Guided Growth of the Proximal Femur for the Management of the 'Hip at Risk' in Children with Cerebral Palsy-A Systematic Review

Hip displacement in children with cerebral palsy: surveillance to surgery - a current concepts review

This review brings together a multidisciplinary, multinational team of experts to discuss the current state of knowledge in the detection and treatment of hip displacement in cerebral palsy (CP), a global public health problem with a high disease burden. Though common themes are pervasive, different views are also represented, reflecting the confluence of traditional thinking regarding the aetiology and treatment of hip displacement in CP with emerging research that challenges these tried-and-true principles. The development of hip displacement is most closely related to gross motor function, with radiographic surveillance programs based on the Gross Motor Function Classification System (GMFCS), the goal being early detection and timely treatment. These treatments may include non-operative methods such as abduction bracing and Botulinum Neurotoxin A (BoNT-A), but outcomes research in this area has been variable in quality. This has contributed to conflicting opinions and limited consensus. Soft tissue lengthening of the hip adductors and flexors has traditionally been employed for younger patients, but population-based studies have shown decreased survivorship for this treatment when performed in isolation. Concerns with the identification of hip displacement in very young children are raised, noting that early reconstructive surgery has a high recurrence rate. This has prompted consideration of viable minimally invasive alternatives that may have better success rates in very young children with CP, or may at least delay the need for osteotomies. Recent reports have implicated the role of abnormal proximal femoral growth and secondary acetabular dysplasia as a primary cause of hip displacement, related to ambulatory status and abductor function. As such, guided growth of the proximal femur has emerged as a possible treatment that addresses this purported aetiology, with promising early results.

The Etiology of Neuromuscular Hip Dysplasia and Implications for Management: A Narrative Review

This study summarizes the current knowledge of the etiology of hip dysplasia in children with neuromuscular disease and the implications for management. This article is based on a review of development of the hip joint from embryology through childhood growth. This knowledge is then applied to selective case reviews to show how the understanding of these developmental principles can be used to plan specific treatments. The development of the hip joint is controlled by genetic shape determination, but the final adult shape is heavily dependent on the mechanical environment experienced by the hip joint during growth and development. Children with neuromuscular conditions show a high incidence of coxa valga, hip dysplasia, and subluxation. The etiology of hip pathology is influenced by factors including functional status, muscular tone, motor control, child's age, and muscle strength. These factors in combination influence the development of high neck-shaft angle and acetabular dysplasia in many children. The hip joint reaction force (HJRF) direction and magnitude determine the location of the femoral head in the acetabulum, the acetabular development, and the shape of the femoral neck. The full range of motion is required to develop a round femoral head. Persistent abnormal direction and/or magnitude of HJRF related to the muscular tone can lead to a deformed femoral head and a dysplastic acetabulum. Predominating thigh position is the primary cause defining the direction of the HJRF, leading to subluxation in nonambulatory children. The magnitude and direction of the HJRF determine the acetabular shape. The age of the child when these pathomechanics occur acts as a factor increasing the risk of hip subluxation. Understanding the risk factors leading to hip pathology can help to define principles for the management of neurologic hip impairment. The type of neurologic impairment as defined by functional severity assessed by Gross Motor Function Classification System and muscle tone can help to predict the risk of hip joint deformity. A good understanding of the biomechanical mechanisms can be valuable for treatment planning.

Hip Surveillance and Management of Hip Displacement in Children with Cerebral Palsy: Clinical and Ethical Dilemmas

Hip displacement is the second most common musculoskeletal deformity in children with cerebral palsy. Hip surveillance programs have been implemented in many countries to detect hip displacement early when it is usually asymptomatic. The aim of hip surveillance is to monitor hip development to offer management options to slow or reverse hip displacement, and to provide the best opportunity for good hip health at skeletal maturity. The long-term goal is to avoid the sequelae of late hip dislocation which may include pain, fixed deformity, loss of function and impaired quality of life. The focus of this review is on areas of disagreement, areas where evidence is lacking, ethical dilemmas and areas for future research. There is already broad agreement on how to conduct hip surveillance, using a combination of standardised physical examination measures and radiographic examination of the hips. The frequency is dictated by the risk of hip displacement according to the child's ambulatory status. Management of both early and late hip displacement is more controversial and the evidence base in key areas is relatively weak. In this review, we summarise the recent literature on hip surveillance and highlight the management dilemmas and controversies. Better understanding of the causes of hip displacement may lead to interventions which target the pathophysiology of hip displacement and the pathological anatomy of the hip in children with cerebral palsy. We have identified the need for more effective and integrated management from early childhood to skeletal maturity. Areas for future research are highlighted and a range of ethical and management dilemmas are discussed.