Botulinum toxin as a treatment for functional popliteal artery entrapment syndrome.

Purpose: Functional popliteal artery entrapment syndrome is responsible for exercise-induced muscle leg pain. This syndrome is caused, in most of the cases, by the excessive size of the gastrocnemius muscles. Currently, its treatment is based only on surgery with variable results.

Methods: We report the case of a young professional soldier in a combat unit with bilateral functional popliteal artery entrapment syndrome that was confirmed by dynamic arteriography, magnetic resonance angiography, and ultrasonography and did not improve after bilateral popliteal arteriolysis without resection of the gastrocnemius medial head. Treatment by injecting botulinum toxin in the proximal part of the gastrocnemius muscles was proposed and carried out.

Results: Regular follow-up (from 1 month to 3 yr after botulinum toxin treatment) showed the disappearance of exercise-induced pain and the improvement of the patient's physical and sports performance. Results of follow-up ultrasonography during dynamic maneuvers at 2.5 months and 2 yr after botulinum toxin injection were normal. Neither adverse effects nor motor deficit of the gastrocnemius muscles was reported.

Conclusions: This case report suggests that botulinum toxin treatment could be an alternative to surgery for patients with functional popliteal artery entrapment syndrome. Botulinum toxin could reduce functional compression and, consequently, exercise-induced pain by decreasing the volume of the gastrocnemius muscle.