25 year old female with chronic knee pain had radiographs obtained of the knee joints. There is chronic anterior and superior dislocation of the tibia with respect to femur, left worse than right knee joint. There is genu recurvatum.

She has Larsen syndrome which is associated with unusually large range of joint movement (hypermobility). Larsen syndrome is a rare genetic disorder. Surgical repair has high failure rates due to abnormal connective tissue.