The Chemistry of the Patella

The patella is the small triangular shaped bone on the front of the knee joint. It is the largest sesamoid bone in the human body as it is imbedded in the patellar tendon. It is positioned in a groove between the femur and the tibia (the thigh bone and the shin bone). Its position at the front of the knee joint is significant in allowing the patella to protect and color the anterior articular, or inside of the knee joint. The patellar tendon helps to secure the patella in place.

I chose to do my project on the patella because, when I was going into eighth grade I dislocated my patella. Due to my surgery and recovery, my life was centered around my knee for months which caused my curiosity of this little bone to grow. The knee joint is needed to perform the everyday task of walking. The patella protects the knee joint when it bends and straightens, a motion that happens repeatedly in everyday life.

Composition of ...

• Bone
  • Ca10(PO4)(OH)2
• Tendon
  • made of collagen fibers, and bits of copper, manganese, and calcium
  • collagen fibers made of amino acids

Main Chemicals, Compounds, Components

Bone

• How- The patella is naturally occurring and is fully developed through endochondral ossification.
• What- The patella a is the largest sesamoid bone that protects the inside of the knee. The chemical composition of bone is (Ca10(PO4)6(OH)2).
• When- As a baby the patella is made of cartilage, and it does not begin to ossify into bone until about age three.
• Why- The patella is needed to improve the function of knee and to keep inside of the knee healthy.
• Where- The patella rests in a groove below femur and above tibia.

Tendon

• How- The patellar tendon is naturally occurring in the human body.
• What- Tendons are dense, white, fibrous bands that connect a muscle to a bone. Tendons are used to help move bones and add stability. They are primarily made up of collagen, but 0.2% of tendons are made up of copper, manganese, and calcium.
• When- Tendons develop and grow with the rest of the human body.
• Why- The quadriceps tendon and the patellar tendon help to stabilize the patella, and to only allow the patella to move side to side not up and down.
• Where- The quadriceps tendon connects the patella to the quad, and the patellar tendon connects the patella to the tibia.

Chemistry's Role

Without chemistry, the bone that makes up the patella would never be made because endochondral ossification would never occur. If the cartilage that the patella starts out as never ossified, the knee joint would not be protected and covered as well or at all. Without that coverage and protection, severe injuries to the knee would occur more often. In addition, if the tendons needed to secure the patella were not produced, the patella would dislocate easily causing severe knee pain and swelling.

Background Research

• patella is largest sesamoid bone in the human body (imbedded in a tendon)
• protects and covers anterior articular (inside) of the knee joint
• contain in the tendon of the quad muscle
• free to move up and down not side to side
• sits in groove under the femur contained by walls of groove
• collagen- protein woven into a flexible framework
• contains calcium phosphate and calcium carbonate
• minerals make up the hard framework
• calcium collagen combination gives bones strength/ability to withstand stress
• calcium makes bones strong
• bones store calcium more than 99% of body’s calcium in bones (1% in blood)
• living, growing tissue
• tissue that attaches to muscle on one end and bone on the other
• made of dense fibrous connective tissue that are mostly made up of collagenous fibres

Resources

https://en.wikipedia.org/wiki/Patella

patella is largest sesamoid bone in the human body (imbedded in a tendon)

protects and covers anterior articular (inside) of the knee joint

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3435920/

there is cartilage in the knee

http://www.kneeguru.co.uk/KNEEnotes/node/1799

contain in the tendon of the quad muscle

free to move up and down not side to side

sits in groove under the femur contained by walls of groove

http://www.emedicinehealth.com/what_is_bone_loss/page2_em.htm

collagen- protein woven into a flexible framework

contains calcium phosphate and calcium carbonate

minerals make up the hard framework

calcium collagen combination gives bones strength/ability to withstand stress

calcium makes bones strong

bones store calcium more than 99% of body’s calcium in bones (1% in blood)

living, growing tissue

resorption- old bone breaks down, new bone added to skeleton

http://www.britannica.com/science/tendon

tissue that attaches to muscle on one end and bone on the other

made of dense fibrous connective tissue that are mostly made up of collagenous fibres

http://www.britannica.com/science/collagen

protein

rich in amino acid and glycine

portion of hydroxyproline

changes to gelatin if placed in boiling water

http://www.stoneclinic.com/patelladislocation

patellofemoral groove (trochlea)- V-shaped groove patella sits in under the femur

ligament holding patella tears or stretches severely when dislocated

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