Knee meniscal issues Flashcards
T or F
Meniscectomy does not impact risk of knee OA development
False. It does
What are 6 primary functions of the meniscus?
- load transmission; spreads loading over a larger area
- shock absorption
- joint stability
- joint nutrition
- joint lubrication
- proprioception
What portion of the menisci have a blood supply?
How does the rest of the meniscus get nutrition?
- the outer 10-30% has a blood supply in an adult
- diffusion of synovial fluids
Menisci are made up of ___% water
65-70%
Menisci are thick _____ and thin ______
thicker peripherally, thinner centrally
Describe the following for the lateral meniscus:
- shape
- relative size
- relative mobility
- muscle attachments?
- ligament attachments?
o Shape: 4/5s of a circle
o Smaller and more mobile than the medial (~10 mm of movement)
o Muscle attachment: directly popliteus muscle aids in stability
- attached to LCL
Describe the following for the medial meniscus:
- shape
- relative size
- relative mobility
- muscle attachments?
- ligament attachments?
o Shape: “C-shaped”
o Larger and less mobile (~2 mm of movement)
o Muscle attachment: indirectly w/ the semimembranosus
o More attachments to the joint capsule, limiting translation and mobility compared to the lateral side
- attached to MCL
Does the lateral or medial femoral condyle rotate more?
- lateral needs to rotate a bit more
What nerve innervates the menisci?
- common peroneal n (reccurent peroneal branch)
The anterior/posterior horns are stressed in what positions?
- extremes of flexion and extension
T or F;
PTs can consistently differentiate between acute vs chronic meniscal tears
- F
____% of pts with symptomatic OA also had meniscal tears
- 91%
Is the medial or the lateral meniscus more often injured?
- medial
The lateral meniscus has a higher incidence of injury in what population?
- younger/athletic
Is gender associated with meniscal injury?
- yes; more often in females
What are the characteristics of most meniscal injuries? (4)
- closed-chain
- high shear forces
- more often non-contact
- generally with a foot planted and twisting
The medial meniscus often is injured at the same time as what other two structures?
- MCL
- ACL
Is an acute dx of meniscal tear right after injury typically valid?
- if just clinical exam, no. Too much pain, swelling, irritability to differentiate structures at that point.
What should be done with palpation of the joint line when examining for a suspected meniscal tear?
- palpate w/ medial/lateral rotation, tibfem loading and ER/IR
Should you be able to differentiate between the joint line and meniscus itself with palpation?
- yes
What are 3 standard provocation tests for meniscal tear?
- McMurray’s
- Thessaly
- Apley’s compression
What 2 ROMs should Thessaly be done at?
- 5* and 20* flx
Is examining dynamic control more or less of a concern in younger patients w/ meniscal defects?
- less of a concern. With chronic degenerative tears, some stability is lost, thus dynamic stability will be more important to quantify on exam
Do you expect quad lag with older patients with chronic knee pain?
- yes. quad weakness is common with chronic knee pain, often overtly demonstrated w/ quad lag
What are the criteria for the Ottawa knee rules for imaging after acute traumatic injury? (6)
o Over the age of 55
o Unable to take more than 4 steps immediately after injury or in the ED
o Isolated patellar tenderness (w/o other bony tenderness)
o Tenderness of fibular head
o Unable to flex knee to 90*
What type of imaging is most sensitive to rule out meniscal injury?
- MRI
T or F
There is a relatively high rate of meniscal tears in asymptomatic individuals
- T; usually older adults
What are the general recommendations for management of acute meniscal injury?
- relative rest; activity limitation
- RICE
- gentle ROM and isometrics after 72 hours
What are the primary considerations for therex with meniscal injury? (2)
- limit excessive end range flexion; especially with high load
- minimize tibial rotation
Is it ok to be loading the meniscus during it’s recovery?
- yes; regular force on the meniscus is necessary for proper healing
What’s the minimum length of time recommended for a meniscal return to activity program?
- 6 weeks; can be longer
What is the goal of management for chronic meniscal tears?
- improving motor control and motor stability to decrease stress on the meniscus
At 2 years, is TKA better than PT for pts with OA, or with OA and meniscal tears?
- nope. Not according to medbridge
A meniscal tear in the “white white zone” has a (good/poor) prognosis for healing?
- poor; avascular region
What test has the highest sensitivity to rule out medial meniscal tear?
- joint line sensitivity
What special test can be used to indicate which meniscus is injured?
- McMurray’s; pain with medial tibial rotation is associated with lateral meniscal injury, medial tibial rotation assocaited with lateral meniscal injury
