Corrective Exercises: Purposes and Special Considerations

Chapter Seven


Corrective Exercises: Purposes and Special Considerations




Introduction


The value of exercise is so commonly recognized that individuals from professions ranging from health and education to acting promote and teach exercises. In many cases the only qualification of the instructor or promoter is that of celebrity status or salesmanship skill. Unfortunately, because exercises are promoted and taught by such a wide range of individuals and are so highly publicized, there is little appreciation for the complexity of (1) how specific exercises can affect different body segments, (2) how to select exercises that complement one another, (3) how to select specific exercises for the needs of different individuals, and (4) how to instruct individuals in correct performance of their exercises. The prevailing notion is that exercises are generic, or that “one size fits all.” It is true that everyone needs exercise, but not all exercises can be recommended for all individuals, and not all individuals will perform a specific exercise in the same way.


Exercises can address three major aspects of health:



Control exercises provide the means of preventing and remediating musculoskeletal pain problems, which the individual must do to maintain a strengthening and endurance program of exercise that does not lead to problems. Strengthening cannot suffice for the control exercises. If it could, then athletes and those who perform weight-training exercises would not be injured; however, they are among those who are the most frequently injured. Control exercises must be selected for a specific individual based on a physical examination. The exercises must be taught very carefully, including monitoring the patient’s performance and assessing whether the desired outcome is being achieved. Although many exercise manuals are available, they lack the detailed discussion of the purposes of the exercises that are described, how they are to be used, and what special considerations are necessary depending upon the patient’s condition. Exercise programs do not have to be complex, but they must fit the patient’s needs and they must be performed correctly. Most often the simplest exercises are the most effective, but they can only be effective if all of the exercises are consistent in addressing the problem and if they have been well taught to the patient. Patient compliance with an exercise program is determined by whether the patient understands specifically how the exercise benefits his problem, experiences improvement in his or her condition, can easily learn how to perform the exercises correctly, and can perform the program within reasonable time constraints.


The following information describes the multiple purposes of what may seem like simple exercises. Many of these simple exercises are components of basic movements used in daily activities and will only be effective if the correct performance of the patient’s most frequently performed daily activities is also addressed in the treatment program. If good control of the trunk and pelvis is maintained, correction of daily movement patterns and postures that do not compromise this control are the keys to preventing and correcting musculoskeletal pain problems.



Standing Exercises



Forward Bending (Hip Flexion With Flat Lumbar Spine)




Correct Performance





Return to erect standing from forward bending.: This movement is primarily a hip extension movement because the spine is straight and the alignment of the trunk does not change. The patient returns to the erect position by initiating the movement with hip extension. Frequently seen performance errors include the following:




Special Considerations




Men.: It is important to distinguish between limitation in hip flexion that is secondary to hamstring shortness or because of impaired motor control of hip flexion. For many men it is a matter of muscle control, rather than short hamstrings, that limits their hip flexion range during forward bending. If the load of the upper body is large because of a long trunk or broad muscular shoulders, the activity of the hamstrings may be greater than necessary. To assess the presence of a control problem, have the patient place his hands on a table or counter top and use his arms to support his upper body and then bend forward as described in the Level 1 exercise. Very often, with the body weight of the torso supported on his hands, the patient will be able to flex his hips at least 80 degrees while his knees remain extended. This supports the belief that the limiting factor is control of the trunk and pelvis by the hip extensor muscles, not the length of the hamstrings. When the limiting factor is one of muscle control, hamstring-stretching exercises will not improve the performance of forward bending.


Teaching the patient to simultaneously flex his knees and hips during forward bending is the most effective way to increase hip flexion range and prevent the faulty hamstring strategy. Most men should be instructed in simultaneous hip and knee flexion during forward bending. This does not imply that heavy lifting should be performed in this manner, but it should be used for any activity that requires leaning over (e.g., working in the sink, picking up an object from the seat of a chair, or looking into the refrigerator).



Curled Forward Bending (Spinal and Hip Flexion)





Lateral Spinal Flexion—Side-Bending Position




Correct Performance


The patient places the hands at the lowest level of the rib cage but above the iliac crest and slowly bends to one side, primarily by tilting the shoulders rather than moving at the waist. The therapist assesses whether this method alleviates the patient’s symptoms and improves the pattern of performance by changing the motion to the thoracolumbar area rather than the lumbosacral area. The therapist also notes the quality of motion through the spinal segments. Very often in patients with back pain, the motion is a translation motion at one or two segments rather than side flexion involving all of the lumbar segments. The hand support acts as a mechanical block that limits motion at the most flexible segment and forces other less flexible segments to move.


The patient should be taught to laterally flex, primarily in the middle of the thoracic spine. Observation indicates that impairments in this motion are another reason why patients develop pain when sitting. Usually people lean sideways in their chairs or change positions by leaning from one side to the other, creating the impaired translation motion that has been described. This exercise can be done with the back against the wall to avoid any rotation or extension. If the emphasis is to be directed toward stretching the abdominal and latissimus dorsi muscles, then the patient should place the arms above the head while bending to the side. The motion should be pain free.



Single-Leg Standing (Unilateral Hip and Knee Flexion)





Special Considerations Regarding Compensatory Motions



Pelvic rotation.: In patients with back pain, when the lower lumbar spine has become the site of excessive rotation, compensatory motion can be seen in the spine. For example, during right hip flexion, the pelvis rotates to the right while the lumbar spine rotates to the left. This motion should not occur. The pelvis and trunk should maintain a constant position in the frontal plane during motions of the extremities.


To correct this error the patient contracts the abdominal muscles to prevent trunk rotation. If the movement of the pelvis is into anterior tilt on the side of hip flexion, then the patient can contract the gluteal and abdominal muscles. If the pelvis moves in a posterior tilt on the side of the hip that is flexing, then the patient should not contract his gluteal muscles because it will result in lateral rotation. The problem is most likely the stiffness of the hip extensors on the side of hip flexion.



Hip adduction.: During single-leg stance, the hip of the stance leg adducts because of weakness of the hip abductors. The pelvic tilt associated with hip adduction can result in lateral lumbar flexion, another indicator that the lumbar spine is the site of compensatory motion.


Another compensation for weakness of the hip abductors is lateral trunk flexion to the side of the stance leg. This type of compensation is considered an indicator of more severe weakness than that associated with a lateral pelvic tilt (hip adduction). To correct this movement fault, the patient tightens the gluteal muscles to prevent the pelvis from tilting laterally (hip adduction) and to prevent the associated lateral trunk flexion. In men, because of their broad shoulders, the lateral trunk flexion can be very subtle but must be carefully observed because constant repetition of this side bending will lead to hip abductor weakness.



Excessive hip medial rotation.: When excessive medial rotation of the femur occurs on the stance leg, the patient tightens the gluteal muscles to improve the control of the hip lateral rotators. The excessive hip medial rotation should be corrected because it will result in compensatory motion at the knee joint (between femur and tibia) or at the ankle and foot (pronated foot). In individuals with an immobile subtalar or mid foot, the compensatory rotation may occur between the tibia and talus rather than at the subtalar joint.








Limited Range of Hip and Knee Flexion With Trunk Erect (Small Squat)


This exercise is used relatively infrequently because of the stress on the patellofemoral joint. The number of repetitions should be kept to a minimum.





Special Considerations



Hip medial rotation, pronated foot, and hallux valgus.: Excessive hip medial rotation is often a contributing factor to development of a pronated foot and hallux valgum as described in the prior exercise. This exercise must be used carefully because of the stress it places on the patellofemoral joint. The stress arises because the femur is directed forward of the tibia and into the patella. An alternative is to practice the movement from sitting to standing, preventing hip medial rotation. This is done by emphasizing lateral hip rotation by contracting the gluteal muscles and the hip lateral rotators. This activity is better than the squat because the femur is perpendicular to the tibia at initiation, and as the knee extends, it rolls on the tibia and is not associated with as much anterior shear force.



Supine Exercises



Hip Flexor Stretch (Hip and Knee Extension With Maximal Flexion of Contralateral Hip and Knee)






Control of Pelvis With Lower-Extremity Motion (Hip and Knee Extension From Hip and Knee Flexion)




Correct Performance




• The patient begins with the hips and knees flexed (hook lying).


• The patient slides one lower extremity into extension while contracting the abdominal muscles to hold the pelvis in a slight posterior tilt and the spine in the flat to neutral position, depending upon the patient’s alignment impairment.


• The patient lowers the other leg, setting the foot on the supporting surface and trying to minimize the participation of the iliopsoas.


• The patient extends the leg by sliding the foot along the supporting surface.


• The contraction of the abdominals should not cause the sternum to become depressed or the abdomen to become distended. For maximum participation of the external obliques, the abdomen should remain concave and the therapist and patient should be able to palpate the increased tension in the muscle (on the lateral side of the abdomen, beneath the rib cage and just medial to the anterior iliac spine).


• The patient returns to the starting position by sliding one leg at a time back into the flexed position.



Gluteus Maximus Stretch (Hip and Knee Flexion From Hip and Knee Extension)






Gluteus Maximus Stretch (Hip and Knee Flexion From Hip and Knee Extension)





Special Considerations




• If there is rotation of the pelvis (the anterior superior iliac spine [ASIS] moves more than ½ inch), the patient stabilizes the pelvis with the abdominal muscles to stop rotation. This exercise is designed to use the abdominal muscles to control rotation with the external oblique muscle contracting on one side and the internal oblique contracting on the other side.


• If the patient has symptoms when performing the hip and knee flexion that are alleviated if the pelvis is stabilized, then he or she may need to decrease the load on the hip flexor muscles by sliding the foot along the table rather than lifting and holding it above the supporting surface. This exercise can be progressed in difficulty when the patient can perform it without symptoms or without spinal or pelvic motions. The following progression is suggested:




Hip and Knee Flexion, Sliding Heel From Hip and Knee Extension (Heel Slides)






Lower Abdominal Muscle Exercise Progression


This exercise is often indicated for patients with low back pain because it is designed to improve the performance of the external oblique muscles, which are important for control of posterior pelvic tilt and combined with the contralateral internal oblique, control of pelvic rotation. These muscles help to prevent the accessory or compensatory motions of the pelvis and spine that occur during movements of the lower extremity. The way the exercise is performed also helps to improve the performance of the transversus abdominis muscle that stabilizes the lumbar spine. An important consideration is that this exercise also necessitates participation of the hip flexors. Because contraction of the iliopsoas, in particular, creates compressive and anterior shear forces on the lumbar spine, the exercise must be carefully taught and performed and used with caution. Clinical observation has shown that more women than men have weak lower abdominal muscles. The proportionally larger pelvis and lower extremities of women as compared with men contributes to this situation. Pregnancy also contributes to weakness of the abdominal muscles when this is not addressed with postpartum exercises. This exercise should not be used if the patient has acute low back pain; easier forms of lower abdominal muscle exercise, such as heel slides, should be initiated. The patient should not have symptoms while performing the exercise.




Correct Performance


This is a series of nine exercises of progressively increasing difficulty. The patient starts in a position of hip and knee flexion (hook lying). The patient contracts his or her abdominal muscles by pulling his or her navel toward the spine and then performs the motions described in each level. The patient must maintain the contraction of the abdominal muscles avoiding distention of the abdomen and keeping the back flat.



1. Level 0.3 (E1)—Lift one foot with the other foot on the floor.


2. Level 0.4 (E2)—Hold one knee to the chest, and lift the other foot.


3. Level 0.5—Lightly hold one knee toward the chest, and lift the other foot.


4. Level 1A—Flex the hip to greater than 90 degrees, and lift the other foot.


5. Level 1B—Flex the hip to 90 degrees, and lift the other foot.


6. Level 2—Flex one hip to 90 degrees, and lift and slide the other foot to extend the hip and knee.


7. Level 3—Flex one hip to 90 degrees, lift the foot, and extend the leg without touching the supporting surface.


8. Level 4—Slide both feet along the supporting surface into extension, and return to flexion.


9. Level 5—Lift both feet off the supporting surface, flex the hips to 90 degrees, extend the knees, and lower both lower extremities to the supporting surface.


Once the patient can correctly perform 10 repetitions at the easiest level, he or she progresses to the next level and stops performing the previous exercise. Each exercise starts in the supine position, lying on a table or floor mat with the hips and knees flexed and the feet on the floor. The patient should be able to move the leg without moving (arching) the back. The back should be held flat (no curve) against the floor during extremity motion. If unable to keep the back flat, the patient should hold it in a constant position, without motion, during the exercise. The patient should breathe normally during the exercise. He or she should exhale when moving the second leg. The patient should place the fingertips on each side of the abdomen, just above the pelvis and below the rib cage, to monitor the contraction of the external oblique muscles. The abdomen should stay flat and not distend.



Level 0.3 (E1):



• Lying in the position indicated, the patient contracts the abdominal muscles, flattening the abdomen and reducing the arch in the lumbar spine. To achieve this the patient is instructed to “pull the navel in toward the spine.”


• The patient flexes one hip while keeping the knee flexed. By having the hip flexed more than 90 degrees, the weight of the thigh is assisting the posterior pelvic tilt and maintaining a flat lumbar spine.


• The patient returns the lower extremity to the starting position and repeats the exercise with the other lower extremity.


• The patient is cautioned not to push the nonmoving foot into the supporting surface because this will substitute hip extension for abdominal muscle action. The back must remain flat, and there should not be symptoms during performance of the exercise. Some patients may be barely able to lift the foot before having to immediately return it to the starting position.



Level 0.4 (E2):



• Lying in the position indicated, the patient contracts the abdominal muscles, flattening the abdomen and reducing the arch in the lumbar spine. To achieve this, the patient is instructed to “pull the navel in toward the spine.”


• The patient flexes one hip and uses the hands to hold the knee to the chest. While maintaining the contraction of the abdominal muscles, he or she flexes the other hip (lifts the foot off the supporting surface). The patient holds for a count of three and then returns the leg to the starting position and rests. He or she performs the exercise with the other lower extremity.


• The patient repeats the exercise five to six times if the back remains flat and he or she remains symptom free.


• If the patient is able to use just one hand to hold the knee to the chest, he or she should use the other hand to palpate the abdominal muscles.


• Some patients may be able to perform this level correctly and not level 0.3. If this is the case, they should start with this series.



Level 0.5:



He or she performs the exercise with the other lower extremity.





Level 1A:



• Lying in the position indicated, the patient contracts the abdominal muscles, flattening the abdomen and reducing the arch in the lumbar spine. To achieve this the patient is instructed to “pull the navel in toward the spine.” Contraction of the abdominals should be maintained while moving the lower extremity. If the patient is slow in performing the exercise, he or she should relax the abdominal muscles after lifting the first leg and then contract them again before lifting the second leg.


• The patient flexes one hip to greater than 90 degrees by lifting the foot from the table. By having the hip flexed more than 90 degrees, the weight of the thigh is assisting the posterior pelvic tilt and maintaining a flat lumbar spine. Optimally, the flexed extremity will maintain this position with minimal contraction of the hip flexor muscles. At this point the patient contracts the abdominal muscles and flexes the other hip by lifting the foot off the table.


• If the patient’s back begins to arch while lifting the second leg, he or she lowers the leg, relaxes, and tries again. The patient maintains the contraction of the abdominal muscles and constant position of the spine while lowering the legs, one at a time, to the starting position.


• The exercise is repeated by starting the sequence with the opposite leg.



Level 1A:



• Starting from the position indicated above, the patient contracts the abdominal muscles and holds the spine constant while flexing one hip to 90 degrees (vertical position of the thigh with the foot lifted from the table).


• The patient contracts the abdominal muscles and lifts the other leg to the same position. While maintaining the contraction of the abdominal muscles, the patient lowers the legs one at a time to the starting position.


• If the patient performs the exercise slowly, he or she may need to relax the abdominal muscles before lowering the legs and then contract them again to lower them.


• The exercise is repeated by starting the sequence with the opposite leg. The patient repeats the exercise, alternating legs, until he or she can perform it correctly 10 times. The patient can then progress to Level 1B.



Level 1B:



• Starting from the position indicated in Level 1, the patient contracts the abdominal muscles and flexes the hip to 90 degrees, lifting the foot from the table.


• While maintaining the contraction of the abdominal muscles and a constant back position, the patient lifts the other leg up to the same position. Maintaining one leg at 90 degrees, the patient places the other heel on the table and slowly slides the heel along the table until the hip and knee are extended.


• The leg is then returned to the starting position by sliding the heel along the table. The patient continues to hold the abdomen flat and back in a constant position while repeating the extension motion with the other leg and returning it to the starting position.


• The patient repeats the exercise, alternating legs, until he or she can perform it correctly 10 times. The patient can then progress to Level 2.



Level 2:



• Starting from the supine position of hip and knee flexion described in Level 1, the patient contracts the abdominal muscles and maintains a constant back position. The patient flexes the hip to 90 degrees, lifting the foot from the table.


• While maintaining the contraction of the abdominal muscles and a constant back position, the patient lifts the other leg up to the same position. Maintaining one hip at 90 degrees, the patient extends the hip and knee while holding the foot off the table until the hip and knee are resting in an extended position on the table.


• The patient returns the leg to the hip and knee flexed position. While maintaining the contraction of the abdominal muscles and a constant back position, the patient extends and lowers the other leg and then returns it to the 90-degree position. The exercise is repeated, alternating legs.


Most patients have adequate strength and control of their abdominal muscles if they can complete this level successfully. Progression to a higher level is not necessary for remediation of a pain problem. Further increases in the level of difficulty of these exercises should be primarily for improved levels of fitness. If indicated, this exercise is repeated until the patient can perform it correctly 10 times, and then he or she progresses to Level 3.





Special Considerations




• In the presence of an increased lumbar curve or excessive lumbar flexibility into extension (extension DSM), the emphasis of the program is maintaining a flat lumbar spine while performing the exercises. These exercises are not recommended when the patient has symptoms when lying supine with the hips and knees in extension. The exercise sequence for these patients should begin with the heel slide exercise.


• In the presence of a flat back but with poor control by the abdominal muscles, the lumbar spine should remain still, but flattening of the lumbar spine should not be emphasized. This exercise is particularly indicated for patients with a swayback posture in which the external obliques and the iliopsoas are long.


• Patients can test 100% for upper and lower abdominal muscle strength and still have poor control of pelvic rotation during unilateral lower extremity motion.


• Often patients who have strong rectus abdominis muscles have weak external obliques. This is believed to be because the rectus abdominis has been the primary muscle producing posterior pelvic tilt and its performance becomes more optimal than that of the external obliques. Because the rectus abdominis muscle cannot control rotation as it runs parallel to the axis of rotation, improving the performance of the external obliques is important because they participate with the internal oblique muscles for the control of pelvic rotation.


• Women should be advised not to push their head into the supporting surface. This type of inappropriate stabilization can occur in women who have very weak abdominal muscles or who have a small upper body and a large lower body.



Trunk-Curl Sit-Up (Upper Abdominal Progression)




Commentary


This exercise is seldom prescribed for patients with low back pain. The main indication for this exercise is for physical fitness. The primary muscle groups participating in this exercise are the internal obliques and rectus abdominis for the trunk-curl, with the addition of the hip flexors for the sit-up phase and the external oblique muscles for posterior pelvic tilt. This exercise is more difficult for men than for women because of the higher center of gravity in men than women. This is such a popular exercise many people have been using it as part of their fitness program without the proper individual examination and guidance for correct performance.


Physical therapists should be very familiar with all of the considerations of correct performance of this exercise to address frequently encountered errors. One of the important considerations is the degree of spinal flexibility of the patient. If the patient has excessive spinal flexibility, he or she will be able to flex the spine through a large range of motion before the initiation of the hip flexion phase. If the patient’s spinal flexibility is limited, he or she will only be able to flex through a limited range of motion before the initiation of hip flexion. As the patient’s program is progressed in difficulty, the therapist must be sure that the patient flexes to the same point in the range before progressing to more advanced exercises.


There are two main factors that can make this exercise unsafe. One factor is the anterior shear stress exerted on the lumbar spine produced by contraction of the hip flexor muscles, particularly the iliopsoas. That is why the abdominal muscles must have enough strength to maintain flexion of the spine at the time of the hip flexor contraction. If the patient’s trunk extends as the hip flexion phase is initiated, he or she should perform an easier level of the exercise to protect the spine. The other factor is excessive lumbar flexion at the end of the sit-up phase. When the exercise is performed with the hips and knees flexed, the axis of rotation is shifted from the hip joints to the lumbar spine. The patient also must contract the hip extensors more strongly when the hips and knees are flexed than when they are extended. The hip extensor contraction is to prevent the feet from coming off the supporting surface when the hip flexors are contracting to flex the trunk. This is consistent with the shorter lever arm created by hip and knee flexion and the decrease in passive stabilization of the distal attachments of the hip flexor muscles. At the end of the sit-up phase, the hips are in approximately 100 to 120 degrees of flexion depending on the degree of hip flexion that the patient assumes for the starting position. If the sit-up is performed with the hips and knees extended, the hips only have to flex to 80 degrees at the end of the sit-up motion.


The safest but not the best way to perform this exercise is to limit the movement to a trunk-curl and have the hips and knees flexed. This does not place maximum demands on the internal obliques because those demands are made when the hip flexors contract, producing anterior pelvic tilt while the trunk is flexing. At this point, the upper abdominal muscles experience the greatest demands to maintain flexion of the spine and posterior pelvic tilt.



Correct Performance


This exercise is a progression of four levels:



With a careful analysis by a physical therapist, the following method is preferred:




Level 1A:




Level 1B:



• The patient flexes the shoulders to 45 degrees with the elbows extended, as if to reach toward the feet.


• The patient lifts his or her head by bringing the chin toward the neck and slowly curling the trunk (flexing the spine). The correct movement of the head is to reverse the cervical curve by bringing the chin toward the neck.


• The patient must avoid excessive flexion of the lower cervical spine and translation motion of the vertebrae that can occur if the patient is attempting to bring the chin to the chest. He or she must not lead with the face, as if looking upward, because that motion is cervical extension.


• The patient must flex the thoracic and lumbar spines to the limit of their flexibility and maintain this position as he or she completes the hip flexion motion (sit-up).





Special Considerations




• Patients with a thoracic kyphosis should not perform this exercise because it emphasizes maximum thoracic flexion. This exercise is contraindicated for patients with osteoporosis because the trunk flexion increases their risk of compression fractures.


• This exercise is contraindicated for patients with cervical disease because of the stress on the cervical spine.


• This exercise is contraindicated for conditions in which compression of the lumbar vertebrae is undesirable, such as low back pain.


• Patients with spondylolisthesis should not perform the hip flexion phase.


• Patients with excessive lumbar flexion should be carefully monitored and should do the exercise with their hips and knees extended.


• Patients with very limited spinal flexion should not do this exercise because of the exaggerated hip flexion phase. (The duration of the hip flexion phase exceeds that of the trunk flexion phase.)



Hip Abduction/Lateral Rotation From Hip Flexed Flexed Position




Correct Performance



Level 1:



• The patient starts with one hip and knee extended and the other hip and knee flexed. He or she places the hands on the pelvis (in the region of the ASIS) to monitor any motion. The patient is instructed to contract the abdominal muscles by “pulling the navel in toward the spine.”


• The patient lets the flexed lower extremity move slowly into hip lateral rotation/abduction. The patient stops when he or she experiences symptoms or feels the pelvis begin to rotate. If the pelvis remains stationary, he or she allows the hip to abduct/laterally rotate as far as possible by relaxing the adductor muscles. The patient adducts and medially rotates the hip, returning to the starting position.


• The patient repeats the exercise, trying to increase the hip range while preventing pelvic rotation by contracting the abdominal muscles. The exercise can be repeated with the same extremity before switching to the contralateral lower extremity.



Special Considerations


If the patient has minimal abduction without pelvic motion or has pain, it might be necessary to put pillows along the outside of the leg to allow the leg to relax against a support to prevent pelvic motion or pain.



Level 2.: When the patient is able to perform the full range of motion without pain or pelvic rotation, the following progression is suggested:



The patient contracts the abdominal muscles and lets the flexed lower extremity move into abduction/lateral rotation. At the end of the range, the patient extends the knee followed by hip flexion/adduction, returning the leg to the midline and flexing the knee to return to the starting position. The patient repeats the exercise 5 to 10 times with one extremity, and then the exercise is performed with the other lower extremity.



Straight-Leg Raises (Hip Flexion With Knee Extended)




Correct Performance




A Knee extended with hip flexion and return to starting position


Related posts:

Movement Impairment Syndromes of the Hip Concepts and Principles of Movement Movement Impairment Syndromes of the Lumbar Spine Movement Impairment Syndromes of the Shoulder Girdle Lower and Upper Quarter Movement Impairment Examinations Exercises to Correct Movement Impairment Syndromes

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Sep 1, 2016 | Posted by in RHEUMATOLOGY | Comments Off on Corrective Exercises: Purposes and Special Considerations

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