Sciatica and lower backache can be grouped together as they share similar etiology. Several million workdays are lost each year due to back pain. The back is the realm of the kidneys I differentiate a chronic from an acute condition based on six categories of etiology. Excessive physical work (i.e. lifting type injuries) excessive sexual activity, PG and childbirth, invasion and retention of external wind, cold and dampness (people who work outside for decades and wear short jackets for access to their tools often develop low back problems over time) overwork, meaning long hours without adequate rest over many years depletes kidney yin. Which in turn fails to nourish the back and leads to chronic back issues. Inadequate exercise coupled with poor posture and overeating/drinking contributes to back problems. These conditions respond well to acupuncture and oriental medicine.
There can also be kidney organ disease. This is not thought of as a channel or meridian problem, although there may be concurrent physical symptoms. In acute issues such as nephritis there will be obvious symptoms and signs such as fever malaise, edema in the face, headache, scanty dark urine. Chronic cases will have protein in the urine, edema in the ankles, exhaustion or extreme fatigue. Kidney stones generally have severe colicky pain radiating from the low back to the groin. These conditions require a different treatment plan based on differentiating the pattern of presentation. Again, history of the chief complaint, diet, and lifestyle has a direct affect on these conditions.