Femur Flashcards
(35 cards)
What is the angle of femoral inclination, and what is the norm in a newborn child and in an adult?
- angle formed between the long axis of the HoF and NoF and the long axis of the shaft of the femur
- newborn: 150 degrees
- adult: 128 degrees
What is coxa valga?
- increased angle of inclination
- femoral inclination angle has not reduced to 128 degrees
What is coxa vara?
- decreased angle of inclination
- femoral inclination angle has reduced past 128 degrees
What are some signs of coxa valga?
- degree of HJ dislocation
- may be associated with genu varum
What may cause coxa valga?
- lack of development of the HoF and NoF relative to the shaft (dysplasia)
- trauma may cause unilateral coxa valga
What are some signs of coxa vara?
- shorter limb on affected side
- decreased abduction and medial rotation
- positive trendelenberg
- may have associated genu valgum
What may cause coxa vara?
- primary defect in the endochondral ossification of the medial aspect of the NoF
What is ‘version’ in the femur?
“state of having been turned, deviated, oriented”
relates to the NoF and HoF which is normally turned or tilted towards the anterior aspect of the body (towards the frontal plane) by around 16 degrees (15-20)
What is anteversion?
- the NoF and HoF is turned or tilted further towards the anterior aspect of the body (towards the frontal plane)
- results in lateral rotation of the leg
What is retroversion?
- the NoF and HoF is turned or tilted away from the anterior aspect of the body
- results in medial rotation of the leg
What is torsion in the femur?
A structural, osseous state of twist in a bone along it’s longitudinal axis.
What is antetorsion?
- medial femoral torsion
- a medial twist of the distal end of the femur on the proximal end of the femur
- medially rotated thigh
What is retrotorsion?
- lateral femoral torsion
- lack of normal medial torsion or a true lateral twist of the distal end of the femur on the proximal end of the femur
- laterally rotated thigh
What is the normal amount of version/torsion in a newborn?
Version: anteversion = 60 degrees
Torsion: antetorsion = 30 degrees
Overall 30 degrees laterally rotated position of the hip
What is the normal amount of version/torsion in an adult?
Version: anteversion = 15-20 degrees
Torsion: antetorsion = 15-20 degrees
A position of anteversion and retrotorsion will result in…
a laterally rotated gait profile and retrograde pronatory forces through the foot
A position of retroversion and antetorsion will result in…
a medially rotated gait profile and either supinate type foot or splayed pronated foot type
How can torsion be corrected?
If torsion is great enough that it requires treatment then surgical reduction and fixation to derotate the femur is only option.
What happens if attempt to correct torsion by creating opposing torsion in the lower limb?
it will twist at the place of resistance e.g. the knee - can de-stabilise the knee
What is the assessment for femoral torsion?
Ryder’s Test
What is the Ryder’s Test?
Clinical measure of femoral torsion - best measure possible without using imaging.
Femoral torsion = Ryder’s finding +/- assumed amount of anteversion
What is Legg-Calve-Perthes Disease?
Idiopathic juvenile avascular necrosis of the HoF
What is the pathology of Legg-Calve-Perthes?
Repeated bouts of infarction and pathological #’s as a result.
3 stages - blood supply disrupted, softening and collapse of bone because of interrupted blood supply, and re-establishment of blood supply and some repair and remodelling of HoF
What is the result of Legg-Calve-Perthes?
Widening and flattening of the HoF - instead of spherical appearance
