The Use of the McKeever Metallic Hemiarthroplasty

We reviewed the results of sixty-one McKeever unicompartmental arthroplasties performed by the senior one of us (T. P.) for osteoarthritis of the knee. The average follow-up was five years (range, two to thirteen years). Forty-four (72 per cent) of the arthroplasties were rated as good to excellent. The average postoperative range of motion in these knees was 110 degrees. Six knees were rated as fair and eleven knees, as poor. The poor results appeared to be caused by degenerative arthritis involving ipsilateral compartments that had not been resurfaced with an implant. Osteoarthritis of the knee joint is not infrequently confined to one compartment, usually the medial one, with the lateral compartment being relatively free of disease7’3. The best treatment for this problem is controversial, and various methods have been proposed. including both tibial and femoral ‘ 3.7.8. 0. 15 , unicompartmental cemented prosthetic replacement4’2, and total joint replacement9 ‘ . With time, it has become clear that the cemented total joint prosthesis, particularly in the young or active patient, has an appreciable risk of failure, primarily because of loosening at the bone-cement interface59. Salvage of a failed cemented implant is a major surgical challenge”. The reported results of tibial osteotomy for medial compartment * Read at the Annual Meeting of The American Academy of Orthopaedic Surgeons, New Orleans, Louisiana, January 25, 1982. t Cambridge Hospital. 1439 Cambridge Street. Cambridge, Massachusetts 02139. New England Baptist Hospital. 91 Parker Hill Avenue. Boston, Massachusetts 02120. osteoarthritis with yams deformity have appeared to be generally satisfactory to date’ 376’. The reported results of tibial osteotomy for lateral compartment disease and valgus deformity have not been as satisfactory, however, and Shoji and Insall have stated that high tibial osteotomy is contraindicated in this situation. The alternatives that they have suggested are a supracondylar femoral osteotomy in the younger patient and a total knee replacement in the older patient. However, it has been reported that motion of the knee is frequently restricted following femoral osteotomy for arthritis6. Articular replacement of both joint compartments for unicompartmental arthritis seems excessive, and the results with cemented unicompartmental total joint replacements have been inconsistent459 2 A series of exclusively unicompartmental uncemented tibial-plateau arthroplasties for osteoarthritis has not been previously reported. Prior reports have combined unicornpartmental and bicompartmental implants in both rheumatoid and osteoarthritic patients”’4. The senior one of us (T. P.), however, has used the McKeever prosthesis as a hemiarthroplasty in knees with unicompartmental osteoarthritis since 1971 (Figs. 1 , 2, and 3). The purpose of this paper was to retrospectively study this experience in an attempt to determine the role of the McKeever prosthesis in the treatment of unicompartmental osteoarthritis.