Aims

To present our experience of using a combination of intra-articular osteotomy and external fixation to treat different deformities of the knee.

Acute angulation at the thoracolumbar junction with segmental subluxation of the spine occurring at the level above an anteriorly hypoplastic vertebra in otherwise normal children is a rare condition described as infantile developmental thoracolumbar kyphosis. Three patient series with total of 18 children have been reported in the literature. We report five children who presented with thoracolumbar kyphosis and discuss the treatment algorithm. We reviewed the medical records and spinal imaging at initial clinical presentation and at minimum two-year follow-up. The mean age at presentation was eight months (two to 12). All five children had L2 anterior vertebral body hypoplasia. The kyphosis improved spontaneously in three children kept under monitoring. In contrast, the deformity was progressive in two patients who were treated with bracing. The kyphosis and segmental subluxation corrected at latest follow-up (mean age 52 months; 48 to 60) in all patients with near complete reconstitution of the anomalous vertebra. The deformity and radiological imaging on a young child can cause anxiety to both parents and treating physicians. Diagnostic workup and treatment algorithm in the management of infantile developmental thoracolumbar kyphosis is proposed. Observation is indicated for non-progressive kyphosis and bracing if there is evidence of kyphosis and segmental subluxation deterioration beyond walking age. Surgical stabilisation of the spine can be reserved for severe progressive deformities unresponsive to conservative treatment.

Cite this article: Bone Joint J 2015;97-B:982–7.

Aims

Computer hexapod assisted orthopaedic surgery (CHAOS), is a method to achieve the intra-operative correction of long bone deformities using a hexapod external fixator before definitive internal fixation with minimally invasive stabilisation techniques.

The aims of this study were to determine the reliability of this method in a consecutive case series of patients undergoing femoral deformity correction, with a minimum six-month follow-up, to assess the complications and to define the ideal group of patients for whom this treatment is appropriate.

Patellar instability most frequently presents during adolescence. Congenital and infantile dislocation of the patella is a distinct entity from adolescent instability and measurable abnormalities may be present at birth. In the normal patellofemoral joint an increase in quadriceps angle and patellar height are matched by an increase in trochlear depth as the joint matures. Adolescent instability may herald a lifelong condition leading to chronic disability and arthritis.

Restoring normal anatomy by trochleoplasty, tibial tubercle transfer or medial patellofemoral ligament (MPFL) reconstruction in the young adult prevents further instability. Although these techniques are proven in the young adult, they may cause growth arrest and deformity where the physis is open. A vigorous non-operative strategy may permit delay of surgery until growth is complete. Where non-operative treatment has failed a modified MPFL reconstruction may be performed to maintain stability until physeal closure permits anatomical reconstruction. If significant growth remains an extraosseous reconstruction of the MPFL may impart the lowest risk to the physis. If minor growth remains image intensifier guided placement of femoral intraosseous fixation may impart a small, but acceptable, risk to the physis.

This paper presents and discusses the literature relating to adolescent instability and provides a framework for management of these patients.

Cite this article: Bone Joint J 2017;99-B:159–70.

Aims

Our aim was to investigate the predictive factors for the development of a rebound phenomenon after temporary hemiepiphysiodesis in children with genu valgum.

Aims

Patients undergoing femoral lengthening by external fixation tolerate treatment less well when compared to tibial lengthening. Lengthening of the femur with an intramedullary device may have advantages.

We report five children who presented at the mean age of 1.5 years (1.1 to 1.9) with a progressive thoracolumbar kyphosis associated with segmental instability and subluxation of the spine at the level above an anteriorly-wedged hypoplastic vertebra at L1 or L2. The spinal deformity appeared to be developmental and not congenital in origin. The anterior wedging of the vertebra may have been secondary to localised segmental instability and subsequent kyphotic deformity.

We suggest the term ‘infantile developmental thoracolumbar kyphosis with segmental subluxation of the spine’ to differentiate this type of deformity from congenital displacement of the spine in which the congenital vertebral anomaly does not resolve. Infantile developmental kyphosis with segmental subluxation of the spine, if progressive, may carry the risk of neurological compromise. In all of our patients the kyphotic deformity progressed over a period of three months and all were treated by localised posterior spinal fusion. At a mean follow-up of 6.6 years (5.0 to 9.0), gradual correction of the kyphosis was seen on serial radiographs as well as reconstitution of the hypoplastic wedged vertebra to normality. Exploration of the arthrodesis was necessary at nine months in one patient who developed a pseudarthrosis.

The hip joint is commonly involved in multiple epiphyseal dysplasia and patients may require total hip replacement before the age of 30 years.

We retrospectively reviewed nine patients (16 hips) from four families. The diagnosis of multiple epiphyseal dysplasia was based on a family history, genetic counselling, clinical features and radiological findings. The mean age at surgery was 32 years (17 to 63), with a mean follow-up of 15.9 years (5.5 to 24).

Of the 16 hips, ten required revision at a mean of 12.5 years (5 to 15) consisting of complete revision of the acetabular component in three hips and isolated exchange of the liner in seven. No femoral component has loosened or required revision during the period of follow-up.

With revision for any reason, the 15-year survival was only 11.4% (95% confidence interval 1.4 to 21.4). However, when considering revision of the acetabular shell in isolation the survival at ten years was 93.7% (95% confidence interval 87.7 to 99.7), reducing to 76.7% (95% confidence interval 87.7 to 98.7) at 15 and 20 years, respectively.

Aims

Clinical and radiological data were reviewed for all patients with mucopolysaccharidoses (MPS) with thoracolumbar kyphosis managed non-operatively or operatively in our institution.

Two types of fracture, early and late, have been reported following limb lengthening in patients with achondroplasia (ACH) and hypochondroplasia (HCH).

We reviewed 25 patients with these conditions who underwent 72 segmental limb lengthening procedures involving the femur and/or tibia, between 2003 and 2011. Gender, age at surgery, lengthened segment, body mass index, the shape of the callus, the amount and percentage of lengthening and the healing index were evaluated to determine predictive factors for the occurrence of early (within three weeks after removal of the fixation pins) and late fracture (> three weeks after removal of the pins). The Mann‑Whitney U test and Pearson’s chi-squared test for univariate analysis and stepwise regression model for multivariate analysis were used to identify the predictive factor for each fracture. Only one patient (two tibiae) was excluded from the analysis due to excessively slow formation of the regenerate, which required supplementary measures. A total of 24 patients with 70 limbs were included in the study.

There were 11 early fractures in eight patients. The shape of the callus (lateral or central callus) was the only statistical variable related to the occurrence of early fracture in univariate and multivariate analyses. Late fracture was observed in six limbs and the mean time between removal of the fixation pins and fracture was 18.3 weeks (3.3 to 38.4). Lengthening of the tibia, larger healing index, and lateral or central callus were related to the occurrence of a late fracture in univariate analysis. A multivariate analysis demonstrated that the shape of the callus was the strongest predictor for late fracture (odds ratio: 19.3, 95% confidence interval: 2.91 to 128). Lateral or central callus had a significantly larger risk of fracture than fusiform, cylindrical, or concave callus.

Radiological monitoring of the shape of the callus during distraction is important to prevent early and late fracture of lengthened limbs in patients with ACH or HCH. In patients with thin callus formation, some measures to stimulate bone formation should be considered as early as possible.

Cite this article: Bone Joint J 2014;96-B:1269–73.

Objectives

The development of tibiofemoral angle in children has shown ethnic variations. However this data is unavailable for our population.

We undertook a retrospective analysis of 306 procedures on 233 patients, with a mean age of 12 years (1 to 21), in order to evaluate the use of somatosensory evoked potential (SSEP) monitoring for the early detection of nerve compromise during external fixation procedures for limb lengthening and correction of deformity. Significant SSEP changes were identified during 58 procedures (19%). In 32 instances (10.5%) the changes were transient, and resolved once the surgical cause had been removed. The remaining 26 (8.5%) were analysed in two groups, depending on whether or not corrective action had been performed in response to critical changes in the SSEP recordings. In 16 cases in which no corrective action was taken, 13 (81.2%, 4.2% overall) developed a post-operative neurological deficit, six of which were permanent and seven temporary, persisting for five to 18 months. In the ten procedures in which corrective action was taken, four patients (40%, 1.3% overall) had a temporary (one to eight months) post-operative neuropathy and six had no deficit.

After appropriate intervention in response to SSEP changes, the incidence and severity of neurological deficits were significantly reduced, with no cases of permanent neuropathy. SSEP monitoring showed 100% sensitivity and 91% specificity for the detection of nerve injury during external fixation. It is an excellent diagnostic technique for identifying nerve lesions when they are still highly reversible.

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.

Low bone mass and osteopenia have been described in the axial and peripheral skeleton of patients with adolescent idiopathic scoliosis (AIS). Recently, many studies have shown that gene polymorphism is related to osteoporosis. However, no studies have linked the association between IL6 gene polymorphism and bone mass in AIS. This study examined the association between bone mass and IL6 gene polymorphism in 198 girls with AIS. The polymorphisms of IL6-597 G→A, IL6-572 G→C and IL6-174 G→A and the bone mineral density in the lumbar spine and femoral neck were analysed and compared with their levels in healthy controls. The mean bone mineral density at both sites in patients with AIS was decreased compared with controls (p = 0.0022 and p = 0.0013, respectively). Comparison of genotype frequencies between AIS and healthy controls revealed a statistically significant difference in IL6-572 G→C polymorphism (p = 0.0305). There was a significant association between the IL6-572 G→C polymorphism and bone mineral density in the lumbar spine, with the CC genotype significantly higher with the GC (p = 0.0124) or GG (p = 0.0066) genotypes.

These results suggest that the IL6-572 G→C polymorphism is associated with bone mineral density in the lumbar spine in Korean girls with AIS.

It has been reported that there is an association between Perthes’ disease and poverty. We examined the demographic data of a group of 240 children (263 hips) who presented with Perthes’ disease in Greater Glasgow, where the mean deprivation scores are substantially greater than in the rest of Scotland, to see if this association applied and whether other clues to the aetiology of Perthes’ disease could be found. There were 197 boys and 43 girls; 39 (16.25%) had a family history of Perthes’ disease. Bone age in this series was heavily skewed towards the lower percentiles. The mean number of siblings was 1.9, with 31 (12.9%) being an only child. Maternal age at the birth of the first child showed no preponderance of older mothers. Maternal smoking during and after pregnancy was noted in 132 (55%), which compared with the 52% reported in the population of Greater Glasgow in general. Of the children in our series, 60 (25%) were in social class IV and V. However, this applies to more than half of the population of Greater Glasgow. There was no significant evidence of a preponderance of Perthes’ disease in the most deprived groups. The aetiology of Perthes’ disease is likely to be multifactorial and may include a genetic or deprivation influence resulting in delayed bone age.

We reviewed the medical records of 115 patients with 130 hips with developmental dysplasia with complete dislocation in the absence of a neuromuscular disorder, spontaneous reduction with a Pavlik harness, and a minimum of 14 years’ follow-up. The mean age at the time of harness application was 4.8 months (1 to 12) and the mean time spent in the harness was 6.1 months (3 to 12). A total of 108 hips (83.1%) were treated with the harness alone and supplementary surgery for residual acetabular dysplasia, as defined by an acetabular index > 30°, was performed in 22 hips (16.9%).

An overall satisfactory outcome (Severin grade I or II) was achieved in 119 hips (91.5%) at a mean follow-up of 16 years (14 to 32) with a follow-up rate of 75%. Avascular necrosis of the femoral head was noted in 16 hips (12.3%), seven of which (44%) underwent supplementary surgery and nine (56%) of which were classified as satisfactory. The acetabular index was the most reliable predictor of residual acetabular dysplasia.