Forward to
"The Science & Art of Musculoskeletal Diagnosis"
from Emeritus Professor Gwenolyn Jull
It is with pleasure that I write the Foreword to this text by Dr Mark Laslett. Mark is a New Zealand physiotherapist of international renown whose career has included work as a clinician, teacher and researcher, a perfect career blend to understand and inform the many components of a health profession. Mark’s clinical and academic work has had an international impact in the field of diagnostics of musculoskeletal disorders, most notably for the sacroiliac joint and low back. His first major research publication in the journal Spine, some 30 years ago, was the seminal publication ‘The reliability of selected pain provocation tests for sacroiliac joint pathology’ doi: 10.1097/00007632-199405310-00009. This was a foundation paper for his lifelong clinical and research interests and work in diagnostics.
The Science and Art of Musculoskeletal Diagnosis is a novel and intriguing text that aims to inform clinicians on the science of diagnostics as it relates to musculoskeletal clinical practice. This can be a complex topic, but the content is presented in a user-friendly and informative way. It will certainly be of interest to clinicians and students who are digesting and interpreting the literature, as well as researchers entering the field of testing psychometric properties of clinical tests.
The first section of the text deals with the “Science of Diagnostics’ which presents and explains many of the properties on which to judge diagnostic accuracy of clinical tests. The text covers, for example, reliability, estimates of sensitivity and specificity, positive and negative predictive values, and likelihood ratios. The description of these properties and relevant statistics can be very dry and unappealing, but Mark is able to present a clear explanation of the property in conversational and clinically relevant language, which I found was a major appeal and strength of this text. The tests themselves, what they measure, how data is collected, and the relevant statistics are presented. The text is supported by numerous illustrations of data and processes, which help clarify many explanations. There is a genuine effort to engage and support the reader, and practical assistance is even provided via links to spreadsheets and Excel workbooks developed by the author. It is an excellent information source that the reader can refer to time and time again.
The second section of the text introduces and discusses the ‘art’ of diagnosis, which presents the clinical context of diagnosis, that is, the process of discovering the source and cause of a patient’s symptoms. I must admit, I like the saying "standing on the shoulders of giants" which is a metaphor meaning that we use the knowledge gained from leaders and trailblazers who have gone before to make progress. In this section, Mark shares his experiences with the giants of the 20th century on whose shoulders he stood and how his interests in musculoskeletal diagnosis were generated and informed. It is a fascinating insight into his personal journey through a physiotherapy career, and the influences of many pioneers of the musculoskeletal field, but particularly from notables such as James Cyriax, Robin McKenzie (clinical diagnosis) and Charles Aprill (anaesthetic blocks in diagnosis). Mark shares his reflections on how James Cyriax developed the foundations of clinical diagnosis of musculoskeletal disorders and the major contribution by Robin McKenzie through his work on the value of sustained end-range loading and repeated movement, and how his initial concepts were the foundations for his future research in diagnostics.
The development of diagnostic criterion standards is discussed and illustrated with copious clinical examples. The clinical examples highlight the complexity of the process but help present it in an understandable way. The principles in determining criterion standards are presented and discussed. As an illustration, the reader gains an excellent overview of the evolution of the use of anaesthetic blocks to find the pain source, with attribution to the clinical enquiry and skills of Dr Charles Aprill. The advantages and pitfalls of injections of anaesthetic in diagnosis are highlighted, as well as the role of clinical skill, which is a vital and sometimes overlooked criterion for any diagnostic procedure, particularly those involving manual skills. The process of measurement of pre- and post-procedure pain intensity is presented, which is required in diagnostic accuracy research. Tools are again provided to assist the clinician and researcher.
Mark reveals himself as a true expert teacher, presenting analogies and stories which clearly illustrate and bring home important messages, as evident in presenting diagnosis as a puzzle to solve. There are salient messages on the need to appreciate the whole clinical picture in any diagnostic decision-making. The chapter on ‘real clinical reasoning’ provides clear and relevant clinical illustrations of the different modes of reasoning in clinical practice. Diagnosis by Subtraction, a concept further developed by the author, is an excellent exposé of clinical reasoning in action to increase the probability of a correct diagnosis. The extensive use of clinical examples brings the science of diagnosis to life. The breadth of his thought is widened with the defence of the historic understanding of cause and effect against post-modernist philosophies.
The third and fourth sections are a goldmine of knowledge and experience. It presents a series of 27 cases managed by the author at some point. First, details are provided of the patient’s presentation, initial examination findings and treatment decisions. Readers are challenged and guided to test and further develop their clinical reasoning skills in diagnostic clinical reasoning, working with each case. Tables to facilitate the process are provided. Second, the diagnostic reasoning for each case is presented, as well as the case notes related to diagnosis and management. This allows the reader to compare their reasoning with that of an expert, a wonderful learning experience. In addition, management of each case is discussed in some detail, which is also a rich source of information.
Mark is to be congratulated on the production of this text. One of its strengths is that it is written and presented in an applied manner rather than the sometimes very mysterious language of statistics. The clinical illustrations throughout bring meaning and clarity to the science of diagnostics. We are rapidly moving into an era where AI is being integrated into healthcare across multiple dimensions, from diagnostics to treatment delivery. I do not think AI could ever produce such a text as this. Readers benefit from a wealth of methodological and clinical information generated from 50 years of personal experience by an expert in the musculoskeletal field.
Gwendolen Jull AO, MPhty, PhD, FACP
Emeritus Professor in Physiotherapy
School of Health and rehabilitation Sciences
The University of Queensland
Australia