Comparable outcomes of arthroscopic and mini-open tightrope fixation for acute acromioclavicular joint dislocations

Acute high-grade acromioclavicular (AC) joint dislocations are commonly treated surgically, with multiple fixation options available. Arthroscopic TightRope (AT) and mini-open TightRope (MOT) techniques are widely used, but comparative evidence remains limited. In this retrospective comparative study, 96 patients with Rockwood type III–V AC joint dislocations were treated between 2018 and 2023 using either AT (n = 52) or MOT (n = 44). Two patients lost to follow-up were excluded. Primary outcomes included Constant–Murley and UCLA scores, while secondary outcomes were visual analog scale (VAS) pain scores, coracoclavicular (CC) distance on radiographs, operative time, and complications. The sample size/power calculation was corrected (two-group comparison, α = 0.05, achieved power ~ 90% with d ≈ 0.67). A sensitivity analysis restricted to Rockwood IV–V was additionally performed to test robustness. At one year, both groups showed significant improvements in Constant–Murley and UCLA scores (p < 0.001 within groups) with no between-group differences (p > 0.05). The mean difference in operative time between the groups was 14.3 min (95% CI 11.5–17.1, p < 0.001). CC distance difference between groups was 0.2 mm (95% CI − 0.3 to 0.7, p = 0.41), indicating similar radiological stability. Complication rates were low and comparable. The IV–V–only sensitivity analysis yielded results consistent with the overall cohort. AT and MOT provide comparable one-year functional outcomes, pain relief, and radiological stability in acute AC dislocations. Differences were limited to perioperative parameters (longer operative time with arthroscopy). Choice of technique should be individualized based on patient factors and surgeon expertise.