Patient presents with complaints consistent with posterior tibial tendon dysfunction (PTTD), possibly posterior tibial tendonitis.  Symptoms include medial ankle pain, pain along the course of the posterior tibial tendon, and difficulty with weight-bearing activities, particularly during heel raise and single-leg stance.  Onset of pain was gradual and described as aching, worsening with activity and improving with rest.  Patient reports no specific trauma or injury.  Physical examination reveals tenderness to palpation along the posterior tibial tendon, mild swelling and warmth over the medial ankle, and pain with resisted plantarflexion and inversion.  Positive too many toes sign observed.  Limited range of motion noted during ankle dorsiflexion and eversion.  Differential diagnosis includes medial malleolar stress fracture, tarsal tunnel syndrome, and deltoid ligament sprain.  Assessment suggests posterior tibial tendonitis.  Plan includes conservative management with rest, ice, compression, elevation (RICE), nonsteroidal anti-inflammatory drugs (NSAIDs) for pain management, and a referral to physical therapy for strengthening exercises and gait training.  Orthotics or bracing may be considered for additional support.  Patient education provided regarding activity modification and proper footwear.  Follow-up scheduled in two weeks to assess response to treatment and consider further imaging (e.g., ultrasound, MRI) if symptoms persist or worsen.  ICD-10 code M72.2 for posterior tibial tendinitis will be used for billing purposes.