The rib epiphysis and other growth centers as indicators of the end of spinal growth

Study Design. The association of capping and fusion of the iliac apophysis, and closure of the proximal humerus and rib epiphyseal growth plates to the end of spinal growth, was evaluated in a cohort of patients with juvenile and adolescent idiopathic scoliosis. Objectives. To determine the association of closure of the proximal rib epiphysis growth plate, the proximal humeral epiphyseal growth plate, and capping ( Risser 4), and fusion ( Risser 5) of the iliac apophysis to growth cessation in patients with idiopathic scoliosis. Summary of Background Data. Accurate evaluation of remaining spinal growth is the basis of decision- making in skeletally immature patients with scoliosis. The ossification of the iliac apophysis ( Risser sign) has been the main indicator used for making this determination. The accuracy of this sign has been called into question and may be supplemented with data from other growth centers. Methods. A total of 101 patients with juvenile or adolescent idiopathic scoliosis undergoing brace treatment were followed for a minimum of 2 years following termination of bracing. Serial height measurements and evaluation of iliac apophysis ossification, proximal humerus, and rib epiphysis growth center closure were performed for each patient. Results. The iliac apophysis capped ( Risser 4) at a mean age of 14.9 years for girls and 16.0 years in boys. Seventy- six of the 101 patients ( 75.2%) had further growth after Risser 4 status. The mean growth was 1.75 cm in the girls and 2.46 cm in the boys. No growth occurred after iliac apophysis fusion ( Risser 5) or closure of either the rib epiphysis or proximal humerus growth plates. Conclusions. Capping of the iliac apophysis is not the final indicator for the end of spinal growth. Other growth centers should be evaluated in conjunction with serial height measurements when making decisions on the management of the scoliosis patient.