Introduction
Gluteal nerve consists of superior gluteal nerve and inferior gluteal nerve. Superior gluteal nerve, derives from L4 to S1, involves in hip abduction. Inferior gluteal nerve arising from L5 to S2, mainly innervates gluteus maximus and extends the hip. Both nerves are part of lumbosacral trunk and escapes pelvic cavity through greater sciatic foramen and runs under the pyriformis muscle. Gluteal nerve injury usually occurs at hip arthroplasty, which approach on the lateral or posterior side of the hip. On contrast, hysterectomy, which approach pelvic cavity anteriorly and rarely damages the gluteal nerve.
In this case report, the patient demonstrates weak right hip abduction and flexion after radial hysterectomy. The symptom was revealed as a result of gluteal nerve and femoral nerve injury. This unusual case of gluteal nerve injury after hysterectomy was diagnosed by electromyogram (EMG).
Case Report
The 66-year-old female patient complained of right thigh and buttock pain with motor weakness of the proximal part of right leg after hysterectomy. She was diagnosed as cervical cancer and underwent the radical hysterectomy with bilateral salpingo-oophorectomy with bilateral pelvic lymphadenectomy and paraaortic lymph node dissection.
After surgery, she exhibited gait abnormality with motor weakness of her right lower extremity:right hip flexor and abductor were poor (P) grade on manual muscle test (MMT). Excessive right hip external rotation was noted at swing phase of gait (Fig. 1.).
To diagnose the cause of her motor weakness, EMG was done at the Department of Rehabilitation 43 days after the surgery (Table 1.). The needle EMG performed on right gluteus medius and maximus, tensor fascia lata and iliacus muscle revealed increased insertional activity and some abnormal fibrillations (Fibs) and positive sharp waves (PSWs) at rest and reduced recruitment of motor units on volition and decreased interference on full volition. Hence, right superior and inferior gluteal nerve lesions with right femoral nerve injury were diagnosed. On follow-up examination 81 days after the surgery, she showed improvement of muscle strength:right adductor and hip flexor were fair (F) grade on MMT compared to P grade at first. Follow-up EMG done on the same day showed improvement of gluteal nerve injury:interference improved from 25% to 75% and normalized spontaeous activity and recruitment ratio were noted (Table 2.).
Discussion
Nerve injury during hysterectomy may occur by malpositioning of retractor, prolonged lithotomy position and by surgical incision. Since neuropathy after hysterectomy has low prevalence, it is difficult to diagnose motor weakness or pain after the surgery. Therefore, surgeons should keep in mind that any nerve injury during pelvic cavity operation is possible and it can be prevented by correct positioning and nerve-sparing surgical technique. |
