Estudio de las plastias de dorsal ancho y redondo mayor en las artroplastias totales invertidas de hombro

Abstract

Reverse total shoulder arthroplasty (RTSA) has been shown to be effective in improving pain and restoring anterior elevation (AE) and abduction (ABD) in patients with pseudoparalysis of the shoulder secondary to rotator cuff arthropathy. When infraspinatus tendon (IET) and teres minor tendon (TmT) are involved, a deficit of external rotation that the RTSA alone cannot adress is stablished. Worse results of the RTSA are described in these patients. There is controversy regarding the treatment of these patients. The objective of this study is to analyze the patients with a reverse total shoulder arthroplasty with a latissimus dorsi and teres major tendon transfer from a clínical, functional, biomechanical and neurophysiological level. Goals: To study the patients operated of a RTSA with a latissimus dorsi and teres major tendon transfer from a clínical, functional, biomechanical and neurophysiological level. Compare the results obtained with the contralateral shoulder. To analyze the relationship between biomechanical results with clinical and functional results; and electromyographic results with clinical and functional results. Hypothesis: We maintain that patients who underwent a RTSA with a latissimus dorsi and teres major tendon transfer have strenght in external rotation greater than 50% of the strength in external rotation of the contralateral shoulder; that they obtain a clinical and functional improvement after the surgery; and that the electromyographic records of the transferred muscles maintain in time and are comparable to those obtained in the contralateral shoulder. Material and method: This is a cross-sectional observational study of cases and controls of all the patients operated with a RTSA with latissimus dorsi and teres major tendon transfer at the Hospital de Terrassa (Barcelona, Spain) between 2007 and 2015. The final sample are 10 patients. All were initially diagnosed with a massive rupture of the rotator cuff with involvement of the IET and TmT, both clinically and radiologically. A clinical and functional evaluation (Lag sign, Hornblower, Constant test); a biomechanical assessment using an isokinetic study; and a electromyographical study were performed on all the patients in both shoulders. The biomechanical results in ER of the operated shoulder are compared with 50% of the biomechanical results of the control shoulder in ER. The pre and postoperative evolution of the clinical and functional assessment has been analyzed. The EMG results of the operated shoulder have been compared with the EMG results of the control shoulder. Relationships between clinical, functional, biomechanical and electromyographic results have been sought. Results: No significant differences were found between the biomechanical results in ER of the operated shoulder and the 50% of the biomechanical results in ER of the control shoulder. A statistically significant improvement was found in the Constant test after the intervention, with a mean improvement of 30. 9 points (p <0. 00). No significant differences were found between the EMG results of the operated shoulder and the control shoulder. A relationship has been found between the electromyographic results of LD and TmTand the clinical and functional results in the operated shoulder. Conclusions: Performing an RTSA with a latissimus dorsi and teres major tendon transfer provides patients with an ER strength comparable to 50% of the strength of the contralateral shoulder. After the intervention, the patients present a clinically relevant and statistically significant clinical and functional improvement. The transferred musculature (latissimus dorsi and teres major) adapts to its new function and remains functional over time. There is found a relationship between the EMG results with the clinical and functional results of the operated shoulder.

Date of Award	19 Oct 2020
Original language	Spanish
Supervisor	Enric Caceres Palou (Director), Joan Nardi Vilardaga (Director), José Maria Mora Guix (Director) & Joan Minguell Moñart (Director)