Popliteal entrapment as a result of neurovascular compression by the soleus and plantaris muscles.

Intermittent claudication may occur in well-conditioned athletes because of an unusual form of popliteal artery entrapment that results from overtraining. These patients complain of calf muscle cramping, rapid limb fatigue, and occasional paresthesias on the plantar surface of the foot when running on inclines or when repetitive jumping is performed. Results of plethysmographic screening tests for popliteal entrapment are positive in these patients. Magnetic resonance angiography and intravenous digital subtraction angiography studies, however, do not demonstrate findings typical of anatomic popliteal entrapment. No evidence exists of aberrant positioning of the popliteal artery in foot neutral positioning, but with forced plantar flexion, the neurovascular bundle is deviated and compressed laterally. Surgical exploration of the popliteal fossa demonstrates no obvious musculotendinous abnormality. Symptoms of claudication and arterial compression are relieved by surgical release of the soleus muscle from its tibial attachments, resection of its fascial band, and resection of the plantaris muscle.