Reusing cadaveric humeri for fracture testing after testing simulated rotator cuff tendon repairs

Abstract

The financial cost of using human tissues in biomedical testing and surgical reconstruction is predicted to increase at a rate that is disproportionately greater than other materials used in biomechanical testing. Our first hypothesis is that cadaveric proximal humeri that had undergone monotonic failure testing of simulated rotator cuff repairs would not differ in ultimate fracture loads or in energy absorbed to fracture when compared to controls (i.e., bones without cuff repairs). Our second hypothesis is that there can be substantial cost savings if these cadaveric proximal humeri, with simulated cuff repairs, can be re-used for fracture testing. Results of fracture tests (conducted in a backwards fall configuration) and cost analysis support both hypotheses. Hence, the bones that had undergone monotonic failure tests of various rotator cuff repair techniques can be re-used in fracture tests because their load-carrying capacity is not significantly reduced.

Keywords: bone; cost analysis; fracture; humerus; in vitro; rotator cuff repair.

FIG. 1.

Transosseous anchor double knot (TOAK) fixation. This construct is effectively a quasi double-row repair with a suture bridge. The inset drawing shows the superficial suture of the trans-osseous component of the TOAK construct. A metal anchor is depicted in this illustration.

FIG. 2.

(A) Diagram of load orientation; a left humerus is depicted in lateral view. A, anterior; P, posterior. (B) View of the superior humeral head showing location of anchors (medial row) and area where the force was applied to the posterior-superior aspect of the humeral head. A, anterior; M, medial.