Arthroscopic debridement of the talonavicular joint using dorsomedial and dorsolateral portals: a cadaveric study of safety and access.

PURPOSE

The purpose of this study was to examine the safety and access talonavicular arthroscopy provides for the purpose of arthrodesis through dorsomedial and dorsolateral portals in a cadaveric model.

METHODS

The talonavicular joints of 8 cadaveric specimens were arthroscopically debrided, by use of a dorsomedial instrumentation portal and a dorsolateral visualization portal. The specimens were dissected with the arthroscopic equipment left in place, the distances from the edge of the instrument to the neurovascular structures were measured, and the specimens were then examined for signs of damage. Finally, the naviculars and tali were removed, and the percentage of debrided subchondral bone was determined by use of ImageJ software (National Institutes of Health, Bethesda, MD).

RESULTS

Examination of the talonavicular joint showed mean subchondral debridement of 98.6% of the navicular and 83.2% of the talus. The dorsomedial portal had a median distance of 4.5 mm, 10.5 mm, and 7 mm to the superficial peroneal nerve, the medial terminal branch of the deep peroneal nerve, and the dorsalis pedis, respectively. The dorsolateral portal had a median distance of 1 mm to the lateral branch of the deep peroneal nerve, with the nerve found resting on the arthroscope in 2 specimens.

CONCLUSIONS

Arthroscopic debridement of the talonavicular joint is possible. Because of the risk of damage to the lateral terminal branch of the deep peroneal nerve, an alternative to the dorsolateral portal should be considered.

CLINICAL RELEVANCE

This study provides evidence that arthroscopic assisted talonavicular arthrodesis is possible but that further research is needed to ensure the safety of the technique.