We present the case of a previously well 18 year old female who presented with an acute onset swollen painful right ankle with an overlying non-blanching purpuric rash. There were no associated systemic features. Ankle joint aspirate grew Neisseria Meningitides. She was treated with intravenous third generation cephalosporin's and surgical washout of the joint with improvement. Primary meningococcal arthritis (PMA) is rare and mostly associated with the knee joint. Presentation of meningococcal disease in this manner is easily missed or misdiagnosed as gonococcal disease or overlying cellulitis.

Primary meningococcal arthritis is a rare form of septic arthritis. It can be misdiagnosed as an overlying cellulitis or as a gonococcal rash. Physicians should be aware of the possibility of this microorganism presenting as a septic arthritis, and understand the importance of joint aspiration at the centre of diagnosis.

The extension facet angle (EFA) of the medial compartment of the knee has been implicated as a potential mechanical cause for anteromedial knee osteoarthritis.

We developed a novel sagittal plane flexion osteotomy of the medial tibiofemoral compartment. We then performed a cadaveric study to study the effect of the osteotomy on the intra-articular knee pressures under axial load mimicking the stance phase of gait. A Tekscan K400 pressure sensor was inserted submeniscally into the joint and 700N applied using an Instron machine. A topographical map of the pressure areas was then assessed pre- and post-osteotomy for the 10 cadaveric knees specimens.

We found that the intra-articular pressures are greatest in the anteromedial compartment in the native knee and after the osteotomy the area of highest pressure moves posterolaterally spread over a greater surface area.

We conclude that a flexion osteotomy of the medial compartment reduces intra-articular knee pressures concentrated anteromedially in full extension and may be beneficial in patients with an elevated EFA with anteromedial symptoms.

The aim of this study was to investigate the use of large diameter head THR to treat fractured neck of femur, and to demonstrate if this conferred greater stability.

Forty-six (46) independent, mentally alert patients with displaced intracapsular fractures underwent THR. Mean age was 72.1 years. Outcome measures were dislocation, reoperation/ revision rate, Oxford hip score (OHS), Euroqol (EQ-5D) and residential status. Data was collected prospectively, with review being carried out at 3 months and 1 year.

At mean follow-up (12.5 months) there were no dislocations. Reoperation, revision and infection rate were all 0%. Two patients died (4.3%). Mean pre-injury and postoperative OHS were 12.1 and 17.9 respectively. Mean pre-injury and postoperative EQ-5D index scores were 0.97 and 0.83 respectively. Mean postoperative walking distance was 2.5 miles. There were no changes in residential status.

This is the first published series utilizing 36-mm diameter metal-on-metal THR for the treatment of fractured neck of femur. We have demonstrated that it affords patients excellent stability with no recorded dislocations.

The aim of this study was to investigate the use of large diameter head THR to treat fractured neck of femur, and to demonstrate if this conferred greater stability.

46 independent, mentally alert patients with displaced intracapsular fractures underwent THR. Mean age was 72.1 years. Outcome measures were dislocation, reoperation/ revision rate, Oxford hip score (OHS), Euroqol (EQ-5D) and residential status. Data was collected prospectively, with review being carried out at 3 months and 1 year.

At mean follow-up (12.5 months) there were no dislocations. Reoperation, revision and infection rate were all 0%. Two patients died (4.3%). Mean pre-injury and postoperative OHS were 12.1 and 17.9 respectively. Mean pre-injury and postoperative EQ-5D index scores were 0.97 and 0.83 respectively. Mean postoperative walking distance was 2.5 miles. There were no changes in residential status.

This is the first published series utilising 36-mm diameter metal-on-metal THR for the treatment of fractured neck of femur. We have demonstrated that it affords patients excellent stability with no recorded dislocations.

Introduction: Radiolucency in the DeLee and Charnley zone 1 of the acetabulum in the early post operative period is a strong predictor of long-term failure of the cemented acetabulum. There is a wide variety in the acetabular anatomy of patients presenting for total hip replacement. Zone 1 radiolucency is an indicator of the failure of penetration of cement into the relatively hard cortical bone encountered in zone 1. Cement penetration is achieved by adequate preparation, achieving containment and effective pressurisation.

Aim: To use pre operative radiological measurements to predict the risk of radiolucency around the cemented acetabular component post operation.

Hypotheses:

Dysplastic acetabuli are associated with a higher incidence of zone 1 radiolucency.

Materials and Methods: A cohort of 300 patients undergoing cemented THR in our institution was identified. Radiographs performed on the patients pre operatively, post operatively, at first follow up (6 weeks to 3months) and follow up at 1 year were analysed. The following measurements of the native acetabulum were performed: Tonnis grade of osteoarthritis, Crowe grade of dysplasia, acetabular index of depth to width, ACM angle, peak to edge distance, acetabular index of weight bearing zone, centre-edge angle of Widberg, acetabular angle of Sharp, cross over sign and posterior wall sign to assess retroversion, acetabular inclination and anteversion angle. Post operative films were then assessed for the presence of zone 1 keyholes, incidence and degree of radiolucency, cup inclination and anteversion.

Results: Patients with an acetabulum outside the normal range were more likely to have a post operative radiolucency. Radiolucency tended to progress with time. Zone 1 keyholes appeared to terminate this progression. Retroverted and steeply inclined acetabuli demonstrated a higher incidence of radiolucency. A large change in version from the native to prosthetic acetabulum was associated with an increased risk of radiolucency.

Conclusion: Thorough pre operative radiological assessment of the acetabular anatomy allows us to predict patients at high risk of post operative radiolucency. Patients with unsuitable anatomy may be more appropriate for an alternative method of fixation or require different techniques of acetabular preparation or augmentation in order to reduce their risk of loosening of the acetabular component in the long term.

Dislocation is a major concern following total hip replacement (THR) for fractured neck of femur. The aim of this prospective study was to investigate the use of large diameter femoral head uncemented THR to treat fractured neck of femur, and to demonstrate if the improved stability seen in previous clinical situations with these designs, can be used to benefit this difficult subgroup of patients that are particularly prone to dislocation.

Forty-six consecutive independent, active and mentally alert patients with displaced intracapsular fractured neck of femur underwent large diameter head uncemented THR. The mean age of patients was 72.1 years. The outcome measures used were the dislocation rate, reoperation and revision rate, Oxford hip score (OHS), Euroqol (EQ-5D) and residential status.

Clinical and radiological data were available on all 46 patients. At a mean follow-up of 12.5 months there were no dislocations. The reoperation, revision and infection rate were all 0%. Two patients died (4.3%) from unrelated causes. Mean pre- and postoperative OHS were 12.1 and 17.9 respectively. The mean pre- and postoperative EQ-5D index scores were 0.97 and 0.83 respectively. The mean postoperative walking distance was 2.5 miles and there were no changes in residential status.

This is the first published series utilising a 36-mm diameter metal-on-metal THR for the treatment of fractured neck of femur in mobile, independent patients. We have demonstrated that it affords patients excellent stability with no recorded dislocations.

Dislocation is a major concern following THR for fractured neck of femur. The aim of this prospective study was to investigate the use of large diameter femoral head uncemented THR to treat fractured neck of femur, and to demonstrate if the improved stability seen in previous clinical situations with these designs, can be used to benefit this difficult subgroup of patients that are particularly prone to dislocation.

Forty-six consecutive independent, active and mentally alert patients with displaced intracapsular fractured neck of femur underwent large diameter head uncemented THR. The mean age of patients was 72.1 years. The outcome measures used were the dislocation rate, reoperation and revision rate, Oxford hip score (OHS), EuroQol (EQ-5D) and residential status.

Clinical and radiological data were available on all 46 patients. At a mean follow-up of 12.5 months there were no dislocations. There were no reoperations, revisions or infections. Two patients died (4.3%) from unrelated causes. Mean pre- and postoperative OHS were 12.1 and 17.9 respectively. The mean pre- and postoperative EQ-5D index scores were 0.97 and 0.83 respectively. The mean postoperative walking distance was 2.5 miles and there were no changes in residential status.

This is the first published series utilising a 36-mm diameter metal-on-metal THR for the treatment of fractured neck of femur in mobile, independent patients. We have demonstrated that it affords patients excellent stability with no recorded dislocations.

Background: The principal cause of late failure of the cemented acetabular component is aseptic loosening. The acetabulum is a horse shoe of cortico-cancellous bone surrounding a cortical fovea. The cancellous bone becomes denser and less porous peripherally, limiting cement penetration. A radiolucent line in the DeLee and Charnley zone 1 of the acetabulum increases the risk of loosening of the acetabular component by 38.8 times. We propose that the use of 0.5cm keyholes in zone 1 decreases the incidence of zone 1 radiolucency.

Materials and Methods: Two contemporous cohorts of 100 patients were analysed for the incidence of zone 1 radiolucency on the first post operative film. In one cohort, zone 1 keyholes were used and in the other they were not. The films were analysed independently by two blinded investigators. The incidence, length and thickness of any radiolucency were recorded.

Results: The cohort of patients in which zone 1 keyholes were used demonstrated a 9% incidence of any zone 1 radiolucency, 8% were of 1mm width or greater and 2% involved 50% or more of the zone. In the cohort of patients in which zone 1 keyholes were not used the incidence of zone 1 radiolucency was 40% with 29% demonstrating a width of 1mm or greater and 12% affecting 50% or more of the zone.

Conclusions: The use of peripheral keyholes aids penetration of cement into the denser peripheral acetabular bone as demonstrated by decreased rates of post operative zone 1 radiolucency. This decrease in the incidence of early radiolucency should result in lower rates of subsequent loosening of the acetabular component.