Summary

The relationship between preoperative clinical scores and shoulder kinematics parameters was explored in 102 patients with rotator cuff tears. Moderate to weak correlations were found between clinical scores (SPADI, OSS) and kinematic parameters (ROM, Peaks, NDJ). The findings suggest the need for a multidimensional and complementary approach to managing patients with rotator cuff diseases.

Abstract

Background

Rotator cuff tears (RCT) are a significant cause of shoulder pain and disability. In clinical practice, assessing a patient's rotator cuff health status generally includes multiple questionnaire-based clinical scales. Optoelectronic motion capture systems (OMC), currently considered the gold standard, can be used to assess shoulder 3D kinematics quantitatively. Identifying new, hitherto unexplored relationships between kinematic parameters and clinical scores may help provide new insights into the management of patients with RCTs.
AIMS
This study investigated the relationships between the most commonly used clinical scores for evaluating patients with RCT and objective kinematic measures retrieved by an OMC.

Methods

In this cross-sectional study, 102 patients (mean age 61±24 years; 50 males and 52 females) scheduled for arthroscopic rotator cuff tear were consecutively recruited between March 2022, and December 2023. For all the patients, clinical scores (ASES, VAS, SPADI, OSS, SF-36) and kinematic parameters (range of motion – ROM, peaks, and normalized dimensionless jers - NDJ) were retrieved preoperatively. We evaluated shoulder kinematics using a stereophotogrammetric system and described the relative motion of the humerus with respect to the thorax (humerothoracic joint angles). Each patient performed four bilateral upper limb movements (flexion-extension, scaption, abduction-adduction, external rotation with shoulder adducted and elbow flexed at 90°) to the maximum range they could achieve without pain condition and at a comfortable and self-selected speed. The Spearman correlation test was performed to highlight any correlation between kinematic parameters and clinical scores at baseline.

Results

The results revealed moderate to weak correlations between some kinematic variables and clinical scales, varying by the kinematic variable type, the task performed, and the specific clinical scale. A significant correlation was found between the SPADI score and Peaks during flexion (ρ = -0.485, p =<0.001) and abduction (ρ = -0.493, p <0.001). Another significant correlation was found between the OSS score and ROM in flexion (ρ = -0.428, p <0.001) and in abduction (ρ = -0.415, p <0.001); moreover, a significant correlation was found between the OSS and peaks in flexion (ρ = -0.403, p<0.001) and in abduction (ρ = -0.407, p<0.001). The study further investigated the previously unexplored correlation between smoothness and clinical scores, revealing a poor correlation (p-value<0.05) between SPADI score and NDJ during scaption (ρ = -0.205, p <0.001).

Discussion

This study emphasizes the importance of a multidimensional approach to managing patients with RCTs, highlighting the complementary role of clinical scores and quantitative shoulder kinematic assessments. Despite the established relevance of clinical scores in evaluating shoulder function and pain, the study identifies a discrepancy between these evaluations and 3D shoulder kinematics performed with an OMC, suggesting the need for complementary tools to evaluate a patient with rotator cuff diseases comprehensively.

Acknowledgement: Funded by the European Union - Next Generation EU - NRRP M6C2 - Investment 2.1 Enhancement and strengthening of biomedical research in the NHS (Project no. PNRR-MAD-2022-12376080 - CUP: F83C22002450001).