(Kiosk 5) Postherpetic Lumbar Radiculopathy: A Case Report

Case Diagnosis: A 57-year-old female presents with left lower extremity pain due to postherpetic radiculopathy.

Case Description or Program Description: A 57-year-old female, with a recent history of herpes zoster infection (HZV) causing vesicular lesions on left anterior thigh and calf. Skin lesions resolved after course of valacyclovir. Subsequently developed left hip and groin pain with radiation down her anterior thigh to her knee. Pain described as sharp with a pulsatile quality, 9/10 on NRS, worse with sitting, sleeping, palpation and with bowel movements, no palliative factors. She endorsed mild left lower extremity weakness, denied bowel/bladder incontinence or saddle-anesthesia.

Setting: Outpatient Spine Clinic

Assessment/Results: Physical exam showed markings indicative of healed zoster lesions along the left anterior thigh, without evidence of active zoster lesions. Mild tenderness over left gluteal muscles. Full active and passive hip ROM. Grade 4+/5 strength in left hip flexors and abductors, grade 5/5 left knee extension and left hip adduction. Decreased sensation over left lateral thigh. Normal bilateral lower extremity DTRs. Lumbar spine MRI showed moderate degenerative disc disease at L4-L5 without significant central or neuroforaminal stenosis. Electrodiagnostic studies done 2 months after HZV, showed evidence of a left L3/L4 lumbar radiculopathy. The patient was subsequently diagnosed with postherpetic lumbar radiculopathy and Lyrica was initiated, she experienced full resolution of symptoms five months later.

Discussion (relevance): Initially believed to be rare, herpes zoster radiculopathy has been reported to occur in 5-30% of HZV cases. It more commonly affects upper extremities than lower extremities. Weakness can develop 2-3 weeks after the onset of skin lesions. The prognosis of herpes zoster related radiculopathy/paresis is good, with improvement occurring within 6-12 months.

Conclusions: Obtaining a detailed history including recent infections and skin changes are important questions in developing a thorough differential for pain. This information in conjunction with electrodiagnostic studies and advanced imaging can help differentiate postherpetic radiculopathy from other pathologies.