LEG PAIN - MOUNTAIN BIKER

Abstract

2084 HISTORY - A 19 year old national level mountain biker complains of one year of left leg pain in the area of the lateral gastrocnemius muscle. The pain is described as "cramping and pulling" when he is riding. He sometimes has numbness on the sole of the foot. He occasionally awakens at night with severe aching from the knee to the ankle. At times, he is unable to cycle and walking is painful. Pain is aggravated by knee extension. No history of acute injury or trauma, bruising, back pain, posterior thigh pain, or leg edema. No significant past medical history. Training regimen consists of 12 to 20 hrs/ wk cycling, daily stretching, occasional weight lifting. PHYSICAL EXAMINATION - The left leg appears normal without swelling, bruising, or atrophy. Soleus is tender to deep palpation along midline. Tibia and fibula are nontender to palpation and percussion. Anterior compartment muscles are nontender. Achilles tendon intact. Normal ankle range of motion. Straight leg raising test is negative but aggravates leg pain at 90 deg. Knee and ankle jerks 2+ and symmetric. Sensation intact to all modalities. Ankle dorsiflexion and eversion 5/5; plantar flexion and inversion 4+/5; flexor hallucis longus 3/5; extensor hallucis longus 5/5. Strength on the right 5/5 throughout. Gait - antalgic with avoidance of pushoff from left toes. Muscle strain - flexor hallucis longus Nerve injury (tibial or sciatic) or lum bosacral radiculopathy Stress fracture Periostitis Exercise induced compartment syndrome Popliteal artery syndrome Radiographs of L tibia and fibula: Normal. No evidence of fracture or stress reaction. EMG of L leg: Normal. No electrophysiological evidence of lum bosacral radiculopathy or mononeuropathy of the tibial or sciatic nerves. MRI of L leg: Bulbous configuration and edema of flexor hallucis longus muscle. High signal surrounding the tendon, proximal to the tendon sheath. FINAL/WORKING DIAGNOSIS: Flexor hallucis longus muscle strain Relative rest for 3 days (no cycling) Relafen 1500 mg po qd for 2 weeks Stop wearing "flip flop" sandals which require gripping the soles with the toes Use non-clip pedals when possible during training Physical therapy - stretching, strengthening of toe flexors and tibialis posterior, proprioceptive training