Biomechanical Evaluation of Knotless and Knotted All-Suture Anchor Repair Constructs in 4 Bankart Repair Configurations

Published:February 10, 2020DOI:


      To evaluate the biomechanical performance of Bankart repair using 1.8-mm knotless all-suture anchors in comparison to 1.8-mm knotted all-suture anchors with both simple and horizontal mattress stitch configurations.


      Thirty fresh-frozen human cadaveric shoulders were dissected to the capsule, leaving the glenoid and humeral capsular insertions intact. A standardized anteroinferior labral tear was created and repaired using 3 anchors. A 2 × 2 factorial design was implemented, with 6 matched pairs randomized between knotless and knotted anchor repairs and 6 matched pairs randomized into simple and horizontal mattress stitch configurations. In addition, 6 unpaired shoulders were used to evaluate the native capsulolabral state. First failure load, ultimate load, and stiffness were assessed. Linear mixed-effects modeling was used to compare endpoints. Digital image correlation was used to evaluate capsular strain throughout testing. Failure modes were reported qualitatively.


      The knotless all-suture anchor repair showed similar biomechanical strength to the knotted all-suture anchors for first failure load (coefficient, 142 N; 95% confidence interval [CI], –30 to 314 N; P = .12), ultimate load (coefficient, 11.1 N; 95% CI, –104.9 to 127.2 N; P = .847), and stiffness (coefficient, 3.4 N/mm2; 95% CI, –14.1 to 20.9 N/mm2; P = .697) when stitch configuration was held constant. No statistically significant differences were found on comparison of simple and mattress stitch configurations for first failure load (coefficient, –31 N; 95% CI, –205 to 143 N; P = .720), ultimate load (coefficient, 112 N; 95% CI, –321 to 97 N; P = .291), and stiffness (coefficient, –9.6 N/mm2; 95% CI, –27.3 to 8.1 N/mm2; P = .284) when anchor type was held constant. Specimens with knotless anchors and simple stitch techniques resulted in lower stiffness compared with the native state (P = .030). The knotless-mattress configuration resulted in significantly lower strain than the knotted-mattress (P = .037) and knotless-simple (P = .019) configurations and was the only configuration that did not result in a significant increase in strain compared with the intact specimens (P = .216). Fewer instances of suture slippage (loss of loop security) were observed with knotless anchors versus knotted anchors (11% vs 30%), and less soft-tissue failure was observed with the mattress stitch configuration versus the simple stitch configuration (36% vs 47%).


      Knotless and knotted all-suture anchor repairs with simple and mattress stitch configurations showed similar values of ultimate load, first failure load, and stiffness. However, the horizontal mattress stitch configuration proved to decrease capsular strain more similarly to the native state compared with the simple stitch configuration. Ultimate load and first failure load for all repairs were similar to those of the native state.

      Clinical Relevance

      Knotless all-suture anchors have a smaller diameter than solid anchors, can be inserted through curved guides, and preserve glenoid bone stock. This study presents knotless, tensionable all-suture anchor repair for labral tears that displays high biomechanical fixation strength, similar to the native capsulolabral state.
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        • Barber F.A.
        • Herbert M.A.
        • Beavis R.C.
        • Barrera Oro F.
        Suture anchor materials, eyelets, and designs: Update 2008.
        Arthroscopy. 2008; 24: 859-867
        • Ee G.W.
        • Mohamed S.
        • Tan A.H.
        Long term results of arthroscopic Bankart repair for traumatic anterior shoulder instability.
        J Orthop Surg Res. 2011; 6: 28
        • Hayashida K.
        • Yoneda M.
        • Mizuno N.
        • Fukushima S.
        • Nakagawa S.
        Arthroscopic Bankart repair with knotless suture anchor for traumatic anterior shoulder instability: Results of short-term follow-up.
        Arthroscopy. 2006; 22: 620-626
        • Mueller M.B.
        • Fredrich H.H.
        • Steinhauser E.
        • Schreiber U.
        • Arians A.
        • Imhoff A.B.
        Biomechanical evaluation of different suture anchors for the stabilization of anterior labrum lesions.
        Arthroscopy. 2005; 21: 611-619
        • Nho S.J.
        • Provencher M.T.
        • Seroyer S.T.
        • Romeo A.A.
        Bioabsorbable anchors in glenohumeral shoulder surgery.
        Arthroscopy. 2009; 25: 788-793
        • Oh J.H.
        • Lee H.K.
        • Kim J.Y.
        • Kim S.H.
        • Gong H.S.
        Clinical and radiologic outcomes of arthroscopic glenoid labrum repair with the BioKnotless suture anchor.
        Am J Sports Med. 2009; 37: 2340-2348
        • Szyluk K.
        • Jasinski A.
        • Widuchowski W.
        • Mielnik M.
        • Koczy B.
        Results of arthroscopic Bankart lesion repair in patients with post-traumatic anterior instability of the shoulder and a non-engaging Hill-Sachs lesion with a suture anchor after a minimum of 6-year follow-up.
        Med Sci Monit. 2015; 21: 2331-2338
        • Mazzocca A.D.
        • Chowaniec D.
        • Cote M.P.
        • et al.
        Biomechanical evaluation of classic solid and novel all-soft suture anchors for glenoid labral repair.
        Arthroscopy. 2012; 28: 642-648
        • Willemot L.
        • Elfadalli R.
        • Jaspars K.C.
        • et al.
        Radiological and clinical outcome of arthroscopic labral repair with all-suture anchors.
        Acta Orthop Belg. 2016; 82: 174-178
        • Bents E.J.
        • Brady P.C.
        • Adams C.R.
        • Tokish J.M.
        • Higgins L.D.
        • Denard P.J.
        Patient-reported outcomes of knotted and knotless glenohumeral labral repairs are equivalent.
        Am J Orthop (Belle Mead NJ). 2017; 46: 279-283
        • Nho S.J.
        • Frank R.M.
        • Van Thiel G.S.
        • et al.
        A biomechanical analysis of anterior Bankart repair using suture anchors.
        Am J Sports Med. 2010; 38: 1405-1412
        • Dines J.S.
        • Elattrache N.S.
        Horizontal mattress with a knotless anchor to better recreate the normal superior labrum anatomy.
        Arthroscopy. 2008; 24: 1422-1425
        • Ng D.Z.
        • Kumar V.P.
        Arthroscopic Bankart repair using knot-tying versus knotless suture anchors: Is there a difference?.
        Arthroscopy. 2014; 30: 422-427
        • Cooper D.E.
        • Arnoczky S.P.
        • O'Brien S.J.
        • Warren R.F.
        • DiCarlo E.
        • Allen A.A.
        Anatomy, histology, and vascularity of the glenoid labrum. An anatomical study.
        J Bone Joint Surg Am. 1992; 74: 46-52
        • Hagstrom L.S.
        • Marzo J.M.
        Simple versus horizontal suture anchor repair of Bankart lesions: Which better restores labral anatomy?.
        Arthroscopy. 2013; 29: 325-329
        • Ostermann R.C.
        • Hofbauer M.
        • Platzer P.
        • Moen T.C.
        The "labral bridge": A novel technique for arthroscopic anatomic knotless Bankart repair.
        Arthrosc Tech. 2015; 4: e91-95
        • Judson C.H.
        • Voss A.
        • Obopilwe E.
        • Dyrna F.
        • Arciero R.A.
        • Shea K.P.
        An anatomic and biomechanical comparison of Bankart repair configurations.
        Am J Sports Med. 2017; 45: 3004-3009
        • Martetschläger F.
        • Michalski M.P.
        • Jansson K.S.
        • Wijdicks C.A.
        • Millett P.J.
        Biomechanical evaluation of knotless anterior and posterior Bankart repairs.
        Knee Surg Sports Traumatol Arthrosc. 2014; 22: 2228-2236
        • Lionello G.
        • Sirieix C.
        • Baleani M.
        An effective procedure to create a speckle pattern on biological soft tissue for digital image correlation measurements.
        J Mech Behav Biomed Mater. 2014; 39: 1-8
        • Pinheiro J.
        • Bates D.
        • DebRoy S.
        • Sarkar D.
        • R Core Team
        nlme: Linear and nonlinear mixed effects models.
        R Foundation for Statistical Computing, Vienna2018
        • R Core Team. R
        A language and environment for statistical computing.
        R Foundation for Statistical Computing, Vienna2018
        • Provencher M.T.
        • Verma N.
        • Obopilwe E.
        • et al.
        A biomechanical analysis of capsular plication versus anchor repair of the shoulder: Can the labrum be used as a suture anchor?.
        Arthroscopy. 2008; 24: 210-216
        • Park J.Y.
        • Chung S.W.
        • Lee J.S.
        • Oh K.S.
        • Lee J.H.
        Comparison of clinical and radiographic outcomes of vertical simple stitch versus modified Mason-Allen stitch in arthroscopic Bankart repairs: A prospective randomized controlled study.
        Am J Sports Med. 2019; 47: 398-407

      Linked Article

      • Editorial Commentary: A New Star Is Born—The Knotless All-Suture Anchor
        ArthroscopyVol. 36Issue 6
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          The development of all-suture anchors has revolutionized the field of orthopaedic surgery. Biomechanically, these anchors have similar or better strength when compared with conventional solid anchors. All-suture anchors allow the suture to be placed in cortical bone tunnels, with a smaller diameter, thus limiting potential iatrogenic damage. To avoid the inconsistencies of knot tying and eliminate knot stacks, knotless all-suture anchors have been increasingly used in arthroscopic surgery. This may reduce the potential risk of knot abrasion, which can lead to soft-tissue or cartilage damage.
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