Skip to content
  • About
  • Contact
  • Contribute
  • Book
  • Careers
  • Podcast
  • Recommended
  • Speaking
  • All
  • Physician
  • Practice
  • Policy
  • Finance
  • Conditions
  • .edu
  • Patient
  • Meds
  • Tech
  • Social
  • Video
    • All
    • Physician
    • Practice
    • Policy
    • Finance
    • Conditions
    • .edu
    • Patient
    • Meds
    • Tech
    • Social
    • Video
    • About
    • Contact
    • Contribute
    • Book
    • Careers
    • Podcast
    • Recommended
    • Speaking

MKSAP: 20-year-old man with a 6-month history of low back pain

mksap
Conditions
February 16, 2013
Share
Tweet
Share

Test your medicine knowledge with the MKSAP challenge, in partnership with the American College of Physicians.

A 20-year-old man is evaluated for a 6-month history of low back pain accompanied by prolonged morning stiffness. His symptoms improve over the course of the day, but he is now unable to play recreational soccer. Rest, physical therapy, and acupuncture have not improved his symptoms. Use of ibuprofen or diclofenac provides only partial relief. He has no other pertinent medical history and takes no additional medications.

On physical examination, vital signs are normal. There is loss of normal lumbar lordosis, and flexion of the lumbar spine is decreased. The low back and pelvis are tender to palpation. Pain increases when the patient crosses his legs. Reflexes and muscle strength are intact.

Radiographs of the lumbar spine and sacroiliac joints are normal.

Which of the following studies is most likely to establish the diagnosis in this patient?

A: Bone scan
B: CT of the sacroiliac joints
C: MRI of the lumbar spine
D: MRI of the sacroiliac joints

MKSAP Answer and Critique

The correct answer is D: MRI of the sacroiliac joints. This item is available to MKSAP 16 subscribers as item 41 in the Rheumatology section.

MKSAP 16 released Part A on July 31. More information is available online.

This patient most likely has ankylosing spondylitis, and MRI of the sacroiliac joints is most likely to establish a diagnosis. Radiographic evidence of sacroiliitis is required for definitive diagnosis and is the most consistent finding associated with this condition. Onset of ankylosing spondylitis usually occurs in the teenage years or 20s and manifests as persistent pain and morning stiffness involving the low back that is alleviated with activity. This condition also may be associated with tenderness of the pelvis.

Typically, the earliest radiographic changes in affected patients involve the sacroiliac joints, but these changes may not be visible during the first few years from onset; therefore, this patient’s normal radiographs of the sacroiliac joints do not exclude sacroiliitis. MRI findings of the sacroiliac joints can include bone marrow edema, synovitis, and erosions. Bone marrow edema is the earliest finding and can precede the development of erosions. MRI, especially with gadolinium enhancement, is considered a sensitive method for detecting early erosive inflammatory changes in the sacroiliac joints and spine and can assess sites of active disease and response to effective therapy.

Bone scan can demonstrate increased uptake of the sacroiliac joints in patients with ankylosing spondylitis but is less sensitive and specific than MRI.

CT is the most sensitive modality available to demonstrate bone changes such as erosions; however, it cannot detect early changes such as bone marrow edema that precede erosive change in patients with ankylosing spondylitis.

In the diagnosis of early ankylosing spondylitis, sacroiliac joint MRI is more sensitive than lumbar spine MRI. Although changes to the lumbar spine can be detected on MRI, they are usually preceded by changes in the sacroiliac joints. Therefore, if imaging of the lumbar spine is negative, subsequent imaging of the sacroiliac joints would still be necessary to exclude ankylosing spondylitis.

ADVERTISEMENT

Key Point

  • MRI is considered the most sensitive method for detecting early erosive inflammatory changes in the sacroiliac joints when radiographs are normal.

Learn more about ACP’s MKSAP 16.

This content is excerpted from MKSAP 15 with permission from the American College of Physicians (ACP). Use is restricted in the same manner as that defined in the MKSAP 15 Digital license agreement. This material should never be used as a substitute for clinical judgment and does not represent an official position of ACP. All content is licensed to KevinMD.com on an “AS IS” basis without any warranty of any nature. The publisher, ACP, shall not be liable for any damage or loss of any kind arising out of or resulting from use of content, regardless of whether such liability is based in tort, contract or otherwise.

Prev

The EMR template: I want to believe

February 15, 2013 Kevin 19
…
Next

Part of medical education is to learn limitations

February 16, 2013 Kevin 0
…

Tagged as: Orthopedics

Post navigation

< Previous Post
The EMR template: I want to believe
Next Post >
Part of medical education is to learn limitations

ADVERTISEMENT

More by mksap

  • a desk with keyboard and ipad with the kevinmd logo

    MKSAP: 26-year-old man with back pain

    mksap
  • a desk with keyboard and ipad with the kevinmd logo

    MKSAP: 36-year-old man with abdominal cramping, diarrhea, malaise, and nausea

    mksap
  • a desk with keyboard and ipad with the kevinmd logo

    MKSAP: 52-year-old woman with osteoarthritis of the right hip

    mksap

More in Conditions

  • How President Biden’s cognitive health shapes political and legal trust

    Muhamad Aly Rifai, MD
  • The emotional first responders of aesthetic medicine

    Sarah White, APRN
  • Why testosterone matters more than you think in women’s health

    Andrea Caamano, MD
  • How veteran health care is being transformed by tech and teamwork

    Deborah Lafer Scher
  • What Elon Musk and Diddy reveal about the price of power

    Osmund Agbo, MD
  • Understanding depression beyond biology: the power of therapy and meaning

    Maire Daugharty, MD
  • Most Popular

  • Past Week

    • The hidden health risks in the One Big Beautiful Bill Act

      Trevor Lyford, MPH | Policy
    • How New Mexico became a malpractice lawsuit hotspot

      Patrick Hudson, MD | Physician
    • Why doctors are reclaiming control from burnout culture

      Maureen Gibbons, MD | Physician
    • Why health care leaders fail at execution—and how to fix it

      Dave Cummings, RN | Policy
    • How digital tools are reshaping the doctor-patient relationship

      Vineet Vishwanath | Tech
    • How President Biden’s cognitive health shapes political and legal trust

      Muhamad Aly Rifai, MD | Conditions
  • Past 6 Months

    • Why are medical students turning away from primary care? [PODCAST]

      The Podcast by KevinMD | Podcast
    • What the world must learn from the life and death of Hind Rajab

      Saba Qaiser, RN | Conditions
    • Why “do no harm” might be harming modern medicine

      Sabooh S. Mubbashar, MD | Physician
    • Here’s what providers really need in a modern EHR

      Laura Kohlhagen, MD, MBA | Tech
    • The hidden health risks in the One Big Beautiful Bill Act

      Trevor Lyford, MPH | Policy
    • Why Medicaid cuts should alarm every doctor

      Ilan Shapiro, MD | Policy
  • Recent Posts

    • How President Biden’s cognitive health shapes political and legal trust

      Muhamad Aly Rifai, MD | Conditions
    • Decoding your medical bill: What those charges really mean

      Cheryl Spang | Finance
    • The emotional first responders of aesthetic medicine

      Sarah White, APRN | Conditions
    • Why testosterone matters more than you think in women’s health

      Andrea Caamano, MD | Conditions
    • A mind to guide the machine: Why physicians must help shape artificial intelligence in medicine

      Shanice Spence-Miller, MD | Tech
    • How subjective likability practices undermine Canada’s health workforce recruitment and retention

      Olumuyiwa Bamgbade, MD | Physician

Subscribe to KevinMD and never miss a story!

Get free updates delivered free to your inbox.


Find jobs at
Careers by KevinMD.com

Search thousands of physician, PA, NP, and CRNA jobs now.

Learn more

Leave a Comment

Founded in 2004 by Kevin Pho, MD, KevinMD.com is the web’s leading platform where physicians, advanced practitioners, nurses, medical students, and patients share their insight and tell their stories.

Social

  • Like on Facebook
  • Follow on Twitter
  • Connect on Linkedin
  • Subscribe on Youtube
  • Instagram

ADVERTISEMENT

  • Most Popular

  • Past Week

    • The hidden health risks in the One Big Beautiful Bill Act

      Trevor Lyford, MPH | Policy
    • How New Mexico became a malpractice lawsuit hotspot

      Patrick Hudson, MD | Physician
    • Why doctors are reclaiming control from burnout culture

      Maureen Gibbons, MD | Physician
    • Why health care leaders fail at execution—and how to fix it

      Dave Cummings, RN | Policy
    • How digital tools are reshaping the doctor-patient relationship

      Vineet Vishwanath | Tech
    • How President Biden’s cognitive health shapes political and legal trust

      Muhamad Aly Rifai, MD | Conditions
  • Past 6 Months

    • Why are medical students turning away from primary care? [PODCAST]

      The Podcast by KevinMD | Podcast
    • What the world must learn from the life and death of Hind Rajab

      Saba Qaiser, RN | Conditions
    • Why “do no harm” might be harming modern medicine

      Sabooh S. Mubbashar, MD | Physician
    • Here’s what providers really need in a modern EHR

      Laura Kohlhagen, MD, MBA | Tech
    • The hidden health risks in the One Big Beautiful Bill Act

      Trevor Lyford, MPH | Policy
    • Why Medicaid cuts should alarm every doctor

      Ilan Shapiro, MD | Policy
  • Recent Posts

    • How President Biden’s cognitive health shapes political and legal trust

      Muhamad Aly Rifai, MD | Conditions
    • Decoding your medical bill: What those charges really mean

      Cheryl Spang | Finance
    • The emotional first responders of aesthetic medicine

      Sarah White, APRN | Conditions
    • Why testosterone matters more than you think in women’s health

      Andrea Caamano, MD | Conditions
    • A mind to guide the machine: Why physicians must help shape artificial intelligence in medicine

      Shanice Spence-Miller, MD | Tech
    • How subjective likability practices undermine Canada’s health workforce recruitment and retention

      Olumuyiwa Bamgbade, MD | Physician

MedPage Today Professional

An Everyday Health Property Medpage Today
  • Terms of Use | Disclaimer
  • Privacy Policy
  • DMCA Policy
All Content © KevinMD, LLC
Site by Outthink Group

Leave a Comment

Comments are moderated before they are published. Please read the comment policy.

Loading Comments...