Insertional versus non-insertional tendoachilles tears: a comparative analysis of various predisposing factors and outcome following a repair

Abstract

Background: Association of tendon degeneration, pre-existing posterior heel pain, Haglund's bump, retrocalcaneal spur, and mode of injury varies for the insertional and non-insertional type of tendoachilles tears (TA).

Purpose: The study compares the various predisposing factors that determine the distinct type of TA tear and the outcome following a repair.

Methods: This is a retrospective study of the patients who underwent tendoachilles repair during January 2012-June 2018. Patients above 18 years with a minimum follow-up of two years were included. Patients with calcaneal tuberosity avulsions, prior surgeries, and open injuries were excluded. Patients were divided into groups 1 (insertional tears (IT)) and 2 (non-insertional tears (NIT)), and further subdivided based on the tendon degeneration (as D-degenerative and N-normal sub types) from ultrasound findings. AOFAS score and predisposing factors like degeneration, posterior heel pain, Haglund's bump, spur, and mechanism of injury were compared between the groups.

Results: The study included N = 146 with a mean age of 51.6 years and mean follow-up of 38.6 (range 24 to 96) months. IT associated with degeneration (IT-D) had a trivial fall as the predominant mechanism (P < 0.001). All patients had significant postoperative improvement of scores with no significant difference between the groups (P = 0.59) and subgroups (P = 0.27).75.34% had degenerative tendon, of which 64.5% were in the IT group and the rest in the NIT group (P = 0.02). 51.4% patients had a Haglund bump in the IT group and n.s. (P = 0.9). Forty-seven percent of patients had pre-existing posterior heel pain, 68% in IT and 32% in NIT (P = 0.04). Subgroup analysis revealed 65% of patients were in the IT-D subgroup (P < 0.001).

Conclusion: Predisposing factors like posterior heel pain, tendon degeneration, and trivial trauma have a strong propensity for insertional TA tear. In contrast, the prominence of Haglund's bump does not predispose to a distinct type of TA tears. The outcome following a surgical repair-yields good results with no difference between the two groups.

Keywords: Haglund’s bump; Insertional tendoachilles tear; Non-insertional tendoachilles tear; Posterior heel pain; Retrocalcaneal spur; Tendinopathy; Tendon degeneration.