Case 11 - 74 yo with knee pain

Question 1

Differential diagnosis for knee pain in 74 yo w/o trauma

Answer 1

Osteoarthritis, RA, SLE, Gout, psoriatic arthritis, knee strain

Question 2

Leading cause of disability?

Answer 2

Osteoarthritis

Question 3

Prevalence?

Answer 3

22% of adult americans have MD-diagnosed arthritis

Question 4

DDx for knee pain in kids

Answer 4

patellar subluxation, osgood schlatter (tibial apophysitis), patellar tendonitis

Question 5

DDx for knee pain in adults

Answer 5

Patellofemoral pain syndrome, overuse (bursitis), ACL, MCL, LCL or meniscal tears, RA, septic arthritis etc

Question 6

What diagnoses are more likely with monoarticular joint involvement?

Answer 6

Gout (often the toe!), OA (knees, hip, back), RA - usually three or more joints and often small ones (fingers, feet)

Question 7

Knee exam outline

Answer 7

Observe (standing, walking, climbing on table)
Inspect (erythema, edema, bruising, quad atrophY)
Palpate (warmth, effusion, point tenderness, joint line)
Evaluate (ROM, crepitus, effusions)

Question 8

Lachman’s test

Answer 8

Tests ACL, move femur posterior and move tibia anterior

Question 9

Anterior and posterior drawer

Answer 9

Tests ACL and PCL

Question 10

Valgus and varus stress tests

Answer 10

Tests MCL and LCL respectively

Question 11

McMurray Test

Answer 11

tests mensicus, check for clunk

Question 12

Carpal tunnel exam

Answer 12

Look for asymmetry, atrophy of thenar eminence, strength of hand and wrist, tap over median nerve

Question 13

Phalen’s test

Answer 13

Flex wrist by putting backs of hands together for 30-60 seconds to reproduce sx, positive test indicates carpal tunnel

Question 14

Most salient features of carpal tunnel exam

Answer 14

Pt has sx in digits 1,2,3 only, and some palm; patient has decreased sensitivity to pain, weak thumb abduction with strength testing

Question 15

Joint aspiration findings

Answer 15

Septic arthritis: opaque fluid, abundant WBC (150-200k), no crystals
Gout: turbid fluid, moderate WBC (3-15k), crystals present

Question 16

Ankylosing spondylitis

Answer 16

form of chronic inflammatory process with back pain, and hips (less so knees)

Question 17

SLE

Answer 17

migratory arthritis usually associated with rash, fever, raynaud’s etc

Question 18

Patellofemoral syndrome

Answer 18

Anterior knee pain, usually overuse, mild-moderate pain after prolonged sitting

Question 19

Iliotibial band tendonitis

Answer 19

lateral knee pain, overuse, pain aggravated with activity

Question 20

ACL

Answer 20

general knee pain, assoc with trauma, effusion and swelling common

Question 21

MCL

Answer 21

medial joint line pain, assoc with (valgus stress) trauma, immediate pain/swelling

Question 22

LCL

Answer 22

lateral joint line pain, assoc with varus stress, immediate pain

Question 23

Meniscal tear

Answer 23

Medial or lateral joint line pain, assoc with twisting injury, can also be chronic degenerative, mild effusion

Question 24

Septic arthritis

Answer 24

Generalized extreme pain, no trauma, fever and elevated WBC

Question 25

OA

Answer 25

generalized or joint line pain, pain aggravated by activity, relieved by rest, no acute trauma, chronic join stiffness and pain, crepitus on exam

Question 26

Gout

Answer 26

extreme pain with movement, no fever, no trauma, acute pain and swelling, positive for crystals

Question 27

Simple joint effusion

Answer 27

clear, straw-colored transudative fluid - seen in OA or degenerative meniscal injury

Question 28

Hemarthrosis

Answer 28

dark, bloody, seen in acute meniscal tear or ACL/PCL injuries

Question 29

Hemarthrosis with fat globules

Answer 29

dark, bloody with fat, seen in osteochrondral fracture

Question 30

Infected

Answer 30

turbid fluid with high wbc, seen in septic arthritis

Question 31

Inflammation

Answer 31

turbid fluid with moderate wbc, seen in ra, SLE, and gout

Question 32

Xrays in OA

Answer 32

not required to diagnose OA but can help with diff dx, see osteophytes, joint space narrowing, subchondral sclerosis, subchondral cysts

Question 33

MRI for knees?

Answer 33

For meniscal or ligamentous damage

Question 34

Management of Osteoarthritis

Answer 34

Rx: exercise to reduce pain/disability, glucosamine, chondroitin, NSAIDs, acetaminophen, intra-articular corticosteroids, tramadol (B level evidence)

Acetominophen is first line for rx bc highly tolerable and low side effects (some nephro and hepatotox)
NSAIDs are next line, not preferred because of risk of gastric ulcers and bleeding and affect on other meds
COX-2 have less risk of GI but greater risk of CV events
Tramadol - less potential for abuse than opioids, approp for moderate to severe pain
Steroid injections - if joint is inflamed, no more than 3/year, use triamcinolone

Question 35

Chronic pain management

Answer 35

Setting realistic goals
Tramadol - less risk of abuse than opioids
Short acting opioid - helpful for acute pain, but high risk of tolerance and abuse
Long acting opioids - used for chronic pain, constipation
TCAs - antichol side effects, contraindicated in CAD pts
Anticonvulsants - used in trigeminal neuralgia

Question 36

Carpal Tunnel Management

Answer 36

1st - nocturnal wrist splint

Consider nerve conduction study if not improving

Question 37

Preventive medicine for 74 year old woman

Answer 37

• Mammogram every 2 years (insufficient evidence to recommend at 75)
• Colonoscopy as stated by previous colonoscopy (every 3-10 years) (stops at 75)
• Cervical cancer - no need over 65
• Lipid screening if at risk for CAD
• Depression - screening in all patients
• HTN - all patients
• AAA - U/S in men 65-75 with hx of smoking
• Carotid artery stenosis - no screening in asx pts
• Immunizations (zoster after 60, tetanus every 10 yrs, pneumococcal after 65, annual flu)