BACKGROUND: An individualized treatment algorithm (Copenhagen Achilles Rupture Treatment Algorithm (CARTA)) based on the ultrasonographic appearance of an acute Achilles tendon rupture has been developed aiming to select the correct patients for operative and non-operative treatment. The objective of this study is to investigate if this individualized treatment algorithm gives a better functional outcome than treating all patients either operatively or non-operatively per default.

METHODS/DESIGN: This study is conducted as a multicenter, three-armed randomized controlled trial. Participants are included from four hospitals in Denmark and randomized 1:1:1 to one of three parallel groups: 1) Intervention group-participants are treated according to an individualized treatment algorithm; 2) Control group A-participants are treated non-operatively; 3) Control group B-participants are treated operatively. The individualized treatment algorithm for the intervention group is based on an ultrasonographic examination; tendon overlap and elongation below 7% is to be treated non-operatively, while no tendon overlap and/or elongation above 7% will be treated operatively. Over a period of 3 years, 300 participants will be included. The primary outcome is the heel-rise work test at 12 months post-injury. Secondary outcomes are tendon elongation, the Achilles tendon Total Rupture Score (ATRS), the rate of re-ruptures, and other complications. The primary analysis will be conducted as an intention-to-treat analysis.

DISCUSSION: This trial will indicate if treatment of acute Achilles tendon rupture can be individualized based on elongation and tendon overlap. It is hypothesized that different patients will benefit from different treatments instead of offering all the same treatment.

TRIAL REGISTRATION: ClinicalTrials.gov, NCT03525964. Registered 16 May 2018.