Multiple hereditary exostosis is an uncommon tumorous condition and is capable of causing significant functional limitations. I have previously posted on MHE. While multiple hereditary exostosis in the fingers can cause deformity and limitations of finger flexion (I need to post on this topic), we worry more about the forearm. The problem is that if the two bones of the forearm don’t grow at the same rate, the natural rotation of the forearm may be lost.
However, when the bones don’t grow at the same rate, the best techniques for surgical correction in multiple hereditary exostosis is not clear. Multiple techniques have been described including lengthening the short ulna, correcting angulation of the radius, or ‘detethering’ (separation) of the radius and ulna growth. There is no question that these techniques each have a role and make conceptual sense. And all may allow the x-rays to look better. But none have shown to clearly improve motion in patients with multiple hereditary exostosis.
And, to make things more confusing- even patients with dramatic findings on x-ray can do very well functionally. The case below in a 12 year old with multiple hereditary exostosis proves this point. She has no pain, great motion, and no interest in surgery. Time will determine if her outstanding function continues.
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| Multiple hereditary exostosis. Note the radial head dislocation on the left. |
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| Multiple hereditary exostosis. Great forearm supination. |
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Multiple hereditary exostosis. Very good but not perfect forearm rotation on both sides.
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Multiple hereditary exostosis. Right radial head is out of position.
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Multiple hereditary exostosis. Right radial head is dislocated.
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| Left elbow with radial head dislocation (with great motion and function). In multiple hereditary exostosis. |
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| Right elbow with radial head dislocation although not as notable as the left (with great motion and function). In multiple hereditary exostosis. |
