Safe Zone Technique Improves Suture Placement During Remplissage

OBJECTIVES: Recent studies have raised concern over the accuracy of suture passage into the infraspinatus tendon during remplissage. Our purpose was to evaluate the accuracy of suture passage during remplissage and identify surface landmarks to improve accuracy. Our secondary purpose was to validate the use of these identified landmarks to improve accuracy of suture passage through the infraspinatus tendon. METHODS: 12 cadaveric specimens were used. In the first 6 specimens (control group), standard arthroscopic remplissage was performed. Specimens were dissected to quantify the location of suture passage in reference to the posterolateral acromion (PLA) and to identify the location of posterior cuff penetration. After analyzing the control group specimens a “safe zone” (SZ) was identified to improve accuracy of passage and increase infraspinatus tendon penetration. For final 6 specimens, the safe zone technique was utilized for suture passage during arthroscopic remplissage. Specimens were again dissected to analyze the accuracy of suture passage and location of penetration. Results were compared to the control group. RESULTS: For the control group, 24 sutures were passed. 25.0% (6/24) were passed through the infraspinatus tendon, and 75%(18/75) were through the teres or infraspinatus muscle or MTJ. Sutures passage through the infraspinatus were an average of 25±5.4 mm distal to the PLA, while teres minor sutures were an average of 35.8±5.7mm distal to the PLA. If passes were less than 3 cm distal to the PLA, there was a significantly higher rate of infraspinatus tendon penetration (odds ratio[OR]=25 ,p<0.01). Sutures passing through muscle and MTJ were significantly more medial than those passing through tendon, at an average 8.1±5.1mm lateral to the PLA compared to 14.5±5.5mm (p<0.02). Passes were more likely to be in tendon, rather than muscle or MTJ if greater than 1 cm lateral to the PLA (p=0.013). The safe zone was defined as passing all tenodesis sutures greater than 1 cm lateral and less then 3cm distal to the PLA. Utilizing this technique, 24 sutures were also passed arthroscopically in the remaining 6 specimens. 83.3% (20/24) were in the infraspinatus tendon, which was significantly improved from the control group (p<0.01). Only, 4.2% (1/24) of attempted passes in the SZ group passed through the muscle or MTJ which was also significantly improved from the control group (p<0.01). Prevention of over-medialization significantly improved using the SZ as represented by both anchors having suture passage significantly more lateral (6-10mm) than the control group (p<0.01). There was also an improvement in the precision of suture passes with utilization of the SZ, as overall precision (SD) improved in 75% of sutures passes. CONCLUSION: We found standard remplissage suture passage was inaccurate with only 25% of sutures penetrating the infraspinatus tendon. We recommend utilization of the “safe zone” technique, which consists of passing sutures 1 cm lateral and within 3 cm distal of the PLA. Furthermore this study validates that the “safe zone” technique, demonstrating significant improvement in accuracy of suture passage into the infraspinatus tendon and prevented over-medialization with muscle penetration. The safe zone technique provides a reproducible method that may prove useful to prevent previously reported complications associated with arthroscopic remplissage.