Hand-made articulating spacers in two-stage revision for infected total knee arthroplasty: Good outcome in 30 patients

Background and purpose The most reliable results when treating an infected total knee arthroplasty have been obtained with a two-stage reimplantation protocol. We have used a simple technique for hand-made spacers and now report the outcome.

Patients and methods 30 patients with an infected total knee arthroplasty (TKA) were treated with a 2- stage reimplantation protocol. Spacers were built and customized to the type of defect using only 2 retractors and a high-speed tip burr. Partial weight bearing and discharge from the hospital were encouraged in the time between surgeries. 29 of 30 patients (97%) had successful reimplantations and they were followed for an average of 3 (2–5) years.

Results Range of motion with the articulating spacer averaged 80° (55–100) and 21 of the 30 patients achieved motion greater than 75°. At the latest follow-up, there were no reinfections. According to the Knee Society score (KSS), the results were considered excellent or good in 25 patients, and fair or poor in 4 of the 29 patients with reimplantations. Motion after reimplantation averaged 107° (90–120).

Interpretation One of the key factors related to a successful outcome with a two-stage reimplantation procedure is to keep the joint mobile and functional in the time between surgeries. Hand-made articulating spacers retain most of the advantages of more complex spacers in terms of mobility, pain, bone loss, success, or re-infection rate—with the major advantages of price and universal availability. Limitations related to this technique include potential knee instability, the need to walk with an orthosis, and the risk of subluxations.