Buttock Pain - Cross Country Skier

Abstract

HISTORY: A 32 year old male cross country skier presented with a multi-year history of right posterior “deep” buttock pain. He endorsed associated radiation down his posterior right thigh, leg and into the plantar foot. He described “burning” and “tingling” that increased with prolonged sitting and standing. Surgical history was significant for bilateral hip arthroscopic surgeries for femoral acetabular impingement. He denied any significant weakness or change in bowel/bladder function. PHYSICAL EXAMINATION: Exam revealed right toe flexor weakness. Straight leg raise reproduced his right lower limb and buttock pain. Reflexes were physiologic and symmetric. Hip range of motion was full and pain free. Intraarticular provocative maneuvers were negative. He had tenderness to palpation of his deep hip external rotators. FABER’s test and passive piriformis stretch reproduced his right buttock and lower limb symptoms. DIFFERENTIAL DIAGNOSIS: S1 Radiculopathy Sacroiliac Joint Dysfunction Piriformis Syndrome Hip Osteoarthritis Proximal Hamstrings Tendinopathy Ischiofemoral Impingement Syndrome TEST AND RESULTS: Lumbar spine x-rays showed anterolisthesis of L5 on S1 with associated disc space narrowing and MRI showed paracentral disc protrusion at L5-S1 effacing the right S1 nerve root. Electromyogram showed evidence of a chronic, inactive right S1 radiculopathy. Ultrasound of the right hip identified a small nerve fascicle, separate from the sciatic nerve, appearing to pierce the piriformis muscle. MRI of the pelvis with lumbosacral plexus protocol demonstrated the sciatic nerve coursing deep to the right piriformis muscle and identified the right S2 nerve root coursing through the piriformis muscle. FINAL WORKING DIAGNOSIS: Piriformis syndrome resulting in active, compressive, right S2 neuritis Superimposed, chronic, inactive right S1 radiculopathy TREATMENT AND OUTCOMES: Extensive PT with plateau in improvement. No relief with right S1 selective nerve root block. Ultrasound guided piriformis corticosteroid injection provided temporary relief of buttock pain. Ultrasound guided sciatic nerve hydrodissection coupled with neural flossing provided several months of relief and allowed the patient to return to cross country skiing. Surgical referral for consideration of piriformis release.