Os Trigonum Fracture: Case Report

Bilateral Os Trigonum Fracture Treated With Simultaneous Posterior Ankle Arthroscopy

“…An os trigonum fracture is an uncommon condition 17,18 ; resultantly, only 12 cases have been reported in the literature since 1927 (Table 2). [10][11][12][13]17,[19][20][21] All previous reports of this trauma were unilateral manifestations, making this study the first documented bilateral case. The mechanism of injury for this pathology is forced hyperplantar flexion that creates compression of the os trigonum by the posterior portion of the tibial plafond and posterosuperior aspect of the calcaneus, earning the nickname "nutcracker syndrome."…”

“…7,12,20 Therefore, for patients with unresolving symptoms after at least 6 weeks of conservative therapy, surgical treatment should be considered. 14,20,26 The standard surgery for os trigonum fracture is an open excision, which can be approached posterolaterally 19 or vertically along the midline. 10 Although there were no complications identified in our literature review of os trigonum fractures specifically (Table 2), a systematic review of open os trigonum excision using PM (59 patients) and PL (59 patients) approaches reported negative outcomes such as wound and neurological complications at rates between 8% and 21%.…”

“…22,23 Diagnosis is often challenging, and nondisplaced fractures are usually misdiagnosed as ankle sprains, peroneal tendinitis, or Achilles tendinitis. 10,11,19 Therefore, patients with hyperplantar flexion injury history, persistent posterior ankle pain, inability to bear weight, 11,13 and reproducible pain on plantar flexion should raise suspicion. A negative radiograph does not rule out the injury, 7,11 necessitating additional investigation with CT and MRI scans.…”

“…The mechanism of injury for this pathology is forced hyperplantar flexion that creates compression of the os trigonum by the posterior portion of the tibial plafond and posterosuperior aspect of the calcaneus, earning the nickname “nutcracker syndrome.” 22 , 23 Diagnosis is often challenging, and nondisplaced fractures are usually misdiagnosed as ankle sprains, peroneal tendinitis, or Achilles tendinitis. 10 , 11 , 19 Therefore, patients with hyperplantar flexion injury history, persistent posterior ankle pain, inability to bear weight, 11 , 13 and reproducible pain on plantar flexion should raise suspicion. A negative radiograph does not rule out the injury, 7 , 11 necessitating additional investigation with CT and MRI scans.…”

“… 11 - 13 , 24 The success rate is approximately 70%. 10 11 12 13 , 17 , 19 - 21 Whether osseous union is achieved, it has been proposed that if the patient is asymptomatic, no additional treatment is indicated. 25 However, this claim has been disputed by other studies of symptomatic nonunion 10 , 11 , 20 where associated pain and inflammation have been demonstrated.…”