The most common cause of cubitus valgus is unreduced or poorly reduced supracondylar fractures of the humerus and distal humeral fractures in children. Untimely or poorly reduced medial and lateral condylar fractures of the humerus in children, premature closure of the lateral condylar epiphysis or avascular necrosis, as well as unreduced or poorly reduced elbow dislocations can all lead to cubitus valgus.

bubble_chart Pathogenesis

1. Unreduced or poorly reduced humerus supracondylar fractures and distal humerus fractures in children are the most common causes of cubitus valgus deformity. The reason is the imbalance in the growth of the medial and lateral sides of the distal humerus.

2. Untimely or poorly reduced medial and lateral hip bone fractures in children, premature closure of the lateral hip bone epiphysis, or ischemic necrosis can lead to cubitus valgus; medial hip bone fractures causing cubitus valgus are due to excessive growth of the medial condyle.

3. Unreduced or poorly reduced elbow dislocation.

4. After radial head resection: The cause of cubitus valgus is the loss of the important mechanical blocking effect of the proximal radius after radial head resection, leading to abnormal biomechanics of the elbow joint and forearm.

bubble_chart Clinical Manifestations

When the elbow joint is extended, the valgus angle of the elbow increases and can exceed 30°; there is generally no significant limitation in elbow joint movement. In the advanced stage, injury to the articular surface of the elbow joint can cause pain. For patients with severe valgus, due to the ulnar nerve being under high-tension traction or frequent friction caused by post-traumatic adhesion of the ulnar nerve, delayed ulnar neuritis may occur, leading to manifestations of ulnar nerve injury.

bubble_chart Treatment Measures

Generally, cubitus valgus without elbow joint dysfunction or pain symptoms does not require treatment.

1. Conservative treatment: Suitable for patients with early-stage elbow osteoarthritis, mild clinical symptoms, and no significant elbow joint dysfunction. Pain is the most common symptom and can be managed with physical therapies such as physiotherapy and tuina, or medications like aspirin.

① Severe cubitus valgus deformity that has remained stable for over 2 years.

② Obvious symptoms of joint pain and weakness that significantly impair elbow function.

③ Presence of traumatic arthritis.

④ Associated with delayed ulnar neuritis. The surgical approach involves supracondylar osteotomy correction and ulnar nerve transposition. The primary goals of osteotomy correction are to rectify the deformity, stabilize the joint, alleviate pain, correct uneven joint stress distribution, and prevent further joint degeneration.