Quantitative ultrasound of lower leg and foot muscles: feasibility and reference values.

BACKGROUND: Ultrasound is a non-invasive method to quantitatively measure various muscle parameters. Purpose of this study was to assess the feasibility of ultrasound of lower leg and foot muscles and to obtain reference values for muscle thickness (MT) and echo intensity (EI). METHODS: Ultrasound measurements of leg and foot muscles were performed in 60 healthy adults. MT and EI were quantitatively determined for the abductor hallucis (AH), extensor digitorum brevis (EDB), extensor hallucis longus (EHL) and peroneus longus (PER) muscles. Influence of age, height, weight and sex was determined using a multiple linear regression analysis. RESULTS: All muscles except the AH could easily be visualized with ultrasound. EI tended to be increased above 60 years and MT was significantly higher in men compared to women, necessitating age- and sex-dependent reference values. CONCLUSIONS: This study shows that muscle ultrasound is capable of visualizing lower leg and foot muscles and reference values for MT and EI can be obtained. Future research will focus on the use of these reference values to evaluate muscle abnormalities caused by neuromuscular disorders like hereditary motor and sensory neuropathy.

Flexible cavovarus feet in Charcot-Marie-Tooth disease treated with first ray proximal dorsiflexion osteotomy combined with soft tissue surgery: a short-term to mid-term outcome study.

OBJECTIVES: The purpose of this paper was to retrospectively evaluate the short-term to mid-term results of combined first ray proximal dorsiflexion osteotomy and soft tissue surgery in treatment of pes cavovarus with a fixed plantar flexed first ray and a passively correctable tarsus due to Charcot-Marie-Tooth disease. PATIENTS AND METHODS: Between January 1995 and July 2005, thirty-three patients with pes cavovarus deformity due to Charcot-Marie-Tooth disease were included. All patients had in common that prior to surgery the hindfoot was passively still adequate correctable at the talonavicular joint. The Coleman block test was performed to establish with certainty that hindfoot varus was a secondary deformity. Fourteen patients were male (21 feet) and nineteen were female (31 feet). Mean age at surgery was 28.1 years (range 13-59 years). Mean follow-up time was 56.9 months (range 13-153 months). Evaluation consisted of physical examination of all patients with assessment of early and late complications. The validated Foot Function Index (FFI) was used to measure pain and impairment. Patients' satisfaction was assessed by a Quality of Care Through the Patients' Eyes (QUOTE) questionnaire. INTERVENTION: Surgical correction of cavovarus foot deformity consisted of dorsiflexion osteotomy at the base of the first metatarsal combined with tendon transfers. Secondary calcaneal osteotomy was performed in case of persistent varus of the calcaneus. RESULTS: No major complications were seen. Recurrence of cavovarus deformity in two feet resulted in triple arthrodesis 37 and 64 months postoperatively. The FFI 5-point score for pain improved from a mean 29.3% to a mean 14.8% (p=0.005). The score for disability improved from a mean 37.8% to a mean 23.5% (p<0.001). Patients' satisfaction was assessed by the QUOTE questionnaire. Seventy percent of the patients could walk barefoot after the operation and 77% of the patients had less pain after surgery. Pressure callosities diminished in 81%. Foot function was considered better after surgery by 84%. Ninety percent was satisfied with the correction of the deformity. CONCLUSIONS: First ray dorsiflexion osteotomy combined with tendon transfers is a good and consistent solution to realign the foot and provides short-term to mid-term satisfactory results in 90% of patients with a rigid forefoot cavus deformity due to plantar flexion of the first ray and with a still passively reducible tarsus.