This is a study of the quality of outcome of the first 100 patients who received the Twin Peg Oxford Partial knee replacement; which has been designed with a 15 degree extra surface for contact in deep flexion, and two pins for more secure fixation. We measured the outcome in patients with anteromedial osteoarthritis at 2 years after implantation using patient perception outcome measures: the OKS (Oxford Knee Score) and a patient satisfaction questionnaire. We also measured range of motion, the AKS (American Knee Society Score-Objective), the AFS (American Knee Society Score-Functional), and carried out a radiological assessment.

The results showed a mean OKS of 41, a mean AKS of 93, a mean AFS of 84, a mean range of motion of 130 degrees and a 97% satisfaction rate. Results were significantly better in male patients. There were no deaths, infections, dislocations, fractures or revisions. There were no radiolucent lines of 2 mms or more at the femoral bone-cement interfaces.

The introduction of this new version of the Oxford knee shows excellent clinical and radiological results which are at least as good as those seen with the Phase 3 Oxford Partial knee replacement. Small adjustments were made to the minimally invasive approach: a reduced invasive incision for ease of implantation. For those surgeons who are concerned over the risks of femoral loosening with the Phase 3 implant, or desire an improved surface area of contact at high angles of flexion, this Twin Peg Oxford Partial knee replacement offers an excellent alternative.

Objective: To identify risk factors associated with patients that required revision surgery for sciatica.

Design: A retrospective study of 580 patients who underwent surgery for intractable sciatica attributable to pro-lapsed lumbar intervertebral disc from 1986 to 2000 inclusive.

Subjects: The study included a total of 580 patients. Of these seven patients had an operation at two levels, 25 patients had had a primary operation elsewhere and were therefore excluded; four sets of notes remain missing. The total number of primary operations analysed was therefore 558.

Outcome measures: Parameters such as gender, age, level and side of discectomy were entered into a database for analysis. Diagnostic and clinical parameters were also entered; these included the value of the angle of the straight leg raise recorded and absence or presence of neurological deficit (altered sensation, reduced motor power, and absent or diminished reflexes). Operative findings recorded and entered were the type of disc at operation (i. e. protrusion, extrusion and sequestration) and the presence of free cerebrospinal fluid (CSF), however minor, indicating a dural tear.

Results: The total number of primary discectomies was 558 of which 43 went on to require a second operation, giving a revision rate of 7.71%. Of the primary discectomies, 356 were protrusions, 92 extrusions and 110 sequestration. Of the 43 that went onto revision surgery, 35 were protrusions, two extrusion and six sequestration. A significant association was found with primary disc protrusions, this type of disc prolapse was almost three times more likely to go on to need revision surgery compared to extruded or sequestrated discs. Data analysed on primary protrusions showed these patients had a significantly greater straight leg raise angle and reduced incidence of positive neurological findings and so could be identified clinically.

Conclusions: This lead us to conclude that the group of patients with primary protrusions could be selected out and treated conservatively since they are three times more likely to require revision surgery.