The lateral compartment is predominantly affected in approximately 10% of patients with osteoarthritis of the knee. The anatomy, kinematics and loading during movement differ considerably between medial and lateral compartments of the knee. This in the main explains the relative protection of the lateral compartment compared with the medial compartment in the development of osteoarthritis. The aetiology of lateral compartment osteoarthritis can be idiopathic, usually affecting the femur, or secondary to trauma commonly affecting the tibia. Surgical management of lateral compartment osteoarthritis can include osteotomy, unicompartmental knee replacement and total knee replacement. This review discusses the biomechanics, pathogenesis and development of lateral compartment osteoarthritis and its management.

Cite this article: Bone Joint J 2013;95-B:436–44.

We report the incidence and location of deep-vein thrombosis in 312 patients who had sustained high-energy, skeletal trauma. They were investigated using magnetic resonance venography and Duplex ultrasound.

Despite thromboprophylaxis, 36 (11.5%) developed venous thromboembolic disease with an incidence of 10% in those with non-pelvic trauma and 12.2% in the group with pelvic trauma. Of patients who developed deep-vein thrombosis, 13 of 27 in the pelvic group (48%) and only one of nine in the non-pelvic group (11%) had a definite pelvic deep-vein thrombosis. When compared with magnetic resonance venography, ultrasound had a false-negative rate of 77% in diagnosing pelvic deep-vein thrombosis. Its value in the pelvis was limited, although it was more accurate than magnetic resonance venography in diagnosing clots in the lower limbs. Additional screening may be needed to detect pelvic deep-vein thrombosis in patients with pelvic or acetabular fractures.

In this retrospective study we evaluated the method of acute shortening and distraction osteogenesis for the treatment of tibial nonunion with bone loss in 17 patients with a mean age of 36 years (10 to 58). The mean bone loss was 5.6 cm (3 to 10). In infected cases, we performed the treatment in two stages. The mean follow-up time was 43.5 months (24 to 96). The mean time in external fixation was 8.0 months (4 to 13) and the mean external fixator index was 1.4 months/cm (1.1 to 1.8). There was no recurrence of infection. The bone evaluation results were excellent in 16 patients and good in one, while functional results were excellent in 15 and good in two. The complication rate was 1.2 per patient.

We conclude that acute shortening and distraction osteogenesis is a safe, reliable and successful method for the treatment of tibial nonunion with bone loss, with a shorter period of treatment and lower rate of complication.

We compared the outcome of closed intramedullary nailing with minimally invasive plate osteosynthesis using a percutaneous locked compression plate in patients with a distal metaphyseal fracture in a prospective study.

A total of 85 patients were randomised to operative stabilisation either by a closed intramedullary nail (44) or by minimally invasive osteosynthesis with a compression plate (41). Pre-operative variables included the patients’ age and the side and pattern of the fracture. Peri-operative variables were the operating time and the radiation time. Postoperative variables were wound problems, the time to union of the fracture, the functional American Orthopaedic Foot and Ankle surgery score and removal of hardware.

We found no significant difference in the pre-operative variables or in the time to union in the two groups. However, the mean radiation time and operating time were significantly longer in the locked compression plate group (3.0 vs 2.12 minutes, p < 0.001, and 97.9 vs 81.2 minutes, p < 0.001, respectively). After one year, all the fractures had united. Patients who had intramedullary nailing had a higher mean pain score, but better function, alignment and total American Orthopaedic Foot and Ankle surgery scores, although the differences were not statistically significant (p = 0.234, p = 0.157, p = 0.897, p = 0.177 respectively). Three (6.8%) patients in the intramedullary nailing group and six (14.6%) in the locked compression plate group showed delayed wound healing, and 37 (84.1%) in the former group and 38 (92.7%) in the latter group expressed a wish to have the implant removed.

We conclude that both closed intramedullary nailing and a percutaneous locked compression plate can be used safely to treat Orthopaedic Trauma Association type-43A distal metaphyseal fractures of the tibia. However, closed intramedullary nailing has the advantage of a shorter operating and radiation time and easier removal of the implant. We therefore prefer closed intramedullary nailing for patients with these fractures.

Medium-term survivorship of the Oxford phase 3 unicompartmental knee replacement (UKR) has not yet been established in an Asian population. We prospectively evaluated the outcome of 400 phase 3 Oxford UKRs in 320 Korean patients with a mean age at the time of operation of 69 years (48 to 82). The mean follow-up was 5.2 years (1 to 10). Clinical and radiological assessment was carried out pre- and post-operatively. At five years, the mean Knee Society knee and functional scores had increased significantly from 56.2 (30 to 91) pre-operatively to 87.2 (59 to 98) (p = 0.034) and from 59.2 (30 to 93) to 88.3 (50 to 100) (p = 0.021), respectively. The Oxford knee score increased from a mean of 25.8 (12 to 39) pre-operatively to 39.8 (25 to 58) at five years (p = 0.038). The ten-year survival rate was 94% (95% confidence interval 90.1 to 98.0). A total of 14 UKRs (3.5%) required revision. The most common reason for revision was dislocation of the bearing in 12 (3%). Conversion to a total knee replacement was required in two patients who developed osteoarthritis of the lateral compartment.

This is the largest published series of UKR in Korean patients. It shows that the mid-term results after a minimally invasive Oxford phase 3 UKR can yield satisfactory clinical and functional results in this group of patients.

Heterotopic ossification (HO) is perhaps the single most significant obstacle to independence, functional mobility, and return to duty for combat-injured veterans of Operation Enduring Freedom and Operation Iraqi Freedom. Recent research into the cause(s) of HO has been driven by a markedly higher prevalence seen in these wounded warriors than encountered in previous wars or following civilian trauma. To that end, research in both civilian and military laboratories continues to shed light onto the complex mechanisms behind HO formation, including systemic and wound specific factors, cell lineage, and neurogenic inflammation. Of particular interest, non-invasive in vivo testing using Raman spectroscopy may become a feasible modality for early detection, and a wound-specific model designed to detect the early gene transcript signatures associated with HO is being tested. Through a combined effort, the goals of early detection, risk stratification, and development of novel systemic and local prophylaxis may soon be attainable.

The treatment of infected exposed implants which have been used for internal fixation usually involves debridement and removal of the implant. This can result in an unstable fracture or spinal column. Muscle flaps may be used to salvage these implants since they provide soft-tissue cover and fresh vascularity. However, there have been few reports concerning their use and these have concentrated on the eradication of the infection and successful soft-tissue cover as the endpoint. There is no information on the factors which may influence the successful salvage of the implant using muscle flaps.

We studied the results and factors affecting outcome in nine pedicled muscle flaps used in the treatment of exposed metal internal fixation with salvage of the implant as the primary endpoint. This was achieved in four cases. Factors predicting success were age < 30 years, the absence of comorbid conditions and a favourable microbiological profile. The growth of multiple organisms, a history of smoking and the presence of methicillin-resistant Staphylococcus aureus on wound cultures indicated a poor outcome. The use of antibiotic beads, vacuum-assisted closure and dressing, the surgical site, the type of flap performed and the time from primary surgery to flap cover were not predictive of outcome.

Non-accidental injury (NAI) in children includes orthopaedic trauma throughout the skeleton. Fractures with soft-tissue injuries constitute the majority of manifestations of physical abuse in children. Fracture and injury patterns vary with age and development, and NAI is intrinsically related to the mobility of the child. No fracture in isolation is pathognomonic of NAI, but specific abuse-related injuries include multiple fractures, particularly at various stages of healing, metaphyseal corner and bucket-handle fractures and fractures of ribs. Isolated or multiple rib fractures, irrespective of location, have the highest specificity for NAI. Other fractures with a high specificity for abuse include those of the scapula, lateral end of the clavicle, vertebrae and complex skull fractures.

Injuries caused by NAI constitute a relatively small proportion of childhood fractures. They may be associated with significant physical and psychological morbidity, with wide- ranging effects from deviations in normal developmental progression to death.

Orthopaedic surgeons must systematically assess, recognise and act on the indicators for NAI in conjunction with the paediatric multidisciplinary team.

We assessed the reliability, accuracy and variability of closed-wedge high tibial osteotomy (HTO) using computer-assisted surgery compared to the conventional technique. A total of 50 closed-wedge HTO procedures were performed using the navigation system, and compared with 50 HTOs that had been performed with the conventional technique. In the navigation group, the mean mechanical axis prior to osteotomy was varus 8.2°, and the mean mechanical axis following fixation was valgus 3.6°. On the radiographs the mean pre-operative mechanical axis was varus 7.3°, and the mean post-operative mechanical axis was valgus 2.1°. There was a positive correlation between the measured data taken under navigation and by radiographs (r > 0.3, p < 0.05). The mean correction angle was significantly more accurate in the navigation group (p < 0.002). The variability of the correction was significantly lower in the navigation group (2.3° vs 3.7°, p = 0,012). We conclude that navigation provides reliable real-time intra-operative information, may increase accuracy, and improves the precision of a closed-wedge HTO.

We present the prevalence of multiple fractures in the elderly in a single catchment population of 780 000 treated over a 12-month period and describe the mechanisms of injury, common patterns of occurrence, management, and the associated mortality rate. A total of 2335 patients, aged ≥ 65 years of age, were prospectively assessed and of these 119 patients (5.1%) presented with multiple fractures. Distal radial (odds ratio (OR) 5.1, p <  0.0001), proximal humeral (OR 2.2, p < 0.0001) and pelvic (OR 4.9, p < 0.0001) fractures were associated with an increased risk of sustaining associated fractures. Only 4.5% of patients sustained multiple fractures after a simple fall, but due to the frequency of falls in the elderly this mechanism resulted in 80.7% of all multiple fractures. Most patients required admission (> 80%), of whom 42% did not need an operation but more than half needed an increased level of care before discharge (54%). The standardised mortality rate at one year was significantly greater after sustaining multiple fractures that included fractures of the pelvis, proximal humerus or proximal femur (p < 0.001). This mortality risk increased further if patients were < 80 years of age, indicating that the existence of multiple fractures after low-energy trauma is a marker of mortality.

The operative treatment of displaced fractures of the tibial plateau is challenging. Recent developments in the techniques of internal fixation, including the development of locked plating and minimal invasive techniques have changed the treatment of these fractures. We review current surgical approaches and techniques, improved devices for internal fixation and the clinical outcome after utilisation of new methods for locked plating.

The treatment of developmental dysplasia of the hip diagnosed after the first year of life remains controversial. A series of 36 children (47 hips), aged between one and 4.9 years underwent gradual closed reduction using the Petit-Morel method. A pelvic osteotomy was required in 43 hips (91.5%). The patients whose hips did not require pelvic osteotomy were among the youngest. The mean age at final follow-up was 16.1 years (11.3 to 32). The mean follow-up was 14.3 years (10 to 30).

At the latest follow-up, 44 hips (93.6%) were graded as excellent or good according to the Severin classification. Closed reduction failed in only two hips (4.3%) which then required open reduction. Mild avascular necrosis was observed in one (2.1%).

The accuracy of the reduction and associated low complication rate justify the use of the Petit-Morel technique as the treatment of choice for developmental dysplasia of the hip in patients aged between one and five years.

The Canadian Orthopaedic Trauma Society was started in an endeavour to answer the difficult problem of obtaining enough patients to perform top-quality research into fractures. By maintaining a high standard, including randomised study design, inclusivity, open discussion among surgeons and excellent long-term follow-up, this group has become a leader in the orthopaedic research community. This annotation describes the short history, important components and spirit necessary to build a research community or team which will function well despite the difficult research environment facing individual surgeons.

Stable fractures of the ankle can be successfully treated non-operatively by a below-knee plaster cast. In some centres, patients with this injury are routinely administered low-molecular-weight heparin, to reduce the risk of deep-vein thrombosis (DVT). We have assessed the incidence of DVT in 100 patients in the absence of any thromboprophylaxis. A colour Doppler duplex ultrasound scan was done at the time of the removal of the cast.

Five patients did develop DVT, though none had clinical signs suggestive of it. One case involved the femoral and another the popliteal vein. No patient developed pulmonary embolism. As the incidence of DVT after ankle fractures is low, we do not recommend routine thromboprophylaxis.