Clinical Insight: Hypertrophic Bone Formation

Tonight I thought we should get back into some good old-fashioned clinical debate and discussion.

The topic I have chosen is post operative Hypertrophic Bone Formation. The reason I selected this topic was because of a challenging case in clinic today at Georgetown; a 52 year old male with long standing history of type 2 diabetes presented for a 6 week follow up on his revisional transmetatarsal amputation. His wounds are healing well and there is no concern for infection, BUT his post op x-rays today show newly forming (and potentially prominent) hypertrophic bone at the distal stump of all 5 metatarsals. This is the second time this particular patient has formed prominent bone within just a few weeks of his metatarsal osteotomies. The revisional procedure, which was just performed as an attempt to address the problematic bone regrowth, utilized power instrumentation and the cuts were made at approximately the mid-shaft of the metatarsal.

So, here is where I need your feedback and discussion so that we can post the results in next week’s column:

	What causes hypertrophic bone formation at the site of an osteotomy or amputation?
	What can potentially be done to prevent the overgrowth?
	Is there a way to predict which patients will likely be affected?
	What patterns have you observed in this area?
	What sites besides metatarsal osteotomies have you experienced this?

The only direct reference to this topic in the literature that I found was an article by Armstrong et al in JBJS Amer Nov 1999. This study references a group of 92 patients with diabetes who underwent a partial ray amputation. It was found that male gender, the use of manual bone-cutting instruments, and metaphyseal level of amputation may be associated with long-term regrowth of bone following isolated partial amputation of a ray.

PLEASE CLICK HERE TO SEND ME AN EMAIL SO THAT I CAN SHARE YOUR INSIGHT IN NEXT WEEK’S COLUMN.

John S. Steinberg, DPM
Editor, PRESENT