Ligaments are the connective tissue made up of collagenous fibers that attach bone to bone. Ligaments help stabilize joints with range of motion and sustain a tensile force. A ligament sprain often occurs when there is a traumatic joint injury. The body’s natural healing process for a ligament sprain can be divided into three stages. First, the ligament ends retract and a hematoma is formed. Then scar tissue is formed over the course of a few weeks. The third stage consists of matrix remodeling in which the scar tissue is replaced by proteoglycan and collagen. Ligament injuries are most common in the ankles, wrists, shoulders, and knees including AC joint separations, the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL) injuries. Depending on the severity, ligament injuries can be classified into three degrees.
A first-degree sprain is the least severe. There is typically little tearing, pain or swelling, and joint stability is still good. It usually takes 1-2 weeks to heal.
A second-degree sprain has the broadest range of damage with moderate ligament tear, moderate instability and moderate to severe pain and swelling. Recovery may take 3-6 weeks.
A third-degree sprain is the most severe. The ligament is completely ruptured, the joint is unstable, and there is severe pain and swelling. They often need surgical repair. Recovery requires 8-12 months.
Skeletal muscles consist of an arrangement of fibers that are connected to tendons. Each muscle fiber is made up of cylindrical muscle cells called a myofibril. Muscle tears occur when muscle fibers are damaged due to muscle overloading or fatigue. The natural healing process of a muscle tear also occurs in three stages. First, the ruptured myofibers contract and form a hematoma. Then myogenic reserve cells are activated and begin repairing the damaged myofibers. In the third stage, the regenerated myofibers mature and the remodeling phase is complete. Muscle tears are most common in the hamstrings, quadriceps, calf, and back.
A first-degree strain indicates the least severe damage with little muscle tearing and mild tenderness. There is also mild pain with full range of motion. Recovery takes about 2-3 weeks.
A second-degree strain occurs when the muscle has been torn and about 80% of tissue fibers have been ruptured. There is usually more pain, edema, and bruising with swelling caused by the broken blood vessels; range of motion is also significantly reduced. Typically, it takes 2 to 3 weeks to have any improvement in the pain and swelling and 3-6 weeks for a full recovery. It is common for athletes to resume their activity too soon afterward and easily becomes a third-degree injury.
A third-degree strain involves completely ruptured muscle tissues. The area of the body is no longer functional. There is usually visible bruising, pain, and the possibility of an avulsion fracture. They often need surgical repair and require at least 3 months of rehabilitation after surgery.