Symptomatic snapping knee from biceps femoris tendon subluxation: an unusual case of lateral pain in a marathon runner

Abstract

Snapping biceps femoris syndrome is an uncommon cause of lateral knee pain and may be difficult to diagnose, resulting in unsuccessful surgical intervention. In this report, we present an unusual case of a 37-year-old male marathon runner with unilateral snapping knee secondary to dislocation of the long head of the biceps femoris over the fibular head during knee flexion. The pain was great enough to interfere with his ability to practice sport. Possible causes of symptomatic snapping knee include multiple intra-articular or extra-articular pathology. Biceps femoris snapping over the fibular head is a rare condition. Reported causes include an anomalous insertion of the tendon into the tibia, trauma, and fibular-head abnormality. However, none of those conditions accounted for his symptoms. Failing conservative treatment, the patient underwent surgery for partial resection of the fibular head, with subsequent sudden resolution of symptoms and return to sport. Accurate knowledge and management of this rare condition is mandatory to avoid inappropriate therapy and unnecessary surgical procedures.

Snapping knee due to the biceps femoris tendon treated with repositioning of the anomalous tibial insertion

“…One component was inserted on the anterolateral aspect of the proximal tibia, and the others were located on the lateral edge and posterolateral portion of the fibular head. In previous cases, snapping knee associated with the biceps femoris tendon has been found to be due to anomalous insertion of the long head of the biceps femoris tendon [ 2 , 3 , 6 , 8 – 10 ], fibular head deformity [ 1 , 5 ], tendon injury [ 4 ], and normal anatomy without trauma [ 13 ].…”

“…Bernhardson and LaPrade [ 4 ] reported three cases of direct arm injury with normal anatomy, in which repair of the injured direct arm resolved the symptoms. Vavalle and Capozzi [ 13 ] described a case with normal location of the long head on the fibular head that presented with a snapping phenomenon. Partial resection of the fibular head resolved the symptoms.…”

Snapping of bilateral biceps femoris tendons: A case report and brief review

“…Etiologies are diverse and grouped under anomalous tendon insertion [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] , subluxation of an anatomically normal tendon [ 12 , 13 ], abnormal fibular morphology [14] , [15] , [16] , [17] or trauma [ 2 , 18 ] with the anomalous insertion etiology being the most common. Symptoms may be mild but, in few cases, they have been reported to affect daily activities [1] .…”

Snapping Biceps Femoris Tendon

“…This condition has been described in various case reports. [2][3][4][5][6][7][8][9][10][11][12][13] The reasons for a snapping biceps femoris can vary, and the treating provider must be ready to accommodate and treat these causes. The symptoms typically include an audible, and usually visual, lateral snapping distal to the knee joint and over the fibular head.…”