- Dicussion:
    - tendinitis is present but tendon remains at its normal length;
    - in a young patient consider accessory navicular;

- Non Operative Treatment:
    - arch supports, rubber-soled shoe w/ quarter-inch medial heel, sole wedge, UCBL;
    - immobilization in a short leg cast for 6 weeks;
    - NSAIDS;

- Surgical Treatment:
    - if tenosynovitis persists over several months, then consider tenosynovectomy;
    - w/ intra-tendinous elogation, consider tendon advancement and reattachment to the navicular;
    - w/ intra-substance elongation, it is necessary to restore the tendon to its proper tension

Posttraumatic posterior tibialis tendon insertional elongation with functional incompentency: a case report. 

Surgical treatment of stage I posterior tibial tendon dysfunction.   

Comparison of MRI and Local Anesthetic Tendon Sheath Injection in the Diagnosis of Posterior Tibial Tendon Tenosynovitis