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

Abstract

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). The study compares the various predisposing factors that determine thedistinct type of TAtear and the outcome following a repair. This is a retrospective study of the patients who underwent tendoachilles repair during January 2012-June 2018. Patients above 18years with a minimum follow-up of twoyears 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. The study included N = 146 with a mean age of 51.6years 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 percentof 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). Predisposing factors like posterior heel pain, tendon degeneration, and trivial trauma have a strong propensity for insertional TAtear. 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.