Prevalence of Peroneal Tendon Instability in Calcaneus Fractures
Authors: Alhammoud Abduljabbar , Khamis Karim Mahmoud 
Published: September 2018

Category: Trauma Introduction/Purpose: Peroneal tendon instability (PI) associated with intraarticular calcaneal fractures is a significant and commonly missed injury. It has been proposed that the peroneal tendon dislocates with the occurrence of a calcaneal fracture because the axial force transmitted blows out the lateral wall causing either impingement of the peroneal tendon or avulsion of the superficial peroneal retinaculum from the distal fibula, allowing the peroneal tendons to dislocate anteriorly. To date, peroneal tendon instability with a calcaneal fracture has often passed undiagnosed by both radiologists and orthopedic surgeons. The present review aimed to determine the global reported prevalence of peroneal instability associated with calcaneus fractures according to the severity of the calcaneus fracture classification and the significance of a fleck sign as an indicator of PI. Methods: An electronic search of MEDLINE, Scopus, and Google Scholar was conducted until June 2017 without a date restriction and for English-language reports only in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Database searching was augmented by manual searches of common journals in the field (JBS, Foot and Ankle International, Foot and Ankle Surgery, Journal of Orthopedic Trauma). The reference lists from the identified studies were also scrutinized for any additional reports.The studies that reported the prevalence/incidence of peroneal tendon subluxation/ dislocation in association with a calcaneus fracture were included whereas patients with calcaneus fractures combined with other fractures, extraarticular calcaneus fractures, and old calcaneus fractures were excluded.The data analysis was performed using a comprehensive meta-analysis with a random effects model. Results: Of 31 initial studies, 9 were included, contain 1027 patients/1050 calcaneus fractures.Most of the patients were male, with an average age of 42.03 (range 18 to 79) years.Of the 1050 calcaneus fractures, PI was found in association with 305.The pooled odds ratio of the prevalence of PI with calcaneus fractures was 29.3%(95% CI 25.9%-32.9%; p < .001).The prevalence of PI increased with an increased fracture severity using the Sanders classification, with a prevalence of 5.4% with Sanders I,19% with Sanders II, 39.4% in Sanders III, and 49.5% with Sanders IV. The prevalence of PI in the tongue type fracture using the Essex-Lopresti classification was 19%, and for joint depression, was 30.8% (p < .001). The prevalence of the fleck sign as an indicator of PI was 54.7%. Conclusion: The global reported prevalence of peroneal tendon dislocation associated with intraarticular calcaneal fractures was 29.3% and that the prevalence of PI increases with increased severity of the calcaneus fracture. Such a high prevalence should raise suspicions in both radiologists and orthopedic surgeons about this injury. The assessment should begin with a careful review of preoperative radiographs to search for the fleck sign and CT scans for a dislocated tendon, followed later by intraoperative assessment of superior peroneal retinaculum integrity.