Placebo/hip Flashcards
What was the finding of Gracely et al (1985) in the effect of patient and practitioner expectation wrt placebo?
Clinical analgesia depends not only on physiological action of the treatment administered but also on the expectations of the patient and clinician
Buske-Kirschbaum et al (1992) were able to increase NK cell activity after exposing rats to sherbet. How did they do it? What important conclusion did they draw?
Classical conditioning - repeatedly paired sherpet with subcut injection of epinephrine. Eventually tried with saline instead of epinephrine and same increase in NK cells was seen
Conclusion: placebo can modify the immune response
Kalauokalani et al (2001) studied the impact of patient expectation on outcomes of treatment with acupuncture and massage. What did they find? What implications does this have on clinical research?
If you got the treatment you thought would be better for you, you did better than if you got the treatment you didn’t think would be better for you.
Implications: method of recruitment (eg. from surgeons vs chiro office) could have large effects on patient outcomes.
What type of joint is the hip joint?
Diarthrodial ball and socket
What are the 3 degrees of freedom of the hip joint?
Flex/ext
Abd/add
Med/lat rotation
Name for the portion of the acetabulum which is covered by hyaline cartilage
Lunate surface
What does the transverse acetabular ligament do?
Forms the inferior surface of the acetabulum
Connects two ends of the horseshoe-shaped lunate surface
What is the central edge angle/angle of Wiberg? What is a normal range?
A line connecting the lateral rim of the acetabulum and the centre of the femoral head
Normal: 22-43 degrees
A decreased central edge angle indicates increased risk of ____________________
Superior dislocation
True or false: CE increases with age, so kids’ hips are less stable
True
Which imaging modality can be used to assess acetabular anteversion? What is a normal measurement?
CT or MRI
18.5deg in M, 21.5deg in F
pathological increase in the acetabular anteversion angle can result in increased risk of ____________________
Anterior dislocation
What is the femoral neck orientation? (3 directions)
Medial, superior, anterior
What is the angle of inclination? What is its purpose?
angle between neck and shaft of femur
Causes the greater trochanter to lie at the ntre of the femoral head
What is a normal angle of inclination in babies? In adults?
150deg
125deg
What is the name for a pathological increase in the angle of inclination? Pathological decrease?
> 135deg: Coxa valga
<120deg: Coxa vara
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The angle of inclination is somewhat ___________ in women due to the increased ________________
Smaller; pelvic width
Explain how coxa valga is associated with:
- knee OA
- hip OA
- osteoporosis of the femoral neck
- hip joint dislocation
Knee OA: causes genu varum, increasing compression on medial aspect of knee
Hip OA: more stress at superior/medial aspect of femoral head
Osteoporosis of the femoral neck: decreased tension forces going through neck of the femur
What is the MC cause of coxa valga?
Neuromuscular disorders (cerebral palsy, polio), skeletal dysplasia, JIA
In individuals with coxa valga, which muscle group needs to work much harder? Why?
Abductors - moment arm between head of femur and trochanter is much shorter
What compensation is commonly seen in the gait of individuals with coxa valga? Why?
Lateral trunk bending towards stance leg. Helps decrease the moment arm of the trunk, decreasing the overall amount of the force needed to be opposed by the hip adductors
An angle of inclinationof less than 90 degrees is known as a _______________ deformity and is associated with _______________ __________________, ________________, and _________________
Sheppard’s crook
Osteogenesis imperfecta
Pagets
Osteomyelitis
Which hip deformity increases the risk of developing SCFE? Why?
Coxa vara
Increased bending moment of femoral neck places shear forces through epihpyseal plate
What is the name for the angle between the axis of the femoral neck and axis of the femoral condyles? What is considered normal in newborns? In adults?
Angle of torsion
40deg in newboarns
8-30deg in adults
A pathological increased in the angle of torsion is called _____________, where a decrease is called ______________
Anteversion
Retroversion
In order for the femoral head to find congruence, the tibia rotates _____________ in anteversion, causing a ______________ gait and ___________ in retroversion, causing a _____________ gait
Internally. toe-in
Externally, toe-out
In a neutral standing position, which aspect of the femoral head is exposed? Which 3 deformities can cause more of the femoral head to be exposed?
Anterior and superior
Coxa valga, femoral anteversion, decreased centre edge angle
What are the 3 main ligaments of the hip joint? Which motions do they each oppose?
Pubofemoral ligament: abduction and extension
Iliofemoral (Y) ligament: hyperextension, adduction (superior fibres), abduction (interior fibres)
Ischiofemoral ligament: extension
What is the closed pack position of the hip?
Position where all ligaments are at their tightest.
Extension, abduction, medial rotation
What is the position of maximum congruence of the hip?
Frog leg - abduction, flexion, external rotation
True or false: the position of maximum congruence in the hip is also the position of maximum stability
False: max congruence is abd + flex + ext rot, max stability is abd + ext + int rot
This is probably the only joint in the body where they are different!
Moment generation by the hip muscles is best with (eccentric/isometric/concentric) contractions
Eccentric
What is passive insufficiency? How does this affect the hip joint?
Restricted ROM due to passive structures
Knee flexion causes reduced hip extension
Knee extension causes reduced hip flexion
What is active insufficiency?
Restricted muscle power due to the position of the joint causing muscle shortening. Caused by too much overlap in actin-myosin
Which hip flexor muscle is affected by active insuffiency? Explain
Rec fem
If knee extended and hip flexed, muscle shortens to the point where it can’t generate force
Sartorius, like rec fem, crosses both the hip and knee joints. Why is it not affected by active insufficiency?
Very long so position of knee has a very small effect on the proportional length change
In which position does glut max have the least ability to generate force?
Hip flexion (beginning of stance phase) Moment arm shortened
What are the 2 major abductors of the hip? Which 2 muscles assist them?
Major: Glut med + min
Minor: Sup. fibres of glut max + TFLq
Anteversion will cause a(n) (increase/decrease) in internal rotation and a(n) (increase/decrease) in external rotation of the hip
Increase; decrease
Children general start out (ante/retroverted) which is why they usually toe-(in/out)
Ante; in
Weakness of which muscle will predispose elderly individuals to femoral neck fractures? Why?
Glut med
Without glut med, body weight will bend the neck of the femur, placing tension on the superior side of the femoral neck
Glut med neutralizes this tension by compressing the superior fem neck
In order to bend so that your trunk is perpendicular to the floor, your hip joint needs to bend to <90deg. Why?
To shift COM further backwards, allowing COM to shift over base of support
How do the hip joints compensate for leg length changes during walking gait?
- Swing leg drops to reduce elevation of COM - Stance hip adducts and swing limb abducts to keep femurs perpendicular to ground
- Stance hip internally rotates while swing hip externally rotates to keep toes pointing forward
According to Avman et al (2019) a decrease in which hip range of motion was most strongly associated with NSLBP?
Internal rotation
According to Flynn & Fritz (2002), which 5 factors impact the likelihood of successful resolution of LBP from SMT? How many factors are needed for 95% success?
- Segmental hypomobility/pain upon spinging palpation over lumbar facets
- Acute onset of pain <16d
- No pain distal to knee
- At least 1 hip internal rotation >35deg
- Low fear avoidance beliefs score
What is a 95% confidence interval?
an interval that one is 95% confident includes the population mean (eg. 0.25 - 0.75)
If the confidence interval is 0.25 - 0.75, what does this mean about satistical significance?
Result is statistically significant because the interval has a lower limit above 0
Movement between 2 objects can be categorized into which 3 groups? Which 2 are seen in the knee joint?
