Examination of the Knee

Summary

Look

Introduction
General comment
- No evidence of systemic disease
Walking aids
Shoes
- Off the shelf, commercial shoes with no modifications or insoles
- Wear pattern

Patient Standing

Feet together & pointing straight ahead, medial foot boarders parallel

Anterior Aspect

If normal say
- In the coronal plane the patient has normal anatomical limb alignment, symmetrical lower limbs with no atrophy & no evidence of surgical scars
Alignment
- Standing limb Alignment
  - Physiological valgus alignment
    - 7° in women & 5° in men
- Knees
  - genu valgum
  - genu varum
  - windswept deformity
- Patellar
  - rotation
  - squinting patellae
- Foot
  - rotation
  - symmetrical ER
Proximal to distal

skin changes

scars

well healed surgical incision

atrophic changes to the lower limb including

hair loss
venous hyperpigmentation
dry skin

varicosities
dekeratinisation

Muscles Wasting

Quads

Swellings about the knee

localized or generalized

Patella

Patellar Alignment

Gives indication of rotational malalignment in the limb

alta, baha
squinting

(point together, indicates excessive femoral anteversion, where compensatory tibial ER allows the feet to point forwards/primary tibial external torsion with hip IR)

out-facing

(habitual subluxation/dislocation, femoral retroversion)

prepatellar bursitis
patellar tendon
infrapatellar (Hoffa’s) fat pad, ganglion cysts
prominent tibial tuberosity (Osgood Schlatter)
Jumper’s knee (Sinding-Larsen-Johansson)

Turn the patient to the side

Please face the other wall sir

Please straighten your knee as much as possible

Describe position of
- Spine
- Pelvis
- Hip
- Knee
  - Fixed flexion / recurvatum
    - Causes
      - effusion
      - entrapped meniscus
      - ACL stump
      - loose body
- Ankle
- Feet

Equinus

Scars
- Tibial osteotomy

Turn the patient away from you

Please face the back wall

Spine

Sagittal deformity

Pelvis

Level

Buttock folds
Quads wasting
Popliteal creases
Calf
Hindfoot alignment
Forefoot rotation

Gait

Next get the patient to walk & note gait

Anterior & Posterior Perspectives

Thrust

Valgus varus

Antalgic
Short leg
Foot progression

Lateral Perspective

recurvatum thrust
stiff knee gait

weak quads, pain in flexion

back knee gait
flexed knee gait
shorter stride length
3 rockers

Options

Hop & turn

Tests stability

Squat
Duck-walking

Patients who can duck walk cannot have a serious meniscal injury

Patient Seated

Please sit on the side of the bed

Test Hip
Patella Height

Knee flexed at 90°
patella alta (high riding)
patella baja / infra

Patella Tracking
Patella Crepitus
Quads Lag
Quads strength
Extensor mechanism is intact

Patient Supine

Please lie down & relax

Look

Quads
- atrophy
I could quantify this with a measuring tape
- 10-15cm above patella

Feel

I’m going to press around your knee, please let me know if it hurts

Anterior Aspect

Leg in Extension

Temperature
Effusion

patella tap (ballotable patella sign)
bulge test
swipe test

patella

patella facet tenderness

medial & lateral facets

apprehension
glide
tilt

Leg in Flexion 90°

Anterior Aspect
- Inferior pole of patella
- Patella tendon
- Retropatellar fat pad
- Tibial tuberosity
Medial Aspect
- medial joint line
  - anterior portion – non specific
  - posterior portion – Osteoarthritis, meniscus tear
- medial collateral ligament
  - origin
  - insertion
- Pes Anserinus
Lateral Aspect
- lateral joint line
- LCL
  - origin
  - insertion
  - Options
    - In figure of 4
- iliotibial band & gerdy’s tubercle
- biceps tendon & fibula head
  - biceps tendinitis
Posterior Aspect
- popliteal cyst (Baker’s)

Move

Extension
- passive extension
  - recurvatum
  - flexion contracture
- Options
  - prone hanging test
    - measure heel height difference
    - 1 cm of difference = 1 degree
Flexion
- Active than passive
- Feel for crepitus
- Measure
  - heel to buttock distance
  - 130° to 150°
  - 110° enough for stairs

Special Tests

Stability Tests

valgus stress test

test in 15° flexion

relaxes PM capsule

test in full extension

+ve then damage to

sup/deep MCL
PM capsule
cruciate ligament injury

varus stress test

N: physiological varus laxity of 3-5 mm

Anterior Laxity
- Look for Posterior sag
- Lachman’s test
  - Torg JS, Conrad W, Kalen V: Am J Sports Medicine 4:84, 1976
  - Please relax your leg as much as possible
  - 15° flexion
  - normal: nil or 1-2 mm of translation with very firm endpoint
  - Tip
    - hand on the femur can also detect tight hamstrings, if tight – tell patient to relax
  - Grade
    - 0 0-3mm
    - 1 3-5
    - 2 5-10
    - 3 >10 with no endpoint
  - mention grade & end point
    - soft vs hard
- Anterior drawer test
  - neutral
    - normal: few mm movement with hard endpoint
    - hamstrings can mask ACL rupture in this test
    - some normal ACL’s can have translation in this test
    - more specific for anterior fibres
    - Assess
      - 1. degree of translation
      - 2. endpoint
    - Problems
      - 1. Hamstrings can mask translation if patient not relaxed
      - 2. ACL injuries may not be able to flex to 90°
  - 30° IR
    - PLC / lateral complex should tighten & in the normal knee reduce anterior drawer
    - abnormal laxity= injury to posterolateral corner
  - 15° ER
    - PMC / medial complex should become tight - abnormal laxity = injury to posteromedial corner
    - in
  - (the IR/ER part is called the Slocum test- Slocum etal CORR 118: 63, 1976)
- Pivot shift test
  - (Galway, Beupre, Mackintosh JBJS70A:386, 1988 "Use of the Quadriceps Active test to diagnose PCL disruption & measure posterior laxity of the knee&quot
  - helps confirm posterior subluxation when dropback is equivocal
  - Starting position
    - Patient supine, knee flexed to 90o, foot flat on the table
    - Tibia subluxed posteriorly
  - Movement
    - hold foot against table
    - ask patient to try to slide foot along the table against resistance (isometric contraction of quadriceps)
  - Result
    - Quads contraction against resistance produces anterior tibial translation
    - +ve if proximal tibia shifts anteriorly > 2mm
- dynamic posterior shift test
- Posteromedial Pivot Shift
- Starting position
  - Knee flexed > 45°
  - Tibia is subluxed posteriorly
- Movement
  - Varus stress
  - IR
  - Knee extended
- Results
  - Knee reduces ~ 20-40° short of full extension

Posterolateral laxity

Injury

Results in

tibia rotates externally an abnormal amount with respect to femur
lateral tib plateau subluxes posteriorly with respect to lateral femoral condyle

External Rotation Recurvatum Test

(Hughston & Norwood- CORR 147:82, 1980)
knees extended
grab both great toes & lift foot off table
+ve: abn knee falls into recurvatum & varus, tibia ER compared to normal knee
due to injury to PCL, LCL & posterolateral ligament complex & patients will have varus recurvatum gait

Dial Test: Tibial external rotation test (Crank / Dial Test)

Prone
knees flexed at 30°
knees flexed at 90°
foot is forcefully rotated externally
degree of rotation of the medial border of the foot is measured relative to the femur + compared with the contralateral side
NB palpate the tibial plateau to determine its relative position to the femoral condyles - this is to confirm that the ↑ ER is due to posterolateral instability rather than anteromed instability
NB considerable interindividual variation in degree of maximal ER
- at 30° flexion: average 30o, range 15-45o
- at 90° flexion: average 37o, range 15-70o
> 10° difference is positive
↑ ER at 30° & 90° → combined instability
↑ ER which is max at 30° → isolated PL corner injury

posterolateral drawer sign
- ( Hughston & Norwood- CORR 147:82, 1980)
  - due posterior drawer in ER, neutral & IR
  - +ve for posterolateral laxity if ↑ magnitude of posterior drawer in ER
reverse pivot shift test of jakob, hassler, staeubli
- ( Jakob, Acta Orthop Scand (supp) 52: 1, 1981)
- to test R knee
- examiner faces patient h
- R foot on examiner’s R pelvis
- R foot in ER
- Examiner’s L hand on lateral proximal tibia (fibula)
- Flex knee to 70°
  - This causes tibial plateau to sublux posteriorly
- Lean against foot, apply valgus force & extend knee
- At 20°, the subluxed tib plat reduces
- +ve with acute or chronic posterolateral instability
- lateral tibial plateau shifts from a position of posterior subluxation to a position of reduction as the flexed knee is extended under valgus & foot in ER
- Produces discomfort
- Simulates feeling of giving way
- Significantly positive reverse pivot suggests PCL, the arcuate complex & LCL all torn
- Disappears in position of tibial internal rotation
- May also be tested from extension to flexion
- Not specific for PLRI
- Reported as positive in 11-35% Normal subjects
- Especially with Generalized Ligament Laxity
Standing apprehension test
- Ferrari - JBJSB 1994
- patient slightly flexing knee while WB on affected leg
- ↑ IR of lateral fem condyle relative to fixed tibial plateau
- subjective experience of "Giving Way&quot
- If both then +ve
- Considered to be 100% sensitive for PLRI

Patellofemoral joint

look: size,shape,position,vmo, height
feel

osteophytes
tenderness

medial facet
lateral facet

move

quadrant glide
tilt(n=0-15)
grind,Q(N=15M20F)
tracking
creps,passive apprehension
gentle pressure on superior pole

rotational alignment

Crepitus & pain

passive patellar grind test

knee extended
press down on patella & flex knee
+ve if examiner feels distinctive crunching sensation

active patellar grind test

patient sits with knees flexed over table
press down on patella
patient actively extends knee

b) Clarkes snatch test

pressure on sup pole with contraction
cf N

step-up-step down test

patient steps up & down low stool
examiner feels for patellofemoral crepitus

Functional Instability

Apprehension Test

supine & relaxed
push patella laterally with 30 flexion
flex knee
pain & apprehension

dynamic patellar tracking

ask seated patient to extend flexed knee
watch to tracking
normally movement is straight with minimal shift & tilt laterally near terminal extension

patellar glide test (sage sign)

patient supine with knees extended & quads relaxed
patella divided into quadrants
push patella laterally & medially

to assess tightness of parapatellar structures

normal excursion is 1cm
a medial glide of 1 quadrant = tight lateral structures
lateral - N =2.5/ >3 abnormal
-med -N = 1-2.5
-<1 = tigh lateral ret
->3 = hypermobile patella

J tracking

sit on bed
patellar sharply deviates laterally in terminal extension

patellar (Fairbanks) apprehension test

supine & abduct leg
push patella laterally & slowly flex knee
+ve if patient apprehensive

Patellar Tilt test

knee extended, quads relaxed
Examiner lifts lateral edge of patella from the lateral femoral condyle
tight lateral structures indicated in neutral or negative angle to the horizontal
should rise to horizontal plane in N

Q-angle: Not routine

line from ASIS to center of patella to tibial tubercle

14° men, 17° women
– patellofemoral pain
¯– subluxation of patella

Tubercle-sulcus angle: Not routine

Knees flexed to 90°
Eliminates femoral rotation & detects abnormal lateral displacement of tibial tubercle
Line drawn from center of patellar to tib tubercle
Another line from center of patella perpendicular to a line of examination table

< 8° women, < 5° men

lateral displacement of TT
patellofemoral pain & instability

Circulation

dorsalis pedis
normal
diminished
absent
posterior tibial
popliteal
knee flexed
pulse
aneurysm

PROXIMAL JOINT

hip ROM
rotation in flexion Abd/Add in extension

POPLITEAL FOSSA

Prone
masses
flexion & extension

Examination of the Knee

Health Quality Initiative by

Western Hospital

Sunshine Hospital

Williamstown Hospital

Examination of the Knee

Summary

Look

Patient Standing

Anterior Aspect

Turn the patient to the side

Turn the patient away from you

Gait

Patient Seated

Patient Supine

Look

Feel

Anterior Aspect

Leg in Extension

Leg in Flexion 90°

Move

Special Tests

Stability Tests

Patellofemoral joint

Circulation