Chronic Knee Dislocation After Total Knee Arthroplasty

Abstract

Knee dislocation after total knee arthroplasty (TKA), although rare, is a dangerous injury that can lead to neurovascular compromise and permanent disability. Chronic dislocation after TKA is even less common and is defined as dislocation that is present for 4 weeks or more. There are few reports of its management. Chronic dislocation may be complicated further by concomitant extensor mechanism disruption, ligamentous instability, and/or capsular contracture. This article describes 3 cases of chronically dislocated TKAs and the challenges encountered in treating this difficult problem. A higher level of constraint was required to maintain knee stability, and an extensor mechanism allograft was needed in 2 of the 3 reported patients. The preferred technique at the authors' institution is a complete allograft composite, tensioned in full extension. In the setting of a chronically dislocated TKA, the authors now recommend revision surgery with an enhanced measure of constraint (constrained condylar device or hinged knee prosthesis), reconstruction of the extensor mechanism when necessary, and restoration of the joint while compensating for concomitant bony defects. Even when surgeons follow these principles, it is important to inform the patient that long-term outcomes will likely be inferior to those of revision surgery for other causes.

Neglected Posterior Dislocation Septic Loosening and Prolonged Flexion Contracture of Total Knee Arthroplasty: A Case Report

“…Chronic dislocation of primary TKA, defined as being older than 4 weeks [ 13 ], is even more uncommon, and can be further complicated by marked instability, fixed angular deformity, extensor mechanism disruption, severe bone loss, and infection, as in our case. Ross et al [ 13 ] reported 3 cases of chronic posterior primary TKA dislocations; 2 of them had BMI >40, all requiring a higher level of constraint to maintain knee stability, and an extensor mechanism allograft was needed in 2 of them.…”

“…Chronic dislocation of primary TKA, defined as being older than 4 weeks [ 13 ], is even more uncommon, and can be further complicated by marked instability, fixed angular deformity, extensor mechanism disruption, severe bone loss, and infection, as in our case. Ross et al [ 13 ] reported 3 cases of chronic posterior primary TKA dislocations; 2 of them had BMI >40, all requiring a higher level of constraint to maintain knee stability, and an extensor mechanism allograft was needed in 2 of them. Chu et al [ 12 ] reported a posterior TKA dislocation in a 54-year-old woman with septic TKA, which was treated initially with debridement and antibiotic beds; she had the dislocation 11 days after surgery as a result of posterior cruciate ligament tearing due to infection.…”

Tibiofemoral dislocation after total knee arthroplasty treated successfully with an external fixation device

“…Furthermore, several case reports have identified obesity as the direct cause of post-TKA dislocation [ 10 ]. It correlates with poorer muscle quality and a greater risk of medial collateral ligament avulsion [ 3 , 5 ]. The mean BMI of patients with tibiofemoral dislocation after TKA has been reported at 33 kg/m 2 [ 4 ].…”

Medial Patellofemoral Ligament Reconstruction Using the Hamstring Tendon for Patellofemoral Joint Instability in an 81-Year-Old Female

“…However, among aged populations, cases of total knee arthroplasty (TKA) for knee OA with permanent patellar dislocation [11] or lateral patellar dislocation after TKA are often reported [12, 13]. Accordingly, the authors concluded that the causes of lateral dislocation of the patella after TKA are component malpositions of an anterior, internally rotated, and medial femur; internally rotated tibia; and lateral patella.…”