The use of minimally invasive techniques in multi-level surgery for children with cerebral palsy

This study compares the initial outcomes of minimally invasive techniques for single-event multi-level surgery with conventional single-event multi-level surgery. The minimally invasive techniques included derotation osteotomies using closed corticotomy and fixation with titanium elastic nails and percutaneous lengthening of muscles where possible. A prospective cohort study of two matched groups was undertaken. Ten children with diplegic cerebral palsy with a mean age of ten years six months (7.11 to 13.9) had multi-level minimally invasive surgery and were matched for ambulatory level and compared with ten children with a mean age of 11 years four months (7.9 to 14.4) who had conventional single-event multi-level surgery. Gait kinematics, the Gillette Gait Index, isometric muscle strength and gross motor function were assessed before and 12 months after operation.

The minimally invasive group had significantly reduced operation time and blood loss with a significantly improved time to mobilisation. There were no complications intra-operatively or during hospitalisation in either group. There was significant improvement in gait kinematics and the Gillette Gait Index in both groups with no difference between them. There was a trend to improved muscle strength in the multi-level group. There was no significant difference in gross motor function between the groups.

We consider that minimally invasive single-event multi-level surgery can be achieved safely and effectively with significant advantages over conventional techniques in children with diplegic cerebral palsy.

Early management of pathological fractures in children

The management of pathological fractures in children remains controversial. The indications for surgical treatment are unclear and the need for histological diagnosis before or after definitive treatment is not clearly defined. We reviewed retrospectively the records of all patients under the age of 16 years who presented over the past 7 years with a fracture as the first manifestation of bone pathology. There were 23 patients (16 boys and 7 girls) of an average age of 12 years and 2 months (range 4.1-15.8 years). There were nine cases of fracture through a simple bone cyst, five cases of fibrous dysplasia, two giant cell tumours, three aneurysmal bone cysts, one chondroblastoma, and three cases of Ewings sarcoma. After review of our cases we propose a simple algorithm for the safe early management and assessment of paediatric pathological fractures. We recommend that primary fixation of pathological fractures should be avoided until histological diagnosis is obtained. Most lesions should eventually be biopsied. However, if radiographic appearances are reassuringly benign, biopsy can be delayed until conservative fracture management is completed. Definitive treatment of benign lesions with protective intra medullary nailing or curettage and grafting can follow frozen section under the same anaesthetic.

Prediction of the hip joint centre in adults, children, and patients with cerebral palsy based on magnetic resonance imaging

The location of the hip joint centre (HJC) is required for calculations of hip moments, the location and orientation of the femur, and muscle lengths and lever arms. In clinical gait analysis, the HJC is normally estimated using regression equations based on normative data obtained from adult populations. There is limited relevant anthropometric data available for children, despite the fact that clinical gait analysis is predominantly used for the assessment of children with cerebral palsy. In this study, pelvic MRI scans were taken of eight adults (ages 23-40), 14 healthy children (ages 5-13) and 10 children with spastic diplegic cerebral palsy (ages 6-13). Relevant anatomical landmarks were located in the scans, and the HJC location in pelvic coordinates was found by fitting a sphere to points identified on the femoral head. The predictions of three common regression equations for HJC location were compared to those found directly from MRI. Maximum absolute errors of 31 mm were found in adults, 26 mm in children, and 31 mm in the cerebral palsy group. Results from regression analysis and leave-one-out cross-validation techniques on the MRI data suggested that the best predictors of HJC location were: pelvic depth for the antero-posterior direction; pelvic width and leg length for the supero-inferior direction; and pelvic depth and pelvic width for the medio-lateral direction. For single-variable regression, the exclusion of leg length and pelvic depth from the latter two regression equations is proposed. Regression equations could be generalised across adults, children and the cerebral palsy group.

Assessment of sub-division of plantar pressure measurement in children

Methods for the measurement of plantar pressure are poorly defined particularly when describing sub-sections of the plantar surface of the foot in the presence of deformity. The aim of this study was to assess foot pressure measurement in healthy children, using an automatic technique of sub-area definition that has the potential for objective evaluation of treatment of foot deformity. Twelve healthy children were examined on three occasions. Plantar pressure data were collected and time synchronised with force plate and stereophotogrammetric data. The footprint was divided into five sub-sections by using the position of the markers on the foot at mid-stance projected onto the pressure footprint. Repeatability for peak pressure and peak force was assessed. Automatic sub-area definition based on marker placement was found to be reliable in healthy children. A comparison of results revealed that peak vertical force was a more consistent measure than peak pressure for each of the five sub-areas. This suggests that force may be a more appropriate measurement for outcome studies.

Dynamic foot movement in children treated for congenital talipes equinovarus

The aim of this study was to define objectively gait function in children with treated congenital talipes equinovarus (CTEV) and a good clinical result. The study also attempted an analysis of movement within the foot during gait. We compared 20 children with treated CTEV with 15 control subjects. Clinical assessment demonstrated good results from treatment. Three-dimensional gait analysis provided kinematic and kinetic data describing movement and moments at the joints of the lower limb during gait. A new method was used to study movement within the foot during gait. The data on gait showed significantly increased internal rotation of the foot during walking which was partially compensated for by external rotation at the hip. A mild foot drop and reduced plantar flexor power were also observed. Dorsiflexion at the midfoot was significantly increased, which probably compensated for reduced mobility at the hindfoot. Patients treated for CTEV with a good clinical result should be expected to have nearly normal gait and dynamic foot movement, but there may be residual intoeing, mild foot drop, loss of plantar flexor power with compensatory increased midfoot dorsiflexion and external hip rotation.

The classification of congenital talipes equinovarus

We have assessed the reliability of four classification systems for club foot. Four observers evaluated nine children (18 feet) at different stages in the first six months of life, a total of 180 examinations. Each observer independently assessed all feet according to the classification systems described by Catterall, Diméglio et al, Harrold and Walker, and Ponseti and Smoley.

The variation between observers was assessed using the kappa test which for no more agreement than chance has a value of 0, and for complete agreement between observers a value of 1. The kappa values varied between 0.14 and 0.77 depending on which classification system was used. The system of Diméglio et al was found to have the greatest reliability.

Our findings suggest that current classification systems for the analysis of congenital talipes equinovarus are not entirely satisfactory.

Kinematic analysis of a multi-segment foot model for research and clinical applications: a repeatability analysis

An unbiased understanding of foot kinematics has been difficult to achieve due to the complexity of foot structure and motion. We have developed a protocol for evaluation of foot kinematics during barefoot walking based on a multi-segment foot model. Stereophotogrammetry was used to measure retroreflective markers on three segments of the foot plus the tibia. Repeatability was evaluated between-trial, between-day and between-tester using two subjects and two testers. Subtle patterns and ranges of motion between segments of the foot were consistently detected. We found that repeatability between different days or different testers is primarily subject to variability of marker placement more than inter-tester variability or skin movement. Differences between inter-segment angle curves primarily represent a shift in the absolute value of joint angles from one set of trials to another. In the hallux, variability was greater than desired due to vibration of the marker array used. The method permits objective foot measurement in gait analysis using skin-mounted markers. Quantitative and objective characterisation of the kinematics of the foot during activity is an important area of clinical and research evaluation. With this work we hope to have provided a firm basis for a common protocol for in vivo foot study.

Collagen accumulation in muscles of children with cerebral palsy and correlation with severity of spasticity

Muscle function often becomes progressively more compromised in children with spastic cerebral palsy, leading to reduced mobility. This study aimed to examine the role that muscle connective tissue plays in this process. Severity of spasticity as determined by a range of clinical measures was assessed in 26 children (14 males 12 females; age range 4 to 17 years) with either diplegic or quadriplegic cerebral palsy (CP). Muscle biopsies from the vastus laeralis muscle were obtained for biomedical and histological analysis during orthopaedic surgery as part of the child's ongoing care. Total collagen was quantified by hydroxyproline determination. Two clinical measures of severity, Modified Ashworth Scale and Balance, were shown to have a highly significant correlation with collagen content, and Ambulatory Status, Clonus, and Selective Muscle Control all showed positive trends. Collagen I accumulated in spastic muscle's endomysium which appeared to be thickened, and fibrotic regions with sparse muscle fibres were evident in more severe cases. This suggests that collagen may be involved in increases in muscle stiffness observed in spasticity. Once developed, these changes are essentially irreversible and we suggest that future treatments should consider including prevention of muscle fibrosis.

Femoral nailing for metastatic disease of the femur: a comparison of reamed and unreamed femoral nailing

A total of 73 consecutive intramedullary femoral nails were inserted for metastatic disease of the femur; 43 were reamed and 30 were solid nails. The two groups were similar with regards to age, type of primary tumour, anatomical site, acute or 'impending' fracture and postoperative survival. The 'solid' nail offers a satisfactory alternative form of stabilisation for metastatic disease of the femur with rates of implant failure which are comparable with the reamed nail. In this series bilateral nailing was not associated with any increase in mortality. Contrary to other reports, imposing a delay in patients with pain and a short life expectancy seems unjustified. The use of the 'solid' femoral nail does not prevent sudden death due to massive fat embolism.

Management of subtrochanteric fractures of the femur in children

We report the results of treatment in 99 children with subtrochanteric fractures of the femur. Late reviews of 60 of the 65 children treated with traction and then a hip spica after stabilization of the fracture by callus, and of 20 of the 22 treated with early closed reduction and a hip spica yielded 80% satisfactory outcomes. However, 27% of the fractures treated with early closed reduction required remanipulation. The satisfactory outcomes in the traction and delayed spica group would be increased to nearly 100% by using only skin traction, as persistent lengthening of the femur and pin-site pain, the main long-term complications, were the result of skeletal traction. Late review of 10 of the 12 children treated surgically showed 100% satisfactory medical outcomes but only 60% satisfactory patient-determined outcomes. Persistent pain in the thigh incision used for open reduction was the main cause of patient dissatisfaction.

Isolated fractures of the lesser trochanter in children

In a retrospective study of 1126 children with fractures of the proximal third of the femur, three children were found to have isolated fractures of the lesser trochanter. This fracture occurred from a fall in one child and following sporting activities, without a history of injury, in the others. In the latter children, the clinical presentations were similar to those of children with transient synovitis of the hip or Perthes disease. In each child, plain radiographs showed an avulsion fracture of the bony portion of the lesser trochanter. Early and complete recovery followed symptomatic treatment even when there was marked proximal displacement of the avulsed segment of the lesser trochanter.

Early detection of progression in adolescent idiopathic scoliosis by measurement of changes in back shape with the Integrated Shape Imaging System scanner

STUDY DESIGN

A retrospective study of 78 patients with right thoracic idiopathic scoliosis was done.

OBJECTIVES

To evaluate the reliability of the integrated Shape Imaging System scan (Oxford Metrics Ltd, Oxford, UK) in detecting progression of scoliosis and the use of back shape data in predicting scoliosis progression.

SUMMARY OF BACKGROUND DATA

At first presentation and every 3-6 months during the follow-up period, all patients underwent integrated Shape Imaging System scans and radiographic examinations, from which the Cobb angle was measured. The follow-up period was 18-49 months (mean = 31.4 months).

METHODS

Patients were divided into three groups according to the severity and progression of the Cobb angle. The spinal fusion, brace, and observation groups were compared using analysis of variance and the student's t test to detect significant differences among groups in the progression of deformity as measured by the integrated Shape Imaging System parameters and the Cobb angle.

RESULTS

Three of the Integrated Shape Imaging System parameters detected significant progression in the spinal fusion group 1 year earlier than the Cobb angle. Only one of the Integrated Shape Imaging System parameters detected a significant difference in progression between the brace and observation groups.

CONCLUSIONS

The Integrated Shape Imaging System technique demonstrated significant changes in this group of patients with progressive scoliosis. Serial measurements of back surface shape, particularly the size of the rib hump, may be predictive of progression. Serial Integrated Shape Imaging System scanning has advantages over serial radiography in the management of idiopathic scoliosis in addition to the avoidance of exposure to ionizing radiation.

Heel seats and shoe wear

Seventy-two children with excessive heel valgus and markedly uneven shoe wear were treated by Helfet heel seats for 18-36 months. Of the 52 children reviewed in this study, 44 had improved shoe wear. Simple heel seats offer economical treatment for children whose foot deformities destroy their shoes.

Quantifying the cosmetic defect of adolescent idiopathic scoliosis

Cosmesis is important in the treatment of adolescent idiopathic scoliosis patients. The aim of this study was to quantify the cosmetic defect using parameters of the ISIS (Oxford Metrics Ltd., Oxford, England) scan. Ten nonmedical judges scored photographs of 100 adolescent idiopathic scoliosis patients based on cosmetic criteria. This Cosmetic Spinal Score proved to be a reliable figure. The Cosmetic Spinal Score was then compared with ISIS parameters and the Cobb angle. An equation based on ISIS parameters was developed, which could predict Cosmetic Spinal Score with sufficient reproducibility to have a useful clinical application. Bracing reduced the rib hump but not enough to improve the cosmetic appearance. Spinal fusion and Harrington instrumentation improved all measured parameters influencing physical appearance.