Anterior Ankle Pain In A Female Recreational Runner

HISTORY: A 28-year-old female recreational runner presented for progressive right ankle pain for the past 3 weeks. She had been starting to train for her first upcoming half-marathon when she had to decrease her volume and intensity of training due to pain. Initially she had presented to urgent care where she was told she had an ankle sprain and to give it a few weeks and if not improved to follow up with orthopedics. Upon her presentation, she was unable to ambulate without antalgia due to the pain. PHYSICAL EXAMINATION: Examination revealed mild soft tissue swelling over anterior tibia with no ecchymosis or other skin abnormalities. There was tenderness to palpation over the distal anterior tibia and medial malleolus. Both passive and active range of motion was normal in the lower extremity. Strength was 5/5 in ankle dorsiflexion, plantarflexion, inversion, and eversion. Lower extremity sensation and circulation was intact. She was unable single leg hop without pain. DIFFERENTIAL DIAGNOSIS: 1. Medial tibial stress syndrome 2. Medial malleolus stress fracture 3. Posterior tibialis tendinopathy 4. Tarsal tunnel syndrome 5. Anterior ankle impingement TEST AND RESULTS: AP, lateral, and oblique ankle radiographs were normal. An MRI revealed diffuse edema within the distal tibia and medial malleolus. Metabolic workup was normal except for vitamin D level of 15. FINAL WORKING DIAGNOSIS: Distal tibia and medial malleolus stress fracture TREATMENT AND OUTCOMES: 1.Patient started on 50,000 international units of vitamin D weekly for 12 weeks2.Non-operative treatment with a tall CAM walker boot with 6 weeks of non-weight bearing followed by 4 weeks of weight bearing as tolerated 3.CAM boot discontinued after 10 weeks and the patient was started in physical therapy4.Underwent 4 weeks of a return to run program5.Followed by 12 weeks of base and marathon training program 6.Experienced no setbacks and was pain free with running7.Completed half-marathon roughly 6 months from initial diagnosis