Full Ball & Socket Joint Description. [Continued from above] . . . In the shoulder joint, the spherical head of the humerus (upper arm bone) fits into the glenoid cavity of the scapula (shoulder blade). The glenoid cavity is a small and shallow cavity that permits the shoulder joint the greatest range of motion in the human body.
Lumbar lordosis refers to the inward curvature of the spine just above the buttocks. The National Institutes of Health reports that lordosis is caused by spondylolisthesis. Spondylolisthesis is a condition in which a spinal bone slips out of its normal space and onto the bone below it.
Loss or cervical lordosis simply means that your neck is straightening, losing the normal, healthy curve and optimum positioning. The result of this, for me, is that my head often feels heavy and forward-leaning, like a bowling ball in front of my body. This causes increased strain on my neck/shoulders, poor posture, and terrible headaches. Fortunately, as I understand it from my rheumy, this is not necessarily a permanent condition. I do proper neck exercises and stretches (there are some good ones on this site) to try and better my neck posture, and continue my medicine to combat the inflammation and reduce the muscle spasms.