David Alonso Calderón
The lack of stability or “instability” of the lumbar spine must be different from hypermobility. In both, the range of motion is more significant than average. However, instability is present when this excessive movement accompanied by a lack of “protective” muscle control (Maitland 1986). Both situations are usually the cause of many lumbar pains.
Three different systems determine the stability of the spine: the passive that refers to non-contractile tissues, the active one seen to contractile tissues (muscles), and the neural control related to the nervous system.
As an objective in the rehabilitation process, we must achieve a restoration of active lumbar stabilization; so that the final phase is to convert the conscious control of movements (cortical route) into an unconscious level (subcortical pathway).
This is achieved by an increase in sensory stimulation, improving the activation of subcortical systems and, therefore, the speed of muscle reaction.
In many programs of prevention or treatment of low back pain, abdominal exercises are widespread in which the trunk flexion (incorporated, sit-up) predominates with or without rotation, or elevation of the leg, using the mobilizing abdominal muscles mainly. However, one of the critical functions of the abdominals is to stabilize the spine.
We could classify the trunk muscles in:
- Mobilizers: rectus abdominis, lateral fibers of the external oblique and spinal erector
- Primary stabilizers: transverse abdomen and multifidus
- Secondary stabilizers (can also mobilize joints): internal oblique, medial fibers of the external oblique, and the lumbar square.
The transverse abdomen and oblique abs play a fundamental role in lumbar stabilization, due to its relationship with the thoracolumbar fascia; when inserted into the vertebrae through it. The therapeutic objective is, therefore, to activate the stabilizing muscles (transverse of the abdomen and internal oblique) by isolating them from the action of the abdominal rectum and the external oblique.
The first phase would be to re-educate the action of the transverse abdomen, obtaining an isolated contraction of the stomach concerning the abdominal rectum that often predominates. (Sullivan 1997) showed that in patients with chronic low back pain, the use of the internal oblique was reduced for the abdominal rectum and the external oblique, reflecting a change in the motor activity model.
To achieve this reeducation, it is beneficial to use the technique of pushing the abdominal inward. You can start from the position of four points (resting hands and knees on the floor) is usually the easiest for the patient, and then move to a standing position on the wall. The spine must be in a neutral position, controlling the alignment of the physiotherapist and correcting the pelvic tilt.
In this way, the patient is asked to push the belly button in and up while breathing normally. Different visual indications or “feedback” are used, looking in a mirror, or tactile, palpating the abdominal region. Another method of facilitation is telling the patient to cough (increases visceral pressure) and to maintain contraction. The contraction is held for about 10 seconds, and ten repetitions are done. Slow and low-intensity contractions must be used.
The action of pushing the abdominal “in” must be differentiated from the retroversion of the pelvis, ensuring that patients do not force their backs back through this retroversion through the rectus abdominis.
Once you have a mastery of the technique, you work the same but without leaning on the wall; without any movement of the spine or pelvis.
The next phase is progressed through exercises to achieve a static lumbar stabilization. Work begins in a prone position, including leg movements. The previous contraction of the transverse is maintained in all the activities. Slowly one leg is stretched, sliding the heel on the floor. If a pelvic anteversion is caused and lordosis increases, it turns back to flexion. The exercise progresses, placing the hips in 90º flexion, subsequently, raise the lever arm and lift the leg, resting the other on the floor.
Other variants make progress exercises include movements of arms above the head, and you always have to influence the lumbar stabilization to remain.
This second phase is based on the gradual increase of the load in the stabilizing muscles through a series of exercises that follow a pattern of postural control.
These same exercises can also be practiced in lateral recumbency, in quadrupeds, or resting with the knees on the floor and the tips of the feet, in which small imbalances are caused.
The “bridge” exercises (raising the pelvis from the ground) are also practical; since there is a co-contraction of the abdominal muscles, spine extenders, and hip extenders. Muscle activity patterns associated with lumbar stabilization are achieved.
Stabilization exercises can be combined with stretching of the muscles that have been observed to be shortened (such as hamstrings, iliotibial band, or iliac psoas) while maintaining the neutral position of the spine.
The last phase will seek for the patient to gain sufficient voluntary control of his pelvis, thus placing it in different ranges of movement, but avoiding varieties in which the tissues are under stress. In this way, progress is made to dynamic stability.
In this phase, the initial positions may be the same as in the previous one. The patient seeks to “explore” the movement of his spine.
All kinds of proprioceptive exercises are included in this phase; and those who make use of the “Swiss” ball. To the practices you can add actions such as: make circles with the pelvis, movements of the arms or legs in multiple planes, help with elastic bands
When planning a lumbar stabilization program, we should not forget the back muscles of the trunk, the multifidus in its role of stabilizers, and of the other stabilizing muscles considered “secondary” (lumbar square, wide dorsal and back retractors); the latter especially in the last phases.
The activation of the multifidus is achieved using rhythmic stabilization techniques in various positions. For example, in the prone position with knees inflection, it is pushed on the knees, trying to make a rotation, while the patient resists movement. Another exercise, for the same purpose, and starting from the same starting position, but this time was pushing with the knees a ball against the wall.