¹Floyd K, ²Paul R, ³Sonnier J, ³Kemler B, ³Connors G, ³Sabitsky M, ³Tjoumakaris F, ³Freedman K
¹Lewis Kats School of Medicine, Philadelphia, PA, USA; ²Rothman Institute, Philadelphia, PA, USA; ³PA, USA

Objective
To determine whether patient-reported outcomes are associated with surgical timing utilizing a multivariate regression. No large studies have directly compared long-term outcomes in patients with Rockwood grade III-V acromioclavicular (AC) joint separations treated with acute vs. chronic repair. Therefore, the purpose of this study was to compare post-operative outcomes between patients who undergo high-grade AC joint surgery acutely (<4 weeks) vs chronically (>4 weeks).

Methods
AC joint surgery patients from 2010-2019 were included if they underwent primary AC joint surgery for a Rockwood grade III-V AC joint separation. Chart review was conducted to determine time from injury to surgery, Rockwood injury grade, and surgical technique. Post-operative complications, revisions, American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation (SANE) scores, and radiographic outcomes were collected. Radiographic outcomes were determined by measuring coracoclavicular (CC) distance on preoperative, immediate postoperative, and all follow-up anterior-posterior views of the operative shoulder. Multivariate regressions were conducted with post-operative ASES, SANE, and CC distance as the outcomes of interest.

Results
Overall, 221 patients (104 early, 117 delayed) with an average age of 40(+/-)15 years were included in this study. Significant differences in patient age, BMI, injury grade, surgical technique utilized, and pre-operative CC distance were observed between groups (all p<0.05). After controlling for confounding variables such as age, sex, BMI, injury grade, and surgical technique, multivariate regression found that time from injury to surgery was not related to post-operative ASES score (p=0.563), post-operative SANE score (p=0.441), or post-operative CC distance (p=0.760). Female patients had lower ASES scores than male patients (estimate: -8.25, 95% CI: -15.99 to -0.050, p=0.039), however, no other significant relationships were identified from multivariate regression.

Conclusion
Timing of AC joint surgery did not affect functional outcomes. Clinicians may counsel patients that either early or delayed surgery may be appropriate.

Level of Evidence
III (retrospective cohort study)