Clinic and electromyographic results of latissimus dorsi transfer for irreparable posterosuperior rotator cuff tears

Background: This study examines the clinical and electromyographic results of latissimus dorsi transfer (LDT) using a combined open and arthroscopic technique for the treatment of symptomatic irreparable posterosuperior rotator cuff tears. Methods: Between 2006 and 2009, LDT was performed in 14 patients (mean age 59 years) with massive and symptomatic irreparable posterosuperior rotator cuff tear. The patients were examined preoperatively and postoperatively with mean follow-up of 52 months using the Constant score, and the integrity of the latissimus dorsi (LD) transfer was assessed by ultrasound in all cases and by MRI in ten cases. The functional activity of the LD transfer was compared to the non-operated side using surface electromyography. Results: All patients demonstrated a significant improvement in the Constant score (p = 0.001), from a preoperative score of 33 points (range 10-55 points) to a postoperative score of 59 points (range 13-80 points). The subjective assessment score was good to excellent in 12 patients (85%), and 11 patients (78%) would be willing to undergo surgery again. Integrity of the transferred tissue was confirmed in 13 of the 14 cases using ultrasound and MRI. Surface electromyographic signal showed increased activation of the transferred latissimus dorsi when performing active movements of external rotation (p = 0.002) and abduction-elevation (p = 0.009). Conclusions: Our results indicate that LDT significantly improves function and diminishes pain in patients with a massive posterosuperior rotator cuff tear. The combined open and arthroscopic technique preserves the deltoid muscle and controls the LD tendon reinsertion. Surface electromyographic signal confirms the active function of the transferred muscle.