Cartilage hair hypoplasia: characteristics and orthopaedic manifestations.

PURPOSE: Cartilage hair hypoplasia (CHH) is a rare metaphyseal chondrodysplasia characterized by short stature and short limbs, found primarily in Amish and Finnish populations. Cartilage hair hypoplasia is caused by mutations in the RMRP gene located on chromosome 9p13.3. The disorder has several characteristic orthopaedic manifestations, including joint laxity, limited elbow extension, ankle varus, and genu varum. Immunodeficiency is of concern in most cases. Although patients exhibit orthopaedic problems, the orthopaedic literature on CHH patients is scant at best. The objective of this study was to characterize the orthopaedic manifestations of CHH based on the authors' unique access to the largest collection of CHH patients ever reported. METHODS: The authors examined charts and/or radiographs in 135 cases of CHH. We analyzed the orthopaedic manifestations to better characterize and further understand the orthopaedic surgeon's role in this disorder. In addition to describing the clinical characteristics, we report on our surgical experience in caring for CHH patients. RESULTS: Genu varum, with or without knee pain, is the most common reason a patient with CHH will seek orthopaedic consultation. Of the cases reviewed, 32 patients had undergone surgery, most commonly to correct genu varum. CONCLUSION: This paper characterizes the orthopaedic manifestations of CHH. Characterizing this condition in the orthopaedic literature will likely assist orthopaedic surgeons in establishing a correct diagnosis and appreciating the orthopaedic manifestations. It is important that the accompanying medical conditions are appreciated and evaluated.

Management of the rigid cavus foot in children and adolescents.

This article reviews historical approaches to the various osteotomies in the treatment of rigid cavus feet in children, with an emphasis on the biplanar nature of historical osteotomies. The Akron dome midfoot osteotomy is performed at the apex of the rigid cavus deformity and allows for maximum correction in any plane, and for varus, valgus, dorsal, plantar, and rotational correction. In that regard, the Akron dome midfoot osteotomy provides the greatest amount of multiplanar correction. It does not, however, provide correction of hindfoot deformities or deformity distal to the neck of the metatarsal.

Orthopaedic manifestations of chondroectodermal dysplasia: the Ellis-van Creveld syndrome.

BACKGROUND: Ellis-van Creveld is a dwarfing syndrome transmitted as an autosomal recessive trait. The constant features of the condition include acromelic-micromelic dwarfism, ectodermal dysplasia involving the nails, teeth and gums, postaxial polydactyly of the hands and congenital heart disease. Congenital heart disease affects 50-60 % of all patients and nearly 50 % of patients die by 18 months of age from cardiopulmonary complications. This study is intended to characterise the orthopaedic manifestations of Ellis-van Creveld based on the authors' unique opportunity to interview and examine the largest group of patients to date in the literature. METHODS: Detailed interviews, physical examinations and/or radiographs were available on 71 cases of Ellis-van Creveld syndrome. Data were collected from physical examinations, radiographs, computed tomography (CT) reconstruction and magnetic resonance imaging (MRI) of the knee. Pathoanatomy of the knee was reinforced by the direct surgical observation of 25 limbs surgically managed during adolescence and puberty. RESULTS: A number of interesting clinical and radiographic abnormalities were noted in the upper extremities and lower extremities, but by far the most significant orthopaedic finding was a severe and relentlessly progressive valgus deformity of the knee. Although many patients had difficulties making a "fist" with the hand, no patient reported any functional disability. The severe valgus deformity of the knee is the result of a combination of profound contractures of the iliotibial band, lateral quadriceps, lateral hamstrings and lateral collateral ligament, leading to lateral patellar subluxation and dislocation. The lateral portion of the upper tibial plateau presents with cupping and progressive depression of the lateral plateau, along with severe valgus angulation of the proximal tibia and fibula. A proximal medial tibial exostosis is seen in nearly all cases. CONCLUSION: This is the largest group of Ellis-van Creveld syndrome patients identified in the literature. An understanding of the orthopaedic pathoanatomy of the knee deformity is critical to determining the appropriate surgical management. This paper characterises the orthopaedic manifestations of Ellis-van Creveld syndrome and especially identifies the pathoanatomy of the severe and progressive valgus knee deformity. LEVEL OF EVIDENCE: Level II.

Fracture incidence following plate removal in Legg-Calvé-Perthes disease: a 32-year study.

PURPOSE: The decision of whether or not to remove pediatric metallic implants remains a controversial issue. Many factors have been cited both in favor and against routine removal of metallic implants. The purpose of this study was to determine the fracture rate following the routine removal of hardware from patients with Legg-Calvé-Perthes (LCP) disease treated by proximal femoral varus osteotomy (PFVO) and to determine if there is an optimal time to remove hardware in this population. METHODS: We performed a retrospective chart review of children who had PFVO with subsequent hardware removal from March 1973 to May 2005 performed by a single surgeon. A total of 196 hips in 184 patients were included. Data was analyzed using logistic regression. Inverse prediction was also used to obtain estimates of the time needed to produce probabilities of no fracture. RESULTS: Ten out of the 196 hips included (5.1%) sustained a fracture after plate removal. The time from osteotomy to plate removal averaged 10.4 months in the nonfracture group and 4.8 months in the fracture group. This was statistically significant (P < 0.0001). Using the logistic regression model, the predicted time to plate removal corresponding to a 95% probability of no fracture was between 5.1 and 8.4 months. CONCLUSIONS: Plate removal remains a reasonable choice but questions remain as to the timing of removal. These data suggest that patients may benefit from extending the time to hardware removal beyond radiographic union to at least six months or more after the osteotomy.