Muscle strength (broad) the force produced by a muscle when it contracts.
(Narrow sense) The force produced when a muscle contracts actively, i.e., the ability to contract statically or dynamically.
Muscle weakness (hypotonia) refers to a muscle or a group of muscles with a reduced or even lost ability to contract actively.
I. Classification of muscles
Prokinetic muscles initiate and maintain the primary role of a muscle or group of muscles in an action.
Antagonist muscle with the opposite role of the prime mover muscle.
The muscle or muscle group that cooperates with the prime mover and contracts together with the prime mover.
A joint muscle with the same function.
Neutralizing muscles eliminate unnecessary movements.
Fixed muscle fixes the related limb.
Second, the type of muscle contraction
Isometric contraction muscle force increases significantly, but the muscle length basically does not change, and does not produce joint movement.
Isotonic contraction muscle force is basically unchanged, but the muscle length is shortened, causing joint motion.
Centripetal contraction.
Centrifugal contraction.
Isotonic contraction movement speed.
Third, the factors affecting muscle strength
The cross-sectional area of the muscle.
The type of muscle fiber.
Degree of motor unit recruitment and frequency of nerve impulse delivery.
The initial length of the muscle.
The type of muscle contraction.
Angle of the joints.
Age and gender.
IV. Purpose of assessment
(A) The purpose of physiotherapy assessment
To determine the site and degree of muscle weakness.
Differential diagnosis of soft tissue injuries.
To assist in the localization and diagnosis of certain neuromuscular diseases.
To prevent injury and deformity caused by muscle strength imbalance.
To evaluate the effect of muscle strength enhancement training.
V. Indications and contraindications
(A) indications
1, lower motor neuron injury.
2.Primary myopathy.
3, bone and joint diseases.
(B) Contraindications
1.Local inflammation, joint cavity effusion, joint instability, acute sprain.
2.Severe local pain.
3.Severe heart disease or hypertension.
The unassisted muscle strength assessment is to have the patient do standard movements in a specific position, by touching the muscle belly, tendons, and observing the ability of the muscle to complete the movement in a weight loss state or to overcome its own gravity or against resistance, so as to assess the muscle strength level or size of the patient’s ability to actively contract the muscle.