Can Clinical Postpartum Muscle Assessment Help Predict the Severity of Postpartum Pelvic Girdle Pain? A Prospective Cohort Study

OBJECTIVE: The purpose of this study was to evaluate whether the clinical assessment of pelvic floor muscles and the diastasis recti abdominis could predict the severity of pelvic girdle pain during the first year postpartum. METHODS: Between 2018 and 2020, 504 women were recruited to this prospective longitudinal cohort study. At 2 to 3 months postpartum, their pelvic floor muscles and diastasis recti abdominis were assessed using vaginal palpation, observation, and caliper measurement. The participants completed the Pelvic Girdle Questionnaire (PGQ) at 2 to 3, 6, 9, and 12 months postpartum. Mixed-effect models were used to determine how the results of pelvic floor muscle and diastasis recti abdominis assessments predicted the PGQ score. A sub-analysis for middle to high PGQ scores was conducted. RESULTS: Maximal voluntary pelvic floor muscle contractions ≥3 (Modified Oxford Scale, scored from 0 to 5) predicted a decreased PGQ score (β = −3.13 [95% CI = −5.77 to −0.48]) at 2 to 3 months postpartum, with a higher prediction of a middle to high PGQ score (β = −6.39). Diastasis recti abdominis width did not have any significant correlation with the PGQ score. A sub-analysis showed that a diastasis recti abdominis width ≥35 mm predicted an increased PGQ score (β = 5.38 [95% CI = 1.21 to 9.55]) in women with pelvic girdle pain. CONCLUSION: The distinction between weak and strong maximal voluntary pelvic floor muscle contractions is an important clinical assessment in women with postpartum pelvic girdle pain. The exact diastasis recti abdominis width, measured in millimeters, showed no clinical relevance. However, a diastasis recti abdominis width ≥35 mm was associated with a higher PGQ score, and further research about this cutoff point in relation to pain is needed. IMPACT: This study highlights the importance of clinical assessment of pelvic floor muscles in patients with postpartum pelvic girdle pain. A better understanding of the role of this muscle group will enable more effective physical therapist treatment of pelvic girdle pain.