Abstract
Introduction: The Constant Score Functional Assessment (CS) is now the standard method of assessing shoulder disability in Europe. Previous studies have indicated that the CS values associated with a full-thickness rotator cuff tear (RCT) are lower than for normal shoulders. This study was designed to investigate which parameters of the CS were most influenced by the presence of a RCT. As ultrasonograpy has now been shown to have a high accuracy for diagnosing full-thickness RCTs it was used to establish the diagnosis.
Methods: 28 patients attending the Shoulder Clinic were invited to take part in this study for which Local Ethics Committee approval had been obtained. The majority of patients had a painful shoulder on at least one side. All patients had a CS carried out with the “Strength” measurement made in 3 ways – 1) maximum force using a fixed spring balance – FSB(max); 2) maximum force using a commercial myometer – M(max); 3) mean force from 2 to 4 seconds using a commcercial Myometer – M(mean). The CS was measured with no knowledge of the patient’s history or diagnosis and blinded to the state of the rotator cuff. The patients were then assessed using ultrasonograpy of the shoulder (Diasus with an 8–16MHz head) to establish the presence of a full-thickness RCT.
Results: The CS Values for the left and right shoulders have been analysed separately.
The results have also been analysed for each part of the Constant Score – Pain, Activities of Daily Living, Range of Movement and Strength and these will be presented.
Discussion: It was anticipated that subjects with a RCT would be found to be weaker and have a reduced CS in an affected shoulder. This was found to be the case for the left shoulder but not for the right. The reasons for this will be discussed. The abnormally low CS for the normal right shoulders (Group 1) will also be explored.
Conclusion: The CS may be a valuable method of identifying those patients with a RCT. This study indicates that a more careful evaluation of “Strength” measurements still needs to be undertaken.
Correspondence should be addressed to Carlos Widgerowitz, Honorary Secretary BORS, Division of Surgery and Oncology, Section of Orthopaedic and Trauma Surgery, Ninewells Hospital and Medical School, Tort Centre, Dundee DD1 9SY, Scotland.
