The Association of Variations in Hip and Pelvic Geometry With Pregnancy-Related Sacroiliac Joint Pain Based on a Longitudinal Analysis

Abstract

Study Design. 

Cross-sectional study using radiological measurements and longitudinal data analysis.

Objective. 

We aim to explore hip/pelvic geometry on anteroposterior radiographs and examine if such parameters are associated with clinical symptoms.

Summary of Background Data. 

Pregnancy-related sacroiliac joint pain is a common disease and is responsible to the disability of daily activities. The etiology is likely to be correlated with the biomechanical factors which are determined by trunk load and hip/pelvic geometry. Previous studies have already found the association between symptoms and weight increase during pregnancy. However, the relationship between bony anatomy and pregnancy-related sacroiliac joint pain remains unknown.

Methods. 

In total, 72 women were included in the final analysis. In pregnant women with self-reported sacroiliac joint pain, pain scores at 12, 24, 30, and 36 weeks of pregnancy were recorded and included in a mixed-effect linear regression model as dependent variables. The radiological measurements were included as independent variables. Furthermore, to investigate the relationship between hip/pelvic geometry and the activity-specific nociceptive phenomenon, the radiological measurements between patients with and without activity-induced pain were compared using a binominal logistic regression model.

Results. 

The relative bilateral is chial tuberosity distance (betta coefficient: 0.078; P = 0.015) and the relative bilateral femoral head length (betta coefficient: 0.011; P = 0.028) showed significant interactions with the slope of pain scores. Moreover, women whose pain exacerbate during prolonged walking had a higher odds in hip/pelvic geometry of the bilateral ischial tuberosity distance (odds ratio [OR]: 1.12; P = 0.050) and the bilateral femoral head length (OR: 1.16; P = 0.076) with approximately significant P-value.

Conclusion. 

These data indicate hip/pelvic anatomical variations are associated with the degree of pain increasing and the activity-specific pain during pregnancy, which may help to have further understanding on the biomechanical factor in developing pregnancy-related sacroiliac joint pain.

Level of Evidence: 3

In Brief

The current study determined that variations of hip and pelvic anatomy among women can be associated with different degrees of both generalized, and activity-specific, sacroiliac joint pains that are often experienced during pregnancy.