Objective:

To characterize cases of peripartum sciatic nerve injury and highlight the importance of MR imaging in this setting.

Background:

Lower extremity nerve injury occurs in about 1% of vaginal deliveries and impacts quality of life and perception of future pregnancies. Data is limited regarding etiology and risk factors, and in individual cases the mechanism may remain unclear. MR neurography is frequently utilized in the evaluation of peripheral nerve injuries, but its use in peripartum nerve injury is not reported.

Design/Methods:

Five cases of peripartum sciatic neuropathy were evaluated longitudinally. Data was collected regarding demographics, pregnancy, delivery, risk factors, examination, and outcomes. All patients underwent MR neurography and most underwent EMG/NCS.

Results:

Patients were mostly nulliparous (n=4). All 5 received epidurals and attempted vaginal delivery,  and 1 delivered via C-section. Second (pushing) stage of labor lasted 5-240 minutes. All patients noted asymmetric sensorimotor symptoms, at times with onset prior to delivery (n=2) and with severe back pain (n=1). All patients were concerned about epidural complications. When performed, EMG/NCS supported sciatic neuropathy and other potential localizations (n=4). MR imaging identified sciatic neuropathy that was unilateral (n=4) or bilateral (n=1); abnormalities involving bilateral S1 roots (n=1), femoral nerve (n=1), and lumbosacral plexus (n=2); and variant sciatic nerve anatomy (n=2). Symptoms resolved as early as 3 weeks (n=1), but typically improved but persisted at 3 months (n=4). 

Conclusions:

Peripartum sciatic neuropathy can occur without typical risk factors and can occur bilaterally or in conjunction with other neuropathies. MR neurography provides useful guidance regarding precise localization and variant anatomy. This in turn informs discussions about mechanisms of injury, and potential practice changes that may help prevent such injuries.