Healthy joints 101

Keeping your joints healthy is important so that you can remain physically active and do all of the things that you like to do. If you’re looking to learn more about joints and keeping them healthy, check out the below frequently asked questions answered by Tufts Medical Center physical therapist Nikki Guerin, PT, DPT.

What is a joint?

The joints are where two or more bones meet, held together by ligaments with a cartilage cushion in between. In the human body there are many different types of joints that provide different amounts of mobility. The major joints in your body include: shoulder and hip, which are ball and socket joints; knee, elbow, wrist, and ankle, which are described as hinge joints.

What can go wrong with joints?

Joint injuries fall under one of two categories, traumatic joint injuries and non-traumatic joint injuries, also known as over-use injuries.

Traumatic injuries generally include a high velocity, high force impact (ankle sprain, slip and fall, or blow to the joint in a contact sport). This impact can cause the ligaments in the joint to get stretched or “sprained” and the muscles and tendons in the joint to get stretched or “strained”. It is possible for your ligaments, muscles, and tendons to get torn in more severe injuries.

In non-traumatic or over-use injuries, the tendons can become irritated (“tendinitis”), or the cartilage can wear down (joint degeneration). These types of injuries can also occur from muscle imbalances and poor mechanics at the joint leading to wear and tear on different tissues.

Traumatic and non-traumatic injuries can both cause swelling inside and around the joint.

Joint problems usually only affect older people, right?

No. Both traumatic injuries and over-use injuries can occur at any time. Over-use injuries are more commonly seen in adults than children, however they can happen whenever an individual is repetitively doing a motion without good joint mechanics. For instance, swinging a golf club or tennis racket or pitching a baseball repetitively over time with poor body mechanics can lead to these types of injuries. Joint mechanics are affected by imbalances in muscle strength and muscle length, as well as posture.

How do I keep my joints healthy?

Keeping the muscles that surround the joints strong is the best way to keep the joint itself healthy, as well as using proper alignment and mechanics with all activities. To keep joints working properly it is important to keep the muscles on either side of the joint strong. Examples of this include strengthening the quadriceps and hamstrings for the knee or at the shoulder including exercises for both the back, chest , and rotator cuff muscles. Muscle length is also a factor in mechanics so remembering to stretch muscles on both sides of joint is equally as important as strength, as flexibility is equally important as strength when it comes to fitness to ensure proper joint alignment and mechanics.