Background: CT scanning is an essential part of the preoperative planning process prior to surgical fixation of acetabular fractures. Considerable disparity exists between the clinical and radiological outcome following open reduction and internal fixation of these fractures. It is suggested that this disparity is due to poor assessment of the quality of reduction using plain radiographs alone.

Aim: To investigate the role of post-operative CT scanning following ORIF of acetabular fractures.

Methods. Prospective study commenced in January 2000 of all patients in our institution undergoing internal fixation of acetabular fractures. Post operative axial CT scans were compared with plain radiographs (AP pelvis and 45 degree oblique Judet views) with regard to the sensitivity to detect articular fracture reduction in terms of gap displacement and step deformity or offset. A simplified binary measurement of radiological outcome was used stratifying radiological result into anatomical and non anatomical. Three observers independently reviewed the plain radiographs and CT scans at two separate time points and categorised the radiographic outcome as described. The interobserver reproducibility and intraobserver reliability of these measurements was expressed as a kappa statistic. In addition in those patients greater than 18 months following surgery we attempted to correlate the radiographic with the clinical outcome using the Harris hip score and the SF-36 score.

Results: 20 patients were recruited. Plain films were equieffective in detecting post-operative articular fragment displacement (p=0.24). The interobserver and intraobserver agreement between the radiological outcome measurements were good with respective kappa values of 0.61 and 0.65. There was a weak association between clinical and radiographic outcome as ascribed by post operative CT scans.

Conclusion: While there may be an argument for the use of post operative CT scanning of acetabular fractures in selective cases, we did not find any significant benefit of CT scans over plain radiographs in the assessment of reduction or radiological outcome following these injuries. Hence we do not routinely advocate their use in the post operative setting.

Introduction: The majority of patients with osteoarthritis of the knee suffer from femorotibial pain with a smaller proportion suffering predominantly patellofemoral symptoms. No clear consensus exists as to the need for patellar resurfacing when performing total knee replacement for patients with symptomatic femorotibial osteoarthritis but without prominent patellofemoral symptomatic and radiographic disease.

Aims: To identify the advantages and disadvantages of both resurfacing and non-resurfacing of the patella during cemented total knee replacement performed for osteoarthritis predominantly of the femorotibial joint. To objectively clarify the rationale for the use of either procedure in clinical practice.

Methods: Prospective randomised double blinded clinical trial. Patients with osteoarthritis of the knee and principally femorotibial symptoms were included. Patients with rheumatoid arthritis, gross deformity of the knee and gross radiological or clinical patellofemoral arthritis were excluded. The implant used was a cemented posterior stabilised AMK (DePuy, Leeds UK) prosthesis. Preoperative American Knee Society Score, SF-36 questionnaire and WOMAC scores were calculated for each patient. These instruments were repeated and combined with clinical and radiological follow up at 3 months, 6 months and 1 year.

Results: 58 patients were recruited into the study, 53 of whom completed follow up and were in included in the analysis. Baseline characteristics were similar in each group. Operating room time was less in the non-resurfaced group (p< 0.05). At 2 years, 3 patients in the non resurfaced group had undergone a revision procedure. There was no difference between the resurfaced and non-resurfaced groups in terms of global functional outcome as measured by SF36 and WOMAC scores at 1 and 2 years post-operatively. The American Knee Society score showed no difference between the two groups (p=0.86) at 1 year post surgery.

Conclusion: There is no significant difference in clinical outcome at 1 and 2 years following surgery vis-à-vis those who did and did not have patellar resurfacing performed during knee replacement for predominantly femorotibial symptomatic osteoarthritis. There was a higher revision rate in the non-resurfaced group. In TKR using a PS AMK prosthesis routine resurfacing of the patella should be performed.