Closed Rupture of the Flexor Hallucis Longus Tendon with Evaluation of the Mechanism of Injury: A Case Report.

Abstract

The flexor hallucis longus tendon is prone to injury in the foot and ankle region, including tears and partial ruptures1-3, especially among ballet dancers and athletes4-7 who engage in repetitive push-off maneuvers, resulting in inflammation (Fig. 1). Complete interruption of the tendon is often associated with lacerations8-10. More rarely, these injuries present as closed complete ruptures whose precise etiology is still not well understood1,11-19. Fig. 1 Plantar aspect of the right foot. FDL = flexor digitorum longus, FHL = flexor hallucis longus, H’s K = knot of Henry, TEAR = tear in the flexor hallucis longus tendon, and SLIP TO FDL = slip to the flexor digitorum longus tendon from the flexor hallucis longus tendon. Reproduced with permission of Harry Hauck Jr. To our knowledge, Krackow, in 1980, was the first to describe a closed complete rupture of the flexor hallucis longus tendon; this traumatic rupture occurred in a thirty-four-year-old man who had dorsiflexed the ankle, foot, and great toe against resistance while diving11. Since then, only ten cases of closed complete rupture of the flexor hallucis longus tendon have been described in the literature1,11-19; these injuries are summarized in Table I. In this case report, we describe a patient with a closed rupture of the flexor hallucis longus tendon, with a special emphasis on the mechanism of injury. View this table: TABLE I Case Reports of Flexor Hallucis Longus Tendon Ruptures in the Literature* The patient was informed that data concerning the case would be submitted for publication, and he provided consent. A seventy-four-year-old white man ruptured the right flexor hallucis longus tendon while changing his trousers standing by a stairway. He had already negotiated the left leg and …