Third Cardinal Sign, Assessment for Right Leaning Scoliosis
A common pattern noted from early in my practice was tightness and tenderness on palpation of the right QL's. Of course there are many exceptions to this...it might be greater on left or present on both sides...but the most common pattern is the affected right side together with spasm and tightness through the left glutes. After several years practice I worked out the left glute thing being the effect of left hip rotation (First Cardinal Sign) on the SIJ impacting the back line of the lower limb. The tenderness and tightness through the QL's remained a mystery until much later when realising the impact of mild scoliosis, right convexity, on the lumbar vertebrae as a result of the LLD. The effect of right leaning tilt on the pelvis opens lumbar disk spacing to the right, encourages mild disk bulging and strain through the soft tissue.
In most cases, the degree of right leaning scoliosis present through the spine is mild. Virtually unnoticeable to visual inspection and the client is usually unaware of it. The client may never have been told of its presence. Yet it can be the cause for their history of upper back and neck issues of discomfort and tightness, pain and/or headaches. It can be cause for low back pain and disk bulging through the lumbar region. It is another piece of evidence supporting the fact a LLD exists.
Examining client in standing position, practitioner seated in front, place fingertip on top corner of each ASIS of the pelvis. The left side is typically superior in the range of 5mm to 10mm. Owing to hip rotation this is not indicative of actual LLD. It is the net effect of LLD less the adjusting action of forward rotation of the left hip. Exception cases not exhibiting the First Cardinal Sign will have higher range pelvic tilt. Similarly, palpating position of the Greater Trocanter eliminates the vagaries of hip rotation on LLD assessment but can be difficult to locate accurately, particularly on female clients who typically have greater amounts of flesh over the hip joint.
With client prone on the table, mild scoliosis is best observed by palpating the ribcage. The most common is right leaning scoliosis with convexity to the right through the Thoracic. Due to years and decades from the spine diverting sideways in the Frontal plane, pressing to the right, the costals bulge to the right and are stretched out and flattened the left. A greater degree of muscle development and tightness is present in the right spinal erectors. The right shoulder will be elevated over the left.
Less common is a right leaning pelvic tilt with a scoliosis exhibiting a left convexity through the Thoracic as a result of a switch back in the region of the lumbo-thoracic junction. Bulging of the left costals and flattened right costals will be evident. I find left convexity cases typically are low range LLD. The spines of individuals with smaller LLD's and reduced Pelvic tilt are not encouraged as strongly to the right and more likely to veer or flop the other way through the Thoracic. A larger LLD creating a steeper pelvic tilt, exerts a stronger right leaning force driving the spine to the right, resulting right convexity through the Thoracic.
Left convexity cases exhibit an elevated left shoulder, more highly developed and tighter spinal erectors on the left through the Thoracic and are more likely to experience dysfunction and pain in the upper left quadrant of the back.
Lastly, exposing the vertebrae of the spine by forward flexion through the torso clearly reveals diversion of the spine from side to side. I have not yet made a close study of this as I do not attempt spinal adjustment. While trained in release techniques to realign rotated vertebrae it is not a part of my regular practice. While effective, it did not have a lasting effect. Perhaps because the fundamental issues at the Pelvis due to LLD were not being addressed.