Objectives: Treatment options for massive irreparable rotator cuff tears, in middle aged adults, consists of tendon transfer or superior capsular reconstruction (SCR). The purpose of this study was to evaluate if transfer of the latissimus dorsi tendon transfer is enhanced with combination of superior capsular reconstruction for treatment of massive irreparable rotator cuff tears. Methods: At a single institution, all consecutive patients undergoing transfer of the latissimus dorsi tendon with or without superior capsular reconstruction, between 2013 and 2016, for treatment of irreparable rotator cuff tears were evaluated. SCR, was indicated, in addition to latissimus transfer, for patients with impaired preoperative active abduction. All clinical notes, diagnostic imaging, and operative reports were reviewed in detail. Demographics, operative techniques, and radiographic parameters were collected and measured. Functional outcome scores were prospectively collected from patients. The primary outcome of the study was the Disability of Arm, Shoulder, Hand (DASH) score. The secondary outcomes of the study were the Visual Analog Scale (VAS) pain score, Single Assessment Numeric Evaluation (SANE) score, and the American Shoulder and Elbow Society (ASES) score. Results: At 3 years, there were a total of 26 latissimus dorsi tendon transfers performed in patients with irreparable rotator cuff tears. Of these, 8 patients underwent only latissimus dorsi tendon transfer and 18 patients underwent latissimus dorsi tendon transfer combined with a superior capsular reconstruction. Average age was 53 years old with the majority of patients being male (88%). The dominant extremity was involved in 22 (85%) of latissimus transfers and 14 (53%) of patients had previous surgery to address a rotator cuff tear. Follow-up, for the entire cohort, was on average 29 months. At final follow-up, there was no significant difference in physical examination or radiographic measurements between patients with latissimus transfer alone and those with latissimus transfer with SCR. All patients, undergoing either technique, showed significant improvement in both the DASH score (preoperative DASH=59.6, postoperative DASH=39.9, P=0.049) and VAS score (preoperative VAS=6.6, postoperative VAS=3.3, P=0.0006). However, those patients undergoing revision surgery, regardless of technique, showed significantly less improvement in the DASH score (P=0.005), VAS score (P=0.002), SANE score (P=0.005), and the ASES score (P=0.001). Transfer of the Latissimus tendon with SCR, in comparison to only tendon transfer, did not show any significant difference in the final DASH score (p-value=0.72). At the same time, there was no significant difference between latissimus transfer, with or without SCR, in the secondary outcomes of the VAS score(P=0.97), the SANE score(P=0.63), or the ASES score (P=0.74). Conclusion: This is the first study to report the outcomes of latissimus dorsi tendon transfer with superior capsular reconstruction in comparison to only latissimus dorsi tendon transfer for treatment of irreparable rotator cuff tears. The study suggests that transfer of the latissimus dorsi tendon in combination with superior capsular reconstruction, at short term follow-up of 2 years, may not significantly influence functional outcome. Rather, patients undergoing revision surgery, regardless of technique, may demonstrate smaller improvements in functional outcomes. Table 2. Range of Motion & Physical Examination in Latissimus Dorsi Tendon Transfer with/without SCR Lat Only (n=8) Lat + SCR (n=18) Preoperative Postoperative P-Value Preoperative Postoperative P-Value Range of Motion (Active) Abduction 135 ± 21.2 76.4 ± 18 0.04 75.4 ± 26.0 71.5 ± 22 0.80 Forward Flexion 106.9 ± 36.7 135.7 ± 32.2 0.15 103.5 ± 32.2 110.6 ± 45.4 0.35 External Rotation 36 ± 11.4 42.9 ± 15 0.80 25.3 ± 18.6 38.5 ± 16.3 0.04 Internal Rotation 65 ± 22.9 59.3 ± 12.4 0.55 54.4 ± 13.3 63.1 ± 13.0 0.08 Hornblower Sign 2 (25%) 2 (25%) 0.98 14 (78%) 2 (11%) 0.07 External Rotation Lag 6 (75%) 2 (25%) 0.34 17 (94%) 3 (17%) 0.01 Continuous data are reported as mean ± standard deviation. Categorical data reported as number (%). Table 4. Functional Outcomes at Final Follow-Up of Latissimus Dorsi Tendon Transfer with/without SCR Lat Only (n=8) Lat + SCR (n=18) Mean (Std Dev) Mean (Std Dev) P-Value Primary Outcome DASH 47.0 ± 39.8 42.5 ± 27.5 0.72 Secondary Outcome Vas 3.14 ± 3.5 3.4 ± 3.5 0.97 SANE 54.7 ± 38.5 60.9 ± 22.1 0.63 ASES 65.8 ± 36.3 60.6 ± 30.9 0.74 Constance 63.8 ± 31.0 50.3 ± 23.3 0.34