1 - LBP Red Flags Flashcards
In multiple myeloma, what advanced imaging is usually normal?
Bone Scans
In multiple myeloma, what advanced imaging is usually positive?
MRI
In what patient profile should you suspect multiple myeloma?
50+ years olds with chronic low back pain and anemia of chronic disease (possible history of recurrent infections)
What blood test has very high sensitivity for multiple myeloma (if negative, unlikely to be multiple myeloma)?
Serum protein electrophoresis
What test is done to confirm multiple myeloma after serum protein electrophoresis and MRI have been done?
Bone marrow aspiration
What is the first step in differential diagnosis of NMS conditions?
Determine if due to injury or disease, must rule out disease first
About what percentage of LBP is due to serious disease?
3%
About what percentage of low back pain is due to cancer or spinal infection?
1%
About what percentage of low back pain is due to referred pain from viscera?
2%
Referred pain from viscera that causes low back pain is usually from what 3 systems?
GI
Reproductive
Urinary
What percentage of a diagnosis is made by patient history?
90%
How do you calculate a positive likelihood ratio from sensitivity and specificity numbers?
Sensitivity / (1- specificity)
How do you calculate a negative likelihood ratio from sensitivity and specificity numbers?
(1 - sensitivity)/ specificity
In 2000 consecutive patients with back pain, no patient < 50 was found to have cancer unless they had at least one of these findings:
Prior history of cancer
Unexplained weight loss
Failure of 1 month of conservative treatment
What are the biggest red flags from the history that would indicate multiple myeloma?
Weight loss (rule in)
Failure of bed rest to relieve pain (rule out)
Age is 50+
Is night pain correlated with serious disease?
Sometimes but not often enough to be included in guidelines
Excruciating back pain when lying supine, relieved by sitting up, hunched over a table is common with what serious disease
Malignant retroperitoneal lymphadenopathy
Malignant retroperitoneal lymphadenopathy is usually secondary to what two types of primary cancers?
lymphomas (more common in elderly) and testicular cancer (more common in young men)
When leg symptoms are present (with or without
accompanying LBP), the index of suspicion for an organic
pathology increases, especially patients who are
- female
- pediatric
- geriatric
What are 3 important physical exam findings that would point towards bone cancer?
- neurological deficits in older patient
- exquisite pain with spinal percussion
- significant restriction at multiple segments in multiple directions
What is the clinical strategy when you have a patient with persistent back pain and/or neurological deficit?
X-ray first
Do spinal percussion
What are the first three ancillary studies in your clinical strategy if you suspect disease?
- Plain films
- ESR and/or CRP
- CBC
In addition to your first three ancillary studies that you perform when disease is suspected, what additional tests could be ordered if cancer or infection is suspected?
Blood chemistry panel (Calcium, ALP, proteins)
In addition to your first three ancillary studies that you perform when disease is suspected, what additional tests could be ordered if arthritic condition is suspected?
- anti CCP, RF, ANA, HLA-B27
In addition to your first three ancillary studies that you perform when disease is suspected, what additional tests could be ordered if GU problem is suspected?
Urinalysis
If you suspect disease and plain films are normal but you still have high suspicion, what ancillary tests would you order next?
MRI, CT, bone scan or SPECT
What percentage of bone cancers are metastatic? Primary?
2/3 are metastatic
1/3 are primary
Metastatic bone cancer usually comes from what 4 primary cancers?
- breast
- lung
- prostate
- kidney
Sometimes from colon or thyroid
Are most metastatic bone cancers osteolytic or osteoblastic?
Osteolytic
What primary cancer, when it metastasizes to the bone is osteoblastic?
Prostate
What are the first blood tests to run in a neuromuscular case when trying to rule out disease?
ESR and/or CRP
Then CBC
What is LeFebvre’s rule regarding ESR values?
20-50
Anything less than 20 is not clinically significant
Anything over 50 is probably a disease process (get more testing)
Between 20-50 would have to be a judgement call based on other clinical indicators
What are the three diseases that commonly present with an ESR over 100
Multiple myeloma
Temporal arteritis
Polymyalgia rheumatic a
What combination of ancillary test results are a very sensitive screen for serious malignancies or infections in NMS conditions?
Normal ESR and X-ray is very sensitive (good at ruling out serious disease)
What combination of 4 signs and symptoms from the history had 100% sensitivity for cancer in LBP patients?
- prior history of cancer
- unexplained weight loss
- failure to improve in 1 month
- over 50 years old
Increased WBC count (as seen with increased ESR) in a patient with chronic low back pain can indicated what diseases?
- infection
- cancer
- inflammatory disease
Increased immature WBC in a patient with chronic LBP can indicate what disease?
Leukemia
Decreased WBC in a patient with chronic LBP can indicated what disease?
Multiple myeloma
What is being checked with a blood chemistry panel?
Proteins and other metabolic indicators
What are the two most common causes of elevated serum calcium?
- metastatic cancer (osteolytic)
- hyperparathyroid (unlikely to cause back pain)
- these two account for about 90% of hypercalcemia
- osteoporosis does not cause increased serum calcium
When would you see elevated ALP (alkaline phosphatase)?
- metabolically active bone (growing and healing fracture, Paget’s disease, pregnancy, liver disease)
- osteoblastic bone cancer
What percentage of patient with metastatic bone cancer will have elevated calcium?
40-50%
What percentage of patients with metastatic bone cancer will have elevated alkaline phosphatase?
50-75%
What organ systems most commonly have viscerosomatic referral pain to the low back?
- reproductive
- urinary
- gastrointestinal
Back pain from viscera will often have one or more of these characteristics?
- coincide with menstrual cycle
- be periodic and unassociated with movement or activity
- colicky or cramping
- writhing pain
Low Back pain plus what three things would cause suspicion (red flag) that pain is not musculoskeletal?
- little or no muscle spasm
- little or no tenderness on palpation
- little or no impairment of segmental mobility
Bilateral thoracolumbar referred pain, usually associated with nausea or vomiting, made worse with recumbency is commonly associated with what organ?
Pancreas
Relief of low back pain by what pathognomic position is a strong indicator for pancreas as cause of low back pain?
Knees drawn up and forward flexed
What is the pain referral pattern for the urinary bladder?
Central spot on superior gluteal cleft and posteromedial upper thigh
What is the pain referral pattern for kidney
Flanks and lateral hip/thigh
Usually unilateral
Pain may be present on opposite side because visceral nerves cross midline
Where does the colon (except sigmoid) refer pain to?
Mid lumbar spine
Where do gynecological disorders refer pain to?
Low back, rarely above L4
Where does the sigmoid colon and rectum refer pain to?
Sacral area
What are some examples of gynecological conditions that could cause referred back pain?
- endometriosis
- Fallopian tube
- ruptured ovarian cyst
- ectopic pregnancy
When will spinal percussion be positive?
Fracture, spinal infection, cancer
