We used interconnected porous calcium hydroxyapatite ceramic to bridge a rabbit ulnar defect. Two weeks after inducing the defect we percutaneously injected rabbit bone marrow-derived mesenchymal stromal cells labelled with ferumoxide. The contribution of an external magnetic targeting system to attract these cells into the ceramic and their effect on subsequent bone formation were evaluated.

This technique significantly facilitated the infiltration of ferumoxide-labelled cells into ceramic and significantly contributed to the enhancement of bone formation even in the chronic phase. As such, it is potentially of clinical use to treat fractures, bone defects, delayed union and nonunion.

We compared 55 consecutive total hip replacements performed on 53 morbidly obese patients with osteoarthritis with a matched group of 55 total hip replacements in 53 non-obese patients. The groups were matched for age, gender, prosthesis type, laterality and preoperative Harris Hip Score. They were followed prospectively for five years and the outcomes were assessed using the Harris Hip Score, the Short-form 36 score and radiological findings.

Survival at five years using revision surgery as an endpoint, was 90.9% (95% confidence interval 82.9 to 98.9) for the morbidly obese and 100% for the non-obese patients. The Harris Hip and the Short-form 36 scores were significantly better in the non-obese group (p < 0.001). The morbidly obese patients had a higher rate of complications (22% vs 5%, p = 0.012), which included dislocation and both superficial and deep infection.

In light of these inferior results, morbidly obese patients should be advised to lose weight before undergoing a total hip replacement, and counselled regarding the complications. Despite these poorer results, however, the patients have improved function and quality of life.

Infection remains a significant and common complication after joint replacement and there is debate about which contributing factors are important. Few studies have investigated the effect of the operating time on infection.

We collected data prospectively from 5277 hip and knee replacements which included the type of procedure, the operating time, the use of drains, the operating theatre, surgeon, age and gender. In a subgroup of 3449 knee replacements further analysis was carried out using the tourniquet time in place of the operating time. These variables were assessed by the use of generalised linear modelling against superficial, deep or joint-space post-operative infection as defined by the Australian Surgical-Site Infection criteria.

The overall infection rate was 0.98%. In the replacement data set both male gender (z = 3.097, p = 0.00195) and prolonged operating time (z = 4.325, p < 0.001) were predictive of infection. In the knee subgroup male gender (z = 2.250, p = 0.02447), a longer tourniquet time (z = 2.867, p = 0.00414) and total knee replacement (versus unicompartmental knee replacement) (z = −2.052, p = 0.0420) were predictive of infection.

These findings support the view that a prolonged operating time and male gender are associated with an increased incidence of infection. Steps to minimise intra-operative delay should be instigated, and care should be exercised when introducing measures which prolong the duration of joint replacement.

Custom-made intercalary endoprostheses may be used for the reconstruction of diaphyseal defects following the resection of bone tumours. The aim of this study was to determine the survival of intercalary endoprostheses with a lap joint design, and to evaluate the clinical results, complications and functional outcome. We retrospectively reviewed six consecutive patients, three of whom underwent limb salvage with intercalary endoprostheses of the tibia, two of the femur, and one of the humerus. Their mean age was 42 years (28 to 64). The mean follow-up was 21.6 months (9 to 58). The humeral prosthesis required revision at 14 months owing to aseptic loosening. There were no implant-related failures. Musculoskeletal Tumour Society functional outcome scores indicated that patients achieved 90% of premorbid function.

Custom intercalary endoprostheses result in reconstructions comparable with, if not better than, those of allografts. Using this design of implant reduces the incidence of early complications and difficulties experienced with previous versions.

Impaction allograft is an established method of securing initial stability of an implant in arthroplasty. Subsequent bone integration can be prolonged, and the volume of allograft may not be maintained. Intermittent administration of parathyroid hormone has an anabolic effect on bone and may therefore improve integration of an implant.

Using a canine implant model we tested the hypothesis that administration of parathyroid hormone may improve osseointegration of implants surrounded by bone graft. In 20 dogs a cylindrical porous-coated titanium alloy implant was inserted into normal cancellous bone in the proximal humerus and surrounded by a circumferential gap of 2.5 mm. Morsellised allograft was impacted around the implant. Half of the animals were given daily injections of human parathyroid hormone (1–34) 5 μg/kg for four weeks and half received control injections. The two groups were compared by mechanical testing and histomorphometry. We observed a significant increase in new bone formation within the bone graft in the parathyroid hormone group. There were no significant differences in the volume of allograft, bone-implant contact or in the mechanical parameters.

These findings suggest that parathyroid hormone improves new bone formation in impacted morsellised allograft around an implant and retains the graft volume without significant resorption. Fixation of the implant was neither improved nor compromised at the final follow-up of four weeks.

The aim of this study was to analyse the functional outcome after a displaced intracapsular fracture of the femoral neck in active patients aged over 70 years without osteoarthritis or rheumatoid arthritis of the hip, randomised to receive either a hemiarthroplasty or a total hip replacement (THR). We studied 252 patients of whom 47 (19%) were men, with a mean age of 81.1 years (70.2 to 95.6). They were randomly allocated to be treated with either a cemented hemiarthroplasty (137 patients) or cemented THR (115 patients). At one- and five-year follow-up no differences were observed in the modified Harris hip score, revision rate of the prosthesis, local and general complications, or mortality. The intra-operative blood loss was lower in the hemiarthroplasty group (7% > 500 ml) than in the THR group (26% > 500 ml) and the duration of surgery was longer in the THR group (28% > 1.5 hours versus 12% > 1.5 hours). There were no dislocations of any bipolar hemiarthroplasty and eight dislocations of a THR during follow-up.

Because of a higher intra-operative blood loss (p < 0.001), an increased duration of the operation (p < 0.001) and a higher number of early and late dislocations (p = 0.002), we do not recommend THR as the treatment of choice in patients aged ≥ 70 years with a fracture of the femoral neck in the absence of advanced radiological osteoarthritis or rheumatoid arthritis of the hip.

We investigated the excess mortality risk associated with fractures of the hip. Data related to 29 134 patients who underwent surgery following a fracture of the hip were obtained from the Scottish Hip Fracture Audit database. Fractures due to primary or metastatic malignancy were excluded. An independent database (General Register Office (Scotland)) was used to validate dates of death. The observed deaths per 100 000 of the population were then calculated for each group (gender, age and fracture type) at various time intervals up to eight years. A second database (Interim Life Tables for Scotland, Scottish Government) was then used to create standardised mortality ratios. Analysis showed that mortality in patients aged > 85 years with a fracture of the hip tended to return to the level of the background population between two and five years after the fracture. In those patients aged < 85 years excess mortality associated with hip fracture persisted beyond eight years. Extracapsular hip fractures and male gender also conferred increased risk.

We present the long-term outcome, at a median of 18 years (12.8 to 23.5) of open posterior bone block stabilisation for recurrent posterior instability of the shoulder in a heterogenous group of 11 patients previously reported on in 2001 at a median follow-up of six years.

We found that five (45%) would not have chosen the operation again, and that four (36%) had further posterior dislocation. Clinical outcome was significantly worse after 18 years than after six years of follow-up (median Rowe score of 60 versus 90 (p = 0.027)). The median Western Ontario Shoulder Index was 60% (37% to 100%) at 18 years’ follow-up, which is a moderate score. At the time of surgery four (36%) had glenohumeral radiological osteoarthritis, which was present in all after 18 years.

This study showed poor long-term results of the posterior bone block procedure for posterior instability and a high rate of glenohumeral osteoarthritis although three patients with post-traumatic instability were pleased with the result of their operations.

The aim of this study was to compare the results in patients having a quadriceps sparing total knee replacement (TKR) with those undergoing a standard TKR at a minimum follow-up of two years.

All patients who had a TKR with a high-flex posterior-stabilised prosthesis prior to December 2002 were reviewed retrospectively. There were 57 patients available for follow-up. Those with a quadriceps sparing TKR had less pain peri-operatively with a greater degree of flexion at all the post-operative visits and at the final follow-up, but their operations took longer, with less accurate radiological alignment. There was no difference in the complications and in the Knee Society scores between the two groups at the final follow-up.

Total knee replacement through a quadriceps sparing approach has some peri-operative advantages over the standard incision. At a minimum follow-up of two years the clinical results were similar to those with a standard incision, but the radiological outcomes of the quadriceps sparing group were inferior.

Open reduction and internal fixation of high-energy pilon fractures are often associated with serious complications. Various methods have been used to treat these injuries, with variable results. A total of 17 consecutive patients with pilon fractures of AO/OTA type 43-B3 (n = 1), type C2 (n = 12) and type C3 (n = 4) were treated by indirect reduction by capsuloligamentotaxis and stabilisation using an ankle-spanning Ilizarov fixator. The calcaneal ring was removed at a mean of 3.7 weeks (3 to 6). A total of 16 patients were available for follow-up at a mean of 29 months (23 to 43). The mean time to healing was 15.8 weeks (13 to 23). Nine patients had pin-track infections but none had deep infection or osteomyelitis. Four patients (25%) had malunion. Fair, good or excellent ankle scores were found in 14 patients. External fixation with a ring fixator achieves stable reduction of the fractured fragments without additional trauma to soft tissues.

With minimum complications and good healing results, the Ilizarov apparatus is particularly useful for high-energy pilon fractures.

We have investigated the effectiveness of the transplantation of bone-marrow-derived mononuclear cells (BMMNCs) with interconnected porous calcium hydroxyapatite (IP-CHA) on early bone repair for osteonecrosis of the femoral head. We studied 22 patients (30 hips) who had osteonecrosis with a minimum follow-up of one year after implantation of BMMNCs. The mean age at surgery was 41 years (18 to 64) and the mean period of follow-up was 29 months (19 to 48). In a control group, cell-free IP-CHA was implanted into a further eight patients (9 hips) with osteonecrosis of the femoral head and the outcomes were compared.

A reduction in the size of the osteonecrotic lesion was observed subsequent to hypertrophy of the bone in the transition zone in the BMMNC group. In three patients in the treatment group progression to extensive collapse was detected. In the control group subtle bone hypertrophy was observed, but severe collapse of the femoral head occurred in six of eight hips.

In this limited study the implantation of BMMNCs and IP-CHA appears to confer benefit in the repair of osteonecrosis and in the prevention of collapse.

Orthopaedic surgery is in an exciting transitional period as modern surgical interventions, implants and scientific developments are providing new therapeutic options. As advances in basic science and technology improve our understanding of the pathology and repair of musculoskeletal tissue, traditional operations may be replaced by newer, less invasive procedures which are more appropriately targeted at the underlying pathophysiology. However, evidence-based practice will remain a basic requirement of care. Orthopaedic surgeons can and should remain at the forefront of the development of novel therapeutic interventions and their application. Progression of the potential of bench research into an improved array of orthopaedic treatments in an effective yet safe manner will require the development of a subgroup of specialists with extended training in research to play an important role in bridging the gap between laboratory science and clinical practice. International regulations regarding the introduction of new biological treatments will place an additional burden on the mechanisms of this translational process, and orthopaedic surgeons who are trained in science, surgery and the regulatory environment will be essential. Training and supporting individuals with these skills requires special consideration and discussion by the orthopaedic community.

In this paper we review some traditional approaches to the integration of orthopaedic science and surgery, the therapeutic potential of current regenerative biomedical science for cartilage repair and ways in which we may develop surgeons with the skills required to translate scientific discovery into effective and properly assessed orthopaedic treatments.

Between 1996 and 2003 six institutions in the United States and France contributed a consecutive series of 234 fractures of the femur in 229 children which were treated by titanium elastic nailing. Minor or major complications occurred in 80 fractures. Full information was available concerning 230 fractures, of which the outcome was excellent in 150 (65%), satisfactory in 57 (25%), and poor in 23 (10%). Poor outcomes were due to leg-length discrepancy in five fractures, unacceptable angulation in 17, and failure of fixation in one. There was a statistically significant relationship (p = 0.003) between age and outcome, and the odds ratio for poor outcome was 3.86 for children aged 11 years and older compared with those below this age. The difference between the weight of children with a poor outcome and those with an excellent or satisfactory outcome was statistically significant (54 kg vs 39 kg; p = 0.003). A poor outcome was five times more likely in children who weighed more than 49 kg.

Delayed rather than early reconstruction of the anterior cruciate ligament is the current recommended treatment for injury to this ligament since it is thought to give a better functional outcome. We randomised 105 consecutive patients with injury associated with chondral lesions no more severe than grades 1 and 2 and/or meniscal tears which only required trimming, to early (< two weeks) or delayed (> four to six weeks) reconstruction of the anterior cruciate ligament using a quadrupled hamstring graft. All operations were performed by a single surgeon and a standard rehabilitation regime was followed in both groups. The outcomes were assessed using the Lysholm score, the Tegner score and measurement of the range of movement. Stability was assessed by clinical tests and measurements taken with the KT-1000 arthrometer, with all testing performed by a blinded uninvolved experienced observer. A total of six patients were lost to follow-up, with 48 patients assigned to the delayed group and 51 to the early group. None was a competitive athlete. The mean interval between injury and the surgery was seven days (2 to 14) in the early group and 32 days (29 to 42) in the delayed group. The mean follow-up was 32 months (26 to 36).

The results did not show a statistically significant difference for the Lysholm score (p = 0.86), Tegner activity score (p = 0.913) or the range of movement (p = 1). Similarly, no distinction could be made for stability testing by clinical examination (p = 0.56) and measurements with the KT-1000 arthrometer (p = 0.93).

Reconstruction of the anterior cruciate ligament gave a similar clinical and functional outcome whether performed early (< two weeks) or late at four to six weeks after injury.

Different calcaneal plates with locked screws were compared in an experimental model of a calcaneal fracture. Four plate models were tested, three with uniaxially-locked screws (Synthes, Newdeal, Darco), and one with polyaxially-locked screws (90° ± 15°) (Rimbus). Synthetic calcanei were osteotomised to create a fracture model and then fixed with the plates and screws. Seven specimens for each plate model were subjected to cyclic loading (preload 20 N, 1000 cycles at 800 N, 0.75 mm/s), and load to failure (0.75 mm/s).

During cyclic loading, the plate with polyaxially-locked screws (Rimbus) showed significantly lower displacement in the primary loading direction than the plates with uniaxially-locked screws (mean values of maximum displacement during cyclic loading: Rimbus, 3.13 mm (sd 0.68); Synthes, 3.46 mm (sd 1.25); Darco, 4.48 mm (sd 3.17); Newdeal, 5.02 mm (sd 3.79); one-way analysis of variance, p < 0.001).

The increased stability of a plate with polyaxially-locked screws demonstrated during cyclic loading compared with plates with uniaxially-locked screws may be beneficial for clinical use.

We have reviewed our experience of the removal of deep extremity orthopaedic implants in children to establish the nature, rate and risk of complications associated with this procedure. A retrospective review was performed of 801 children who had 1223 implants inserted and subsequently removed over a period of 17 years. Bivariate analysis of possible predictors including clinical factors, complications associated with implant insertion and indications for removal and the complications encountered at removal was performed. A logistical regression model was then constructed using those predictors which were significantly associated with surgical complications from the bivariate analyses. Odds ratios estimated in the logistical regression models were converted to risk ratios.

The overall rate of complications after removal of the implant was 12.5% (100 complications in 801 patients), with 48 (6.0%) major and 52 (6.5%) minor. Children with a complication after insertion of the initial implant or with a non-elective indication for removal, a neuromuscular disease associated with a seizure disorder or a neuromuscular disease in those unable to walk, had a significantly greater chance of having a major complication after removal of the implant. Children with all four of these predictors were 14.6 times more likely to have a major complication.

This review describes the development of arthroscopy of the hip over the past 15 years with reference to patient assessment and selection, the technique, the conditions for which it is likely to prove useful, the contraindications and complications related to the procedure and, finally, to discuss possible developments in the future.

Between 1987 and 2006 we performed a modified Thompson’s quadricepsplasty on 40 fracture-related stiff knees and followed the patients for a mean of 7.9 years (2 to 11.1). The factors affecting the final gain of movement were investigated. A total of 15 knees required lengthening of the rectus femoris. The mean flexion gain was 70.2° (42.3° to 112.5°). According to Judet’s criteria, the results were excellent in 30 knees, good in seven, and fair in three. The range of movement which was achieved intra-operatively was related to the gain of knee flexion on univariate analysis. Five patients had complications: deep infection in one, recurrent patellar dislocation in one, and rupture of the extensor mechanism in three. This modified technique gives satisfactory results. Achieving maximum knee flexion intra-operatively seems to be the most important factor in enhancing the outcome in patients with stiffness of the knee following fracture.