Groin Pain- Distance Running

Abstract

HISTORY: A 41-year-old ultra-distance runner developed progressive aching pain deep in the right groin with running over a 1-month period. The pain would gradually worsen with longer distance runs. He was running his usual 70 miles per week at the time of pain onset. He has completed multiple 100-mile runs throughout the last 10 years without prior injuries. PHYSICAL EXAMINATION: Examination revealed a slightly antalgic gait with reduced step length on the right, normal and symmetric lower extremity ROM, leg length, strength, and sensation. He had tenderness near the right pubic ramus and ischial tuberosity. DIFFERENTIAL DIAGNOSIS: 1. Tendinopathy of adductors or proximal hamstring. 2. Bone stress reaction or fracture of pubic ramus. 3. Intra-articular hip pathology. TESTS AND RESULTS: Right hip anterior-posterior and lateral x-ray: -Faint linear sclerosis and cortical irregularity at the right inferior pubic ramus Pelvis MRI: -Low signal intensity fracture line through the right inferior pubic ramus, with associated bone marrow edema -No evidence of labral or tendon pathology. DEXA Scan: -Lowest z-score= -1.9 standard deviations in the right femoral neck consistent with low bone mass. Laboratory and historical work-up for secondary causes of low bone mass revealed: -Vitamin D deficiency and low-normal testosterone levels -Vegan diet for the last year -History of childhood asthma and several courses of steroids for exacerbations in childhood -History of SSRI use for depression FINAL/WORKING DIAGNOSIS: Grade 4 fatigue fracture of the right inferior pubic ramus in setting of multi-factorial low bone mass in an ultra-distance male runner. TREATMENT AND OUTCOMES 1. Crutches for 12 weeks, based on symptoms. Recumbent bike or swimming to maintain fitness. 2. Supplemented Calcium (1500mg/day) and Vitamin D (ergocalciferol 50000 units weekly) 3. Liberalized diet to include meat and dairy. 4. He replaced his SSRI with buproprion for depression. 5. Repeat x-ray at 12 weeks showed increasing sclerosis indicative of early bony healing. 6. Tenderness nearly resolved by 12 weeks. 7. Anticipate initiation of ROM and non-impact loading exercise at 15 weeks. 8. Incremental return to running by 24 weeks, expecting normal strength, ROM, improved bone density and painless running by that time.