Arthroscopic Repair of Rotator Cuff Injury: An Analysis of Function, Muscular Strength and Pain Between Single Row and Double Row Techniques.

 To evaluate the patients submitted to arthroscopic repair of the rotator cuff (RC), comparing the functional results, muscle strength, and pain obtained after single row (SR) and double row (DR) techniques.  Data were collected at the postoperative follow-up (minimum of 12 months) of 128 patients submitted to arthroscopic RC repair from 2011 to 2018. The clinical-functional variables were collected through the clinical examination, and the demographic, surgical and injury variables of the RC were collected from the electronic medical records. The results were compared between the SR and DR groups.  The DR group showed higher anterior elevation strength when compared with the SR group (SF: 4.72 ± 2.73 kg versus DR: 5.90 ± 2.73 kg;  = 0.017). The other variables of muscle strength, Constant-Murley Score, University of California at Los Angeles Shoulder Rating Scale (UCLA), and pain, were similar. Performing the stratification by size, in the analysis of small and medium injuries, no differences were found between the groups. However, in the analysis of large and extensive injuries, patients submitted to DR presented superiority of both muscle lifting strength (SF: 3.98 ± 2.24 kg versus DR: 6.39 ± 2.73 kg) and Constant score (SF: 81 ± 10 versus DR: 88 ± 7).  The use of the DR technique in arthroscopic RC repair allowed higher levels of muscle strength for anterior shoulder elevation when compared with the SF technique. Data stratification in large and extensive injuries showed superiority of anterior shoulder elevation muscle strength and of the Constant score in patients submitted to DR.