Orthopedics - Oleksa A.P. 2006

Pathophysiology of Joints
Developmental Defects and Congenital Skeletal Anomalies
Osteoonychodysostosis (Nail-Patella Syndrome)

Osteonychodysostosis is an autosomal dominant inherited genetic disorder linked to the ABO Blood Groups. Family members with the same blood types, compared to those with different ones, have an increased risk of developing the disease. This disorder maps to the long arm of chromosome 9 (Campeau E., Watkins D., Rouleau G.A. et al., 1995). In the most severely affected patients, the condition manifests immediately after birth, but is often diagnosed belatedly. A family METABOLISM/13.html">History of the disorder may prompt an evaluation. Patients are typically examined on an outpatient basis despite the presence of orthopedic deformities. Clinically, the Nails are hypoplastic or absent. Many patients present with abnormal feet, ranging from flat feet to Clubfoot. Toenails are less affected than fingernails. Pelvic narrowing may also be detected radiographically in the anteroposterior projection (in 33 of 44 patients, according to Guidera K.J. et al., 1991; Sartoris D.J., Resnick D., 1987). Subluxation or dislocation of the Femur is rare. Dislocation or subluxation of the radial HEAD occurs more frequently, clinically manifested by restricted elbow flexion, reduced supination, or valgus deformity of the elbow. The Patella is abnormal in all patients due to hypoplasia, which manifests as varying degrees of dislocation. Valgus curvature of the knees with flexion contracture and other radiographic knee abnormalities are common. Spinal anomalies may also be present. Orthopedic Treatment is primarily aimed at improving FOOT and patellar function.