Aims

This study describes the use of the Masquelet technique to treat segmental tibial bone loss in 12 patients.

A statement of the purposes of the study and background:

Merely publishing clinical guidelines is insufficient to ensure their implementation in clinical practice. We aimed to clarify the decision-making processes that result in the delivery of particular treatments to patients with low back pain (LBP) in primary care and to examine clinicians' perspectives on the National Institute for Health and Care Excellence (NICE) clinical guidelines for managing LBP in primary care.

Introduction: Screws placed in the fibula do not have a satisfactory purchase during internal fixation of an osteoporotic ankle fracture. Tibia-pro-fibula screws that extend from the fibula into the distal tibial metaphysis provide additional purchase. The purpose of this study is to investigate if purchase of these screws can be enhanced further by injecting calcium sulfate and calcium phosphate composite graft in the drill holes prior to insertion of the screws.

Methods: Bone density was quantified using DEXA scan in paired cadaver legs. One leg from each pair was randomly selected for injection of composite graft into screw holes before insertion of the screws. Two screws were inserted through the fibula into the distal tibial metaphysis in each leg, at the level of the syndesmosis under fluoroscopy in a standardized fashion using a jig.

The screws were pulled out using a materials testing machine. Stiffness, force, displacement, and energy required were recorded.

Results: After testing 4 pairs of cadaver legs, a statistically significant difference was noted in displacement, failure load, and failure energy between augmented and non-augmented screws, with the augmented screws being considerably stronger. Of the two screws the distal, when compared to the proximal one, required more displacement, higher force and energy to fail whether augmented with composite graft or not.

Conclusion: Screws augmented with composite graft provide significantly greater purchase in an osteoporotic distal tibial metaphysis than non-augmented screws.

Clinical relevance: Use of composite graft to augment purchase of the screws inserted in the distal tibial metaphysis may enhance the stability of the internal fixation of an osteoporotic ankle fracture. This will enable early weight-bearing mobilization and return to function which is important in elderly patients.

Introduction: With the rising number of primary hip arthroplasties performed each year, patient selection criteria is becoming increasingly pertinent. There is growing concern that patients with a high body mass index (BMI) have worse outcomes following hip replacement surgery. However the evidence base is equivocal.

Our aim is to assess whether BMI has an impact on clinical and radiological outcomes of primary total hip arthroplasties

Methods: This is a prospective study of 92 patients, undergoing primary total hip arthroplasty, recruited from two hospitals. Data was collected by the operating surgical team and independent physiotherapists at the preoperative assessment clinic, intraoperatively and at six weeks post-operative follow up.

BMI was recorded. Patients were divided into 2 groups: those with a BMI less than 30 (considered nonobese) and those 30 or above (obese).

Outcomes assessed included blood loss and requirement blood transfusion, fat thickness, operation duration, complications and surgeon’s perception of the difficulty of operation (scored on a VAS). In addition functional capacity was assessed using the Oxford Hip scores pre and post-operatively. Radiographs were scored independently according to Dorr and Barrack.

Results: Of our 92 patients, 36 were obese and 56 were non-obese. There was no significant difference found in blood loss, blood transfusion requirements, operation duration and complications between the two groups, With regards to the Oxford Hip scores, the obese patients had greater differences between their pre- and post-operative scores but this difference was not significant (p=0.09). We found a significant difference (p=0.003) in surgeons’ perception of the difficulty of operation with VAS scores for obese patients being higher than non-obese patients. Our Dorr and Barrack scores revealed no significant difference in radiological outcome between our two groups.

Conclusion: Our study would suggest that obese patients do not have worse outcomes following primary total hip arthroplasty than non-obese patients.

Introduction and aims: Increasingly the accurate reconstruction of the hip in total hip arthroplasty is planned using pre-operative pelvic radiographs. The accuracy of reconstruction is assessed using post-operative pelvic radiographs. This study defines significant variations in the offset, hip joint centre and femoral head centre-trochanteric height relations in normal radiographs.

Method: One hundred standard normal pelvic radiographs were examined based on a defined criterion. The medial offset, the vertical height of hip joint centre with reference to the ischial tuberosity and the femoral head centre-trochanterc height relation were measured for both hips. The differences in measurements were evaluated to determine the normal variation in offset and the hip joint centre. The relationship of the femoral head centre to the tip of the greater trochanter was determined.

Results: On average, the right hip and left hip differed by 2.54mm in their offset .The standard deviation of differences was 2.31. Therefore the offset of one hip will predict the offset of the other hip to within 4.62mm, with 95% accuracy. If the reconstructed hip has an offset to within + 4.62 to – 4.62mm of the contra lateral side, then the offset should be considered to be reconstructed as normal. The average difference in height of the hip joint centres of right hip from left hip with reference to bi-ischial line was found to be 3.49mm. The standard deviation of differences was 3.15. Therefore the hip joint centre height measured in one hip will predict the hip joint centre height of the opposite hip to within 6.3mm with 95% accuracy. Thus the hip joint centre height of one hip may differ from the opposite hip by 6.3mm in normal individuals. The tip of greater trochanter was on average 8mm higher than the centre of rotation of the femoral head. The greater trochanter was not at the same level as the femoral head centre as commonly believed.

Conclusion: This study demonstrates considerable variation in the medial offset and the hip joint centre location on pelvic wall. The femur head centre is lower than commonly assumed. These factors should be taken into account when pre-operative planning using pelvic radiographs and assessing the quality of the post-operative reconstruction.

Total knee replacement (TKR) is intended to satisfy patients rather than surgeons. The latter could be more optimistic when they assess the outcome of their own operations. We envisage that there is a variation between patients’ own assessment and those of surgeons. This study reviewed long-term results of TKR and compared between patients’ assessment and surgeon’s assessment.

Four hundred and six TKR were performed between 1980 and 1994 in a DGH by one surgeon using single knee prosthesis. The follow up was up to 14 years (mean 7.2). Clinical assessment was done by the surgeon in out patient clinic and was compared to the patients’ assessment, which was done through a confidential postal questionnaire (PQ).

Response rate to PQ was 84 %. There was an obvious discrepancy in reporting pain and patients’ satisfaction between the two methods of assessment however there was similarity in other parameters. Surgeon rated satisfaction more highly and patients reported more pain in PQ. In this study revision rate was 4 %, infection 1.7 %, instability 1.4 % and patellar pain 20 %.

There is a variation between patients’ own assessment and those of surgeons. For accurate assessment of the outcome of TKR we recommend the use of postal questionnaire alongside clinical assessment.

Ulceration of the lower leg is considered to be a ‘hard’ clinical endpoint of venous thrombosis. Total knee replacement (TKR) is a significant risk factor for venous thrombosis of the leg and therefore potentially for ulceration.

We sent a postal questionnaire to 244 patients at a minimum of five years after TKR enquiring about the development of ulceration since their TKR. The overall incidence of ulceration, both active and healed, was 8.67% which is similar to that in the age-matched general population (9.6% to 12.6%), as was the prevalence of active ulceration. We also identified no clear association between venographically-confirmed postoperative deep-venous thrombosis (DVT) and the incidence and prevalence of ulcers at five years. We suggest that after TKR DVT is not a significant risk factor for ulceration of the leg and that perioperative chemical thromboprophylaxis may not be justified on these grounds.

Survivorship analysis is a useful way of expressing the long-term results of joint replacement: it provides a means of comparing the life span of one type of prosthesis with another. However, such studies should include a full life-table and the confidence intervals for the survival rates at given times. At least 40 surviving prostheses are required to provide reliable results.

Maquet's line passes from the centre of the femoral head to the centre of the body of the talus. The distance of this line from the centre of the knee on a long-leg radiograph provides the most accurate measure of coronal alignment. Malalignment causes abnormal forces which may lead to loosening after knee replacement. We report a series of 115 Denham knee replacements performed between 1976 and 1981 using the earliest design of components, inserted with intramedullary guide rods. Patients were assessed clinically and long-leg standing radiographs were taken before operation, soon after surgery and up to 12 years later. In two-thirds of the knees (68%) Maquet's line passed through the middle third of the prosthesis on postoperative films and the incidence of subsequent loosening was 3%. When Maquet's line was medial or lateral to this, an error of approximately +/- 3 degrees, the incidence of loosening at a median period of eight years was 24%. This difference is highly significant (p = 0.001). Accurate coronal alignment appears to be an important factor in prevention of loosening. Means of improving the accuracy of alignment and of measuring it on long-leg radiographs are discussed.

The statistical quality of 103 original articles published in The Journal of Bone and Joint Surgery (British Volume) in 1984 was assessed. Some papers were found to be deficient: thus, it was not always clear how series were selected and sometimes neither the data nor the results were clearly presented. Sample sizes were frequently inadequate for the conclusions reached and statistical techniques should have been used more frequently. A majority of papers were descriptions of case series for which no comparative data were made available. It is suggested that collaborative research would best advance knowledge about the relative benefits of various managements, and that statistical advice could make a substantial contribution.