Biomechanical properties of a suture anchor system from human allogenic mineralized cortical bone matrix for rotator cuff repair

Abstract

Background Suture anchors (SAs) made of human allogenic mineralized cortical bone matrix are among the newest developments in orthopaedic and trauma surgery. Biomechanical properties of an allogenic mineralized suture anchor (AMSA) are not investigated until now. The primary objective was the biomechanical investigation of AMSA and comparing it to a metallic suture anchor (MSA) and a bioabsorbable suture anchor (BSA) placed at the greater tuberosity of the humeral head of cadaver humeri. Additionally, we assessed the biomechanical properties of the SAs with bone microarchitecture parameters. Methods First, bone microarchitecture of 12 fresh frozen human cadaver humeri from six donors was analyzed by high-resolution peripheral quantitative computed tomography. In total, 18 AMSAs, 9 MSAs, and 9 BSAs were implanted at a 60° angle. All three SA systems were systematically implanted alternating in three positions within the greater tuberosity (position 1: anterior, position 2: central, position 3: posterior) with a distance of 15 mm to each other. Biomechanical load to failure was measured in a uniaxial direction at 135°. Results Mean age of all specimens was 53.6 ± 9.1 years. For all bone microarchitecture measurements, linear regression slope estimates were negative which implies decreasing values with increasing age of specimens. Positioning of all three SA systems at the greater tuberosity was equally distributed (p = 0.827). Mean load to failure rates were higher for AMSA compared to MSA and BSA without reaching statistical significance between the groups (p = 0.427). Anchor displacement was comparable for all three SA systems, while there were significant differences regarding failure mode between all three SA systems (p < 0.001). Maximum load to failure was reached in all cases for AMSA, in 44.4% for MSA, and in 55.6% for BSA. Suture tear was observed in 55.6% for MSA and in 22.2% for BSA. Anchor breakage was solely seen for BSA (22.2%). No correlations were observed between bone microarchitecture parameters and load to failure rates of all three suture anchor systems. Conclusions The AMSA showed promising biomechanical properties for initial fixation strength for RCR. Since reduced BMD is an important issue for patients with chronic rotator cuff lesions, the AMSA is an interesting alternative to MSA and BSA. Also, the AMSA could improve healing of the enthesis.

Attaching artificial Achilles and tibialis cranialis tendons to bone using suture anchors in a rabbit model: assessment of outcomes

“…This highlights the importance of developing reliable and durable suture anchors to minimize the risk of failure. Several factors may affect the durability of suture anchors, including suture anchor design, material composition, and surgical techniques (Fleischli, 2018; Schanda et al, 2022).…”

Advanced strategies for constructing interfacial tissues of bone and tendon/ligament

“… 11 – 13 This is achieved through: (a) direct insertion of the broken enthesis into the bone tunnel, (b) mechanical anchoring of the reconstructed tissue using sutures or screws, and (c) minimizing externally-loaded forces to avoid accidental loosening or re-rupture after surgery. 14 – 19 Because traditional surgical treatments mainly focus on reestablishing enthesis anatomy while overlooking enthesis tissue regeneration, their efficacy in enthesis repair is limited. For instance, the reestablished enthesis may remain weakly connected to the bone for an extended time, leading to the formation of scar tissue instead of the desired healthy enthesis tissue, and in severe cases degeneration and lysis may occur, resulting in the loss of the anatomical reconnection between the enthesis and the bone.…”