Patella, also known as kneecap is a small bone located at knee joint which cover the joint where thigh bone (femur) and shinbone (tibia) both meet. The name knee cap came as it acts as a cover to the knee joint where both the thigh and shin bones joins. It is in circular-triangular shape. It is called as a sesamoid bone because unlike other bones it grows with age. It plays vital role in knee functioning. Most of the leg movements includes knee cap functioning. It makes one’s quadriceps muscles more effective.
Kneecaps in baby
As it is said that the kneecaps grows with age, the question “Are babies born with kneecaps?” raises. As an answer to this question, let’s have a look at the bone structures of a baby. Generally, an adult contains 206 bones but babies start with skeletal mix of 300 different bones and cartilage elements. As the baby grows, these 300 bones and cartilage elements fuse together and form the final 206 bones. Some of the bones in babies are made of cartilage entirely and some partially. Cartilage is soft and flexible and has the property of growing. As the baby grows the cartilage also grows and gets replaced by a bone. This is possible with the help of calcium. This is the reason why doctors say that calcium consumption is very important for babies. Among such cartilage bones, kneecaps are also one. As the babies grow old the cartilage form of patella grows stronger and forms into hard bone. This conversion of cartilage to hard bone starts at about age of 3 to 5 years.
Many people ask “Do baby have kneecaps”? Yes even if it is in the form of cartilage still it is called as patella. So, babies do have kneecaps. In human body, it is the large sesamoid bone. It has three borders, two faces, anterior and posterior and an apex. Apex is the most interior part of the bone. It faces downwards providing attachment to the patella ligament. The shin bone and thigh bone joins at the base of the patella. Vastus intermedius muscle is attached to the base and vastus lateralis and vastus medialis are attached to outer lateral and medial borders of patella respectively. When patella is in cartilage form and starts developing, an ossification centre is developed in the starting stage. The patella originates from two centres of ossification which further unites into one when the growth process of patella gets complete.
The primary function of kneecaps is to support knee extensions. It acts as an anatomic pulley for the quadriceps muscles. It helps to increase the strength of quadriceps muscles up to 50%. Interposed between the quadriceps tendon and the femoral condyles it acts as a “spacer” and protects the tendon by reducing the friction and compressive stress and minimizes the concentration of stress by transmitting forces evenly to the underlying bone.
Patellar dislocations are common among people who are physical extra active and involve in lot of physical and sport activities and also in athletes. In general, patella slides out from its original position, most commonly laterally and may cause extreme pain and swelling.