Nursemaids elbow

Pathophysiology: In young children, the annular ligament that encircles the radial head is loosely attached and can partially slip over the radial head when the arm is pulled while extended and pronated. This results in subluxation rather than true dislocation. Common mechanisms include a caregiver swinging a child by the arms, lifting them by one hand, or the child falling while being held by the hand.

Clinical presentation: The child typically presents with acute onset of arm pain and refusal to use the affected limb (pseudoparalysis). The arm is held in slight flexion and pronation close to the body. There is no swelling, deformity, or bruising, distinguishing it from fracture. Point tenderness is minimal, and the child cries with attempted supination or flexion.

Diagnosis: This is a clinical diagnosis based on history and exam; radiographs are typically normal and not required unless there is concern for fracture, deformity, or if the reduction maneuver fails, in which case imaging should be pursued to rule out other pathology (e.g., supracondylar fracture).

Management: Reduction is performed using either the hyperpronation technique or supination-flexion technique. The examiner supports the elbow with a thumb over the radial head while pronating or supinating and flexing the forearm; a palpable/audible click often signifies successful reduction. Children typically resume normal arm use within 5-15 minutes post-reduction. Recurrence is common, and parents should be educated to avoid pulling on the child's arms.

Key associations: Peak incidence in children 1-4 years old; slightly more common in girls; left arm more commonly affected (may relate to right-handed caregivers pulling). Recurrent subluxations may loosen the annular ligament further, and most children outgrow susceptibility by age 5 as the ligament strengthens and the radial head enlarges.