Arthroscopic SLAP IIb Repair Using Knot-Tying Versus Knotless Suture Anchors: Is There a Difference?
TAKE-HOME POINTS
- SLAP IIb tears are common injuries in overhead athletes, yet surgical outcomes are variable, with throwers commonly having difficulty with return to play at the same level.
- In this study, 92% of athletes returned to play post-operatively, yet only around 55% returned at the same level.
- In overhead athletes, overall return to play was 85.7%, yet only 39.3% returned at the same level.
- Knotless fixation required less revision surgery and had higher outcome scores and return to play when compared to knotted fixation; however, this did not reach statistical significance.
- Knotless fixation should be considered in SLAP IIb repairs given their lower profile leading to less rotator cuff irritation, the ability to better provide more consistent tensioning, and decreased surgical time.
Further, as shown by Dines and colleagues25, knotless anchors may help to better restore the meniscoid anatomy of the superior labrum better than knotted suture anchors. With regards to fixation strength, Uggen and colleagues26, using a cadaveric model, found no difference in initial fixation strength of knotless and traditional suture anchor repair of SLAP II tears, and both restored glenohumeral rotation without over-constraining the shoulder.
Despite the shorter operative time, lower profile, and more consistent tensioning with knotless anchors, the literature is limited with regard to evaluating patient outcomes. In a study by Yung and colleagues13 14 of the 16 patients with type II SLAP tears were treated with knotless anchors, and the authors found that 31.3% of patients had an excellent UCLA score while 43.8% had a good score. This is similar to the outcomes illustrated in studies by both Friel and colleagues20 and Sayde and colleagues.16 In a more recent study, Yang and colleagues27 did find some benefit in regard to ROM with knotless fixation. Their study consisted of 21 patients who underwent surgery with traditional knotted anchor fixation and 20 who underwent knotless horizontal mattress fixation. They found an average UCLA score of 37.6 and ASES score of 91.5 in patients undergoing knotless fixation, and the knotless fixation group had 5% greater total ROM, 15.6% more internal rotation at abduction, and 11.4% more external rotation at the side as compared with patients undergoing the traditional knotted technique. When compared with the current study, this study also had a significantly shorter follow-up period of 3 years.27 In a 2017 study, Bents and colleagues28 compared 44 patients who underwent knotless and 119 who underwent knotted fixation of SLAP tears. They found no statistically significant difference between knotless and knotted fixation in the ASES score, Visual Analog Scale (VAS), ASES, or Veterans RAND 12-Item Health Survey (VR-12) at 1 year postoperatively. Their outcomes were similar to those of the current study, but as in other mentioned literature, the study by Bents and colleagues28 included multiple surgeons with different postoperative protocols, was not limited to SLAP IIb tears, and also had a shorter follow-up of 1 year. Like Kocaoglu and colleagues22, Bents and colleagues did find knotless anchors to be more efficient, as operative time was reduced by 5.3 minutes per anchor. This likely would have a significant impact on surgical cost and surgeon productivity.28
One limitation of the current study was that despite the inclusion of >70 patients, the study was still significantly underpowered. It was determined that >300 patients in each group would be required to detect a significant difference in the revision rate between the 2 anchor types. Also, due to the retrospective nature of this study, no preoperative scores were collected. The inclusion of objective clinical measurements and follow-up imaging evaluating the rotator cuff and other anatomy would also be of interest.
Although statistical significance was not achieved, there was a trend toward knotless fixation requiring less revision surgery and having higher RTP, ASES, and KJOC scores when compared with traditional knotted fixation at 6.5-year follow-up. Larger studies with longer follow-up periods are necessary to determine the effects of knotted and knotless anchors on rotator cuff tears, patient reported outcomes, and RTP. These complications have been shown in the literature, mostly in case reports, and typically develop over a longer period.23 Despite this, other advantages of knotless fixation, such as its lower profile, the ability to better provide consistent tensioning, and decreased surgical time are important to consider.
