Following the recall of modular neck hip stems in July 2012, research into femoral modularity will intensify over the next few years. This review aims to provide surgeons with an up-to-date summary of the clinically relevant evidence. The development of femoral modularity, and a classification system, is described. The theoretical rationale for modularity is summarised and the clinical outcomes are explored. The review also examines the clinically relevant problems reported following the use of femoral stems with a modular neck.

Joint replacement registries in the United Kingdom and Australia have provided data on the failure rates of modular devices but cannot identify the mechanism of failure. This information is needed to determine whether modular neck femoral stems will be used in the future, and how we should monitor patients who already have them implanted.

Cite this article: Bone Joint J 2013;95-B:1011–21.

A review of the current literature shows that there is a lack of consensus regarding the treatment of spondylolysis and spondylolisthesis in children and adolescents. Most of the views and recommendations provided in various reports are weakly supported by evidence. There is a limited amount of information about the natural history of the condition, making it difficult to compare the effectiveness of various conservative and operative treatments. This systematic review summarises the current knowledge on spondylolysis and spondylolisthesis and attempts to present a rational approach to the evaluation and management of this condition in children and adolescents.

The outcome of one-stage bilateral open reduction through a medial approach for the treatment of developmental dysplasia of the hip in children under 18 months was studied in 23 children, 18 girls and five boys. Their mean age at operation was 10.1 months (6 to 17) and the mean follow-up was 5.4 years (3 to 8).

Acceptable clinical and radiological results were achieved in 44 (95.7%) and 43 (93.5%) of 46 hips, respectively. Excellent results were significantly evident in patients younger than 12 months, those who did not require acetabuloplasty, those whose ossific nucleus had appeared, and in those who did not develop avascular necrosis.

One-stage bilateral medial open reduction avoids the need for separate procedures on the hips and has the advantages of accelerated management and shorter immobilisation and rehabilitation than staged operations.

We report a case of osteonecrosis of the femoral head in a young man who is a carrier of the prothrombin gene mutation. We suggest that an electrical injury to his lower limb may have triggered intravascular thrombosis as a result of this mutation with subsequent osteonecrosis of the femoral head. No case of osteonecrosis of the femoral head secondary to a distant electrical injury has previously been reported.

The December 2012 Spine Roundup³⁶⁰ looks at: the Japanese neck disability index; adjacent segment degeneration; sacroiliac loads determined by limb length discrepancy; whether epidural steroids improve outcome in lumbar disc herniation; spondylodiscitis in infancy; total pedicle screws; and iliac crest autograft complications.

Using the General Practice Research Database, we examined the temporal changes in the rates of primary total hip (THR) and total knee (TKR) replacement, the age at operation and the female-to-male ratio between 1991 and 2006 in the United Kingdom.

We identified 27 113 patients with THR and 23 843 with TKR. The rate of performance of THR and TKR had increased significantly (p < 0.0001 for both) during the 16-year period and was greater for TKR, especially in the last five years. The mean age at operation was greater for women than for men and had remained stable throughout the period of study. The female-to-male ratio was higher for THR and TKR and had remained stable.

The data support the notion that the rate of joint replacement is increasing in the United Kingdom with the rate of TKR rising at the highest rate. The perception that the mean age for TKR has decreased over time is not supported.

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 reviewed the results of 84 total hip replacements performed with a short metaphyseal-fitting anatomical cementless femoral component in 84 unselected consecutive patients with a mean age of 78.9 years (70 to 88). The mean follow-up was 4.6 years (4 to 5). The mean pre-operative Harris hip score was 26 points (0 to 56), which improved to 89 (61 to 100) at the final follow-up. No patient had thigh pain. The mean pre-operative Western Ontario and McMaster Universities osteoarthritis index score was 61 points (48 to 75), which improved to 21 (6 to 46). The mean University of California, Los Angeles activity score was 5.5 points (3 to 7) at the final follow-up. Osseointegration was seen in all femoral and acetabular components. All hips had grade 1 stress shielding of the proximal femur. No acetabular or femoral osteolysis was identified.

These results demonstrate that a short metaphyseal-fitting femoral component achieves optimal fixation without diaphyseal anchorage in elderly patients.

Neurogenic heterotopic ossification (NHO) is a disorder of aberrant bone formation affecting one in five patients sustaining a spinal cord injury or traumatic brain injury. Ectopic bone forms around joints in characteristic patterns, causing pain and limiting movement especially around the hip and elbow. Clinical sequelae of neurogenic heterotopic ossification include urinary tract infection, pressure injuries, pneumonia and poor hygiene, making early diagnosis and treatment clinically compelling. However, diagnosis remains difficult with more investigation needed. Our pathophysiological understanding stems from mechanisms of basic bone formation enhanced by evidence of systemic influences from circulating humor factors and perhaps neurological ones. This increasing understanding guides our implementation of current prophylaxis and treatment including the use of non-steroidal anti-inflammatory drugs, bisphosphonates, radiation therapy and surgery and, importantly, should direct future, more effective ones.

We present our experience of the modified Dunn procedure in combination with a Ganz surgical dislocation of the hip to treat patients with severe slipped capital femoral epiphysis (SCFE). The aim was to prospectively investigate whether this technique is safe and reproducible. We assessed the degree of reduction, functional outcome, rate of complications, radiological changes and range of movement in the hip. There were 28 patients with a mean follow-up of 38.6 months (24 to 84). The lateral slip angle was corrected by a mean of 50.9° (95% confidence interval 44.3 to 57.5). The mean modified Harris hip score at the final follow-up was 89.1 (sd 9.0) and the mean Non-Arthritic Hip score was 91.3 (sd 9.0). Two patients had proven pre-existing avascular necrosis and two developed the condition post-operatively. There were no cases of nonunion, implant failure, infection, deep-vein thrombosis or heterotopic ossification. The range of movement at final follow-up was nearly normal. This study adds to the evidence that the technique of surgical dislocation and anatomical reduction is safe and reliable in patients with SCFE.

Cite this article: Bone Joint J 2013;95-B:424–9.

Fixed flexion deformities are common in osteoarthritic knees that are indicated for total knee arthroplasty. The lack of full extension at the knee results in a greater force of quadriceps contracture and energy expenditure. It also results in slower walking velocity and abnormal gait mechanics, overloading the contralateral limb. Residual flexion contractures after TKA have been associated with poorer functional scores and outcomes.

Although some flexion contractures may resolve with time after surgery, a substantial percentage will become permanent. Therefore, it is essential to correct fixed flexion deformities at the time of TKA, and be vigilant in the post-operative course to maintain the correction.

Surgical techniques to address pre-operative flexion contractures include: adequate bone resection, ligament releases, removal of posterior osteophytes, and posterior capsular releases. Post-operatively, extension can be maintained with focused physiotherapy, a specially modified continuous passive motion machine, a contralateral heel lift, and splinting.

The incidence of acute and chronic conditions of the tendo Achillis appear to be increasing. Causation is multifactorial but the role of inherited genetic elements and the influence of environmental factors altering gene expression are increasingly being recognised. Certain individuals’ tendons carry specific variations of genetic sequence that may make them more susceptible to injury. Alterations in the structure or relative amounts of the components of tendon and fine control of activity within the extracellular matrix affect the response of the tendon to loading with failure in certain cases.

This review summarises present knowledge of the influence of genetic patterns on the pathology of the tendo Achillis, with a focus on the possible biological mechanisms by which genetic factors are involved in the aetiology of tendon pathology. Finally, we assess potential future developments with both the opportunities and risks that they may carry.

Cite this article: Bone Joint J 2013;95-B:305–13.

Obesity is thought to be an aetiological factor for slipped capital femoral epiphysis (SCFE). We analysed changes in the incidence of SCFE in Scotland over the last two decades. During this period rates of childhood obesity have risen substantially and evidence for a relationship between these changes and the incidence of SCFE was sought.

We found that the incidence of SCFE increased from 3.78 per 100 000 children in 1981 to 9.66 per 100 000 in 2000 (R² = 0.715): a two and a half times increase over two decades. It was seen at a younger age, with a fall in the mean age at diagnosis from 13.4 to 12.6 years for boys (p = 0.007) and 12.2 to 11.6 for girls (p = 0.047). More children under eight years old were seen with SCFE in Scotland in the decade to 2000 than in the previous decade (p = 0.002, R² = 0.346).

A close correlation was observed between rising childhood obesity over the last 20 years in Scotland and an increasing incidence of SCFE.

Symptomatic cobalt toxicity from a failed total hip replacement is a rare but devastating complication. It has been reported following revision of fractured ceramic components, as well as in patients with failed metal-on-metal articulations. Potential clinical findings include fatigue, weakness, hypothyroidism, cardiomyopathy, polycythaemia, visual and hearing impairment, cognitive dysfunction, and neuropathy. We report a case of an otherwise healthy 46-year-old patient, who developed progressively worsening symptoms of cobalt toxicity beginning approximately six months following synovectomy and revision of a fractured ceramic-on-ceramic total hip replacement to a metal-on-polyethylene bearing. The whole blood cobalt levels peaked at 6521 µg/l. The patient died from cobalt-induced cardiomyopathy. Implant retrieval analysis confirmed a loss of 28.3 g mass of the cobalt–chromium femoral head as a result of severe abrasive wear by ceramic particles embedded in the revision polyethylene liner. Autopsy findings were consistent with heavy metal-induced cardiomyopathy.

We recommend using new ceramics at revision to minimise the risk of wear-related cobalt toxicity following breakage of ceramic components.

Cite this article: Bone Joint J 2013;95-B:31–7.

Recently the National Patient Safety Agency in the United Kingdom published a report entitled “Mitigating surgical risk in patients undergoing hip arthroplasty for fractures of the proximal femur”. A total of 26 deaths had been reported to them when cement was used at hemiarthroplasty between October 2003 and October 2008. This paper considers the evidence for using cement fixation of a hemiarthroplasty in the treatment of hip fractures.

Fractures of the distal radius occurring in young adults are treated increasingly by open surgical techniques, partly because of concern that failure to restore the alignment of the fracture accurately may cause symptomatic post-traumatic osteoarthritis in future years. We reviewed 106 adults who had sustained a fracture of the distal radius between 1960 and 1968 and who were below the age of 40 years at the time of injury. We carried out a clinical and radiological assessment at a mean follow-up of 38 years (33 to 42).

No patient had required a salvage procedure. While there was radiological evidence of post-traumatic osteoarthritis after an intra-articular fracture in 68% of patients (27 of 40), the disabilities of the arm, shoulder and hand (DASH) scores were not different from population norms, and function, as assessed by the Patient Evaluation Measure, was impaired by less than 10%. Ordinal logistic regression analysis showed a significant relationship between narrowing of the joint space and extra-articular malunion (dorsal angulation and radial shortening) as well as intra-articular injury. Multivariate analysis revealed that grip strength had fallen to 89% of that of the uninjured side in the presence of dorsal malunion, but no measure of extra-articular malunion was significantly related to either the Patient Evaluation Measure or DASH scores.

While anatomical reduction is the principal aim of treatment, imperfect reduction of these fractures may not result in symptomatic arthritis in the long term, and this should be considered when counselling patients on the risks and benefits of the many treatment options available.

Hypermobility is an acknowledged risk factor for patellar instability. In this case control study the influence of hypermobility on clinical outcome following medial patellofemoral ligament (MPFL) reconstruction for patellar instability was studied.

A total of 25 patients with hypermobility as determined by the Beighton criteria were assessed and compared with a control group of 50 patients who were matched for age, gender, indication for surgery and degree of trochlear dysplasia. The patients with hypermobility had a Beighton Score of ≥ 6; the control patients had a score of < 4. All patients underwent MPFL reconstruction performed using semitendinosus autograft and a standardised arthroscopically controlled technique. The mean age of the patients was 25 years (17 to 49) and the mean follow-up was 15 months (6 to 30).

Patients with hypermobility had a significant improvement in function following surgery, with reasonable rates of satisfaction, perceived improvement, willingness to repeat and likelihood of recommendation. Functional improvements were significantly less than in control patients (p < 0.01).

Joint hypermobility is not a contraindication to MPFL reconstruction although caution is recommended in managing the expectations of patients with hypermobility before consideration of surgery.

We reviewed 27 diabetic patients who sustained a tibial fracture treated with a reamed intramedullary nail and compared them with a control group who did not have diabetes. There were 23 closed fractures and four were open. Union was delayed until after six months in 12 of the 23 (52%) diabetic patients with closed fractures and ten of the 23 (43%) control patients (p = 0.768). In two patients with diabetes (9%), closed tibial fractures failed to unite and required exchange nailing, whereas all closed fractures in the control group healed without further surgery (p = 0.489). In both the diabetic and control groups with closed fractures two patients (9%) developed superficial infections. There were two (9%) deep infections in diabetic patients with closed fractures, but none in the control group (p = 0.489).

Overall, there was no significant difference in the rate of complications between the diabetic patients and the control group, but there was a tendency for more severe infections in patients with diabetes.

The purpose of this paper is to discuss the risk factors, prevention strategies, classification, and treatment of intra-operative femur fractures sustained during primary and revision total hip arthroplasty.