Using Interconnected Knotless Anchor for Suprapectoral Biceps Tenodesis Could Offer Improved Biomechanical Properties in a Cadaveric Model Fa-Chuan Kuan, M.D., Kai-Lan Hsu, M.D., Joe-Zhi Yen, M.D., Miin-Jye Wen, Ph.D., Ming-Long Yeh, Ph.D., Yueh Chen, M.D. M.Sc., and Wei-Ren Su, M.D. M.Sc. Purpose: To compare the biomechanical characteristics of the interconnected knotless anchor (IKA) fixation with the double knotless anchor (DKA) and interference screw (IS) fixation in the suprapectoral biceps tenodesis. Methods: In total, 24 fresh-frozen human cadaveric shoulders (mean age, 67.3  6 years) were used for the study. All the specimens were randomly divided into 3 experimental biceps tenodesis groups (n ¼ 8): IKA, DKA, and IS. After tenodesis, each specimen was preloaded at 5 N for 2 minutes, followed by a cyclic loading test from 5 to 70 N for 500 load cycles. Finally, a destructive axial load to failure test (1 mm/s) was performed. All the values, including ultimate failure load, stiffness, cyclic displacement, and mode of failure were evaluated. Results: The IKA provided the highest construct stiffness (38.9  7.7 N/mm) and ultimate failure load (288.3  47.6 N), the results for which were statistically better than the corresponding results in the IS and DKA groups. In terms of cyclic displacement, there were no statistical differences among the 3 fixation constructs. The most common failure mode was biceps tendon tearing in IS group (7/8) and IKA group (8/8). In the contrast, suture slippage accounted for the most common failure mode in DKA. Conclusions: In suprapectoral bicep tenodesis, IKA fixation appears to offer improved construct stiffness and ultimate failure load while maintaining com- parable suture slippage as compared with IS fixation or DKA fixation in the current biomechanical study. Clinical Relevance: The IKA fixation compares favorably with other techniques and could be an alternative clinical option for suprapectoral biceps tenodesis. T he long head of biceps tendon lesion remains a source of anterior shoulder pain, and its manage- ment remains controversial. 1,2 Surgery is indicated in symptomatic patients who have long head of biceps tendon pathology or labral lesions for whom conser- vative treatment has failed. 3 The 2 most common pro- cedures, tenodesis and tenotomy, are well-established surgical techniques, and both have their proponents. 4-6 Although biceps tenotomy is a simple, quick surgery, in younger active populations, several studies have shown a preference for tenodesis regarding the cosmetic con- cerns and better muscle strength. 3-5,7 There are numerous popular techniques that have been described for tenodesis, including interference screw (IS), single or dual suture anchors, suspensory devices, and implant-free techniques. 7-14 The IS has been used as “inlay” technique and has been shown to have biomechanical superiority in a majority of From the Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan (F-C.K., K-L.H., M-L.Y.); Department of Or- thopaedic Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan (F-C.K., K-L.H., W-R.S.); National Cheng Kung University, Tainan, Taiwan (J-Z.Y.); Department of Statistics, Institute of Data Science, and Institute of Interna- tional Management, Tainan, Taiwan (M-J.W.); Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan (M-L.Y.); Department of Orthopaedic Surgery, Sin Lau Hospital, Tainan, Taiwan (Y.C.); and Skeleton Materials and Bio-compatibility Core Lab, Research Center of Clinical Medicine, National Cheng Kung University Hospital, Col- lege of Medicine, National Cheng Kung University, Tainan, Taiwan (W-R.S.). The authors report that they have no conflicts of interest in the authorship and publication of this article. Full ICMJE author disclosure forms are available for this article online, as supplementary material. Received October 5, 2019; accepted March 10, 2020. Address correspondence to Wei-Ren Su, M.D., M.Sc., Department of Or- thopaedic Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan, No. 138, Sheng-Li Road, Tainan City, Taiwan 70428. E-mail: suwr@ms28.hinet.net Ó 2020 by the Arthroscopy Association of North America 0749-8063/191173/$36.00 https://doi.org/10.1016/j.arthro.2020.03.028 Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol -, No - (Month), 2020: pp 1-8 1