Fat Grafting and Retention for Heel Fat Pad Atrophy

Plantar heel pain is the most common problem of the foot. Plantar fasciitis is the leading cause of this pain, accounting for 11-15% of all foot symptoms seeking professional care, and occurs in 10% of the US population. The cause of heel pain can be from bone, soft tissue, nerve, or systemic disease. The second most common cause of heel pain is fat pad atrophy, followed by a combination of both fat pad atrophy and plantar fasciitis. \[1-4\] Fat pad displacement may be seen in the heel as well. Current treatments for plantar fasciitis include stretching and external support with orthotics with the goal of reducing local pressure as well as tissue breakdown.\[5\] However, patient compliance with extrinsic devices is challenging, and they may experience increased friction, irritation and breakdown at a different location on the foot due to thickness of the device in the shoe. Also, the patient must replace the device as soon as it breaks down but the breakdown often goes unnoticed. Failure of conservative management may lead to treatment with steroids or surgical intervention by endoscopic plantar fasciotomy, open fasciotomy or excision of bone spurs. Injection of steroids can instigate or exacerbate pre-existing heel fat pad atrophy. Autologous fat grafting to the heel may reduce plantar pressures, and thus serve as a treatment for heel pain. Autologous fat grafting is currently under investigation for a myriad of clinical scenarios.\[6-19\] Even though autologous fat grafting is not yet an established therapeutic approach for the cited indications, some of the reported results have been intriguing.\[19\] The variable resorption of fat, however, is an important confounding factor in all these studies. Currently the literature reports fat retention rates ranging from 25% to 80%.\[20\] The specific aim of this study is to assess the adipose stem cell characteristics in patients undergoing autologous fat grafting for heel fat pad atrophy and correlate these characteri