2 DEFINITIONS DEFINITIONS: What is neuromuscular control? What is kinesthesia?What is proprioception?What is muscle stiffness?Kinesthesia: essentially, what you feel when a joint is moving. Ex: Throwing a baseball, arm behind, beside, in front, including accelerationProprioception: Where you joint is in relation to space.For both proprioception and Kinesthesia the messages are sent back to the CNS with afferent nervous fibresMuscle Stiffness: muscles ability to resist stretch and deformationThrough muscle stiffness increased stability of the joint occursNeuromuscular control: Through these three mechanisms and the afferent NS telling the CNS what is occuring, the efferent NS is able to better execute NM control
3 DEFINTIONS Neuromuscular Control Is the integration of a number of sensations from the periphery. These “inputs” from the periphery are combined with a coordinated muscular response as the outcome (the efferent response)
4 DEFINITIONS Kinesthesia It is the sensation or feeling of joint motion or acceleration. It is also the awareness one has of their body in space (knowing how quickly your hip, knee and ankle joints are moving when you walk)essentially, what you feel when a joint is movingThese sensations are transmitted to the CNS via afferent pathways.
5 DEFINITIONS Proprioception? Is both the conscious and unconscious appreciation of joint position…or the ability to determine the position of a joint in space (i.e. where your foot is when you walk, in relation to your hip, knee and ankle)These sensations are transmitted to the CNS via afferent pathways.
6 DEFINITIONS Muscle stiffness? It is the muscle’s ability to resist stretch/deformation. It is through this resistance that there is an increase in joint stability/restraint to joint displacement.
7 PHYSIOLOGY Mechanoreceptors? They are specialized nerve endings that respond to mechanical changes (deformation) of tissue. the change in the tissue causes the mechanoreceptor to “fire”.Golgi Tendons and Muscles spindles – involved in afferent stretch reflex
8 PHYSIOLOGY MECHANORECEPTORS: There are 2 types: 1. Articular Found within joints (ligament, capsule, menisci, and labrum)Function: stabilize and guide skeletal segments while providing mechanical restraints to abnormal joint movements.
9 PHYSIOLOGY MECHANORECEPTORS: 2. Tenomuscular: Include both muscle spindles, embedded within the skeletal muscle, detect length and rate of length changes (the stretch reflex) andTenomuscular
10 GTO’s responsible for monitoring muscle tension or load, located within the tendon and tenomuscular junction, force detectors (inhibit muscle activation when excessive loading might cause damage under load)
11 MECHANORECEPTORSBoth respond to changes in muscle length. GTO’s also respond to changes in muscle tension.Muscle spindles elicit a reflex contraction in the agonist muscleGTO’s cause relaxation (protection)
12 Muscles Agonist –the muscle that contracts to produce a movement Antagonist – the muscle being stretched in response to contraction of the agontist
13 PHYSIOLOGY neural pathways of peripheral afferents Either one (or both) of the mechanoreceptors respond to a signal (i.e., deformation in joint; change in muscle length/tension).Send signal along afferent nerve to the CNS (cerebral cortex, or directly synapses at spinal level…ie knee jerk of muscle spindles)CNS evaluates the signal, then responds via efferent nerve to the appropriate muscle/tendon for the required response.
14 REESTABLISHING NM CONTROL Why is NM control important in the rehab process?When injured, there is an increase in the response time of the mechanoreceptors.This leads to mechanical instability and functional instability (i.e. balance on foot)Must retrain the mechanoreceptors in order to increase the reaction time of those mechanoreceptors and decrease the chance of potential re-injury due to mechanical instability.
15 REESTABLISHING NM CONTROL Therefore we must retrain the Mechanoreceptors in order to increase the reaction time and decrease the chance of potential re injury due to mechanical instability.
16 REESTABLISHING NM CONTROL Objectives of NM RehabilitationFour key elementsProprioceptive amd Kineshetic sensationDynamic joint stabilityReactive NM controlFunctional motor patterns
17 REESTABLISHING NM CONTROL What are some techniques that can be used to “train” or improve an athlete’s neuromuscular control?
18 REESTABLISHING NM CONTROL Training NM ControlCKC activitiesBalance trainingReflex facilitation through reactive trainingStretch shortening exercises (plyos)Biofeedback trainingCKC activities are better for training the mechanoreptors. Compression within the joint causes a more stabilityBalance – ex: 747
20 REESTABLISHING NM CONTROL UPPER EXTREMITY TECHNIQUESCKC (PU’s, slide board, circles, etc)Stable to unstable platformsPlyo ball training (for stretch shortening/reactive training)Reactive NM activities (maintain hand position against resistance) light trainingFunctional training , ball tossesCkc – pushups, slide boards,
21 REESTABLISHING NM CONTROL Important point:During rehab, it is important to progress the athlete into “unstable” positions. By doing so, the athlete will “learn” what the position feels like, and how to prevent the position from happening/over-extending.i.e. in shoulder dislocation, train in increasing abduction/external rotationALWAYS start with a STABLE position thinking safety firstThen progress to various levels of instability.
22 Functional Instability Decreased NM Control LIGAMENTOUS INJURYRepetitive Injury Instability proprioceptive deficitsFunctional Instability Decreased NM Control