Formerly the sacred bone was considered as something divine and sacred since it was the last bone to decompose, hence sacred means sacred. In addition it was also considered to be one more vertebra, but in this case an important vertebra that exerted support for the rest of the spine.
Our ancestors were not at all wrong since the sacroiliac joint plays a fundamental role for both the spine and the pelvic function. Think that the triangular shape of the sacrum provides a mechanical advantage to dissipate and withstand forces. Given its position and its powerful muscular protection, when pain is felt it is difficult to identify exactly which is the painful area. That is why you need to have a basis for the anatomy and functioning of this joint to prevent and treat possible pain problems in it.
What is the anatomy of the sacroiliac joint?
It is well known that the anatomy and biomechanical function of the sacroiliac joint is extremely complex, nevertheless it is necessary to know some basic aspects.
- Like all articulation, the sacroiliac joint is mobile, although not too much.
- Its direct connection to the pelvis makes it very well protected by a large number of ligaments and muscles such as the psoas, the iliac, the spinal erectors, the lumbar square, the piriform, the obturator, the obliques, the abs, the buttocks and the ischiosural.
How many muscles do you? Well, imagine that if there is no balance in the muscle length it will provoke, among other consequences, limitations in the joint movement that will affect the pelvis and, obviously, the knee.
What is the function of the sacroiliac joint?
As mentioned previously, the triangular design of the joint provides a structure that helps dissipate forces. However, it also helps to transmit forces from the lower limbs to the upper limbs and vice versa. In fact, an important investigation showed that during a hip, knee and ankle flexion (ie, a traditional squat) the forces transmitted by the sacroiliac joint were 27 Kg
What movements can the sacroiliac joint exercise?
There are two fundamental movements of the joint that you may not know:
- Nutation: This movement focuses on your sacrum causing a forward advance and inclination. Since it is connected to the pelvis, this movement involves an internal rotation of the femur.
- Contranutación : It is an opposite movement, causes a recoil and a decline of the coccyx. In this case, the femur is in external rotation.
What problems can arise in the sacroiliac joint?
Now that you know a little more about this articulation, it is time for you to be aware of what problems can be triggered in this body area. There are four main problems:
- Rigidity and muscular shortening.
Among the problems mentioned, there is a cause as a common denominator, muscle imbalance. As mentioned above, if some muscles work more than others, they will cause problems. For example, hypermobility (between 30% and 86%) occurs during pregnancy, as separation of the ischia occurs.
Obviously this is necessary since space must increase for a simple reason: there is a baby that must pass through there. The negative consequence is that if you have not trained previously, after giving birth it will be more difficult to recover muscle strength, causing pain, in addition to instability. That is why 15-25% of women have postpartum pelvic pain.
Another clear example is that when the gluteus maximus is weak, since it does not help to stabilize the joint. This causes the femoral biceps to tense more due to its direct relationship with the sacrotuberous ligament. And do not forget how important it is to have a correct stabilization of the thoraco-lumbar fascia to keep the joint stable.
How can I prevent and treat pain in the sacroiliac joint?
Obviously, the first step you should take is to go to a physiotherapist or an expert who can make a good diagnosis. Believe it or not, this is important. For example, if you have a trigger point in the very long muscle, the pain will be felt right in the sacroiliac joint. The same happens with the gluteus minimus and the iliocostals . This means that the pain may come from another area that affects the joint. However, as a general rule, the following measures will help you:
- Train to have a strong glute.
- Do not forget to train the stability of the core. Now, 30 seconds or a minute doing an iron is not stability, with series of 10-15 seconds and a good technique is more than enough.
- Stretch to improve flexibility. Focus on the flexor and extensor muscles such as quadriceps, psoas, iliac, ischiosural and pyramidal. By the way, do not forget that less than 30 seconds stretching passively will not do you much good.