Original Article
Arthroscopic Excision of a Symptomatic Os Trigonum

Presented at the 2014 Arthroscopy Association of North America 33rd Annual Meeting, May 2, 2014, Hollywood, Florida.
https://doi.org/10.1016/j.arthro.2015.04.086Get rights and content

Purpose

To report the clinical outcomes of arthroscopic excision for a symptomatic os trigonum initially viewing through the posteromedial ankle portal with the motorized instrument in the posterolateral portal.

Methods

A retrospective review of a consecutive series of patients with symptomatic os trigonum failing nonoperative management and treated with arthroscopic excision was performed. Demographic data, clinical data, American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot scores, and Single Assessment Numeric Evaluation scores were obtained. Any complications and the time required to return to sports or full activities were recorded.

Results

Twenty-four patients with an arthroscopic excision of a symptomatic os trigonum were included. There were 13 male and 11 female patients. The average age was 36.7 ± 17 years. Twenty-one isolated os trigonum excisions and 3 excisions combined with other procedures were studied. At a mean follow-up of 26 months (range, 24 to 31 months), average preoperative AOFAS scores significantly improved from 55.3 to 92.3 postoperatively (P < .0001). The preoperative AOFAS function component improved from 17.1 to 33.8 (P < .0001). The mean postoperative Single Assessment Numeric Evaluation score was 90. Patients reported full activity at an average of 1.5 months with no limitations at an average of 7.8 months after surgery. The only complication was a posterior tibial nerve calcaneal branch neurapraxia.

Conclusions

Arthroscopic excision in the prone position without traction of a symptomatic os trigonum viewing initially through the posteromedial portal with a high-speed burr in the posterolateral portal resulted in significantly improved AOFAS scores with a single transient neurapraxia in 24 patients. Patients returned to their normal daily activities without limitations at an average of 1.5 months.

Level of Evidence

Level IV, therapeutic case series.

Section snippets

Methods

A retrospective review from the senior author's (J.M.C.) database was performed evaluating a consecutive series of patients presenting with a symptomatic os trigonum starting in April 2012. Inclusion criteria consisted of patients with a symptomatic os trigonum verified by examination, imaging, and diagnostic injection who failed nonoperative management. Exclusion criteria included the absence of an os trigonum, the presence of Outerbridge grade 3 or 4 osteoarthritic changes in the ankle, and

Results

Twenty-four patients with a symptomatic os trigonum were included in this study. There were 13 male and 11 female patients. The right ankle was involved in 9 and the left in 15. The average age was 36.7 ± 17 years (range, 15 to 82 years). There were 4 patients in whom symptom onset was associated with injury or trauma, and 20 described a gradual onset. Of the 24 procedures, 5 were isolated excisions of the os trigonum and 19 were associated with other procedures. These included tenolysis of the

Discussion

Arthroscopic excision of a symptomatic os trigonum in the prone position without traction, viewing first through the posteromedial portal and then through the posterolateral portal and using a high-speed burr in the posterolateral portal and then the medial portal, is both safe and effective. This technique provides comparable outcomes to other approaches, as well as a low complication rate, and resulted in significantly improved AOFAS scores.

Arthroscopic excision of a symptomatic os trigonum

Conclusions

Arthroscopic excision in the prone position without traction of a symptomatic os trigonum viewing initially through the posteromedial portal with a high-speed burr in the posterolateral portal resulted in significantly improved AOFAS scores with a single transient neurapraxia in 24 patients. Patients returned to their normal daily activities without limitations at an average of 1.5 months.

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  • Cited by (0)

    The authors report the following potential conflict of interest or source of funding: J.M.C. receives support from Arthrex. F.A.B. receives support from DePuy Mitek, Linvatec, and Arthrex.

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