1. Knee Pain and the Knee Exam
February 21, 2013
Kate Lupton, MD

2. History Joint(s) involved Functional limitations
?Trauma/Injury -> Mechanism
Acute onset vs. slowly progressive
Prior problems with area
Systemic signs and symptoms

3. Principles of the MSK Exam
Good exposure (clothing removed, in gown)
LOOK
FEEL
MOVE
SPECIAL TESTS

4. LOOK

5. LOOK Alignment/Posture – Gait – heel/toe walk, squat
“Ankles together” – look at knees (genu valgus/varus)
“Ankles shoulder width apart” – look at arches (pes planus/cavus, tibial torsion)
“Turn around” – look at heel alignment, back of knees – heel valgus/varus, Baker’s cyst
Gait – heel/toe walk, squat
Knee – “SEADS” = swelling, erythema, atrophy, deformity, scars

6. LOOK

7. FEEL Find point maximal tenderness ?Reproduce sx
Effusion – patellar ballotment
Patella – check mobility, tenderness under lateral, medial, inferior facets. Apprehension – knee flexed to 20°, laterally deviate patella. If involuntary quad contraction -> positive sign
Joint line – palpate MCL, LCL, meniscal cyst
Posterior knee – muscle insertions, Baker cyst

8. FEEL

9. FEEL Patellar Ballotment Flex knee
Hand on supra-patellar pouch, push down toward patella
Push down perpendicularly on center of patella
If effusion – patella floats and “bounces” back when pushed

10. FEEL Joint line palpation slightly flex knee
Run fingers up tibia, will “drop” into joint line
Can flex/extend to confirm
Feel along medial and lateral joint lines

11. MOVE Active and passive flexion/extension
ROM – flex to °, extend 0-15°
Hyperflexion, hyperextension
Crepitus – hand over patella while flexing/extending
Resisted active flexion/extension
Neurovascular exam – motor, sensory, reflexes, cap refill, pulses
Hip/back screen – log roll leg, straight leg raise

12. MOVE

13. SPECIAL TESTS
Menisci – joint line tenderness, hyperflexion/extension, McMurray
Ligaments – Lachman, drop Lachman, anterior/posterior drawer, posterior sag, valgus/varus stress

14. SPECIAL TESTS

15. SPECIAL TESTS - Menisci
Joint line palpation
slightly flex knee
Run fingers up tibia, will “drop” into joint line
Can flex/extend to confirm
Feel along medial and lateral joint lines

16. SPECIAL TESTS - Menisci
McMurray’s – medial meniscus
Opposite hand grasps knee w/ fingers on medial JL (L hand grasps R knee)
Same hand grasps heel (R hand grasps R heel), flex knee past 90°
Turn ankle so foot and knee point outward (heel toward compartment tested)
Slowly extend knee to 90°, if positive test, feel palpable thud. Pain localizing to JL is also positive sign
Sens 29%, spec 95%

17. SPECIAL TESTS - Menisci
McMurray’s – lateral meniscus
Opposite hand grasps knee w/ fingers on medial JL (L hand grasps R knee)
Same hand grasps heel (R hand grasps R heel), flex knee
Turn ankle so foot and knee point inward (heel toward compartment tested)
Slowly extend knee to 90°, if positive feel palpable thud. Pain localizing to JL is also positive sign
Sens 29%, spec 95%

18. SPECIAL TESTS - Ligaments
Medial Collateral Ligament
Flex knee to 20-30°
One hand on inner calf/ankle
Push inward (valgus stress) on lateral knee while applying outward stress with hand on calf/ankle
Positive test = joint laxity

19. SPECIAL TESTS - Ligaments
Lateral Collateral Ligament
Flex knee to 20-30°
One hand on outer calf/ankle
Push outward (varus stress) on medial knee while applying inward stress with hand on calf/ankle
Positive test = joint laxity

20. SPECIAL TESTS - Ligaments
Lachman’s (ACL)
patient supine, knee at 20-30° flexion
Fix femur with one hand, lift tibia forward with other hand (force perpendicular to plane of tibia)
Slight external rotation of foot
Anterior force should be applied near posteromedial aspect of proximal tibia
Positive if tibia subluxes anteriorly and concavity of patellar tendon becomes convex
Sens 82%, spec 97%

21. SPECIAL TESTS - Ligaments
Drop Lachman (ACL)
Better for big legs/small hands
Patient lies with leg abducted off side of table, flexed 25°
Stabilize foot between examiner’s legs
Hold femur on table with one hand
Use opposite hand to anteriorly sublux tibia
More sensitive than Lachman as less hamstring recruitment

22. SPECIAL TESTS - Ligaments
Posterior Sag (PCL)
Patient lies supine, hip flexed to 45° and knees to 90°
Positive if absence of tibial tubercle prominence due to posterior shift of tibia

23. SPECIAL TESTS - Ligaments
Posterior Drawer (PCL)
Patient supine with knee bent to 90°
Sit on foot, grasp below knee with both hands, thumbs on anterior tibial tuberosity
Push backward – if intact PCL, feel distinct endpoint
If PCL disrupted, tibia feels unrestrained in posterior translocation

24. SPECIAL TESTS – patellofemoral pain and chondromalacia
Slightly flex knee
Push down on patella with both thumbs – pain if chondromalacia
Hold patella in place with hand, direct patient to contract quadriceps, forcing inferior surface of patella onto femur – elicits pain if chondromalacia

25. Many thanks to:
Anthony Luke, MD – UCSF Charlie Goldberg, MD – UCSD