Approach Considerations
Radial head subluxation is managed by means of manual reduction. Either of the following two reduction methods may be used:
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Supination-flexion technique
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Hyperpronation/forced pronation technique
If one technique fails initially, the other may be attempted.
A 2012 Cochrane review evaluated the literature available for comparison of the two techniques. [17] The reviewers found only four trials, with a total of 379 participants; overall, the methodologic quality was low. Limited evidence from these trials suggested that the hyperpronation method was more effective and less painful.
Supination-Flexion Technique
The supination-flexion technique (see the image below) is the classic method of reducing a subluxated radial head. It has a success rate of 80-92%.
Reduction of subluxated radial head: supination-flexion. Technique begins with supination, followed by full flexion at elbow.
The procedure begins with the patient’s arm in pronation and elbow in 90° of flexion, with pressure applied over the patient’s radial head (see the images below).
Reduction of subluxated radial head: supination-flexion. Technique begins with elbow flexed.
Reduction of subluxated radial head. Shortly after reduction, child resumes using affected arm.
Next, the wrist is firmly supinated, with pressure maintained on the radial head (see the images below).
Reduction of subluxated radial head: supination-flexion. Wrist is supinated with elbow still in 90° of flexion.
Reduction of subluxated radial head: supination-flexion. During supination, pressure is maintained on radial head.
The patient’s elbow is then completely flexed (see the images and videos below). A click is often felt over the radial head (or heard) when the arm has reached full flexion. A palpable or audible click is associated with a high probability of successful reduction.
Reduction of subluxated radial head: supination-flexion. After supination, elbow is fully flexed.
Reduction of subluxated radial head: supination-flexion. With one hand supinating wrist, other thumb feels click as radial head falls into place on full flexion.
Hyperpronation/Forced Pronation Technique
Although the hyperpronation technique (also known as the forced pronation technique) was first described in 1886 by Hutchinson, it has only comparatively recently begun to emerge as a potentially superior means of reduction.
First, the patient’s elbow is held in 90° of flexion. (Some practitioners prefer to have the elbow extended for this technique.) Next, the wrist is firmly hyperpronated (see the image and videos below). As with the supination-flexion technique, a palpable or audible click is associated with a high probability of successful reduction.
Reduction of subluxated radial head: hyperpronation/forced pronation. With one hand placed distally, arm is hyperpronated while other hand holds elbow steady with thumb on radial head.
In a few studies, the hyperpronation technique resulted in fewer failures than supination. [1] It has been suggested that hyperpronation may also be less painful; accordingly, some have advocated hyperpronation as the first-line reduction maneuver. [17, 18, 19]
Using a combination of the two techniques (hyperpronation followed by supination) to ensure reduction has been proposed. Such a combined approach would allow simultaneous assessment the return of proper range of motion.
Postprocedural Care
Once the radial head has been reduced, the child’s pain and apprehension often immediately resolve. The practitioner should leave the patient’s bedside immediately after the procedure and return to reevaluate in 10 minutes. Most children begin to use the affected arm immediately, though some may take as long as 30 minutes to start doing so (see the image below). [20] The time from reduction to normal arm use is increased in younger patients and those whose subluxations have been present for more than 12 hours.
If the first attempt at reduction proves unsuccessful, further attempts can be made (~15 minutes apart); however, alternative diagnoses should be considered after multiple failed attempts. If the child does not begin using the arm normally after such attempts, a radiograph should be obtained to look for fractures or other complications. [21] When multiple reduction attempts prove unsuccessful, a sling or posterior long arm splint may be applied for comfort, and the child can be referred to an orthopedist.
Although a 24-hour sling may be placed on the elbow for comfort, this measure is not necessary for most patients. Occasionally, symptoms may last for several days, and a sling may be worn for longer.
Ultrasonography can be used to evaluate subluxations and determine the success of reduction. Furthermore, it can be used to confirm the healing of the annular ligament after treatment in complex cases. [22]
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Subluxation of radial head occurs after longitudinal traction is placed on pronated extended arm.
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In radial head subluxation, subluxated arm is held semiflexed, adducted, and pronated.
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Alternative diagnoses to radial head subluxation should be sought if point tenderness or any obvious deformity is present.
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Reduction of subluxated radial head: supination-flexion. Technique begins with elbow flexed.
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Reduction of subluxated radial head. Shortly after reduction, child resumes using affected arm.
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Reduction of subluxated radial head: supination-flexion. Wrist is supinated with elbow still in 90° of flexion.
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Reduction of subluxated radial head: supination-flexion. During supination, pressure is maintained on radial head.
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Reduction of subluxated radial head: supination-flexion. After supination, elbow is fully flexed.
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Reduction of subluxated radial head: supination-flexion. With one hand supinating wrist, other thumb feels click as radial head falls into place on full flexion.
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Reduction of subluxated radial head: supination-flexion. Technique begins with supination, followed by full flexion at elbow.
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Reduction of subluxated radial head: hyperpronation/forced pronation. With one hand placed distally, arm is hyperpronated while other hand holds elbow steady with thumb on radial head.
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Shortly after reduction, child resumes using affected arm.
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Reduction of subluxated radial head: supination-flexion. Side view of technique.
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Reduction of subluxated radial head: supination-flexion. Front view of technique.
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Reduction of subluxated radial head: hyperpronation/forced pronation. Side view of technique.
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Reduction of subluxated radial head: hyperpronation/forced pronation. Front view of technique.
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Elbow anatomy with annular ligament.
