ARTIGO DO MÊS (8/2009)

Radiographic analysis of commonly prescribed scapular exercises
Cote, M. P., Gomlinski, G., Tracy, J., Mazzocca, A. D.
J Shoulder Elbow Surg (2009) 18, 311-316
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=19128986

HYPOTHESIS: The performance of scapular exercises in the context of a clinical model of fatigue will result in superior migration of the humeral head and alterations in shoulder kinematics on radiographic analysis.

MATERIALS AND METHODS: Six healthy male volunteers underwent a series of radiographs before and immediately following two scapular exercises. To reproduce a practice setting a clinical model of muscle fatigue was utilized. Radiographs were taken at various degrees of elevation. Glenohumeral angle (GA), scapulothoracic angle (SA), and the position of the humeral head on the glenoid (excursion) were measured on each radiograph. Two-tailed paired sample t-test were used to compare pre-fatigue to post fatigue measures.

RESULTS: Following fatigue there was a significant increase in excursion at 45, 90, and 135 degrees of elevation indicating superior migration of the humeral head. There was an increase in SA from 0 to 45 degrees and a decrease in GA from 45 to 90 degrees of elevation. From 90 to 135 degrees an increase in GA was observed.

DISCUSSION: The amount of superior migration of the humeral head observed following exercise was consistent with previously reported amounts of superior migration in patients with subacromial impingement. The alterations that occurred in shoulder kinematics following exercise may have resulted from parascapular muscle fatigue as well as rotator cuff muscle insufficiency.

CONCLUSION: In the context of a clinical model of fatigue, these scapular exercises resulted in superior migration of the humeral head and alterations in shoulder kinematics on radiographic analysis in healthy subjects.

LEVEL OF EVIDENCE: Basic science study.

" the largest amount of superior migration of the humeral head post fatigue was observed as the arm elevated to 45. The function of the rotator cuff muscles during elevation is to center the humeral head on the glenoid. Fatigue of these muscles has been shown to produce superior migration of the humeral head in healthy volunteers. This effect has been attributed to alteration of the deltoid-rotator cuff force couple.

IDEIA - CHAVE

"Functionally, insufficient rotator cuff musculature either through exercise induced fatigue or pathologic deficiency disrupts the force couple, creating superior migration of the humeral head on the glenoid."

IMPLICAÇÃO CLINICA:

Todos os exercícios recomendados e seguidos no programa de recuperação funcional após lesões no ombro (p.ex. sindrome de conflito sub-acromial, tendinopatia da coifa dos rotadores, instabiliadde multidirecional) se não forem devidamente orientados e analisados promovem movimentos compensatórios da omoplata/clavicula, com alteração do padrão de recrutamento dos músculos envolvidos contribuindo para manter a disfunção e os sintomas por longos períodos.

DEVE SER DADO ÊNFASE NA (RE)APRENDIZAGEM DOS PADRÕES NORMAIS DE MOVIMENTO E NÃO NO FORTALECIMENTO ANALÍTICO E MERAMENTE MECÂNICO

Raul Oliveira, Fisioterapeuta