Background: Coccidioidomycosis is an invasive fungal infection caused by the inhalation of aerosolized spores of Coccidioides spp., which reside in the arid soil of the southwestern United States and northern Mexico. Approximately two thirds of cases are asymptomatic, and the remainder usually present with mild flu-like symptoms. Dissemination of coccidioidomycosis is rare, and can lead to extrapulmonic diseases including meningitis, osteomyelitis, and skin and soft-tissue involvement. The purpose of this study is to report our experience with musculoskeletal coccidioidomycosis in children. Methods: This was a retrospective chart review of patients with musculoskeletal infection with Coccidioides spp. at a tertiary care pediatric hospital from 1997 to 2010, identified by a search of ICD-9 codes and hospital diagnoses. Demographic and clinical data were collected from medical records, including the age of the patient, sex, white blood cell count, immunocompetence, length of stay, location of involvement, and initial treatment. In total, 20 children were identified with musculoskeletal coccidioidomycosis. The mean age was 12.3 years (range, 2 to 17 y) at time of diagnosis. Diagnostic criteria included positive imaging tests (plain film+MRI), serologic positive titers, and/or biopsy with positive cultures. Results: The most common presenting symptom was bone pain (100%); only 3 (15%) patients had accompanying signs/symptoms of pulmonary infection. Only 2 (5%) patients had a white blood cell count >15×10⁹/L (5%). Locations of infection included the foot (28%), knee (14%), spine (12%), forearm (10%), lower leg (6%), and other sites (30%). Fluconazole was the most common antifungal agent used (75%). Surgical intervention was required in 10 (50%) patients. Conclusions: This is the first series that has described musculoskeletal coccidioidomycosis exclusively in children. This study suggests that the initial presentation of this disease can be nonspecific and difficult to recognize in children. Clinicians should consider this diagnosis when faced with a musculoskeletal infection in children from the southwestern United States and northern Mexico. Level of Evidence: IV (case series).

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.