In outpatient physical therapy settings, low back pain (LBP) is a

Transcription

1 Cancer as a Cause of Low Back Pain in a Patient Seen in a Direct Access Physical Therapy Setting Michael D. Ross, PT, DHS, OCS 1 Edmond Bayer, MPT 1 Journal of Orthopaedic & Sports Physical Therapy Study Design: Resident s case problem. Background: This paper describes the clinical course of a patient with low back pain (LBP) and left lower extremity pain and tingling, and how the physical therapist used clinical examination findings and a lack of improvement with conservative measures to initiate further medical evaluation, which resulted in a diagnosis of cancer as the primary cause of the patient s low back and hip pain. Diagnosis: A 45-year-old man with chief complaints of left-sided LBP, left posterior thigh pain, and tingling along the anterolateral aspect of his left lower extremity was initially seen by a physical therapist in a direct access setting. Several components of the patient s history and physical examination were consistent with a mechanical neuromusculoskeletal dysfunction. However, there were signs and symptoms present that may have been suggestive of more serious underlying disease. Specifically, the patient s most intense pain was in the evening and into the night and an atypical pattern of restricted motion at the left hip was noted. Therefore, the physical therapist recommended that the patient schedule an appointment with his physician for medical evaluation. A short-term course of physical therapy treatment was also undertaken to address neuromusculoskeletal impairments. Despite 5 physical therapy visits over the course of a month, while the patient waited for his scheduled physician appointment, the patient s condition gradually worsened. After medical evaluation, the patient was eventually diagnosed with small cell carcinoma of the lung, with metastases to the spine and pelvis. Despite 2 cycles of chemotherapy, the patient succumbed to the cancer 5 months after he was first seen in physical therapy. Discussion: It is important that physical therapists have an understanding of the clinical findings associated with the presence of serious underlying diseases causing LBP, as this information provides guidance as to when communication with the patient s physician is warranted. J Orthop Sports Phys Ther 2005;35: Key Words: carcinoma, diagnostic imaging, lumbar spine In outpatient physical therapy settings, low back pain (LBP) is a common condition for which patients seek treatment. While it is rare that LBP is caused by serious underlying disease, 8,9 this possibility must always be considered. Therefore, along with the physical therapist s role 1 Senior Physical Therapist, Departments of Physical Therapy and Primary Care, David Grant US Air Force Medical Center, Travis Air Force Base, CA. 2 Physical Therapist, Departments of Physical Therapy and Internal Medicine, Kaiser Permanente Medical Center, Vallejo, CA. The opinions expressed herein are those of the authors and do not necessarily reflect the opinions of the Department of Defense, the United States Air Force, or other federal agencies. Address correspondence to Michael D. Ross, 124 Bradley Blvd, Travis AFB, CA michael.ross2@travis.af.mil to conservatively treat mechanical neuromusculoskeletal dysfunction, there is a responsibility to screen for signs and symptoms of serious disease that may warrant physician examination. 2,3 For the purpose of this paper, mechanical dysfunction refers to symptoms that arise from the neuromusculoskeletal system and vary with movement. 27 Determining whether a patient s symptoms are related to mechanical dysfunction or serious underlying disease can be difficult, especially because serious diseases may initially present as mechanical dysfunction. 3 While malignant neoplasms are the most common of these serious underlying diseases which may cause LBP, they comprise less than 1% of LBP episodes. 8 Deyo and Diehl 8 studied 1975 consecutive patients seeking medical care for LBP in a walk-in primary care clinic in a public hospital. They reported that only 13 of these 1975 patients (0.66%) had LBP related to underlying cancer. The 4 clinical findings with the highest positive likelihood ratios for detecting the presence of cancer resulting in LBP were a previous history of cancer, failure to improve with conservative medical treatment during the past month, an age of at least 50 years or older, and unexplained weight loss of more than 4.5 kg in 6 months RESIDENT S CASE PROBLEM Journal of Orthopaedic & Sports Physical Therapy 651

2 TABLE 1. Diagnostic accuracy of clinical findings from the history in patients with cancer causing low back pain (data provided from Deyo and Diehl 8 ). Likelihood ratios (LRs) were calculated from sensitivity and specificity values provided from Deyo and Diehl. 8 Positive LR Negative LR Sensitivity Specificity Previous history of cancer Failure to improve with a month of conservative therapy Age 50 y Unexplained weight loss Duration of pain mo No relief with bed rest Insidious onset of symptoms (Table 1). All of the patients with cancer had at least 1 of these clinical findings, and the absence of all 4 of these clinical findings confidently rules out malignancy. 8 Additionally, no patient who had cancer had both a Westergren erythrocyte sedimentation rate (ESR) less than 20 mm/h and radiographs of the lumbar spine without evidence of compression fracture or lytic or blastic lesion. 8 The ESR is a laboratory test that measures the distance that erythrocytes have fallen after 1 hour in a vertical column of anticoagulated blood; it is a nonspecific screening test used to detect occult processes and monitor inflammatory conditions. 6 Recently, Joines et al 17 conducted a decision analysis to assess the effectiveness of 11 different plausible diagnostic strategies in diagnosing spinal malignancy in primary care patients with LBP. The diagnostic strategies differed in their use of clinical findings, ESR, and radiographs of the lumbar spine, prior to utilizing advanced diagnostic imaging methods (bone scan and magnetic resonance imaging) and percutaneous vertebral biopsy. Based upon their analysis of cost effectiveness and sensitivity and specificity, Joines et al 17 recommended advanced diagnostic imaging for patients with a history of cancer or 1 or more clinical findings (failure to improve with conservative medical treatment during the past month, age of at least 50 years or older, and unexplained weight loss) in combination with either an elevated ESR ( 50 mm/hr) or positive radiographic findings (sensitivity, 0.67; specificity, 0.99; positive likelihood ratio, 67; negative likelihood ratio, 0.33) (Figure 1). 17 We believe physical therapists should have an understanding of the clinical findings associated with the presence of cancer causing LBP, as this information provides important guidance as to when laboratory testing and radiographs should be ordered. The results of these tests will then assist in determining whether a patient s symptoms are related to mechanical dysfunction or serious underlying disease. The purpose of this resident s case problem is to provide a description of a patient initially seen in a direct access physical therapy setting, with LBP and left lower extremity pain and tingling, who was subsequently diagnosed with small cell carcinoma of the lung with metastases to the spine and pelvis. The authors will include a description of how the physical therapist used both clinical examination findings and a lack of improvement with conservative measures to initiate further medical evaluation, which resulted in a diagnosis of cancer as the primary cause of the patient s low back and hip pain. DIAGNOSIS History A 45-year-old man (height, cm; mass, 72.7 kg), with chief complaints of intermittent variable History of cancer,* age 50 y, weight loss, or failure to improve with conservative treatment ESR 50 mm/h _ Conventional _ radiographs + Stop Advanced diagnostic imaging and/or biopsy FIGURE 1. A recommended testing strategy for detecting underlying cancer in patients with low back pain, adapted from Joines et al. 17 Advanced diagnostic imaging is recommended for patients with a history of cancer or 1 or more clinical findings (failure to improve with conservative medical treatment during the past month, age greater than or equal to 50 years, and unexplained weight loss), in combination with either an elevated erythrocyte sedimentation rate ( 50 mm/h) or positive radiographic findings. ESR, erythrocyte sedimentation rate. *Patients with a history of cancer may proceed directly to advanced diagnostic imaging without assessing erythrocyte sedimentation rate or conventional radiographs J Orthop Sports Phys Ther Volume 35 Number 10 October 2005

3 tingling in his left leg had started within the week prior to his initial physical therapy visit. He reported a history of intermittent left-sided LBP that was not functionally limiting and no symptoms had ever extended into his thigh in the past. The patient reported no history of cancer, hypertension, diabetes, or recent weight changes, and no other concerns pertaining to general health. He reported bowel and bladder function to be normal. He had never taken steroid or anticoagulant medications, and no diagnostic imaging had been performed for this current condition. The patient was not a smoker. The only medication he was taking was over the counter Ibuprofen. Physical Examination Journal of Orthopaedic & Sports Physical Therapy FIGURE 2. Location and description of patient s symptoms at the time of the initial physical therapy visit. left-sided LBP that extended into his left posterior thigh and intermittent variable tingling along the anterolateral aspect of his left lower extremity (Figure 2), was seen by a physical therapist without physician referral in the internal medicine department of a large regional medical center. This was the patient s first visit to this facility and he had never been seen by any other health care professional for his current condition; therefore, medical records were not available for the physical therapist. The patient worked as a quality control manager for a pharmaceutical lab. His job required sitting for approximately 50% of the day and occasional lifting of boxes weighing between 4.5 and 9.1 kg. Activities or positions that increased or aggravated all of the patient s symptoms included lying supine, coughing and sneezing, prolonged walking, and sitting for longer than an hour. Activities that decreased or eased the patient s symptoms included applying a heating pad to his low back region and taking over-the-counter Ibuprofen (200 mg) every 4 hours. The patient noted his symptoms were most intense in the evening and into the night, with pain sometimes causing him difficulty with falling asleep. The patient also remarked that he would sometimes awaken because of pain, but he was able to fall asleep rather quickly after finding a comfortable position. His symptoms were least intense in the morning. The patient reported that his left-sided LBP and posterior thigh pain had been present for a couple of months with no known incident that precipitated the onset of symptoms. The patient noted that the The patient s gait was mildly antalgic when weight bearing on the left lower extremity. Visual observation of active trunk range of motion in standing revealed a moderate decrease in extension that resulted in left-sided LBP. Trunk side bending to the left was slightly decreased and resulted in left-sided LBP and posterior thigh pain. Range of motion for trunk flexion and right side bending did not change the patient s symptoms and were judged to be within functional limits. A neurological screen revealed reduced strength of the left hip flexors and knee extensors, with Achilles and patellar deep tendon reflexes being normal bilaterally. Based on visual observation, hip passive range of motion testing into flexion, internal rotation, or external rotation was equal bilaterally and did not alter the patient s symptoms. However, with the hip flexed to 90, adduction of the left hip was limited to 0, compared with 20 of adduction on the right. During left hip adduction with the hip flexed to 90, the patient s left posterior thigh pain was reproduced. Based on visual observation, crossed passive straight leg raise testing of the right lower extremity was limited to 60 due to perceived tightness in the right hamstring musculature; no increase in the patient s symptoms was noted. Ipsilateral passive straight leg raise testing of the left lower extremity was limited to 45, due to increased left posterior thigh pain. Interpretation of the History and Physical Examination The history and physical examination can provide important information regarding whether a patient s signs and symptoms are associated with a condition that is mechanical in nature for which physical therapy intervention is indicated. In our opinion, several components of this patient s history and physical examination were consistent with a mechanical neuromusculoskeletal dysfunction. For example, this patient s chief complaint was intermittent, variable, left-sided LBP extending into his left posterior RESIDENT S CASE PROBLEM J Orthop Sports Phys Ther Volume 35 Number 10 October

4 thigh, which was consistent with a referred pain pattern that may be caused by structures in the lumbar spine. 12,21,22,23 Additionally, the intermittent variable tingling along the anterolateral aspect of the patient s left lower extremity was consistent with sensory disturbances (ie, paresthesias), which often accompany a nerve root that has been injured or damaged. 14 The patient s pain intensity also worsened with prolonged walking and sitting, as well as with trunk extension, trunk side bending to the left, and passive straight leg raise testing of the left lower extremity during the initial physical examination, suggesting that specific postures and movements altered the mechanical load on the patient s spine and left hip, and subsequently changed his symptoms. 4 While several components of this patient s history and physical examination were consistent with a mechanical neuromusculoskeletal dysfunction, there were signs and symptoms present that may have been suggestive of more serious underlying disease. 25,28 First, the patient reported that his most intense pain was in the evening and into the night, which sometimes caused difficulty with falling asleep. The patient also reported that he would sometimes awaken because of pain, but he was able to fall asleep rather quickly after finding a comfortable position. According to Deyo and Diehl, 8 the most sensitive finding from the patient history for cancer causing LBP is not having relief with bed rest (sensitivity, 0.95), suggesting that a negative response to this finding (ie, pain is relieved with bed rest) significantly reduces the odds that cancer is causing the patient s LBP (negative likelihood ratio, 0.11) (Table 1). A positive response to this finding (ie, pain is not relieved with bed rest) is not as helpful because it is rather nonspecific for cancer as a cause of LBP (specificity, 0.46), 8 as it is not uncommon for patients with activity-related LBP, presumably not caused by cancer, to have pain severe enough to wake them from sleep. 4 Boissonnault and Di Fabio 4 reported that while 52 of 98 subjects referred to physical therapy for the treatment of activity-related LBP experienced pain severe enough to wake them from sleep (ie, night pain), only 1 of these patients reported that their most intense pain was during the night, as the patient in this resident s case problem did. Second, there was concern over what we considered to be a rather atypical restricted motion pattern at the left hip (ie, passive left hip adduction being limited, while passive hip flexion, internal rotation, and external rotation were equal bilaterally) and the patient s left posterior thigh pain being reproduced with passive hip adduction. The pattern of hip motion restriction seen in this patient may be consistent with a noncapsular pattern, as the capsular pattern of the hip has been characterized by limited flexion, abduction, and internal rotation, slight limitation of extension, and little to no limitation of external rotation. 5 Because a noncapsular pattern of restricted hip motion may be indicative of serious underlying pathology, it has been recommended that further testing (ie, radiographs or magnetic resonance imaging) is indicated for patients with a noncapsular pattern of restriction and a strong reproduction of symptoms with passive hip range of motion testing. 15 Based upon the patient s somewhat suspicious historical findings (ie, most intense pain being in the evening and into the night, with pain sometimes causing difficulty falling asleep), as well as the atypical and perhaps noncapsular pattern of restricted hip range of motion, the physical therapist recommended that the patient schedule an appointment with his physician for medical evaluation of his current condition. However, because there were signs and symptoms associated with a mechanical neuromusculoskeletal dysfunction (ie, quality and location of symptoms, specific postures, and movements altering the patient s symptoms), a short-term course of physical therapy treatment was undertaken. Physical therapy visit frequency was scheduled for once a week, based on what the patient could easily attend and the physical therapist s clinical experience having patients with similar clinical presentations. Because the patient did not demonstrate any of the strong predictive findings for cancer as a cause of LBP, such as a prior history of cancer, age of at least 50 years or greater, or unexplained weight loss, 8 failure to improve with conservative treatment over the course of a month would be an important finding that would prompt further medical testing (laboratory testing and diagnostic imaging studies). When evaluating cancer as a cause of LBP, failure to improve with a month of conservative treatment has a positive likelihood ratio of 3 (Table 1); 8 this suggests that a positive response to this finding (ie, lack of improvement with a month of conservative treatment) would indicate the need for further medical evaluation. Course of Intervention and Outcomes According to Maitland et al, 20 rotation is one of the most useful procedures to use when treating conditions related to the lumbar spine. They note that rotational procedures are most valuable for symptoms that are unilateral in distribution, whether they are localized to the lumbar region or referred to the lower extremity. 20 Therefore, during the initial visit, with the patient lying on his right side, a general lumbar rotational oscillatory technique was used for approximately 5 minutes to treat the left hip and low back region. 20 Following this intervention, the symptoms and range of motion limitations seen with trunk extension and side bending to the left were not changed. Additionally, left hip adduction with the hip flexed to 90 was still limited to 0, and there was no change in the patient s left posterior thigh pain with 654 J Orthop Sports Phys Ther Volume 35 Number 10 October 2005

5 TABLE 2. Relative dates of the patient s medical visits or procedures. Date Day 1 Day 8 Day 16 Day 21 Day 24 Day 29 Day 34 Day 42 Day 44 Day 55 Medical Visits or Procedures Initial physical therapy visit Second physical therapy visit Third physical therapy visit Physical therapist informed the physician about the patient s symptom profile and lack of progress with physical therapy intervention Radiographs of the lumbar spine completed Initial physician visit Fourth physical therapy visit Fifth and final physical therapy visit Laboratory testing and radiographs of the pelvis and left hip completed Bone scan completed Radiographs and computed tomography scanning of the chest completed Thoracentesis and bone biopsy performed Oncologist visit when diagnosis and therapeutic options for small cell carcinoma of the lung with multiple areas of bony metastases were discussed with patient the motion of hip adduction. However, we questioned whether a single 5-minute bout of a general lumbar rotational oscillatory technique was enough to cause a meaningful change in the patient s main impairments. Therefore, in an effort to continue to examine the usefulness of a rotational treatment procedure, the patient was instructed in a lower trunk rotation exercise in supine hooklying that was to be performed every 2 to 3 hours. He was also educated in appropriate sitting and sleeping postures. The patient s second physical therapy visit was 7 days after his initial evaluation. The patient reported slight temporary pain reduction after performing the lower trunk rotation exercise, but no overall improvement in his condition. Physical exam findings had not changed from the initial visit, in that decreased trunk extension and side bending, as well as limited left hip adduction, were still noted. Pertinent additional physical examination findings were hypomobility with central posteroanterior pressures over the spinous process of L5 (as compared to other lumbar levels), a slight decrease in passive left hip extension based on visual observation (approximately 10 of passive left hip extension compared to 15 of passive right hip extension), a negative prone knee bend test bilaterally, and reduced strength of the left hip abductors, which was assessed with the patient lying on his right side. Both central posteroanterior pressures over the spinous process of L5 and passive left hip extension reproduced the patient s left-sided LBP that extended into his left posterior thigh and tingling along the anterolateral aspect of his left lower extremity. For the patient s 4 physical therapy visits after the initial evaluation, treatment consisted of manual intervention and stretching exercises to address hypomobility of the lumbar spine and left hip. In addition to the lower trunk rotation exercise in supine hooklying, the patient s home exercise program included left hip stretching exercises. Despite these interventions, the patient s condition gradually worsened. Specifically, the patient s symptoms became more constant, sitting tolerance was decreased, and the patient s gait became more antalgic to the point of requiring the use of a single-point cane for walking activities. Additionally, impairments noted on physical examination did not improve, despite manual intervention and a home exercise program. Overall, the patient had 5 physical therapy visits over the course of 29 days. As previously noted, the physical therapist requested that the patient schedule an appointment to see his primary care physician after the initial physical therapy visit, primarily because of concerns over the patient s most intense symptoms being in the evening and into the night, difficulty falling asleep because of the pain, and the atypical pattern of restricted hip range of motion. The patient s appointment to see his physician was not until 20 days after his initial physical therapy visit (Table 2 provides relative dates of the patient s medical visits and procedures), primarily because there were no prior appointments that the patient could easily attend. After the patient s third physical therapy visit, but prior to his physician visit, the physical therapist informed the physician about the patient s symptom profile and lack of progress with physical therapy intervention. Radiographs of the lumbar spine were then ordered by the physical therapist, who then reviewed the radiographs with the radiologist. The radiologist s report noted mottled lucencies overlying the left sacroiliac wing, that were thought to represent stool within the colon (Figure 3). Two weeks after radiographs of the lumbar spine were completed, the patient s physician ordered laboratory testing (complete blood count, metabolic panel, and ESR) and radiographs of the pelvis and left hip, primarily because mottled lucencies can be an indicator of serious pathology and the physician was informed by the physical therapist that there was a lack of improvement in the patient s signs and symptoms relating to the low back and left hip with conservative measures. 8,29 Laboratory testing revealed an elevated ESR (33 mm/h [normal, 0-15 mm/h]) and alkaline phosphatase (370 U/L [normal, U/L]). Alkaline phosphatase is an enzyme found primarily in the liver, gall bladder, intestines, and bone tissues. Highly RESIDENT S CASE PROBLEM J Orthop Sports Phys Ther Volume 35 Number 10 October

6 FIGURE 3. Anterior-posterior radiograph of the lumbar spine demonstrating mottled lucencies overlying the left sacroiliac wing (oriented to the right in this image). FIGURE 4. Anterior-posterior radiograph of the pelvis and left hip demonstrating distinct abnormalities with the bony texture of the left iliac bone and upper portion of the left sacral ala (oriented to the right in this image). This radiograph was completed 2 weeks after radiographs of the lumbar spine (Figure 3) were completed. elevated alkaline phosphatase usually indicates involvement of the liver or bony tissue. 6 For the radiographs of the pelvis and left hip, the radiologist s report noted distinct abnormalities with the bony texture of the left iliac bone, signified by a fluffy confluence and increased bone density. Similar findings also appeared to be present over the superimposed upper portion of the left sacral ala (Figure 4). A bone scan was then performed that revealed increased abnormal uptake compatible with metastatic disease throughout the spine, sacrum, and left hemipelvis (Figure 5). Further evaluation included radiographs and computed tomography scanning of the chest, which demonstrated innumerable small nodules in the lung fields bilaterally, with a larger mass in the upper left lobe. After further medical evaluation, the patient was diagnosed with small cell carcinoma of the lung, with multiple areas of bony metastases. Despite 2 cycles of chemotherapy, the patient succumbed to the cancer 5 months after he was first seen in physical therapy. DISCUSSION The patient reported in our case was first seen for his condition by a physical therapist without physician referral. While several components of this patient s history and physical examination were consistent with a mechanical neuromusculoskeletal dysfunction, there were signs and symptoms present that may have been suggestive of more serious underlying disease, including the patient s most intense pain being in the evening and into the night, difficulty falling asleep because of the pain, and the atypical pattern of restricted hip range of motion. 4,15,25,28 Based upon these findings from the initial physical therapy visit, the physical therapist recommended that the patient schedule an appointment with his physician for medical evaluation of his current condition. One of the clinical findings that later prompted radiographic and laboratory evaluation of this patient was a lack of improvement with conservative measures in the patient s signs and symptoms relating to the low back and left hip. 8 For the patient in this case, it was relatively easy to determine that his condition was worsening, because his symptoms became more constant, his sitting tolerance decreased, and his gait became antalgic to the point of requiring the use of a single-point cane for walking activities. For other patients with similar symptoms, however, it may be more difficult to assess whether a patient s condition is either worsening or improving. Therefore, we recommend that physical therapists use patient selfreport measures, such as the Oswestry Disability Questionnaire 10 or ordinal numeric pain scale ratings, at the initial physical therapy visit and then periodically through the course of physical therapy to assess patient progress. 24 While there are many variations of the straight leg raise test, it is often used to assess lumbar nerve roots and their response to tension. 1,9,18 Several reports have evaluated the accuracy of straight leg raise testing for the diagnosis of herniated lumbar discs. 1,7,19,26 In a recent review of the literature, Lurie 19 reported that, when attempting to determine 656 J Orthop Sports Phys Ther Volume 35 Number 10 October 2005

7 the presence of herniated lumbar discs, the ipsilateral straight leg raise test has been shown to be sensitive (range, ; pooled estimate, 0.91), but not specific (range, ; pooled estimate, 0.26), and the crossed straight leg raise test has been shown to be specific (range, ; pooled estimate, 0.88), but not sensitive (range, ; pooled estimate, 0.29). 19 Based on the pooled estimates of sensitivity and specificity, Lurie 19 calculated a positive likelihood ratio of 1.2 and a negative likelihood ratio of 0.3 for the ipsilateral straight leg raise test, and a positive likelihood ratio of 2.4 and a negative likelihood ratio of 0.8 for the crossed straight leg raise test. Although the patient in this resident s case problem had a positive ipsilateral straight leg raise test and a negative crossed straight leg raise test, we concluded that the straight leg raise test results did little to change the odds regarding the presence of a herniated lumbar disc, based upon the data presented by Lurie. 19 Although LBP due to metastatic cancer suggests that an underlying neoplasm is already advanced, it is thought that there is therapeutic value in prompt diagnosis, because specific treatment can be initiated. 8 Therefore, it is important that physical therapists utilize sound history taking and physical examination principles at both initial evaluation and follow-up visits, and closely monitor response to treatment. 2,3 Although many of the history and physical examination findings commonly discovered by physical therapists are not necessarily indicative of specific pathologies, these findings may indicate the need for communication with the patient s physician. In this case, for example, that the most intense pain was in the evening and into the night, the difficulty falling asleep because of the pain, the atypical pattern of restricted hip range of motion, and lack of progress with physical therapy prompted the physical therapist to comprehensively discuss this patient s case with his physician, which led to radiographic and laboratory evaluation for more serious underlying disease. In patients with known malignancy, radiographic evidence of bony destruction or sclerosis may be indicative of a metastatic lesion. 29 However, bony destruction of 30% to 50% is necessary for a lytic lesion to appear on radiographs, suggesting that some metastatic lesions may be present but not detected on radiographs. 29 Therefore, physical therapists should use caution in assuming that metastatic cancer is not present in patients with LBP simply because their radiographs do not demonstrate evidence of a lytic or blastic lesion. In a study of 1975 consecutive patients seeking medical care for LBP in a walk-in primary care clinic in a public hospital, Deyo and Diehl 8 reported that 13 patients had LBP related to underlying cancer. It is interesting to note that no patient who had cancer had both an ESR of less than 20 mm/h and radiographs of the lumbar spine without evidence of compression fracture or lytic or blastic lesion, 8 suggesting that there is some diagnostic value in ruling out cancer when an ESR less than 20 mm/h and normal radiographic findings are combined. While the peak incidence of lung cancer is in smokers around the age of 60 years, 3,13,16 it is interesting to note that our patient was not a smoker. However, his father was a heavy smoker, suggesting an exposure to second-hand smoke while our patient was growing up. Additionally, the patient had a 10-year history of working with hazardous chemicals in an environmental laboratory, which may have been a contributing factor to his condition. While there are several different types of lung cancers, the patient in this case was diagnosed with small cell carcinoma of the lung, which has a very rapid growth rate, with metastases to the axial skeleton typically occurring very early in the course of the disease. 13 The pain associated with the bone lesion can be the initial presenting symptom of lung cancer even before lung lesions are detected on radiographs or symptoms associated with pulmonary dysfunction develop (ie, cough, dyspnea, wheezing, malaise, bloody sputum, weight loss). 3 In the case of our patient, radiographs of the chest were not performed until 6 weeks after his initial physical therapy visit (Table 2), which demonstrated innumerable small nodules in the lung fields bilaterally, with a larger mass in the upper left FIGURE 5. Bone scan revealing increased abnormal uptake compatible with metastatic disease throughout the spine, sacrum, and left hemipelvis. An anterior view is on the left and a posterior view is on the right. RESIDENT S CASE PROBLEM J Orthop Sports Phys Ther Volume 35 Number 10 October

8 lobe. According to the patient s medical record, it was also about this time that he began to develop a cough and dyspnea and experience weight loss. Because metastases to the spine are common from lung cancer, as well as other types of cancers, such as those relating to the prostate, thyroid, breast, and kidney, 3,11,13,29 it is important that physical therapists be familiar with the specific signs and symptoms of dysfunction for these organs so that appropriate medical referral can be made as necessary. CONCLUSION It is important that physical therapists have an understanding of the clinical findings associated with the presence of serious underlying diseases causing LBP. In the patient described in this resident s case problem, for example, an understanding of the clinical findings associated with the presence of cancer causing LBP provided guidance as to when communication with the patient s physician was warranted, as well as when laboratory testing and radiographs should have been ordered. ACKNOWLEDGEMENT The authors thank Michael Bang, PT, OCS for his thoughtful insight and assistance with this paper. REFERENCES 1. Andersson GB, Deyo RA. History and physical examination in patients with herniated lumbar discs. Spine. 1996;21:10S-18S. 2. Boissonnault WG, Bass C. Pathological origins of trunk and neck pain: Part I - Pelvic and abdominal visceral disorders. J Orthop Sports Phys Ther. 1990;12: Boissonnault WG, Bass C. Pathological origins of trunk and neck pain: Part III - Diseases of the musculoskeletal system. J Orthop Sports Phys Ther. 1990;12: Boissonnault WG, Fabio RP. Pain profile of patients with low back pain referred to physical therapy. J Orthop Sports Phys Ther. 1996;24: Cyriax J. Textbook of Orthopedic Medicine. 8th ed. London, UK: Balliere Tindall; Daniels R. Delmar s Guide to Laboratory and Diagnostic Tests. Albany, NY: Delmar Thompson Learning, Inc; Deville WL, van der Windt DA, Dzaferagic A, Bezemer PD, Bouter LM. The test of Lasegue: systematic review of the accuracy in diagnosing herniated discs. Spine. 2000;25: Deyo RA, Diehl AK. Cancer as a cause of back pain: frequency, clinical presentation, and diagnostic strategies. J Gen Intern Med. 1988;3: Deyo RA, Rainville J, Kent DL. What can the history and physical examination tell us about low back pain? JAMA. 1992;268: Fairbank JC, Couper J, Davies JB, O Brien JP. The Oswestry low back pain disability questionnaire. Physiotherapy. 1980;66: Fornasier VL, Horne JG. Metastases to the vertebral column. Cancer. 1975;36: Fukui S, Ohseto K, Shiotani M, Ohno K, Karasawa H, Naganuma Y. Distribution of referred pain from the lumbar zygapophyseal joints and dorsal rami. Clin J Pain. 1997;13: Goodman CC. The respiratory system. In: Goodman CC, Boissonnault W, eds. Pathology: Implications for the Physical Therapist. Philadelphia, PA: W.B. Saunders Co; 1998: Greensberg D, Aminoff M, Simon RP. Clinical Neurology. 5th ed. New York, NY: McGraw Hill; Greenwood MJ, Erhard RE, Jones DL. Differential diagnosis of the hip vs. lumbar spine: five case reports. J Orthop Sports Phys Ther. 1998;27: Hinson JA, Jr., Perry MC. Small cell lung cancer. CA Cancer J Clin. 1993;43: Joines JD, McNutt RA, Carey TS, Deyo RA, Rouhani R. Finding cancer in primary care outpatients with low back pain: a comparison of diagnostic strategies. J Gen Intern Med. 2001;16: Jonsson B, Stromqvist B. The straight leg raising test and the severity of symptoms in lumbar disc herniation. A preoperative evaluation. Spine. 1995;20: Lurie JD. What diagnostic tests are useful for low back pain? Best Pract Res Clin Rheumatol. 2005;19: Maitland GD, Hengeveld E, Banks K, English K. Maitland s Vertebral Manipulation. London, UK: Butterworth-Heinemann; McCulloch JA, Waddell G. Variation of the lumbosacral myotomes with bony segmental anomalies. J Bone Joint Surg Br. 1980;62-B: Mooney V, Robertson J. The facet syndrome. Clin Orthop Relat Res. 1976; Ohnmeiss DD, Vanharanta H, Ekholm J. Relation between pain location and disc pathology: a study of pain drawings and CT/discography. Clin J Pain. 1999;15: Resnik L, Dobrzykowski E. Guide to outcomes measurement for patients with low back pain syndromes. J Orthop Sports Phys Ther. 2003;33: ; discussion Roach KE, Brown M, Ricker E, Altenburger P, Tompkins J. The use of patient symptoms to screen for serious back problems. J Orthop Sports Phys Ther. 1995;21: van den Hoogen HM, Koes BW, van Eijk JT, Bouter LM. On the accuracy of history, physical examination, and erythrocyte sedimentation rate in diagnosing low back pain in general practice. A criteria-based review of the literature. Spine.1995;20: Waddell G. The Back Pain Revolution. New York, NY: Churchill Livingstone; Weinstein JN, McLain RF. Primary tumors of the spine. Spine. 1987;12: Wong DA, Fornasier VL, MacNab I. Spinal metastases: the obvious, the occult, and the impostors. Spine. 1990;15: J Orthop Sports Phys Ther Volume 35 Number 10 October 2005