Click here to view next page of this article
LCPD is idiopathic osteonecrosis or avascular necrosis of the CFE, and the associated complications thereof, occurring in an immature, growing child. This osteochondrosis is caused by an interruption of the CFE blood supply. It is primarily a disorder affecting males (4-5:1) and is bilateral in approximately 20% of children. Children with LCPD also often have delayed bone ages, disproportionate growth, and Legg-Calve-Perthes disease.
The clinical onset of LCPD typically is between the ages of 2 and 12 yr (mean, 7 yr). Most children present with mild or intermittent pain in the anterior thigh and a limp. The classic presentation has been described as a "painless limp." The pertinent early
Anteroposterior and Lauenstein (frog) lateral radiographs of the pelvis should be obtained to establish the diagnosis. The radiographic characteristics can be divided into five distinct stages representing a continuum of the disease process: (1) cessation of CFE growth, (2) subchondral fracture, (3) resorption (fragmentation), (4) reossification, and (5) healed or residual Legg-Calve-Perthes disease.
There are three radiographic classification systems of the extent of CFE involvement. Catterall developed a four-group classification on the basis of the appearance of the CFE at maximum resorption. Although this classification has been helpful in retrospective analysis.
The short-term prognosis relates to the femoral head deformity at the completion of the healing stage. Adverse risk factors include older age at clinical onset, extensive CFE involvement, femoral head containment, reduced range of hip motion, and premature growth.
Two radiographic techniques evaluate the sphericity of the femoral head at the completion of the disease process, which correlates with the risk for degenerative osteoarthritis as an adult. In the Mose circle criteria, a transparent template with concentric circles is placed over the anteroposterior and Lauenstein lateral radiographs. If the variation of sphericity of the femoral head in the two views is 0-2.
LCPD is a local, self-healing disorder. Prevention of femoral head deformity and secondary osteoarthritis are the only justifications for treatment. The treatment goals are (1) elimination of hip irritability, (2) restoration and maintenance of a good range.
Expectant observation is appropriate for all children younger than 6 yr at clinical onset regardless of the extent of CFE involvement.
Nonsurgical or surgical containment of the femoral head in the course of the disease is indicated when (1) the age at clinical onset.
Abduction casts (Petrie) or orthoses are commonly used to contain the femoral head within the acetabulum. Containment is continued only until there is early radiographic subchondral reossification. Because this usually occurs 12-17 mo after.
The selection of pelvic or femoral osteotomy for surgical containment is based on the philosophy and technical expertise.
If significant femoral head deformity prevents reduction of the femoral head into the acetabulum.