We used MRI to study a prospective series of 95 patients with inversion injuries of the ankle and no fracture on plain radiographs. We found an incidence of bone bruises of 27%, but these made no difference to the time of return to work, limitation of walking or physical activity, or the clinical outcome scores at three months. We conclude that bone bruises have very little clinical significance after inversion injuries of the ankle

We have evaluated prospectively the incidence and location of deep-vein thrombosis (DVT), the risk factors for pulmonary embolism, and the natural history of thrombosis after total knee replacement (TKR) in patients who did not receive prophylactic or therapeutic treatment for DVT. We studied 227 patients who underwent primary TKR; 116 had one-stage bilateral and 111 unilateral procedures. Coagulation assays, the full blood count and blood typing tests for the serum chemical profile were undertaken in all patients on three separate occasions. Bilateral simultaneous or unilateral venograms were carried out at six or seven days after operation. Perfusion lung scanning was undertaken before and at seven or eight days after operation. Bilateral simultaneous or unilateral venograms were repeated six months after operation in all patients who had thrombi. In the 116 patients with a bilateral replacement, 97 of 232 venograms (41.8%) were positive for fresh thrombi while there were 46 positive venograms (41.4%) in the 111 patients with a unilateral replacement (p = 1.000). Of the 116 venograms in knees with a cemented replacement, 45 (38.8%) were positive for thrombi while 52 of the 116 venograms (44.8%) were positive in those with a cementless replacement (p = 0.675). Further venograms at six months after operation in all 143 limbs which had thrombi showed that all had completely resolved regardless of the size or location. No pulmonary embolism occurred as shown by negative perfusion lung scans and the absence of symptoms. Although the current prevailing opinion is that patients with thrombosis in the proximal veins should receive anticoagulant treatment, our study has shown that all thrombi regardless of their size or location resolved without causing pulmonary embolism

There are many reports concerning the aetiology and prophylaxis of deep-vein thrombosis (DVT) but little is known about its natural history. The purpose of our study was to identify the incidence and site of DVT, the risk factors for pulmonary embolism and the natural history of DVT after total hip replacement (THR) in patients who do not receive any form of prophylactic or therapeutic treatment for DVT. Two hundred patients who had a primary THR were included: 100 had one-staged bilateral THR and 100 had unilateral THR and 150 implants were cemented and 150 cementless. Coagulation assays, a full blood count, blood typing and serum chemical profile tests were performed for all patients on three separate occasions. Bilateral simultaneous or unilateral venograms were performed on the sixth or seventh postoperative day and perfusion lung scans preoperatively and on the seventh or eighth postoperative day. Further venograms were performed in all patients who had thrombi six months later. In the patients with bilateral THR, 52 (26%) venograms were positive for thrombi, while in the patients with unilateral THR 20 (20%) were positive (p = 0.89). In the patients with a cemented THR, 31 venograms (20.7%) were positive for thrombi, while in those with a cementless THR 41 (27.3%) were positive (p = 0.654). Further venograms in all 72 patients who had thrombi at six months after operation showed that they resolved completely and spontaneously regardless of their site and size. No patients had symptoms of pulmonary emboli and none were seen on the perfusion lung scans. Two patients died from unrelated causes. Although the prevailing opinion is that patients with proximal venous thrombosis should be treated with anticoagulants, our study has shown that all thrombi regardless of their site and size resolve spontaneously without associated pulmonary embolism

In an unselected series of 55 cases of slipped capital femoral epiphysis (SCFE) we observed an incidence of 25% of epiphyseal reduction, mostly unintentional. Reduction indicated physeal instability and was associated with an effusion, detected by sonography on admission, and inability to bear weight. The true prevalence of instability may be higher since an effusion was noted in 33 cases (60%) on the initial sonographic assessment. Serial radiographs showed reduction in 12 (22%), with an average change of 15.1 degrees in the head-neck angle. Serial sonography showed reduction in 7 out of 20 cases (35%), with an average change of 3.7 mm in displacement. In two cases reduction was seen on sonography but not on radiography. Of the hips which showed subsequent reduction, 12 had had a bone scan on admission; three showed initial epiphyseal avascularity but only one progressed to symptomatic avascular necrosis. All stable hips had normal epiphyseal vascularity on the initial bone scan. This indicates the importance of injury from the initial displacement in causing avascular necrosis, rather than effusion, vascular compromise or iatrogenic injury from gentle repositioning. Physeal instability in SCFE is common and should be assessed clinically on admission. It is indicated by joint effusion or inability to bear weight. A slip is very unlikely to be unstable in a child able to bear weight and with no sonographic effusion

Implantation of allograft bone is an integral part of revision surgery of the hip. One major concern with its use is the risk of transmission of infective agents. There are a number of methods of processing allograft bone in order to reduce this risk. One method requires washing the tissue using pulsed irrigation immediately before implantation. We report the incidence of deep bacterial infection in 138 patients (144 revision hip arthroplasties) who had undergone implantation of allograft bone. The bone used was fresh-frozen, non-irradiated and pulse-washed with normal saline before implantation. The deep infection rate at a minimum follow-up of one year was 0.7%. This method of processing appears to be associated with a very low risk of allograft-related bacterial infection

Excessive foot pronation has been considered to be related to anterior knee pain. We undertook a prospective study to test the hypothesis that exertional anterior knee pain is related to the static and dynamic parameters of foot pronation. Two weeks before beginning basic training lasting for 14 weeks, 473 infantry recruits were enrolled into the study and underwent two-dimensional measurement of their subtalar joint displacement angle during walking on a treadmill. Of the 405 soldiers who finished the training 61 (15%) developed exertional anterior knee pain. No consistent association was found between the incidence of anterior knee pain and any of the parameters of foot pronation. While a statistically significant association was found between anterior knee pain and pronation velocity (left foot, p = 0.05; right foot, p = 0.007), the relationship was contradictory for the right and left foot. Our study does not support the hypothesis that anterior knee pain is related to excessive foot pronation

Of 4,617 babies born in Coventry in 1986, a total of 448 (9.7%) had either clinical abnormality of the hip or at risk factors for CDH. All were examined by ultrasound, but only 17 required treatment (3.7 per 1,000); in five of these no clinical abnormality had been detected. An additional 81 babies had ultrasound abnormalities but did not require treatment, despite the fact that ultrasound at first showed major hip displacement in 17 of them. Three late cases of CDH have presented among the babies born in 1986, but not examined by ultrasound. This incidence of late CDH is unchanged compared with the previous nine years, although ultrasound had detected covert displacement in a number of hips

It is important to be able to identify patients with an increased risk of venous thromboembolism (VTE) in order to minimise the risk of an event. We investigated the incidence and risk factors for post-operative VTE in 168 consecutive patients with a malignancy of the lower limb. The period of study included ten months before and 12 months after the introduction of chemical thromboprophylaxis. All data about the potential risk factors were identified and classified into three groups (patient-, surgery- and tumour-related). The outcome measure was a thromboembolic event within 90 days of surgery.

Of the 168 patients, eight (4.8%) had a confirmed symptomatic deep-vein thrombosis and one (0.6%) a fatal pulmonary embolism. Of the 28 variables tested, age > 60 years, higher American Society of Anesthesiologists grade and metastatic tumour were independent risk factors for VTE. The overall rate of symptomatic VTE was not significantly different between patients who received chemical thromboprophylaxis and those who did not. Knowledge of these risk factors may be of value in improving the surgical outcome of patients with a malignancy of the lower limb.

Cite this article: Bone Joint J 2013;95-B:558–62.

Perthes’ disease is an osteonecrosis of the juvenile hip, the aetiology of which is unknown. A number of comorbid associations have been suggested that may offer insights into aetiology, yet the strength and validity of these are unclear. This study explored such associations through a case control study using the United Kingdom General Practice Research database. Associations investigated were those previously suggested within the literature. A total of 619 cases of Perthes’ disease were included, as were 2544 controls. The risk of Perthes’ disease was significantly increased with the presence of congenital anomalies of the genitourinary and inguinal region, such as hypospadias (odds ratio (OR) 4.04 (95% confidence interval (CI) 1.41 to 11.58)), undescended testis (OR 1.83 (95% CI 1.12 to 3.00)) and inguinal herniae (OR 1.79 (95% CI 1.02 to 3.16)). Attention deficit hyperactivity disorder was not associated with Perthes’ disease (OR 1.01 (95% CI 0.48 to 2.12)), although a generalised behavioural disorder was (OR 1.55 (95% CI 1.10 to 2.17)). Asthma significantly increased the risk of Perthes’ disease (OR 1.44 (95% CI 1.17 to 1.76)), which remained after adjusting for oral/parenteral steroid use.

Perthes’ disease has a significant association with congenital genitourinary and inguinal anomalies, suggesting that intra-uterine factors may be critical to causation. Other comorbid associations may offer insight to support or refute theories of pathogenesis.

We report the results of vertebral column resection (VCR) for paediatric patients with spinal deformity. A total of 49 VCRs in paediatric patients from four university hospitals between 2005 and 2009 with a minimum two-year follow-up were retrospectively identified. After excluding single hemivertebral resections (n = 25) and VCRs performed for patients with myelomeningocele (n = 6), as well as spondylectomies performed for tumour (n = 4), there were 14 patients who had undergone full VCR at a mean age of 12.3 years (6.5 to 17.9). The aetiology was congenital scoliosis in five, neuromuscular scoliosis in three, congenital kyphosis in two, global kyphosis in two, adolescent idiopathic scoliosis in one and secondary scoliosis in one. A total of seven anteroposterior and seven posterolateral approaches were used.

The mean major curve deformity was 86° (67° to 120°) pre-operatively and 37° (17° to 80°) at the two-year follow-up; correction was a mean of 54% (18% to 86%) in the anteroposterior and 60% (41% to 70%) in the posterolateral group at the two-year follow-up (p = 0.53). The mean Scoliosis Research Society-24 total scores were 100 (92 to 108) for the anteroposterior and 102 (95 to 105) for the posterolateral group. There was one paraparesis in the anteroposterior group necessitating urgent re-decompression, with a full recovery.

Patients undergoing VCR are highly satisfied after a successful procedure.

Epidemiological studies enhance clinical practice in a number of ways. However, there are many methodological difficulties that need to be addressed in designing a study aimed at the collection and analysis of data concerning fractures and other injuries. Most can be managed and errors minimised if careful attention is given to the design and implementation of the research.

Cite this article: Bone Joint J 2014;96-B:863–7.

Aims

Periprosthetic fracture (PF) after primary total hip arthroplasty (THA) is an uncommon but potentially devastating complication. This study aims to investigate the influence of cemented stem designs on the risk of needing a revision for a PF.

1. An investigation of interdigital clavus or corn does not support the opinion that it is found most often in the web of the fourth interspace.

2. Most occur in that interval, but less than a third involve the web.

3. The commonest site is the area of impingement of the distal interphalangeal joint of the fifth toe on the proximal interphalangeal joint of the fourth.

PCL retaining fixed-bearing TKA is a highly successful operation with the need for more surgery occurring at the rate of approximately 0.4% per year over the first 27 years. The most common cause for revision surgery is related to polyethylene insert failure and accounts for approximately 50% of re-operations. Late metastatic infection is the next most frequent cause followed by patellar problems, late instability and component loosening in decreasing frequency. A myriad of rare miscellaneous problems can also occur.

The Control of Infection Committee at a specialist orthopaedic hospital prospectively collected data on all episodes of bacteriologically-proven deep infection arising after primary hip and knee replacements over a 15-year period from 1987 to 2001.

There were 10 735 patients who underwent primary hip or knee replacement. In 34 of 5947 hip replacements (0.57%) and 41 of 4788 knee replacements (0.86%) a deep infection developed. The most common infecting micro-organism was coagulase-negative staphylococcus, followed by Staphylococcus aureus, enterococci and streptococci. Of the infecting organisms, 72% were sensitive to routine prophylactic antimicrobial agents.

Of the infections, 29% (22) arose in the first three months following surgery, 35% between three months and one year (26), and 36% (27) after one year. Most cases were detected early and treated aggressively, with eradication of the infection in 96% (72). There was no significant change in the infection rate or type of infecting micro-organism over the course of this study.

These results set a benchmark, and importantly emphasise that only 64% of peri-prosthetic infections arise within one year of surgery. These results also illustrate the advantages of conducting joint replacement surgery in the isolation of a specialist hospital.

1. Ten children with scoliosis and cerebral palsy of various types have been reviewed. All underwent operation for correction and stabilisation of the spinal curve, and spinal fusion.

2. Three of the ten patients required supplemental surgery in the form of regrafting, with or without reinsertion of Harrington rods. All have shown considerable correction of the curve, and in all cases the fusion appears to be consolidated. Operation has given these children stable spines which are compensated. Their ability to sit, and in some cases to stand, has improved.

3. In many such cases of scoliosis complicating cerebral palsy Harrington instrumentation and spinal fusion is the only feasible effective form of treatment.

Reports of infection by Clostridium sordellii associated with allograft transplantation have generated considerable interest. We report our experience in recognising clostridial contamination in cadaver donors of musculoskeletal tissue. Tissues obtained from 795 consecutive donors were excised using standard surgical techniques. Samples of blood and bone marrow were also obtained. Donors with clostridia recovered from any site were matched with the preceding donor without clostridia as a procedural and environmental control. The histories of the donors were analysed to determine which variables had a relationship to contamination by running a contingency table and chi-squared test on the variables against the event of a donor being contaminated.

Sixty-four donors (8.1%) had clostridia, most commonly C. sordellii. Clostridia were grown from the blood, marrow and tissue samples of 52, 37 and 30 donors, respectively. In eight cases, they were cultured from the tissue samples alone. There was no significant difference in age or gender between the contaminated donors and the control group. Open wounds were more common in control than in contaminated subjects, but only death by drowning in the contaminated group was statistically significant (p = 0.02). The time between death and the excision of tissue which was contaminated (16 hrs 10 mins) compared with control (11 hrs 10 mins) donors was also significant (p < 10⁻⁶).

We conclude that there is clostridial contamination in a significant number of tissue donors, particularly with increasing time between death and tissue excision. Among the most commonly encountered species is C. sordellii. Multiple microbiological cultures, including blood, are necessary in order to identify clostridial contamination.

A review of 77 neonates who presented with congenital talipes equinovarus over a seven-year period revealed an increase in the condition amongst babies born in the winter quarter. This finding was particularly apparent among the less severe cases of club-foot. Possible reasons for this seasonal variation are discussed.