The long-term results of the Liverpool Mark II knee prosthesis.

We have reviewed 105 Liverpool Mark II knee replacements in 71 patients to assess survival and long-term results. Assessment was both clinical and radiological, using a modification of the British Orthopaedic Association knee function assessment chart, and analysis was by the survivorship method as advocated by Tew and Waugh. The follow-up period was between 13 and 113 months with 42 prostheses being in situ for over six years. Eight knees (7.6%) have been revised or arthrodesed because of infection or loosening, giving a cumulative success rate of 89% after seven years based on prosthesis survival alone. Of the remaining knees, 71.1% were either free of pain or caused only minimal pain. The cumulative success rate as judged by the stricter criteria of the prosthesis being in situ and causing little or no pain suggested a 50% survival between 73 and 96 months. Most patients (77.3%) were enthusiastic or satisfied with their results. Complications included deep wound infection (8.6%), and loosening which needed further surgery (11.4%).

A review of the Liverpool elbow prosthesis from 1974 to 1982.

Eighty elbows in 65 patients with an average age of 57 years have had two-part non-constrained Liverpool elbow arthroplasties performed since 1974. Fifty-five had rheumatoid arthritis, eight osteoarthritis or ankylosis secondary to injury, one osteochondritis dissecans and one pyknodysostosis. The average preoperative range of movement was 42 degrees to 112 degrees with 47 degrees of pronation and 42 degrees of supination. There was significant gain in the arc of movements at follow-up: 32 degrees in the extension-flexion range (average range 32 degrees to 134 degrees of flexion) and 42 degrees in forearm rotation (average pronation 69 degrees and supination 62 degrees). Before operation severe pain was the predominating symptom in 43 elbows (53.8%) but after replacement there was only moderate pain in five elbows (6.2%). The results were excellent in 42 (52.5%), good in 15 (18.7%), fair in 9 (11.3%) and unsatisfactory or poor in 14 (17.5%). Eight elbows required revision of the arthroplasty: three were post-traumatic, disorganised or osteoarthritic joints, three rheumatoid and both elbows in the patient with pyknodysostosis. Loosening of the prosthesis (particularly the humeral component) was the common factor necessitating revision. Of six rheumatoid elbows needing removal of the implant, four had deep infection, one had a dislodged humeral component as a result of injury and in one a divided olecranon had developed non-union. Rheumatoid elbows benefited more than post-traumatic arthritic elbows from the operation. (ABSTRACT TRUNCATED AT 250 WORDS)

The Liverpool Mark II knee prosthesis. A preliminary report.

This is a preliminary report of the results of knee joint replacements using the Liverpool Mark II knee joint system which consists of a bicondylar prosthesis and a set of stereotactic instruments. The prosthesis has been developed from Gunston's concept, and the special instruments ensure its accurate insertion through meniscectomy-type incisions placed on either side of the patella. Particular features of the prosthesis are near-normal articulation, and the simplicity of the operation. Sixty-two knee replacements were implanted in forty-two patients between the spring of 1974 and January 1977. After the operation fifty-six knees were painless and four others produced only slight pain. Full extension was obtained in fifty-eight knees, and none showed a valgus or varus deformity. Collateral laxity was absent in all knees. There were two failures. These early results are most encouraging.