Notes on Medical Imaging of the Lower Spine

Introduction to Lower Quarter Medical Imaging

• Overview of medical imaging in lower quarter assessment

• Importance of medical imaging for physical therapists
  

Role of Physical Therapists in Medical Imaging

• Not the primary orderers of medical imaging, but crucial in discussing and interpreting results

• Responsibilities include:
    - Counseling patients on appropriate imaging options
    - Understanding costs, risks, and benefits of imaging

• Need to differentiate imaging techniques based on:
    - Diagnosis
    - Body regions
    - Tissue types
  

Guidelines for Medical Imaging in Physical Therapy

• Entry-level clinicians must understand:
    - Indications for medical imaging in practice
    - Evaluation process for patients
    - Clinical practice guidelines that dictate medical imaging utility

• Focus on lumbar spine imaging
  

Indications for Imaging the Lumbar Spine

• Adults under 50 with no systemic symptoms:
    - Conservative care and therapy without imaging is advised

• Adults over 50 or with suspected systemic disease:
    - Plain film radiographs / X-rays and lab tests recommended

• MRI or advanced imaging reserved for:
    - Surgical considerations
    - Strong suspicion of systemic disease
  

Specific Imaging Recommendations

Lumbar Film Orders

• Routine evaluation of acute low back pain within the first month:
    - Plain films not recommended without red flags
    - Exceptions:
      - Recent significant trauma
      - Patients over 50 with mild trauma
      - Patients over 70 with acute onset of low back pain
      - History of prolonged steroid use or osteoporosis

• Chronic conditions extending beyond 4-6 weeks of conservative care may require imaging
  

Imaging Techniques and Protocols

• Preferred views for plain film radiographs:
    - Anterior-posterior, lateral views
    - Avoid oblique views due to increased radiation exposure
    - Exceptionally used for spondylolisthesis or spinal instability suspicion

• Considerations for bone scans for:
    - Suspected tumors, infections, occult fractures
  

Advanced Imaging Considerations

• MRI and CT myelograms:
    - Not recommended in the first month of treatment unless red flags are present
    - MRI has approximately 95% accuracy in correlation with neurological deficits
    - MRI preferred over CT due to lower radiation exposure

• EMG testing can identify neural compression via electrical activity assessment
   

Efficacy and Cost of Imaging

Study Comparisons

• Studies show:
    - MRI does not significantly improve health outcomes compared to X-rays but increases costs
    - Patients with MRIs are more likely to undergo surgery despite no change in outcomes

• Cost-effectiveness analysis:
    - x-rays are preferable if no red flags, while usual care without imaging is sufficient
    - High patient satisfaction with x-ray imaging despite negligible benefit in clinical outcomes
  

Clinical Guidelines

• Recommendations from the American College of Physicians and the American Pain Society:
    - Imaging considered for patients with progressive neurological deficits
    - Routine imaging not beneficial and may lead to unnecessary surgery
    - Over-utilization of imaging resources highlighted as an inefficiency
  

Lumbar Imaging in Clinical Practice

Degenerative Conditions

• Patients showing degenerative changes on imaging do not necessarily require MRI

• Evidence against routine MRI for chronic low back pain based on:
    - Lack of link between degenerative findings and improvement in low back pain from surgical interventions
    - No substantiation for procedural treatments based on MRI findings
  

Imaging Recommendations for Spinal Pathologies

Infection and Neoplasms

• Indicators for MRI:
    - Localized pain, fever, lab abnormalities suggesting infection

• Differentiation between infection and neoplasm from imaging findings
  

Neoplasms

• Common metastatic diseases to the spine include:
    - Lung, renal, breast cancer, multiple myeloma

• Bone scans recommended for initial staging and monitoring treatment efficacy
  

Osteoporosis Imaging Strategies

DEXA Scans

• Gold standard for osteoporosis diagnosis; plain films insufficient till 30% bone loss

• Typical scanning sites:
    - Lumbar spine
    - Neck of femur

• Result interpretation:
    - Normal (within 1 SD), Osteopenia (1-2.5 SD), Osteoporosis (>2.5 SD)

• Criteria for ordering:
    - Prior fractures, metabolic disorders, chronic diseases that contribute to bone loss