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Ligaments of the Elbow Stability and Elbow

Join this channel to support the channel https://www.youtube.com/channel/UCOHfqHMhHvfQCYJDXfpSAiw/join Ligaments of the elbow, stability of the elbow. The primary stabilizer of the elbow is the ulnohumeral joint. The coronoid process is the anterior buttress of the olecranon. The coronoid process prevents posterior dislocation of the elbow. Fractures of the coronoid process, more than fifty percent of the height, will lead to elbow instability. There is another fracture of the coronoid process that we need to recognize, and it is the anteromedial fracture of the coronoid process. If you have an LCL tear, which is a lateral collateral ligament tear, and an impaction fracture of the anteromedial coronoid facet, this will lead to posteromedial instability of the elbow joint. Sometimes this fracture is not easily seen on X-rays. The fracture can be missed. Delayed treatment of this fracture may result in varus and posteromedial instability and early onset of osteoarthritis. Surgical fixation should be done, and it is usually done through a medial approach. The posteromedial instability usually results from a varus deforming force. The coronoid process is also the attachment site for the important ligament, the anterior bundle of the medial collateral ligament of the elbow. Fracture of the coronoid process can also be part of the terrible elbow triad, an elbow dislocation associated with a radial head fracture and a coronoid process fracture. Now, let’s talk about the ulnar collateral ligament or the medial collateral ligament. The medial collateral ligament is composed of three bands: the anterior, the posterior, and the transverse bands or bundles. The most important one is the anterior band of the MCL. It is the strongest primary stabilizer to valgus stress at ninety degrees of flexion. In extension, it provides about thirty percent of the restraint. The osseous and articular components of the elbow joint, as well as the anterior joint capsule, resist valgus forces in extension. The MCL originates from the posteromedial epicondyle of the distal humerus. It inserts into the sublime tubercle of the medial coronoid process. Late cocking and early acceleration will give the highest valgus torque to the medial collateral ligament. Deficiency of this ligament is diagnosed with the moving valgus stress test or the valgus stress test. With the arm fully supinated, identify the MCL and take the forearm into full extension, placing a valgus stress on the medial collateral ligament. The elbow valgus stress test is used to assess the integrity of the medial collateral ligament. For MCL of the elbow, the clinical exam is not as good as the MRI. MRI is the best study to diagnose a complete tear of the MCL of the elbow. CT scan arthrogram is more sensitive than MRI for partial lesions. Treatment. In case of a complete tear, reconstruction of the medial or ulnar collateral ligament deficiency is the best procedure. What is the indication for surgery? Complete tear in a high-level throwing athlete, with ninety percent return to the pre-injury level of activity. The posterior portion of the MCL forms the floor of the cubital tunnel. The posterior bundle of the MCL is tight in elbow flexion. If you want to get more flexion of the stiff elbow, release the contracted posterior band of the medial collateral ligament. Here, there is a stiff elbow with decreased elbow flexion due to a tight posterior portion of the MCL. Now, we do release of the posterior band of the MCL, and by this, we increase the elbow flexion. The lateral collateral ligament complex consists of four parts: the lateral ulnar collateral ligament, the lateral radial collateral ligament, the accessory lateral collateral ligament, and the annular ligament. The lateral ulnar collateral ligament is the key anatomic structure that prevents posterolateral instability. The radial collateral ligament and the accessory collateral ligament have some contribution to lateral elbow stability. There is consensus that the lateral collateral ligament complex, and not an individual ligament, is important in preventing posterolateral rotatory instability of the elbow. The lateral ulnar collateral ligament acts like a sling for the radial head. It traverses the posterolateral aspect of the radial head. Origin of the lateral ulnar collateral ligament, it arises from the lateral humeral epicondyle. Insertion, it inserts into the crest of the supinator on the proximal ulna. Posterolateral rotatory instability of the elbow occurs with deficiency of the lateral ulnar collateral ligament. It is usually diagnosed with a lateral pivot shift test. The test is done utilizing valgus, supination, and axial load. The lateral ulnar collateral ligament is deep and is slightly distal to the common extensor tendon. Surgical approaches and arthrotomy to the lateral elbow may damage this ligament and may result in posterolateral instability of the elbow.