Sciatica is radiculopathy resulting in symptoms which effect the leg.
Picture-Lumbar intervertebral disc impinging on nerve root (source-Blausen.com)
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 the following affecting the arms, 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 intervertebral 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.