Special Operations Forces Medical Handbook

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not count.

b. Pelvic compression: with the patient supine on a rm surface press downward and inward on

the anterior superior iliac crests. This stresses the SI joints. In a patient with sacroiliitis this

should cause pain localized to the SI joint.

3. Assess ROM:
   a. Limited lumbar mobility as measured by the Schober maneuver: place a mark on the back
   in the midline at the level of the presacral dimples, approximately L5. Measure upward and
   make another mark 10 cm toward the head on the midline of the spine. Have the patient
   bend forward and touch his toes. The best measurement should be after the third try,
   with repeated bending providing maximum soft tissue stretch. The distance between the
   marks should be 5 cm greater in a bent position compared to straight position.
   b. A normal Schober maneuver with the measurement increasing from 10 – 15 cm goes against
   the diagnosis of ankylosing spondylitis. A measurement of 0 mm would be seen in a
   totally fused spine. A measurement of 1 - 3 cm suggests ankylosing spondylitis. Some
   limitation at 4 cm may be seen in either ankylosing spondylitis or a process with severe
   pain and muscle spasm.

Using Advanced Tools: Laboratory plays a limited role and X-ray changes may be delayed for months
to years.
If there is signicant joint effusion in a single accessible joint, it should be aspirated (see Procedure: Joint
Aspiration). Joint aspiration is not essential in a polyarthritis. Septic joints are almost always monoarticular.
Lab:

1. Synovial uid cell count with hemacytometer:
   a. WBC < 2000 with < 75% PMNs = noninamatory uid - Osteoarthritis, Trauma, Viral infection
   b. WBC > 2000, but <50,000 (5000 - 15,000 common) with 75 - 90% PMNs = inamatory uid -
   gout, pseudogout, viral, Lyme disease, rheumatoid arthritis, other arthritis
   c. WBC > 50,000 = septic joint until proven otherwise
   d. RBC: TNTC RBC = hemarthrosis - major trauma including fracture, internal derangement (ACL,
   meniscal tear), bleeding disorder


2. Gram Stain: Positive if infected with staph or strep; may be negative if infected by gonococcus 50% of the
   time


3. WBC: Elevated WBC with a left shift favors infection but does not rule out gout or inammatory process.
   Low WBC with lymphocytosis suggests viral illness.


4. Urinalysis: Proteinuria, hematuria, and RBC casts are seen in glomerulonephritis, which is associated with
   many types of polyarthritis including lupus, and some infections like endocarditis, Hepatitis B&C,
   osteomyelitis, HIV


5. Monospot in the appropriate clinical setting can conrm the diagnosis of mononucleosis.


6. RPR in the appropriate clinical setting can conrm the diagnosis of syphilis.

• remember false positive VDRL (+ RPR with NEG FTA-abs) can be seen in lupus-like connective tissue
  diseases

Assessment:
Differential Diagnosis: Pain in one or more joints is a common presenting symptom of decompression
sickness (see Dive Medicine Chapter).
Acute Monoarthritis:
Tendonitis, bursitis and other soft tissue inammation usually involves one joint region and can be
distinguished from true arthritis by physical exam.
Mono- or oligoarthritis (very few joints) implies trauma, infection or crystal induced arthritis. History of
trauma suggests fracture or hemarthrosis.
Joint-centered tenderness, redness, and swelling most common in gout or septic joint.
a. A family history of gout or kidney stones and history of similar previous episodes suggests
gout. Abrupt onset with maximum pain in 12-24 hrs is likely gout or other crystal induced process.
b. Chills, sweats, and fever more common with septic joint but does not rule out gout. Gradual
onset over several days suggests infection, with or without fever.