Background <p>This study aims to compare histopathological results following a 6-week postoperative follow-up of biceps tenodesis (BT) at 1/3 median, 1/3 posterior, and 1/3 anterior locations to the rotator cuff footprint (RCF) in cases of massive irreparable rotator cuff tears (MIRCT).</p> Materials and methods <p>Thirty rabbits were assigned to three groups. BT for superior capsular reconstruction (SCR) was performed on rabbits 1–10 at the 1/3 median part of the RCF along the sagittal axis using a transosseous reinforced suture with the modified Mason-Allen technique, maintaining consistent pressure in the groove (Group 1). In rabbits 11–20 (Group 2), tenodesis was performed 1/3 posterior to the RCF, while rabbits 21–30 (Group 3) underwent tenodesis 1/3 anterior to the RCF. Following the 6-week follow-up, the shoulders were excised en bloc, and histopathological evaluation was conducted using a modified Bonar’s scale. Results were statistically compared among the groups.</p> Results <p>The level of cell morphology was significantly lower in Group 2 compared to the other groups (<i>p</i> &lt; 0.05). The extracellular matrix level was also significantly lower in Group 2 compared to the others (<i>p</i> &lt; 0.05). There were no statistically significant differences in collagen levels across Groups 1, 2, and 3 (<i>p</i> &gt; 0.05), nor in cellularity levels among the groups (<i>p</i> &gt; 0.05). General score evaluation levels were significantly lower in Group 2 than in the other groups (<i>p</i> &lt; 0.05).</p> Dicsussion <p>BT performed on the 1/3 posterior part of the RCF demonstrated greater success compared to procedures conducted at the 1/3 median and 1/3 anterior locations for MIRCT.</p>