Nerve roots are paired bundles of nerve fibres, as they leave the spinal chord, before they form nerves. The nerve roots exit the spinal chord via intervertebral foramina (gaps) between adjacent vertebra. Cervical radiculopathy will result in some, or all, of pain, tingling/pins and needles, numbness, and weakness of certain muscles, the exact pattern of which is dependent on which nerve roots specifically are compromised. There may also be lack of coordination with hand use. A healthcare professional may also comment that, if examined, certain reflexes are weak or absent.
The causes of cervical radiculopathy vary, and may include disc herniation or degeneration, general age related degenerative changes such as spondylosis, or temporary irritation of facet joints.
As well as differentiating from certain systemic causes, cervical radiculopathy needs to be differentiated from other conditions, such as peripheral neuropathy, e.g. Carpal Tunnel Syndrome, or Thoracic Outlet Syndrome.
Radiculopathy also occurs in other regions of the body apart from the neck, for example, sciatica, with symptoms affecting the legs.
There are various types of RSI. These are, as the name suggests, caused by cumulation of repetitive movements which may be large, such as those involved in sports, or small, such as typing, use of a computer mouse, or tool use.
Two of the most common forms of RSI are lateral and medial epicondylitis. Lateral epicondylitis or tennis elbow, does not commonly, despite it's name, result from playing tennis. The majority of cases are among office workers/computer users, or other people who make small repetitive movements, e.g. screwdriver, or other tool, use.
The lateral epicondyle is a bony prominence of the humerus (upper arm bone), and is located, if you stand with your arms at your side with the palms of your hands facing forward, on the outside of your elbow. The muscles which act to extend the wrist and fingers attach, via tendons, to the lateral epicondyle. Degeneration of these tendons can occur, particularly (due to poor blood supply) near the point which they attach to bone. This results in pain in the area of the lateral epicondyle, and, often, forearm, and possibly reduced grip strength. Often there is involvement of the shoulder region, particularly of one of the biceps tendons.
Medial epicondylitis is a similar condition, but with the pain affecting the medial epicondyle on the inside of the elbow, and affecting the muscles which flex the fingers and wrist.
Other forms of RSI include Thoracic Outlet Syndrome (TOS), Carpal Tunnel Syndrome (CTS), various forms of tendinosis (degeneration of a tendon without inflammation), and, less commonly, tendinitis (tendon injury with inflammation).
Picture-Lateral Epicondylitis/Tennis Elbow (source BruceBlaus)
The sacroiliac joints are a pair of joints located below the lumbar (small of back) region of the spine, between the sacrum of the spine, and the ilium of the pelvis. These are large joints, strongly reinforced by various ligaments, which allow a small amount (a few millimeters) of movement. The functions of the sacroiliac joints include shock absorption/force transference from the lower limbs (legs) to the body, and vice versa, stability during the push off stage of the gait cycle (walking), as well as allowing widening of the pelvic girdle while giving birth.
Dysfunction of the sacroiliac joints results in their irritation, and may occur from too little, or too much, joint movement. This may be due to repetitive small movements, or a larger traumatic force, e.g. stepping off a high pavement unexpectedly. Sacroiliac joint dysfunction is common in pregnancy due to the actions of hormones on the ligaments which surround the joint, combined with the extra strain of increased weight during pregnancy. While, generally, patients do not suffer repeated sacroiliac joint dysfunction, there are, for example, biomechanical reasons which may cause this.
Sacroiliac joint dysfunction is one of the most common causes of low back/buttock pain, and may refer pain to the back of the thigh and groin. Very occasionally pain may be felt below the knee.
Picture-Sacroiliac joint from behind (source-Blausen.com)