Mid-term functional outcomes of arthroscopy-assisted lower trapezius transfer using doubled peroneus longus tendon

In relatively young and active patients without glenohumeral arthritis, massive irreparable rotator cuff tears (MIRCT) can be treated with tendon transfer. Arthroscopy-assisted lower trapezius transfer (LTT) for MIRCT needs an allograft such as the Achilles tendon, to bring its attachment to the greater tuberosity. The availability of allografts is limited, particularly in developing countries. The objective of our study is to describe the functional outcomes of arthroscopy-assisted lower trapezius transfer with the peroneus tendon autograft in MIRCT.

This is a retrospective single-center study from 2019 to 2024. Patients with previous scapular surgeries and neuromuscular disorders were excluded from the study. Arthroscopy-assisted LTT was performed with a doubled peroneus longus (PL) autograft. Functional outcomes were assessed using the constant score, disabilities of arm, shoulder and hand score (DASH) and the American Shoulder and Elbow Score (ASES). Muscle power was assessed using the Medical Research Council (MRC) grading.

Of the 21 patients, with the mean age of 60 years, who formed the part of the study, fatty atrophy of the involved muscles was grade 4 in 19 patients and grade 3 in 2 patients. Thirteen patients had stage 1 cuff arthropathy, and eight patients had stage 2 cuff arthropathy. Four patients with subscapularis tears underwent single-row out-of-the-box subscapularis repair. The mean follow-up was 4.04 years (range: 1-6 years). The mean external rotation (ER) preoperatively was 10°. The mean forward flexion (FF) preoperatively was 90°. The mean final follow-up ER was 38° (p < 0.001), and the mean final follow-up FF was 145° (p < 0.001). Visual analog score, constant score, DASH, and ASES showed a trend of significant improvement over time. Postoperatively, muscle power during final follow-up was 4 out of 5 in 10 patients, 4+ in 9 patients, and 3 in 2 patients. We experienced a failure in one patient due to an anchor pullout at the supraspinatus footprint. This patient underwent reverse shoulder arthroplasty at one year.

Our retrospective study showed that a lower trapezius transfer using a doubled PL autograft offered a reliable and effective option with satisfactory functional outcomes for addressing MIRCT, especially in resource-constrained environments thereby increasing the accessibility of advanced shoulder reconstructive procedures. However, further randomized controlled trials are needed to validate the findings of this study.

Level IV.