2002 OITE Question 42

Question

A 13 y/o boy has peripatellar knee pain with tenderness reproduced by palpation at the proximal lateral corner of the patella. He denies any history of trauma. Activity restrictions, quad strengthening, and NSAIDS have failed to provide relief. A radiograph is shown in figure 7. Treatment should now consist of

1. lateral retinacular release.

2. distal patellar tendon realignment.

3. chondroplasty.

4. advancement of the vastus medialis.

5. patellectomy.

Figures

Answer (click for answer)

Preferred answer: 1

Discussion: A painful bipartite patella is most commonly seen in adolescent males and females who participate in strenuous athletic activities. The bipartite patella most commonly is characterized by chrondroosseous disruption of the superolateral pole of the incompletely ossified patella during the growth stage. Pain is caused by persistent traction forces. The vastus lateralis muscle and the lateral retinaculum exert considerable force on the patellar fragment. Surgical release of these forces can alleviate pain. As always, non-operative treatment with stretching, NSAIDS, activity modification, and bracing is the first course of action. This patient has a superolateral bipartite patella and has failed conservative treatment. Answer #5 is WAY OVERKILL !! The question does not give any history of patellar malalignment and therefore #2 is wrong. The radiograph and question do not address chondromalacia of the patella and therefore performing a chondroplasty(#3) is not a good answer. Answer #4 would not do anything to relieve the traction forces on the patellar fragment. Answer #1 is an accepted treatment for this condition. This option avoids excision of the fragment and the necessary immobilization of the knee.

Reference: Mori Y, Okumo H, Kuroki Y: Efficacy of lateral retinacular release for painful bipartite patella. Am J Sports Med 1995;23:13-18.


Ogata K: Painful bipartite patella: A new approach to operative treatment. J Bone Joint Surg Am 1994;76:573-578.