591 DIFFERENTIAL DIAGNOSIS: 1.Labral Tear 2.Soft Tissue injury: Rectus femoris, psoas, adductor or tear/avulsion 3.Stress fracture of the Femoral neck 4.Slipped upper femoral epiphysis/ Perthes TEST AND RESULTS: Magnetic Resonance Imaging: Extensive bone marrow oedema involving the left superior pubic ramus extending proximally to border the triradiate cartilage. Computed Tomography: Images are consistent with recurrent trauma to triradiate cartilage and pubis. FINAL WORKING DIAGNOSIS: Minimally displaced fracture of the tri-radiate cartilage TREATMENT AND OUTCOMES: Conservative management for further 6 weeks. With repeat re-assessment for gradual weight-bearing program and MRI imaging. Return to full play at six months. 2233 May 29, 10:10 AM - 10:30 AM Foot Pain in an Adolescent Runner Ashley D. Zapf 1 , Terry Nicola, FACSM 2 . 1 Schwab Rehabilitation Hospital, Chicago, IL. 2 University of Illinois at Chicago, Chicago, IL. (Sponsor: Dr. Terry Nicola, FACSM) (No relationships reported) HISTORY: A 16 year old cross country runner averaging 42 miles per week began to experience pain in the dorsal medial aspect of his left foot one day while running. The patient informed his athletic trainer who recommended rest and wearing a walking boot on the left foot for 1 week. After 1 week, the pain had completely resolved, and the patient was allowed to resume running. The patient remained pain free for 2 weeks, however, his dorsal medial left foot pain resurfaced. He resumed rest and wearing the walking boot, and sought further evaluation at the Sports Medicine clinic. PHYSICAL EXAM: Examination in clinic revealed no tenderness to palpation of the feet bilaterally. No deformity, erythema, edema, ecchymoses was noted along the lower extremities or in the feet bilaterally. Pt had 5/5 strength with dorsiflexion, plantarflexion, inversion, eversion bilaterally. Pes Planus noted bilaterally. DIFFERENTIAL DIAGNOSIS: -Navicular Stress Fracture -Metatarsal Stress Fracture -Posterior Tibial Enthesopathy -Shoe Midfoot Entrapment TEST AND RESULTS: -Xray Left Foot: Negative for fracture. -MRI Left Foot: Nondisplaced incomplete stress fracture of the base of the 1st metatarsal. Marked edema and T1 hypodensity of all 5 distal phalanges, and the second and third middle phalanges. -DEXA Scan: Lowest measured Z-Score is AP Spine L1-L4 with Z-Score -1.8. -Vitamin D Level: 22.8. FINAL/WORKING DIAGNOSIS: 1st Metatarsal Stress Fracture likely secondary to previously undiagnosed Idiopathic Juvenile Osteopenia TREATMENT AND OUTCOMES: 1. Ambulation with the walking boot for 6 weeks. Bicycling for 30 min per day while wearing the boot allowed, but no running or jumping activities. 2. Referral to Family Physician and Endocrinologist, and Vitamin D supplementation started. Follow-up Vitamin D level in 3 months. 3. Repeat XRays of the left foot obtained after 6 weeks in the walking boot. XRays negative for fracture. 4. Walking boot discontinued 6 weeks post-injury. Physical therapy started with a focus on foot and ankle strengthening exercises. 5. Repeat MRI Left Foot 8 weeks post-injury showing healing 1st metatarsal stress fracture and stable abnormal marrow signal in the distal phalanges. 6. Walk to run program started 8 weeks post-injury with eventual full return to sport when pain-free running achieved. 2234 May 29, 10:30 AM - 10:50 AM Back pain - Adolescent Runner Mary E. Dubon 1 , Monica Rho 2 . 1 McGaw Medical Center of Northwestern University/Rehabilitation Institute of Chicago, Chicago, IL. 2 Rehabilitation Institute of Chicago, Chicago, IL. Reported Relationships: M.E. Dubon: Salary; Husband works on computer programming for Medstrat, an orthopedics PACS company. HISTORY: 17 year old female runner with anemia presented with right-sided low back pain that started 2 weeks prior to the initial visit in our clinic. She had been running 5 miles daily, averaging 25 miles weekly. She denied recent training or shoe changes. Her pain started about 2 miles into a run. She completed the run despite pain and had not been able to run since due to pain. The pain was very severe for 3 days, leading to difficulty walking. She described her pain as non-radiating, stabbing, stiff, and dull. She had no prior history of stress fractures. She reported a recent history of oligomenorrhea. She denied history of disordered eating. PHYSICAL EXAMINATION: Exam revealed mild pain with 90 degrees of lumbar flexion, painless lumbar extension, right posterior superior iliac spine tenderness to palpation, severe pain with right anterior posterior glide, painless right hip range of motion, and positive right Patrick’s test. Left Patrick’s test resulted in right posterior pelvic pain. DIFFERENTIAL DIAGNOSIS: 1. Female Athlete Triad with associated stress fracture 2. Sacral Stress Fracture 3. Sacroiliac Joint Dysfunction 4. Discogenic Low Back Pain 5. Spondylolysis TESTS AND RESULTS: 1. Pelvic Magnetic Resonance Imaging: Non-displaced stress fracture of the right half of the S1 vertebral body 2. Bone Density Scan: Z scores: Lumbar -2.7, Right Hip Femoral Neck -1.3, Left Hip Femoral Neck -1.4 3. Vitamin D Level: 35.5 FINAL WORKING DIAGNOSIS: Sacral Stress Fracture Female Athlete Triad TREATMENT AND OUTCOMES: 1. Partial weight-bearing with crutches for 3.5 weeks from diagnosis with progression to full weight bearing as patient became asymptomatic. 2. Physical therapy 3.5 weeks after diagnosis working on core strengthening, hip strengthening, and slow return to running program. 3. No running initially. Shin pain 7.5 weeks from diagnosis with slow return to running (ran 1 minute/walked 1 minute for 1 mile for 3 days then ran 2 minutes/walked 1 minute), so halted running until 11 weeks from diagnosis when reinitiated return to running starting with 1 minute running/1 minute walking.