Figure. Lateral radiograph of the left knee.
A 36-year-old woman presents with pain in her left knee that has persisted for 8 weeks. She reports injuring her knee in a fall sustained on vacation. The patient returned home 2 weeks after sustaining the injury and was diagnosed with a knee sprain at a local urgent care center. She was placed in a knee immobilizer and has been walking on the leg with only mild pain. She seeks further treatment as she has not been able to walk without the immobilizer and cannot bear weight on the left leg. Physical examination finds that the patient is unable to complete a straight leg raise on the left side. Lateral radiograph of the left knee (Figure) shows severe patella alta.
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The patient has severe patella alta, a high-riding patella that indicates a patella tendon rupture has occurred. Patella baja, or a low-riding patella, is indicative of a quadriceps tendon rupture. Repair of a patella tendon rupture must be performed in a timely manner as the patella starts to retract proximally in as little as 2 weeks.1
Acute tears can be treated with a tendon-to-tendon repair or by suturing the tear to the inferior pole of the patella.1 Neglected or chronic ruptures present after 6 weeks from injury due to neglect or a missed diagnosis. As time from injury passes, the patella and surrounding tissue retract proximally, which makes reducing the patella tendon back down to the tibia increasingly difficult.1,2
During open surgical repair, if the gap between the tissue ends is less than 2 cm, a distal release of the quadriceps tendon or proximal transposition of the tibial tubercle can be used. If the gap is larger than 2 cm, a graft must be used to bridge the tissue ends. Ipsilateral hamstring gracilis and semitendinosus tendon grafts (the same tendons often used for an anterior cruciate ligament autograft) are types of frequently used grafts.1,2
Studies have shown that a patella tendon reconstruction with soft tissue autograft provides a good functional recovery and a return to pre-injury level of function.1,2
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor in chief of the Journal of Orthopedics for Physician Assistants.
1. Maffulli N, Del Buono A, Loppini M, Denaro V. Ipsilateral hamstring tendon graft reconstruction for chronic patellar tendon ruptures: average 5.8-year follow-up. J Bone Joint Surg Am. 2013;95(17):e1231-1236.
2. Sundararajan SR, Srikanth KP, Rajasekaran S. Neglected patellar tendon ruptures: a simple modified reconstruction using hamstrings tendon graft. Int Orthop. 2013;37(11):2159-2164.