Myofascial Pain Syndrome Due to Trigger Points

1 International Rehabilitation Medicine Association Myofascial Pain Syndrome Due to Trigger Points David G. Simons, IRMA Monograph Series Number 1 November 1987. INTERNATIONAL REHABILITATION MEDICINE ASSOCIATION. President Tyrone M. Reyes, Santo Tomas University Hospital Espana Street Manila, Philippines Past President Honorary Secretary Herman J. Flax, , Martin Grabois, 153 Cruz Street IRMA Administrative Office Apartment 2A Baylor College of Medicine San Juan, Puerto Rico 00901 1333 Moursund Avenue, Rm. A221. Houston, Texas 77030, USA. For additional copies, contact: GEBAUER COMPANY. 9410 St. Catherine Avenue Cleveland, Ohio 44104. Telephone Toll Free 1- 800-321-9348. 2. Myofascial PAIN Syndrome DUE TO Trigger Points . By David G. Simons, Monograph Series Number 1 of the International Rehabilitation Medicine Association in cooperation with Gebauer Company 4 INTRODUCTION 21 Supinator 4 DEFINITIONS 21 Extensores Digitorum and Carpi Radialis 4 INCIDENCE 21 Flexores Digitorum 21 Interossei of Hand 5 PATHOPHYSIOLOGY 23 TRUNK AND BACK PAIN.

2 5 SENSITIZATION OF NERVES AT THE 23 Pectoralis Major and Minor Trigger POINT 23 Serratus Anterior 5 REFERRED PAIN 23 Serratus Posterior Superior 6 PALPABLE BAND 23 Quadratus Lumborum 6 Shortened Sarcomeres 25 Thoracolumbar Paraspinal Muscles 8 Local Twitch Response 25 Abdominal Muscles 8 METABOLIC DISTRESS 25 LOWER EXTREMITY PAIN. Experimental Evidence Value 25 Gluteus Maximus CD CD 00. of Stretch Weakness and 25 Gluteus Medius Fatiguability 25 Gluteus Minimus DIAGNOSIS 27 Piriformis Adductores Longus O CD CD. HISTORY AND PAIN PATTERNS 27 and Brevis Quadriceps Femoris EXAMINATION 27. 10 LABORATORY FINDINGS 27 Biceps Femoris 27 Gastrocnemius 10 DIFFERENTIAL DIAGNOSIS 27 Soleus 11 FIBROSITIS/FIBROMYALGIA 29 Tibialis Anterior 14 ARTICULAR DYSFUNCTION 29 Peroneus Longus and Brevis 14 COMMON PAIN DIAGNOSES 29 Extensores Digitorum and Hallucis Longus 29 Interossei of the Foot 15 TREATMENT 29 PATIENT EDUCATION.

3 15 STRETCH AND SPRAY 30 OTHER STRETCH TECHNIQUES. 15 HEAD AND NECK PAIN 30 Post-isometric Relaxation 17 Upper and Lower Trapezius 30 Ischemic Compression 17 Sternocleidomastoid 30 Massage 17 Masseter and Temporalis 30 INJECTION AND STRETCH. 17 Lateral Pterygoid 31 PERPETUATING FACTORS. 17 Splenii 31 Mechanical Perpetuating Factors 17 Posterior Cervical Muscles 31 Anatomic variations 19 Suboccipital Muscles 31 Seated postural stress 19 SHOULDER AND UPPER EXTREMITY PAIN 31 Standing postural stress 19 Scaleni 31 Vocational stress 19 Levator Scapulae 33 Systemic Perpetuating Factors 19 Deltoid 33 Enzyme dysfunction 19 Infraspinatus 34 Metabolic and endocrine dysfunction 19 Supraspinatus 35 Chronic infection and infestation 19 Latissimus Dorsi 35 Posttraumatic hyperirritability Syndrome 21 Subscapularis 36 Psychological stress 21 Biceps Brachii 21 Brachialis 36 PROGNOSIS.

4 21 Triceps Brachii REPRINTED FROM: . Simons DG: Myofascial pain Syndrome due to Trigger Points , Chapter 45. Rehabilitation Medicine edited by Joseph Goodgold. Mosby Co., St. Louis, 1988 (pp. 686-723). 3. Through the years many different terms have been used INTRODUCTION to describe the specific Myofascial pain syndromes gen- This monograph will interest anyone who sees patients erated by TPs in muscles throughout the body. Previous complaining of the remarkably common Myofascial pain literature has been extensively reviewed for muscle pain 105 93. that originates in muscle. Pain and tenderness are char- syndromes by Simons and for fibrositis by Reynolds. acteristically referred from Myofascial Trigger Points (TPs) Confusion developed over the past century because suc- that are located in muscle remote from the site of the pain.

5 Cessive authors recognized different, often overlapping, This is confusing to the patient and misleading to the prac- aspects of pain due to Myofascial TPs and sometimes titioner. Despite its cryptic origin, referred pain from TPs included features of other conditions. Many authors used general terms applicable to the whole body, such as fibro- can be devastatingly severe. Fortunately, pain due to myo- sitis (which has accrued multiple meanings through the fascial TPs can be identifiable by careful history and skill- 93. years), fibromyalgia, 144. muscular rheumatism (used in ful physical examination; it is quickly responsive to 80. Europe for nearly a century), nonarticular rheumatism, 24. physical medical management in the absence of serious myogeloses (muscle gelling), 5463.

6 Muskelharten (muscle perpetuating factors. hardenings) in Germany, interstitial myofibrositis in 40. We all owe Janet G. Travell, an enormous debt of America, myalgia or myalgic spots in England, and 88. gratitude for her life-long dedication to our understanding osteochrondrosis in R u s s i a . 134. of Myofascial TPs. The recent surge of research interest Other authors used terms applicable to one region of in the elucidation of muscle pain syndromes is now the body without noting its muscular origin or its common- reducing the confusion and doubts surrounding the ality with other parts of the body. Examples 16 include: occip- pathophysiology of TPs. Many of these studies are con- ital neuralgia, tendinitis, tennis elbow, chest wall sidered here. Syndrome , 3. scapulocostal Syndrome , 78.

7 Lumbago, 56 69. ' and 125. Skeletal muscle is the largest organ of the body. It sciatica. Each of these terms may be used to identify at makes up nearly half of body weight. Muscles are the least two conditions, one of which is often MPS due to motors of the body. They work with and against the ubiq- TPs. uitous spring of gravity. Together with the cartilage, liga- ments, and intervertebral discs, they serve as the body's INCIDENCE. mechanical shock absorbers. Each one of the approxi- A meaningful interpretation of incidence must distin- mately 500 skeletal muscles is subject to acute and guish between active TPs that cause pain, either at rest or chronic strain. Each muscle can develop Myofascial TPs in relation to muscular activity, and latent TPs. A latent TP. and has its own characteristic pattern of referred 1 TT 1 ^4.

8 133,134 may show all the diagnostic features of an active TP. except that it causes pain only when the TP is examined Acute cases of a single-muscle Myofascial pain syn- by palpation. drome (MPS) can often be treated readily and effectively when the specific muscle harboring the TP responsible for Latent TPs afflict nearly half the population by early the pain is promptly recognized. Prompt resolution of an adulthood. Among 100 male and 100 female 19 year-old 120. acute single-muscle MPS prevents the needless persis- asymptomatic Air Force recruits, Sola and associates tence of disabling pain. Perpetuating factors can increase found focal tenderness in shoulder-girdle muscles indica- irritability of muscles, leading to the propagation of TPs tive of latent TPs in 54% of the women and 45% of the and increasing the distribution and severity of pain.

9 This men. Pain referred from the TP to its reference zone was progression51leads, in time, to the complex disaster, demonstrable in 5% of these subjects. chronic pain. Recent reports from chronic pain treatment centers showed that Myofascial syndromes were the cause of pain DEFINITIONS in over half of the patients. Among 283 consecutive admis- A Myofascial TP is defined as "a hyperirritable spot, sions to a comprehensive pain center, the primary organic usually within a taut band of skeletal muscle or in the diagnosis30of Myofascial syndromes was assigned in 85%. muscle's fascia, that is painful on compression and that of cases. A neurosurgeon and a physiatrist made this can give rise to characteristic referred pain, tenderness, diagnosis independently, based upon physical examina- 113133.

10 And autonomic phenomena."* tion for soft tissue 35. findings as described by Travell. In another study, the diagnosis was tabulated for 296. The term Myofascial pain Syndrome is used here either patients referred to a dental clinic for chronic head and with a specific or a collective meaning. A single-muscle neck pain of at least 6 months duration. In 164 ( ) of MPS refers to the signs and symptoms caused by active these patients, the primary diagnosis was MPS due to TPs in one specific muscle. Generically, MPS as used in active TPs. The pain of another 21%35was ascribed to dis- the title, refers to the diagnosis and the signs and symp- ease of the temporomandibular joint. toms associated with one or many single-muscle myofa- scial pain syndromes due to TPs. Acute Myofascial pain syndromes due to TPs are rela- tively common in general medical practice.