Lower-limb lengths and angles in children older than six years: Reliability and reference values by EOS® stereoradiography.

BACKGROUND: Lower-limb alignment in children is classically assessed clinically or based on conventional radiography, which is associated with projection bias. Low-dose biplanar radiography was described recently as an alternative to conventional imaging. The primary objective of this study was to assess the reliability of length and angle values inferred from 3D reconstructions in children seen in everyday practice. The secondary objective was to obtain reference values for goniometry parameters in children. HYPOTHESIS: 3D reconstructions can be used to assess the lower limbs in children. MATERIAL AND METHODS: The paediatric reliability study was done in 18 volunteers who were divided into three groups based on whether they were typically developing (TD) children, had skeletal development abnormalities, or had cerebral palsy. The reference data were obtained in 129 TD children. Each study participant underwent biplanar radiography with 3D reconstruction performed by experts and radiology technicians. Goniometry parameters were computed automatically. Reproducibility was assessed based on the intra-class coefficient (ICC) and the ISO 5725 standard (standard deviation of reproducibility, SDR). RESULTS: For length parameters, the ICCs ranged from 0.94 to 1.00 and the SDR from 2.1 to 3.5mm. For angle parameters, the ICC and SDR ranges were 0.60-0.95 and 0.9°-4.6°, respectively. No significant differences were found across experts or radiology technicians. Age-specific reference data are reported. DISCUSSION: These findings confirm the reliability of low-dose biplanar radiography for assessing lower-limb parameters in children seen in clinical practice. In addition, the study provides reference data for commonly measured parameters. LEVEL OF EVIDENCE: IV.

EOS analysis of lower extremity segmental torsion in children and young adults.

INTRODUCTION: Lower limb torsion varies substantially among healthy children during growth. Values reported in the literature to date have been obtained using semi-quantitative clinical or 2D measurement methods. Quantitative 3D measurement would help determine the physiological range of lower limb torsion. Low-dose stereoradiography with 3D reconstruction provides a good alternative. Its use increases in pediatrics because of radiation minimization. Previous studies have shown accurate and reproducible results of lower limbs reconstruction in adults and children but the torsional parameters haven't been measured yet. The present study reports the values of lower limb segmental torsion and its course during growth in a cohort of healthy children and young adults using the EOS low-dose biplanar X-ray. HYPOTHESIS: EOS 3D reconstruction is an accurate and reproducible method to measure the torsional parameters in children. MATERIALS AND METHODS: Femoral torsion (FT) and tibial torsion (TT) were studied on 114 volunteers (228 lower limbs) from 6 to 30 years of age divided by age into 5 groups. The EOS™ acquisitions were obtained in subjects standing with their feet offset. RESULTS: Mean FT decreased during growth, passing from 21.6° to 18°, whereas mean TT increased from 26.8° to 34.7°. There was a statistically significant difference between the 2 extreme age groups, but no difference was found between any other age groups. The ICC for intra-observer reproducibility was 0.96 and 0.95 for FT and TT for the first operator, and 0.79 and 0.83 for the second operator respectively. The ICC for inter-observer reproducibility was 0.84 and 0.82 respectively. DISCUSSION: The course of lower limb segmental torsion observed was consistent with literature reports based upon clinical and 2D measurements. 3D reconstruction of EOS low-dose biplanar imaging appears to be a safe and reliable tool for lower limbs measurements, especially for investigating lower limb segmental torsion in children and adults. LEVEL OF EVIDENCE: Level IV.

Mazabraud's syndrome. A case with multiple myxomas.

Mazabraud's syndrome is defined as the combination of one or more intramuscular myxomas and fibrous dysplasia of bone. The diagnosis is important given the increased risk of malignant transformation of the bone lesions. We report a case in a 56-year-old patient with a 14-year follow-up during which multiple surgical procedures were required to remove myxomas (present at more than 15 sites). The resected myxomas were large and progressive. Unique features in this case include the long follow-up and the number of myxomas considerably above the average for this disease. Eighty other cases of Mazabraud's syndrome have been reported. The condition predominantly affects middle-aged women (mean age, 44 years). The bone lesions may be monostotic or polyostotic. Mazabraud's syndrome may be difficult to distinguish from soft-tissue sarcoma or neurofibromatosis. Identification of the underlying genetic abnormality provides diagnostic confirmation, as shown in our patient. The management consists in surgery to remove the myxomas and magnetic resonance imaging at regular intervals to monitor the lesions.

Efficacy and late complications of percutaneous epiphysiodesis with transphyseal screws.

Percutaneous epiphysiodesis using transphyseal screws (PETS) has been developed for the treatment of lower limb discrepancies with the aim of replacing traditional open procedures. The goal of this study was to evaluate its efficacy and safety at skeletal maturity. A total of 45 consecutive patients with a mean skeletal age of 12.7 years (8.5 to 15) were included and followed until maturity. The mean efficacy of the femoral epiphysiodesis was 35% (14% to 87%) at six months and 66% (21% to 100%) at maturity. The mean efficacy of the tibial epiphysiodesis was 46% (18% to 73%) at six months and 66% (25% to 100%) at maturity. In both groups of patients the under-correction was significantly reduced between six months post-operatively and skeletal maturity. The overall rate of revision was 18% (eight patients), and seven of these revisions (87.5%) involved the tibia. This series showed that use of the PETS technique in the femur was safe, but that its use in the tibia was associated with a significant rate of complications, including a valgus deformity in nine patients (20%), leading us to abandon it in the tibia. The arrest of growth was delayed and the final loss of growth at maturity was only 66% of that predicted pre-operatively. This should be taken into account in the pre-operative planning.

Non-simultaneous bilateral hip fracture: epidemiologic study of 241 hip fractures.

INTRODUCTION: Hip fractures are an important public health problem given their growing incidence as well as their functional and vital repercussions. With longer survival, patients with a contralateral fracture are increasingly numerous. The objective of this study was to investigate the bilateralization of hip fractures in terms of anatomic location and time to the second fracture. HYPOTHESIS: Contralateral fractures are of the same anatomical type as the primary fractures. PATIENTS AND METHODS: This was a retrospective epidemiological study on all patients managed for hip fractures between January 2007 and May 2008. Each case of bilateralization was studied. RESULTS: We included 241 patients in the study. The mean age at occurrence of the primary fracture was 83.3 years (range, 60-99 years). The distribution showed 45.6% true femoral neck fractures and 54.4% trochanteric fractures. Twenty-six of the 241 patients had already suffered from a hip fracture (10.8%). This fracture was the same type as the recent fracture in 80.8% of the cases. The mean time between the two fractures was 5.6 years (range, 1-277 months). DISCUSSION: The contralateral fractures were the same anatomical type as the primary fracture in eight out of ten patients and the symmetry remains intact in 64-83% depending on the series. The fracture occurred on average within 5 years of the first hip fracture. In cases of asymmetry, the second fracture was more often a trochanteric fracture. The causes explaining this symmetry are several and are poorly known. The risk factors are numerous and their prevention is essential (acting on the patient's environment to prevent falls, rehabilitation to reestablish autonomy after the first fracture, and preventive treatment of osteoporosis), although these notions are often ignored by surgeons. LEVEL OF EVIDENCE: IV, retrospective study.