knee pathologies Flashcards
what is the MOI of patellar dislocations?
traumatic or autraumatic
what generally is seen in the case of a traumatic patellar dislocation?
high level of pain c/o hearing a sound rotation of knee on a fixed foot direct trauma knee flexed and varus stress
what generally is seen in the case of a atraumatic patellar dislocation?
-hyperlaxity of genu recurvatum leading HE of the knee
patella altra
increased Q angle
previous Hx of dislocations
on which side is the paterlla generally dislocated on?
lateral side
what is the pain site for patellar dislocations?
severe pain around the patella
if dislocation is not reduced, where is the patella generally located w/ flexed knee?
on the outside
is there presence of swelling w/ patellar dislocations?
yes, immediate, especially if traumatic
how is ROM in patellar dislocation?
aprehension w/ knee flexion and extension or w/ lateral patellar glide
how is RISOM w/ patellar dislocation?
ms inhibition, pain w/ quad contraction
how is palpation of patellar dislocation?
apprehension
pain on the medial border of the patella and medial PF ligament
what special tests can be used to detect patellar dislocation?
moving patellar apprehension test
when can the moving patellar apprehension test be performed?
once reduces, not immediately post injury
what tests/methods are use to diagnose patellar dislocations?
xray, CT, MRI which are used to R/O #
what may lead to recurrence of patellar dislocations?
patella alta
shallow groove
torn ligament
how is patellar dislocation treated?
conservative Rx for > 3 months
extension splint for ~2 weeks
increase in quad str
improvement of proprioception
what is the PFPS?
pain in the anterior knee
who is most likely to be affected by PFPS?
women
teens
what is the etiology of PFPS?
multifactorial
what are predicitors for poorer outcomes w/ PFPS?
Longer duration of Sx prior to Rx
overall poorer function
worse pain
are specific tests used to diagnose PFPS?
no, most test have low accuracy for PFPS
What are the criteria for diagnosis of PFPS?
The presence of retropatellar or peripatellar pain
AND
Reproduction of retropartellar or peripatellar pain w/ squatting, stair climbing, prolonged sitting, other functional activities loading the PFJ in a flexed position
AND
Exclusion of all other conditions that may cause AKP including tibiofemoral pathologies
how are PFP classified
in 4 sub categories 1. overuse/overload w/o other impairments 2. ms performance deficit 3. mvmt coordination deficit 4.mobility impairments
when are overload/overuse PFPS observed?
When pt present w/ Hx of increase load magnitude or frequency
when are muscle performance deficit PFPS observed?
When pt presents w/ decrease strength in hip ms or quadriceps
when are coordination derficits in PFPS observed?
-pt is asked to perform SL squat and dynamic knee valgus can be observed and isnt related to a decrease in strength
how to differentiate knee valgus due to decrease in strenght vs coordination?
MMT testing: test hip abd/ER and no weakness but still see dynamic knee valgus then it a motor control issue
when can mobility impairement for PFPS be observed?
pt presents w/ increased foot mobility and/or decreased flexibility in one of the following muscles; gastroc, soleus, lateral retinaculum, ITB
why will hypermobility of the foot lead to PFPS?
due to overpronation of the foot
why will hypomobility of the foot lead to PFPS?
decreased flexibility of the muscles in the involved area
what are the most important risk factors for pt w/ PFPS?
- physically active
- weak quad esp in military populations
- quad athrophy?
- dynamic knee valgus
what factors can be associated w/ the development of PFP?
age body mass height BMI static Q angle in NWB and WB
what factors may lead to abnormal patellar tracking and hence PFPS?
Abnormal alignment of LE
Stiffness, tightness of structures around the patella
Weakness of structures around the patella and in the LE kinetic chain
what are possible anatomical factors which may lead to PFPS?
Femoral anteversion (hip section) Knee valgus Tibia ER or tibial tubercle laterally positioned Patella alta Shallow groove (lower lateral groove)
what dynamic factors leading to possible PFPS can be Rx w/ physio
-increase dynamic knee valgus by increase add/IR of the hip and abd/ER of the knee during WB
what may cause the increased dynamic knee valgus in the knee?
weak hip extension, abd, ER
decreased hip ER rom
LE motor control deficits
foot hyperpronation
what is FPPA?
Frontal plane projections; 2d surrogate for a 3d measure of hip add, IR, knee ABD, ER
FPPA is the angle b/w which two lines
ASIS to midpoint of TF joint and midpoint of TF joint to midpoint of ankle mortise
when measuring FPPA changes from what to what are assessed?
change in FPPA from start position to the point of peak knee flexion
what is considered as dynamic valgus w/ a change in FPPA
more than 10 degrees in the positive direction
what is considered as dynamic varus w/ a change in FPPA
more than 10 degrees in the negative direction
what happens if there is less than 10 degree change in FPPA in either directions (+/-)
no change
what muscles stiffness may be associated w/ PFPS?
rectus femoris
ITB
hamstring
calf
what stiff muscle will lead to an excessive superior force on the patella esp w/ knee flexion
rectus femoris
what stiff ms will cause excess lateral force on the partella and can ER the tibia
ITB
what stiff ms will cause knee flexion and thus increase the pressure at the PF joint?
hamstring and calf
what happens in the event of a tight calf?
decreased DF in the midstance leading to increased foot pronation and thus to compensate increase in knee valgus and will pull the patella laterally
what happens if the lateral retinaculum of the knee is tight?
pulls the patella laterally and wiull change the tracking of the patella and cause changes in force where they shouldnt be present
what is the MOI for PFPS?
AKP w/ activity associated w/ increased load that the PF joint
what is the pain site for PFPS?
Ant knee pain, retropatellar and peripatellar pain
what is the pain type associated w/ PFPS
may c/o catching sensation but usually poorly defined pain quality
what is the pain pattern associated w/ PFPS?
activities causing an increase in load at the PF joint, especially w/ flexed knee position will lead to increase pain
what are general observations associated w/. PFPS?
quad Athrophy foot hyperpronation FH anteversion knee valgus patellar position; lateral shift or patella Alta
what functional tests may be performed to assess for PFPS
SL squat, step downs, or lateral stepdowns and FPPA can be assessed andf look for signs of hyperpronation
full squat to assess for pain in flexion and at EOR
trendelenberg to detect glute med weakness to assess for tension on ITB
how is the knee ROM in PFPS?
Generally not an issue, if tight anterior structures, knee flexion may be limited
how is hip ROM w/ PFPS?
decrease hip ER is possible
how is PROM of the patella?
glides will be Ax for stiffness
medial glide might be decreased due to increased stiffness of ITB or lateral retinaculum
inferior glide might be decrease due to stiffness of rectus femoris
how is RISOM w/ PFPS?
weakness of hip extensors hip abductors hip ER knee extensors hipSIT
how is palpation w/ PFPS?
Assess for pain around the patella
what can be observed w/ flexibility Ax in PFPS
Stiffness Ax hamstring 90-90 or SLR gastroc and soleus w/ DF in wb w/ knee straight or bent rectus fem w/ modified thomas test ITB w/ ober's or modified thomas test
what are special tests that can be performed top assess for PFPS?
Patellar tilt test where the lateral aspect of the patella can not go beyond the horizontal
what is suggested CPG for overuse or overload PFPS?
Eccentric step down test
what are the suggested CPGs for muscle performance deficits in PFPS?
hipSIT and MMT of thigh ms
what are the suggested CPGs for mvmt coordination deficits in PFPS?
dynamic valgus on lateral step down test
frontal plane valgus in SL squat
what is the suggested CPG for hypomobility in PFPS?
patellar tilt test
flexibility test: HS, gastroc, soleus, ITB, quads
ROM: hip IR/ER
what is the suggested CPG for hypermobility in PFPS?
foot mobility test
foot posture index
what are some self reported outcome measures
VAS or NPRS for pain
validated questionaires s/a anterior knee pain scale, PF pain and OA subscale of knee injuries and OA outcome scores
ENG and pierrynosku questionnaire
what is the goal of Rx for PFPS?
decrease compression on PF joint during daily activities
how can compression on the PF joint be decreased?
decrease in jt rxn force
decrease in pain, irritation and inflammation
center the patella w/in the trochlea
is PFPS a self limiting condition
no
education about what is essential in PFPS?
load management BW management importance of adherence to active Rx evidence regarding Rx options kinesiophobia education to improve compliance and adherence
what may be used for pain management in cases of PFPS?
- Reduction and removal of aggravating factors/activities
- taping for ST correction of patella position and decrease in PF stress
- foot orthosis in cases of hyperpronation
- biophysical agents
what are the CPGs associated w/ foot orthosis in the case of PFPS?
- Prescribed in pts w/ greater than normal pronation allowing for ST reduction in pain
- prescribed w/ exercise program
- NSAIDS
which biophysical agents should not be used to reduce pain in pts w/ PFPS?
US phonophoresis iontophoresis estim laser