knee Flashcards
knee rom
flexion 135
extension 0
knee open pack
flexion 25
knee closed pack
full extension
ER
actions of sartorius muscles
hip - flex, weakly abduct, laterally rotate the femur
knee - flex the leg;
when the knee is flexed, medially rotates the leg.
when does the screw home mechanism occur? why does it occur?
During the last 20 or 30 degrees of knee extension, the tibia (open chain) ER or
femur (closed chain) IR ~10 degrees.
Why - slight rotation is due to inequality of the articular surface of femur condyles - medial condyle larger.
Rotation must occur to achieve full extension and then flexion from full extension - lock and unlock knee
what tests used? what pathology?
- knee pain following a twisting injury while landing from a jump while playing soccer
- patient’s knee is swollen significantly and is unable to jump or run.
- ACL
- majority of injuries to female soccer players is to the ACL, especially with a running/twisting injury and swelling.
- Pivot shift - 81.8% sensitive and 98.4% specific.
- Lachman’s test- 81.8% sensitive and 96.8% specific
- Anterior drawer sign - 40.9% sensitive and 95.2% specific
what deg flexion with eccentric loading, the point of the greatest compression of the patella into the femur?
if pain, what pathology?
30 deg flex
Patellofemoral pain syndrome
common complication post ACL repair
loss ROM
Arthrofibrosis following ACL repair is the MOST common complication, limiting range of motion.
what pathology?
Mild pain or tightness in the hamstring muscle, especially when stretched or contracted.
grade I mild hamstring strain
what pathology?
Immediate pain with injury, painful with stretching, and significant bruising over the hamstring.
grade II, moderate hamstring strain, partial tear
what pathology?
Burning pain immediately after injury, inability to walk, and significant bruising over the hamstring.
grade III, severe hamstring strain, complete tear
most dangerous point of rehabilitation is approximately # weeks when the graft is remodeling?
6 weeks
what medication?
first several weeks post TKA
- precautions?
Warfarin, common anticoagulants
- require frequent blood tests and his diet will require close supervision
Trauma to the tibial nerve
- motor
- sensory
weaken plantarflexion and alter sensation of the plantar surface of the heel.
Gliding the proximal phalanx which direction?
will improve the 1st MTP joint extension
dorsally
concave surface glides in same direction as roll
knee flexion needed for gait, what phase?
0-60 Initial swing
knee flexion needed for gait
83-107
knee extension needed for gait, what phase?
0
midstance - terminal stance
terminal swing - initial contact
what test?
- Patient supine with the knees extended.
- Therapist applies slight pressure distally with the web space of their hand over the superior pole of the patella and asks the patient to contract the quadriceps muscle.
- Positive test: failure to complete the contraction without pain.
Clarke’s sign
may be indicative of patellofemoral dysfunction.
MMT what muscle?
- Patient prone, knee is flexed to 50-70 degrees with the thigh in slight lateral rotation and the leg in slight lateral rotation on the thigh.
- Therapist applies pressure against the leg, proximal to the ankle, in the direction of knee extension.
biceps femoris
What test? what for?
-Patient in supine with the knee flexed to 90 degrees and the hip flexed to 45 degrees.
anterior drawer test - ACL injury
What test? what for?
Patient in supine with the knee flexed to 90 degrees and the hip flexed to 45 or 90 degrees. The test is often positive in the presence of a posterior cruciate ligament injury.
posterior sag sign - PCL tear
What test? what for?
Patient prone. Therapist passively flexes the patient’s knee through the available range of motion.
Positive test is indicated by spontaneous hip flexion and may be indicative of a rectus femoris contracture.
Ely’s test
what term? greater in women or men? increased value associated with? abnormal?
measurement of lateral line of pull of the quadriceps relative to the patella is referred to as
Angle formed by 2 lines. One line connecting from the anterior superior iliac spine to the middle of the patella and the other connecting from the middle of the patella to the tibial tuberosity.
Q-angle -females is between 13-18° -increased Q angle: Femoral anteversion External tibial torsion Laterally displaced tibial tubercle Genu valgum: increases the obliquity of the femur and concomitantly, the obliquity of the pull of the quadriceps -abnormal value: risk of developing chondromalacia patellae, patella alta or mal-tracking of the patella.
what test? why?
medially rotated tibia position with an applied valgus force to the knee
assess anterolateral rotational instability of the knee
often used as part of the examination of a patient with a suspected ACL injury.
what test? why?
- patient lying supine and support the patient’s foot or ankle.
- Therapist competely flex the knee and allow the knee to passively extend.
- Normally, knee should extend completely, or “bounce home” into extension.
- Positive: extension is not complete.
knee menical lesion
pathology?
inflammation of the bursa located at the common insertion of the tendons of the sartorius, gracilis, and semitendinosus muscles on the anteromedial portion of the superior tibia.
- typically report pain just distal to knee, medial side tibia
Pes anserine bursitis
pathology?
- cyst in posterior knee, often associated with arthritis or a cartilage tear.
- Discomfort is typically reported in the posterior knee and is often exacerbated by extremes of flexion or extension.
Baker’s cyst, also referred to as a popliteal cyst, refers to a fluid filled cyst that develops in the posterior knee.
pathology?
caused by repetitive tension to the patellar tendon over the tibial tubercle in young athletes.
Knee pain is typically reported over the patella tendon at the insertion on the tibial tubercle.
Tibial apophysitis, Osgood-Schlatter disease
what pathology?
- Effusion and bruising may be minimal as bleeding may diffuse into soft tissues rather than the joint space.
- compared to the unaffected limb, pronounced laxity will be noted during valgus stress testing with the knee slightly flexed (e.g., >10 mm of medial gapping),
grade III MCL sprain, Complete rupture
Medial gapping when knee extended during valgus stress test typically indicative of additional injury (e.g., anterior cruciate ligament sprain).
what pathology?
- pronounced pain and tenderness to palpation medial knee
- bruising and effusion may be somewhat variable.
- compared to the unaffected limb, significant laxity will be noted during valgus stress testing with the knee slightly flexed (e.g., 5 to 10 mm of medial gapping).
grade II MCL sprain
what pathology?
- tenderness to palpation,
- minimal bruising, and effusion.
- compared to the unaffected limb, no significant difference will be noted during valgus stress testing with the knee slightly flexed.
grade I sprain of the MCL
what does 10 degree extension lag mean?
what causes it?
passive knee extension is 10 deg greater than active knee extension
- Inhibition of the quadriceps is a common rationale, including pain and effusion.
what pathology?
- general term describing pain or discomfort in the anterior knee
- repetitive overuse disorder resulting from increased force at the patellofemoral joint.
- mistracking of patella within intercondylar groove, typically lateral tracking
- associated with muscle tightness, muscle imbalance, excessive pronation, increased Q angle, knee hyperextension, and inherent patellofemoral joint characteristics
- pop usually younger, recreational runners, women
- knee pain with prolonged sitting with knee flexion, going down stairs, squatting, jumping
- occasional buckling of knee
Patellofemoral syndrome, runners knee, movie goers knee
what pathology?
softening of the articular cartilage of the patella
chondromalacia patella
what impact does increased Q angle have on knee?
increased angle alters the quadriceps line of pull in such a way that the patella tends to track more laterally along the femoral groove.
possible interventions for Patellofemoral syndrome?
- orthotic arch support to correct pronation
- Patellar taping to improve patellofemoral alignment to use during strengthening
- VMO strengthening
biceps femoris action?
both heads: flex and laterally rotate the knee joint.
long head also extends and laterally rotates the hip joint.
biceps femoris
origins?
insertion?
long head origin: ischial tuberosity
short head origin: linea aspera of femur Both heads insert: lateral side of the head of the fibula.
Anterior trunk bending during foot flat phase reason?
intervention?
anterior trunk bend- commonly used to bring the line of force in front of the knee to compensate for weak knee extensors
- strengthen quads
Triceps surae weakness during gait?
can result in inadequate knee extension in stance
what is likely injured?
- knee flexed and object forcefully strikes proximal anterior tibia displacing it posteriorly
- MVA dashboard injury, athletics, falling up the stairs
PCL
what is likely injured?
- noncontact deceleration producing valgus twisting injury eg. athlete quickly pivoting in opposite direction
- hyperextension
- severe medial tibial rotation
ACL
what is likely injured?
- lateral patellar dislocation during powerful contraction of quad in combo with sudden flexion and external rotation of tibia on femur
medial patellofemoral ligament
what is likely injured?
- severe trauma resulting in dislocation of tibia on femur
- fracture distal femur with posterior displacement of short distal fragment
popliteal artery
what is likely injury?
- pain over lateral knee due to irritation of distal portion IT band as it rubs against lateral femoral condyle
- overuse injury with repetitive flexion and extension of knee
- common in long distance running athletes
IT friction syndrome
