Have you ever wondered what the difference is between a sprain and a strain? These terms are often used interchangeably, and while they can occur simultaneously, they are actually two separate entities.
By definition, a sprain is an injury to a ligament. Ligaments are short bands of tough, but flexible, fibrous connective tissue. They connect bones (or cartilage) together, and therefore hold joints together. By contrast, a strain is an injury to a muscle and/or a tendon. Tendons connect muscles to bones.
We grade both sprains and strains in a similar fashion: grade I is an overstretch or slight tear, with mild tenderness, swelling and stiffness; grade II is a larger, but incomplete tear, with moderate pain, swelling and often bruising; grade III is a complete tear, with severe swelling and bruising as well as instability.
The most commonly sprained joint is, of course, the ankle. The most common ankle sprain is an inversion sprain, in which the foot rolls inward & overstretches the outside or lateral ankle ligaments. (If you look at your ankle, you’ll see why: the outside or lateral malleolus – the bony prominence of the ankle – is lower than the inside or medial malleolus, thus giving more bony stability to the outside of the joint.)
Sprains and strains can affect the spine as well. Patients often ask if their injury is to the muscles or the joints of their spine. Our most common answer? Yes! Because muscles attach to vertebrae (the bones of the spine), injuries commonly affect both the muscles and the joints. The joints between the vertebrae, called facet (pronounced “fuh-set”) joints, are very pain-sensitive. They are subjected to misalignment and irritation (known as subluxation or intersegmental dysfunction). Treatment, therefore, usually addresses both the skeletal and muscular components.
We’ve talked in the past and will talk more in the future about treatment of sprains and strains and subluxations. For now, armed with your new knowledge of sprains and strains, you can listen to your favorite sports teams’ announcers confuse the two. And when Bob says “I think he strained his ACL, Frank”, you can do what we do, and snarkily say “you sprain a ligament, Bob, not strain it!” If you’ve really got your snark on, you can explain to Bob the difference between “arc” and “arch” – but that’s another article…