Introduction

External fixators are attached to bones with percutaneous pins and wires inserted through soft tissues and bone increasing the risk of infections. Such infections compromise patient outcomes e.g., through pin loosening or loss, failure of fixator to stabilise the fracture, additional surgery, increased pain, and delayed mobilisation. These infections also impact the healthcare system for example, increased OPD visits, hospitalisations, treatments, surgeries and costs. Nurses have a responsibility in the care and management of patients with external fixators and ultimately in the prevention of pin-site infection. Yet, evidence on best practices in the prevention of pin-site infection is limited and variation in pin-site management practices is evident. Various strategies are used for the prevention of pin-site infection including the use of different types of non-medicated and medicated wound dressings. The aim of this retrospective study was to investigate the use of dry gauze or iodine tulle dressings for the prevention of pin-site infections in patients with lower limb external fixators.

Introduction

Angular deformity in the lower extremities can result in pain, gait disturbance, deformity and joint degeneration. Guided growth modulation uses the tension band principle with the goal of treatment being to normalise the mechanical axis. To assess the success of this procedure we reviewed our results in an attempt to identify patients who may not benefit from this simple and elegant procedure.

Introduction

Dual mobility (DM) total hip arthroplasty (THA) prostheses are designed to increase stability. In the setting of primary and revision THA, DM THA are used most frequently for dysplasia and instability diagnoses, respectively. As the use of DM THA continues to increase, with 8,031 cases logged in the American Joint Replacement Registry from 2012–2018, characterizing in vivo damage and clinical failure modes are important to report.

Purpose

Angular deformity in the lower extremities can result in pain, gait disturbance, cosmetic deformity and joint degeneration. Up until the introduction of guided growth in 2007, which has since become the gold standard, treatment for correcting angular deformities in skeletally immature patients had been either an osteotomy, a hemiepiphysiodesis, or the use of staples.

Our aim was to use CT Scanogram to evaluate fibular growth, and thus calculate normal growth velocity, which may aid in determining the timing of epiphysiodesis.

Current understanding of normal lower limb growth and growth prediction originates in the work of Anderson et al published in the 1960s. There now exist several clinical and mathematical methods to aid in the treatment of leg length discrepancy, including the timing of epiphysiodesis. Early research in this area provided limited information on the growth of the fibula. It is now well recognized that abnormal growth of paired long bones may evolve into deformity of clinical significance. Existing work examining fibular growth used plain film radiography only. Computed Tomography (CT) scanogram is now the preferred method for evaluating leg length discrepancy in the paediatric population. We calculated fibular growth for 28 children (n = 28, 16 girls and 12 boys) presenting with leg length discrepancy to our unit. Mean age at presentation was 111.1 months (range 33 – 155 months). For inclusion, each child had to have at least five CT scanograms performed, at six monthly intervals. Fibular length was calculated digitally as the distance from the proximal edge of the proximal epiphysis to the most distal edge of the distal epiphysis. For calculation purposes, mean fibular length was determined from two measurements taken of the fibula. A graph for annual fibular growth was plotted and fibular growth velocity calculated.

CT Scanogram may be used to calculate normal fibular growth in children presenting with leg length discrepancy.

The purpose of this study was to review the outcomes and complications of all circular external fixators (frames) used for the management of sterile and infected fracture non-unions in the lower limb in our institution over a twenty year period.

We retrospectively reviewed a prospectively compiled database of all frames applied in our institution and identified all frames which were applied for acute lower limb trauma. We identified 76 non-unions in 76 patients. There were 22 femoral non-unions and 54 tibial non-unions. Five femoral non-unions and 12 tibial non-unions were confirmed infected. The mean time in frame was 281 days for a sterile non-union and 457 days for an infected non-union. There was a union rate of 87% for sterile non-unions and 71% of infected non-unions at cessation of treatment. Factors associated with persistent non-union included cigarette smoking, soft tissue complications, and excessive pin-site toilet by the patient.

Lower-limb fracture non-unions can be extremely difficult to treat. The patients included in our study had previously undergone more traditional treatments in an attempt to establish union. The results presented demonstrate that circular frames are an excellent treatment modality in non-unions resistant to other forms of treatment. We would recommend this as a first line treatment for patients at higher risk of developing fracture non-union.

The purpose of this study was to review the outcomes of four children with genu valgum secondary to Hurler Syndrome treated with circular external fixators (frames) for angular correction.

We retrospectively reviewed the medical and radiographic records of four children with Hurler Syndrome and genu valgum treated with frames. Three children had simultaneous bilateral tibial corrections. The fourth child had unilateral femoral correction. The mean age of the children was 14 years at application of frame. Mean duration of frame was 113 days for the tibial frames, and the femoral frame remained in-situ for 150 days. Correction was assessed clinically, and radiologically with x-rays and CT scannograms, with excellent results in all four cases. The complexities of each individual case necessitated specific and individualised treatment for each child. Complications included further deformities arising in treated and un-treated long-bones both during and after application of frame.

Prior to the introduction of bone marrow transplantation, the average life expectancy of children with Hurler Syndrome was seven years. With bone marrow transplantation, affected children are now living much longer, and many develop characteristic long bone deformities in their lower limbs. These deformities are progressive and can be multifocal and polyostotic. Managament can be extremely challenging, and prior reports of management with hemiepiphysiodesis with staples and 8-plates have been mixed. We believe that this is the first series of circular frame lower limb reconstruction in children with Hurler Syndrome. The flexibility and adaptability of frames confers a unique advantage in the management of these complex deformities.

The purpose of this study was to review the outcomes and complications of all circular external fixators (frames) used for the management of acute lower limb trauma in our institution over a twenty year period.

We retrospectively reviewed a prospectively compiled database of all frames applied in our institution and identified all frames which were applied for acute lower limb trauma. We identified 68 fractures in 63 patients. There were 11 femoral fractures and 57 tibial fractures. All fractures were classified using the AO Classification system, and most fractures were Type C fractures. We used an Ilizarov frame in 53 patients and a Taylor Spatial Frame in 15 patients. The mean time in frame was 365 days for a femoral fracture and 230 days for a tibial fracture. There were five tibial non-unions giving an overall union rate of 93%. Factors associated with non-union included high energy trauma and cigarette smoking.

The vast majority of lower limb fractures can be treated using ‘conventional’ methods. Complex fractures which are not amenable to open reduction and internal fixation or cast immobilisation can be treated in a frame with excellent results. The paucity of published reports regarding the use of frames for complex trauma reflects the under-utilisation of the technique.

Introduction

Developments in the use of ultrasound during pregnancy for assessment of fetal spine abnormalities indicate a need for accurate information about the antenatal development of the vertebral column. The published work is deficient in this regard, with available data examining only the period of 8–26 weeks. The aims of this study are to establish antenatal spine growth curves with fetal radiographs, to establish growth velocity curves for each anatomical spinal, region and to calculate the multiplier factor during antenatal life.

Introduction

Idiopathic scoliosis is a lateral curvature of the spine >10° as measured on a frontal plane radiograph by the Cobb angle. Important variables in assessing the risk of curve progression include a young age at presentation, female sex, a large amount of growth remaining, the rate of growth, the curve magnitude, and the curve location. Curves >20° have an inherently low risk of progression. Surgery is indicated for curves >50° or rapidly progressing curves. The timing of surgery is paramount in order to intervene in cases where rapid progression is evident to prevent further deterioration. There is a greater likelihood for more complex surgery to be required in major curves. At present, there are severe restrictions on resources to cater for patients with scoliosis. As a result, patients spend excessive periods on waiting lists prior to having their procedure. The aim of this study is to analyse the progression of curves of patients while on the waiting list and assess the cost implications of curve deterioration.

Background: Ilizarov and Taylor Spatial Fixators are commonly used in the management of complex fractures and in the management of fracture non-union at our institute. We aim to review 15 years of circular frame use by a single surgeon to assess the incidence of successful treatment of fractures and fracture non-unions.

Methods: We retrospectively reviewed the case notes, theatre lists, and radiology records of all patients who had been treated with a circular fixator over the past 15 years. We identified 134 procedures in 114 patients where a circular fixator was used for fracture stabilisation or treatment of non-union of fracture. We documented the length of time each frame was in-situ and the outcome of treatment.

Results: We identified 60 fractures in 54 patients and 74 fracture non-unions in 73 patients. Of the fracture non-unions 20 were known to be infected and 74 were considered sterile. Average length of time with a fixator in -situ was 243 days for the fracture group, 301 days for the sterile non-union group, and 343 days for the infected non-union group. 50 of 60 (83.3%) fractures united satisfactorily and four mal-united. Five fractures developed sterile non-union and one developed infected non-union. Of 54 sterile non-unions 42 united (77.8%), five with significant mal-union. Three were thought to have united but re-fractured after removal of frame. Eight failed to unite and one patient died of unrelated cause with fixator in-situ. Of 20 infected non-unions, fourteen united (70%), three with significant mal-union. One non-union was thought to have healed but re-fractured when the fixator was removed. Four remained infected and failed to unite and one failed due to soft tissue complications not associated with the fixator.

Conclusions: Circular External Fixators are an appropriate method of treatment for complex fractures and fractures that have failed to unite when treated with alternative fixation devices.

Background: Diagnostic injection plays an increasing role in the diagnosis of foot and ankle pathology. Joint communications have been reported in several studies, and it has been suggested they may impact on clinical management.

Method: We analysed the findings of 389 arthrograms of the foot and ankle, identifying any joint communications noted on imaging. A case note review was then undertaken on a subset of 153 of these patients with the aim of establishing the effect of injection findings on clinical management. All injections were performed and reported by a single consultant radiologist.

Results: Joint communications were seen in 24% of patients with an equal distribution amongst males and females. Rates of individual joint communications were consistent with those previously published.

Injection studies had an impact on subsequent management in 88% of cases. Symptoms resolved with injection alone in 28% of patients with no communication versus 8% in those with a communication. Surgical plans were changed in over 20% of cases if a joint communication was found. There were no major complications reported (Joint sepsis or contrast allergy).

Conclusion: This study confirms the presence of multiple joint communications within the foot and ankle, and highlights the importance of arthrography in the diagnosis of pathology.

We would recommend joint injection be considered in all patients, especially if joint fusion is being considered. Contrast should be used in all cases to demonstrate any potential communications, which should be taken into consideration when surgical management plans are formulated. A significant number of patients will experience resolution of symptoms from injection alone, with no further intervention needed.

Introduction: Percutaneous epiphysiodesis is a well established procedure in the treatment of leg length discrepancy. Many techniques have been described ranging from an open technique to the more recently described percutaneous technique. This study assesses the percutaneous single portal technique, in combined distal femoral and proximal tibial lower limb epiphysiodesis, performed by a single surgeon.

Methods: We performed a retrospective review of cases performed in a single institution by a single surgeon from 1994 to present. A total of 45 combined epiphysiodesis were performed. 40 patients qualified for the study group with at least 2 years follow up. There were 19 female and 21 male patients, with the operative side equally shared between left and right.

Results: The mean predicted leg length discrepancy using the Mosley Straight Line Graph was 2.43 cm. The mean final leg length discrepancy, at an average follow up of 31 months, was 1.5 cm with a range of 0 to 2.81 cm. There were no angular deformities at follow up. One female patient had a knee effusion which resolved spontaneously. One male patient complained of anterior knee pain initially post surgery however this resolved at final follow up without treatment. The majority of patients (n=34) were inpatients, however more recently this procedure has been successfully carried out as a day case (n=6).

Discussion: Percutaneous epiphysiodesis has been accepted as a standard technique to treat leg length discrepancy of 2 cm to 5 cm. Several techniques have been described in the literature with varying complication rates. This study shows that single portal combined epiphysiodesis is successful and has a relatively low complication rate.

Introduction: Bone transport, or distraction osteogenesis, is a recognised technique to reconstruct extensive bony defects resulting from excision of bony tumours. Ilizarov demonstrated bone formation under tension allowing the movement of a free segment of living bone to fill intercalary defects. This study assesses the use of bone transport in the management of patients with resectable long bone tumours.

Methods: We retrospectively reviewed patients who underwent bone transport in two institutions, performed by a single surgeon. A total of 14 patients were included in the study. There were 11 males and 3 females. Histological results demonstrated osteosarcoma (n=7), Ewing’s sarcoma (n=6), and parosteal chondrosarcoma (n=1). The site of the tumour was the femur and tibia in 8 and 6 cases respectively.

Results: Bone transport was fully completed in 9 patients. Of the 5 patients remaining, 3 are currently in cast, 1 is currently undergoing tibial lengthening, and 1 patient died from local recurrence and distant spread of disease. The average length of bone resected in the tibia was 11 cm (range 8–15 cm), while in the femur the average was higher at 16.5 cm (range 12–27 cm). All patients underwent autologous bone grafting of their docking site from either the anterior or posterior iliac crest on the ipsilateral side. The average time in frame was 24.8 months. One patient undergoing tibial bone transport fell and sustained an ipsilateral supracondylar femoral fracture which was successfully treated with an external ring fixator.

Discussion: Bone transport is a recognised method of reconstructing extensive bony defects and is beneficial for patients with a good prognosis. It is a specialised technique and requires a multidisciplinary approach. Other techniques can be less time consuming however distraction osteogenesis avoids the complications associated with prosthetic or allograft replacements.

Introduction: A parameter in surface topography was developed to measure left-right differences in back surface of different scoliosis patterns, and to relate these to biological asymmetry and the evolution of deformity. Because of the close association between scoliosis and growth, the hypothesis that scoliosis is growth, that it affects not just the spine but the whole body and that it falls into well-described biological patterns of asymmetry, was explored.

Methods: The new measure compares the positions of three points (mid way between the first thoracic vertebra and axilla, and one and two thirds from axilla to posterior superior iliac spines) on either side of the mid-line, reflecting right onto left and expressing the displacement along Cartesian axes in millimetres. The purpose is to measure size and growth differences at diagnosis and during follow-up. Statistical analysis was of prospectively collected topographic, radiographic and clinical data. There were three groups, all female: 1. mild asymmetry (N=84, no radiograph); 2. thoracic (N=65, mean Cobb angle 61.4°±19.5) and 3. thoracolumbar or lumbar (N=40, mean Cobb angle was 51.8°±23.0). Comparisons were made between each group and theoretically perfect symmetry (test value zero). Correlations with Cobb angle change over time were analysed.

Results: Groups one and three showed directional asymmetry in the coronal plane only, and were not statistically different from each other. Group two showed directional asymmetry at all levels, the side of the scoliosis convexity being larger in all three dimensions (left-right, antero-posterior and cranio-caudal). Changes in Cobb angle correlated with statistical significance with change in the vertical height of the convex side.

Conclusions: This topographic measure was developed specifically to quantify the asymmetry of the back surface, to assign it to a biological pattern and to observe how it might change during growth and scoliosis evolution. All levels of asymmetry, the minor as well as the true scoliosis, showed directional asymmetry (normal distribution of left-right differences about a mean that is not zero, genetically determined) which suggests an origin of scoliosis lying in the biology of growth and the evolution of morphology, rather than in a particular disease process. This asymmetry does not cause scoliosis: it is the result of asymmetric growth processes, it is scoliosis. The relevance of this view is that it obviates the need for an identifiable disease process, as scoliosis is a non-specific developmental response to physiological stress. It is the destabilising of the genetic control “programme” that operates in the growing organism to produce an adult phenotype which is an accurate expression of its genotype. This interpretation can explain observations of natural history that currently cause problems viz. the association with growth and development, lateralisation, increased incidence with other medical conditions, and female predominance, the recurrence of deformity after surgical correction and perhaps even the difficulty in reaching a final conclusion on the efficacy of brace treatment.

Background: Adolescent idiopathic scoliosis has been intensively studied, but is still not understood. It is the paradoxical co-existence of rude health and gross deformity in the same individual that needs to be explained. The essence of scoliosis is asymmetry, and bilateral asymmetries in many anatomical features have been described in association with it. Measurement of asymmetry in back surface made possible by surface topography can explore this aspect and throw light on the evolution of the deformity as the Cobb angle changes.

Objective: To quantify the asymmetry of the back surface in scoliosis and the lesser non-scoliosis deformities.

Methods: Routine clinical material (patient demographics, radiography and surface topography) was analysed. Changes in body symmetry were quantified, using a topographic measure that calculates the difference, in three dimensions and at three levels, between the left and right sides of the back across the mid-line (natal cleft to first thoracic vertebra). Girls only (to eliminate any effect from sexual dimorphism) with all presenting degrees of deformity from barely failing the forward bend test through mild scoliosis unconfirmed by radiograph (Group 1, N=311) to documented scoliosis (Cobb angle => 10°), apex at T12 or below (Group 2 and apex above T12 (Group 3).

Results: All groups showed significant departures from bilateral symmetry. Groups 1 and 2 were similar, in that the left side was taller but narrower than the left. In Group 3, the side of curve convexity was taller than the concave side. This was reversed in left thoracic scoliosis patterns and was seen to increase over time with progression of the Cobb angle.

Discussion: It has long been acknowledged that scoliosis and growth are inseparable, but studies have failed to demonstrate a disease process or endocrine imbalance. These findings suggest that it is not a disorder superimposed on growth, but that growth itself causes the deformity. The spine, the whole trunk, in fact, is crooked because it grew that way. Only a small discrepancy in left-right symmetry is sufficient, over time and during periods of rapid growth, to produce both the curve and the rotation.

Conclusion: Scoliosis is neither a disease nor a mechanically induced aberration. It results from asymmetrical growth, which occurs at the cellular and molecular level.

A 2002 study by Goldberg et al showed that surgery before age 10 for infantile onset idiopathic scoliosis (diagnosis < 4 years, Cobb angle => 10°) preserved neither respiratory function nor cosmesis, and has not been contradicted. In 2005, Mehta re-emphasised scoliosis correction by serial cast-bracing, while Thompson et al reported satisfactory results with growing rods. An analysis of the status quo of a cohort of patients with infantile idiopathic scoliosis (other diagnoses and syndromes excluded), managed by cast-bracing, was undertaken, asking whether interim progress was acceptable or demanded a change of protocol.

Of 35 patients born between October 1993 and December 2002,15 have completely resolved, age at diagnosis 1.6 ± 0.96 years, Cobb angle 20.3°±11.9, RVAD 11.1°±13.8, latest age 4.1± 2.3. 20 were prescribed cast-bracing, age at diagnosis 1.8±0.9 years, Cobb angle 47.3°±12.6, RVAD 29.6±24.5, age at treatment was 2.1±1.0 years. Cobb angle (p< 0.001) and RVAD (p=0.001) were larger in the treated group, but age at presentation was the same (p=0.473). Surgery was performed on 3 children unresponsive to initial casting, at ages 3.2, 3.6 and 3.7, and in 3 at ages 8.6, 10.1 and 11 years. 3 children, aged 6.0, 8.1 and 11.3 are out of brace with straight spines and 11 are stable in brace.

Infantile idiopathic scoliosis seems programmed to resolve or progress according to initial severity and in line with growth rate. Those who respond to casting in infancy generally remain stable until near puberty when surgery is uncontroversial. Those who progress relentlessly and immediately in cast remain the issue, as reports of newer methods include a wide range of ages and diagnoses and give their outcome in terms of Cobb angle only. It has not yet been shown that any treatment will alter their prognosis so constant analysis of all outcome parameters is essential.

It is customary to analyse scoliosis as a mechanical failure: first there is a straight spine (=normal), then an habitual and collapsing posture (=disease) and finally, structural remodelling (Hueter-Volkmann effect = scoliosis). This hypothesis makes two practical predictions:

There is a disease process causing the pathological posture. The purpose of gatherings such as this is to identify this pathology, thus far without success.

The failure of school scoliosis screening to achieve this end is well documented, but the consequence for the underlying hypothesis has not been analysed. Screening failed, not because it was unable to detect scoliosis, but because scoliosis did not behave as the hypothesis predicted.

Disease process: All theories presume some form of neurological or muscular deficit as the final pathway but while the variety is wide, e.g. (historically) anterior poliomyelitis; more recently proprioceptive defect, melatonin or calmodulin disorder, there is no clear evidence for such a deficit in adolescent idiopathic scoliosis (AIS). Of 1342 screening referrals to this centre, 10 had a neurological diagnosis (most of which were already known to the patients) and 598 had radiologically confirmed AIS. In contrast, 1707 referrals to the general clinics included 410 syndromic cases and 420 AIS. Patients with a neurological problem, by and large, find their own way to medical attention. The hypothesis does not explain the natural history or the aetiology, and awkward observations, such as the association with growth (Goldberg et al Spine.18(5):529–535.1993, Eur Spine J.2:29–36.1993 and, most recently, Ylikoski M. Journal of Pediatric Orthopaedics B.14:320–324, 2005) or the higher incidence in ballet dancers (Warren et al. New England Journal of Medicine.314(21):1348–1353.1986) and rhythmic gymnasts (Tanchev et al. Spine.25(11):1367–1372.2000) are ignored.

Screening: Screening programmes (e.g. Goldberg et al., Spine.20(12):1368–1374, 1995) showed that there was no precise demarcation between “scoliosis” and “normal,” and that there was no benefit in terms of the need for surgical correction from screening or bracing, (Goldberg et al. Spine.26(1):42–47, 2001).

Discussion: his information has been in the public domain for some years and, in the meanwhile, there have been huge advances in biology and medicine which must have relevance. When the predictions of a hypothesis are not confirmed, that hypothesis must at least be re-examined, and it is not necessary to wait until a replacement can be suggested. The undisputed aspects of scoliosis, such as association with growth rate and maturation, lateralisation, gender predominance, normal distribution of Cobb angle and asymmetry over the wider population, essential health and normality of those with even severe deformity, increased incidence in other conditions, all suggest a different model. This is an opportune time to pause and reconsider the underlying model of scoliosis in the light of what we have learned about scoliosis and what is now known in other disciplines about how morphology is determined and evolved.

Background: It is commonly observed that a good correction of the Cobb angle at scoliosis surgery is accompanied by an acute asymmetry of shoulder height. Kuklo et al in 2002 described (Spine. 26(18):1966–1975) spontaneous reversal of this, using radiographic measures and patient questionnaires.

Objective: To determine the incidence and extent of shoulder-imbalance before posterior spinal surgery and to ascertain its outcome, using radiographic and topographic measures.

Methods: Patients with right thoracic adolescent idiopathic scoliosis who had undergone corrective posterior spinal fusion by one surgeon were identified. Pre- and all postoperative spinal radiographs and surface topography were evaluated and correlated. Any effect from concomitant anterior release procedures was sought.

Results: Sixty six patients were identified, 56 girls and 10 boys. Their pre-operative major Cobb angle was 73°±14.0 and mean correction was 38.8°±12.333 (56%). Before surgery, surface topography showed the mid-point of the right shoulder to be at a mean or 18.3mm.±10.9 higher than the equivalent left point; eight days later, the difference was −6.7 mm. ±9.68, a mean change of 25.9mm±11.8. At six months, it was −5.1 ±6.86, statistically unchanged. At two years, it was −2.16 (p=0.051) and at three years, 1.76± 6.53 and indistinguishable from zero or perfect balance. The difference between pre-operative and final shoulder level difference was 19.54mm.±9.09. The Cobb angle of the compensatory upper thoracic curve was not significantly changed throughout. There was no statistically significant difference in shoulder height between patients undergoing single or two-stage surgery, either before or at any stage after.

Discussion and conclusion: Correction of post-operative shoulder imbalance does occur spontaneously, as reported by Kuklo et al. and is not a function of spinal accommodation to the new anatomy.

Introduction: Therapeutic bone marrow transplantation has increased survival in Hurler syndrome, but the effects on musculoskeletal development remain unclear. Long term reports on mobility are poor, with many patients gradually losing walking ability in later childhood secondary to hip subluxation and joint contractures. As previous cohorts are small, data is limited.

Methods: We detail the follow up of twenty patients over a mean of 94 months (range 1 – 17.4 years). Radiographs were assessed for hip dysplasia using acetabular angle of Sharp, centre edge angle of Wiberg and tibiofemoral shaft angle. Clinical examination was performed at an annual multidisciplinary assessment by one clinician and compared against age matched controls. 3D gait analysis was performed on eight older children, and deviance in kinematic variables was plotted against controls with Mann-Whitney U test for statistical analysis.

Results: All patients demonstrated characteristic ace-tabular dysplasia. Fourteen patients have undergone containment surgery at a mean of 4.4 years. Innominate osteotomy is an essential part of this. Mean preoperative acetabular angle was reduced from 34 ± 4° to 22 ± 3°. Femoral head containment is maintained, with mean centre edge angle in older patients 39 ± 7°. Genu valgum is observed early, and five patients underwent medial epiphyseal stapling at a mean of 7.8 years, decreasing tibiofemoral angle by a mean of 8.0°. All patients are currently independently mobile, with restriction of internal hip rotation being the only significant clinical finding (P< 0.001). Joint contractures were not noted. Walking speed and stride length were comparable to controls, but endurance is reduced by about one quarter. Gait analysis demonstrates a characteristic pattern, with anterior pelvic tilt secondary to thoracolumbar gibbus, relative hip flexion throughout the gait cycle, valgus knees and compensatory pronated feet; all measured deviations were significant (P< 0.001).

Conclusions This large group maintained successful hip containment and good mobility throughout childhood. Innominate osteotomy alone has been used recently. Despite plain film appearance, genu valgum is a functional problem in gait, and we would anticipate greater use of corrective stapling in the future. This is the first report of gait analysis in Hurler syndrome, and features specific to the condition are described.