Of 50 heel spur samples submitted for pathologic analysis to the Laboratory of Podiatric Pathology at Temple University School of Podiatric Medicine, Philadelphia, Pennsylvania, 10 exhibited normal plantar fascial enthesis characterized by a regular transition of bone to fibrocartilage to fascia (Fig. 1), with fibrocartilaginous fibers running parallel to each other(Fig. 2). In addition, 16 samples demonstrated fiber fragmentation in association with myxoid degeneration characterized by basophilic zones of mucopolysaccharide stained positive with alcian blue (pH 2.5) (Fig. 3).

In two samples, fascial artifacts and fragmentation in association with crystalline material noted in the area before processing was suggestive of previous corticosteroid injections (Fig. 4). Approximately 12 of the 16 samples also demonstrated vascularization of the attached bone marrow (Figs. 5 and 6). Low-power cross-sections of bone re- Figure 1. Normal fascial enthesis exhibiting metaplasia of bone to fibrocartilage to fascia (H&E, × 40). Figure 2. Fibrocartilage interface between bone and fascia (H&E, ×40). moved from the attachment site demonstrated multiple dilated vessels. Hyperemia may be responsible for the reports of “bone contusion” in patients with heel spurs on T2-weighted images. 11 The remaining samples were submitted in sections, preventing adequate pathologic analysis.

In all of the samples reviewed, there was no evidenceof inflammation histologically. A review of the literature and the experience of the authors indicate that credible evidence for the assumption that plantar fasciitis is associated with inflammation is lacking.

On the other hand, there seems to be substantial evidence that this disorder is associated with degenerative changes in the fascia, which may best be classified as a “fasciosis” rather than fasciitis. This redefinition of plantar fasciitis as plantar fasciosis is warranted from an academic perspective in the same way that posterior tibial tenosynovitis has been reclassified as tendinosis and osteoarthritis has been 236 May/June 2003 • Vol 93 • No 3 • Journal of the American Podiatric Medical Association reclassified as osteoarthrosis. Because principles of management are based on a sound understanding of pathology and physiology, common treatment approaches for “heel spur syndrome” or “plantar fasciitis” should be reexamined. For example, the use of serial corticosteroid injections to control “inflammation” in plantar fasciitis should be questioned and reviewed in the absence of documented evidence of inflammation.