The Management of Extensor Mechanism Complications in Total Knee Arthroplasty

Abstract

Complications involving the knee extensor mechanism and patellofemoral joint occur in 1% to 12% of patients following total knee arthroplasty and have major negative effects on patient outcomes and satisfaction. The surgeon must be aware of intraoperative, postoperative, and patient-related factors that can increase the rate of these problems. This review focuses on six of the most commonly encountered problems: patellar tendon disruption, quadriceps tendon rupture, patellar crepitus and soft-tissue impingement, periprosthetic patellar fracture, patellofemoral instability, and osteonecrosis of the patella. The goals of this report are to (1) review the relevant anatomy of the knee extensor mechanism, (2) present risk factors that may lead to extensor mechanism complications, (3) provide a diagnostic and treatment algorithm for each of the aforementioned problems, and (4) review the specific surgical techniques of Achilles tendon allograft reconstruction and synthetic mesh augmentation. Extensor mechanism disorders following total knee arthroplasty remain difficult to manage effectively. Although various surgical techniques have been used, the results in patients with a prior total knee arthroplasty are inferior to the results in the young adult without such a prior procedure. Surgical attempts at restoration of the knee extensor mechanism are usually warranted; however, the outcomes of treatment of these complications are often poor, and management of patient expectations is important.

Primer total diz artroplastisinde karşılaşılan patello-femoral sorunlar ve çözümleri

“…Spesifik etiyolojik faktör belirlenerek, ona yönelik cerrahi tedavi uygulanması en başarılı sonuçları vermektedir. [26] Eğer herhangi bir komponent pozisyon sorunu ya da ekstremite dizilim sorunu ortaya konamıyorsa, lateral retinakuler gevşetme (gerekirse proksimal ve distal dizilim düzeltici girişimlerle de desteklenerek) uygulanabilir. Ancak, daha önceki bölümlerde de belirtildiği üzere, bu tür olgularda nüks ve re-operasyon riski yüksek görünmektedir.…”

Etiopathogenic bases for patellofemoral arthritis development

“…В част-ности, Singerman и соавт. докладывают, что при patella аlta нагрузка на суставные поверхности возрастает при сгибании в пре-делах 0-60°, достигая пика при 90° [57]. Luyckx, используя данные динамическо-го симулятора КС, демонстрировал мини-мальную нагрузку на фасетки при 35-70°, максимальную -при 70-120°, причём по сравнению с нагрузкой при нормальном надколеннике эта нагрузка многократно воз-растала, потому что в норме рычаг силы четырёхглавой мышцы превалирует над ры-чагом силы связки надколенника [58].…”

ACR Appropriateness Criteria ® Imaging After Total Knee Arthroplasty

“…Bone Scan. Radionuclide three-phase bone scans can demonstrate increased activity at a site of periprosthetic fracture and can show fractures that are radiographically occult [143,144]. In older osteopenic individuals with low rates of bone remodeling, it may take 48 to 72 hours for development of increased radionuclide activity at the site of fracture.…”