The elbow is a hinge joint that connects the humerus, the bone of the upper arm, with the ulna and radius, the two bones of the forearm. When people refer to the “inner elbow,” they are pointing to the side closest to the body, which anatomically is known as the medial aspect. This region is a dense intersection of bone, muscle, nerve, and ligament structures, making it prone to specific types of injury and discomfort. Understanding the proper terminology for this area helps medical professionals accurately diagnose and treat conditions unique to the inside of the joint.
Anatomical Identification of the Inner Elbow
The precise bony landmark representing the inner elbow is the Medial Epicondyle. This is a prominent bony knob found at the end of the humerus. The term “medial” signifies that this structure is located toward the midline of the body. The medial epicondyle serves as the common attachment point for several muscles responsible for movement in the forearm. Specifically, it is the origin for the powerful group of flexor muscles that allow the wrist and fingers to bend toward the palm. This concentration of muscle attachments means the medial epicondyle bears significant stress during activities that involve gripping or repetitive wrist motion.
The Ulnar Nerve and Other Key Structures
Directly behind this bony prominence lies the ulnar nerve. The ulnar nerve travels through a narrow passageway known as the cubital tunnel, which is bordered by the medial epicondyle. When this nerve is struck against the bone, it produces a distinct, shock-like sensation commonly referred to as “hitting the funny bone.” The nerve provides sensation to the ring and little fingers, as well as controlling many of the small muscles in the hand. Prolonged pressure or repetitive bending of the elbow can irritate the ulnar nerve, a condition known as cubital tunnel syndrome.
Also residing in this region is the Medial Collateral Ligament (MCL), which provides stability to the inner elbow joint. The MCL, also called the Ulnar Collateral Ligament (UCL), is the primary restraint against sideways stress on the elbow, especially during overhead throwing motions.
Understanding Medial Epicondylitis
A common painful condition affecting the inner elbow is Medial Epicondylitis, often known as Golfer’s Elbow. This condition involves degeneration or micro-tearing of the common flexor tendons where they attach to the medial epicondyle. It is primarily an overuse injury resulting from repetitive forceful movements, particularly those involving wrist flexion and forearm pronation. Symptoms typically include pain and tenderness concentrated directly over the medial epicondyle, which may radiate down the forearm. Discomfort is often worsened by activities such as gripping or lifting objects. While it shares similarities with Lateral Epicondylitis (Tennis Elbow), Medial Epicondylitis affects the flexor tendons on the inner side, whereas the lateral condition affects the extensor tendons on the outer side.