Term
| what makes up 75% of the meniscus |
|
Definition
|
|
Term
| does articular cartilage or meniscus have more collagen |
|
Definition
|
|
Term
| describe the meniscus matrix |
|
Definition
|
|
Term
| is the meniscus matrix permeable to water |
|
Definition
| not very. It doesn't have a lot of water in it. |
|
|
Term
| how does the amount of GAGs in meniscus compare to GAGs in articular cartilage |
|
Definition
| 10% as many GAGs in meniscus than in AC = less glue and stiffness |
|
|
Term
| describe the meniscus structure overall |
|
Definition
| dense collagen structure, not as strong as articular cartilage |
|
|
Term
| where is the meniscus vascular and innervated in adults? |
|
Definition
|
|
Term
| should you try to repair a meniscus in a child and why |
|
Definition
| yes. There is a greater chance of vascularity and innervation in central portion of meniscus in children |
|
|
Term
| what are the cells like in the meniscus |
|
Definition
| 2 cell types that are between fibroblast and chondrocyte |
|
|
Term
| is it more common to see meniscal tears in younger patients or older patients |
|
Definition
| more common to see meniscal tears in older patients |
|
|
Term
| should you try to repair a meniscus in an adult and why? |
|
Definition
| blood supply is critical to healing response, the longterm survival of the meniscus, and the longterm health of the articular cartilage. Try to repair it. |
|
|
Term
| what is the structural organization of the layers of the meniscus |
|
Definition
| superficial layer - surface layer - middle layer - surface layer - superficial layer |
|
|
Term
| describe the superficial layer of the meniscus |
|
Definition
| fine collagen fibrils woven into a mesh matrix. Very thin. Resists tensile stress to prevent openings that could go deeper down into tissue |
|
|
Term
| describe the surface layer of the meniscus |
|
Definition
| irregularly aligned collagen bundles. |
|
|
Term
| why are the collagen bundles in the surface layer randomly aligned |
|
Definition
| to reduce stress between the superficial layer and middle layer |
|
|
Term
| describe the middle layer of the meniscus |
|
Definition
| large collagen bundles oriented in a circumferental fashion |
|
|
Term
| are there more circumferentially or radially directed fibers in the meniscus |
|
Definition
| more circumferentially directed fibers |
|
|
Term
| name some places in the body with meniscal fibrocartilage |
|
Definition
| knee, TMJ, sternoclavicular joint, vertebral facet joint, acromioclavicular joint, ulnar-carpal joint |
|
|
Term
| where might you find unwanted vestigial remnants of meniscus |
|
Definition
|
|
Term
| why are vestigial meniscal remnants in the ankle joint problematic |
|
Definition
| they can cause impingement and increase contact pressure. May require surgery to remove them. |
|
|
Term
| what is another name for the ulnar carpal joint |
|
Definition
| triangular fibrocartilage complex |
|
|
Term
| what are the functions of the meniscus |
|
Definition
| fill in space to increase contact area in order to decrease contact pressure. Protect articular cartilage from high contact pressure. |
|
|
Term
| what is at risk if you lose your meniscus |
|
Definition
|
|
Term
| what is the main job of the knee meniscus |
|
Definition
| attenuate pressure by increasing contact area |
|
|
Term
| what are secondary jobs of the knee meniscus |
|
Definition
| loadbearing mechanism, shock absorber (by deforming and prolonging loading time), joint stability (minor), joint lubrication |
|
|
Term
| what will happen if the knee ligaments and capsule fail |
|
Definition
| you are looking to have a meniscal injury soon. It is not designed to bear the brunt of joint stability. |
|
|
Term
| how does the meniscus help with joint lubrication |
|
Definition
| low μ between articular cartilage and meniscal fibrocartilage bathed in synovial fluid |
|
|
Term
| what might be the cause of pain in a patient who has deep pain in the joint that hurts with certain movement but not every time they do the movement |
|
Definition
| meniscus may have torn. The torn piece can go where it isn't supposed to be and cause increased contact pressure and increased pain. It could also be a chondral defect from a delamination injury. |
|
|
Term
| what to do when a patient has deep knee pain with certain movements some of the time |
|
Definition
| refer to orthopedist who will probably want to do an MRI |
|
|
Term
| is the distal femoral bone convex or concave |
|
Definition
|
|
Term
| is the proximal tibia convex or concave |
|
Definition
|
|
Term
| what happens to the knee meniscus when it is loaded in compression between the convex femur and the concave tibia? |
|
Definition
| it will be pushed to the periphery |
|
|
Term
| what keeps the meniscus in place in the knee? |
|
Definition
| the meniscus is tethered down by ligaments at the anterior and posterior horn |
|
|
Term
| what type of stress is on the meniscus as it is pushed out to the periphery between femur and tibia but pulled medially by attachments to anterior and posterior horn? |
|
Definition
|
|
Term
| what does the tensile stress want to do to the meniscus |
|
Definition
| the tensile stress wants to produce a transverse cut radially through the meniscus |
|
|
Term
| why do we not see a lot of transverse tears in knee meniscI? |
|
Definition
| collagen fibers are oriented circumferentially to reduce tensile stress and prevent a transverse tear |
|
|
Term
| what is the term for the circumferential lines of tensile stress |
|
Definition
|
|
Term
| what type of tear is more commonly seen in the meniscus? |
|
Definition
|
|
Term
| what is a bucket handle tear |
|
Definition
| longitudinal tear that causes a separation that looks like a bucket handle |
|
|
Term
| if there is a compression and twisting injury of the meniscus, what injury is likely to occur |
|
Definition
| longitudinal bucket handle tear |
|
|
Term
| why is it easy for a bucket handle tear to move in and out of place |
|
Definition
| it is still attached at anterior and posterior horns |
|
|
Term
| why should you take care of a bucket handle tear early |
|
Definition
| it can get bigger. Once it gets too big, it will have to be removed, and it will be a bigger piece that needs to be removed. |
|
|
Term
| how does not having a meniscus affect GRF through the body |
|
Definition
| not having a meniscus means you have more GRF through the body because the meniscus deforms to increase Δt and attenuate force. |
|
|
Term
| how does the meniscus provide joint stability? |
|
Definition
| it is like a door stopper preventing the femoral condyle from translating over it. |
|
|
Term
| if a ligament is ruptured and the femoral condlye does translate over the meniscus, what will happen? |
|
Definition
| shearing injury to the meniscus |
|
|
Term
| what is the meniscus' best friend? |
|
Definition
|
|
Term
| what is the job of a ligament |
|
Definition
| protect other joint tissues |
|
|
Term
| If an ACL injury is incurred and there is no meniscal lesion at the time of initial assessment, what might happen |
|
Definition
| get a meniscal tear later |
|
|
Term
| what should you do if you know that a person has ligament injury that has not been surgically repaired? |
|
Definition
| support knee with brace, reduce activity. It puts the menisci at risk when primary ligamentous or capsular restraints are injured |
|
|
Term
| describe joint lubrication at meniscus |
|
Definition
| fluid-film lubrication of synovial fluid |
|
|
Term
| how much contact area do you lose with a medial menisectomy |
|
Definition
|
|
Term
| what happens if you have a menisectomy |
|
Definition
| contact pressure goes way up. Peak pressures are confined to small areas, which are the first to get OA. Magnitude of OA is proportional to the amount of meniscus removed. |
|
|
Term
| what are conservative interventions for knee meniscal injury? |
|
Definition
| decrease WB for a few weeks, avoid extremes of ROM, enhance joint stability, attenuate GRF, weight loss |
|
|
Term
| why avoid extremes of ROM for damaged meniscus? |
|
Definition
| As the knee goes into extreme flexion, the femoral condyles will push anteriorly on the anterior horns of the meniscus, which will stress meniscal tissue. Same thing happens with extension and posterior pushing. |
|
|
Term
| how to enhance joint stability to reduce increased damage to meniscus? |
|
Definition
| dynamic strength, activity protection, bracing |
|
|
Term
| when to choose surgery for meniscus |
|
Definition
| tear in avascular region (can't heal on its own) |
|
|
Term
| how long to try conservative treatments before seeing an orthopedist |
|
Definition
|
|
Term
| what should be the surgical priority for meniscal repair |
|
Definition
| keep as much tissue as possible |
|
|
Term
| how is a meniscus repaired surgically |
|
Definition
| suture injured areas to vascular areas. |
|
|
Term
| what to do after meniscal surgery |
|
Definition
| NWB and protected ROM for 6 weeks |
|
|
Term
| why is it necessary to establish blood supply to injured avascular tissue and protect it afterward |
|
Definition
| facilitate healing, make it stronger, less chance of reinjury |
|
|
Term
| what are the 2 suture methods for surgical repair |
|
Definition
|
|
Term
| describe horizontal sutures |
|
Definition
| weak: can be pulled apart by tensile stress. |
|
|
Term
| describe vertical sutures |
|
Definition
| stronger: goes vertically around the meniscus and pulls it tight. Can do a double vertical suture = very strong. |
|
|
Term
| are all internal fixation devices for meniscus good? |
|
Definition
|
|
Term
| which internal fixation device for meniscal tear has greatest holding power |
|
Definition
|
|
Term
| what are some knee meniscus repair methods that you don't want a surgeon to use on your patient |
|
Definition
| horizontal suture, Biostinger, T-Fix Stitch, meniscus arrow, other stuff |
|
|
Term
| what is another thing to do to surgically promote healing in an injured meniscus? |
|
Definition
|
|
Term
|
Definition
| taking a large gauge needle that is hollow inside and making holes in the body of the meniscus from periphery to center every 5mm. This makes artificial blood vessels to carry blood from periphery to where lesion is. |
|
|
Term
| does trephination show good results in research? |
|
Definition
| yes. Started in dogs as a shallow cut. |
|
|
Term
| what is a surgical allograft implantation |
|
Definition
| meniscus + 2 attached bone plugs from cadaver into perfectly matched recipient. You drill holes for the bone plugs, the bone plugs go in and you get fracture healing, you suture around the periphery. |
|
|
Term
| does the cadaver and recipient's meniscus have to fit perfectly? |
|
Definition
|
|
Term
| what are guidelines for receiving a meniscus surgical allograft |
|
Definition
| physically active, younger than 55 (too young for TKA), missing more than 1/2 meniscus or unreparable tear, activity-related pain, no arthritis, skeletally mature, not obese, normal alignment, stable ligaments, compliant |
|
|
Term
| have surgical allograft implantations been around for a while |
|
Definition
|
|
Term
| are meniscal allografts permanent? |
|
Definition
| no. they buy you about 10 years before TKA |
|
|
Term
| how much does contact pressure increase if you have a menisectomy |
|
Definition
|
|
Term
| if you have an allograft, how much does contact pressure increase |
|
Definition
|
|
Term
| what happens if you don't use bone plugs for surgical allograft |
|
Definition
| meniscus moves too much. Just as bad as menisectomy |
|
|
Term
|
Definition
| outpooching along the joint line that feels soft and squishy. |
|
|
Term
| what causes a meniscal cyst |
|
Definition
| horizontal tear in the meniscus that permits synovial fluid and cells to migrate to the peripheral portions of the meniscus where they form a cyst along the joint line. |
|
|
Term
| is a lateral or medial meniscal cyst more common |
|
Definition
|
|
Term
| how to treat a meniscal cyst |
|
Definition
| drain to decompress or excise and repair meniscal lesion. |
|
|
Term
| what is a cyst a red flag for |
|
Definition
|
|
Term
| what is a meniscal pseudocyst |
|
Definition
| bulge along the joint line that results from a loose flap of meniscal tissue folding underneath adjacent meniscal tissue, thereby producing a joint line bulge without any fluid filled cyst formation. The bulge is just meniscus. |
|
|
Term
| what does a bulge around joint line indicate |
|
Definition
| possible meniscal tear. BNB |
|
|
Term
| what are two good indicators of meniscal tear |
|
Definition
| joint line tenderness + history |
|
|
Term
| what are 2 not so good tests for meniscal injury |
|
Definition
| McMurray's, Apley's Compression |
|
|
Term
| what are 2 new good tests for meniscal injury |
|
Definition
|
|
Term
| How to do Ege's test for medial meniscus |
|
Definition
| ask patient to get into hip ER in standing. Then ask for a squat. Then ask for return to standing with hip ER. |
|
|
Term
| how to do Ege's test for lateral meniscus |
|
Definition
| stand in IR (valgus). Squat. Return to standing. |
|
|
Term
| what are positives for Ege's |
|
Definition
| pain, giving away, clicking |
|
|
Term
|
Definition
| patient stands on one leg with knee flexed to at least 20 deg while twisting trunk side to side. |
|
|
Term
| where to stand with thessaly |
|
Definition
| behind to catch patient when she falls |
|
|
Term
| what is a positive for thessaly test |
|
Definition
| pain, giving away, clicking |
|
|
Term
| what is the unhappy triad? |
|
Definition
| ACL, MCL, medial or lateral meniscus: medial more likely with only ACL tear, but lateral more likely in combination with ACL tear |
|
|
