Neuro-orthopaedic Surgery in the Treatment of the Spastic Equinovarus Foot

INTRODUCTION

Stroke is the third cause of death and the leading cause of handicap among industrialized countries (1). Spasticity following stroke is responsible for spastic equinovarus foot (SEF) in 18% of cases (2). Spastic equinovarus foot is due to spasticity (muscle hypertonia) of the calf muscles (soleus, gastrocnemius and tibialis posterior), often complicated by contracture and by the weakness of peroneus longus and peroneus brevis muscles (3). Therefore, stroke patients walk slowly, and often require assistive device as orthosis or canes. This disability limits their social participation and their quality of life.

Spastic equinovarus foot treatments include oral medications, physical therapy, orthosis, chemical denervations (botulinum toxin, alcohol or phenol injections), selective neurotomy and orthopedic surgery (3). Selective neurotomy is a neurosurgical procedure consisting in partially and selectively cutting motor branches innervating the spastic muscles providing a permanent treatment of the spasticity (3). Orthopaedic surgery consists in Achilles tendon lengthening and tibialis anterior transfer (3). The efficacy of mixed neur-orthopaedic surgery has never been prospectively assess according to the ICF classification.

OBJECTIVES

The aim of the present project is to study the effectiveness of neuro-orthopaedic surgery (neurotomy and tendon surgery) in the treatment of SEF.

The functional assessment will explore the three ICF domains.

METHODS

The investigators will recruit 50 chronic spastic patients presenting with SEF. The surgical treatment will be decided according to the improvement obtained by an anaesthetic diagnostic tibial motor nerve branches block (5) followed by an interdisciplinary discussion.

Patients will be assessed before treatment, 2 months, 1 year and 2 years after treatment among the 3 ICF domains. Impairments will be assessed by the Stoke Impairment Assessment Set (SIAS), the Ashworth and Tardieu scales (spasticity) and the MRC scale (muscle strength). Gait disorders will be evaluated by a video analysis. Disability will be evaluated by the ABILOCO scale (6) and the participation (quality of life) by the SATIS-Stroke questionnaire (7) and the SF-36 questionnaire.

The patients selection, the lidocaine hyperselective diagnostic blocks, the selective neurotomy and the tendon surgery will be achieved by the medical doctors participants to the spasticity group. The functional assessment will be achieved by the physical therapists of the PMR department (blinded assessor).

PERSPECTIVE

The investigators hope to demonstrate the benefit of neuro-orthopaedic surgery in case of SEF according to the 3 domains of the ICF (8)

Inclusion criteria

• central neurological disease lasting from more than 6 months
• spastic equinovarus foot due to spasticity and/or contracture
• patient able to walk barefoot
• insufficient benefit from physical therapy and/or orthosis

Exclusion criteria

• pregnant women
• botulinum toxin injection in the last 4 months
• previous surgery for SEF