Quality of life after knee arthroplasty. A randomized study of 3 designs in 42 patients, compared after 4 years

We assessed different yardsticks for outcome 4 (3-5) years after surgery in a prospective, randomized study of 42 patients, where 3 designs of cemmentless knee prostheses were used. The prognosis with regard to loosening, previously obtained by radiostereometry after 2 years of follow-up, was utilized. Patients with a prognosis of stable implant fixation (two thirds) were compared with those where loosening was predicted (one third). Hospital for Special Surgery score and Visual Analogue Scales regarding pain at rest, "first step" pain, pain during activity and global function, showed consistent postoperative improvements, but no differences between the design and prognosis groups were found. Radiolucent lines were registered both as yes/no and number of zones. Lines and prognosis were associated, but not lines and design groups. Quality of life assessment by the Nottingham Health Profile questionnaire showed that the poor prognosis group had increased pain and significant disturbances of sleep and emotions, as well as difficulty in enjoying hobbies and holiday activities. No differences were found between the design groups. Altogether, the patients showed profiles comparable to a healthy reference group. We conclude that the Nottingham Health Profile is a sensitive, relevant and simple measure of outcome after knee arthroplasty.