Temporal outcomes of shoulder arthroplasty

Abstract

Introduction: Rotator cuff tears can occur insidiously without a specific initiating event (non-traumatic), or from acute shoulder trauma (traumatic). The aim of this study was to determine if repairs of traumatic rotator cuff tears had better outcomes than repairs of non-traumatic rotator cuff tears. Methods: In this retrospective comparative study, the cohort consisted of 1300 consecutive patients who completed a preoperative questionnaire regarding their shoulder injury, had a systematic evaluation of shoulder range of motion and strength, a primary arthroscopic rotator cuff repair performed by a single surgeon, had anultrasound scan and the same subjective and objectivemeasurements made of their shoulder six months post-surgery. Post-hoc, this cohort was separated into two groups; those who reported no history of trauma (N=489) and those with a history of traumatic injury (N=811). Multiple logistic regression analyses were used to determine factors that affected rotator cuff integrity at six months. Results: Patients with traumatic rotator cuff tears were slightly younger (3 years), had larger tears by 0.6 cm2, stiffer shoulders (3–11∞) and came to surgery earlier (7 months) than those who could not recall a specific initiating event. Both groups had improved outcomes at sixmonthswith re-tear rates of 14% and12% in the traumatic and non-traumatic groups respectively (NS). In the both groups, larger intraoperative tear sizes predicted re-tears at six months (p<0.001). Those patients with shoulder trauma who waited longer than 24 months, had higher re-tear rates (20%) at six months compared to those who had their surgery earlier (13%) (p<0.05). Discussion:Recollectionof a traumatic initiatingeventhad little effect on the outcome of arthroscopic rotator cuff repair. Re-tears were predominantly predicted by intraoperative tear size. Previous studies that have used smaller sample sizes, foundno differences in postoperative re-tear rates based on time to surgery. In this study, duration of preoperative symptoms was important in predicting re-tears if patients recalled a specific initiating event, but not in patients who did not recall any specific initiating event. Patients with a history of trauma should therefore be encouraged to have their rotator cuff tears repaired within two years of their trauma. Limitations of this study include the retrospective design, and a relatively short follow-up time of six months.