This has subsequently been shown by an increase in proinflammatory phenotypes of monocytes in those with active Charcot foot when compared with diabetic control subjects ( 3). It has been suggested that this results in continual production of proinflammatory cytokines, RANKL, NF-κβ, and osteoclasts, which in turn leads to continuing local osteolysis ( 1). In the person who develops an acute Charcot foot, however, the loss of pain sensation allows for uninterrupted ambulation, with repetitive trauma. The fracture will also be associated with pain, and this leads to splinting of the bone, and the rise in proinflammatory cytokines is usually relatively short-lived. This “decoy receptor” acts as an effective antagonist of RANKL ( 2). At the same time, NF-κβ stimulates the production of the glycopeptide osteoprotegerin (OPG) from osteoblasts.

RANKL triggers the synthesis of the nuclear transcription factor nuclear factor-κβ (NF-κβ), and this in turn stimulates the maturation of osteoclasts from osteoclast precursor cells. When a bone is fractured, the release of proinflammatory cytokines including tumor necrosis factor-α and interleukin-1β leads to increased expression of the polypeptide receptor activator of nuclear factor-κB ligand (RANKL) from any of a number of local cell types. Pain or discomfort may be a feature of this disorder at the active (acute) stage, but the level of pain may be significantly diminished when compared with individuals with normal sensation and equivalent degrees of injury. 1), although the condition appears in other joints and with other presentations. The hallmark deformity associated with this condition is midfoot collapse, described as a “rocker-bottom” foot ( Fig. The interaction of several component factors (diabetes, sensory-motor neuropathy, autonomic neuropathy, trauma, and metabolic abnormalities of bone) results in an acute localized inflammatory condition that may lead to varying degrees and patterns of bone destruction, subluxation, dislocation, and deformity. The Charcot foot has been documented to occur as a consequence of various peripheral neuropathies however, diabetic neuropathy has become the most common etiology. Charcot neuropathic osteoarthropathy (CN), commonly referred to as the Charcot foot, is a condition affecting the bones, joints, and soft tissues of the foot and ankle, characterized by inflammation in the earliest phase.

Rocker bottom foot radiology