chapter10 chapter 10 Assessing Flexibility Author name here for Edited books
Objectives • Differentiate between static and dynamic flexibility • Identify factors affecting flexibility • Identify methods for assessing flexibility • Understand reliability and validity of flexibility assessments • Understand general guidelines for flexibility testing • Understand how to assess flexibility of older adults
Basics of Flexibility • Flexibility and joint stability are highly dependent on • joint structure and • strength and number of ligaments and muscles spanning the joint.
Definitions and Nature of Flexibility • Flexibility is the ability of a joint, or series of joints, to move through a full range of motion (ROM) without injury. • Static flexibility is a measure of total ROM at the joint, limited by the extensibility of the musculotendinous unit. • Dynamic flexibility is a measure of the rate of torque or resistance developed during stretching throughout the ROM. (continued)
Definitions and Nature of Flexibility (continued) • ROM is highly specific to the joint and depends on morphological factors such as the following: • joint geometry • joint capsule • ligaments • tendons • muscles spanning the joint (continued)
Definitions and Nature of Flexibility (continued) • Relative contribution of soft tissues to total resistance encountered by the joint during movement: • Joint capsule—47% • Muscle and its fascia—41% • Tendons and ligaments—10% • Skin—2% (continued)
Definitions and Nature of Flexibility (continued) • Tension in the muscle–tendon unit affects both static (ROM) and dynamic flexibility (stiffness or resistance to movement): • viscoelastic properties • elastic deformation • viscous deformation • stress relaxation
Factors Affecting Flexibility • Hypertrophied muscles and excess subcutaneous fat may impede flexibility. • Static flexibility progressively decreases as muscle stiffness increases with aging. • Females are generally more flexible than males, regardless of age; may be joint-specific. • Lack of physical activity is a major cause of inflexibility. • Active warm-up combined with static stretching is more effective than static stretching alone.
Assessment of Flexibility • Difficult and expensive to assess dynamic flexibility • Static flexibility assessed in field and clinical settings by direct or indirect measurement of ROM
General Guidelines for Flexibility Testing • Have client perform general warm-up followed by static stretching prior to the test. • Avoid fast, jerky movements, and stretching to the point of pain. • Administer three trials of each test item. • Compare client’s best score to norms to obtain a flexibility rating for each test item. • Use the test results to identify joints and muscle groups in need of improvement.
Direct Methods of Measuring Static Flexibility • Goniometer: protractor-like device with two steel or plastic arms that measure the joint angle at the extremes of the ROM • Flexometer: consists of a weighted 360° dial and weighted pointer • Inclinometer: measures the angle between the long axis of the moving segment and the line of gravity
Goniometry • Place the center of the instrument so it coincides with the fulcrum, or axis of rotation, of the joint. • Align the arms of the goniometer with bony landmarks along the longitudinal axis of each moving body segment. • Measure the ROM as the difference between the joint angles (degrees) at the extremes of the movement. • Follow standard procedures by joint.
Table 10.2 (continued) Table 10.2
Flexometer Test Procedures • Strap the instrument to the body segment. • Lock the dial at 0° at one extreme of the ROM. • After the client executes the movement, lock the pointer at the other extreme of the ROM. • The degree of arc through which the movement takes place is read directly from the dial.
Inclinometer Test Procedures • Easier to use than the flexometer and universal goniometer • Held by hand on the moving body segment during the measurement • Alignment with specific bony landmarks not required • American Medical Association recommends the double-inclinometer technique to measure spinal mobility.
Validity and Reliability of Direct Measures • Highly dependent on the joint being measured and technician skill • High agreement between ROM measured by radiographs and universal goniometers for the hip and knee joints • No difference between radiography and the double-inclinometer technique for assessing spinal ROM of patients with low back pain • Inclinometer reliably measures ROM at most joints (continued)
Validity and Reliability of Direct Measures (continued) • Intra- and intertester reliability of goniometric measurements affected by identification of axis of rotation and palpating bony landmarks • For inclinometer: • Intertester reliability is variable and joint specific. • Intrarater reliabilities of flexibility during hip adduction and for ROM measurements of the lumbar spine and lordosis generally exceed 0.90. (continued)
Validity and Reliability of Direct Measures (continued) • Modified sit-and-reach test to evaluate the static flexibility of the lower back and hamstring muscles: • Moderately related to criterion measures of hamstring flexibility for adults and poorly related to low back flexibility of adults • No better than that of the standard sit-and-reach test for assessing flexibility of the low back and hamstring muscle groups (continued)
Validity and Reliability of Direct Measures (continued) • Back-saver sit-and-reach test to evaluate the static flexibility of the lower back and hamstring muscles: • Validity of this test is similar to that of the standard sit-and-reach test for assessing hamstring flexibility of men and women.
Indirect Methods of Measuring Static Flexibility • Sit-and-reach test to evaluate the static flexibility of the lower back and hamstring muscles • provides an indirect, linear measurement of the ROM. • is moderately related to hamstring flexibility, but poorly related to low back flexibility. • has poor criterion-related validity and is unrelated to self-reported low back pain.
Standard Sit-and-Reach Test • Client sits on the floor with knees extended and the soles of feet against the box edge. • Client keeps knees fully extended, arms evenly stretched, and hands parallel with the palms down (fingertips may overlap). • Client slowly reaches forward as far as possible along the top of the box and holds this position for two seconds. • Client’s score is the most distant point along the top of the box that the fingertips contact.
Tips for Standard Sit-and-Reach Test • Have client warm up prior to test. • Advise your client that lowering the head and exhaling during the stretch maximizes the distance reached. • If the client’s knees are flexed, motion is jerky or bouncing, or fingertips do not maintain contact with the slider, do not count that score. • Administer two trials and record the maximum score to the nearest 0.5 cm. • Use box with zero point at 26 cm. • Interpret using gender-specific results.
V Sit-and-Reach Test • Secure a yardstick to the floor by placing tape (12 in. long) at a right angle to the 15-inch mark on the yardstick. • Client sits on floor, straddling the yardstick with knees extended, heels of feet on 15-inch mark and 1 foot apart. • Client reaches forward slowly, as far as possible, along the yardstick while keeping the hands parallel. • Client holds position about two seconds. • The score (in centimeters or inches) is the farthest point on the yardstick contacted by the fingertips.
Tips for V Sit-and-Reach Test • Don’t have client lock knees in extended position at start. • Make certain that the knees do not flex and that the client avoids leading with one hand. • Interpret the score using gender-specific normative values.
Modified Sit-and-Reach Test • Client sits on the floor with buttocks, shoulders, and head in contact with the wall. • Client extends the knees and places the soles of the feet against the sides of box. • Place a yardstick on top of the box with the zero end toward the client. • Client reaches forward with one hand on top of the other while keeping the head and shoulders in contact with the wall. (continued)
Modified Sit-and-Reach Test (continued) • Yardstick is positioned so that it touches the fingertips; this establishes the zero point for each client. • As you firmly hold the yardstick in place, client reaches forward slowly, sliding the fingers along the top of the yardstick. • The score (in inches) is the most distant point on the yardstick contacted by the fingertips.
Tips for Modified Sit-and-Reach Test • Use this test for those with long arms and short legs. • Don’t have client lock knees in extended position at start. • Make certain that the knees do not flex and that the client avoids leading with one hand. • Have client hold stretch for two seconds. • Record the higher of two measures. • Avoid fast, jerky movements. • Interpret the score using gender-specific norms.
Back-Saver Sit-and-Reach Test • Client places the sole of the foot of the extended (tested) leg against the edge of the sit-and-reach box. • Client places the foot of the untested leg flat on the floor 2 to 3 inches to the side of the extended (tested) knee. • Remainder of instructions are the same as for the standard sit-and-reach test. • Determine client’s flexibility score for each leg.
Modified Back-Saver Sit-and-Reach Test • Client performs a single-leg sit-and-reach on a 12-inch bench. • Client places the untested leg on the floor with the knee flexed at a 90° angle. • Align the sole of the foot of the tested leg with the 50-cm mark on the meter rule. • Follow instructions for the standard sit-and-reach test to determine your client’s hamstring flexibility for each leg.
Tips for Modified Back-Saver Sit-and-Reach Test • Have client warm up prior to test. • Be sure zero point of meter stick or tape measure is pointing toward client. • Secure the meter stick or tape measure to the table. • Advise your client that lowering the head and exhaling during the stretch maximizes the distance reached. • If the client’s test-leg knee is flexed, motion is jerky or bouncing, or fingertips do not remain aligned, do not count that score. • Administer two trials and record the maximum score to the nearest 0.5 cm.
Skin Distraction Test • Place a 0 cm mark on the midline of the lumbar spine at the intersection of a horizontal line connecting the left and right posterior superior iliac spines while the client stands erect. • Place a second mark 15 cm superior to the 0 cm mark. • Instruct the client to bend forward at the waist as far as possible. • Measure the new distance (cm) between the two marks. • Record the score as new distance minus 15 cm.
Lumbar Stability Tests • Use these 3 tests to evaluate the balance in the isometric endurance capabilities of back muscles in healthy individuals: • Trunk extension • Trunk flexion • Side bridge
Trunk Extension • Client lies prone with the lower body secured to the test bed at 3 places and with the upper body extended over the edge of the bed (bed is 10 inches from floor). • Client holds arms across chest, hands resting on opposite shoulders. • Client assumes and maintains horizontal position above the floor for as long as possible. • Record time (in seconds) client maintains the horizontal position; trial ends when upper body contacts the floor.
Trunk Flexors • Client sits on a test bench with a moveable back support set at a 60° angle. • Client flexes the knees and hips to 90° and folds the arms across the chest. • Use toe straps to secure client’s feet to the test bench. • Record time (in seconds) client maintains this body position after you lower or remove the back support. • Stop stopwatch when client’s trunk falls below the 60° angle.