Combining reverse end-to-side neurorrhaphy with rapamycin treatment on chronically denervated muscle in rats.

This preliminary research determines whether a combination of reverse end-to-side neurorrhaphy and rapamycin treatment achieves a better functional outcome than a single application after prolonged peripheral nerve injury. We found that the tibial nerve function of the reverse end-to-side + rapamycin group recovered better, with a higher tibial function index value, higher amplitude recovery rate, and shorter latency delay rate (P < 0.05). The reverse end-to-side + rapamycin group better protected the gastrocnemius muscle with more forceful contractility, tetanic tension, and a higher myofibril cross-sectional area (P < 0.05). Combining reverse end-to-side neurorrhaphy with rapamycin treatment is a practical approach to promoting the recovery of chronically denervated muscle atrophy after peripheral nerve injury.

Schwannoma of the plantarmedial aspect of the foot: A case report.

Schwannomas of the common medial plantar nerve branch are rare solitary nerve sheath tumors. Fewer than a dozen cases have since been described in the literature, most of which were initially misdiagnosed as ganglion cysts. The case of a 56-year-old male who developed a painful mass on the plantar medial hallux, misdiagnosed as a ganglion cyst, is presented. After surgical intervention and pathological analysis the patient was diagnosed as having a schwannoma. A schwannoma is a slowly growing neoplasm of Schwann cell origin. It is very rare for a schwannoma to transform into a malignant lesion and usually occurs in individuals between the ages for 20-50. Schwannomas usually have a predilection for the head and upper extremities and is very rare in the foot and ankle. The principal treatment of a schwannoma is surgical excision, which eliminates symptoms and can correctly diagnose the mass. Even though schwannomas of the foot have been reported in literature, this case demonstrates an abnormal location on a branch of the medial plantar nerve. Level of Clinical Evidence: Level 4 of Evidence.

Traumatic neuroma of the posterior tibial nerve due to previous surgery presenting as a massive tumor in the midfoot: A case report.

A case report of traumatic neuroma, a benign non-neoplastic tumor of the posterior tibial nerve is presented. The soft tissue mass in the midfoot region was likely a sequela of previous nerve decompression surgery that the patient underwent five years previously in the same region and on the same nerve. Physical examination and history taking, along with an MRI, were important steps in reaching a definitive diagnosis of traumatic neuroma based on the findings of an interventional radiologist and histopathological evaluation of the biopsy by a pathologist. The lesion was subsequently surgically removed utilizing a multidisciplinary management approach. The patient recovered uneventfully and no symptom recurrence was noted at the 30-month follow-up. The tumor was the largest reported in the literature at the time. This case was also unique in that the patient was relieved of pronation and regained tactile sensation in the midfoot.

Saphenous nerve transfer: A new approach to restore sensation of the sole.

BACKGROUND: Loss of protective sensation of the sole may lead to repeated trauma, chronic nonhealing ulcers, and even amputation. Saphenous nerve (SN) to posterior tibial nerve (PTN) transfer can restore sensation of the sole. METHOD: This study was conducted in a tertiary referral center in Central India. Twenty-one patients (32 feet) diagnosed with loss of sensation of the sole were included in this study. Causes of loss of sensation were Hansen's disease (n = 18), complex sciatic nerve injury (n = 1), lumbosacral spinal tumor (n = 1), and lumbosacral meningomyelocele (n = 1). Seventeen feet (14 patients) had ulcers on the sole. Preoperative and postoperative sensory tests performed on the sole included tests for touch, pain, temperature, pressure, vibration, and two-point discrimination. Results were classified as per the British Medical Research Council (MRC) scoring system. RESULTS: Seventeen patients (26 feet) were available for follow-up at 6 months after surgery. All patients had improvement in sensory parameters. Ulcers completely healed in 13 feet and reduced in size in four feet. MRC score improved from S0 in 22 feet and S1 in 10 feet to S3 + in 20 feet, S3 in four feet, and S2 in two feet. CONCLUSIONS: Sensory neurotization with SN transfer to PTN can restore protective sensation to the sole and help in the healing of ulcers.

A Case of Posterior Tibial Nerve Injury After Arthroscopic Calcaneoplasty.

We report the first case of distal posterior tibial nerve injury after arthroscopic calcaneoplasty. A 59-year-old male had undergone right arthroscopic calcaneoplasty to treat retrocalcaneal bursitis secondary to a Haglund's deformity. The patient complained of numbness in his right foot immediately after the procedure. Two years later and after numerous assessments and investigations, a lateral plantar nerve and medial calcaneal nerve lesion was diagnosed. In the operating room, the presence of an iatrogenic lesion to the distal right lateral plantar nerve (neuroma incontinuity involving 20% of the nerve) and the medial calcaneal nerve (complete avulsion) was confirmed. The tarsal tunnel was decompressed, and both the medial and the lateral plantar nerve were neurolyzed under magnification. To the best of our knowledge, our case report is the first to describe iatrogenic posterior tibial nerve injury after arthroscopic calcaneoplasty. It is significant because this complication can hopefully be avoided in the future with careful planning and creation of arthroscopic ports and treated appropriately with early referral to a nerve specialist if the patient's symptoms do not improve within 3 months.

A rare case of an acute soleus arcade syndrome complicated by a ganglion cyst: diagnosis by dynamic ultrasound.

The soleus arcade syndrome is a rare compression neuropathy of the tibial nerve that often remains undiagnosed due to low clinical awareness and difficult diagnosis. We present the case of a female patient admitted with acute worsening of a pre-existing sensory tibial neuropathy and acute tibial nerve palsy after knee joint injection. After a knee magnetic resonance imaging remained non-diagnostic, dynamic ultrasonography was performed. Constriction by the soleus arcade and proximal swelling of the tibial nerve could be demonstrated during plantarflexion of the ankle by means of a dynamic examination in the standing patient. The patient underwent surgery and recovered fully. This proposed diagnostic approach can be used to identify soleus arcade syndrome by ultrasound.

Radioguided Occult Lesion Localization in Deep Schwannomas of the Peripheral Nerves: Results of a Preliminary Case Series.

BACKGROUND: The detection of small deep schwannomas of the peripheral nerves has been increasing since the the use of precise neuroimaging techniques has become more widespread; however, although nonpalpable lesions can be well defined by images, it is often difficult to identify them during the surgical procedure. The authors report seven cases of nonpalpable small deep schwannomas surgically treated after their identification using the radioguided occult lesion localization (ROLL) technique. METHODS: Seven men, whose ages ranged from 34 to 70 years (mean 52 years), presented with symptomatic nonpalpable peripheral nerve lesions; two cases involved the sciatic nerve, two the femoral nerve, two the radial nerve, and one the tibial nerve. Before the operation, all the patients were studied by ultrasonography and magnetic resonance imaging (MRI); 1 h before the surgery 3-5 MBq of 99mTc labeled with human albumin macroaggregates was injected into the lesion. A gamma detection probe permitted the preoperative and intraoperative detection of the nonpalpable schwannomas. CONCLUSIONS: The ROLL technique provides good support for identifying small lesions of the peripheral nerves both preoperatively and intraoperatively. This technique permits the use of minimally invasive approaches performed with local anesthesia, with good cosmetic results and acceptance by the patients.

A Complication of Posterior Malleolar Fracture Fixation.

We present a case of tibial nerve impingement by an anteroposterior screw inserted for stabilization of a posterior malleolar fracture. This specific complication has not previously been described in published studies, although numerous reports have described various forms of peripheral nerve entrapment. We discuss the merits of fixation of these fractures using a posterolateral approach.

Associated lateral process and posteromedial tubercle talus fractures with entrapment of the medial neurovascular bundle: a case report.

This paper describes a case of an isolated fracture of the lateral process of the talus associated with a fracture in the posteromedial tubercle of the talus with entrapment of the medial neurovascular bundle. Currently no similar cases have been published describing this type of neurovascular bundle injury. Furthermore, in contrast to previously published cases, both fractures were treated surgically despite the absence of posteromedial tubercle fracture displacement. This article reviews the literature and provides useful recommendations for the clinical management of similar cases in the future.

Earthquake generated proximal tibial nerve compression treated by surgery.

PURPOSE: This article reports on nine cases of proximal tibial nerve compression by the soleal tendinous arch caused by unsuitable treatment of acute compartment syndrome (ACS). Also, we report the clinical results of neurolysis and analyse the cause of this special type of neurological compression. METHODS: There were nine extremities in nine patients included in the study. All patients were among the victims of the Wenchuan earthquake in 2008. All patients had a previous lower extremity ACS. Pain level, numbness in the sole, muscle strength of the flexor hallucis longus and Tinel's sign were evaluated pre- and post-operatively. Each proximal tibial nerve compression was subjected to neurolysis with division of the soleal tendinous arch. RESULTS: At a mean follow-up of 22 months, eight patients (87 %) with weakness of the flexor hallucis longus showed improvement in flexor strength and seven patients (78 %) exhibited improved sensory function in the sole. All patients experienced pain relief. Subjective pain was reduced from an average score of 2.7 to 0.7 based on a visual analogue scale. Physical examination for Tinel's sign revealed all patients experienced relief of radiating pain, but two patients still retained a positive Tinel's sign (mild) over the soleal tendinous arch. In summary, four patients were highly satisfied, four were satisfied and one was neither satisfied nor dissatisfied with functional recovery after neurolysis. CONCLUSIONS: Unsuitable treatment of lower extremity ACS can lead to tibial nerve compression beneath the soleal tendinous arch. Neurolysis may improve pain and sensory and motor function.

Surgical treatment of superimposed, lower extremity, peripheral nerve entrapments with diabetic and idiopathic neuropathy.

BACKGROUND: Although it is recognized that people with peripheral neuropathy have an increased prevalence of chronic nerve entrapment, controversy still exists over their management. The present report details the evaluation, surgical approach, and outcome of a large cohort of people with diabetic and with idiopathic neuropathy. METHODS: A retrospective review of 158 consecutive patients, 96 with diabetic and 62 with idiopathic neuropathy, was done to analyze the results of neurolysis of multiple sites of chronic nerve compression in the lower extremity. Of these patients, 50 had a contralateral limb decompressed for a total of 208 limbs included in the study. Outcomes included visual analog scale (VAS) for pain in the 109 patients who had pain level greater than 8.0, measurement of the cutaneous pressure threshold for sensibility, self-reported change in pain medication usage, and self-reported change in balance. RESULTS: With a minimum follow-up of 1 year, 88% of patients with preoperative numbness reported improvement in sensation (P < 0.001). Of the 84 patients with impaired balance, 81% reported improvement in balance. Of those whose VAS was greater than 8, 83% reported an improvement in VAS (P < 0.001). There was a concomitant reduction in pain medication usage. There was no difference in outcomes between patients with diabetic versus idiopathic neuropathy in response to nerve decompression. CONCLUSIONS: Neurolysis of lower extremity chronic nerve compressions in patients with neuropathy and superimposed nerve compressions is an effective method for relieving pain, restoring sensation, and improving balance.

MRI findings in patients with tibial nerve compression near the knee.

The soleus sling has been recently identified as a site of compression of the tibial nerve resulting in tibial neuropathy. Diagnosis of soleal sling syndrome is difficult, and has been based mainly on clinical examination. Advances in MR imaging with high-resolution 3-Tesla scanners have made direct visualization of nerve pathology possible. With the use of high-resolution imaging and fat-suppression protocols, tibial nerve compression at the soleal fascial arch can be demonstrated in a subset of patients presenting with idiopathic tibial neuropathy. The purpose of this paper is to confirm the ability of MR imaging to demonstrate pathologic changes in the tibial nerve in patients presenting with soleal sling syndrome. Additionally, patients presenting with tibial neuropathy and ganglion cysts, both extra- and intraneural, were examined to determine if the site of compression corresponded to the region of the soleus sling. Nine patients were included in the study, two with idiopathic soleus sling syndrome, four with extraneural, and three with intraneural ganglion cysts. In the patients presenting with idiopathic soleus sling syndrome, MR imaging demonstrated a thickened soleus sling with T2 hyperintensity of the tibial nerve at the level of the sling and denervation changes in muscles of the posterior compartment of the leg. In patients with extraneural ganglion cysts, MR imaging demonstrated a "sandwich"-like compression of the tibial nerve between the cyst and the soleus sling with corresponding tibial nerve T2 hyperintensity and denervation change in posterior compartment muscles. No compression of the tibial nerve at the soleus sling was found in the intraneural ganglion population. We conclude that MR imaging is effective in demonstrating pathologic changes in the tibial nerve at the soleus sling. Based on the MRI findings, we also believe that the soleus sling is a component of the compression when patients present with extraneural ganglion cysts and tibial neuropathy near the knee; in these patients, we recommend release of the soleus sling as part of the definitive management.

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.

Tibial nerve decompression: reliable exposure using shorter incisions.

BACKGROUND: Patients and surgeons recognize the value of procedures that minimize scarring and tissue dissection, but technical standards do not exist with regards to incision lengths needed for tibial nerve decompression. This article introduces reproducible techniques that reliably provide exposure for release of known anatomical compression points of the tibial nerve, while minimizing the length of required skin incisions. METHODS: The senior author's approach to decompression of the tibial nerve at the soleus arch and the tarsal tunnel is presented. Typical incision lengths and surgical exposure are demonstrated photographically. The safety of using this technique is examined by review of the medical records of all patients undergoing this procedure from 2003 to 2011, looking for technical complications such as unintentional damage to nerves or adjacent structures. RESULTS: 224 consecutive patients undergoing 252 total procedures underwent release of known anatomical compression points of the tibial nerve at either the tarsal tunnel, inner ankle, or the soleus arch. Typical incision lengths used for these procedures were 5 cm for the proximal calf and 4.5 cm for the tarsal tunnel. Review of medical records revealed no incidences of unintentional injury to nerves or adjacent important structures. Functional and neurological outcomes were not assessed. CONCLUSIONS: Tibial nerve decompression by release of known anatomical compression points can be accomplished safely and effectively via minimized skin incisions using the presented techniques. With appropriate knowledge of anatomy, this can be performed without additional risk of injury to the patient, making classically-described longer incisions unnecessarily morbid.

Efficacy of short-term FK506 administration on accelerating nerve regeneration.

BACKGROUND: The slow rate of nerve regeneration following injury can cause extended muscle denervation, leading to irreversible muscle atrophy, fibrosis, and destruction of motor endplates. The immunosuppressant FK506 (tacrolimus) has been shown to accelerate the rate of nerve regeneration and functional recovery. However, the toxic and immunosuppressive properties of FK506 make it undesirable for long-term use. OBJECTIVE: To take advantage of the regeneration-enhancing effects of FK506 but avoid the potential adverse effects of long-term administration, the current study evaluates and quantifies the efficacy of short-term FK506 treatment in rat models. METHODS: Clinically relevant transection and graft models were evaluated, and walking track analysis (WTA) was used to evaluate functional recovery. FK506 was administered for 5 and 10 days post transection injury and 10 and 20 days post graft injury. Both groups involving a short course were compared with the continuous administration group. RESULTS: In the transection model, FK506 was administered for 5 and 10 days postoperatively. WTA demonstrated that 10 days of FK506 administration was sufficient to reduce functional recovery time by 29% compared with negative controls. In the graft model, FK506 was administered for 10 and 20 days postoperatively. Short treatment courses of 10 and 20 days reduced recovery time by 15% and 21%, respectively, compared with negative controls. Analysis of blood-nerve barrier (BNB) integrity demonstrated that FK506 facilitated early reconstitution of the BNB. CONCLUSIONS: The results of this study indicate that short-term FK506 delivery following nerve injury imparts a significant therapeutic effect.

Comparing partial and total tibial-nerve axotomy: long-term effects on prevalence and location of evoked pain behaviors.

Monophasic (one-time) nerve injuries heal without clinically significant residua in most cases, but rare individuals are left with neuropathic pain, even after seemingly minor lesions. The effects of lesion size on risk for chronic pain persistence are not well understood, particularly as concerns the complex regional pain syndrome, which is defined in part by pain "disproportionate" to the severity of the causative lesion, and extending outside the autonomous territory of a single nerve. To better clarify the expected prevalence of pain behaviors after nerve injury, we compared the effects in rats of different-sized axotomies on the prevalence and location of evoked pain behaviors. To highlight clinical relevance, we also describe a patient with iatrogenic tibial-nerve injury causing similar chronic neuralgia. Adult male Sprague-Dawley rats were anesthetized and had either 1/3, 2/3 or their entire left tibial nerves tightly ligated at two sites just below the sciatic trifurcation and the interposed nerve was cut. Unoperated rats provided controls. Sensory function in the tibial and sural-innervated territories of both plantar hindpaws was assessed for as long as 6 months postoperatively. Soon after surgery, evoked pain behavior developed in the ipsilesional sural-innervated site in a subset of axotomized rats and recovery was variable. The relationship between lesion size and prevalence and severity of hyperalgesia varied for different pain behaviors, with pinprick hyperalgesia clearly more likely after larger axotomies. In summary, partial tibial-nerve injury in rats models human disease and suggests that expectations of proportionality between lesion size and development of neuropathic pain may need revision.

[Release of the lateral plantar nerve in case of entrapment]. / Neurolyse des Nervus plantaris lateralis zur Behandlung des Nervenengpasssyndroms am Rückfuss.

OBJECTIVE: Reduction of heel pain by neurolysis of the lateral plantar nerve. Indications Contraindications Surgical Technique Postoperative Management Results INDICATIONS: Heel pain due to an entrapment of the lateral plantar nerve. CONTRAINDICATIONS: Acute inflammatory alterations in the foot. Skin laceration at the medial hindfoot. Relative: heel pain, which could not be assigned to a distinct diagnosis. Relative: flatfoot deformity with hindfoot valgus. SURGICAL TECHNIQUE: Regional anesthesia. Supine position. Tourniquet. Curved skin incision behind the medial malleolus to the medioplantar aspect of the heel. Incision of the flexor retinaculum and careful dissection of the tibial nerve, until the medial and lateral plantar nerves can be clearly identified. Stepwise decompression of the lateral plantar nerve along its course to the medial aspect of the heel. Exposure of the first branch of the lateral plantar nerve (Baxter's nerve) by dissection of the fascia overlying the quadratus plantae muscle and the flexor digitorum brevis muscle. Release of the tourniquet and hemostasis. Wound closure in layers. Below-knee splint in neutral position of the ankle. POSTOPERATIVE MANAGEMENT: Elevation of the concerned leg. Mobilization without weight bearing during the first 5 days. Stepwise increased weight bearing according to the pain level. Soft insoles for 12 weeks. No running or jumping for 12 weeks. RESULTS: From 2006 to 2008, twelve patients (ten women, two men) were treated with a neurolysis of the lateral plantar nerve. In nine patients, the diagnosis was confirmed neurologically; in three patients, the authors decided to perform the nerve decompression due to clinical findings. The patients were followed up clinically (mean follow-up 15 months) and were asked to estimate their pain level with the visual analog scale (VAS). There were no postoperative complications. One patient developed a complex regional pain syndrome. Pain level decreased significantly within 6 weeks (VAS preoperatively 7.9; VAS postoperatively 3.8) and showed a further pain reduction to VAS 2.1 after 9 months. Two patients complained of recurrent symptoms after a mean of 11 months. In these patients, the initial diagnosis could not be confirmed by electrophysiological measurements.