Revision Surgery for a Dislocated Constrained Total Knee Arthroplasty

Abstract

Knee dislocation after revision total knee arthroplasty (TKA) is a dangerous, albeit rare, injury that can lead to neurovascular compromise and permanent disability. A paucity of peer-reviewed literature exists regarding this complication after revision TKA. Tibiofemoral dislocation commonly occurs with minimal trauma, such as rising from a seated position, and is commonly associated with a flexionextension gap mismatch. Prompt diagnosis and expedited treatment of this complication is necessary to minimize the risk of adjacent neurovascular structures. Acute management involves attempted reduction, knee stabilization, and thorough neurovascular workup. Long-term management may require revision surgery, with the level of articular constraint necessary being determined intraoperatively. This article describes 2 cases of relatively atraumatic knee dislocations after revision TKA involving the same semiconstrained components. Patient 1 was a 68-year-old man who sustained an atraumatic posterior knee dislocation 2 months after revision TKA. Patient 2 was a 55-year-old woman who presented after an atraumatic posterior knee dislocation 6 months after revision TKA. In both patients, a semiconstrained construct was used with corresponding revision components prior to dislocation. This article includes a synopsis of solutions for flexion-extension gap balancing and a review of the literature regarding this uncommon complication.

Chronic Knee Dislocation After Total Knee Arthroplasty

“…Acute knee dislocation requires an urgent attempt at closed reduction, with careful evaluation of neurovascular status. 1 If unsuccessful, the patient likely requires open reduction with subsequent immobilization for 3 to 10 weeks. 3 If the patient continues to have symptoms of instability, revision surgery is likely necessary.…”

“…Despite excellent long-term results, a small percentage of patients require revision surgery for a variety of reasons. 1 In the setting of aseptic failure, patients may present with component loosening, polyethylene wear, patellofemoral maltracking, and/or ligamentous instability. 2 Patients with instability have variable presentations, depending on the integrity of the surrounding ligamentous structures and component positioning.…”

“…Modern surgical techniques and attention to component placement have reduced the incidence of gross instability and dislocation after TKA to less than 0.5%. 1 Although dislocation is rare, its consequences can be disastrous. The most feared complication is neurovascular damage, most commonly involving the popliteal artery, common peroneal nerve, or tibial nerve.…”

“…3 Although instability is a common cause of failure after TKA, knee dislocation is rarely seen and less often reported. 1,[4][5][6] Further, chronic dislocation, defined as dislocation present for 4 weeks or more, is even less common. To the authors' knowledge, this article is the first report of this event.…”

Çift Taraflı Diz Protezi Sonrası Ortaya Çıkan Komplikasyonlar

“…Mihaiko ve ark (11) diz protezi cerrahisinde fleksiyon ve ekstansiyon bojiuklannin e §it olarak dengelenmesinin önemini vurgulamaktadir Schuh ve ark (12), çalijmalannda hareketii sistem insört kulianilan dizlerde olujan çikiklar sonrasi insört degijimi yerine revizyon diz protezi ameliyati yapilmasmi önermektedirier. Hagedom ve ark (13) yaptikiari çalijmada revizyon diz protezi yapilan hastalarda diz çikigmm en önemli nedeni olarak fleksiyon ve ekstansiyon araliklarmm ejit olmamasmi belirtmektedirler Villanueva ve ark (14) yaptiklari çaiijmada alti diz protezi sonrasi eklem çikigi olan hastayi degerlendirmijler dort hastada fleksiyon ekstansiyon dengesizligi, bir hastada komponentlerin malrotasyonunu ve bir hastada da uygunsuz implant seçiminin neden oldugunu belirtmektedirler Ekstansiyon ve fleksiyon açikliklarmm ejit olmamasi ve komponentlerin tespit açilarmm uygun olmamasmm diger dizdeki çikigin nedeni olarak düfünüldü. Biz de insört çikigi olan sol dize arka çapraz bagi kesen sabit insörtlü revizyon diz protezi ameliyati yaptik.…”