Medial epicondyle fractures of the humerus

　　Fractures of the medial epicondyle of the humerus are often caused by falling to the ground or throwing sports injuries. When the elbow joint is extended and falls, the hand supports the ground, the upper limb is in an abduction position, the external rotation stress causes the elbow joint to rotate externally, while the flexor muscles of the forearm contract abruptly, tearing off the medial epicondyle. The medial epicondyle is a late-closed epiphysis, and the growth plate itself is a potential weakness before it closes, so it can cause epiphyseal separation, traction downward and forward, and rotational displacement. At the same time, the medial interosseous space of the elbow joint is temporarily opened, or posterior lateral dislocation of the elbow joint occurs, and the torn-off medial epicondyle (epiphysis) is trapped within the joint. According to the severity of the injury, it can be divided into 4 degrees.

　　Ⅰ° injury: Only fracture or ossification separation, with very little displacement.

　　Ⅱ° injury: The bone fragments have downward displacement and forward rotational displacement, which can reach the joint level.

　　Ⅲ° injury: Fracture fragments are embedded in the joint, and there is also partial dislocation of the elbow joint.

　　Ⅳ° injury: Posterior or posterolateral dislocation of the elbow joint, with bone fragments trapped in the joint.

　　This disease is caused by traumatic factors and is prone to be complicated with other injuries, including radial head, neck, and olecranon fractures, and the most common complication of this disease is varus, sometimes accompanied by elbow joint dislocation. Pay attention to whether the ulnar nerve is injured.

　　Many scholars have proposed different views on the mechanism of varus, and the general view is: varus is caused by the compression and collapse of the medial cortex of the distal fracture end, poor reduction or maintenance of reduction, and gravity-induced medial displacement and ulnar tilt. It is not related to the growth rate of ossification, and the rotational displacement of the distal fracture end leads to varus. This is because the rotational support points are mostly located in the wider and thicker lateral condyle, the medial condyle loses support, and the body's gravity and the force of muscle traction cause the inside tilt.

　　When a avulsion fracture of the humeral epicondyle occurs, the lateral tissues of the elbow joint, such as the collateral ligament, joint capsule, epicondyle, and ulnar nerve, can be damaged. The inside of the elbow joint is swollen and painful. Subcutaneous ecchymosis can be seen locally. Tenderness is limited to the inside of the elbow. Sometimes, the sensation of bone friction can be felt. The extension and rotation function of the elbow joint is limited.

　　This disease belongs to traumatic diseases, attention should be paid to safety in daily life, there are no other effective preventive measures, and especially attention should be paid to the fact that this disease is prone to develop medial varus. Therefore, for patients with this disease, in addition to active treatment, attention should also be paid to prevent the occurrence of varus, and the key points of prevention are as follows:

　　1. Good fracture reduction.

　　2. Reasonable fixation.

　　3. Correct X-ray evaluation.

　　The diagnosis of humeral epicondyle fractures can be confirmed by X-ray examination. In addition to the anteroposterior and lateral X-ray films, special positions should also be taken according to the condition of the injury, such as the open position (upper cervical injury), dynamic lateral position (cervical vertebrae), axial position (navicular bone, calcaneus, etc.), and tangential position (patella) and so on. For complex pelvic fractures or those suspected of having intraspinal fractures, it is advisable to take tomography or CT examination according to circumstances.

　　Fractured patients of the humeral epicondyle should avoid eating sour and spicy, dry and hot, and greasy foods in the early stage. It is especially forbidden to take greasy and nourishing foods such as bone soup, fatty chicken, and braised fish too early, otherwise, the blood stasis will accumulate and be difficult to disperse, which will inevitably delay the course of the disease, slow down the growth of callus, and affect the recovery of joint function in the future. In addition, there are the following dietary precautions:

　　1. Avoid eating too many meat bones

　　Some people think that eating more meat bones after fractures can promote early healing. In fact, this is not the case. Modern medicine has proven through multiple practices that eating more meat bones after fractures not only cannot promote early healing but may also delay the healing time of fractures. The reason for this is that the regeneration of bone after injury mainly relies on the function of the periosteum and bone marrow. The periosteum and bone marrow can only better exert their function under the condition of increasing collagen. The main components of meat bones are phosphorus and calcium. If a large amount is ingested after fracture, it will promote the increase of inorganic components in the bone, resulting in a disorder of the proportion of organic components in the bone. Therefore, it will have a hindering effect on the early healing of fractures. However, fresh meat bone soup tastes delicious and has a stimulating effect on appetite, so eating a small amount is harmless.

　　2. Avoid fad diets

　　Fracture patients often have local edema, congestion, bleeding, muscle tissue damage, and other conditions. The body itself has resistance and repair capabilities for these. While the body repairs tissues, the growth of long bones, the formation of callus, and the removal of blood stasis and swelling rely on various nutrients. Therefore, it can be known that the key to the smooth healing of fractures is nutrition.

　　3. Avoid indigestible foods

　　Due to the restricted activity of fracture patients caused by the fixation of plaster or splint, and the swelling and pain at the injury site, as well as mental anxiety, the appetite is often poor, and constipation may occur from time to time.

　　4. Avoid overeating sugar

　　After taking in a large amount of sugar, glucose metabolism will increase rapidly, thereby producing intermediate metabolites such as pyruvate and lactic acid, causing the body to be in an acidic poisoning state. At this time, alkaline calcium, magnesium, and sodium ions will immediately be mobilized to participate in neutralization to prevent the blood from becoming acidic. Such a large consumption of calcium is unfavorable for the recovery of fracture patients. At the same time, too much sugar will also reduce the content of vitamin B1 in the body, because vitamin B1 is an essential substance for the conversion of sugar into energy in the body. Vitamin B1 deficiency greatly reduces the activity of nerves and muscles and also affects the recovery of function. Therefore, fracture patients should avoid eating too much sugar.

　　5. Avoid long-term use of Sanqi tablets

　　During the early stage of fractures, local internal bleeding occurs, blood stasis, swelling, and pain. At this time, taking Sanqi tablets can contract the local blood vessels, shorten the coagulation time, increase the thrombin, which is very appropriate. However, after one week of fracture reduction, bleeding has stopped, and the damaged tissue begins to repair. Since the repair requires a large amount of blood supply, if Sanqi tablets are continued to be taken, the local blood vessels are in a state of contraction, and blood circulation is not smooth, which is unfavorable for fracture healing.

　　6. It is forbidden to drink fruit juice during fractures

　　The raw material of fruit juice is made by mixing sugar water, flavoring essence, pigments, and other ingredients. It does not contain the vitamins and minerals needed by the human body. Because it contains a lot of sugar, it presents a physiological acidic state in the body after drinking.

　　Non-displaced fracture of the medial epicondyle of the humerus does not require reduction and can be fixed with a long arm splint or an ultra-articular splint for 3 to 4 weeks. After the splint or splint is removed, functional exercise should be performed. Fractures of grade II and above should be first reduced by hand, and surgery should be performed if it fails.

　　1. Manipulative Reduction

　　Local anesthesia or brachial plexus anesthesia, for Grade II fractures, the elbow joint should be flexed to 90°, the forearm pronated, so that the forearm flexors relax, the operator uses the thumb to push away the hematoma, and push the fracture fragments from below upwards to reduce them. If it is Grade III fracture, the assistant can first abduct and supinate the forearm, so that the elbow joint is externally rotated, so that the medial space is opened, then extend the wrist and fingers, and then extend the elbow joint further, which is called the 'three extensions' reduction method, then quickly pull the forearm flexors tight, pull the fracture fragments out of the joint space, and then treat them as Grade II fractures. Another technique is that one assistant fixes the lower end of the upper arm, and the other assistant rotates the forearm极度 pronated, the operator uses the thumb to push and press from the anterior superior direction to the posterior inferior direction at the humeral trochlea until the fracture block is pushed out. For those with elbow joint dislocation, that is, Grade IV fracture, during the reduction of the elbow joint, the dislocated medial epicondyle fracture often can be reduced with it. If the elbow joint has been reduced but the medial epicondyle has not been reduced, it can be treated as Grade II fracture.

　　2. Percutaneous Prying Reduction and Fixation

　　Except for Grade I fractures, which generally will not dislocate due to no tearing of the periosteum and the attachment of the flexor tendons, other types of fractures may become unstable after reduction and can cause redisplacement. In this case, closed needle pinning fixation can be used, and if the fracture fragments have rotation and are difficult to reduce by manipulation, percutaneous needle prying reduction can be used, and 1 to 2 Kirschner wires can be used for internal fixation. After the operation, the cast brace or a small splint beyond the joint can be used for external fixation for 3 to 4 weeks.

　　3. Open Reduction

　　Applicable to fractures with obvious separation, or when the fracture fragments are difficult to remove from the joint cavity by manipulation, rotational displacement manipulation has not corrected, and there is concurrent ulnar nerve injury. The operation should take an incision on the medial side of the elbow to protect the ulnar nerve, expose the fracture end, remove hematomas or granulation tissue, identify the direction of the fracture surface, flex the elbow to 90°, pronate the forearm, use a bandage clip to hold the fracture fragment in place for reduction, and use two fine Kirschner wires for cross-fixation. Adults with larger fracture fragments can be fixed with cancellous bone screws. Smaller ones can also be excised, and the attachment of the flexor tendons can be sutured onto the nearby fascia. Children can also use silk thread to suture and fix the fracture fragments. For ulnar nerve contusions, examination should be given; if severe, the ulnar nerve advancement surgery can be performed simultaneously. After the operation, the cast brace should be used for fixation for 4 to 5 weeks, and then the cast brace is removed and the steel pins are removed before functional exercise.