Method

286 patients underwent total hip arthroplasty with a cemented titanium femoral implant (Ultima, Johnson & Johnson) between July 1995 and July 2001. The acetabular component was either a porous coated cup or a cemented all-polyethylene cup. A 28mm cobalt chromium head was used in all patients. Patients were prospectively evaluated with clinical examination, Harris hip scores and radiographic assessment. Analysis of the data was performed.

Introduction

Previous studies comparing cruciate retaining (CR) and cruciate sacrificing - posterior stabilised (PS) TKRs have failed to demonstrate a difference in outcomes based on numbers of patients recruited.

This large study compares clinical outcomes in groups having PS and CR TKR and reports the results at 1 and 2 years post-operatively.

Summary: This study compares the outcomes of a large series of 683 cruciate sacrificing (PS) and cruciate retaining (CR) TKRs at minimum 2 years follow-up. Patients with a PS component showed a greater improvement in the pain and knee components of the American Knee Society Score at both 1 and 2 years post-operatively and also demonstrated a greater improvement in knee flex-ion at both time points.

Introduction: Excellent clinical results have been reported with both PS and CR TKR designs. A number of randomised trials comparing the two techniques have failed to demonstrate a difference in outcomes based on the numbers of patients recruited.

It is hypothesised that cruciate retention in total knee arthroplasty may result in improved kinematics of the knee by maintaining the femoral rollback seen in the normal knee, resulting in improved function. This study compares clinical outcomes in groups having PS and CR total knee arthroplasty and report the results at 1 and 2 years post-operatively.

Methods: A total of 683 patients undergoing TKR surgery were consecutively enrolled in a prospective multi-centre study with 2 arms. In the first arm patients receiving a PS component were randomised to receive either a mobile bearing (176 patients) or fixed bearing (176 patients) implant. In the second arm, patients receiving a CR component were randomised to receive either a mobile bearing (161 patients) or fixed bearing (170 patients) implant. All patients were assessed pre-operatively and at one and two years postoperatively using standard tools (Oxford, AKSS, Patellar Score) by independent nurse specialists. The data from the 2 arms of the trial were then analysed to compare differences between PS and CR implants.

Results: Patients with a PS component showed a greater improvement in the pain component of the AKSS at 1 year (p=0.0003) and at 2 years (p=0.0085) post-op.

Patients with a PS also showed a greater improvement in the AKSS knee score at 1 (p=0.0001) and 2 (p=0.001) years.

Knee flexion improvement was also greater in the PS group at 1 (p=0< 0.0001) and 2 (p=0.0035) years.

PS knees also achieved better outcomes in these variables in the mobile and fixed subgroups.

There were no other significant differences in the scores between the two groups at any stage.

Conclusion: This study reports on a large prospective multi-centre series of PS and CR TKRs. Improvements in pain and knee components of the AKSS score and knee flexion at both 1 and 2 years follow-up were greater in PS knees. Although this difference was statistically significant, differences in real terms were relatively small.

Background: Cemented and cementless fixations of acetabular components in total hip arthroplasty are routine practice with inherent advantages and disadvantages. The aim of our prospective randomized study was to compare the clinical and radiographic results of cementless porous-coated cobalt chromium acetabular component with cemented all-polyethylene acetabular component in total hip arthroplasty.

Methods: Three hundred patients were randomized to receive a cementless hemispherical cobalt chromium porous-coated no-hole acetabular component (group 1) or cemented all-polyethylene acetabular component (group 2) with an identical cemented femoral stem and 28mm cobalt-chromium head. Patients were evaluated clinically with Harris Hip Scores (HHS) and radiographically. Analysis of both intention-to-treat groups was performed.

Results: Group 1 had 128 patients (55 male, 73 female) with average age of 70.3 years. Group 2 had 147 patients (63 male, 84 female) with average age of 71.2 years. Average follow-up was 9.5 years (1.03–13.23). The median follow-up was 10 years. 25 patients were excluded from analysis for reasons including unfit for surgery (2), operation cancelled (2), missing data (8) and non-study device (10). Average preoperative HHS improved from 34.4 and 34.5 to 80 and 82.5 postoperatively in group 1 and 2 respectively. There was no statistically significant difference between the average HHS of the two groups (p=0.449) at last follow-up. There were 7 revisions in group 1 [infection (2), cup migration (2), aseptic loosening (1), slipped cup (1) and fractured liner (1)]. 11 patients had revision in group 2 [aseptic loosening (8) and recurrent dislocations (3)]. Revision rate between the two groups was not statistically significant (p=0.465). 10-year survivorship was 93.8%; and 86.6%; for group 1 and 2 respectively. No statistically significant difference was noted for prognostic factors like gender (p=0.006), body mass index (p=0.433), age (p=0.657) and surgical approach (p=0.004) for the two groups. Prognostic factors like gender (male, p=0.006) and surgical approach (posterior, p=0.004) were noted to be significant but body mass index (p=0.433) and age (p=0.657) had no statistical significance. Bootstrapping analysis for the two groups (p-value calculations N=3000) showed a significant p-value for 19 and not significant p-value for 2981 calculations. 4 porous coated cups and 29 all-polyethylene cups had radiolucencies. None of the porous-coated cups had expansile osteolysis.

Conclusions: The results from our study indicate that patients with a cemented all-polyethylene cup and cementless porous coated cup have similar long term outcomes. In patients over 75 years cemented cups have excellent results (100% survivorship at 10 years).

Introduction: Surgery and the use of pneumatic tourniquets lead to an increase in the activity of the fibrinolytic system, which in turn may accentuate the blood loss during knee arthroplasty. Drugs that inhibit the fibrinolytic system may thus be used to reduce blood loss. Tranexamic acid (TA) acts by binding to one of the enzymes at the start of the coagulation cascade, so inhibiting the fibrinolytic system. A concern is that this inhibition may have the side effect of increasing thromboembolic disease, a common complication of joint replacement surgery. We aim to confirm the reductions in blood loss and to assess the impact of TA usage on clinical and sub-clinical DVT.

Method: We performed a prospective, randomised, double blind, controlled trial, using patients due to undergo primary unilateral total knee arthroplasty. Patients were randomised to receive either 15mg/kg of tranexamic acid or a similar volume of normal saline at the time of cementing of the prosthesis. Perioperative blood loss was recorded and patients were screened for DVT with duplex ultrasound assessment of both legs on the fifth post-operative day.

Results: A statistically significant (p=0.006) decrease in blood loss in the early post operative period was noted in the group receiving tranexamic acid. This was not associated with a significant difference in total blood loss (p=0.55) or in transfusion requirements. There was no evidence of DVT in either group on duplex ultrasound screening of the lower limbs.

Interpretation: One injection of 15mg/kg of tranexamic given at the time of cementing the prosthesis in total knee arthroplasty, before deflation of the tourniquet, significantly decreases the amount of blood loss in the early post operative period. The treatment was not associated with an increase in thromboembolic complications.

Ten epiphyses in seven children underwent fixed-rate distraction of 0.25 mm twice daily in an attempt to achieve percutaneous leg lengthening by chondrodiatasis. The forces generated across the growth plate were recorded by means of strain gauges incorporated into the distractors. All epiphyses fractured before 33 days of lengthening. An average gain of 6.75 cm was achieved. Epiphyseal distraction at the lower femur produced many complications, but at the upper tibial epiphysis planned lengthening was achieved, with excellent bone production and few complications.

It has been shown that raised intracapsular pressure causes avascular necrosis of the femoral head in experimental animals, but the relevance of this to clinical fractures of the femoral neck is controversial. We have studied 19 patients with intracapsular fractures of the femoral neck by pressure measurement and by ultrasonography to demonstrate capsular distension. The intra-articular pressure in Garden Grade I and II fractures averaged 66.4 mmHg with a maximum of 145 mmHg. In 10 Garden Grade III and IV fractures the average pressure was 28 mmHg with a maximum of 65 mmHg. Most of the recorded intracapsular pressures were high enough to have caused possible vascular embarrassment, and it is suggested that early decompression of the haemarthrosis should be considered.

Five patients known to be HIV (human immunodeficiency virus)-positive--that is, susceptible to AIDS--presented with symptoms initially thought to be indicative of lumbar disc lesions. Signs of nerve root or cauda equina compression were found in all five patients. Lumbar radiculography and, in one patient, computerised tomography produced no evidence of compressive pathology. We recommend that orthopaedic surgeons exercise caution in diagnosing nerve root compression in patients who may be HIV-positive.