression.

Prognosis for Recovery of Foot Drop after Transforaminal Endoscopic Decompression of Far Lateral Lumbar 5-Sacral 1 Herniated Disc: Case Series

BACKGROUND

Foot drop that results from compression of the exiting L5 nerve as a result of far lateral disc herniation (FLDH) at L5-S1 poses a significant surgical challenge to the minimally-invasive spine surgeon given the narrow corridor for an extraforaminal approach because of the high iliac crest.

OBJECTIVES

Here we describe our experience with transforaminal endoscopic decompression for the treatment of foot drop secondary to FLDH at L5-S1.

STUDY DESIGN

Retrospective case review.

SETTING

This study took place in a single-center, academic hospital.

METHODS

A technique for the transforaminal endoscopic treatment of foot drop secondary to L5-S1 FLDH is presented in a series of 5 consecutive patients treated over a period of 3 years. Preoperative and postoperative clinical data with 1-year follow-up are presented.

RESULTS

A consecutive series of 211 patients who underwent transforaminal endoscopic treatment for lumbar radiculopathy between 2011 and 2014 are presented. Seventy-seven patients had L5-S1 discectomies and 5 of those patients presented with foot drop and FLDH. The mean visual analog scale score for radicular pain improved from an average pain score before surgery of 7.2 to 0.8 one year after surgery, and the mean motor score for anterior tibialis strength improved from an average motor score before surgery of 2.6 to 4.8 one year after surgery.

LIMITATIONS

Small case series evaluated retrospectively with one year follow-up.

CONCLUSIONS

Transforaminal endoscopic surgical access to FLDH pathology may be a unique approach to the treatment of foot drop because it allows for neural decompression of disc and foraminal pathology without requiring significant destabilizing bone removal.

KEY WORDS

Endoscopic spine surgery, minimally-invasive, transforaminal, foot drop, far lateral disc herniation.

[Peroneal Nerve Palsy Management by Tibialis Posterior Muscle Transposition - Anatomical and Clinical Study]

PURPOSE OF THE STUDY Transposition of tibialis posterior muscle ranks among the methods of dorsiflexion restoration in patients with peroneal nerve palsy. Even though this method is commonly used, anatomical variations are still encountered which make us modify the established procedures. The purpose of this study is to evaluate the functional outcomes of operated patients and based on the clinical experience to define by cadaver preparation the anatomical causes preventing the use of the standard transposition technique. MATERIAL AND METHODS The clinical group includes 21 patients (15 men, 6 women) with the mean age of 34.2 years and with common peroneal nerve palsy confirmed by EMG. In 20 patients, transposition of the tendon of the tibialis posterior muscle (MTP) through the interosseous membrane of the leg was performed. In one patient the tendon was transposed ventrally to the distal end of the tibia and fixed in the lateral cuneiform bone due to an extremely narrow space of the interosseous membrane of the leg distally between the lower limb bones. In 18 patients the tendon was fixed by osteosuture to the base of 3rd metatarsal bone, in three patients to the lateral cuneiform bone. The outcomes were evaluated at 6 months after the surgery, when active ankle dorsiflexion (DF) range of motion greater than 5° was considered an excellent outcome, active position at 90° up to DF less than 5° a satisfactory outcome, and any plantigrade position as a poor outcome. The anatomical study included 20 extremities fixed by formalin (10 cadavers, 5 men and 5 women with the mean age of 71.3 years). The length of the individual parts of tibialis posterior muscle was measured and the variations of the muscle attachment were evaluated. The measurement was concluded by a simulation of surgical procedure. RESULTS When evaluating the clinical group, an excellent outcome was reported in 12 patients (57%), a satisfactory outcome in 8 patients (38%) and a poor outcome in one patient (5%). When evaluating the anatomical group, a division of the attaching part of the tendon into three main strips was observed. The thickest middle strip attached to the tuberosity of navicular bone and medial cuneiform bone was reported in all the specimens. The thinner lateral strip (originating from the tendon in 90% of specimens) was attached to the intermediate and lateral cuneiform bone, the cuboid bone, metatarsal bones II-V, and moreover it grows into the origin of the flexor hallucis brevis muscle. The third strip of the tendon attached to the sustentaculum tali, plantar calcaneonavicular ligament and fibrocartilago navicularis was missing in one specimen (5%). When the passing the tendon through the interosseous space between the lower limb bones was simulated in order for the tendon to go in the direction of the planned traction, in two specimens (10%) the pulling through was impossible due to the tendon being thicker than the interosseous space. In two specimens (10%) it was not the tendon, but already the muscular belly which passed through the given space. DISCUSSION In our group, 95% of the functional outcomes were excellent or satisfactory. A poor result was reported in one patient, in whom the EMG examination was not performed as a standard procedure and in whom the muscular strength was insufficient to achieve full dorsiflexion of the ankle. The anatomical study indicates that the narrow space between the lower limb bones can prevent the pulling through of the tendon, which can be addressed intraoperatively by the transposition of the tendon ventrally to tibia. The study reveals that the tendon necessary for transposition can be elongated by the strips of the tendon attached to the sole of the foot. CONCLUSIONS The knowledge of the anatomical conditions may help us better manage potential complications intraoperatively. Key words: tibialis posterior muscle, peroneal nerve palsy, transposition of tibialis posterior muscle, anatomy of tibialis posterior muscle, common fibular nerve palsy.

External neurolysis as a treatment for foot drop secondary to weight loss: a retrospective analysis of 200 cases

BACKGROUND

Peroneal nerve entrapment is the most common peripheral mononeuropathy of the lower limbs. Foot drop, a common presentation, leads to an impaired eversion and dorsiflexion of the foot. An intriguing observation is the occurrence of foot drop secondary to weight loss.

METHODS

A retrospective study of patients surgically treated for peroneal nerve entrapment was performed between January 1, 1995 and December 31, 2016, at the Department of Neurosurgery, Genk, Belgium. Out of a total of 421 patients, 200 patients with foot drop secondary to weight loss were included. For each subject, motor and sensory outcomes after external neurolysis were investigated. As a primary objective, we examined the postoperative outcomes of external neurolysis as a treatment for foot drop in patients with peroneal nerve entrapment at the fibular head secondary to weight loss. As a secondary objective, we analyzed the correlation between patient characteristics and the success rate of external neurolysis.

RESULTS

When defining success as a postoperative MRC score of 4 or 5, external neurolysis has a success rate of 85% in patients with foot drop secondary to weight loss. A significant difference (P = < 0.0001) between postoperative and preoperative MRC scores indicates that external neurolysis leads to significant improvement of motor function in patients with foot drop secondary to weight loss. A multiple logistic regression model showed that "preoperative MRC scores" and "duration of symptoms" were the only variables with an impact on postoperative MRC scores. Other variables such as "age," "gender," and "side of entrapment" had no significant impact on postoperative results.

CONCLUSIONS

Statistical analysis emphasizes the important role of external neurolysis in the treatment of peripheral peroneal nerve entrapment. Therefore, external neurolysis at the fibular head should be regarded as a very effective and safe procedure in patients with foot drop secondary to weight loss.

Biomechanical Evaluation of Circumtibial and Transmembranous Routes for Posterior Tibial Tendon Transfer for Dropfoot

BACKGROUND

Tibialis posterior tendon transfer is performed when loss of dorsiflexion has to be compensated. We evaluated the circumtibial (CT), above-retinaculum transmembranous (TMAR), and under-retinaculum transmembranous (TMUR) transfer gliding resistance and foot kinematics in a cadaveric foot model during ankle range of motion (ROM).

METHODS

Eight cadaveric foot-ankle distal tibia specimens were dissected free of soft tissues on the proximal end, applying an equivalent force to 50% of the stance phase to every tendon, except for the Achilles tendon. Dorsiflexion was tested with all of the tibialis posterior tendon transfer methods (CT, TMAR, and TMUR) using a tension tensile machine. A 10-repetition cycle of dorsiflexion and plantarflexion was performed for each transfer. Foot motion and the force needed to achieve dorsiflexion were recorded.

RESULTS

The CT transfer showed the highest gliding resistance ( P < .01). Regarding kinematics, all transfers decreased ankle ROM, with the CT transfer being the condition with less dorsiflexion compared with the control group (6.8 vs 15 degrees, P < .05). TMUR transfer did perform better than TMAR with regard to ankle dorsiflexion, but no difference was shown in gliding resistance. The CT produced a supination moment on the forefoot.

CONCLUSION

The CT transfer had the highest tendon gliding resistance, achieved less dorsiflexion and had a supination moment. Clinical Relevance We suggest that the transmembranous tibialis posterior tendon transfer should be the transfer of choice. The potential bowstringing effect when performing a tibialis posterior tendon transfer subcutaneously (TMAR) could be avoided if the transfer is routed under the retinaculum, without significant compromise of the final function and even with a possible better ankle range of motion.

Compression neuropathy of common peroneal nerve caused by a popliteal cyst: A case report

RATIONALE

Popliteal cyst developing in the sheath of a peripheral nerve or joint capsule may cause compression neuropathy. Although popliteal cyst is very common lesion, it seldom causes serious complications. Common peroneal nerve compression is rarely caused by an extraneural popliteal cyst.

PATIENT CONCERNS

We presented the case of a 52-year-old female with common peroneal nerve compression caused by an extraneural popliteal cyst.

DIAGNOSES

Electromyography showed the damage of common peroneal nerve. MRI magnetic resonance imaging showed the lump to be a popliteal cyst. She was diagnosed as peroneal nerve injury and popliteal cyst.

INTERVENTIONS

The patient was performed peroneal nerve decompression and popliteal cyst excision surgery. We excised the cyst completely and soluted the common peroneal nerve thoroughly. The cyst was filled with thick mucinous material.

OUTCOMES

The pathological report showed that the excised mass was a popliteal cyst. There were no postoperative complications. Pain and hypoesthesia resolved 6 months after surgery.

LESSONS

In this case, compression of the common peroneal nerve was due to an extraneural popliteal cyst, a situation rarely encountered. MRI can show in better detail their size and internal contents as well as their relation with surrounding anatomic structures. Patients with nerve entrapment caused by enlarged or ruptured cysts must be microsurgically excised if symptomatic.

Dynamic factors involved in common peroneal nerve entrapment neuropathy

BACKGROUND

Common peroneal nerve (CPN) entrapment neuropathy (CPNEN) is the most common peripheral neuropathy of the lower extremities. The pathological mechanisms underlying CPNEN remain unclear. We sought to identify dynamic factors involved in CPNEN by directly measuring the CPN pressure during stepwise CPNEN surgery.

METHODS

We enrolled seven patients whose CPNEN improved significantly after CPN neurolysis. All suffered intermittent claudication, and the repetitive plantar flexion test, used as a CPNEN provocation test, was positive. During decompression surgery we directly measured the CPN pressure during several decompression steps.

RESULTS

Before CPN decompression, plantar flexion elicited a statistically significant increase in the CPN pressure (from 1.8 to 37.3, p < 0.05), as did plantar extension (from 1.8 to 23.1, p < 0.05). The CPN pressure gradually decreased during step-by-step surgery; it was lowest after resection of the peroneus longus muscle (PLM) fascia.

CONCLUSIONS

Dynamic factors affect idiopathic CPNEN. The CPN pressure decreased at each surgical decompression step, and removal of the PLM fascia resulted in adequate decompression of the CPN. Our findings shed light on the etiology of idiopathic CPNEN and recommend adequate CPNEN decompression procedures.

Flexor Hallucis Longus Transfer for Foot Drop without Functioning Tibialis Posterior

For a foot drop resulting from peroneal nerve palsy transferring the tibialis posterior tendon is a standard surgical treatment. The situation of foot drop with no functioning tibialis posterior presents a challenge. We describe a case of successful flexor hallucis longus transfer in such a case. Key words: foot drop, flexor hallucis longus, peroneal nerve palsy; tendon transfer.

Permanent Motor Function Loss by Delayed Treatment of Peroneal Intraneural Ganglion

The low incidence of intraneural ganglion makes it difficult to diagnose and treat before it becomes serious nerve damage. This case describes a 69-year-old female, who suffered from the right drop foot and was diagnosed as a peroneal intraneural ganglion. Resection of the mass relieved the pain; however, motor function was not recovered. Early diagnosis and nerve decompression are essential for the peroneal intraneural ganglion before critical nerve symptoms.

Foot and Ankle Kinematics and Dynamic Electromyography: Quantitative Analysis of Recovery From Peroneal Neuropathy in a Professional Football Player

The assessment of neuromuscular recovery after peripheral nerve surgery has typically been a subjective physical examination. The purpose of this report was to assess the value of gait analysis in documenting recovery quantitatively. A professional football player underwent gait analysis before and after surgery for a peroneal intraneural ganglion cyst causing a left-sided foot drop. Surface electromyography (SEMG) recording from surface electrodes and motion parameter acquisition from a computerized motion capture system consisting of 10 infrared cameras were performed simultaneously. A comparison between SEMG recordings before and after surgery showed a progression from disorganized activation in the left tibialis anterior and peroneus longus muscles to temporally appropriate activation for the phase of the gait cycle. Kinematic analysis of ankle motion planes showed resolution from a complete foot drop preoperatively to phase-appropriate dorsiflexion postoperatively. Gait analysis with dynamic SEMG and motion capture complements physical examination when assessing postoperative recovery in athletes.

A Unique Case of Common Peroneal Nerve Entrapment

The authors present a case of a previously healthy 36-year-old man with a 3-day history of spontaneous complete right lower extremity foot drop. He noticed the symptoms immediately when he attempted to stand after waking from sleep. The patient had no history of similar symptoms, recent trauma, or peripheral nerve disease. Physical examination showed a slap foot gait, complete numbness of the lateral leg and dorsal foot, and 0/5 strength with ankle and great toe dorsiflexion and ankle eversion. Serum laboratory studies showed normal values. Nerve conduction studies confirmed increased latency and decreased amplitude of the right peroneal nerve at the knee, whereas electromyography showed denervation of the tibialis anterior and extensor digitorum brevis. Anteroposterior and lateral radiographs showed a normal right knee with the exception of a posterior fibular neck exostosis. Physical therapy, an ankle-foot orthosis, and a 5-day course of oral prednisone burst (50 mg) were prescribed. After 1 month of therapy without resolution, the patient underwent surgical release of the common peroneal nerve and excision of the bony prominence. Twelve days postoperatively, the patient had no sensory improvements but had improved findings on motor examination. Three months postoperatively, the patient had near-normal sensation to light touch in the superficial and deep peroneal nerves, with 5/5 strength and a normal gait. The patient returned to all activity without limitations. The authors present this unique case describing a fibro-osseous source of common peroneal compressive neuropathy and review the literature for spontaneous peroneal entrapment, highlighting the importance of prompt diagnosis and treatment.

Peroneal intraneural ganglion cysts at the fibular neck: the layered "U" surgical approach to the articular branch and superior tibiofibular joint

BACKGROUND

Intraneural ganglia most commonly occur within the peroneal nerve near the fibular neck. Disconnection of the articular branch is required in their treatment. Surgical intervention can be challenging because of unfamiliarity with the region or scarring from previous surgery.

METHOD

We present the layered "U" technique for peroneal intraneural ganglia with clinical examples. Dissection is carried down in parallel to the U-shaped course of the articular branch to provide optimal visualization and avoid injury to major branches of the nerve.

CONCLUSION

This pathoanatomic approach provides direct and safe exposure of the articular branch of the common peroneal nerve.

[Nerve sonography of intraneural ganglia as cause painful peroneal palsies: a case series]

In selected cases acquired peroneal palsy is caused by intraneural ganglia. In contrast to the much more frequent "loco typico" lesion which is caused by external pressure, intraneural ganglia can be treated by microscopic nerve surgery as part of primary treatment strategy. A careful clinical history as well as a profound clinical and electrophysiological examination is required to disclose unusual findings. These are common in non-typical peroneal palsy. In this situation high resolution nerve sonography is a fast and sensitive method to detect intraneural ganglia. We report a case series of three patients with peroneal palsy caused by intraneural ganglia and give a review of the literature.

Peroneal and tibial intraneural ganglion cysts in children

BACKGROUND/AIMS

Intraneural ganglion cyst is a rare and underrecognized clinical entity in the pediatric population, which may cause pain as well as motor and sensory neurological deficits. This study presents 4 pediatric patients harboring ganglion cysts involving the peroneal and tibial nerves.

METHODS

Data encompassing pre- and postoperative analyses of 4 pediatric patients with intraneural ganglion cyst was evaluated.

RESULTS

Out of these 4 patients, 3 had an intraneural ganglion cyst involving the peroneal nerve, and 1 patient had his tibial nerve involved. Two patients were operated for recurrent ganglion cysts with severe postoperative neurological deficits, after preceding operations in other institutions. The other 2 patients had no history of previous surgery, and they had their initial surgical treatment in our institute for primarily diagnosed ganglion cysts. With a mean follow-up of 24 months, all patients experienced pain relief. Significant improvement of motor deficits was achieved in 3 patients. No recurrences were encountered during the 24-month follow-up.

CONCLUSION

Intraneural ganglion cysts in children can be treated with excellent outcome in experienced and dedicated centers, which specialize in peripheral nerve microsurgery.

Hybrid conducting polymer-hydrogel conduits for axonal growth and neural tissue engineering

Successfully and efficiently bridging peripheral nerve gaps without the use of autografts is a substantial clinical advance for peripheral nerve reconstructions. Novel templating methods for the fabrication of conductive hydrogel guidance channels for axonal regeneration are designed and developed. PEDOT is electrodeposited inside the lumen to create fully coated-PEDOT agarose conduits and partially coated-PEDOT agarose conduits.

[Restoration of active foot extension following peroneal nerve palsy]

INTRODUCTION

Common peroneal nerve palsy is the commonest lower extremity peripheral paresis. The foot drop and inability or difficulty to move the ankle and toes dorsally and inability to perform foot pronation is a debilitating condition for the patient. Tendon transfer is a treatment option often used to restore the foot function after the peroneal palsy in cases when reinervation is not clinically satisfactory.

MATERIAL AND METHODS

The study group included 14 patients treated in the Trauma department of FNO either for common or deep peroneal nerve paresis, or for isolated lesion of the anterior tibial muscle. Active muscles, i.e.the posterior tibial muscle (13 patients) or long peroneal muscle (1 patient) were used for the movement restoration procedure. The tendons were anchored to the cuneiform bone.

RESULTS

In all the patients, active foot extension was restored, with the average range of motion of 12.3 degrees (4-20) and with sufficient muscle strength. Based on the Stanmore score assessment, the subjects showed good results, reaching 87-100 points.

CONCLUSION

The posterior tibial muscle tendon transfer, or peroneus longus muscle tendon transfer lead to restoration of active extension of the foot. The reconstruction procedure results in a minor restriction of the ankle range of motion. Considering the foot functionality, it is better to perform the transfer with a slight preload of the tendon, in order to achieve adequate postoperative ankle extension.

Common peroneal nerve palsy associated with pseudotumour after total knee arthroplasty

Pseudotumours about the hip as a result of metal-on-metal wear debris are now widely reported. Nerve palsies associated with such lesions are less commonly described. To our knowledge no previous reports exist which describe pseudotumours about a total knee arthroplasty. The case of a metal-on-metal debris-induced pseudotumour about a total knee arthroplasty with an associated common peroneal nerve palsy is presented. The use of serum ion levels is discussed, specifically for the early detection and diagnosis of full-thickness polyethylene liner wear and subsequent revision options.

Tendon transfers for drop foot correction: long-term results including quality of life assessment, and dynamometric and pedobarographic measurements

BACKGROUND

Drop foot deformity is a common problem with severe restrictions in quality of life and impairment of daily activities. A technique of posterior tibial tendon transfer through the interosseus membrane and fixation to the anterior tibial and the long peroneal tendon "Bridle procedure" (stirrup-plasty) offers a physiological alternative to surgical correction.

METHODS

Data of 53 consecutive patients treated by stirrup-plasty were acquired from patient's charts; 31 were interviewed with standardized questionnaires; 20 were examined physically; 19 received pedobarography, and 8 underwent dynamometric muscle function tests. Follow-up time averaged 6.5 years.

RESULTS

The mean range of motion (ROM) in the ankle joint was 8° dorsiflexion and 15° plantar flexion. Most patients achieved plantigrade foot position and the majority developed gait without orthotic devices. As expected, maximum dorsiflexion torque averaged a third of the non-operated leg, according to reduced muscle diameter and strength of the transferred muscle. Pressure distribution of the sole during gait was not relevantly altered by the tendon transfer compared to the non-operated leg. Most patients were satisfied with the operative results and reported a significant increase in quality of life.

CONCLUSIONS

Fusion of the transposed posterior tibial, anterior tibial and the peroneus longus tendon prevents drop foot deformity sufficiently. The stirrup mechanism, in combination with tenodesis of the toe extensors, provides a balanced foot and avoids equinovarus and cavus deformity without immobilizing the ankle joint. Improvements in quality of life parameters justify the risk of the operative procedure for the patient.

Peroneal nerve dysfunction after total knee arthroplasty: characterization and treatment

The purpose of this study was to report on the presentation, evaluation, treatment, and outcome of patients who had a peroneal nerve dysfunction after total knee arthroplasty. Six patients were unable to achieve adequate range of motion after physical therapy, and the remaining 5 patients had sensory symptoms that interfered with daily activities despite adequate range of motion. All 11 patients had abnormal electrodiagnostic testing but had intact motor strength and were treated with surgical decompression of the nerve. The patients with motion problems had a mean increase in range of motion of 40 ° (range, 20 °-70 °) at final follow-up. All patients with dominant sensory symptoms had a resolution of leg and foot pain after treatment. Orthopedic surgeons should be aware of peroneal nerve dysfunction as a possible cause of unsatisfactory rehabilitation and/or persistent atypical lateral leg pain after total knee arthroplasty.

Unrecognized acute exertional compartment syndrome of the leg and treatment

Acute-on-chronic exertional compartment syndrome is rare and may be easily missed without a high degree of awareness and clinical suspicion. We report a case of unrecognized acute-on-chronic exertional compartment syndrome in a recreational soccer player. The late sequela of this condition, foot drop, was successfully treated with transfer of the peroneus longus tendon.

[Peroneal nerve palsy in patient with Ehlers-Danlos syndrome]

Ehlers-Danlos syndrome (EDS) is a hereditary generalized connective tissue disorder characterized by skin hyperextensibility, joint hypermobility and tissue fragility. Peripheral neuropathy is described sporadically. Although the exact mechanism of the neuropathy is not well-known, excessive stretch and abnormal connective tissue support are the suggested causative agents. To our knowledge, total peroneal nerve palsy occurring in conjunction with a growth spurt has not previously been described. We describe the case of a young male patient, who developed a total unilateral peroneal palsy during a growth spurt.

Subcutaneous lipoma compressing the common peroneal nerve and causing palsy: sonographic diagnosis

The compression of peripheral nerves by benign fatty tumors has rarely been reported in the literature. We present the case of a patient who had a subcutaneous lipoma in the region of the knee that caused common peroneal nerve palsy and appeared to compress the nerve on sonography. The surgical removal of subcutaneous lipoma allowed complete recovery.

An unusual cause of paralysis of the peroneal nerve-a case report

A 12-year-old boy was referred to our clinic because of progressive paresis of left peroneal nerve. Ultrasound showed a cystic mass close to the proximity of the fibula neck. Puncture revealed jelly-like fluid, but that could not relieve symptoms. Six weeks after onset of symptoms, the boy had complete paresis. Peroneal intraneural ganglia are a rare entity of paralysis of the lower limb in children; more often these symptoms occur because of exostosis. Surgical exploration showed a cystic formation involving the common peroneal nerve. Total recovery of nerve function was seen two years later. Patients with exostosis showed varying outcomes. In children with symptoms suspicious of nerve compression, fast diagnosis and immediate treatment are mandatory to regain best possible recovery.