Abstract
The Dual Articular Knee (Biomet®) is a modular revision prosthesis with a mobile bearing. We performed 24 operations on 23 patients: 16 female and 7 male patients. The average age at revision was 71.6 years, range 42–84 y, the average time span between primary TKR and revision was 8 years, range 1–19 y. The average follow up was 25 months, range 3–68 months.
Diagnoses at primary TKR were: Osteoarthritis 19, Rheumatoid arthritis 1, Post-traumatic arthrosis 2, s/a medial Unicondylar 1, s/a High Tibial Osteotomy 1.
Primary Implants were: Total Condylar (Howmedica) 4 (3 with metal trays and 1 all PE tibia); IB 2 (Zimmer) 9, IB 1 (Zimmer) 2, Miller Galante (Zimmer) 1, AGC (Biomet) 5, Sigma (J& J) 2, Sigma RP (J& J) 1.
Inciations for revision were:
Aseptic loosening and PE wear 20, Infection 4 (Organisms: MRSA 1, Enterococcus Faeconium 1, Streptococcus Gr.6 1, Negative Culture 1).
Surgical Technique: We used a medial parapatellar approach in 22 knees and the lateral parapatellar approach in 2 knees, osteotomy of the tibial tuberosity was performed in 16 operations and a lateral patellar release in 7. The patellar implant was replaced in 5 knees, left in situ in 4 and not replaced in 15 knees (one of the knees was after a previous patellectomy). Two stage revision was performed in 4 infected knees and in one non-infected. Cement spacers impregnated with antibiotics were used in 3 operations. Original implants as temporary implants with antibiotic loaded cement were used in 2 operations.
Results: Results were rated as good if the knee was stable with flexion of 90 degrees or more without evidence of infection and fair with less than 90 degrees of flexion.
Good results were obtained in 19 knees, fair in 2, failure due to late infection in one knee. One patient was lost for follow up, one patient died 6 months after surgery of an unrelated cause.
Conclusions: The Dual Articular Revision Prosthesis is a useful implant system in cases with satisfactory collateral ligament stability.
Correspondence should be addressed to: Orah Naor, IOA Secretary and Co-ordinator (email: ioanaor@netvision.net.il)
