Why Do They Hit Your Knee at the Doctor?

Why Do They Hit Your Knee at the Doctor? 

You’ve probably wondered: “Why do they hit your knee at the doctor?” Well, this is an exercise that activates the patellar reflex. This tendon, located below the kneecap, is part of your nervous system. When this tendon is strained, the knee jerks. You might wonder if your knee is hurting. Thankfully, we’ve outlined a few causes of the knee jerk reflex and how you can prevent it in the first place. 

(Looking for Knee Doctors in Omaha? Contact us today!)

Reflexes that protect air passageways 

Reflexes are automatic responses that we have without thinking about them. When we’re in danger or exposed to something threatening, our bodies respond automatically to protect themselves. Reflexes protect us from the harmful things we come in contact with every day, including germs and viruses. They protect us from injury by sending signals to our respiratory centers in the brain stem. Here, we’ll learn about the reflexes that protect air passageways at the doctor. 

Reflexes that protect joints 

Reflexes protect our bodies. For instance, the reflex when a hand is placed on a hot stove makes the hand immediately pull away, so that our brains will not receive a warning that the hand is hot. There are other protective reflexes, such as blinking when an object flies near our face, raising an arm when a ball is thrown toward us, and coughing to clear the air of something irritating. 

The stretch reflex is a protective mechanism that prevents tendons and muscles from tearing or straining. The impulse is sent from the muscle spindle to a motor neuron, which splits the signal to relax and contract. If both muscles were to contract simultaneously, the resulting forceful contraction would cause damage to the muscles. However, the stretch reflex inhibits the contraction of the antagonist’s muscle. This protective reflex keeps us safe from injury. 

Reflexes that protect menisci 

Your knee may be bending or straightening with the help of reflexes. These reflexes are vital for maintaining your balance. When you stand up, gravity will bend your knee. This reflex will help you remain upright by straightening it. Your doctor will check for DTRs on the elbow, and crook of your arm, wrist, and ankle. Your knee might be bent, but you may still be able to walk normally. 

Reflexes are natural reactions that happen without conscious thought. Every healthy person has them. These reflexes are your body’s built-in safety mechanisms. You’ll never know when a reflex may be helpful or harmful, and they are vital for our overall health. Moreover, they protect us from injury by protecting our joints and bones. Therefore, when you’re in pain, don’t wait any longer and visit a doctor right away. 

Reflexes that control knee jerk reflex 

At the doctor, you may be asked to demonstrate your knee-jerk reflex. Normally, you will do so when you are tapped beneath the knee. This tap activates a sensor inside the muscle. A signal then travels down the sensory neuron to the spinal cord, where it crosses a synapse and reaches a motor neuron. The result is the leg kicking out. 

The patellar tendon is another part of the leg that triggers the knee jerk reflex. The sensory nerve in the knee attaches directly to the motor neuron in the spinal cord, while an inhibitory interneuron relaxes the antagonistic hamstring muscle. During the test, the patient may try to consciously inhibit his response, which will affect the accuracy of the reflex. The physician may also use a technique called the Jendrassik maneuver to ensure that the test is more reliable.