Figure 1

A sketch map and results of the micro-CT evaluations and biomechanical testing: (a) Gross observation of specimen containing the supraspinatus and humerus of the surgical side in a three-dimensional reconstruction micro-computed tomography (micro-CT) image; (b) The vertical plane of the axis of the humerus bone tunnel in a sagittal view on the micro-CT image; new bone formation in the region of interest (ROI) within the bone tunnel, and the bone density at the tendon insertion site on the greater tuberosity, was revealed and evaluated (white rectangle); (c) Cross section of the axis of the humerus bone tunnel on the micro-CT image; the ROI is shown with new bone within the bone tunnel (white rectangle); (d) The cylinder scope including the bone tunnel with a diameter of 1.5 mm and depth of 3.0 mm from the joint surface in a three-dimensional reconstruction micro-CT image; (e–j) The results of micro-CT analysis revealed that ICA treatment effectively improved the bone quality. BS/BV: bone surface/volume ratio; BV/TV: bone volume fraction; Tb.Th: trabecular thickness; Tb.Sp: trabecular separation; Tb.N: trabecular number; (k,l) At two weeks, the mean ultimate load-to-failure was significantly higher in the ICA group compared with the control group. There was no significant difference in stiffness at two weeks between the two groups. At four weeks after operation, the average failure load and mean stiffness in the ICA group were significantly greater than in the control group. Scare bar = 1 mm. * p < 0.05 vs. the control group; ** p < 0.01 vs. the control group.