no you should not strike the joint ,but as the name suggest we should strike the tendon
Yes, deep tendon reflexes are tested with a reflex hammer, which is used to strike a tendon directly. This action stretches the muscle attached to the tendon, leading to a reflex contraction that is then assessed for strength and speed.
The reflex hammer is used to check a person's reflex reponses. It is intended for testing tendon reflexes by striking the tendons. The reflex hammer is held by the handle, particularly close to the end oposite the head, with the head resting on the tendon which you intend to test. Make sure that the head is correctly lined up relative to the tendon. The hammer should be held against the tendon for some time such that the person being tested does not know when to expect the reflex. The hammer is now swung back and "bounced" off the tendon. It is important to make sure the hammer has a great velocity at the moment of impact (but don't use too much force to avoid hurting the tendon) and that it bounces off the tendon, rather than staying in contact with it. The action should be very brisk. It is usually completed in about a second.
The test that makes use of a special hammer is the neurological examination test known as the reflex hammer test. This test is used to assess deep tendon reflexes by tapping on specific areas on the body with the hammer.
The Femoral nerve. Wikipedia: Striking the patellar tendon with a tendon hammer just below the patella stretches the quadriceps muscles in the thigh. This stimulates stretch sensory receptors (i.e. muscle spindles) to trigger an afferent impulse in a sensory Ia-nerve fiber of the femoral nerve which synapses (without interneurones) at the level of L4 in the spinal cord, completely independent of higher centres.
The patella reflex tests the integrity of the patellar tendon and the sensory and motor pathways that control the reflex. When the patellar tendon is tapped, it should cause the quadriceps muscle to contract and the lower leg to extend. If there is a lack of response or an abnormal response, it can indicate a problem with the nervous system.
1. Have the subject remove a shoe and sock and position the knee on the seat of a chair. 2. tap the Achilles tendon sharply with a reflex hammer. 3. observe the foot for any motion- the expected response should last between 100 and 300 msec so it may be difficult to visualize.
The Jendrassik maneuver is a medical maneuver wherein the patient flexes both sets of fingers into a hook-like form and interlocks those sets of fingers together. The tendon below the patient's knee is then hit with a reflex hammer to elicit the patellar reflex. The elicited response is compared with the reflex result of the same action when the maneuver is not in use. Often a larger reflex response will be observed when the patient is occupied with the maneuver, as the maneuver may prevent the patient from consciously inhibiting or influencing his or her response to the hammer.
- Golgi tendon reflex - When there is too much tension on a muscle, the afferent sensory nerves send the information to the spinal cord which sends its information to the cerebellum where the information is used to adjust muscle tension. Simultaneously, the motor neurons of the spinal cord that innervates the contracting muscle are inhibited and the antagonistic muscles are activated. I believe (but am not certain sure) the term you're looking for is "deep tendon reflex" (aka "monosynaptic reflex"). When a muscle's tendon is suddenly stretched, receptors within the tendon send signals to cause the muscle contract, so it opposes the stretch. This is the reflex that's tested when you tap just below your knee and your foot swings out (a knee-jerk reaction :-) See Glossary of Terms in Spinal Cord Injury Research [sci.rutgers.edu/dynarticles/CareCureGlossary_20Jun02.doc ]
Yes, the automatic jerking of the knee when a doctor taps it is known as the patellar reflex or knee-jerk reflex. This involuntary response occurs when the tap stimulates sensory receptors in the tendon, sending signals to the spinal cord, which then immediately sends a signal back to the muscles to contract. It is a protective mechanism that helps maintain posture and balance. This reflex is commonly tested during physical examinations to assess the nervous system's function.
musculocutaneous nervethe musculocutaneous nerve
The Moro reflex is typically tested in infants to assess their neurological development and response to stimuli. It is one of the primitive reflexes present in newborns and fades away by around 4-6 months of age.
Typically, a reflex is tested a few times to ensure accuracy in the assessment. The number of tests can vary depending on the specific reflex being evaluated and the individual's response.