Why does a meniscus form? Why a meniscus occurs
Water molecules are attracted to the molecules in the wall of the glass beaker. And since water molecules like to stick together, when the molecules touching the glass cling to it, other water molecules cling to the molecules touching the glass, forming the meniscus.
What is upper meniscus and lower meniscus?
A meniscus is a curve formed on the upper surface of a liquid inside a container. … This type of meniscus is occasionally known as a ‘backward meniscus’, but the proper term is convex meniscus. A common liquid that forms a convex meniscus is liquid mercury. Convex menisci are read from the top of the curve at eye level.
Can a meniscus tear cause fluid on the knee?
Secondary effects. A torn meniscus often causes the knee to make extra joint fluid. There is more room in the knee for fluid when the knee is slightly bent. Therefore, people with chronic swelling tend to hold the involved knee in a bent position and develop hamstring tightness and joint contracture.
What determines the shape of a liquid’s meniscus?
When liquid water is confined in a tube, its surface (meniscus) has a concave shape because water wets the surface and creeps up the side. … When liquid mercury is confined in a tube, its surface (meniscus) has a convex shape because the cohesive forces in liquid mercury tend to draw it into a drop.
Do all liquids have a meniscus?
The meniscus of a fluid in a test tube is the result of the capillary force at the gas, liquid, solid interface (or liquid, liquid, solid). So long as the two fluids are not the same substance they will have differing properties (even if slight) and there will always be a meniscus.
What are the two types of meniscus?
The menisci — the medial meniscus and lateral meniscus – are crescent-shaped bands of thick, rubbery cartilage attached to the shinbone (tibia). They act as shock absorbers and stabilize the knee. The medial meniscus is on the inner side of the knee joint. The lateral meniscus is on the outside of the knee.
What does a flat meniscus mean?
A flat meniscus occurs when water in some types of plastic tubes; tubes made out of material that water does not stick to. In any case, you get the true volume of the liquid by reading the center of the liquid in the tube, as shown by the middle of the dashed line in the diagram.
Does a torn meniscus hurt constantly?
The pain may be sharp or instead it can just be a constant dull ache sensation. It usually hurts more when bending the knee deeply or straightening it fully. It can also hurt when twisting on the knee with your foot fixed on the ground. These locations and natures of pain may indicate meniscus damage.
Where does your knee hurt with a torn meniscus?
Symptoms of a meniscus tear may be different for each person, but some of the most common symptoms are: Pain in the knee joint: usually on the inside (medial), outside (lateral) or back of the knee. Swelling. Catching or locking of the knee joint.
What is the best exercise for a torn meniscus?
Once you have your doctor’s approval to begin exercising, try some of these exercises to enhance your strength and stability following a meniscus tear.
- Quadriceps setting. …
- Mini-squats. …
- Straight leg raise. …
- Hamstring heel digs. …
- Leg extensions. …
- Standing heel raises. …
- Clams. …
- Hamstring curls.
Do all liquids have surface tension?
The surface tension of water is about 72 mN/m at room temperature which is one of the highest surface tension for liquid. There is only one liquid having higher surface tension and that’s mercury which is a liquid metal with a surface tension of almost 500 mN/m.
What is cohesive and adhesive?
Cohesion: Water is attracted to water, and Adhesion: Water is attracted to other substances.
What determines the shape of a liquid?
In a liquid, the particles are still in close contact, so liquids have a definite volume. However, because the particles can move about each other rather freely, a liquid has no definite shape and takes a shape dictated by its container. … No definite shape (takes the shape of its container). Has definite volume.
Does alcohol form a meniscus?
This happens because alcohol and water have different surface tension. … From there, due to a gradient of the surface tension between the wall of the glass and wine surface, stable droplets or bubbles form (called « beading » in the liquor industry), and fall back to the meniscus due to gravity.
What is a meniscus graduated cylinder?
A meniscus is the curved surface at the top of a column of liquid. In a science class, this liquid is usually water or some sort of aqueous solution, and the column is usually a graduated cylinder or a pipet. As you may have noticed, when water is in such a thin glass tube, it does not have a flat surface at the top.
Where is meniscus pain felt?
Symptoms of a meniscus tear may be different for each person, but some of the most common symptoms are: Pain in the knee joint: usually on the inside (medial), outside (lateral) or back of the knee. Swelling. Catching or locking of the knee joint.
Is it worth having meniscus surgery?
What are the benefits? Surgery to repair tears in the meniscus relieves symptoms 85% of the time. That means that of 100 people who have this surgery, 85 have relief from pain and can use their knee normally, while 15 do not. Surgery to repair tears may reduce the risk of long-term joint problems.
What is a meniscus in the knee?
The meniscus is a c-shaped pad of cartilage in the knee that acts as a shock absorber. Each knee has two menisci. Meniscus tears are common knee injuries. Knee arthroscopy is often used to treat meniscal tears.
Will walking on a torn meniscus make it worse?
In serious cases, it can develop into long-term knee problems, like arthritis. In addition moving around with a torn meniscus could pull fragments of the cartilage into the joint causing larger knee issues which could requiring more significant surgery in the future.
Do I need surgery for meniscus tear?
A tear that gives you a lot of pain or impairs use of your knee may require surgery to remove or repair the torn part of the meniscus. Complex tears usually require surgery to trim the damaged part of the meniscus.
How long are you off work for a meniscus surgery?
If you sit at work, you may be able to go back in 1 to 2 weeks. But if you are on your feet at work, it may take 4 to 6 weeks. If you are very physically active in your job, it may take 3 to 6 months.
How bad is a torn meniscus?
A moderate tear can cause pain at the side or center of your knee. Swelling slowly gets worse over 2 or 3 days. This may make your knee feel stiff and limit how you can bend your knee, but walking is usually possible. You might feel a sharp pain when you twist your knee or squat.
Is it OK to ride a bike with a torn meniscus?
Riding a stationary bike may be an important component of your knee meniscus tear exercise program. Bike riding can have many benefits, including: It can improve your knee range of motion.
What should I avoid with a torn meniscus?
Prevention. The only way to prevent and avoid a torn meniscus is to avoid activities that cause the knees to twist, bend, or rotate in an extreme fashion. If a person cannot avoid these activities, they should take as much care as possible while participating in them.
Can you make a meniscus tear worse?
If you have a mild ache during the run, or a mildly sore knee after a run then you can often continue running. There is very little risk that running will worsen the tear. Meniscus tears can always worsen… remember, this is a process of degeneration.
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