Sonographic finding of postpartum levator ani muscle injury correlates with pelvic floor clinical examination.

Objectives: Correlation of the sonographic finding of levator ani muscle (LAM) injuries with clinical examination in primiparous women following vaginal delivery has not been fully described. We aimed to examine the correlation of three-dimensional transperineal ultrasound (3D-TPS) finding of LAM defects with results of clinical examination of the pelvic floor, at intermediate follow-up.

Methods: Subjects were primiparae 3-21 months following vaginal delivery, who had not become pregnant or delivered in the interim. On 3D-TPS, LAM trauma was diagnosed when discontinuity and distortion were visible in the most anteromedial part of the pubovisceral muscle in the coronal C-plane or rendered image. Clinical examination was performed by a physiotherapist who was blinded to the ultrasound results, and included palpation of the medial and lateral parts of the LAM mass, evaluation of tissue quality and whether there was any palpable gap. Muscle strength was evaluated using the modified Oxford scale.

Results: Eighty-seven women were included, 19 (21.8%) of whom were found to have a sonographic LAM injury. Oxford score palpation parameter of asymmetric muscle mass or texture was significantly correlated with the finding of a LAM defect: of 68 women with normal 3D-TPS, 22 (32.4%) were found to have asymmetry of muscle mass or tissue quality on clinical examination vs 12 (63.2%) of 19 women with sonographic evidence of LAM injury (P = 0.016). Muscle strength and endurance parameters did not significantly correlate with the 3D-TPS findings.

Conclusion: Our findings suggest that persistent 3D-TPS LAM injury after primary vaginal delivery has clinical expression in changes in mass and texture of the LAM, as assessed by palpation.