Scapular Dyskinesis Test

Original Editor - User Name
Top Contributors - Uchechukwu Chukwuemeka and Vidya Acharya

Purpose

Scapular dyskinesis test (SDT) was developed by McClure in 2009 to assess dyskinesis of the scapular in overhead throwing athletes. The SDT was in a quest to develop an alternative to Kibler's 4-type classification for Scapular dyskinesia

scapular

Technique

Before the test commences, male client is requested to remove their shirts to see the posterior thorax, while female volunteers wear halter tops. In standing, the patient holds two dumbbells of 1.4kg if the patient weighs less than 68.1kg or 2.3kg if the patient weighs ≥68.1kg and is instructed to do 3 repetitions of bilateral flexion followed by 3 repeats of bilateral abduction in the frontal plane with straight elbows.

The examiner stands at the back of the patient during the movement and records the presence or absence of winging and/or dysrhythmia in scapular movement.

Scapular dyskinesis test yes/no classification is a variation on SDT. Using a metronome of 60 beats per minute, the client was instructed to execute 5 successive repetitions of bilateral, active, and weighted 120º shoulder flexion, followed by abduction using dumbbells adjusted to their body weight, following the procedure of McClure et al.

Scapular movement

"Yes" implies the presence of asymmetric shoulders. this is depicted by shoulder movement abnormalities termed

1. Dysrhythmia: seen as scapula protraction or premature or excessive elevation, non-smooth motion during arm elevation or lowering, or rapid downward rotation during arm lowering
2. Winging: the medial border or inferior angle of the scapula is posteriorly displaced from the posterior thorax.

"No" implies the presence of symmetric shoulders. During the first 30º to 60º of shoulder elevation, both scapulae remain stable and move minimally. Scapular rotation is smooth and continuous, moving upward during elevation and downward during humeral lowering. There's no sign of winging.

Evidence

Reliability

The intra- and inter-rater values for professionals were κ=0.92 with 95% confidence interval (CI) of 0.91-0.93 and 0.85 with 95% CI of 0.84-0.87), respectively, while students had κ=0.77 (95% CI, 0.75-0.78) and K-α=0.63 (95% CI, 0.58-0.67).

In a group of patients with subacromial impingement, the intra-rater agreement was 88% and 96% respectively for two raters. The Kappa value for interrater comparison was 0.59, with an 86% agreement rate.

Validity

A study by Tate et al. on overhead sports athletes discovered disparities between normal and visible dyskinesis groups. Participants with dyskinesis had lower scapular upward rotation (P,.001), clavicular elevation (P,.001), and more clavicular protraction (P,.044). There was no significant difference in shoulder symptoms between typical and apparent dyskinesis participants (odds ratio 5 0.79, 95% confidence range 5 0.33, 1.89).