The average IKS Knee score was 72 (23–97) and the functional score was 68 (0–100) with 74% experiencing none or only mild pain. The SF12 assessment revealed a mean physical score of 55 (14–99). Ninety per cent of patients were satisfied with their knee and 89% would have the operation again if required. There was one operative death (PE), one deep infection, 3 PE’s, 3 DVT’s and 5 superficial infections. An MUA was required in 9 cases. Eight knees were revised. Using ‘all revisions’ as an end point. The survival rate was 95.3% at 10 years.
To determine whether increased sagittal laxity has an effect on functional outcome following posterior cruciate retaining total knee replacement using two differing tibial insert designs. Ninety-seven patients were reviewed clinically, radiologically and underwent KT1000 testing of their TKR at a minimum follow up of 5 years (mean 6.5 yrs). The femoral component design was the same in all patients (Duracon/PCA). Fifty two patients had a relatively flat tibial insert design (group 1), while 45 patients had an AP lipped insert (group 2) following a change in design in 1995. The 2 groups were comparable for age, sex, Charnley category, BMI, tibial slope and follow up. There was no significant difference in laxity measurements, IKS or WOMAC scores between the groups. There was no significant correlation between laxity and outcome score or flexion range. Increased sagittal laxity in a knee replacement does not have a strong influence on functional outcome. The differing tibial insert designs had no significant effect on either laxity or function.
Magnetic Resonance Imaging is increasingly utilised for the assessment of knee pathology. The aim of this study was to review our entire knee MRI scans and to assess the accuracy of diagnosis when compared with operative diagnosis. Using data from the radiology department and medical records (public and private) all patients having knee MRI scans in a 6-year period were identified. There were 956 scans performed on 930 patients. Scan diagnosis, operative diagnosis and diagnostic accuracy were assessed. Of the scanned patients 181 (19.5%) had normal scans and of these 168 (92.8%) were accurately diagnosed as normal. The remaining 749 (80.5%) had an abnormality noted on scan and of these 298 (39.8%) proceeded on to surgery. Of those patients having surgery, diagnosis at surgery was found to exactly match the results of the scan in 163 (57.0%) patients. Furthermore 51.5% of patients with a diagnosis of meniscal degeneration by scan actually had a meniscal tear at operation. However the sensitivity for diagnosis of ACL tears was 89.0% and that of medial meniscal tears was 90.6%. MRI diagnosis is far from infallible and clinicians should be conscious of its limitations. However it is particularly reliable in confirming the lack of pathology within a knee with an accuracy of 93%. It also has high sensitivity for diagnosis of ACL and meniscal tears.
There are numerous papers from specialist arthroplasty centres outlining results of total knee replacement. This review was performed as there is little information on results in general orthopaedic centres. All patients received a Duracon/PCA replacement between 1992 and 1996. Patients were assessed clinically, fluoroscopically and completed SF12, WOMAC and IKSS questionnaires. At a mean of 6.7 (5–9) years follow up 93 (78%) were available for review. The average age was 70 years (52–88) with 58% being male. The primary diagnosis was osteoarthritis in 94.3%, with 41 %, 38% and 21 % being Charnley grades A, B and C respectively. The average IKS knee score was 71.4 (23–96) and functional score 70 (0–100), with 72.7% experiencing none or only mild pain. The SF12 assessment revealed a mean physical score of 38 (14–63) and mental score of 53 (25–67). There were 88.6% of patients satisfied with their knee and 92% would have the operation again if required. There were no deep infections or PE’s but there were 7 superficial infections and 2 DVT’s. A MUA was required in 8 patients. One patient retains a radiologically loose prosthesis at 8 years but had mild pain with stairs only, a WOMAC functional score of 85 and was happy. There was a best-case survival of 94.4% at 5 years. There were 5 knees revised in 5 patients and no revisions of the deceased patients, all surviving greater than 5 years from surgery. These results suggest that those in general orthopaedic centres are a little less reliable than those in specialist centres. However they are acceptable and patient satisfaction remains high.
