Peroneal and tibial intraneural ganglion cysts in children

Acute Foot Drop Caused by Intraneural Ganglion Cyst of the Peroneal Nerve: Literature Review and Case Report

BACKGROUND

Foot drop (FD) is characterized by an inability to lift the foot against gravity because of dorsiflexor muscle weakness. The aim of the present study is to report a clinical case of acute non-traumatic FD in patients with peroneal intraneural ganglion, after performing a scoping review on the methodological management of this disease.

METHODS

We performed a review of the literature and reported the case of a 49-year-old man with acute FD caused by an intraneural ganglion cyst of the peroneal nerve.

RESULTS

Out of a total of 201 articles, 3 were suitable for our review beyond our case report. The acute FD caused by peroneal intraneural ganglion can be managed by a careful clinical-instrumental differential diagnosis. A targeted surgery with subsequent rehabilitation produced a satisfactory motor recovery.

CONCLUSIONS

Acute FD requires an appropriate diagnostic-therapeutic framework to identify and effectively treat the causes in order to promote complete recovery.

Intraneural Ganglion of the Peroneal Nerve-A Rare Cause of Pediatric Peroneal Nerve Palsy: A Case Report

Intraneural ganglia are benign mucinous cysts located within the epineurium of a peripheral nerve. The pathogenesis and formation of intraneural ganglia are controversial. The main theories described in the literature are of degenerative, synovial or de novo occurrence. We present the case of a 14-year-old boy who presented in our outpatient clinic with a complaint of interdigital neuralgia between hallux and second toe, as well as left foot drop. MRI examination showed a hyperintense cystic distension of the common peroneal nerve measuring 130 mm × 5 mm extending from the poplitea to the anterior compartment of the leg. We performed microscopic decompression and neurolysis surgery. The cyst showed a sac-like distension at its distal end with connection to the tibiofibular joint and was resected. After 8 weeks, postoperatively, the boy claimed to be pain-free and slight recovery of the superficial peroneal nerve was noticed. At 6 months postoperative, the patient showed a continuous improvement of motor function, demonstrating foot eversion with 3/5 muscle strength and foot extension with 2/5 muscle strength. Intraneural ganglia reported for pediatric patients represent a very rare entity. To the best of our knowledge, less than 15 cases have been described within the English-speaking literature.

Treatment approach to isolated common peroneal nerve palsy by mechanism of injury: Systematic review and meta-analysis of individual participants' data

BACKGROUND

We reviewed the individual participant data of patients who sustained isolated common peroneal nerve (CPN) injuries resulting in foot drop. Functional results were compared between eight interventions for CPN palsies to determine step-wise treatment approaches for the underlying mechanisms of nerve injury.

METHODS

PubMed, Embase, Cochrane Library, Web of Science, Scopus, and CINAHL databases were searched. PRISMA-IPD and Cochrane guidelines were followed in the data search. Eligible patients sustained isolated CPN injuries resulting in their foot drop. Patients were stratified by mechanisms of nerve injury, ages, duration of motor symptoms, and nerve defect/zone of injury sizes, and were compared by functional results (poor = 0, fair = 1, good = 2, excellent = 3), using meta-regression between interventions. Interventions evaluated were primary neurorrhaphy, neurolysis, nerve grafts, partial nerve transfer, neuromusculotendinous transfer, tendon transfer, ankle-foot orthosis (AFO), and arthrodesis.

RESULTS

One hundred and forty-four studies included 1284 patients published from 1985 through 2020. Transection/Cut: Excellent functional results following tendon transfer (OR: 126, 95%CI: 6.9, 2279.7, p=0.001), compared to AFO. Rupture/Avulsion: Excellent functional results following tendon transfer (OR: 73985359, 95%CI: 73985359, 73985359, p<0.001), nerve graft (OR: 4465917, 95%CI: 1288542, 15478276, p<0.001), and neuromusculotendinous transfer (OR: 42277348, 95%CI: 3001397, 595514030, p<0.001), compared to AFO. Traction/Stretch: Good functional results following tendon transfer (OR: 4.1, 95%CI: 1.17, 14.38, p=0.028), compared to AFO. Entrapment: Excellent functional results following neurolysis (OR: 4.6, 95%CI: 1.3, 16.6, p=0.019), compared to AFO.

CONCLUSIONS

Functional results may be optimized for treatments by the mechanism of nerve injury. Transection/Cut and Traction/Stretch had the best functional results following tendon transfer. Rupture/Avulsion had the best functional results following tendon transfer, nerve graft, or neuromusculotendinous transfer. Entrapment had the best functional results following neurolysis.

Intraneural ganglion cyst of the common peroneal nerve causing foot drop in a 12-year old child

OBJECTIVES

Intraneural ganglia are benign fluid-filled cysts contained within the subepineurial space of peripheral nerves. The common peroneal nerve at the fibular neck is by far the most frequently involved, although other nerves can be affected as well. Although the differential diagnosis of foot drop in adults and children show some differences, clinical presentation, diagnostic workup, treatment and follow-up of intraneural ganglia are quite similar in both groups. The primary objective was to create an overview of intraneural ganglia in children, with an emphasis on diagnostic workup and potential pitfalls during neurosurgical intervention, based on all available literature concerning this topic and own center experiences. As a secondary objective, we tried to raise the awareness concerning this unique cause of foot drop in childhood.

PATIENTS AND METHODS

We performed a review of the literature, in which children who developed foot drop secondary to an intraneural ganglion cyst of the common peroneal nerve were examined. A total of eleven articles obtained from MEDLINE were included. Search terms included: "pediatric", "children", "child", "intraneural ganglia", "intraneural ganglion cysts", "foot drop", "peroneal nerve" and "fibular nerve". Additional studies were identified by checking reference lists. Furthermore, we present the case of a 12-year old girl with foot drop caused by an intraneural ganglion cyst. She underwent cyst decompression with evacuation of intraneural cyst fluid and articular branch disconnection. PRISMA and CARE statement guidelines were followed.

RESULTS

We hypothesize that minor injury caused a breach in the joint capsule, resulting in synovial fluid egression along the articular nerve branch, corroborating the unifying articular theory and emphasizing the need for ligation of said branch. Foot drop is a predominant characteristic, explained by the proximity of the anterior tibial muscle motor branch near the articular branch nerve. In children, satisfactory motor recovery after surgical decompression is to be expected.

CONCLUSION

Sudden or progressive foot drop in children warrants an exhaustive neurophysiological and radiological workup. The management of intraneural ganglia is specific, consisting of nerve decompression, articular branch ligation and joint disarticulation, if deemed necessary. Our surgical results support the unifying articular theory and emphasize the importance of ligation and transection of the articular branch nerve, distally from the anterior tibial muscle branch, in order to prevent intraneural ganglia recurrence. This well-documented case adds depth to the current literature on this sparsely reported entity.

Intraneural ganglion cysts of the peroneal nerve

BACKGROUND

Intraneural ganglion cysts of the peroneal nerve are rare, and there is lack of evidence for the surgical management of this entity. We performed this study to evaluate the imaging, diagnosis, treatment and outcome of seven patients with intraneural ganglion cysts of the peroneal nerve.

MATERIALS AND METHODS

We retrospectively studied the files of seven patients with intraneural ganglion cysts of the peroneal nerve, diagnosed and treated from 2016 to 2019. Diagnostic approach included clinical examination of the leg and foot, magnetic resonance imaging, nerve conduction studies, surgical excision of the cyst and histological examination. The mean follow-up was 2 years (range 1-3.5 years). We evaluated the time and methods for surgical treatment, and the clinical outcomes of the patients.

RESULTS

All patients presented symptoms of peripheral compression neuropathy; three patients presented with foot drop. The intraneural ganglion cysts were excised in all cases in addition to knee articular nerve branch transection to avoid cysts recurrence. Postoperatively, all patients experienced complete neurological recovery without clinical evidence of intraneural ganglion cysts recurrences.

CONCLUSION

The treating physicians should be aware of intraneural ganglion cysts of the peroneal nerve in patients presenting with limb weakness, sensory deficits at the lateral and anterior side of the leg and foot, paresis or paralysis of the foot and ankle. MR imaging is the imaging modality of choice for a clear and accurate preoperative diagnosis to avoid misdiagnosis and wrong treatment. In case of doubt, these patients should be managed in an orthopedic oncology setting with microsurgery facilities available for complete excision of the intraneural ganglion cyst.

Intraneural Peroneal Ganglion Cyst Excision in a Pediatric Patient: A Case Report

CASE

A 14-year-old female presented with a profound foot drop after trauma to the right leg. Clinical examination and electrodiagnostic studies demonstrated a dense palsy of the common peroneal nerve. Magnetic resonance imaging revealed an intraneural peroneal ganglion cyst at the fibular neck. Surgical treatment included decompression and transection of the articular branch to the proximal tibiofibular joint. At the 1-year follow-up, the patient demonstrated complete recovery of peroneal nerve function.

CONCLUSIONS

This case demonstrates a rare finding of a pediatric intraneural peroneal ganglion cyst. The presentation and treatment is well-documented and adds depth to the literature on a sparsely reported condition.

Recurrent intraneural ganglion cysts: Pathoanatomic patterns and treatment implications

The etiology of intraneural ganglion cysts has been poorly understood. This has resulted in the development of multiple surgical treatment strategies and a high recurrence rate. We sought to analyze these recurrences in order to provide a pathoanatomic explanation and staging classification for intraneural cyst recurrence. An expanded literature search was performed to identify frequencies and patterns in cases of intraneural ganglion cyst recurrences following primary surgery. Two univariate analyses were completed to identify associations between the type of revision surgery and repeat cyst recurrences. The expanded literature search found an 11% recurrence rate following primary surgery, including 64 recurrences following isolated cyst decompression (Group 1); six after articular branch resection (Group 2); and none following surgical procedures that addressed the joint (Group 3). Eight cases did not specify the type of primary surgery. In group 1, forty-eight of the recurrences (75%) were in the parent nerve, three involved only the articular branch, and one travelled along the articular branch in a different distal direction without involving the main parent nerve. In group 2, only one case (17%) recurred/persisted within the parent nerve, one recurred within a persistent articular branch, and one formed within a persistent articular branch and travelled in a different distal direction. Intraneural recurrences most commonly occur following surgical procedures that only target the main parent nerve. We provide proven or theoretical explanations for all identified cases of intraneural recurrences for an occult or persistent articular branch pathway.