Purpose: Kinematic studies have shown that patients with a total hip arthroplasty (THA) walk with different gait characteristics compared to normal subjects. This abnormal gait might result from difficulties restoring the normal hip anatomy and biomechanics with THA. Surface replacement arthroplasty (SRA) facilitates leg length management and reconstruction of the normal anatomy of the proximal femur, allowing potential improvements in muscle power, proprioception and hip stability compared to THA.

Method: Patients suffering from advanced hip joint disease were randomised to receive an uncemented metal-metal THA or metal-metal SRA. A group of patients from this study were evaluated pre operatively, at 6 months and one year post operatively at a gait laboratory. A VICON system with 8 cameras, platform (AMTI) and surface electromyograph (Motion Lab) were used. Articular and muscle power and work characteristics of the hip, knee and ankle were analysed with different tasks. Postural stability (e.g. distance between the mass centre and pressure centre) in the standing position will serve to differentiate the 2 groups. Other specific tests, such as the hop test, the step test and the TUG test, were performed.

Summary of Results: Thirty randomised patients were evaluated. The results will be presented and discussed.

Discussion: Considering the strong interest of patients and surgeons for the potential functional benefits of surface replacement arthroplasty, it is necessary to determine scientifically how it compares with the standard of care (THA). Patient age, weight, sex and pre operative function have a strong influence on the post operative function. Thus, a prospective randomised study is mandatory to obtain valid results.

Significance: We strongly believe that this subject warrants special attention considering the possible benefits associated with this technique in the young adult with hip osteoarthitis.

Introduction and Aims: Osteoporotic fractures, especially hip fractures, represent a major health problem in terms of morbidity, mortality and cost. Since the availability of new treatments for osteoporosis, a better understanding of the disease is needed to define the indications for treatment.

Method: A descriptive study of osteoporotic fractures and the evaluation of the relative risk of hip fracture following a minor fracture were done on a population aged 45 years old and older from 1980 to 1997 (2.5 million individuals, 1997).

Results: During the follow-up period, 220,120 fractures (hip, wrist, proximal humerus and ankle) were recorded. The incidence rate of fractures was stable over time. The wrist fracture was the most frequent (42.2%), followed by the hip fracture (32.5%). Although the proportions of fracture sites were similar for both sexes, 75% of the fractures occurred in females. The mortality rate one year after a hip fracture is increased by 14–27% for men and 9–13% for women after 60 years of age. Men and women aged 45 years old and older have a risk for hip fracture after a humerus or a wrist fracture of 2.3–17.3 time the risk of people without previous fracture.

Conclusion: Wrist and humerus fractures represent a major risk for future hip fracture, prevention of hip fracture should be revaluated regarding these new data and all these patients should be evaluated for osteoporosis and receive the appropriate treatment.

Introduction and Aims: Vertical acetabular cup positioning is an important technical aspect in total hip arthroplasty. It has been reported that acetabular component malpositioning is associated with an increased risk of dislocation, limited range of motion and impingement. A high vertical acetabular angle is correlated positively with premature polyethylene wear, osteolysis and early aseptic loosening in metal-polyethylene and ceramic-ceramic interface.

Method: To evaluate the potential benefit of using an inclinometer in vertical acetabular cup positioning, 96 patients were randomised to have their acetabular cup insertions done with an inclinometer or by visuo-spatial perception alone. The surgeries were performed by five hip surgeons.

Results: The precision of the acetabular vertical angles averaged 43 degrees +/-6.7 by visuo-spatial perception alone and 44 degrees +/-6.8 with the inclinometer. With the inclinometer and by visuo-spatial perception respectively, 12.8% and 9.3% of the cups were outside a safe angle range of 35–54 degrees. The standard deviation was +/-4.9 degrees for the inclinometer and +/-4.7 degrees for the visuo spatial perception method.

Conclusion: The use of an inclinometer is as precise as the visuo spatial perception of a hip surgeon. Positioning the cup with the inclinometer did not reduce the variability or improve the precision of the vertical acetabular position during total hip arthroplasty, suggesting it is not an essential adjunct in the clinical practice of hip surgeons. However, the inclinometer might be a valuable tool for surgeons performing a low volume of hip surgery.

Introduction and Aims: Because of its superior tribologic properties and bioinert composition, alumina-alumina (AL-AL) bearing surfaces are proposed to improved survival of total hip arthroplasty (THA), but previously reported early complications prevented widespread use of this material. This study compares early results and complication with Ceraver Metal-Polyethylene (M-P) and AL-AL THA.

Method: One hundred forty-eight Ceraver hybrid THA in patients less than 70 years old were randomised to M-P or AL-AL bearing surfaces. We present the clinical and radiological results for patients two to seven years after their surgery.

Results: No significant difference was found on WOMAC and Merle D’Aubigné Postel scores. No specific complication associated with alumina components like fracture or malpositioning of the acetabular insert were observed in this study. Documented complications were: infection four AL-AL /two M-P; dislocation one AL-AL /four M-P; and heterotopic ossification 47% AL-AL /24% M-P. No aseptic loosening was observed.

Conclusion: Ceraver AL-AL bearing surfaces give early clinical and radiological results similar to M-P. Our results are in accordance with studies suggesting that AL-AL have a potential to become good bearing surfaces in THA in the young patients.

Introduction and Aims: Although many analgesia modalities have been tried, total knee arthroplasty remains a painful procedure and parenteral narcotics still play a major role in post-operative pain control. We want to know if peri-articular large dose injection of local anaesthetics reduces narcotics administration and their side effects.

Method: Thirty-six patients undergoing a total knee replacement were randomised to two treatment groups. The experimental group received peri-articular large dose infiltration of Ropivacaine (local anaesthetic) during surgery and on day one after surgery via an intra-articular catheter. The pain control was completed with a self-delivering morphine pump. The control group received the morphine pump alone. The therapists recording post-op data were blind to the treatment group. Narcotics consumption, pain control, medication side effects, complications, range of motion and patient satisfaction were monitored. Ropivacaine serum levels were measured in the early post-operative period.

Results: Although satisfaction was very high in both groups, morphine consumption was significantly lower for the infiltration group: 29 mg/24h compared to 51 mg/24 (p< 0.01) and 47 mg/40h compared to 71 mg/40h (p< 0.04). The post-operative pain evaluated with visual analogue scale (0–10) was reduced significantly on the day of surgery 2.6 vs 5.0 (p< 0.04) and at exercise on day one post-op: 4.9 vs 7.0 (p< 0.01). There was no significant difference in post-operative range of motion at five days post-op. The surgical time was increased significantly by 18 minutes in the infiltration group 126 vs 108 minutes (p< 0.05). Complication rate was not significantly different for both groups (infiltration vs control): nausea symptoms 2.2h/48h vs 5.4h/48, confusion two subjects in each group, constipation three subjects in each group and one deep vein thrombosis per group. No complication was related to the addition of the infiltration of the local anaesthetics and the serum levels were in a safe range.

Conclusion: This peri-operative local anaesthetics infiltration protocol offer many benefits for the patients undergoing a total knee arthroplasty. It is improving the pain control, reducing the amount of narcotics consumption and is a safe procedure.

Disturbance of lung function during hip arthroplasty surgery is well recognised and, until now, only reported secondary to femoral instrumentation. We present a case report of per-operative acute pulmonary embolism that followed the insertion of an intereference fit acetabular component during hip resurfacing arthroplasty. A subsequent prospective study of per-operative lung function revealed that 9 out of 10 patients experienced an increase in pulmonary shunt value of up to 30% following socket insertion. The changes in shunt values were significant (p=0.009). We have highlighted for the first time the significant physiological disturbances that occur upon insertion of solid interference fit acetabular components, which although apparently transient, may prove life threatening.

Introduction: The excellent results obtained with metal-polyethylene (M-P) bearing surfaces in total hip arthroplasty (THA) are still limited by the production of polyethylene wear debris, osteolysis and aseptic loosening. Because of its superior tribologic properties and biologically inert composition, alumina-alumina (AL-AL) bearing surfaces are proposed to improved survival of THA but previously reported early complications prevented widespread use of this material.

Aim: To compare the early results and complications with Ceraver M-P and AL-AL THA.

Methods: One hundred and thirty-eight Ceraver hybrid THAs in patients less than 70 years old were randomised to M-P or AL-AL bearing surfaces. We present the clinical and radiological results for patients followed-up from six to 48 months.

Results: No significant difference was found on W.O.M.A.C. and Merle D’ Aubigné Postel scores. No specific complication associated with alumina components like fracture or malpositioning of the acetabular insert were observed in this study. Documented complications were: infection 3 AL-AL / 0 M-P; dislocation 1 AL-AL / 4 M-P; and heterotopic ossification 47% AL-AL / 24% M-P. No aseptic loosening was observed.

Discussion and Conclusion: Ceraver AL-AL bearing surfaces gave early clinical and radiological results similar to M-P. Our results were in accordance with studies suggesting that AL-AL has the potential to become the bearing surfaces of choice in THA in the young patients.