Electronic Thesis and Dissertation Repository


Doctor of Philosophy


Health and Rehabilitation Sciences


Dr. Tom Overend

2nd Supervisor

Dr. Bert Chesworth

Joint Supervisor


Shoulder pain is one of the leading causes of referrals to physiotherapy clinics. The annual prevalence of shoulder complaints is about 100 to 160 per 1000 patients in general population. Complexity of shoulder joint, and lack of uniformity of diagnostic labeling commonly used in clinical practice, makes it difficult to make a precise diagnosis. In addition, issues with reliability and validity exist for the shoulder Orthopedic Special Tests (OSTs), making accurate diagnoses challenging.

The primary aim of this thesis was to investigate usefulness of the McKenzie system of Mechanical Diagnosis and Therapy (MDT) in classifying and treating patients with shoulder disorders. This thesis includes three research studies. The first study (chapter 2) is a reliability study suggesting that the McKenzie system of MDT has very good inter-examiner reliability in classifying patients with shoulder pain. The second study (chapter 3) has a specific focus on clinical application of the MDT system in patients with shoulder pain through conducting a prospective longitudinal study. The primary objective of this study was to determine whether patients’ pain and functional response to the McKenzie system of MDT differs by MDT classification category at two and four weeks following the start of MDT treatment. The study results suggest that classifying patients with shoulder pain using the MDT system can impact treatment outcomes and the frequency of discharge. When MDT-trained clinicians match the intervention to a specific MDT classification, the outcome is aligned with the response expectation of the classification. The third study (chapter 4) investigated the relationship between the results of three shoulder OSTs (Hawkins-Kennedy, Speed’s test, and Empty Can) and the McKenzie system of MDT classification to explore the possibility that MDT classification of Derangement adversely affect the consistency of OSTs. The study results suggest that, due to the rapidly changing nature of Derangement classification, there is poorer agreement between the OSTs in patients with Derangement compared to patients with Dysfunction classification. Thus, Derangement may be responsible for reducing the overall agreement of commonly used OSTs. The thesis concludes with a discussion (chapter 5) of next steps towards comprehending usefulness of the MDT system in management of patients with shoulder disorders.