LLD Exam

Four Physical Outcomes

 

1.  Symmetrical Stance & Level Pelvis 

 

A.  LL Equality

- Components equal with no deformity

 

B.  Components equal with bilateral symmetrical deformity

- eg Bilateral varus knees

 

2.  Symmetrical Stance with Oblique Pelvis 

 

Uncompensated LLD

 

3.  Asymmetrical Stance & Level Pelvis 

 

A. Fully Compensated LLD

- Flexed contralateral knee 

- Equinus ipsilateral ankle

 

B. Sagittal deformity with ipsilateral sagittal compensation

- FFD knee with Equinus & hip flex OR

- Fixed Equinus with flex knee & hip OR

- FFD hip with equinus & flex knee

 

C.  Coronal deformity with contralateral coronal deformity

- Valgus of knee & contralat varus of knee

 

4. Asymmetrical Stance with Oblique Pelvis 

 

A.  Partly compensated LLD

- Partly flexed contralateral knee

- Partly equinus of ipsilateral ankle

 

B. Coronal hip deformity with sagittal compensation

- Fixed hip adduction with contralateral knee flexion / ipsilateral equinus

- Fixed hip abduction with ipsilateral knee flexion / contralat equinus

 

C.  Sagittal def c coronal compensation

- FFD knee c ipsilateral hip abduction

- Fixed equinus c ipsilateral hip ADD

 

Leg length Examination

 

1.  Look

 

Posture

- flexed knee

 

Signs hemihypertrophy

- NF
- haemangiomas / lipomas (Proteus, Klippel-Trenau-Weber, Beckwith)

 

Scars

- trauma, infection

 

Aids / Shoes

- heel inserts / raises

 

2.  Gait

 

Children

 

Compensate well 

- Walk on toes short leg usually / equinus

- Flexion long knee uncommon as energy++

 

Adults

 

Compensate less well

- Walk with bilateral heel-toe gait

- Vaults over long leg

- Excess Sagittal head motion

 

3.  Measure LLD
 

A.  Functional LLD

- on blocks

- heels flat, nil knee FFD (if able)

- correct pelvic tilt

- should correct scoliosis

 

Conclusion

- if can make pelvis stable

- ASIS equal

- blocks are a quantitative measure of functional LLD

 

B.  Apparent LLD

 

Lying on bed

- measure from xiphisternum to medial malleolus

- no correction for contractures

 

C. Real / True LLD

 

Must correct for deformity in coronal and sagittal plane

 

Exclude

- hip adduction / abduction contracture

- hip FFD

- knee FFD

 

Scenarios

1.  Hip FFD

- pillow under both thighs

2.  Knee FFD

- pillow under both knees

3.  Hip adduction contracture won't correct to neutral

- measure each leg crossed over the other

4.  Hip abduction contracture won't correct to neutral

- place both legs in similar position

 

If there is a contracture, perform the above measures

- then meaure the intercalated segments

- from ASIS to medial joint line

- medial joint line to medial malleolus

 

4.  Identify site of shortening

 

Galeazzi

- must not forget can have small foot / old calcaneal fracture / wasted buttock

- hips and knees flexed

- side by side

- look for tibial / femoral shortening

 

If shortening above knee, find out if shortened above greater trochanter

- i.e. hip deformity

 

Bryant's triangle

- line perpendicular to GT and ASIS

- distance between

- quantify in fingerbreadths

 

Nelaton's line

- line from ischial tuberosity to ASIS

- GT should be on or below line

 

Klisics line

- GT to ASIS

- should aim to umbilicus

- will be more parallel

 

5.  Other

 

Examine Knee stability

- can have problems lengthening femur if ACL deficient

- i.e. fibula hemimelia