Ligament reconstruction versus distal realignment for patellar dislocation

Abstract

Recently, medial patellofemoral ligament reconstruction has been emphasized for the treatment of patellar dislocation. This study compared the results of medial patellofemoral ligament reconstruction by adductor magnus tenodesis with distal patellar realignment in patients with recurrent patellar dislocation. Additionally, the development of patellofemoral osteoarthrosis was compared for these two procedures at a median 10-year followup. Between 1994 and 2000, 47 consecutive patients were treated for recurrent patellar dislocation by adductor magnus tenodesis (18 knees) or Roux-Goldthwait procedure (29 knees). Redislocations, subjective symptoms, and functional outcomes were evaluated. Magnetic resonance imaging was performed at followup. The incidence of patellar redislocation after surgery was 7% in the adductor magnus group and 14% in the Roux-Goldthwait group. Median Kujala scores were 88 for the adductor magnus group and 86 for the Roux-Goldthwait group. Magnetic resonance imaging revealed patellofemoral articular cartilage lesions in 22 knees (73.3%) at followup, including 14 (46.6%) with full-thickness cartilage loss. Radiographs revealed patellofemoral osteoarthritis in five patients in the Roux-Goldthwait group and in none of the patients in the adductor magnus group. Adductor magnus tenodesis is a reliable method to treat recurrent patellar dislocation. The medial patellofemoral ligament reconstruction seems to reduce the risk of osteoarthrosis compared with distal realignment surgery.

Level of evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Fig. 1

The medial patellofemoral ligament (MPFL, arrowhead) attaches firmly to the femur just anterior to the medial epicondyle (arrow). The distal insertion of the adductor magnus tendon (ADD.MG.). (Reprinted with the permission of Lippincott Williams & Wilkins from Avikainen VJ, Nikku RK, Seppanen-Lehmonen TK. Adductor magnus tenodesis for patellar dislocation: technique and preliminary results. Clin Orthop Relat Res. 1993;297:12–16.)

Fig. 2

The distal part of the adductor magnus tendon (ADD.MG.) is cut approximately 8 cm proximal to its distal insertion. The graft is then fixed near the medial border of the patella to reconstruct the medial patellofemoral ligament (MPFL, arrowhead). (Reprinted with the permission of Lippincott Williams & Wilkins from Avikainen VJ, Nikku RK, Seppanen-Lehmonen TK. Adductor magnus tenodesis for patellar dislocation: technique and preliminary results. Clin Orthop Relat Res. 1993;297:12–16.)

Fig. 3A–B

Plain axial radiographs show the patellofemoral joint (A) before surgery and (B) 10 years after surgery with patellofemoral osteoarthritis. The 29-year-old patient had more than one redislocation after surgery.

Fig. 4

An MR image shows a severe patellofemoral articular cartilage defect (small arrow) and osteoarthrosis deformities (large arrows) in a 29-year-old patient 9 years after surgery.