firstname.lastname@example.org LECTURE IVMANUAL MUSCLE TESTING DR. AMAL HM IBRAHIM PROFESSOR OF PHYSICAL THERAPY
email@example.com MANUAL MUSCLE TESTING The ward “strength” has multiple meanings within the profession of physical therapy. These multiple meaning have caused difficulty in communication, and led to opposing conclusions among clinicians concerning a patient’s functional ability.
firstname.lastname@example.org MANUAL MUSCLE TESTING Manual muscle test is one method by which muscle strength is defined and measured. History of manual muscle testing (Robert W. Lovett 1912). MMT uses the principles of gravity and applied external load to determine the ability of a patient to develop muscle tension voluntarily.
email@example.com MANUAL MUSCLE TESTING MMT must reflect the function of the neuromuscular system. MMT has been and still is considered a useful diagnostic and prognostic tool that can be used to judge the effectiveness of therapeutic programs.
firstname.lastname@example.org PRINCIPLES OF MMT The Guide to Physical Therapist Practice lists both manual muscle testing (MMT) and dynamometry as appropriate measures of muscle strength. Manual muscle testing is a procedure for the evaluation of the function and strength of individual muscles and muscle groups based on the effective performance of a movement in relation to the forces of gravity and manual resistance. Dynamometry is a method of strength testing using sophisticated strength measuring devices (e.g., hand-grip, hand-held, fixed, and isokinetic dynamometry).
email@example.com PRINCIPLES OF MMT Muscle strength is the ability of muscle to develop tension through its long axis. Muscle tension can be resolved into two forces, one acting along the long axis of the bone upon which the muscle functionally insert, and the other perpendicular to that axis. 1- Stabilizing force. 2- Rotating force.
firstname.lastname@example.org PRINCIPLES OF MMT The muscle torque must overcome the torque created by the weight of the extremity and any applied force in order to move or maintain the position of body segment.
email@example.com PRINCIPLES OF MMT For grading strength there are three factors: 1- The extent of the arc of movement. 2- The gravity. 3- The amount of force applied by examiner in a direction opposite to the torque exerted by the muscle group being tested. Some times the effect of gravity on the segment cannot obtained.
firstname.lastname@example.org PRINCIPLES OF MMTMedical Daniels and Kendall and ExplanationResearch Worthingham McCrearyCouncil5 Normal(N) 100% Holds test position against maximal resistance4+ Good + (G+) Holds test position against moderate to strong pressure4 Good(G) 80% Holds test position against moderate resistance4- Good – (G-) Holds test position against slight to moderate pressure3+ Fair + (F+) Holds test position against slight resistance3 Fair (F) 50% Holds test position against gravity3- Fair- (F-) Gradual release from test position2+ Poor + (P+) Moves through partial ROM against gravity OR Moves through complete ROM gravity eliminated and holds against pressure2 Poor(P) 20% Able to move through full ROM gravity eliminated2- Poor – (P-) Moves through partial ROM gravity eliminated
email@example.comPRINCIPLES OF MMT In the Medical Research Council scale, the grades of 0, 1, and 2 are tested in the gravity- minimized position (contraction is perpendicular to the gravitational force). All other grades are tested in the anti-gravity position. The Daniels and Worthingham grading system is considered the more functional of the three grading systems outlined in Table 1 because it tests a motion that utilizes all of the agonists and synergists involved in the motion
firstname.lastname@example.org PRINCIPLES OF MMT The Kendall and McCreary approach is designed to test a specific muscle rather than the motion, and requires both selective recruitment of a muscle by the patient and a sound knowledge of anatomy and kinesiology on the part of the clinician to determine the correct alignment of the muscle fibers. Choosing a particular grading system is based on skill level of the clinician while ensuring consistency for each patient, so that coworkers who may be re- examining the patient are using the same testing methods.
email@example.com PRINCIPLES OF MMT It must be remembered that the grades obtained with MMT are largely subjective and depend on a number of factors including the effect of gravity, the manual force used by the clinician, the patients age, the extent of the injury, and cognitive and emotional factors of both patient and clinician
firstname.lastname@example.org PRINCIPLES OF MMT Daniels and Worthingham describe P+ as the grade indicating movement of the segment through full range of motion in the gravity- diminished or in the partial range against gravity. Kendall et al consider P+ (30%) as movement of the extremity through a larger arc of motion in the gravity-diminished position than that designated by the criteria for 20 percent grade.
email@example.com PRINCIPLES OF MMT In contrast, for the same muscle group, Kendall et al, have the patient either sitting or supine, moving the supinated forearm to a test position of 90º flexion or less, or holding the test position against the applied force. Stabilization is minimal by the examiner who places one hand under the patient’s elbow.
firstname.lastname@example.org GRADING SCALE: (DANIEL & WORTHINGHAM 1995) Rating muscle tests is a skill that takes a long time to learn and perform with reliability. It is important to learn how much resistance a “normal” muscle can tolerate to know when a muscle is not performing to its potential. All tests must be performed bilaterally and the unaffected side should be tested first. This is crucial because the tester can then get an accurate idea of how much resistance the unaffected side can tolerate and what would be considered normal for the patient.
email@example.com PRINCIPLES OF MMT MMT requires attention to positioning, stabilization and the methods of applying external force to the body segment. Standardization of these factors from one patient to another is important because the examiner must develop an experiential model with which the results of each muscle group tested will be compared.
firstname.lastname@example.org PRINCIPLES OF MMT There are differences between testing methods in positioning , stabilization and the way in which manual forces are applied. Daniels and Worthingham 1980 recommended elbow flexion test from sitting with arm stabilized at the side, and if the biceps is the main concern, the forearm supinated. The arm should move through full arc of motion with the examiner applying force at the end of motion (break test).
email@example.com PRINCIPLES OF MMT In contrast for the same muscle group Kendall et al 1971, have the patient either sitting or supine, moving the supinated forearm to a test position of 90ºof elbow flexion or slightly less or holding the test position against the applied force. The examiner’s force is applied to the forearm in the test position of 90º of elbow flexion. Stabilization hand is under the patient’s elbow.
firstname.lastname@example.org PRINCIPLES OF MMT Although the two methods are different there is no evidence suggesting different results. Position (sitting and supine) can yield different strength measures. Muscle torque in example of Daniels and Worthingham, the flexors are mechanically and physiologically disadvantaged.
email@example.com PRINCIPLES OF MMT The effect of the external force in resisting muscle group torque is a function of the distance of its application from the joint axis. If the examiner changes the distance at different times with the same patient and among patients, appropriate measurement can not be obtained. The skill of examiner to apply external force is important (gradual, in correct direction and differentiating).
firstname.lastname@example.org PRINCIPLES OF MMT The muscle ability to develop tension varies according to the type of muscle contraction. Eccentric contraction generates the greatest amount of tension followed by isometric and then concentric contraction.
email@example.com PRINCIPLES OF MMT The effect of the external force in resisting muscle torque is a function of the distance of its application from the joint axis. If the examiner changes the distance at different times with same patient or among patients the muscle strength related to sex, age, body type and life style cannot obtained.
firstname.lastname@example.org RELIABILITY OF MMT Intra-rater reliability examined by two therapist performed MMT on poliomyelitis patients at 6 week interval. Intra-examiner agreement occurred on 65% and 54% of the grades. Agreement occurred within a plus or minus grade on 82% and 84% of the muscle tested, Iddings and Smith 1961,
email@example.com RELIABILITY OF MMT Iddings and Smith 1961, had 10 physical therapists complete a MMT on a poliomyelitis patients within 2 week period. A training period was not provided; each examiner performed the test by his or her customary manner. Nine of the examiner’s muscle grades were compared with the tenth. The nine physical therapist on the average agreed completely with the tenth (45.3%) and 63.8% in plus or minus grades.
firstname.lastname@example.org RELIABILITY OF MMT An inter-rater reliability study, physical therapist, nurses and physicians were instructed in standardized methods of muscle testing. They reported that the average difference between examiners was 7.1%. When two physical therapist were compared, the difference in grading was 3%, in agreement in 60% of instances and 95% within plus or minus one grade.
email@example.com VALIDITY OF MMT MMT has face validity which is defined as the extent to which the test appears to measure what it was intended to measure. Content validity reflects the adequacy of test construction (known physiologic, anatomic, and kinesiologic principles). For example, test grade fair for tibialis anterior the muscle should be able to move the foot through full arc of motion against gravity.
firstname.lastname@example.org VALIDITY OF MMT The tibialis anterior should be able to resist some degree of applied external force. MMT has some content validity because it measure directly the torque of muscle testes but not all types of contractions or the rate of tension develop during test. Agreement of knowledgeable persons that test construction is sound is an indication of a high degree of content validity of a test.
email@example.com VALIDITY OF MMT Construct validity as related to MMT, represents the degree to which one can generalize the results of the test to relevant behaviors. As in tibialis anterior example which indicates the muscle inverts and dorsiflexes the foot through full range of motion while subject is sitting over edge of table (non-weight bearing) while it is main muscle in gait (push off and heel strike).
firstname.lastname@example.org VALIDITY OF MMT Because MMT do not examine muscles during meaningful functional activity, the use may be limited for the neurological patients. MMT is hypothesized as valuable measurement tool for the clinical assessment of patients with neuromuscular problems.
email@example.com MMT OF THE PEDIATRIC PATIENT Muscle testing the pediatric patient is different from the technique used in adult practice. It is essential to have an understanding of normal growth and development. In very young child, the use of reflexes will assist in the evaluation process. In the older child, the use of developmental tasks will help to assess muscle activity.
firstname.lastname@example.org MMT OF THE PAEDIATRIC PATIENT It is better to divide the exam into three age and developmental categories: 1- infants: birth through 12 months. 2- toddler: 12 months through 24 months. 3- preschooler: 24 months through 48 months. Children over 4 years of age can be more formally tested.
email@example.com MMT OF THE PEDIATRIC PATIENT Early Reflexes Reflex Emergence Disappearance Moro birth 5 to 6 months Palmar grasp birth 3 months Plantar grasp birth 12 months Placing birth 12 months Protective: lateral 6 to 9 months PersistsProtective: parachute 9 months Persists
firstname.lastname@example.org MMT OF THE PEDIATRIC PATIENT Developmental Milestones Age Activity birth Flexion of limbs Ventral suspension, head in line with body3 months Head control midline Reaches for objects Head upright in prone6 months Sits with balance from hands Can bear weight on leg Transfers objects hand to hand9 months Sits independently Pulls to stand Crawling and cruising Pincer grasp12 months Walking alone
email@example.comMMT OF THE PEDIATRIC PATIENT Developmental Milestones Age Activity 18 months Creep up stairs Throws a ball 24 months Runs Walks up and down steps Kicks a ball 30 months Jumps 36 months Stands on one foot momentarily 48 months Hops on one foot Throws a ball overhand 60 months skips
firstname.lastname@example.org THE MUSCULOSKELETAL EXAM The infant exam:1- by observation.2- evaluation: From supine. From prone. Vertical. Horizontal. Sitting. Floor play
email@example.com THE MUSCULOSKELETAL EXAM The toddler exam:1- by observation.2- by evaluation: Sitting on the table or parent’s lap: evaluate upper limb by using toy, transfer objects to the opposite hand. Check lateral protective reflex. Floor exam: watch child from supine to sit, stand up and watch trunk and lower limbs, ask child to walk, have child kick a ball.
firstname.lastname@example.org THE MUSCULOSKELETAL EXAM The preschool exam1- observation.2- evaluation: Sitting on the exam table. Lying on the exam table. Floor exam.
email@example.com 6 MINUTE WALK TEST This test measures your response to exercise, at your own pace. Some people have no problems at all. Others may have shortness of breath, chest pains, leg pains, etc. You may stop the test at any time if you are not feeling up to it or if a problem occurs during the walk.
firstname.lastname@example.org TANDEM WALK TEST Description The TW quantifies characteristics of gait as the patient walks heel to toe from one end of the forceplate to the other. Measured parameters are step width, speed, and endpoint sway velocity.
email@example.com REACTION TIME Reaction Time (RT) is the time in seconds between the command to move and the patients first movement.
firstname.lastname@example.org STANDING BALANCE TEST the person stands on one leg for as long as possible. Give the subject a minute to practice their balancing before starting the test. The timing stops when the elevated foot touches the ground or the person hops or otherwise loses their balance position. The best of three attempts is recorded. Repeat the test on the other leg.