Knee extension mechanism

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Knee extension mechanism is composed by「 quadriceps」 -「 tendon of the quadriceps」 –「 kneecap」–「 patella ligament」 -「 tibial tuberosity」, and it means muscle, a tendon, and the ligament which are used when we stretch out a knee.

It seems that the athletic injure of children is mainly by overuse of the knee.
Osgood disease
It is a disease to bring a pain and swelling to the tibial tuberosity (the left figure) which is an attachment site of the patellar ligament by sports activity and so on in the childhood which growth is vigorous. It often occurs in the boys of 10 -15 years old, and the boys of 10 years old - 15 years old have many it, and it is recognized well by players such as soccer and volleyball, basketball, track and field, the baseball.


What is the tibial tuberosity
It is the projection of the bone under approximately 3cm of the kneecap (plate).


Cause

Patellar ligament is abnormally pulled by overdoing of the exercise to lengthen a knee and epiphyseal line (growth line) is damaged and has it.

The left X-ray is the epiphyseal line on the tibial tuberosity, and a bone is destroyed.
The broken bone hardens around the tibial tuberosity and swells out. A pain comes out around there.

:an injury of epiphyseal plate

Jumper knee

It is generally about the pain mainly on kneecap (plate) generated by sports activity to repeat a jump and a kick, sudden stop movement generally.
It occurs by overdoing of the exercise to lengthen a knee in the case of a jump and a kick.

Most of the jumper knee (60-70%) is the pain of lower part of the plate.
Jumper knees are recognized well in the players such as volleyball and soccer, basketball, and gymnastic exercises.A symptom is a pain around the kneecap. The pain exacerbates it on exercises and is resolved by rest.

quadriceps inflammation

There is a pain in the upper part of the patellar ligament inflammation kneecap.

脛骨粗面:tibial tuberosity

Sinding-Larsen-Johansson
There are bone fragments, abnormal ossification, and lime image in the bottom end of the kneecap

patella ligament inflammation
There is a pain in the patella ligament inflammation

Discoid meniscus damage

Childhood meniscus damage is mainly discoid meniscus damage.
The discoid meniscus which is native form abnormality occurs inward outward, but the most are the outside.

Since the discoid meniscus is bigger and thicker than a normal meniscus, it is always inserted between thighbone and tibias and is shocked and is in a fragile state. Therefore, it is damaged easily by even a minimal injury.
The symptom appeals for a catch by the expansion and contraction of the knee and accepts a sound called “the cock” and the sport disorders (the state having difficulty in completely stretching out a knee).

The meniscus of the right knee


It is between a thighbone and a lower bone; and it is the roll of the cushion

This is that we look at the normal meniscus from the top

An abnormal discoid meniscus since birth

Anterior cruciate ligament damage

The typical state of the anterior cruciate ligament damaged knee is that anterior cruciate ligament is easily damaged when we hold on, stretch out a knee, stop suddenly, and land from the high place in "the state that a knee enters inward and a tiptoe turns to the outside"

It is easy to be occurred basket, ,ski, volleyball, and soccer.
Until three weeks after the injury

・We feel the sound like “bekii, or bokii” at the time of injury

・We crouch down with a knee, but when become able to stand in a few minutes, a knee is anything, or is unstable shakily; and become unreliable at the time of injury.
・The swelling of the knee joint is seen together in progress at time after the injury.
・New fresh blood (knee joint blood symptom) is seen when a knee is injected at a hospital.
・These symptoms gradually resolve in one or two months.

The chronicity period (after three months after injury)
・Giving way: The phenomenon that a knee buckles when we walk and turn around suddenly
・Atrophy of the quadriceps: The muscle of the thigh narrows
・It causes meniscus and the cartilage damage secondarily, and swelling, sharp pain come to be caused.
・We feel like a knee coming off and cannot play sports.

In the case of anterior cruciate ligament damage, it will be the left animation without ligament.
The bone under a knee comes to come out before a knee.

There are posterior cruciate ligament damage, iliotibial band inflammation, osteochondrosis dissecans inflammation, and lower leg fatigue fracture as well.