Using a computer-based quality assurance program, we analysed peri-operative data on 160 patients undergoing one-stage bilateral hip or knee arthroplasties under regional anaesthesia with routine anaesthetic monitoring and only using peripheral intravenous access for peri-operative safety. We monitored defined intra-operative adverse events such as hypotension, myocardial ischaemia, arrhythmias, hypovolaemia, hypertension and early post-operative complications. We also determined post-operative hip and knee function, and patient satisfaction with different aspects of the anaesthetic management. Those patients undergoing one-stage bilateral arthroplasties were matched according to a cross-stratification which used three variables (American Society of Anesthesiologists’ physical status scoring system, age and joint replaced) to patients undergoing unilateral hip or knee arthroplasties. Serious intra-operative adverse events were, with the exception of intra-operative hypotension, very infrequent in patients undergoing bilateral (nine adverse events) as well as unilateral arthroplasties (five adverse events). Early post-operative complications were also infrequent in both groups. However, the risks of receiving a heterologous blood transfusion (odds ratio 2.5; 95% confidence interval (CI) 1.3 to 5.0, estimated by exact conditional logistic regression) or vasoactive drugs (odds ratio 3.9; 95% CI 2.0 to 7.8) were significantly greater for patients undergoing bilateral operations. Patient satisfaction with anaesthesia was high; all patients who underwent the one-stage bilateral operation would choose the same anaesthetic technique again.

Human bone-marrow mesenchymal stem cells have an important role in the repair of musculoskeletal tissues by migrating from the bone marrow into the injured site and undergoing differentiation. We investigated the use of autologous human serum as a substitute for fetal bovine serum in the ex vivo expansion medium to avoid the transmission of dangerous transfectants during clinical reconstruction procedures.

Autologous human serum was as effective in stimulating growth of bone-marrow stem cells as fetal bovine serum. Furthermore, medium supplemented with autologous human serum was more effective in promoting motility than medium with fetal bovine serum in all cases. Addition of B-fibroblast growth factor to medium with human serum stimulated growth, but not motility. Our results suggest that autologous human serum may provide sufficient ex vivo expansion of human bone-marrow mesenchymal stem cells possessing multidifferentiation potential and may be better than fetal bovine serum in preserving high motility.

We treated 108 patients with a pertrochanteric femoral fracture using either the dynamic hip screw or the proximal femoral nail in this prospective, randomised series. We compared walking ability before fracture, intra-operative variables and return to their residence. Patients treated with the proximal femoral nail (n = 42) had regained their pre-operative walking ability significantly (p = 0.04) more often by the four-month review than those treated with the dynamic hip screw (n = 41). Peri-operative or immediate post-operative measures of outcome did not differ between the groups, with the exception of operation time. The dynamic hip screw allowed a significantly greater compression of the fracture during the four-month follow-up, but consolidation of the fracture was comparable between the two groups. Two major losses of reduction were observed in each group, resulting in a total of four revision operations.

Our results suggest that the use of the proximal femoral nail may allow a faster postoperative restoration of walking ability, when compared with the dynamic hip screw.

We produced large full-thickness articular cartilage defects in 33 rabbits in order to evaluate the effect of joint distraction and autologous culture-expanded bone-marrow-derived mesenchymal cell transplantation (ACBMT) at 12 weeks. After fixing the knee on a hinged external fixator, we resected the entire surface of the tibial plateau. We studied three groups: 1) with and without joint distraction; 2) with joint distraction and collagen gel, and 3) with joint distraction and ACBMT and collagen gel.

The histological scores were significantly higher in the groups with ACBMT collagen gel (p < 0.05). The area of regenerated soft tissue was smaller in the group allowed to bear weight (p < 0.05). These findings suggest that the repair of large defects of cartilage can be enhanced by joint distraction, collagen gel and ACBMT.

The Cambridge Cup has been designed to replace the horseshoe-shaped articular cartilage of the acetabulum and the underlying subchondral bone. It is intended to provide physiological loading with minimal resection of healthy bone.

The cup has been used in 50 women with displaced, subcapital fractures of the neck of the femur. In 24 cases, the cup was coated with hydroxyapatite. In 26, the coating was removed before implantation in order to simulate the effect of long-term resorption.

The mean Barthel index and the Charnley-modified Merle d’Aubigné scores recovered to their levels before fracture. We reviewed 30 women at two years, 21 were asymptomatic and nine reported minimal pain. The mean scores deteriorated slightly after five years reflecting the comorbidity of advancing age. Patients with the hydroxyapatite-coated components remained asymptomatic, with no wear or loosening. The uncoated components migrated after four years and three required revision. This trial shows good early results using a novel, hydroxyapatite-coated, physiological acetabular component.

We have evaluated the functional, clinical and radiological outcome of patients with simple and complex acetabular fractures involving the posterior wall, and identified factors associated with an adverse outcome.

We reviewed 128 patients treated operatively for a fracture involving the posterior wall of the acetabulum between 1982 and 1999. The Musculoskeletal Functional Assessment and Short-Form 36 scores, the presence of radiological arthritis and complications were assessed as a function of injury, treatment and clinical variables.

The patients had profound functional deficits compared with the normal population. Anatomical reduction alone was not sufficient to restore function. The fracture pattern, marginal impaction and residual displacement of > 2 mm were associated with the development of arthritis, which related to poor function and the need for hip replacement. It may be appropriate to consider immediate total hip replacement for patients aged > 50 years with marginal impaction and comminution of the wall, since 7 of 13 (54%) of these required early hip replacement.

We studied 217 patients with an unstable trochanteric or subtrochanteric fracture who had been randomly allocated to treatment by either internal fixation with a standard Gamma nail (SGN) or a Medoff sliding plate (MSP, biaxial dynamisation mode). Their mean age was 84 years (65 to 99) and they were reviewed at four and 12 months after surgery. Assessments of outcome included general complications, technical failures, revision surgery, activities of daily living (ADL), hip function (Charnley score) and the health-related quality of life (HRQOL, EQ-5D).

The rate of technical failure in patients with unstable trochanteric fractures was 6.5% (6/93) (including intra-operative femoral fractures) in the SGN group and 5.2% (5/96) in the MSP group. In patients with subtrochanteric fractures, there were no failures in the SGN group (n = 16) and two in the MSP group (n = 12). In the SGN group, there were intra-operative femoral fractures in 2.8% (3/109) and no post-operative fractures. There was a reduced need for revision surgery in the SGN group compared with the MSP group (8.3%; 9/108; p = 0.072). The SGN group also showed a lower incidence of severe general complications (p < 0.05) and a trend towards a lower incidence of wound infections (p = 0.05). There were no differences between the groups regarding the outcome of ADL, hip function or the HRQOL. The reduction in the HRQOL (EQ-5D_indexscore) was significant in both groups compared with that before the fracture (p < 0.005).

Our findings indicate that the SGN showed good results in both trochanteric and subtrochanteric fractures. The limited number of intra-operative femoral fractures did not influence the outcome or the need for revision surgery. Moreover, the SGN group had a reduced number of serious general complications and wound infections compared with the MSP group. The MSP in the biaxial dynamisation mode had a low rate of failure in trochanteric fractures but an unacceptably high rate when used in the biaxial dynamisation mode in subtrochanteric fractures.

The negative influence of an unstable trochanteric or subtrochanteric fracture on the quality of life was significant regardless of the surgical method.

Over the past 40 years, the management of displaced fractures of the acetabulum has changed from conservative to operative. We have undertaken a meta-analysis to evaluate the classification, the incidence of complications and the functional outcome of patients who had undergone operative treatment of such injuries.

We analysed a total of 3670 fractures. The most common long-term complication was osteoarthritis which occurred in approximately 20% of the patients. Other late complications, including heterotopic ossification and avascular necrosis of the femoral head, were present in less than 10%. However, only 8% of patients who were treated surgically needed a further operation, usually a hip arthroplasty, and between 75% and 80% of patients gained an excellent or good result at a mean of five years after injury. Factors influencing the functional outcome included the type of fracture and/or dislocation, damage to the femoral head, associated injuries and co-morbidity which can be considered to be non-controllable, and the timing of the operation, the surgical approach, the quality of reduction and local complications which are all controllable. The treatment of these injuries is challenging. Tertiary referrals need to be undertaken as early as possible, since the timing of surgery is of the utmost importance. It is important, at operation, to obtain the most accurate reduction of the fracture which is possible, with a minimal surgical approach, as both are related to improved outcome.

Although the importance of sound statistical principles in the design and analysis of data has gained prominence in recent years, biostatistics, the application of statistics to the analysis of biological and medical data, is still a subject which is poorly understood and often mishandled. This review introduces, in the context of orthopaedic research, the terminology and the principles involved in simple data analysis, and outlines areas of medical statistics that have gained prominence in recent years. It also lists and provides an insight into some of the more common errors that occur in published orthopaedic journals and which are frequently encountered at the review stage in papers submitted to the Journal of Bone and Joint Surgery.