Knee Exam

Aka: Knee Exam, Knee Examination, Knee Joint Finding, Knee Maneuver

1. See Also
   1. Knee Injury Acute History
   2. Knee Pain
2. Exam: Telemedicine
   1. See Telemedicine
   2. Both knees should be exposed (e.g. shorts)
   3. Evaluate patients gait from front and side (see standing exam below)
   4. Perform knee general exam as below (observation, self-palpated tenderness and range of motion)
   5. Perform specific knee tests as able (see below)
   6. Consider Knee XRay or other imaging indications
      1. Ottawa Knee Rule (if Knee Pain after Trauma)
      2. Inability to actively extend the knee (e.g. Patella injury, quadriceps Tendon Injury)
3. Exam: General (compare with less affected knee)
   1. Observation
      1. Erythema
      2. Deformity
      3. Swelling or joint effusion
      4. Ecchymosis
      5. Overlying skin changes
      6. Knee Effusion or swelling with obscured landmarks
         1. See Knee Effusion Causes
         2. See Ballottable Patella Sign
         3. See Knee Bulge Sign
      7. Previous surgical scars
      8. Knee resting position
      9. Quadriceps muscle atrophy
         1. Evaluate Vastus Medialis Obliquus specifically
         2. Atrophy often on side of Ligamentous Injury
   2. Tenderness to Palpation
      1. Patella
      2. Tibial tubercle
      3. Patellar tendon
      4. Quadriceps tendon
      5. Joint line
      6. Pes Anserine Bursa
      7. Iliotibial Band
   3. Normal Knee Range of Motion
      1. Flexion: 135 degrees
      2. Extension: 0 to -10 degrees (above horizontal plane)
4. Exam: Patellofemoral
   1. Quadriceps Femoris Muscle Angle (Q Angle)
   2. Patella tracking with quadriceps contraction
      1. Evaluate for smoothness of motion and crepitation
   3. Patellar Apprehension Test
      1. Evaluates for Patella Subluxation
5. Exam: Anterior Cruciate Ligament (ACL) Stability Tests
   1. Lachman Test (most sensitive)
   2. Knee Anterior Drawer Test
   3. Pivot Shift Test (MacIntosh Test)
6. Exam: Posterior Cruciate Ligament (PCL) Tests
   1. Knee Posterior Drawer Test
   2. PCL Sulcus Test
   3. PCL Sag Test
7. Exam: Collateral ligament evaluation
   1. Knee Valgus Stress Test (Medial collateral ligament)
   2. Knee Varus Stress Test (Lateral collateral ligament)
8. Exam: Meniscus Evaluation
   1. McMurray's Test
   2. Apley's Compression Test and Apley's Distraction Test
   3. Knee Bounce Test
   4. Thessaly Test
   5. Inability to fully extend knee may suggest "bucket-handle" meniscal tear
   6. Joint line tenderness is 76% sensitive for meniscal tear, but not specific
9. Exam: Neurovascular
   1. Leg Motor Exam
   2. Distal sensation
   3. Deep Tendon Reflexes (Patella, achilles)
   4. Distal pulses (dorsalis pedis, posterior tibial)
10. Exam: Standing evaluation
    1. Balanced weight on each leg
    2. Deformity
       1. Genu Varum
          1. 
       2. Genu Valgum
          1. 
    3. Gait analysis
    4. Patella baja or Patella alta deformity
    5. Hip, Knee, and ankle alignment
11. Imaging
    1. See Knee XRay Indications in Acute Injury (e.g. Ottawa Knee Rule)
    2. Knee Ultrasound Indications
       1. Dynamic tendon evaluation (e.g. Patellar tendon, quadriceps tendon)
       2. Collateral ligament evaluation
       3. Baker Cyst
       4. Neurovascular evaluation
       5. Knee Effusion evaluation (esp. to direct needle aspiration)
    3. Knee MRI Indications
       1. Occult Fracture not visualized on XRay (CT may also be used)
       2. Malignancy
       3. Vascular Injury
       4. Osteomyelitis
       5. Potential surgery (ACL or PCL Tear, vertical meniscal tear)
       6. Mechanical symptoms refractory to trial of physical therapy
12. Diagnostics: Knee Arthrocentesis
    1. See Monoarthritis or Polyarthritis
    2. Indications
       1. Large, painful Knee Effusion of unclear etiology
    3. Simple clear transudative fluid
       1. Knee sprain
       2. Chronic meniscal tear
    4. Hemarthrosis (Bloody effusion)
       1. Anterior Cruciate Ligament Tear
       2. Osteochondral Fracture (Tibial Plateau Fracture)
       3. Acute meniscal tear
    5. Pustular Drainage
       1. Septic Joint
13. References
    1. Bach (1997) Physician Sportsmed, 25(5): 39-50
    2. Budoff (1997, April) Consultant, 919-30
    3. Budoff (1997, Feb) Consultant, 295-304
    4. Hoppenfeld (1976) Physical Exam, Prentice-Hall
    5. Bunt (2018) Am Fam Physician 98(9): 576-85 [PubMed]
    6. Calmbach (2003) Am Fam Physician 68(5):907-12 [PubMed]
    7. Rothenberg (1993) Postgrad Med, 93(3): 75-86 [PubMed]
    8. Smith (1995) Am Fam Physician 51(3):615-21 [PubMed]
    9. Solomon (2001) JAMA 286:1610-20 [PubMed]
    10. Yedlinsky (2021) Am Fam Physician 103(3):147-54 [PubMed]