The application and interpretation of the impact factor of a journal is fraught with problems, some of which are explored in this editorial.

Thromboprophylaxis remains a controversial subject. A vast amount of epidemiological and trial data about venous thromboembolism has been published over the past 40 years. These data have been distilled and synthesised into guidelines designed to help the practitioner translate this extensive research into ‘evidence-based’ advice.

Guidelines should, in theory, benefit patient care by ensuring that every patient routinely receives the best prophylaxis; without guidelines, it is argued, patients may fail to receive treatment or be exposed to protocols which are ineffective, dangerous or expensive.

Guidelines, however, have not been welcomed or applied universally. In the United States, orthopaedic surgeons have published their concerns about the thromboprophylaxis guidelines prepared by the American College of Chest Physicians. In Britain, controversy persists with many surgeons unconvinced of the risk/benefit, cost/benefit or practicality of thromboprophylaxis. The extended remit of the recent National Institute of Clinical Excellence thromboprophylaxis guidelines has been challenged.

The reasons for this disquiet are addressed in this paper and particular emphasis is placed on how clinically-acceptable guidelines could be developed and applied.

Kienböck’s disease is a form of osteonecrosis affecting the lunate. Its aetiology remains unknown. Morphological variations, such as negative ulnar variance, high uncovering of the lunate, abnormal radial inclination and/or a trapezoidal shape of the lunate and the particular pattern of its vascularity may be predisposing factors. A history of trauma is common. The diagnosis is made on plain radiographs, but MRI can be helpful early in the disease. A CT scan is useful to demonstrate fracture or fragmentation of the lunate. Lichtman classified Kienböck disease into five stages. The natural history of the condition is not well known, and the symptoms do not correlate well with the changes in shape of the lunate and the degree of carpal collapse. There is no strong evidence to support any particular form of treatment. Many patients are improved by temporary immobilisation of the wrist, which does not stop the progression of carpal collapse. Radial shortening may be the treatment of choice in young symptomatic patients presenting with stages I to III-A of Kienböck’s disease and negative ulnar variance. Many other forms of surgical treatment have been described.

We evaluated triple-phase bone scintigraphy in the differential diagnosis of peri-prosthetic infection in 46 patients with a total hip replacement or bipolar hemiarthroplasty who were due for revision surgery. There were 18 men and 28 women, with a mean age at operation of 64.6 years (28 to 81). We defined peri-prosthetic infection as an increased uptake of radioisotope in all the phases of triple-phase bone scintigraphy and validated these results against the histological and/or microbiology results in every case.

The positive and negative predictive values for the presence of infection were 83% and 93%, respectively. The diagnostic sensitivity was 88% and the specificity was 90%.

This study indicates that triple-phase bone scintigraphy is a useful tool in the detection of peri-prosthetic infection and offers a cost-effective method of screening.

We present a series of 114 patients with microbiologically-proven chronically-infected total hip replacement, treated between 1991 and 2004 by a two-stage exchange procedure with antibiotic-loaded cement, but without the use of a prolonged course of antibiotic therapy. The mean follow-up for all patients was 74 months (2 to 175) with all surviving patients having a minimum follow-up of two years. Infection was successfully eradicated in 100 patients (87.7%), a rate which is similar to that reported by others, but where prolonged adjuvant antibiotic therapy has been used. Using the technique described, a prolonged course of systemic antibiotics does not appear to be essential and the high cost of the administration of antibiotics can be avoided.

Ultra-high-molecular-weight polyethylene sterilised in the absence of air and highly cross-linked polyethylene have been used to avoid osteolysis and loosening in total hip replacement. Our prospective randomised study has assessed the results using two different polyethylenes associated with the same prosthetic design. We assessed 45 Allofit acetabular components with a Sulene-polyethylene liner of conventional polyethylene gamma sterilised with nitrogen and 45 Allofit acetabular components with a Durasul-polyethylene liner sterilised in ethylene oxide, both matched with an Alloclassic stem with a 28 mm modular femoral head. The prostheses were implanted between May 1999 and December 2001. The mean follow-up was for 66.3 months (60 to 92). The linear penetration of the femoral head was estimated at 6 weeks, at 6 and 12 months and annually thereafter from standardised digitised radiographs using image-analysis software.

There was no loosening of any prosthetic component. There were no radiolucent lines or osteolysis. The mean rate of penetration calculated from regression analysis during the first five years was 38 μm/year (sd 2) for the Sulene group and 6 μm/year (sd 1) for the Durasul group (p = 0.00002). The rate of penetration of the Durasul group was 15.7% of that of the Sulene group.

Total hip replacement in patients with advanced osteonecrosis of the femoral head is often complicated by early loosening of the femoral component. Recent evidence has suggested that abnormal bone extending into the proximal femur may be responsible for the early failure of the femoral component. We aimed to identify which patients were at high risk of early failure by evaluating gadolinium-enhanced MR images of histologically-confirmed osteonecrotic lesions beyond the femoral head.

Although the MR signal intensity has been shown to correlate well with osteonecrosis in the femoral head, it was found to be relatively insensitive at identifying lesions below the head, with a sensitivity of only 51% and a predictive value of a negative result of only 48%. However, the specificity was 90%, with the predictive value of a positive MRI finding being 86%. Only those patients with osteonecrosis of the femoral head secondary to sickle-cell disease, who are known to be at high risk of early loosening, had changes in the MR signal in the greater trochanter and the femoral shaft. This observation suggests that changes in the MR signal beyond the femoral head may represent osteonecrotic lesions in areas essential for the fixation of the femoral component. Pre-operative identification of such lesions in the neck of the femur may be important when considering hip resurfacing for osteonecrosis of the femoral head, following which early loosening of the femoral component and fracture of the neck are possible complications.

We studied the influence of soft-tissue releases and soft-tissue balance on the outcome of 526 total knee replacements one year after operation. The surgery had been performed by seven surgeons in five centres in the United Kingdom between October 1999 and December 2002. Balancing was carried out by five surgeons using spacers and trials and by two surgeons using a ‘balancer’ instrument. All the surgeons assessed the adequacy of their releases by taking measurements with the balancer after soft-tissue release before implanting the components. Independent observers collected the Oxford knee scores and applied the American Knee Society functional and knee scores as well as recording the range of movement of the replaced knee. These were compared with the pre-operative scores and the extent of the releases.

We found differences in outcomes between minimal and extensive releases and between balanced and imbalanced knees.

Knees requiring extensive soft-tissue releases showed greater change in the short-term clinical outcome without increased complications and achieved similar results at one year compared with those with less deformity pre-operatively which had required less soft-tissue release. Balancing an imbalanced knee improved the short-term knee outcome.

We suggest that different mechanisms underlie joint pain at rest and on movement in osteoarthritis and that separate assessment of these two features with a visual analogue scale (VAS) offers better information about the likely effect of a total knee replacement (TKR) on pain. The risk of persistent pain after TKR may relate to the degree of central sensitisation before surgery, which might be assessed by determining the pain threshold to an electrical stimulus created by a special tool, the Pain Matcher. Assessments were performed in 69 patients scheduled for TKR. At 18 months after operation, separate assessment of pain at rest and with movement was again carried out using a VAS in order to enable comparison of pre- and post-operative measurements. A less favourable outcome in terms of pain relief was observed for patients with a high pre-operative VAS score for pain at rest and a low pain threshold, both features which may reflect a central sensitisation mechanism.

There is little evidence examining the relationship between anatomical landmarks, radiological placement of the tunnels and long-term clinical outcomes following anterior cruciate ligament (ACL) reconstruction. The aim of this study was to investigate the reproducibility of intra-operative landmarks for placement of the tunnels in single-bundle reconstruction of the ACL using four-strand hamstring tendon autografts.

Isolated reconstruction of the ACL was performed in 200 patients, who were followed prospectively for seven years with use of the International Knee Documentation Committee forms and radiographs. Taking 0% as the anterior and 100% as the posterior extent, the femoral tunnel was a mean of 86% (sd 5) along Blumensaat’s line and the tibial tunnel was 48% (sd 5) along the tibial plateau. Taking 0% as the medial and 100% as the lateral extent, the tibial tunnel was 46% (sd 3) across the tibial plateau and the mean inclination of the graft in the coronal plane was 19° (sd 5.5).

The use of intra-operative landmarks resulted in reproducible placement of the tunnels and an excellent clinical outcome seven years after operation. Vertical inclination was associated with increased rotational instability and degenerative radiological changes, while rupture of the graft was associated with posterior placement of the tibial tunnel. If the osseous tunnels are correctly placed, single-bundle reconstruction of the ACL adequately controls both anteroposterior and rotational instability.

Trochlear dysplasia is a developmental condition characterised by an abnormally flat or dome-shaped trochlea and is an important contributory factor to patellofemoral instability and recurrent dislocation. We studied prospectively a series of 54 consecutive patients (59 knees) with patellofemoral instability secondary to trochlear dysplasia, who were treated by a trochleoplasty by a single surgeon between June 2002 and June 2007.

Pre- and post-operative scores were assessed by the patients and a satisfaction questionnaire was completed.

Of the 54 patients (59 knees) in the series, 39 (44 knees) were female and 15 (15 knees) were male. Their mean age at surgery was 21 years and 6 months (14 years 4 months to 33 years 11 months). In 40 patients (42 knees) the mean follow-up was for 24 months (12 to 58). One patient was unable to attend for follow-up. An analysis of the results of those patients followed up for at least 12 months showed a statistically significant improvement in outcome (p < 0.001 for all scores). Overall, 50 patients (92.6%) were satisfied with the outcome of their procedure.

The early results of trochleoplasty are encouraging in this challenging group of patients.

Chronic infections and ulceration around the tendo Achillis are difficult to manage. Split-skin grafts do not survive even on healthy exposed tendon. Refractory cases may require plastic surgical intervention with the use of free flaps. Patients with significant vascular disease are not suitable for such techniques. Flexor hallucis longus tendon transfer is an established treatment for chronic ruptures of the tendo Achillis.

We report the successful treatment of an infected tendo Achillis with excision and reconstruction with flexor hallucis longus transfer. The muscle belly of this tendon allowed later skin grafting while the tendon transfer provided good functional recovery.

We reviewed the outcome of arthroscopic stabilisation of anterior glenohumeral instability in young adults using the transglenoid suture technique. A questionnaire was sent to 455 consecutive patients who had undergone this procedure between 1992 and 2000. Of these, 312 patients (68.5%) with 313 affected shoulders and a mean age of 20 years (18 to 28) responded.

Outcome was determined by the number of re-dislocations or, in patients who had not re-dislocated, by the disease-specific quality of life as measured by the Western Ontario Shoulder Instability index. During a mean follow-up of 6.4 years (1 to 14), 177 patients (56%) sustained a re-dislocation, including 70 who required a further operation. In 136 patients (44%) who reported neither re-dislocation nor re-operation, the index scores were good (median 90.4%; 28.9% to 100%). No significant peri- or pre-operative predictors of re-dislocation or re-operation were found.

We found a high rate of re-dislocation after transglenoid suture repair in young, physically active patients.

The results of proximal humeral replacement following trauma are substantially worse than for osteoarthritis or rheumatoid arthritis. The stable reattachment of the lesser and greater tuberosity fragments to the rotator cuff and the restoration of shoulder biomechanics are difficult. In 1992 we developed a prosthesis designed to improve fixation of the tuberosity fragments in comminuted fractures of the proximal humerus. The implant enables fixation of the fragments to the shaft of the prosthesis and the diaphyseal fragment using screws, washers and a special toothed plate. Between 1992 and 2003 we used this technique in 50 of 76 patients referred to our institution for shoulder reconstruction after trauma. In the remaining 26, reconstruction with a prosthesis and nonabsorbable sutures was performed, as the tuberosity fragments were too small and too severely damaged to allow the use of screws and the toothed plate.

The Constant score two years post-operatively was a mean of 12 points better in the acute trauma group and 11 points better in the late post-traumatic group than in the classical suture group.

We recommend this technique in patients where the tuberosity fragments are large enough to allow fixation with screws, washers and a toothed plate.

We describe a method for stabilising the distal radioulnar joint using a double breasted slip of extensor retinaculum.

This is a retrospective series of 30 patients with a painful wrist secondary to instability of the distal radioulnar joint. The results were assessed by a modified Mayo Score. The mean follow-up was for 38.1 months (13 months to 8 years).

Twelve patients had excellent, 16 good and 2 fair outcomes. One patient had experienced temporary numbness in the distribution of the dorsal branch of the ulnar nerve. The modified Mayo wrist score increased from a pre-operative mean of 23.89 (10 to 50) to a final mean of 94.4 (85 to 100).

Stabilisation of the distal radioulnar joint by the method of using a double breasted slip of the extensor retinaculum gives satisfactory results. The procedure is simple and reproducible.

We investigated whether our policy of routine re-excision of the tumour bed after an unplanned excision of a soft-tissue sarcoma was justified.

Between April 1982 and December 2005, 2201 patients were referred to our hospital with the diagnosis of soft-tissue sarcoma, of whom 402 (18%) had undergone an unplanned excision elsewhere. A total of 363 (16.5%) were included in this study. Each patient was routinely restaged and the original histology was reviewed. Re-excision was undertaken in 316 (87%). We analysed the patient, tumour and treatment factors in relation to local control, metastasis and overall survival.

Residual tumour was found in 188 patients (59%). There was thus no residual disease in 128 patients of whom 10% (13) went on to develop a local recurrence. In 149 patients (47%), the re-excision specimen contained residual tumour, but it had been widely excised. Local recurrence occurred in 30 of these patients (20%). In 39 patients (12%), residual tumour was present in a marginal resection specimen. Of these, 46% (18) developed a local recurrence. A final positive margin in a high-grade tumour had a 60% risk of local recurrence even with post-operative radiotherapy.

Metastases developed in 24% (86). The overall survival was 77% at five years. Survival was related to the grade of the tumour and the finding of residual tumour at the time of re-excision.

We concluded that our policy of routine re-excision after unplanned excision of soft-tissue sarcoma was justified in view of the high risk of finding residual tumour.

We have investigated the oncological outcome of 63 patients with soft-tissue sarcomas of the hand managed at three major centres in the United Kingdom. There were 44 males and 19 females with a mean age of 45 years (11 to 92). The three most common diagnoses were synovial sarcoma, clear cell sarcoma and epithelioid sarcoma. Local excision was carried out in 45 patients (71%) and amputation in 18 (29%). All those treated by amputation had a wide margin of excision but this was only achieved in 58% of those treated by local excision. The risk of local recurrence was 6% in those treated by amputation compared with 42% for those who underwent attempted limb salvage. An inadequate margin of excision resulted in a 12 times greater risk of local recurrence when compared with those in whom a wide margin of excision had been achieved. We were unable to demonstrate any role for radiotherapy in decreasing the risk of local recurrence when there was an inadequate margin of excision. Patients with an inadequate margin of excision had a much higher risk of both local recurrence and metastasis than those with wide margins. The overall survival rate at five years was 87% and was related to the grade and size of the tumour and to the surgical margin.

We have shown that a clear margin of excision is essential to achieve local control of a soft-tissue sarcoma in the hand and that failure to achieve this results in a high risk of both local recurrence and metastastic disease.

Compartment pressures have not previously been studied in healthy children. We compared the pressures in the four lower leg compartments of healthy children with those of healthy adults.

We included patients aged between two months and six years, and measured the pressures in 80 compartments of 20 healthy children using simple needle manometry. Measurements were repeated in a control group of 20 healthy adults.

The mean compartment pressure in the lower leg in children was significantly higher than in adults (p < 0.001). On average, pressures in the four compartments varied between 13.3 mmHg and 16.6 mmHg in the children and between 5.2 mmHg and 9.7 mmHg in the adults. The latter is in accordance with those recorded in the literature. The mean arterial pressure did not relate to age or to pressure in the compartment.

The findings of this study that the normal compartment pressure of the lower leg in healthy children is significantly higher than that in adults may be of considerable significance in clinical decision-making in children of this age.

A total of 38 patients with leprosy and localised nerve damage (11 median at the wrist and 37 posterior tibial at the ankle) were treated by 48 freeze-thawed skeletal muscle autografts ranging between 2.5 cm and 14 cm in length. Sensory recovery was noted in 34 patients (89%) and was maintained during a mean period of follow-up of 12.6 years (4 to 14). After grafting the median nerve all patients remained free of ulcers and blisters, ten demonstrated perception of texture and eight recognised weighted pins. In the posterior tibial nerve group, 24 of 30 repairs (80%) resulted in improved healing of the ulcers and 26 (87%) demonstrated discrimination of texture. Quality of life and hand and foot questionnaires showed improvement; the activities of daily living scores improved in six of seven after operations on the hand, and in 14 of 22 after procedures on the foot. Another benefit was subjective improvement in the opposite limb, probably because of the protective effect of better function in the operated side. This study demonstrates that nerve/muscle interposition grafting in leprosy results in consistent sensory recovery and high levels of patient satisfaction. Ten of 11 patients with hand operations and 22 of 25 with procedures to the foot showed sensory recovery in at least one modality.

An 86-year-old male presented with a loose total hip replacement (THR) ten years after implantation. At revision for anticipated aseptic loosening, watery pus was found in the joint and Bacille-Calmette-Guérin (BCG) was seen on culture. The bacterial strain was identified and was identical to the BCG used in the intravesicular treatment of superficial bladder carcinoma in this patient ten months earlier. After revision he received a full course of antituberculous treatment.

The clinical and radiological results were excellent after follow-up for 30 months with his uncemented THR showing satisfactory incorporation. His inflammatory markers were normal and his Harris hip score was 95 points.

The diagnosis of a tuberculous infection can be easily missed, but must be considered, especially if sterile pus is encountered.

Metal meshes are used in revision surgery of the hip to contain impacted bone grafts in cases with cortical or calcar defects in order to provide rotational stability to the stem. However, the viability of bone allografts under these metal meshes has been uncertain.

We describe the histological appearances of biopsies obtained from impacted bone allografts to the calcar contained by a metal mesh in two femoral reconstructions which needed further surgery at 24 and 33 months after the revision procedure.

A line of osteoid and viable new bone was observed on the surface of necrotic trabeculae. Active bone marrow between these trabeculae showed necrotic areas in some medullary spaces with reparative fibrous tissue and isolated reactive lymphocytes. This is interpreted as reparative changes after revascularisation of the cancellous allografts.

These pathological findings are similar to those reported in allografts contained by cortical host bone and support the hypothesis that incorporation of morcellised bone under metal meshes is not affected by these devices.

We describe two cases of osteochondritis dissecans (OCD) affecting both femoral condyles in the same knee. The patients presented with recurrent episodes of pain and swelling, but these were initially thought to be ‘growing pains’. Eventually, a delayed diagnosis of bicondylar OCD was established and both patients were referred for further management. After assessing the extent of the disease on MRI, matrix-induced autologous chondrocyte implantation was performed to treat the defects of the lateral condyle in each case, with a plan to address the medial defects at a later stage. Proposed theories on the aetiology of the condition and available methods of treatment are discussed. A diagnosis of OCD should be considered in young patients with persistent knee pain and effusions, and MRI is the investigation of choice for early detection.

Giant-cell tumour of the synovium is known to affect the fingers or toes of adults. It has seldom been described in the spine and rarely in the thoracic vertebrae or in a child. The lesions of giant-cell tumour of the synovium have a classical radiological appearance, but require a high index of suspicion for correct recognition. Unlike giant-cell tumour of the synovium at other well-known sites, spinal lesions lack the characteristic papillary architecture, thereby raising other diagnostic possibilities. We describe a giant-cell tumour of the synovium of the left facet joint of a thoracic vertebra in a nine-year-old girl. The tumour was treated successfully by surgical excision.

A 48-year old man presented with back pain that was resistant to treatment. An MR scan showed spondylolisthesis at L4-5 and narrowing of the exit foraminae. He had a posterior fusion which did not relieve his symptoms. He continued to have back pain and developed subcutaneous nodules in both forearms. Biopsy from the skin revealed cutaneous sarcoidosis, and one from the lumbar spine showed sarcoidosis granuloma between the bone trabeculae. A CT scan of the abdomen and chest revealed axillary lymphadenopathy, mediastinal enlarged nodes, apical nodular nodes and splenomegaly. The patient was started on large doses of methotrexate and steroids. His angiotensin-converting enzyme and calcium levels returned to normal and the back pain resolved.

A 64-year-old man presented with a severe deformity of the tibia caused by Paget’s disease and osteoarthritis of the ipsilateral knee. Total knee replacement required preliminary correction of the tibial deformity. This was successfully achieved by tibial osteotomy followed by distraction osteogenesis using the Taylor spatial frame. The subsequent knee replacement was successful, with no recurrence of deformity.

An experimental sheep model was used for impaction allografting of 12 hemiarthroplasty femoral components placed into two equal-sized groups. In group 1, a 50:50 mixture of ApaPore hydroxyapatite bone-graft substitute and allograft was used. In group 2, ApaPore and allograft were mixed in a 90:10 ratio. Both groups were killed at six months. Ground reaction force results demonstrated no significant differences (p > 0.05) between the two groups at 8, 16 and 24 weeks post-operatively, and all animals remained active. The mean bone turnover rates were significantly greater in group 1, at 0.00206 mm/day, compared to group 2 at 0.0013 mm/day (p < 0.05). The results for the area of new bone formation demonstrated no significant differences (p > 0.05) between the two groups. No significant differences were found between the two groups in thickness of the cement mantle (p > 0.05) and percentage ApaPore-bone contact (p > 0.05).

The results of this animal study demonstrated that a mixture of ApaPore allograft in a 90:10 ratio was comparable to using a 50:50 mixture.

Using a rat model the characteristics of the sensory neurones of the dorsal-root ganglia (DRG) innervating the hip were investigated by retrograde neurotransport and immunohistochemistry.

Fluoro-Gold solution (FG) was injected into the left hip of ten rats. Seven days later the DRG from both sides between T12 and L6 were harvested. The number of FG-labelled calcitonin gene-related peptide-immunoreactive or isolectin B4-binding neurones were counted.

The FG-labelled neurones were distributed throughout the left DRGs between T13 and L5, primarily at L2, L3, and L4. Few FG-labelled isolectin B4-binding neurones were present in the DRGs of either side between T13 and L5, but calcitonin gene-related peptide-immunoreactive neurones made up 30% of all FG-labelled neurones.

Our findings may explain the referral of pain from the hip to the thigh or lower leg corresponding to the L2, L3 and L4 levels. Since most neurones are calcitonin gene-related peptide-immunoreactive peptide-containing neurones, they may have a more significant role in the perception of pain in the hip as peptidergic DRG neurones.

We have evaluated in vitro the accuracy of percutaneous and ultrasound registration as measured in terms of errors in rotation and version relative to the bony anterior pelvic plane in computer-assisted total hip replacement, and analysed the intra- and inter-observer reliability of manual or ultrasound registration.

Four clinicians were asked to perform registration of the landmarks of the anterior pelvic plane on two cadavers. Registration was performed under four different conditions of acquisition. Errors in rotation were not significant. Version errors were significant with percutaneous methods (16.2°; p < 0.001 and 19.25° with surgical draping; p < 0.001), but not with the ultrasound acquisition (6.2°, p = 0.13). Intra-observer repeatability was achieved for all the methods. Inter-observer analysis showed acceptable agreement in the sagittal but not in the frontal plane.

Ultrasound acquisition of the anterior pelvic plane was more reliable in vitro than the cutaneous digitisation currently used.