EFFECTS OF VERTEBRAL ROTATIONAL DISPLACEMENT
- By having the spine twisted in a certain direction; for example, by overshooting the mark on a particular sports manoeuvre, or having an opponent move one’s head and neck or the trunk/pelvis too far in a certain direction in a wrestling match (Fig. 14)
- As a result of asymmetrical tension in pairs of ligaments or muscles that have attachments to the vertebrae. For example, the iliolumbar ligaments and the flank muscles (psoas major/minor and quadratus lumborum)—all of which have attachments to L4 and L5—are in a position to pull excessively on one side of these vertebrae and cause a rotational displacement (Fig. 15).
Because of some anatomical features of the discs and facet joints, a displaced vertebra, in fact, ends up not only being rotated but also angled to one side and leaning either slightly forward or backward, all at the same time (Fig. 16). These changes result in increased stresses on the facet joints, discs, and the muscles and ligaments that connect the vertebrae at the levels involved (Figs. 13, 16).
Rotational displacement is commonly seen in association with pelvic malalignment and can affect any vertebra from C1 at the top to L5 sitting on the sacrum. However, athletes and those involved in their care should be aware of the levels commonly involved when pelvic malalignment is present, as they are more likely to become a problem in sports.
- L4, L5, or both vertebrae: Displacement is marked by the sudden onset of a very severe to excruciating low back pain, maximal at the base of the spine, with possible referral to distant sites by any soft tissue and nerve structures affected.
- T11, T12, L1: Degenerative changes at the junction of the thoracic and lumbar spine in the mid-back region are commonly seen in athletes participating in sports that call for:
- repeated high spine loading (e.g., when doing a jump; on taking off or landing) and/or having to bend forward or backward at high speed (Fig. 17)
- rotation of the trunk on the pelvis or of both to the same side or in opposite directions (Figs. 1, 9, 18). Involvement at these levels is more likely in gymnastics, ballet, wrestling, diving, water- ski jumping, and with the bowling action of cricket. The stress on the site of reversal of the compensatory curves at the T12–L1 junction usually present as mid back pain (Fig. 19: mid “x”). However, irritation of nerve roots in this area can also trigger a thoracolumbar syndrome, with pain or abnormal sensations felt in the low back/buttock, groin, or outer hip region (Fig. 20).
- T4, T5: These levels, lying between the shoulder blades (Fig. 21), are subjected to the forces created by arm and trunk actions. Stresses are aggravated by any rotational displacement of one or both vertebrae (Fig. 16), also from a lower than usual reversal of the compensatory thoracic curve that sometimes occurs at these levels (Fig. 21B). The pain is commonly felt in between and/or underneath one or both shoulder blades and may be referred in a pattern typically associated with angina or a heart attack:
- directly forward, through the chest, presenting as pain deep within or at the front of the rib cage
- to the shoulder girdle and down one or both arms
- The “T3” or “T4” syndrome: This refers to a complex of symptoms caused by the rotation of one or more vertebrae between T2 and T7, with T3 and T4 being most commonly involved. Onset in some cases has been noted following trauma (e.g., a fall onto the shoulder or direct insult to the front or side of the rib cage). The symptoms are vague and widespread and may include pain and/or abnormal sensations in the arms in a glove-like distribution, weakness of grip, a pressure feeling over the skull, arm swelling and discolouration that reflects effects on the autonomic nervous system, pain felt in the front of the chest wall and/or arm pit region, and sometimes difficulty breathing.
Minimal rotational displacement of a vertebra is most likely to become a problem with sports that require repeated rotation, bending either to the side, forward or backward, or a combination of these.
These sports include, in particular, gymnastics, weightlifting, rowing sports, throwing events, martial arts, court sports and others that involve a swinging motion (e.g., golf, field hockey, baseball, lacrosse, ice hockey). Whether or not such a displacement at a particular level actually becomes a problem depends on factors such as:
CORRELATION OF VERTEBRAL DISPLACEMENT TO SPORTS
THE ORIENTATION OF THE FACET JOINTS
The facet joint surfaces are orientated differently on comparing each of the three segments of the spine (Fig. 22). As a result, these changes allow for mainly:
- Bending forward and backward in the low-back (lumbar) segment, while restricting rotation and side-bending
- Rotation in the chest (thoracic) segment, while restricting bending forward and backward
- Rotation and bending forward and backward of the neck (cervical) segment, while limiting side-bending
ANY ADDITIONAL STRESS PLACED ON THAT LEVEL BY A SPECIFIC SPORT
For example, with the formation of the compensatory curves of the spine or abnormal rotational displacement of individual vertebrae:
BENDING FORWARD AND BACKWARD REPEATEDLY IN A STRAIGHT LINE
This symmetrical movement does not usually cause a problem with an activity such as sculling or working out on a rowing machine. The deciding factor here is the degree to which the athlete has to bend backward.
- If they bend the trunk back far enough, they’ll eventually put pressure on the facet joints in the thoracic segment, where they are oriented in a way that limits bending backward while allowing for increased rotation to right and left (Fig. 22).
- The farther they bend backward, the more pressure they’ll put on the surfaces of the facet joint on the side on which these have already been moved closer together because of the rotational displacement of a vertebra (Figs. 13, 16), degeneration of a joint (Fig. 23), or the concave (inner) part of a compensatory curve.
- At some point, the increased pressure put on the surfaces may prove too much, so that the affected facet joint finally starts to become painful. It is then also at increased risk of suffering a stress fracture.
The ribs attaching to each side of the rotated vertebra are increasingly vulnerable as one bends backward, given that the rotation simultaneously displaces the ribs, moving one forward, the other backward, and rotating them in opposite directions (Fig. 16).
PUTTING AN ADDITIONAL ROTATIONAL STRESS THROUGH THE LEVEL(S) AFFECTED
This is more likely in sports with a rotational component (e.g., tennis, gymnastics). The lumbar segment is particularly vulnerable, because its ability to rotate to the right or left is already restricted by the normal orientation of the facet joint surfaces.
Most of the movement on trunk rotation in sports such as golf, baseball, and hockey occurs through the thoracic segment and, if one allows it, also the neck (cervical) region. This rotation results in stress, particularly at the junction of the thoracic spine with the cervical segment above, at the base of the neck, and the lumbar one below, in the mid back region (Fig. 19: upper + mid “x”, respectively). Some limited rotation through the legs is usually also possible.
The pelvis is now unable to move or is “fixed.” Rotation of the trunk again occurs mainly through the thoracic segment and will stress the mid-back region in particular. Once no further rotation is possible through the thoracic levels, the lumbar spine will start rotating as one segment, but this rotation is limited and quickly results in increased stress on the low back.
- Sculling and rowing, which are symmetrical type of activities, as long as going straight forward/backward is within a range that does not stress a tender structure or put additional pressure on a facet joint whose surfaces have already been brought closer together on one side because of the malalignment.
- Sweep-rowing in a way that avoids the effects of any restrictions. For example:
- always pulling the oar through on the right or left side, whichever one allows them to go through a greater range of motion
- when canoeing, maintaining the kneeling position rather than sitting, because that allows them to rotate through the length of the spine, the pelvic region, hip joints and, to a limited extent, even the thighs (Fig. 24: R).