Cerebral correlates of muscle tone fluctuations in restless legs syndrome: A pilot study with combined functional magnetic resonance imaging and anterior tibial muscle electromyography

BACKGROUND: The pathology of restless legs syndrome (RLS) is still not understood. To investigate the pathomechanism of the disorder further we recorded a surface electromyogram (EMG) of the anterior tibial muscle during functional magnetic resonance imaging (fMRI) in patients with idiopathic RLS. METHODS: Seven subjects with moderate to severe RLS were investigated in the present pilot study. Patients were lying supine in the scanner for over 50min and were instructed not to move voluntarily. Sensory leg discomfort (SLD) was evaluated on a 10-point Likert scale. For brain image analysis, an algorithm for the calculation of tonic EMG values was developed. RESULTS: We found a negative correlation of tonic EMG and SLD (p <0.01). This finding provides evidence for the clinical experience that RLS-related subjective leg discomfort increases during muscle relaxation at rest. In the fMRI analysis, the tonic EMG was associated with activation in motor and somatosensory pathways and also in some regions that are not primarily related to motor or somatosensory functions. CONCLUSIONS: By using a newly developed algorithm for the investigation of muscle tone-related changes in cerebral activity, we identified structures that are potentially involved in RLS pathology. Our method, with some modification, may also be suitable for the investigation of phasic muscle activity that occurs during periodic leg movements.

Neurotized lateral gastrocnemius muscle transfer for persistent traumatic peroneal nerve palsy: Surgical technique

INTRODUCTION Persistent traumatic peroneal nerve palsy, following nerve surgery failure, is usually treated by tendon transfer or more recently by tibial nerve transfer. However, when there is destruction of the tibial anterior muscle, an isolated nerve transfer is not possible. In this article, we present the key steps and surgical tips for the Ninkovic procedure including transposition of the neurotized lateral gastrocnemius muscle with the aim of restoring active voluntary dorsiflexion. SURGICAL TECHNIQUE The transposition of the lateral head of the gastrocnemius muscle to the tendons of the anterior tibial muscle group, with simultaneous transposition of the intact proximal end of the deep peroneal nerve to the tibial nerve of the gastrocnemius muscle by microsurgical neurorrhaphy is performed in one stage. It includes 10 key steps which are described in this article. Since 1994, three clinical series have highlighted the advantages of this technique. Functional and subjective results are discussed. We review the indications and limitations of the technique. CONCLUSION Early clinical results after neurotized lateral gastrocnemius muscle transfer appear excellent; however, they still need to be compared with conventional tendon transfer procedures. Clinical studies are likely to be conducted in this area largely due to the frequency of persistant peroneal nerve palsy and the limitations of functional options in cases of longstanding peripheral nerve palsy, anterior tibial muscle atrophy or destruction.

Nerve Transfers for Persistent Traumatic Peroneal Nerve Palsy: The Inselspital Bern Experience

BACKGROUND Patients in whom conventional peroneal nerve repair surgery failed to reconstitute useful foot lift need to be evaluated for their suitability to undergo a concomitant tendon transfer procedure or nerve transfers. OBJECTIVE To report our first clinical experience with nerve transfers for persistent traumatic peroneal nerve palsy. METHODS Between 2007 and 2013, 8 patients were operated on for foot drop after unsuccessful nerve surgery. Six patients without fatty degeneration of the anterior tibial muscle and proximal lesion of the peroneal nerve were oriented for tibial to peroneal nerve transfer. In the other 2 cases where the anterior and lateral compartments were destructed, the anterior tibial muscle function was reconstructed with a neurotized lateral gastrocnemius transfer. For each patient, we graded postoperative results using the Bureau of Meteorology Research Centre scheme and the Ninkovic assessment scale. RESULTS Of the 6 patients who underwent nerve transfer of the anterior tibial muscle, 2 patients had excellent results, 1 patient had good results, 1 patient had fair results, and 2 patients had poor results. Of the 2 patients that underwent neurotized lateral gastrocnemius transfer, 1 patient achieved excellent results after tenolysis, whereas 1 patient achieved poor results. After the nerve transfer, 5 patients did not wear an ankle-foot orthosis. Four patients did not limp. Four patients were able to walk barefoot, navigate stairs, and participate in activities. CONCLUSION Early clinical results after tibial to peroneal nerve transfer and neurotized lateral gastrocnemius transfer appear mixed. The results of nerve transfer seem, on the whole, less reliable than the literature reports on tendon transfer. ABBREVIATIONS EMG, electromyographyNAP, nerve action potential.

Non-surgical treatment of pain associated with posterior tibial tendon dysfunction: study protocol for a randomised clinical trial

BACKGROUND Symptoms associated with pes planovalgus or flatfeet occur frequently, even though some people with a flatfoot deformity remain asymptomatic. Pes planovalgus is proposed to be associated with foot/ankle pain and poor function. Concurrently, the multifactorial weakness of the tibialis posterior muscle and its tendon can lead to a flattening of the longitudinal arch of the foot. Those affected can experience functional impairment and pain. Less severe cases at an early stage are eligible for non-surgical treatment and foot orthoses are considered to be the first line approach. Furthermore, strengthening of arch and ankle stabilising muscles are thought to contribute to active compensation of the deformity leading to stress relief of soft tissue structures. There is only limited evidence concerning the numerous therapy approaches, and so far, no data are available showing functional benefits that accompany these interventions. METHODS After clinical diagnosis and clarification of inclusion criteria (e.g., age 40-70, current complaint of foot and ankle pain more than three months, posterior tibial tendon dysfunction stage I & II, longitudinal arch flattening verified by radiography), sixty participants with posterior tibial tendon dysfunction associated complaints will be included in the study and will be randomly assigned to one of three different intervention groups: (i) foot orthoses only (FOO), (ii) foot orthoses and eccentric exercise (FOE), or (iii) sham foot orthoses only (FOS). Participants in the FOO and FOE groups will be allocated individualised foot orthoses, the latter combined with eccentric exercise for ankle stabilisation and strengthening of the tibialis posterior muscle. Participants in the FOS group will be allocated sham foot orthoses only. During the intervention period of 12 weeks, all participants will be encouraged to follow an educational program for dosed foot load management (e.g., to stop activity if they experience increasing pain). Functional impairment will be evaluated pre- and post-intervention by the Foot Function Index. Further outcome measures include the Pain Disability Index, Visual Analogue Scale for pain, SF-12, kinematic data from 3D-movement analysis and neuromuscular activity during level and downstairs walking. Measuring outcomes pre- and post-intervention will allow the calculation of intervention effects by 3×3 Analysis of Variance (ANOVA) with repeated measures. DISCUSSION The purpose of this randomised trial is to evaluate the therapeutic benefit of three different non-surgical treatment regimens in participants with posterior tibial tendon dysfunction and accompanying pes planovalgus. Furthermore, the analysis of changes in gait mechanics and neuromuscular control will contribute to an enhanced understanding of functional changes and eventually optimise conservative management strategies for these patients. TRIAL REGISTRATION ClinicalTrials.gov Protocol Registration System: ClinicalTrials.gov ID NCT01839669.