MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.
-
Upload
alex-gerner -
Category
Documents
-
view
226 -
download
0
Transcript of MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.
![Page 1: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/1.jpg)
MENISCI
![Page 2: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/2.jpg)
![Page 3: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/3.jpg)
histology
Water( 75%)
Collagen type 1
Proteoglycans
elastin
![Page 4: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/4.jpg)
Collagen fibers
Circumferential fibers(majority)
Radial fibers
Perforating fibers
![Page 5: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/5.jpg)
Role of hoop tension in menisci. Hoop tensiondeveloped in menisci acts to keep them between bones
![Page 6: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/6.jpg)
Radial tear eliminates hoop tension and damages meniscus function
![Page 7: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/7.jpg)
Anatomy
• Attached to the capsule except where the popliteus tendon is interposed laterally
• Loosely attached to the tibial plateaus by the coronary ligaments
• Avascular except near their peripheral attachments
![Page 8: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/8.jpg)
![Page 9: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/9.jpg)
![Page 10: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/10.jpg)
![Page 11: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/11.jpg)
![Page 12: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/12.jpg)
![Page 13: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/13.jpg)
Vascular supply
• lateral and medial geniculate vessels
• depth of peripheral vascular penetration is 10% to 30% of the width of the medial meniscus and
• 10%to 25% of the width of the
lateral meniscus
![Page 14: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/14.jpg)
![Page 15: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/15.jpg)
![Page 16: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/16.jpg)
FUNCTIONA. act as a joint
filler, compensating for gross incongruity between femoral and tibial articulating surfaces
B. prevent capsular and synovial impingement during flexion-extension
![Page 17: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/17.jpg)
function• joint lubrication• helping to distribute synovial fluid• nutrition of the articular cartilage• Stability especially rotary stabilizer• smooth transition from a pure hinge
to a gliding or rotary motion as the knee moves from flexion to extension
![Page 18: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/18.jpg)
![Page 19: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/19.jpg)
Load bearing
• Cover 1/2-to 2/3 of the articular surface
• Carry40%-70% of weight force
• medial meniscus 50%
• Lateral meniscus 70%
![Page 20: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/20.jpg)
![Page 21: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/21.jpg)
Effects of meniscectomy
Medial meniscectomy
↓contact area by 70%
↑contact stress by 100%
![Page 22: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/22.jpg)
Meniscal movement• The menisci follow the tibial condyles
during flexion and extension• during rotation they follow the femur
and move on the tibia• Medial meniscus:Ant /Post attachments
follow the tibia, but its intervening part follows the femur and becomes distorted
• Lateral meniscus:is firmly attached posteriorly and less likely to be injured
![Page 23: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/23.jpg)
![Page 24: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/24.jpg)
Meniscectomy and joint laxity
• Intact ligaments→little joint laxity
• Ligamentus insufficiency→↑joint laxity
• ACL insufficiency→forces in the medial meniscus increase significantly
• ACL insufficiency+medial meniscectomy:↑AP translation
• ACL insufficiency+lateral meniscectomy:↕AP translation
![Page 25: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/25.jpg)
MECHANISM OF TEAR
• rotational force while the joint is partially flexed
• vigorous internal rotation of the femur on the tibia results in meniscal catching
• meniscus torn longitudinally when the joint is suddenly extended
![Page 26: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/26.jpg)
![Page 27: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/27.jpg)
![Page 28: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/28.jpg)
![Page 29: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/29.jpg)
meniscaltears
• Longitudinal: The most common type usually involve the posterior segment Most involve the inferior rather than . . the superior surface medial meniscus ≈ lateral meniscus• Horizontal/oblique/radial usually lateral meniscus Usually between middle and anterior third
![Page 30: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/30.jpg)
Predisposing factors
• Degeneration• Cyst• Discoid meniscus• Ligament or muscle insufficiency• Knee instability• Abnormal mechanichal axes
![Page 31: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/31.jpg)
![Page 32: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/32.jpg)
DIAGNOSIS• History:• may not be obtained, especially when
tears of abnormal or degenerative menisci in a middle age person
• Locking or no locking: may not be recognized consider absence of normal recurvatum Usually only with longitudinal bucket handle tear• R/O pseudolocking
![Page 33: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/33.jpg)
Giving way
• Is not especific• Results from: Muscle(quadriceps) insufficiency Patellar problems Instability Loose body
![Page 34: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/34.jpg)
Giving way
Giving way due to
meniscal tear
•On rotary movements•With a feeling of subluxation or knee jumping
Giving way due to other
causes
•During flexion against resistance•Walking down stairs
![Page 35: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/35.jpg)
Effusion
• Acute: usually denotes a hemarthrosis, and it can occur when the vascularized periphery of a meniscus is torn
• Late: Tears occurring within the body of a meniscus or in degenerative areas may not produce a hemarthrosis
![Page 36: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/36.jpg)
signs• Quadriceps atrophy
• Joint line tenderness localized to posterolateral or posteromedial(the most important physical finding)
• Tears of one meniscus can produce pain in the opposite compartment of the knee. This is most commonly seen with posterior tears of the lateral meniscus
![Page 37: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/37.jpg)
Mc murray test• Palpate posteromedial/ posterolateral• Rotate leg external or
internal• Move knee from full
flexion to extension• Before 90˚→posterior horn• After 90˚→mid/ant horn
![Page 38: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/38.jpg)
Apley grind testCheck menisci during compression
![Page 39: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/39.jpg)
squat testPain localized to joint line is more important than pain during ext/int rotation
![Page 40: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/40.jpg)
Thessaly test• Knee in 5˚ and
20˚ flexion• Accuracy rate
95%• Always done on
the normal knee first to teach the pt
![Page 41: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/41.jpg)
![Page 42: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/42.jpg)
paraclinic
• X ray: routine AP/LAT/intercondylar/sky line views
• Arthrography• MRI: sensitivity →65% specificity→95%
accuracy→85%
![Page 43: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/43.jpg)
NONOPERATIVE MANAGEMENT
cylinder cast or knee immobilizer worn for 4 to 6 weeks
Strengthen muscles around the knee as well as the hip
![Page 44: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/44.jpg)
criteria
• ZONE• TEAR TYPE• CHRONICITY• SIZE(cm)
![Page 45: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/45.jpg)
A suitable candidate
• NonChronic• Stable( incomplete or could not be displaced
more than 3 mm from the intact peripheral rim)
• Peripheral• <5mm• no other pathological condition
![Page 46: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/46.jpg)
![Page 47: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/47.jpg)
Reparability of Meniscal Tears
• ZONE• TEAR TYPE• CHRONICITY• SIZE(cm)
![Page 48: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/48.jpg)
Ideal indication
• Acute• 1- to 2-cm• Longitudinal• Peripheral• young individual• in conjunction with anterior cruciate
ligament reconstruction
![Page 49: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/49.jpg)
![Page 50: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/50.jpg)
Open or arthroscopic repair
• Open:• posterior horn peripheral tears if posteromedial or
posterolateral capsular reconstructions are being done concurrently
• Arthroscopic: • lateral meniscus• necessary for tears at or near the junction of the vascular and
avascular zones• Medial menisci tears that extend deep to the collateral ligament
![Page 51: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/51.jpg)
DO NOT FORGET• For younger,active patients,ligamentous
stabilizationshould accompany meniscal suture because of thedecreased likelihood of healing and increased risk of re-rupture in a knee with ligamentous laxity
![Page 52: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/52.jpg)
![Page 53: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/53.jpg)
MENISCECTOMY
• Increasing degenerative changes were noted, especially after total meniscectomy
• After subtotal excision degeneration is localized
• degenerative change directly proportional to the amount of meniscus removed
![Page 54: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/54.jpg)
Complete or incomplete
• Complete removal of the meniscus is justified only when it is irreparably torn
• Total meniscectomy is no longer considered the treatment of choice in young athletes
• Subtotal excision is easier by arthroscopy
![Page 55: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/55.jpg)
LATE CHANGES AFTER MENISCECTOMY
• meniscectomy often is followed by degenerative changes within the joint
• after partial medial meniscectomy 88% to 95% of patients reporting good to excellent results.
![Page 56: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/56.jpg)
AUTOGRAFTS AND ALLOGRAFTS• Indications: skeletally mature too young for TKA significant pain and limited function conservative therapy failed mechanical tear no synovial disease younger than 40 years normal mechanical alignment stable knee Outerbridge grade I or grade II articular cartilage changes pain localized to the affected compartment
![Page 57: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/57.jpg)
AUTOGRAFTS AND ALLOGRAFTS
• Contraindications knee instability
varus-valgus malalignment
advanced osteoarthritis is an absolute contraindication
![Page 58: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/58.jpg)
questionsremain about their survivorship and function
![Page 59: MENISCI. histology Water( 75%)Collagen type 1Proteoglycans elastin.](https://reader035.fdocuments.us/reader035/viewer/2022081508/56649c925503460f9494d777/html5/thumbnails/59.jpg)
THE END