Spinal Control: The Rehabilitation of Back Pain

State of the art and science

Paul W. Hodges, Jacek Cholewicki, Jaap H van Dieen, Paul W. Hodges, Jacek Cholewicki, Jaap H van Dieen

• Publisher: Churchill Livingstone
• Year: 2013
• Print ISBN: 9780702043567
• eBook ISBN: 9780702054549
• Topic: Medicina
• Subtopic: Medicina alternativa e complementare

For the first time, international scientific and clinical leaders have collaborated to present this exclusive book which integrates state-of-the art engineering concepts of spine control into clinically relevant approaches for the rehabilitation of low back pain. Spinal Control identifies the scope of the problem around motor control of the spine and pelvis while defining key terminology and methods as well as placing experimental findings into context.Spinal Control also includes contributions that put forward different sides of critical arguments (e.g. whether or not to focus on training the deep muscles of the trunk) and then bring these arguments together to help both scientists and clinicians better understand the convergences and divergences within this field.On the one hand, this book seeks to resolve many of the issues that are debated in existing literature, while on the other, its contributing opinion leaders present current best practice on how to study the questions facing the field of spine control, and then go on to outline the key directions for future research.Spinal Control – the only expert resource which provides a trusted, consensus approach to low back pain rehabilitation for both clinicians and scientists alike!- Covers the most important issues in spine control research- Illustrates the clinical relevance of research and how this is or can be applied in clinical practice- Edited and written by world leading experts, contributing first class content on different aspects of spine control- Chapters that bring together the expertise of these world leaders on topics such as neuromotor mechanisms of spine control, proprioception, subgrouping in back pain and modelling spine stability- An extensive and illustrated clinical consensus chapter that brings together the philosophies of clinical opinion leaders for the first time

Chapter 1

Introduction

convergence and divergence of opinions on spinal control

Paul W. Hodges*, Jaap H. van Dieën^† and Jacek Cholewicki^‡, ^*NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury and Health, School of Health and Rehabilitation Sciences, University of Queensland, Brisbane, Queensland, Australia,, ^†MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, Amsterdam, The Netherlands and, ^‡Department of Osteopathic Surgical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, USA

Chapter contents

Models of spine control and experimental approaches

Motor control

Proprioceptive systems

Spinal control as a basis for design of clinical treatments for low back and pelvic pain

Convergence and divergence of opinions in ‘spine control’

References

It is well defended and accepted that control of the spine and pelvis depends on the contribution of active, passive and control systems (Panjabi 1992). In this interpretation of spine physiology, ideal control relies on the appropriate passive support, supplemented with muscle forces that are coordinated by the nervous system. Conversely, changes in any of these systems can lead to less than optimal control and this has formed the basis of a range of rehabilitation strategies that aim to restore control and reduce pain and disability or the potential for further pain or injury. Although the theoretical underpinning is relatively straightforward, there is variable evidence for the many assumptions that underlie the understanding of ‘spine control’ and the way in which it may be modified with pain and/or injury or the manner in which aspects of spine control may be a precursor to development of pain and/or injury. An area of considerable variation in opinion is how this model can be applied to clinical practice for the treatment of people with low back and pelvic pain.

Low back and pelvic pain is a major issue facing the modern world. The economic burden of musculoskeletal pain is second only to cardiovascular disease (Australian Bureau of Statistics 2001) and of that burden, spinal complaints contribute the greatest percentage due to long-term disability. Low back pain (LBP) is the most common chronic pain in Australia (Blyth et al. 2001), and the most common work-related condition in Western society. Recurrence and persistence of symptoms are major issues in LBP and are associated with the majority of its health care and social costs. Persistent LBP is increasing and its prevalence has doubled in the last 14 years (Freburger et al. 2009). Although clinical guidelines promote the view that acute LBP has a favourable prognosis with most people recovered in 6 weeks (Koes et al. 2001), systematic reviews of prospective trials suggest that 73% of people experience at least one recurrence in 12 months of an acute episode, and pain and disability have only recovered by 58% at one month (Pengel et al. 2003). Further recovery is slow (Pengel et al. 2003; Henschke et al. 2009). Identification of modifiable factors associated with LBP is a key objective in the international research agenda. However, reviews of risk factors provide less than encouraging results (Linton 2000; Pincus et al. 2002). Even factors that have been purported to have the strongest relationship to outcome, such as psychosocial aspects of distress (Pincus et al. 2002) and job satisfaction (Linton 2000), can only account for a small proportion of the variability (Linton 2000; Young Casey et al. 2008). There is no evidence for an association between biological factors such as trunk muscle strength or endurance, or range of motion and LBP outcome (Hamberg-van Reenen et al. 2007). However, in clinical practice and many fields of research, it has been proposed that ‘spine control’ is related to low back and pelvic pain and investigation of this promising notion is worthy of a concerted research effort.

There are considerable promising data of changes in spine control as a potential candidate factor underpinning the development and persistence of low back and pelvic pain from cross-sectional studies (Hodges and Richardson 1996; MacDonald et al. 2009) and some longitudinal studies (Cholewicki et al. 2005). Positive outcomes from clinical trials, that have been summarized and subjected to meta-analyses in a number of systematic reviews (Ferreira et al. 2006; Macedo et al. 2009), provide additional strength to the argument that consideration of ‘spine control’ in the management of low back and pelvic pain is worthwhile and promising.

The counter argument is that biological aspects are less important than psychosocial aspects of pain, and that compromised spine control may be present but neither sufficient nor necessary for the perpetuation of pain. Criticism of the biological model of pain has come from a number of sources. For instance, the lack of a one-to-one relationship between indications of structural damage on diagnostic imaging and pain is commonly used as an argument against the importance of mechanical injury in its origin. However, such argumentation could be used similarly to deny the relation between smoking and lung cancer; not every person with lung cancer is or was a smoker, nor does every smoker develop lung cancer. A probabilistic model is more appropriate here and structural abnormalities are strong risk factors for LBP.

Current evidence suggests we cannot reject the contribution of biological issues to development and persistence of pain. The quality of ‘spine control’ which determines the nature and magnitude of loading on spinal structures is likely to be a key factor in this equation. However, within the consideration of spine control there are different interpretations and opinions. There are differing opinions regarding the most appropriate theoretical models to understand the systems; this extends to biomechanical/engineering models, neurophysiological models of control of motor output and sensory input, and clinical models extrapolating from research and clinical practice to formulate effective treatments for back pain. This book aims to provide a state-of-the-art review of the current understanding of these issues, the areas where opinions converge and diverge, and a road map for consideration of how to resolve the critical questions in the field.

Models of spine control and experimental approaches

There are fundamental differences in how people define and model spine control leading to different interpretations of what is optimal. Although early models relied on static methods, more recent approaches propose dynamic models and consideration of systems engineering aimed at understanding the mechanisms by which the spine is controlled to meet the demands of everyday activities. A key issue is that different models rely on different assumptions and lead to different conclusions about the optimal mechanisms for spine control and about the consequences of changes in control for the health of the system and, therefore, lead to different extrapolations from science to clinical practice. The first part of this book (Chapters 2–4) takes a look at the state-of-the-art research in terms of modelling and novel experimental approaches that aim to provide insight into the mechanisms for control of this complex system.

Motor control

Motor control is a term that can be used to refer to all aspects of control of movement. This can extend from the motivation within the frontal and other regions of the brain related to the decision to move, the sensory inputs to the system that provide information of the body segments’ current location and movement, the various levels of the nervous system that integrate inputs and plan outputs (from simple spinal cord mechanisms to complex supraspinal integration and decision making), the motor output to the muscles (the effector organs of the system), and down to the mechanical properties of the tissues (including muscle mechanics and passive tissues that influence joint mechanics) that influence the manner in which motor commands to muscles relate to movement.

There are many views of how consideration of motor control can be applied to the issue of spine control, and how the nervous system meets the challenge to control the spine and pelvis when considered in the context of the entire human body function. Drawing on the developments in modelling of spine biomechanics highlighted in Chapters 2–4, this view of spine control involves not only control of the spine movement and position that is specific to the demands of the task, but also the contribution of the spine to other physiological functions such as breathing and maintaining whole body equilibrium, to name but a few functions that the nervous system must consider concurrently.

Perhaps the most debated aspect of motor control, as it relates to spine control, is how and why motor control is altered in people with pain and injury. Fundamental questions remain unresolved. Are there issues in motor control that can predispose an individual to development of pain and/or injury? Does motor control adapt in response to pain and injury or is this a factor in the persistence and recurrence of pain? Which aspects of motor control are the most critical for low back and pelvic pain, if at all? Which aspects of motor control, if any, should be addressed in patients with low back and pelvic pain? Part 2 of this book (Chapters 5–11) tackles these fundamental issues to provide a comprehensive view of the current state of knowledge.

Proprioceptive systems

Although sensation is a critical element of motor control, there are issues related to sensory function that require specific consideration. Deficits in proprioception have been described for many conditions related to pain and injury in the musculoskeletal system. From deficits in the acuity to detect input (Lee et al. 2010), to changes in the organization of cortical areas associated with sensory function (Flor et al. 1997). A glaring issue in the low back and pelvic pain literature is why do some studies report differences in sensory function between patients with low back pain and healthy control subjects, whereas others do not? This could be explained by many reasons: differences between patient subgroups, differences between specific parameters of sensory function that have been studied, or other methodological issues (e.g. sample size and reliability/validity of measures). Resolution of this issue and other issues (such as the question of which sources of sensory information are used in the control of the spine, and how this is used) requires deeper understanding of sensory function as it relates to the spine and pelvis. Any extrapolation from research to clinical practice necessitates an understanding of the state-of-the-art of this field. This discussion forms the basis of Part 3 (Chapters 12–14).

Spinal control as a basis for design of clinical treatments for low back and pelvic pain

Perhaps the biggest point of apparent divergence of opinion arises when the findings of research and the observations from clinical practice are translated into clinical interventions for the management of low back and pelvic pain. Many clinical programs have been proposed. On the surface, these approaches have often been viewed as divergent and the unique aspects of each are often emphasized to amplify points of difference. But how different are they really? Do they share a common foundation with some specific distinctions based on different interpretations of the literature and clinical observations? Or are they diametrically opposed, mutually exclusive and incapable of being amalgamated into a single broader approach? The debate has often been fuelled by presentation of simplified/reductionist views of an approach to a single element (e.g...

Table of contents

• Cover image
• Title page
• Table of Contents
• Front Matter
• Copyright
• Contributors
• Preface: A meeting of minds on spine control
• Chapter 1. Introduction: convergence and divergence of opinions on spinal control
• Part 1: Models of the spine
• Part 2: Motor control of the spine
• Part 3: Proprioceptive systems
• Part 4: Clinical evidence of control approach
• Part 5: State-of-the-art reviews
• Part 6: State-of-the-art approach to clinical rehabilitation of low back and pelvic pain
• Index