MINI-INVASIVE COMPUTER ASSISTED BI-UNICOMPARTIMENTAL KNEE REPLACEMENT.

Abstract

Nowadays unicompartimental knee replacement (UKR) is a valuable solution for the treatment of knee osteoarthritis. Likewise in selected cases bicompartimental arthritis of the knee in patient younger than sixty still remains a challenge for the orthopaedic surgeon. In this selected cases, the Authors present their experience in performing a mini-invasive bi-unicompartimental knee replacement assisted by a computer navigation system trying to obtain both a correct alignment and a soft tissue balancing.

From January to December 2003, the Authors treated 5 patients (5 knees) with bicompartimental arthritis of the knee. The mean age was 66 and in all the cases there was a arthritis deformity with intact both ACL and PCL without any pain at the femur-patella joint. All the patients had previously undergone to multiple surgical procedures. Orhophilot (4.0 version) navigation system (Aesculap, Tuttlingen, Germany) was used during the surgery to assist prosthesis placement. In all the cases a minimal surgical approach was used (7 to 9 cm skin cut). The patients were assessed using a UKR dedicated outcome score, Italian UKR User’s Group (G.I.U.M.) score, pre-operatively and at the latest follow-up. Pre-operatively the mean GIUM score was 49.1 (range 26–63) At the lastest follow-up the mean GIUM score was 80.2 (range :75–94). The average femoral-tibial angle was 179° (range 177° −181°). All the patients had a good ligament balancing with computer assisted spreader device. All the patients were satisfied and had returned to their previous occupation soon.

According to their previous experience performing bi-unicompartimental prosthesis, the Authors underline how the computer navigation system support ligaments balancing and a correct prostheses alignment. They emphasize this real mini-invasive surgical approach to the cure of the knee arthritis, above all in young patients with post traumatic deformities.