Working Diagnosis:
Peripheral artery disease leading to thrombosis in the distal superficial femoral artery and left popliteal artery causing a functional popliteal artery syndrome.

Treatment:
The patient was offered by bypass surgery versus non-invasive interventions such as medical management and a graded exercise program. After shared decision making, the patient was started on cilostazol (a PDE3 inhibitor) and was prescribed a graded exercise regimen.

Outcome:
The patient initiated the above interventions with an improvement in his symptoms. He was subsequently lost to follow-up. However,several months later he contacted his primary care physician and was noted to be more active, including swimming recreationally without difficulty/limitation.

Author's Comments:
Calf pain, particularly after athletic activity, is a common chief complaint. Often the etiology is musculoskeletal in nature; however, it is important to consider alternative etiologies, especially when there is a failure of improvement with standard conservative treatment. In this case, we discuss a patient with calf pain who failed to improve after physical therapy. He was ultimately found to have an occlusion of his popliteal artery, which was consistent with the patient's symptoms. While there have been other cases reported of popliteal artery occlusion as a result of popliteal artery entrapment, this case is unique given the patients lack of risk factors for peripheral artery disease and the absence of anatomic popliteal artery entrapment on imaging.

There are six types of popliteal artery entrapment with types I-V consisting of entrapment by either surrounding muscles or fibrous bands and Type VI being described as a functional entrapment. For types I-V, surgical release of the muscle or tendon causing the entrapment is the ultimate treatment. For functional popliteal artery entrapment syndrome, botulinum toxin has been described as a method of non-operative treatment. Additional treatment options in this particular patient with a vascular occlusion are similar to a patient with peripheral artery disease which includes medication management with a graded exercise program, thrombolysis, stent placement or vascular bypass of the affected region.

Editor's Comments:
Popliteal artery entrapment may be congenital or acquired. Diagnosis can often be delayed. It may be misdiagnosed as Chronic Exertional Compartment Syndrome, resulting in inappropriate surgical interventions. Distal pulses are often normal on exam, unless there is full artery occlusion. Ankle- Brachial Index can be performed post-exercise to assist in diagnosis. If popliteal artery occlusion goes undiagnosed, it can lead to limb ischemia or aneurysm formation.

References:
1. Lohrer H, Malliaropoulos N, Korakakis V, Padhiar N. Exercise-induced leg pain in athletes: diagnostic, assessment, and management strategies. Phys Sportsmed. 2018:1-13.
2. Green B, Pizzari T. Calf muscle strain injuries in sport: a systematic review of risk factors for injury. Br J Sports Med. 2017;51(16):1189-1194.
3. Wright LB, Matchett WJ, Cruz CP, et al. Popliteal artery disease: diagnosis and treatment. Radiographics. 2004;24(2):467-479.
4. Regus S, Lang W. Popliteal Artery Occlusion Caused by Entrapment Syndrome in a Female Long Distance Runner. Eur J Vasc Endovasc Surg. 2016;51(2):293.
5. Dyer KT, Hogrefe CP. Don't Just Blame it on the Veins: An Update on Vascular Exertional Limb Pain. Curr Sports Med Rep. 2018;17(10):347-353.

Return To The Case Studies List.