The study's aim is to determine the incidence of flexor hallucis tendon tears associated with os trigonum excision. The study will then compare the length until functional return to play of the patients who had flexor hallucis tendon tears with concomitant os trigonum excision versus those without flexor hallucis tendon tears who underwent os trigonum excision. Lastly, the study will be evaluating the patient complaints and physical exam findings before and after surgery and compare those without flexor hallucis tendon tears to those with flexor hallucis tendon repair.

Posterior ankle pain syndrome has many etiologies. Two main causes of this are flexor hallucis tendon tear and os trigonum impingement. The current teaching is that patients with flexor hallucis longus tear complain of posterior medial ankle pain and those with posterior lateral ankle pain have an os trigonum impingement. It is also classically understood that patients with flexor hallucis tendon tears take longer to return to their pre-injury level of function. Our clinical experience refutes these reports and our study looks to further evaluate it.

This study brings back patients who were treated by the study doctor. The patient's preoperative evaluation will be reviewed including clinic notes and imaging. The operative reports for these patients will be reviewed to verify the surgery procedure performed. These patients will be included in the study and we will utilize the American Academy of Orthopedic Surgeons Foot, Ankle, and Lower Limb module that they have completed postoperatively. This measure of patient's functional and subjective satisfaction has already been completed by patients at their regularly scheduled follow up appointments and is available for review.

Prospectively, patients will be asked to return to the clinic for a follow-up evaluation, which includes a standard x-ray. All patients will be consented prior to data collection, minors included in this study will be asked to sign an assent as well. Many factors will be assessed such as; a range of motion test of the ankle utilizing goniometric technique, nerve path and function, stability ankle grading, radiologic findings, and patient-reported outcomes filled out pre and postoperatively.

Inclusion Criteria:

• Os trigonum excision with or without a flexor hallucis longus tear in an athletic population (recreational to competitive)
• Males and females ages 11-50 at time of surgery

Exclusion Criteria:

• Any other injury that will affect their return to play or recovery process
• Individuals not actively involved in athletic sport/activity
• Pregnant women
• Any other concomitant injuries

Prior patients of the study doctor from August 1996 to June 2017 that underwent os trigonum excision and of the athletic population (recreational to competitive).