Background and Purpose. As direct access evolves, physical therapists will increasingly encounter patients with pathology that might have an underlying systemic origin. The purpose of this case report is to describe the diagnostic process that led a patient's physical therapist to recognize signs and symptoms of dermatomyositis. Case Description. The patient was an 18-year-old woman who was referred for physical therapy by her primary care physician on 3 occasions with 3 separate musculoskeletal diagnoses. During the third episode, the physical therapist recognized signs and symptoms that could be indicative of dermatologic disease and referred the patient to a dermatologist. Outcomes. A rheumatologist diagnosed the patient's condition as dermatomyositis and referred her for physical therapy. The physical therapy plan of care focused on strengthening and stretching, with an emphasis on a home exercise program. The Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) indicated that the patient continually made functional improvements over an 18-month period. Discussion. Although diagnosis of diseases such as inflammatory myopathies is not within a physical therapist's scope of practice, this case demonstrates the role a physical therapist can play in recognition of underlying systemic pathology by using the diagnostic process.
One of the many changes in health care is the shifting boundary of the practice of physical therapy in outpatient orthopedic clinics.1 Direct access and primary care physical therapy are currently topics of great interest. Although primary care physical therapy continues to develop in the area of differential diagnosis, diagnosis of systemic disorders such as inflammatory diseases is not within a physical therapist's scope of practice. Rather, physical therapists should recognize when a referral is appropriate and be able to recognize and communicate a list of clinical findings of concern that might indicate underlying systemic pathophysiology.2
Many clinicians believe that the majority of clinical diagnoses are established after taking an extensive history.3 The initial data collected can serve as a foundation for hypothesis development, whereas the rest of the examination data will confirm or refute these hypotheses.4,5 Frequently, when a patient has a systemic disease, data collection will entail diagnostic measures (eg, radiographs, blood analyses) that require tests that are outside of the scope of physical therapy practice. Physical therapists are increasingly sensitive to the musculoskeletal manifestations of systemic disease for specific body regions and are asking questions in the history taking to clarify the origin of the symptoms (eg, presence of a fever, digestive problems, sleep disturbances, nausea, onset of pain, aggravating factors, course of the complaint).6 Physical therapists, therefore, need to recognize signs and symptoms that may be indicative of disease that is outside the scope of physical therapy practice and warrants a referral to the appropriate medical care provider.
With direct access to physical therapy services, the chance is increased that a patient may have what appears to be a musculoskeletal disorder with an underlying cause that is outside the scope of physical therapy practice. One such disorder is idiopathic inflammatory dermatomyositis. Although dermatomyositis is uncommon (0.5–8.4 cases per million7), patients with this disorder may seek physical therapy with clinical findings that suggest a musculoskeletal disorder. Primary idiopathic dermatomyositis is among the 5 categories of idiopathic inflammatory myopathies8 and among many autoimmune disorders that have the same clinical, pathological, and serological findings.9 Distinct immunopathological changes, muscle histopathology with signs of inflammation, fibrosis, and loss of muscle fiber culminating in muscle atrophy occur with idiopathic inflammatory myopathies, which eventually affects the patient's strength (the maximum force a muscle can generate) and function.10 Progressive weakness of the proximal muscles is a common complaint in 53% to 96% of patients with dermatomyositis.9,11 Peak incidence of dermatomyositis typically occurs around the age of 50 years, but it can begin at any age.12 Women are twice as likely to contract the disease as men, and African Americans have an increased risk.12,13
Proximal muscle weakness is a dominant feature of dermatomyositis, although cutaneous skin lesions may be the first symptom recognized.14,15 The cutaneous manifestations include a heliotrope rash (Fig. 1) and Gottron papules located over bony prominences, most commonly the metacarpophalangeal (MCP) and proximal interphalangeal (IP) joints.16–18 Cutaneous manifestations affecting the scalp are often characteristic of dermatomyositis.17 The many possible cutaneous findings that can occur with dermatomyositis are listed in Table 1. Kasteler and Callen17 demonstrated that scalp involvement is frequently overlooked in dermatomyositis. They noted that 14 of 17 patients with dermatomyositis seen over a 5-year period had scalp involvement. Five of these patients were misdiagnosed with scalp psoriasis or seborrheic dermatitis prior to being diagnosed with dermatomyositis. Kasteler and Callen concluded that scalp involvement with dermatomyositis is not uncommon and can be present as a diffuse erythemal dermatosis, at times with nonscarring alopecia.
In addition to the skin and muscle involvement, a number of systemic manifestations can be present, including dysphagia (50% of patients), cardiac abnormalities (40% of patients), pulmonary involvement (50% of patients), and subcutaneous calcifications.19 It also has been reported that a high percentage of patients with dermatomyositis will eventually develop some form of cancer, most commonly associated with malignancies of the lung, gastrointestinal tract, and ovaries.20 Airio and colleagues20 reviewed the medical records of 71 patients with dermatomyositis and found that 34 (48%) had cancer, which was an incidence 6 times greater than that of the general population. These patients represent what Bohan and Peter21 have described as specific of people with dermatomyositis.
Physical therapists are in a position to encounter patients with pathology that might be manifested as musculoskeletal symptoms but who have an underlying immunological pathophysiology. The purposes of this case report are: (1) to describe a patient who had what was initially believed to be a musculoskeletal impairment but was later determined to be an immunological disorder and (2) to describe the physical therapy management and long-term functional outcomes of the patient.
“JB” was an 18-year-old European-American woman who was a high school athlete. She said she had good general physical health and worked out with the soccer team for approximately 2 hours each day. She did not smoke and reported a history of moderate alcohol consumption. Recreational activities included playing soccer and participating in track and field events, and she had a part-time job as a waitress at a local restaurant. She earned mostly A's or B's in school and was visiting colleges in pursuit of higher education. JB signed an informed consent statement that had been approved by the Institutional Review Board at Notre Dame College, Manchester, NH.
The medical questionnaire revealed that she had no personal or familial history of systemic disease. At the time of JB's first episode of physical therapy care a review of systems as described in the Guide to Physical Therapist Practice,22 including the cardiovascular (heart rate, pulse), pulmonary (respiratory rate), neuromuscular (balance, coordination), and integumentary (color, integrity, temperature) systems, did not reveal any abnormalities. She reported no allergies and was not taking any medications at the time of her initial examination.
JB's primary care physician first referred her for physical therapy with a diagnosis of a right hamstring muscle strain (Fig. 2). Her chief complaint was of a deep achy right posterior thigh pain when attempting to run, which measured 8 out of 10 on the numeric (0–10) pain scale (NPS), with 0 representing “no pain” and 10 representing “worst pain possible.”23 Data obtained with the NPS have demonstrated high test-retest reliability (intraclass correlation coefficient [ICC]=.96)24 and a strong correlation (r=.85) to data collected with a visual analog scale.25 She said that the injury occurred 3 days prior when an opposing player tripped her during a soccer game. Her pain at rest fluctuated from 0 to 2 on the NPS. The pain limited her ability to play soccer, but she reported no other functional deficits at that time and was able to continue working as a waitress. JB reported no previous history of lower-extremity injury and stated that she was in good physical health and exercised regularly. A systems review indicated no problems. She was not taking any medications, and no radiographs or other diagnostic tests had been ordered at that time. Her goal was to return to playing soccer at full capacity without symptoms.
Static standing examination revealed a forward head carriage, shoulders anterior relative to the coronal midplane bilaterally (greater on the right side than on the left side), right ilium higher than the left ilium, right lower extremity held in slight lateral (external) rotation, and slight calcaneal valgus and mild subtalar pronation bilaterally.
Observational gait analysis indicated a slight decrease in stride length and a minimal decrease in stance time on the right lower extremity. Although reliability assessment of the data collected during the static examination and gait observation had not been performed prior to this case report, one clinician collected all data in an attempt to reduce measurement error. JB was able to perform a full squat without pain, but she experienced pain (4 on the NPS) when returning to a standing position from the squat position. She also had pain when going up and down stairs (4 on the NPS) leading with the right foot. JB was able to perform a single-leg stance without pain, but could balance for only 18 seconds on the right lower extremity and for 43 seconds on the left lower extremity. She was unable to rise up on her right toes without an increase in pain (3 on the NPS).
Active range of motion (ROM) of the lumbar spine, right hip, knee and ankle, and toes was within normal limits and pain-free. Passive ROM also was full and pain-free with the exception of right straight leg raising (SLR), which reproduced her symptoms at 70 degrees of knee extension. Cervical flexion combined with the SLR did not alter her symptoms. The 90–90 passive SLR test26 was positive for symptom reproduction on the right side, and she lacked 48 degrees of knee extension. She lacked 26 degrees of knee extension and was pain-free on the left side. Intratester reliability of goniometric knee extension measurements is high (r=.91).27 She had positive Ober and Thomas tests,26 suggesting tight tensor fasciae latae and hip flexor muscles bilaterally; however, neither caused pain. Joint mobility testing of the hip, including long axis distraction, lateral distraction, and inferior glide of the femoral head,26 revealed that accessory motions of the right femur equal to those of the left femur.
Neurological examination, including muscle stretch reflexes and sensory and myotome testing, and neurovascular examination (femoral and dorsal pedal pulse) revealed no abnormalities in either lower extremity. Neurodynamic tests, including the slump test, were performed to assess the mechanical sensitivity of neurological tissues28 and were found to be negative on both the left and right sides. Manual muscle testing (MMT) revealed the gluteus medius muscles to be 4+/5 and the right hamstring muscles (semimembranosus, semitendinosus, and biceps femoris) to be 4+/5 bilaterally. Manual muscle testing of the right hamstring muscles exacerbated her symptoms. The left hamstring muscles measured 5/5. Depending on the muscle tested, data collected with MMT have demonstrated moderate to good intratester reliability (r=.63–.98).29
Soft tissue palpation revealed exquisite tenderness of the right biceps femoris muscle, characterized by the patient pulling away and grimacing with minimal contact. Palpation of bony landmarks revealed an elevated anterior superior iliac spine (ASIS) on the right and a lower posterior superior iliac spine (PSIS). JB also had a positive Gillet test26 on the right, signifying right sacroiliac joint hypomobility. However, it should be noted that the intratester reliability of hypomobility as determined by the Gillet test is poor (kappa=.00).30
Following the history, the clinician's working hypothesis was that the patient had a right hamstring muscle strain. This hypothesis was further supported by the data collected during the tests and measures portion of the examination and by the fact that JB's symptoms were mechanically reproducible and the resisted isometric test to the right hamstring muscle was strong but painful, which according to Cyriax and Cyriax31 suggests a minor lesion of a muscle or tendon. The only other impairment recognized during the examination was a positive Gillet test on the right side. However, data suggest that the Gillet test may not be useful in identifying innominate rotations.32 The examination findings supported the hypothesis that JB had a right hamstring muscle strain but was otherwise in good health.
JB was treated during 5 visits over a 3-week period with pulsed ultrasound, soft tissue mobilization, stretching and functional strengthening exercises, and cryotherapy. Despite the questionable validity of the Gillet test, muscle energy techniques, considering the minimal risk involved,33 were directed at a right posteriorly rotated innominate bone.
At the end of the 5 visits, JB's pain had completely resolved, and she was able to run for 30 minutes without pain. At the time of discharge, 3 weeks after the initial evaluation (Fig. 2), she had returned to playing soccer at full capacity.
About 2 weeks after being discharged from the first episode of physical therapy, JB's primary care physician referred her for physical therapy again, this time with a diagnosis of left cervical strain. Her primary complaint was left-sided neck pain that was exacerbated by carrying trays at work and by studying or reading for prolonged periods. She described her pain as a deep achy sensation and rated the pain during work as 6 on the NPS. She said that the pain was negligible at rest (rated 1 on the NPS); however, she reported occasional periods of disturbed sleep. JB stated that the pain started 7 days earlier as an insidious onset, but was most likely related to a busy day at work. She was not taking any medications. When questioned if she had experienced any disorders involving the gastrointestinal, cardiovascular, genitourinary, or neurological systems since her first episode, she denied any changes in health status.
Observation of static posture indicated a forward head carriage and shoulders anterior relative to the coronal midplane and medially (internally) rotated bilaterally. Her left clavicle and shoulder were elevated. She held her head in a slight position of side bending to the left.
Visual estimation of active cervical ROM revealed limitations of side bending to the right (50% limitation), side bending to the left (25% limitation), rotation to the left and right (50% limitation), and flexion (25% limitation). The between-tester reliability for measurements obtained with visual estimation of cervical active ROM has been demonstrated to be between poor and good (ICC=.42–.82) depending on the motion measured.34 JB complained of an increase in symptoms (5 on the NPS) with side bending to the right and rotation to the left. Passive ROM revealed limitations that corresponded to the active limitations listed. Passive accessory intervertebral assessment35 demonstrated a hypomobility of segments T1-T4 in a posteroanterior direction. These same segments also had restricted extension. However, measurements of passive intervertebral movement has been shown to have poor reliability (kappa=−.06 to −.49).36 Passive muscle flexibility testing performed according to the procedure described by Evjenth and Hamberg37 revealed decreased tissue extensibility of the left upper trapezius and levator muscles, and the testing recreated JB's symptoms. Analysis of the reliability of passive cervical movements has been inconclusive.36
Neurological and neurovascular examinations were negative throughout both upper extremities. Upper-limb neurodynamic test positions (I, II, and III28) were negative. Manual muscle testing revealed that the upper trapezius muscle on the right was painful and measured 4+/5. Bilateral middle and lower trapezius muscles had MMT grades of 4+/5 and 4/5, respectively. Palpation revealed tenderness of the upper trapezius muscle on the left, which she reported was similar to her symptoms.
Following the history, the clinician's working hypothesis was a left upper trapezius muscle strain. This hypothesis was further supported by the findings that the patient's symptoms were mechanically reproducible and the resisted isometric test to the left upper trapezius muscle was strong but painful, which according to Cyriax and Cyriax31 suggests a minor lesion of a muscle or tendon.
JB was treated during 6 sessions over a 3-week period with soft tissue mobilization; stretching of the upper trapezius, levator scapulae, and scalene muscles; and cold modalities. Neuromuscular re-education with tactile facilitation (slow tapping) of the lower and middle trapezius muscles was utilized to enhance kinesthesia, proprioception, and appropriate movement patterns.38 Mobilization of the first through fourth thoracic vertebrae was performed according to the procedure described by Maitland39 (grades III–IV) in a posteroanterior direction.
At the end of the 6 sessions, JB was able to work as a waitress (including carrying a tray with her left upper extremity) without pain.
Eleven days after discharge from the second episode of physical therapy, JB's primary care physician referred her for physical therapy with a diagnosis of a right ankle sprain (Fig. 2). She reported that while climbing a “fire lookout tower,” she forcefully inverted her right ankle. She stated that she experienced immediate pain in the lateral aspect of her right ankle and within 30 minutes noted moderate swelling. Her primary care physician prescribed naproxen. She was again unable to play soccer because of pain (8 on the NPS) with weight-bearing activities. At rest, her pain decreased to 4 or 5 on the NPS. JB again reported no history of systemic disease and no health changes since the time of her last physical therapy visit; however, she did report occasions of malaise and muscle weakness.
Observation of static standing revealed calcaneal valgus bilaterally (greater on the right side than on the left side), she held her right knee in slight flexion, and she had slight lateral rotation at the right hip. Gait deviations included short stance time and lack of ankle plantar flexion on the right side.
She had localized swelling and ecchymosis of the lateral aspect of her right ankle. JB held her ankle in a position of slight dorsiflexion and eversion. Her anterior talofibular ligament was extremely tender to palpation, and she reported that this reproduced her symptoms. Active ROM measurements were 28 degrees for plantar flexion, 8 degrees for dorsiflexion, 12 degrees for inversion, and 15 degrees for eversion. Goniometric measurements of ankle ROM for plantar flexion and dorsiflexion have demonstrated good intratester reliability (ICC=.86–.90), but intratester reliability has been reported to be poor for inversion and eversion measurements (ICC=.22–.30).40 She reported that both plantar flexion and inversion increased her symptoms to 9 on the NPS. Dorsal pedal pulse was the same as the contralateral side. Neurodynamic testing was not performed because of the irritability of the condition. An anterior drawer test of the ankle was found to be positive on the right side.26
Manual muscle testing revealed considerable strength deficits of both lower extremities. The MMT grades were 4/5 for the gluteus maximus and quadriceps femoris muscles and 4/5 for the gluteus medius, iliopsoas, and hamstring muscles. Flexibility restrictions were found in the hamstring muscles bilaterally. The right knee lacked 62 degrees and left knee lacked 53 degrees of knee flexion during the 90–90 passive SLR test. The Thomas test and rectus femoris muscle contracture test were positive bilaterally, signifying flexibility restrictions of the hip flexor and rectus femoris muscles.26
The patient's initial report of malaise and muscle weakness raised some concerns that her impairments might not solely be musculoskeletal in nature. The considerable changes in hamstring muscle length demonstrated by the 90–90 passive SLR test (a reduction of knee extension by 27° on the left side and 14° on the right side) since the first episode of physical therapy (10 weeks earlier) also raised some concerns about the nature of the disorder. Ellis and Stowe41 found that the maximum error for intratester measurements was between 1% and 5%. The changes in JB's hamstring muscle length exceeded the reported standard measurement of error for knee extension, increasing by 29% on the right side and 50% on the left side. In addition, reductions in strength were recorded in the hamstring muscles (4+ on the right side compared with 4, 5 on left side compared with 4), quadriceps femoris muscles (5 bilaterally compared with 4 bilaterally), and gluteus medius muscles (4+ on the right side compared with 4, 5 on the left side compared with 4) since the time of the second episode of physical therapy (10 weeks earlier). These findings facilitated MMT of the scapulothoracic muscles, which also demonstrated reductions in strength of the middle trapezius muscles (4+ bilaterally compared with 4−) and the lower trapezius muscles (4 bilaterally compared with 3+) since the time of the second episode of physical therapy (5 weeks earlier).
Although the measurements may not have exceeded the likely measurement error of one full grade as found by Iddings et al42 in a group of patients with poliomyelitis, the progressive flexibility deficits and the strength deficits in all tested muscles further suggested the possibility of an underlying pathology. In a young, athletic woman, the progressive deficits in muscle length and strength in a relatively short period (5–10 weeks) led to a review of systems as described in the Guide to Physical Therapist Practice,22 including the cardiovascular (heart rate, pulse), pulmonary (respiratory rate), neuromuscular (balance, coordination), and integumentary (color, integrity, temperature) systems.
Visual inspection of the integumentary system (performed with the patient in a medical gown to allow visualization of all extremities and the trunk) revealed a mild rash over the dorsum of her IP and MCP joints (Fig. 3), as well as at her hairline. Although she reported no change in health status while giving her history, she had neglected to report that this “rash” had appeared a few weeks earlier. She stated that she thought it was just dry skin and thought nothing of it. She said she had not recently had a fever. A review of the cardiovascular (heart rate, pulse), pulmonary (respiratory rate), and neuromuscular (balance, coordination) systems did not reveal any abnormalities.
Referral to Other Practitioner
Because of the cutaneous rash and the history of proximal muscle weakness and fatigue, we hypothesized that JB might have an undiagnosed disease and referred her to a dermatologist. The dermatology visit was scheduled for 10 days after the initial examination. Although we believed that JB required referral to a dermatologist, we also believed that she had physical impairments that would benefit from physical therapy intervention; therefore, we addressed her edema, pain, and stability of the right ankle prior to her visit with the dermatologist. Physical therapy management initially (visit 1) focused on edema and pain reduction. Once pain decreased to the level where she could perform pain-free isometric exercises, they were instituted (visit 2). At the time of her third visit, she reported that her pain had resolved, and she was able to tolerate concentric strength exercises for the ankle musculature. On the fourth (final) visit, she had maintained her pain-free status, and treatment was progressed to include eccentric strengthening exercises and single-leg stance for proprioceptive and kinesthetic training. Although her sprained ankle recovered over 4 visits, she did not return to sports, and it was becoming clear that she might have an underlying disease, given the added symptoms of fatigue, increasing weakness and flexibility restrictions, and rash.
After her visit with the dermatologist and having diagnostic tests (laboratory and muscle biopsies), the patient contacted her primary therapist (JAC) via telephone to discuss the results of the tests. JB had been diagnosed preliminarily with dermatomyositis based on a creatine phosphokinase (CK) level of 487 U/L (normal female levels=10–79 U/L). She was referred to a rheumatologist, who confirmed the diagnosis with a biopsy of the right quadriceps femoris muscle and prescribed prednisone (10 mg daily) and methotrexate (15 mg per week). Her rheumatologist suggested that she begin physical therapy for the purpose of general strengthening and flexibility.
Three weeks after referral to the dermatologist, JB's rheumatologist referred her for physical therapy (Fig. 2) with the objective of developing a general stretching and strengthening regimen. JB completed a Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) questionnaire to quantify functional levels. The reliability and validity of data obtained with the SF-36 questionnaire as a general health measure have not been investigated in patients with dermatomyositis; however, the reliability and validity of data obtained with the SF-36 questionnaire have been well documented in patients with other rheumatological disorders (rheumatoid arthritis and psoriatic arthritis).43–45 Ruta et al45 reported test-retest ICCs of .93, .78, and .76, respectively, for the physical functioning, mental health, and pain scales of the SF-36 questionnaire in patients with rheumatoid arthritis. The construct validity of the data collected with the SF-36 scales has been determined (r=−.12 to −.89) by comparing scores obtained with the American College of Rheumatology disease activity measures.45 Data obtained with the SF-36 questionnaire have been highly correlated with the severity of rheumatoid arthritis and moderately correlated with disease activity in patients with psoriatic arthritis.43,44
Several studies10,46–48 have investigated the effects of therapeutic exercise in patients with dermatomyositis. These studies have shown that both resistive and nonresistive exercises can result in improved oxygen uptake,47,48 strength,46–48 and function.10,47,48 The benefits of exercise in patients with dermatomyositis could not be directly generalized to JB because these studies included subjects with both polymyositis and dermatomyositis. Regardless, there are limited data49,50 to support the hypothesis that exercise is detrimental in this patient population when CK levels are elevated. However, the data suggesting that exercise is detrimental are exceeded by the strength of the evidence in support of resisted, nonresisted, and aerobic exercises in this patient population.10,46–48 Considering the reported benefits of exercise in patients with dermatomyositis and given limited information on the systemic status of our patient and the fact that she had responded to therapy in the recent past and was otherwise young and active, we decided to continue the exercise program, progressing slowly under close monitoring. Therefore, management strategies focused on developing a therapeutic exercise regimen to address impairments identified during the examination. According to the Guide to Physical Therapist Practice,22 80% of patients with dermatomyositis should reach expected outcomes within 3 to 36 visits. A purpose of the physical therapy plan of care was to establish an independent therapeutic exercise program that would maximize strength and function despite the possibility of disease progression. In a pilot study, Alexanderson et al51 demonstrated that patients with both dermatomyositis and polymyositis had improved function (measured with the SF-36 questionnaire) following a 12-week home exercise program consisting of strength exercises for quadriceps femoris, hamstring, and abdominal muscles with “careful” stretching exercises.
JB was instructed twice weekly over the course of 6 weeks in a resistive and nonresistive exercise program in addition to aerobic activities on the stationary bicycle and upper-body ergometer. Specific exercises were developed to address impairments in passive muscle flexibility and strength as indicated. Specific physical therapy interventions prescribed during each session are shown in Table 2. Exercise progression was based on subject response and clinical experience of the physical therapist who continually monitored her for signs of excessive fatigue (diaphoresis, shortness of breath). JB also was instructed to report any time she experienced a fever, which could be indicative of an exacerbation. She was asked prior to each treatment session if she had any adverse effects from the previous physical therapy session or her home exercise program. If she had not, the therapeutic exercise program was mildly increased to include 1 or 2 additional minutes of aerobic activities, a few more repetitions (1–2) of a specific exercise, or the addition of a new exercise. In addition, blood work taken 6 weeks after the dermatomyositis diagnosis revealed a considerable reduction in CK levels (142 U/L), indicating that even with the therapeutic exercise regimen, the acute nature of the disorder was diminishing. In inflammatory muscle disease, CK levels are an indication of muscle damage in most patients. Diminishing levels suggest that the muscle damage is slowing as the inflammatory process comes under control.8
After being discharged to an independent program (Fig. 2), JB continued to perform her exercise program independently in the clinic 3 times a week. This continued for 8 months, at which time she left for college. She again completed the SF-36 questionnaire. JB was instructed to maintain her current level of therapeutic exercise while at school. She returned to our clinic the following year to update us on her status. She reported consistency with her home exercise program and again completed the SF-36 questionnaire for an 18-month follow-up. The SF-36 questionnaire results are shown in Table 3.
At the time of her 18-month follow-up, JB reported that she had returned to all functional activities with the exception of athletics. She reported that this was not necessarily related to the dermatomyositis, as she devoted the majority of her time and effort to her studies. She was involved in a workout regimen at a local health club and was able to walk around campus (up to 30 minutes between classes) without pain or discomfort. However, she reported that she would fatigue more quickly than when she was in high school. She was unable to speculate whether this was related to the dermatomyositis or was simply a result of a more sedentary lifestyle since entering college. She had also returned to her job as a waitress during the summer months.
Idiopathic inflammatory myopathies are divided into 5 groups: (1) primary idiopathic polymyositis, (2) primary idiopathic dermatomyositis, (3) dermatomyositis or polymyositis associated with neoplasia, (4) childhood dermatomyositis (or polymyositis) associated with vasculitis, and (5) polymyositis or dermatomyositis with associated collagen vascular disease.8 JB's condition was diagnosed as primary idiopathic dermatomyositis. As defined in the literature, her diagnosis was not arrived at because of a single predominant symptom but evolved over time and involved the elimination of other diseases through physical therapy (musculoskeletal disorders), dermatology (skin diseases), and rheumatology (connective tissue disease screen). By the time of her medical diagnosis, JB had positive findings of Gottron papules on both the dorsal IP and MCP joints (symmetrical, lacy, and pink in appearance to red, raised, macular areas) and elevated CK levels, which confirmed the diagnosis. Diagnosis of dermatomyositis is complicated, and frequently the disorder goes unrecognized in the initial stages. Given the signs and symptoms of the disease, the initial health care encounters may be with a variety of clinicians, including dermatologists, internists, and family medicine practitioners, as well as physical therapists. Dermatomyositis is a progressive connective tissue disorder characterized by symmetrical weakness of the limbs and the proximal stabilizing muscles and anterior neck flexors, which progresses over weeks to months, with or without dysphagia or respiratory involvement.11,21 The differential diagnosis for dermatomyositis can be challenging and includes, but is not limited to, lichen planus, polymorphous light eruption, seborrheic dermatitis, systemic lupus erythematosus, psoriasis, contact dermatitis, and atopic dermatitis.52
Muscle biopsy is the “gold standard” for diagnosing dermatomyositis, but the diagnosis also can be made on the basis of serological and electromyographic data.12,53 When the muscle membrane degenerates during the disease process, muscle enzymes are released from the muscle fibers.19 Creatine phosphokinase is the muscle enzyme that is most present in the disease and can be elevated up to 50 times over normal levels.12,19 Due to the degenerating muscle membrane in people with dermatomyositis, electromyographic data will demonstrate fibrillations and short-acting firing potentials of very low amplitude.12 Once a diagnosis of dermatomyositis is made, the initial treatment includes pharmacological management and rest. Glucocorticoids (prednisone at 1 mg/kg/d for 4–8 weeks) are the standard first-line drugs used to treat this disorder. As powerful immunosuppresants, they rapidly reduce inflammation and give muscle a chance to restore itself in the early stages of the disease.13,19,54 As an anti-inflammatory drug, prednisone decreases the synthesis of prostaglandins and leukotrienes.55 Prolonged corticosteroid use can result in catabolic effects on muscle (and ligaments, tendons, bone, and skin) and weakness resulting in altered CK levels, which can mimic a worsening dermatomyositis.52,55
The cornerstone of pharmacological therapy is frequently medications such as azathioprine (1–2 mg/kg/d) and methotrexate (once weekly doses of 25–50 mg intramuscularly, 5–15 mg orally, or 15–50 mg intravenously).13,54 Methotrexate has both strong anti-inflammatory and immunosuppressive modes of actions. Methotrexate inhibits the proliferation of rapidly replicating cells (monocytes, lymphocytes) that contribute to the immune response.55 Long-term side effects of methotrexate include pulmonary dysfunction, liver dysfunction, hematological disorders, and hair loss.55 The mechanism of action of azathioprine is not fully understood, but it is believed that it impairs synthesis of DNA and RNA precursors.55 Azathioprine is relatively toxic and may result in various side effects, including fever, chills, sore throat, loss of appetite, nausea, and vomiting.55 Although these drugs have undergone multiple clinical trials for other neoplastic and immunologic dysfunctions, their effectiveness for the treatment of dermatomyositis has not been documented.
Nonpharmacological management typically includes physical therapy and should be considered a component of the overall management of patients with dermatomyositis.7 Although it has been reported that reduction in muscle strength is typically the symptom that most impairs quality of life,15 some debate exists as to the appropriateness of therapeutic exercises during the acute stage for fear of aggravating the inflammatory process.9,14 However, no data exist to support the contention that exercise will exacerbate the inflammatory response.51 Although re-establishment of muscle strength through a physical therapy program is the proposed long-term intervention for dermatomyositis,10 the progressive nature of the disease suggests that the patient's current physical status (deterioration or recovery) should dictate the balance between physical therapy intervention and rest. In addition, because CK is an indicator of the acuity of the disease,53 CK levels should be used as a guide to the intensity of a physical therapy program. A patient's body temperature also should be monitored because a fever may be indicative of an exacerbation.8
Studies have supported the hypothesis that exercise is beneficial in the treatment of patients with inflammatory diseases of muscle. Escalante et al46 investigated the effects of 6 exercise sessions (3 resistive and 3 nonresistive) in one patient using CK levels as the indicator of disease acuity. The patient did not exhibit an increase in muscle strength; however, the patient's performance of activities of daily living improved. During the study, CK increased, and the authors speculated that the increased CK was related to attempts to taper the dose of prednisone. Heikkila and colleagues10 also demonstrated that short-term (3-week) intensive therapeutic exercise programs designed by a physical therapist resulted in improvements in function in 22 patients diagnosed with myositis (4 with dermatomyositis). During the study, CK serum levels were monitored and remained stable, indicating that the therapeutic exercise did not result in an increase in muscle inflammation. Because these authors' patients had dermatomyositis, polymyositis, and inclusion body myositis, however, it is difficult to generalize data and change practice patterns with individual patients based on the results.
Wiesinger and colleagues47 investigated the effects of a 6-week program of aerobic and stretching exercises on 14 participants (9 with dermatomyositis and 5 with polymyositis), all of whom had disease duration greater than 6 months. Results demonstrated improvement in both muscle strength and oxygen uptake (with no rise in inflammatory activity as indicated by CK levels) when compared with a control group. In a follow-up study, Wiesinger and colleagues48 investigated the effects of the same exercise program carried out over a 6-month period with 8 patients (6 with dermatomyositis and 2 with polymyositis). The findings were similar to those of the first study in that both isometric muscle strength and maximum oxygen uptake increased, with no change in serum CK levels. The patients' performance of activities of daily living also improved. The results were consistent with the quantified improvements in function as demonstrated by increases in SF-36 questionnaire scores and the continued reduction in CK levels, as exhibited with JB. Again, however, including both patients with dermatomyositis and patients with polymyositis makes it difficult to draw conclusions about specific patient populations based on their results. Although these studies give us insight about the effects of exercise when treating patients with inflammatory muscle disease in general, they are of limited usefulness in understanding the specific response of individuals with dermatomyositis.
The process of diagnosis is not the exclusive domain of any one profession.56 The difference between diagnoses made by physical therapists and those made by physicians is not the process itself but the phenomena that are being observed and classified.57 Physical therapy diagnoses are focused on classifying dysfunction rather than the disease itself and, therefore, are different from a medical diagnosis.58 This case report demonstrates the identification of systemic disease using a hypothesis-oriented algorithm as described by Echternach and Rothstein.5 The clinical decision-making scheme guides the clinician through the evaluation, hypothesis generation, and reassessment to determine if the working hypothesis is accurate. During the first 2 episodes of care with this patient, working hypotheses were tested through the implementation of interventions. At the time of the third episode, however, “red flags” (malaise, proximal muscle weakness, and skin rash) were obvious, which required a provisional hypothesis and referral to a dermatologist. Recognizing possible signs and symptoms and referring the patient to the appropriate medical professional could be the first step in the diagnostic process.
The patient in this case report initially had mechanically reproducible symptoms indicating a musculoskeletal disorder. With continued episodes of care, however, other symptoms indicated that an underlying systemic disease might be present. Due to the nature of the physical therapy examination (cardiopulmonary, integumentary, musculoskeletal, and neuromuscular systems review) and the amount of time spent with patients, physical therapists may have an advantage in recognizing signs and symptoms that may be nonmusculoskeletal in nature. As direct access and primary care physical therapy continue, the demand to recognize common signs and symptoms of systemic disease will become increasingly important.
The scientific evaluation of therapeutic management strategies for patients with dermatomyositis is limited. We attribute this, in large part, to the rarity of this condition, which affects the ability of researchers to carry out large randomized controlled trials. We encourage physical therapists to seek as much data (CK levels, medication changes) as possible from the referral source during the course of physical therapy to assist in guiding appropriate management strategies. This case report illustrates the role that physical therapists can have in the diagnosis of dermatomyositis.
Both authors provided concept/idea/project design, writing, and consultation (including review of manuscript before submission). Dr Cleland provided data collection and analysis, project management, patient, and facilities/equipment.
- Received February 7, 2003.
- Accepted May 26, 2003.
- Physical Therapy