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Anatomy 101: A Thrower’s Arm

On average 50% of baseball and softball players experience a throwing-related injury.

According to the American Sports Medicine Institute,

“The 2014 National Electronic Injury Surveillance System reported 130,376 emergency room visits due to baseball/softball related shoulder, elbow, trunk, lower arm, head, neck, ankle and facial injuries.”

First and foremost, the main goal of training should be to keep athletes healthy, best acquired with a comprehensive approach. This should include a sport-specific strength and conditioning programming, shoulder and elbow care programming, and an in-depth educational process. Education is imperative to help athletes understand how to take care of their arms in the gym and on the field.  Although we as coaches can provide the tools needed to maintain a healthy body and arm, you as the player, are the one ultimately responsible for consistently putting in the detailed work that leads to its manifestation.

A Throwers Anatomy

The first step to this education process is some anatomy background. Let’s start with the most important joints, ligaments, muscles and nerves involved with maintaining arm health. First, we will start with the elbow joint itself. The bones that make up the elbow are the Radius, Ulna, (Forearm bones) and Humerus (Upper Arm Bone). Ligaments connect bones to each other. The most important one at the elbow is the Ulnar Collateral ligament; notorious for being the ligament that requires “Tommy John” surgery to fix when it tears. This ligament’s main job is to resist the stress created by throwing.

The muscles that help protect the elbow during throwing are a group called the Flexor Pronator Mass and the Supinators. They are the muscles that help you move your wrist. Lastly, the ulnar nerve is the nerve that runs the length of your arm. When you hit your “Funny Bone,” you are hitting your ulnar nerve.

Injury Prevention

“Injury is the disruption of tissue, that may or may not lead to a decline in performance.”

A disruption of tissue is any change of the muscles, tendons, ligaments or bones that were listed above. The key to this definition is that injury doesn’t always lead to a decline in performance.

Put another way, although you might be able to continue to play, throw hard, get hitters out, or command your off speed, you might still be doing damage.  This is because injuries happen over time.  An injury experienced at age 21 is rarely a random, independent traumatic experience; the ball probably got rolling at age 13 or 14.

When throwing, the most important part of injury prevention is keeping the ball in the socket. There are several parts of the shoulder that are responsible for this. The first is a small piece of tissue called the shoulder labrum. Next in line is a set of muscles called the rotator cuff. These muscles are commonly called your arm decelerators. And lastly, the biceps brachii also help keep the ball in the socket. Each of these structures are areas that can be injured during the throwing motion.

Take a moment and think about how your arm feels during or after you throw. Are there any spots that get sore or bother you? Is it your elbow? Is it your shoulder? Do you get sore or painful while throwing or afterward? If any of these questions ring true to you try out these shoulder strengthening exercises or consider seeing a NAKOA Physical Therapist for the best possible treatment and care.

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