Shock Wave Applications in Musculoskeletal Disorders E-Book

Jan Dirk Rompe

• Herausgeber: Thieme
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 152

Veröffentlichungsjahr: 2002

Beschreibung

Shock wave therapy is the revolutionary new non-surgical method of treating orthopedic and musculoskeletal disorders. This succient text is the first English-language publication to present both the positive benefits and limitations of this innovative modality, providing clear and concise information on treating a variety of orthopedic disorders. You will find full coverage of shock wave therapy for treating tendonitis, plantar fascitis, tennis elbow, and more orthopedic disorders where other non-surgical procedures have failed. All orthopedists, physical therapists, chiropractors, and podiatrists will enhance their practice by learning this valuable procedure.

Leseprobe

Shock Wave Applicationsin Musculoskeletal Disorders

Jan-Dirk Rompe, M.D.

Associate ProfessorDepartment of OrthopedicsJohannes Gutenberg UniversitySchool of MedicineMainz, Germany

82 illustrations17 tables

ThiemeStuttgart · New York

Library of Congress Cataloging-in-Publication Data is available from the publisher

Important Note: Medicine is an ever-changing science undergoing continual development. Research and clinical experience are continually expanding our knowledge, in particular our knowledge of proper treatment and drug therapy. Insofar as this book mentions any dosage or application, readers may rest assured that the authors, editors, and publishers have made every effort to ensure that such references are in accordance with the state of knowledge at the time of production of the book.

Nevertheless this does not involve, imply, or express any guarantee or responsibility on the part of the publishers in respect of any dosage instructions and forms of application stated in the book. Every user is requested to examine carefully the manufacturers’ leaflets accompanying each drug and to check, if necessary in consultation with a physician or specialist, whether the dosage schedules mentioned therein or the contraindications stated by the manufacturers differ from the statements made in the present book. Such examination is particularly important with drugs that are either rarely used or have been newly released on the market. Every dosage schedule or every form of application used is entirely at the user’s own risk and responsibility. The authors and publishers request every user to report to the publishers any discrepancies or inaccuracies noticed.

Cover drawing by Martina Berge, Erbach

Any reference to or mention of manufacturers or specific brand names should not be interpreted as an endorsement or advertisement for any company or product.

Some of the product names, patents, and registered designs referred to in this book are in fact registered trademarks or proprietary names even though specific reference to this fact is not always made in the text. Therefore, the appearance of a name without designation as proprietary is not to be construed as a representation by the publisher that it is in the public domain.

This book, including all parts thereof, is legally protected by copyright. Any use, exploitation, or commercialization outside the narrow limits set by copyright legislation, without the publisher’s consent, is illegal and liable to prosecution. This applies in particular to photostat reproduction, copying, preparation of microfilms, and electronic data processing and storage.

© 2002 Georg Thieme Verlag, Rüdigerstraße 14,D-70469 Stuttgart, GermanyThieme, 333 Seventh Avenue,New York, NY 10001, USA.

Typesetting by Mitterweger & Partner, Plankstadt

Printed in Germany by Gulde Druck, Tübingen

ISBN 3-13-130121-X (GTV)ISBN 1-58890-079-7 (TNY)                                                         1 2 3 4 5

ToMy father, Professor Gerhard Rompe,on the occasion of his 70th birthday.He has stimulated my orthopedicand scientific thinking for decades.

ToMy orthopedic mentors at theJohannes Gutenberg UniversitySchool of Medicine, and particularlyto Professor Jochen Heine whointroduced me to the intriguingworld of orthopedic shock wavetherapy.My present colleagues at theDepartment of Orthopedics whohave generously referred to meinteresting shoulder, elbow, and heelproblems throughout the years.All orthopedic surgeons throughoutthe world who have shared theirinteresting cases with me, so thatsome strides might be made in thediagnosis and non-invasivetreatment of these often neglectedpatients.My colleague and friend, LowellWeil Sr. who encouraged me towrite down our experiences inEnglish and share them withphysicans in Anglo-Americancountries.And my wife and our children whounderstand and support me in myendeavors.

Foreword

For more than 20 years extracorporeal shock wave lithotripsy has been the standard tool for dealing with calculi in the kidney and in the ureter. Today, surgical therapy plays only a minor role in the treatment of this disease. About a decade ago, extracorporeal shock wave application (ESWA) was transferred from urology to other medical fields, including gastroenterology and orthopedics.

The aim of this book is to assess, from a scientific point of view, past efforts in experimental research and clinical application of shock waves related to chronic musculoskeletal disorders, and to point out future fields of interest.

Only recently have prospective randomized studies been released concerning effective treatment protocols for patients suffering from chronic painful heel, tennis elbow, and calcifying tendinitis of the shoulder. The author presents his own extraordinary experience, discussing the advantages and disadvantages of various concepts, thus giving the reader extensive information about possibilities and limitations of shock wave application (SWA) presently available.

The animal experiments presented in this book clearly demonstrate the possible damaging effects of shock waves on tendons and on peripheral nerves and point out to the reader the close relationship between physical parameters and tissue reaction.

I consider it important that the author addresses problems related to SWA for musculoskeletal disorders, while simultaneously pointing to the beneficial effects of this new, noninvasive procedure.

This book will form the scientific basis for restrictive indications, for medical quality assessment, and for familiarizing doctors with an innovative treatment concept.

Mainz, December 2001

Prof. Jochen Heine, MDDirectorDepartment of OrthopedicsJohannes Gutenberg UniversitySchool of MedicineMainz, Germany

Preface

Plantar fasciitis is one of the most common conditions presenting to foot and ankle specialists. Although the condition is usually responsive to conservative and nonoperative care, recalcitrant plantar fasciitis occurs in 10–20 % of the patients treated.

Until recently, plantar fasciotomy, with or without spur resection or release of nerve entrapments, has been the only option for this ever-increasing patient population.

For 6 years we have patiently awaited the opportunity to evaluate this new modality of extracorporeal shock wave therapy (ESWT). As one would expect, skepticism and cynicism prevailed until our first 10 patients rendered favorable responses within days of treatment. Lowell Weil, Jr., one of my associates, embraced this technology and we traveled to Naples, Italy, in June of 2000 to attend the 2nd International Meeting of the International Musculoskeletal Shock Wave Association. We were thoroughly impressed with the honesty and attempt at providing results according to evidence-based medicine.

Upon meeting Jan Rompe, we found an individual who was energetic, bright, and honest.

With the recent application and ongoing clinical trials of ESWT occurring in the United States, I encouraged Dr. Rompe to write a book in English as a work of reference for those of us who are monolingual.

As an author of more than 12 papers on ESWT, Jan Rompe was able to write this text, which is a combination of a current literature review and the results of clinical trials at his medical institution, on virtually every application of musculoskeletal ESWT. With more than 200 relevant references, this book will be a “must read” for those wishing to learn more and apply this exciting and new technology.

Chicago, December 2001

Lowell Scott Weil, Sr., DPMEditor-in-ChiefWeil Foot & Ankle InstituteDes Plaines, IL, USA

Acknowledgments

A heartfelt thank-you to Lowell Weil Sr. for giving me the courage to write a book in a foreign language, for reviewing this work, and for his invaluable help in handling many details with Thieme Publishers.

It is with grateful appreciation that I acknowledge the skill and dedication of Erwin Scholtz and Barbara Hof-Barocke in rendering the medical illustrations. They gave the art for this book high priority, and I am appreciative of their devotion to this work.

A note of appreciation is also given to Dr. Clifford Bergman who served as an invaluable interface with Thieme Publishers in taking care of numerous details that led to the completion of this book. In the shortest time possible he initiated publication of this work.

Contents

1 Physical Characteristics of Shock Waves

Physics

Acoustic Properties of Media

Cavitation

Shock Wave Generation

2 Dose-Dependent Effects of Extracorporeal Shock Waves on Rabbit Achilles Tendon

Introduction

Materials and Methods

Results

Sonography

Histopathology

Discussion

3 Dose-Dependent Effects of Extracorporeal Shock Waves on Rabbit Sciatic Nerve

Introduction

Materials and Methods

Results

Discussion

4 Dose-Dependent Effects of Extracorporeal Shock Waves in a Fibular-Defect Model in Rabbits

Introduction

Materials and Methods

Results

Discussion

5 Extracorporeal Shock Wave Application in the Treatment of Chronic Plantar Fasciitis

Introduction

Materials and Methods

Inclusion Criteria

Exclusion Criteria

Randomization

Group I

Group II

Method of Treatment

Method of Evaluation

Primary Outcome Measure

Secondary Outcome Measures

Statistics

Results

Follow-up

Primary Outcome Measure

Secondary Outcome Measures

Pressure Pain

Night Pain and Resting Pain

Walking

Radiographic Evaluations

Complications

Additional Treatment between 3 and 6 Months

Additional Treatment during the 5 Years

Discussion

Conclusion

6 Extracorporeal Shock Wave Application in the Treatment of Chronic Tennis Elbow

Introduction

Materials and Methods

Inclusion Criteria

Exclusion Criteria

Group I

Group II

Method of Treatment

Method of Evaluation

Statistics

Results

Additional Treatment

Complications

Discussion

Conclusion

7 Extracorporeal Shock Wave Application in the Treatment of Chronic Calcifying Tendinitis of the Shoulder

Introduction

Materials and Methods

Inclusion Criteria

Exclusion Criteria

Group I

Group II

Method of Treatment

Method of Evaluation

Radiological Evaluation

Statistics

Results

Rate of Follow-up

Clinical Outcome in the University of California Los Angeles Score

Radiological Outcome

Radiomorphological Features and Clinical Outcome

Hospital Stay

Absence from Work

Complications

Subjective Rating

8 Extracorporeal Shock Wave Application in the Treatment of Nonunions

Introduction

Materials and Methods

Inclusion Criteria

Exclusion Criteria

Method of Treatment

Method of Evaluation

Results

Discussion

References

Index

1 Physical Characteristics of Shock Waves

Physics

Shock waves are the result of the phenomenon that creates intense changes in pressure, as evidenced in lightning or supersonic aircraft. These huge changes in pressure produce strong waves of compressive and tensile forces that can travel through any elastic medium such as air, water, or certain solid substances.

A shock wave is defined as an acoustic wave, at the front of which pressure rises from the ambient value to its maximum within a few nanoseconds (Krause 1997, Ogden et al. 2001, Ueberle 1997, Wess et al. 1997). Typical characteristics are high peak-pressure amplitudes (500 bar) withrisetimesoflessthan10nanoseconds, a short lifecycle (10 ms), and a frequency spectrum ranging from the audible to the far end of the ultrasonic scale (16Hz–20MHz).

As shown in Figure 1.1, the pressure rapidly rises from ambient values to the peak value, the so-called peak positive pressure (P+), then drops exponentially to zero and negative values within microseconds. This pressure versus time curve describes the transient shock wave at one specific point-like location of the pressure field.

The pressure disturbance is transient and propagates in three-dimensional space. To obtain spatial information on the total shock wave field, numerous samples of the shock waves have to be collected. Three-dimensional plots of the P+-values may then give an impression of the pressure field distribution.

The pulse energy needs to be focused in order to be applied where treatment is needed. According to the spatial distribution of the pressure, the focus of the shock wave is defined as the location of the maximum peak positive acoustic pressure P+. In relation to P+ as the reference, the −6 dB focal extent in the x, y, and z-directions is physically defined by the −6dB contour around the focus location. In other words, the focal dimensions are determined by half of the peak positive pressure (P+/2) contour (Fig. 1.2). This typical “cigarshaped” focal extent of the device usually covers an area of about 50 mm in the axis of the shock wave axis, with a diameter of 4.0 mm perpendicular to the shock wave axis (focal width). Concentrating the focus of the shock wave field therefore is of paramount importance for successful therapy (Hagelauer et al. 2001).

Fig. 1.1 A typical shock wave is characterized by a positive pressure step (P+) having an extremely short rise time (tr), followed by an exponential decay to ambient pressure. It typically lasts several hundred nanoseconds.

Fig. 1.2 Three-dimensional pressure distribution within the x, y, and z plane.

Many physical effects depend on the energy involved. Thus, shock wave energy is deemed to be an important parameter for clinical application, too. The energy of the shock wave field is calculated by taking the time integral over the pressure/time function (Fig. 1.1) at each particular location of the pressure field, for example, in the focal area:

The concentrated shock wave energy per area is another important parameter. Physicists use the term “energy flux density” to illustrate the fact that the shock wave energy flows through an area with perpendicular orientation to the direction of propagation. It is a measure of the energy per square area that is being released by the sonic pulse at a specific point:

Acoustic Properties of Media

where Z1 and Z2 are the impedances of medium 1and of medium 2, respectively. The reflected energy is calculated from the square of the amplitude.

If the impedance of the second medium is lower than the first, the polarity of the reflected pressure is reversed, i.e., positive pressure becomes negative pressure or underpressure.

This is especially the case at interfaces between tissue and air, for example, at the interface of lung tissue. Because nearly all the energy is reflected at this interface, the delicate alveolar tissue is unable to resist the mechanical forces of the shock wave and will disrupt.

Fig. 1.3 If concretions are impacted in the surrounding tissue, the so-called Hopkins effect leads to destruction beginning at the rear side of the concretion because the tensile strength is exceeded due to the underpressure.

The effect of pressure reversal also occurs at another interface: When the shock wave transmitted into a calcific deposit or into bone hits the posterior border of this medium, a portion of the shock wave is reflected into the deposit or into the bone as negative pressure, because the muscle tissue at the back of the deposit or the bone has a lower impedance than the deposit or the bone. This reflected wave is then superimposed with the later overpressure portion of the incident wave so that particularly strong tensile forces act on the rear of the deposit or the bone (Hopkins effect) (Fig. 1.3).

Cavitation

Cavitation is defined as the occurrence of gasfilled hollow bodies in a liquid medium. Stable cavitation bubbles are in equilibrium when the vapor pressure inside the bubble is equal to the external pressure of the liquid.

When a shock wave hits a cavitation bubble, the increased external pressure causes the bubble to shrink, whereby the latter absorbs part of the sonic energy. If the excitant energies and consequent forces are strong enough, the bubble collapses, thereby releasing part of the energy stored in the bubble to the liquid medium as a secondary shock wave. The radius of a cavitation bubble is about 500 micrometer in water. The bubble collapses about 2–3 microseconds after being hit by the shock wave. The resulting collapse pressure of the secondary wave is about one-tenth of the initial shock wave pressure and exists for about 30 nanoseconds. Thus, the sonic energy released by the collapsing bubble is less by a factor of 1000 than that of the excitant shock wave.

Due to the one-sided impact of the excitant shock wave the bubble collapses asymmetrically, sending out a jet of water. This jet can reach speeds of 100–800 m/s, sufficient, for example, to perforate aluminum membranes or plastics. The needle-shaped hemorrhages (petechiae) on the skin after shock wave therapy (SWT) are attributed to this cavitation effect.

Fig. 1.4 Gas-filled bubbles are first compressed by the positive peak pressure of the shock wave, then expand dramatically due to the underpressure component of the shock wave.

The underpressure part of the initial shock wave leads to a contrary effect: microbubbles grow during underpressure. They may reach a stable size which can be three orders of magnitude larger than the nucleus and can exist for several hundred microseconds. If these bubbles are hit by a following shock wave, once again a collapse with cavitation effects is produced (Fig. 1.4).

Shock Wave Generation

Extracorporeal shock waves used in medicine today are emitted as a result of electromagnetic, piezoelectric, or electrohydraulic generation. All studies presented in this book were done using a source of electromagnetic shock waves.

Electromagnetic systems utilize an electromagnetic coil and an opposing metal membrane. A high current impulse is released through the coil to generate a strong magnetic field, which induces a high current in the opposing membrane, accelerating the metal membrane away from the coil to the 100,000-fold of gravity, thus producing an acoustic impulse in surrounding water. The impulse is focused by an acoustic lens to direct the shock wave energy to the target tissue. The lens controls the focus size and the amount of energy produced within the target (Fig. 1.5).

Piezoelectric systems are characterized by mounting piezoelectric crystals to a spherical surface. When a high voltage is applied to the crystals they immediately contract and expand, thus generating a pressure pulse in surrounding water. The pulse is focused by means of the geometrical shape of the sphere (Fig. 1.6).

Electrohydraulic systems incorporate an electrode, submerged in a water-filled housing comprised of an ellipsoid and a patient interface. The electrohydraulic generator initiates the shock wave by an electrical spark produced between the tips of the electrode. Vaporization of the water molecules between the tips of the electrode produce an explosion, thus creating a spherical shock wave. The wave is then reflected from the inside wall of a metal ellipsoid to create a focal point of shock wave energy in the target tissue. The size and shape of the ellipsoid control the focal size and the amount of energy within the target (Fig. 1.7).

Fig. 1.5 Electromagnetic shock wave generator.

Fig. 1.6 Piezoelectric shock wave generator.

Fig. 1.7