Musculoskeletal System

Common Diagnostic Tests

ANA, antinuclear antibodiesDetects SLE, a collagen disease

Arthritis can result from SLE

Normal = negative

Client prep

CRP, C-reactive proteininflammation and auto-immune disorders show abnormal protein

Normal = female 1-20, male 1-13mm/h Can get false negative

Client Prep, usually non-fasting blood draw

Uric Acid-BloodElevated with Gout and arthritis

Normal = male 2.1-8.5, female 2.0-6.6 mg/dl

Client prep: usually non-fasting blood draw

Uric Acid-Urine (24 hour collection)

Normal = 250-750 ml/24hr

Client prep

CBC

HemoglobinIncrease can mean CHF

Decrease can mean SLE or sarcoidosis

Normal = male 14-18, female 12-16 g/dl

Client prep

CBC

WBCelevated with infection/inflammation

Normal + 5,000 – 10,000/mm3

Client prep

ESR, Erythrocyte Sedimentation RateRBC descent in saline in 1 hour

Increases with inflammation, infection, necrosis, or cancer

Normal = male up to 15, female up to 20 mm/hr

Client prep

RF, Rheumatoid Factor (IgM)Elevated with autoimmune disease such as Rheumatoid arthritis and SLE

Normal = < 60 U/ml or negative

Client prep

Serum Calcium, detects calcium metabolismIncrease may indicate: metastatic bone tumor, Paget’s disease, acromegaly

Decrease may indicate: rickets, osteomalacia, vitamin D deficiency

Normal = 9.0 – 10.5 mg/dl< 6mg/dl may lead to tetany (cramps, convulsions, twitching)

> 14mg/dl may lead to coma

Client prep

Radiologic StudiesArthrogram/Arthrography-Xray with contrast dye into joint to visualize soft tissue of joints (meniscus, ligaments, cartilage)

Arthrogram

Client prep

Arthrogram Procedure:Cleanse & anesthetize area

Insert needle into joint space

Aspirate fluid to minimize dilution of dye

Leave needle in, replace syringe with dye syringe

Inject contrast and remove needle

ROM to distribute dye

X-rays will be taken

Takes about 30 minutes

May experience some discomfort, pressure, tingling

Following Arthrogram:Assess for swelling

Apply ice, if needed

Mild analgesic

May hear crepitus after test. This is normal and will disappear in 1-2 days.

Instruct pt to call MD if pain or swelling occurs

CT ScanX-ray (body scanner) with contrast dye

Three-dimensional cross-sectional view of tissues at various angles

Can identify small differences: Detects edema, hemorrhage, blood flow, infarcts, tumors, infections, aneurysms, demyelinating disease, muscular disease, skeletal abnormalities, disk problems, causes of spinal cord compression

Takes about an hour

Findings as with arthrogram, but 3-D view

CT Scan

Client prep

Following CT Scan

Increase fluid intake to flush dye

Evaluate patient for delayed reaction to dye (usually occurs within 2-6 hours)

Treat with antihistamine and/or steroids, if indicated

CT Scan Procedure

Patient must lie still

Show picture of CT machine and discuss claustrophobia, may need antianxiety med

Performed by a radiologist

Takes 30-45 minutes

Discomfort includes lying still on a hard surface, peripheral venipuncture, mild nausea, salty taste, flushing, and warmth from dye

MRI

MRI/Magnetic Resonance ImagingMagnetic field and radio waves, noninvasive

Can evaluate soft & hard tissue, & blood vessels

Unique d/t no exposure to ionizing radiation

Advantages over CT

Disadvantages

MRI

Contraindications:> 300 lbs

Claustrophobia

Metal implants, clips, pacemaker, infusion pumps

Pregnancy (long-term effects not known)

If on continuous life support

Client prep:Obtain consentCan drive afterwards without assistanceAssess for contraindicationsShow picture of machine, discuss claustrophobiaRemove all metal objects from body (create artifacts, can go flying, damages credit cards)Must remain motionless in supine positionWill hear thumping sound, ear plugs availableEmpty bladder prior to test for comfortNo food or fluid restrictions prior to testExplain procedure

MRI Procedure

Lie flat on hard table that slide into a tubeMust lie stillCan talk to or listen to staffMagnevist (contrast agent) may be used via IVPerformed by radiologistTakes 30 to 90 minutesDiscomfort from lying on hard surface, possible venipuncture, possible tingling in teeth (metal fillings)No postprocedural care needed

MRI

Detects: edema, hemorrhage, blood flow, infarcts, tumors, infections, aneurysms, demyelinating disease, muscular disease, skeletal abnormalities, disk problems, causes of spinal cord compression

X-ray

X-ray, electromagnetic radiation passes photons (light particles) through the body onto film

Bone (very dense) blocks photons, appears white

Air appears black

Muscle, fat, and fluid appear as various shades of gray

Metal and contrast block almost all photons and appear bright white

X-ray

Client prepNonfastingPosition determined by area to be x-rayedPatient should be still, usually hold breathContraindicated if pregnantMay need to remove jewelry & don a gownNo discomfort except r/t position

Detects fractures and some joint abnormalities

Myelogram

MyelogramX-ray with contrast dye of spinal subarachnoid spaceDetects spinal tumors, herniated discs, bone spurs, cervical ankylosing spondylosis, arthritic lumbar stenosisContraindications: Multiple sclerosis patients (may cause exacerbation), ICP, infection near lumbar puncture sight, allergy to shellfish

Myelogram

Client prep

Myelogram ProcedureEmpty bladderA lumbar puncture is performed

15 ml CSF removed15 ml of radiopaque dye injected

Patient will be tilted up and down to spread dye (prone position)Lights are off, dye followed with fluoroscopyX-ray films takenNeedle remains in place until exam concludedDone by radiologist and takes 45 minutesDiscomfort varies from mild to severe

Following Myelogram

Bed rest for several hours

Head position varies per dye used, per MD order

Monitor for bleeding, fever, headache, photophobia, seizure, VS, ability to void, reaction to dye

Possible med restrictions

Push fluids

Bone ScanBone Scan

Radioactive isotope intravenous

They use a gamma camera to detect “hot spots” of activity where the isotope collects

Can detect tumor, arthritis, fracture, necrosis, degenerative changes, osteomyelitis

Normal = uniform distribution

Abnormal = area of higher concentration

Contraindicated in pregnancy, breastfeeding

Bone Scan

Advantages:

Disadvantages:

Bone Scan

Client prep:Explain procedure, is non-fasting, no sedation required

Arrive at Nuclear Medicine department 4 hours prior to test

Dye given IV, takes 4 hours to travel to bones

Push fluid to aid in dye distribution

Empty bladder upon return to avoid artifact

You may be asked to wear a gown

Done in supine, prone, & lateral position, takes an hour

Takes 6-24 hours for dye to leave system (push fluids)

Discomfort is needle stick for dye infusion, and hard surface

Bone Mineral Density/BMD

BMDMeasures bone mass

The only test to diagnose osteoporosis

Normal is comparative to same age, sex, size. Lower density = higher risk for fractures

-1 to –2, Osteopenia

< -2.5, Osteoporosis

Client prep: Non-fasting, non-invasive, do Q2 yrs

Other Tests

ArthrocentesisObtain synovial fluid from a joint

Needle aspiration

Sterile procedure

Detects infections, synovitis, crystal-induced arthritis, tumors, joint degeneration

Inject anti-inflammatory medications

Normal= Clear, straw-colored fluid, no crystals

Contraindicated if infection near joint being tested

Arthrocentesis cont’dInformed consent

Explain procedure

May or may not be fasting

Local anesthetic

Aseptic procedure

Fluid may be removed, Steroid may be injected

Apply pressure dressing following procedure

May do venipuncture to compare chemical content

Doctor office or bedside, by MD, takes 10 minutes

Pain may worsen after test

Following Arthrocentesis Assess for pain, fever, swelling

Apply ice

Apply pressure dressing to decrease reaccumulation of fluid or hematoma

Avoid strenuous use of joint for several days

Arthroscopy-used most often for kneeSmall incision, endoscope

Examine the inside of a joint

Diagnose disease, meniscus problems, torn cartilage, remove small bodies, do biopsy

Advantage: allows direct visualization, can perform surgery, can monitor disease progress, can attach video camera; can examine, biopsy, or do surgery

Contraindications:Infection or ankylosis in joint

ArthroscopyClient prep:

Obtain consent

NPO at midnight

Teach crutch use for post procedure use

Shave 6” above and below joint

May use local or general anesthesia

Pressure wrap or tourniquet

Knee at 45 degree angle

May have 2-3 small incision sights

Sutured with dressing applied

Done by orthopedic surgeon, takes 15 to 30 minutes

Arthroscopy Follow-upAsses neurologic status and circulatory status

Assess for sxs of infection, for drainage

Teach to elevate & ice to decrease swelling

May walk with crutches if MD order

Suture removal in 7-10 days