Stressed Out: Recurrent Leg Pain And Fatigue In A Collegiate Male Long-distance Runner

HISTORY: A 23 YO male cross-country runner with history of 4 prior stress fractures and vitamin D deficiency (currently on 5000 IU daily) presented Jan 2023 with L thigh pain after a 16-mile run; suspicious for a stress fracture. Running 85 miles a week. ROS: positive for fatigue, low libido and erectile dysfunction. Nutrition history: calorie intake around 1800-2000 kcals/day. Sleeps 9 hrs/night. PHYSICAL EXAM: Ht 6’1”, Wt 135 lbs, BMI 18.3. Skin with subtle yellowing, no frank jaundice; no scleral icterus. No signs of thyromegaly. No lymphadenopathy. No HSM, dentition normal. MSK exam normal. DIFFERENTIAL DIAGNOSIS: 1) Femoral Stress Fracture 2) Femoral Acetabular Impingement 3) Male Athlete Triad/Relative Energy Deficiency in Sport (RED-S) 4) Metabolic disease 5) Low T syndrome TESTS AND RESULTS: -TSH 1/17/23: 1.89 (0.3-4) -Free T4 1/17/23: 1.09 (0.9-1.7) -Free Testosterone 1/17/23: 1.51 (5.25-20.7) -Total Testosterone 1/17/23: 77 (240-950) -Vitamin D 1/17/23: 63 (12-99) -Ferritin 1/17/23: 40 (20-300) -L femur/hip x-ray 1/12/23: negative for fractures -L femur/hip MRI 1/14/23: periosteal edema along the medial proximal femoral diaphysis c/w stress reaction. CAM deformity at femoral head/neck junction. -DEXA scan 1/30/23: T score of -1.9 at L-spine and -0.1 at femoral neck FINAL DIAGNOSIS: Male Athlete Triad/Relative Energy Deficiency in Sport (RED-S) TREATMENT AND OUTCOMES: 1) Increased caloric intake to 2500-2600 daily over 6 weeks. 2) Return to run weeks 6-12. 3) Follow-up at 6 and 12 weeks demonstrated improvements in fatigue and erectile dysfunction, 3 lb weight gain. Repeat labs: Free and Total Testosterone 118 (90-300) & 379 (240-950). 4) Left groin pain reoccurred 4 months later. Reported calories back down to <2300 daily. Testosterone, Vitamin D, and iron levels wnml. L hip MRI showed small labral tear with CAM deformity and interval resolution of femoral stress reaction. PT referral given and patient declined USG CSI or diagnostic lidocaine. RTR 2 months later was successful. 5) Presented 10/2023 for new R thigh pain. R femur MRI 2 weeks later showed R femoral stress reaction of lesser trochanter and iliopsoas strain. Reported calories at 2000/day since not running. 6) Back on nutrition ramp up and counseling. Repeat labs and DEXA pending. Missed prior endo appt, but rescheduled. Close follow-up planned.