[Reference values for development of the iliac crest apophysis (Risser sign)]

Area of Science:

• Orthopedics
• Radiology
• Pediatric Spine Deformity

Background:

• Idiopathic scoliosis assessment relies on skeletal maturity indicators.
• The Risser staging system, based on iliac apophysis maturation, is crucial for treatment planning.
• Existing Risser stage standards may not reflect current population trends in skeletal maturation.

Purpose of the Study:

• To update standard values for Risser staging of iliac bone apophysis maturation.
• To provide current data for assessing skeletal maturity in idiopathic scoliosis.
• To investigate sex-based differences in maturation timing.

Main Methods:

• Retrospective analysis of 515 X-rays from 154 German descent patients with idiopathic scoliosis (ages 10-20).
• Calculation of mean chronological age, standard deviation, and t-values for each Risser stage.
• Comparison of maturation data between female and male patients.

Main Results:

• Significant differences in mean chronological age were observed across Risser stages.
• Skeletal maturation, indicated by ossification timing, begins earlier and concludes later than previously established.
• Standard values for Risser staging differ significantly between female and male patients.

Conclusions:

• Accelerated skeletal maturation necessitates updated standard values for Risser staging.
• Current Risser stage standards require revision due to observed maturation changes.
• The study provides current data for skeletal maturation assessment in idiopathic scoliosis.