Abstract
Objectives:
The outcomes of shoulder stabilization surgery have been reported extensively in other sports, however the return to sport rates and the outcomes of shoulder stabilization surgery in rock climbers has not been previously reported. It is paramount to investigate the outcomes among rock climbers, as rock climbing has its own unique biomechanical demands with significant loading of the upper extremity.
The primary objective of this study was to report the return to rock climbing, the return to any sports and instability recurrence rates after shoulder stabilization surgery in recreational rock-climbing individuals at 2 years postoperatively.
Methods:
Patients were identified from the Multicenter Orthopaedic Outcomes Network (MOON) shoulder instability cohort. This study was approved by the institutional review board across the 10 participating academic and private institutions in the United States. The eligibility criteria included patients with an age >= 14 years, who reported rock climbing as a recreational activity at the time of enrollment, underwent instability surgery and had a follow-up of 2 years.
The primary outcomes were the return to rock climbing rate, the return to any sport rate and the rate of recurrent instability at 2 years postoperatively. Recurrent instability was defined if a patient had a recurrent dislocation or reoperation for recurrent instability.
The secondary outcomes were:
1) identifying the predictors of return to rock climbing, return to any sport and recurrent instability rates at 2 years postoperatively
2) range of motion (ROM) at 4-6 months postoperatively
3) the patient-reported outcome measures (PROMs) at 2 years postoperatively.
The PROMs included the Single Assessment Numeric Evaluation (SANE), the American Shoulder and Elbow Surgeons (ASES) score and the Western-Ontario Shoulder Instability (WOSI) index. ROM measurements consisted of forward elevation, abduction, external rotation at the side, external rotation at 90° of abduction, and internal rotation at 90° of abduction.
The statistical analysis was performed with Stata/IC (Stata Statistical Software: Release 16. College Station, TX: StataCorp LLC.). Multivariate logistic regression analyses were performed to identify predictors of return to rock climbing, return to any sport and recurrence instability at 2 years postoperatively. The predictors were reported as odds ratios (ORs) with 95% confidence intervals (CIs). The predictors variables for the regression models were selected by using the backward elimination method until the F value of the model was sufficiently large.
Results:
A total of 104 recreational rock-climbing patients who underwent shoulder instability surgery were included in this study, of which 77.9% (N=81) were males. The mean age at the time of surgery was 28.8 years (range 15-54). The number of preoperative dislocations within 12 months of surgery were two to five in 40.4% of patients. The duration of instability symptoms was greater than a year in 52.9%. The direction of instability was anterior in 75.9%, posterior in 19.2%, superior in 3.85% and inferior in 0.96%. Out of 104 patients, 92 underwent a soft-tissue stabilization procedure and 12 patients underwent a Latarjet procedure. Only 15 patients had a prior instability surgery (14.4%). Baseline characteristics are displayed in Table 1. The most common soft-tissue stabilization was an arthroscopic anterior capsulolabral repair (45.2%) (Table 2). Intraoperative evaluation revealed the most common capsulolabral tear positions was from 2:30 to 5:00 o’clock position assuming a right glenoid.
In terms of range of motion at 4-6 months postoperatively, there was no significant difference between pre- and postoperative ROM except for external rotation at the side which was less by an average of 6.9 degrees (P=0.005). Regarding PROMs at 2 years of follow-up, the postoperative mean SANE was 81.6 (SD ± 14), ASES score was 90.9 (SD ± 10.2), WOSI index was 75.1 (SD ± 17.6) and the SAS was 12.6 (SD ± 3.5). All PROMs have improved at the at 2 years of follow-up significantly. Table 3 displays the pre- and postoperative ROM and PROMs for all patients.
The rate of return to rock climbing was 58% (41 out of 71) at 2 years. The adjusted multivariate logistic regression analysis displayed that female had significantly higher odds of returning to rock climbing when compared to males with an OR of 35 (95% CI 2.7, 459.6) (Table 3). The return to any sport rate was 78% at 2 years (71 out of 91) with 70.4% (50 out of 71) returning to a similar or higher level compared to preinjury status. The adjusted multivariate logistic regression models demonstrated returning to any sport was associated with an OR of 0.74 (95% CI 0.59, 0.93) per unit increase in BMI. However, there were no significant predictors for returning to any sport to similar or higher level.
There were three total recurrent dislocations (2.9%) at the 2-year follow-up. Each of the three dislocations were treated with a revision surgery which included 1 revision labral repair, 1 Latarjet and 1 was an undisclosed return to the operating room. None of these revisions had a prior surgery. A multivariate logistic regression model demonstrated that reoperation/re-dislocation was significantly lower with an OR of 0.49 per unit increase in age (95% CI 0.25, 0.99; P value = 0.047) (Table 4).
Conclusions:
In recreational rock climbers who underwent shoulder stabilization surgery, this study has demonstrated that the return to rock climbing was moderate with a rate of 58% at 2 years of follow-up. Females were more likely to return to rock climbing. The return to any sport was high with a rate of 78%. Patients with a higher BMI had a lower likelihood of returning to any sport. The rate of recurrence following shoulder stabilization was low, with younger age being a significant risk factor.
