The main difference between a sprain and a strain is that strains are injuries that are confined to the muscle and sprains effect the other soft tissues around the joint as well as the muscle.
Both can be painful but strains do not effect the stability of the joint where sprains do. A strain can tear a muscle and cause restricted movement but fortunately muscles have a rich supply of blood and therefore oxygen which means they heal faster than sprains do.
Sprains by definition can not only tear muscle but also damage the ligament, tendon and cartilege, these tissues have a poorer supply of oxygen and take longer to heal. Muscle is red because it has alot of blood inside it, ligament, tendon and cartilege are white because they contain less blood.
Sprains are graded according to the severity of the damage done, a grade 3 sprain is a complete disruption of stability of the joint where the ligament is torn away completely, when this happens to your knee good early splinting may be enough to set it on it’s course to healing but if this doesn’t work surgery may be the best option. A grade one sprain on the other hand does not disrupt the ligament and can be indistinguishable from a strain. Grade 2 spraining is in between one and three, partial ligament damage causes slight instability and if you are careful not to re-injure yourself will generally not require surgery.
Sprains to the ankle are one of the most common and although they can be severe you have a better chance of avoiding surgery than an equivalent knee sprain.
Ice packs to your freshly sprained joint or strained muscle is usually good first aid, anti-inflammatories can help too just remember that though the pain is diminished the damage is still there so an immediate return to the activity that caused it is unadvisable.
Interferential, ultrasond and laser acupuncture directly to the injured area can be effective treatment. Massage, acupuncture, osteopathy, physio and chiropractic can be used on the injury site when the inflammation fades (when redness, swelling and touch sensitivity subsides) and can be used to contain the problem in the short to medium term.
Ignoring sprains and strains will not make them go away unless it is only mild damage, when you are limping and favouring one side the other leg joints on both sides of your body are used more and in a lop sided way. If your knee, hip or lower back starts to inexplicably become stiff or painful weeks or even months after your sprain or strain there is a good chance it could be related.
No matter what therapy you choose a practitioner who takes a “global” approach protecting your other leg joints will help you most.