Morphometric analysis of the sacroiliac joint

Area of Science:

• Radiology
• Anatomy
• Orthopedics

Background:

• The sacroiliac (SI) joint connects the sacrum and innominate bones.
• Degenerative or inflammatory changes in the SI joint can cause lower back pain.
• Limited data exists on the morphometric characteristics of the SI joint.

Purpose of the Study:

• To measure the articular width of the SI joint.
• To define normal SI joint size in relation to age and sex.

Main Methods:

• 198 anteroposterior abdominal X-rays from 112 males and 86 females (age 17-91) were analyzed.
• SI joint articular space (anterior portion) was measured at medium and inferior levels using a computerized system.
• Data was analyzed using variance analysis, stratified by age groups.

Main Results:

• No significant sex-based differences in SI joint articular space width were found.
• A trend of diminishing SI joint articular space width with increasing age was observed.
• The anterior articular space was more easily measured than the posterior.

Conclusions:

• SI joint articular space width decreases with age.
• Age, not sex, is a primary factor influencing SI joint morphometry.
• Further research may clarify the clinical significance of age-related SI joint changes.