The asymmetry of this pose makes it very revealing about the ‘sidedness’ exhibited in the back muscles. Janu sirsasana can also reveal sidedness in the relative stability or mobility of the sacroiliac joints. Everyone has an “ease” and a “hard” side in this pose because of the inherent asymmetries of the human body.

The more mobile the sacroiliac joint is on the side of the flexed leg, the easier it is to turn and face the extended leg. This is especially true as the spine extends toward the extended leg. As hip flexion deepens, less spinal flexion is required. Because this limits even further the rotation in the lumbar spine, more movement needs to happen at the sacroiliac joint.

It is very common to over-mobilize the sacroiliac joint in janu sirasana. This happens when the pose is pushed or flexed too forcibly or held for too long without relieving the weight on the pelvis Alternatively, immobility of the pelvic joints can lead to excessive torque in the bent-leg knee joint. Many yogis report meniscus tears occurring as they move into this pose. This happens in a partially flexed knee as the pelvis flexes forward, taking the femur with it, which grinds the medial femoral condyle into the medial meniscus. Ensuring that the bent leg is truly flexed will move the meniscus safely to the back of the join.

All this points to the fact that potential stresses of the spine, sacroiliac, and hip and knee joints need to be evenly distributed so that no one structure takes all the force of this pose.