HISTORY: A 41-year-old female presented with new left pelvic and left ischial tuberosity pain after recreational distance running. Pain was localized to the left groin and described as “aching” without radiation or numbness. The patient, a former collegiate 800m track athlete, was diagnosed with left athletic pubalgia two years prior and managed conservatively with return to full pain-free running one year prior to consult. She was running 40 miles per week, ranging from 5-15 miles per day and had recently transitioned running shoe models 2-3 weeks prior. Pain had progressively increased to inability to tolerate running. PHYSICAL EXAMINATION: Examination revealed a symmetric, non-antalgic walk, equal leg lengths and ability to perform full squat. Resisted left hamstring flexion in the supine position with knees at 90 degrees reproduced left ischial tuberosity pain. Left hamstring tendon was palpable and intact. Range of motion was full throughout the bilateral lower extremities. Strength, reflexes, sensation and pulses were normal throughout. DIFFERENTIAL DIAGNOSIS: 1. Hamstring tendinosis 2. Pelvic stress fracture 3. Pelvic floor injury TESTS AND RESULTS: Anterior-posterior pelvis x-ray with two oblique views and lateral view: — Healing, non-displaced, periosteal reaction at the inferior ramus of the left pubic bone consistent with stress fracture not demonstrated on previous AP pelvis done one year prior. FINAL/WORKING DIAGNOSIS: Left inferior pubic ramus stress fracture TREATMENT AND OUTCOMES: 1. Immediate cessation of land-based running with pool running as tolerated for 2 months. 2. Initiated 800 IU Vitamin D and 2000 mg Calcium supplementation. 3. DEXA scan performed and negative for osteopenia. Subsequent Vitamin D level within normal limits. 4. 3 months from initial consult, patient tolerated treadmill evaluation and commenced a walk-to-run protocol with initiation of physical therapy. 5. Repeat AP pelvis x-ray demonstrated healed undisplaced fracture of left inferior pubic rami with solid bone union. Further imaging with MRI was not needed. 6. After 4 months, she tolerated land-based running without pain. Gait analysis was performed to ensure proper running mechanics with increased running frequency and duration in the prescribed walk-to-run protocol.