It has been suggested that an increased posterior tibial slope (PTS) and a narrow notch width index (NWI) increase the risk of anterior cruciate ligament (ACL) injury. The aim of this study was to establish why there are conflicting reports on their significance. A total of fifty patients with a ruptured ACL and 50 patients with an intact ACL were included in the study. The group with ACL rupture had a statistically significantly increased PTS (p < 0.001) and a smaller NWI (p < 0.001) than the control group. When a high PTS and/or a narrow NWI were defined as risk factors for an ACL rupture, 80% of patients had at least one risk factor present; only 24% had both factors present. In both groups the PTS was negatively correlated to the NWI (correlation coefficient = -0.28, p = 0.0052). Using a univariate model, PTS and NWI appear to be correlated to rupture of the ACL. Using a logistic regression model, the PTS (p = 0.006) and the NWI (p < 0.0001) remain significant risk factors. From these results, either a steep PTS or a narrow NWI predisposes an individual to ACL injury. Future studies should consider these factors in combination rather than in isolation.

Aim: To develop a flexion jig that would reliably hold the post-op knee in fixed flexion for a defined time period and determine its influence on peri-operative blood loss, transfusion, pain, and complications (specifically nerve palsy)following TKA.

Methods/Results: A previous study in this department showed immediate postoperative flexion to significantly reduce blood loss following TKR. Following this study, time in flexion was increased to 12 hours in an attempt to further reduce blood loss., some patients then developed a painful lower limb nerve palsy. This palsy was caused by pressure from the jig in the popliteal fossa/calf on nerves. The design of the jig was altered to remove pressure from these areas. Because of this design change, we were unsure whether the new jig would have the same blood saving effect, necessitating a new study.

This prospective randomised controlled trial recruited 420 patients into 3 equal groups: extension, 3 & 6 hrs flexion.

This trial found a significant reduction in blood loss(12%, p=0.006) and length of stay(1/2 day, p=0.006) in the 6 hour flexion group, compared the extension group.

There was no significant difference in pain or complication rates (excluding nerve palsy).

2 patients in the 6 hour group had postoperative nerve palsy, however, this palsy was sensory only and markedly different to that found previously. Although the palsy rate in this study is similar(1.4%) to quoted literature rates (1.3%) for TKA, it is difficult to know if the jig was the cause of palsy as the there was a difference between those caused by the old metal jig (painful) and those in this study (sensory loss only).

Conclusion: The results of this study show post-op flexion for 6 hours to significantly reduce perioperative blood loss. Palsy was reduced to match rates as quoted in the literature.

Between April 1992 and July 2005, 310 posterior lip augmentation devices were used for the treatment of recurrent dislocation of the hip in 307 patients who had received primary total hip replacements (THRs) using Charnley/Charnley Elite components with a cemented acetabulum. The mean number of dislocations before stabilisation with the device was five (1 to 16) with a mean time to this intervention from the first dislocation of 3.8 years (0 days to 22.5 years). The mean age of the patients at this reconstruction was 75.4 years (39 to 96).

A retrospective clinical and radiological review was carried out at a mean follow-up of six years and nine months (4.4 months to 13 years and 7 months). Of the 307 patients, 53 had died at the time of the latest review, with a functioning THR and with the posterior lip augmentation device in situ. There were four revisions (1.3%), one for pain, two for deep infection and one for loosening of the acetabular component. Radiolucent lines around the acetabular component increased in only six cases after insertion of the device which was successful in eliminating instability in 302 patients, with only five further dislocations (1.6%) occurring after its insertion.

Current methods for restoring or preserving limb length following total hip arthroplasty are anatomically inaccurate, as they do not consider acetabular and femoral height independently. In order to address this, we present and evaluate a technique that uses the transverse acetabular ligament to control the vertical height of the acetabular component and a caliper that controls the vertical placement of the femoral component within the femoral canal. Limb lengths were measured in 200 patients who had undergone primary total hip arthroplasty using this technique. Using this method, 94% had a post-operative limb length inequality that was 6 mm or less when compared to the normal side (average +0.38 mm). The maximum measured limb length inequality was ± 8 mm.

Background: The positioning of the acetabular component is of critical importance in total hip arthroplasty. Due to the orientation of the acetabulum and limitations of observation imposed at the operative site mal-positioning is common. We believe that by utilising the transverse acetabular ligament (TAL) and acetabular labrum, we are able to anatomically position our cup. In this study, we evaluate the correlation between placement of the acetabular component by reference to the TAL and the acetabular labrum with the taught safe zones for cup placement.

Method: 7 embalmed hips were studied. Following disarticulation the labrum and TAL were digitised and their plane was calculated. Orientation of cup placement in this plane was calculated from a pre-dissection pelvic CT.

Results: The plane of the labrum/TAL varied between 5–26° of anteversion and 32–59° of inclination. Interob-server differences in acetabular cup placement based on the TAL/labral plane indicate reasonable coherence. Almost all components were inside the documented “safe zone” 0–40° of anteversion and 30–55° of inclination of placement.

Conclusion: The acetabular labrum and TAL form a plane that reflects the documented “safe zones” for acetabular component placement. We feel that this plane allows a surgeon to determine optimal patient specific acetabular component placement, irrespective of patient position.