Neurogenic arthropathy, also known as Charcot joints, is a rare but severely debilitating disorder of the articular system. Diabetic neuropathy, syringomyelia, trauma, neurosyphilis, and many other diseases can induce this phenomenon. Severe neuropathy and vascular insufficiency lead to a rapidly progressive destruction of the joints with symptoms of swelling and erythema and only mild pain. The diagnosis rests on a detailed patient history, a thorough physical examination, and appropriate imaging studies that determine the underlying cause.
Neurogenic arthropathy, initially named as Charcot neuropathic osteoarthropathy, affects the joints and the skeletal system and possesses a chronic and progressive clinical course    . The pathogenesis stems from a diminished function of the sensory nerves arising due to significant peripheral neuropathy, which may be encountered in various conditions    . By far, the most common etiology is diabetic neuropathy, affecting up to 13% of cases suffering from severe forms of this ailment . Other notable causative factors are syringomyelia, neurosyphilis, trauma to the spinal or peripheral nerves, and several other conditions affecting the nervous system   . Virtually any joint can be affected by neurogenic arthropathy. Some studies have established that neurosyphilis present in the knee, whereas the foot and ankle are mainly targeted in diabetic patients  . The clinical presentation is distinguished by a somewhat rapid onset of erythema and swelling of the joint with minimal or mild accompanying pain, which is one of the reasons why patients present very late to the physician . A limited range of motion and stiffness is frequently observed, particularly in the shoulder joint . In addition to localized joint symptoms, autonomic dysfunction may be simultaneously present with complaints of constipation, urinary retention, erectile dysfunction, and arrhythmias  .
The diagnosis of neurogenic arthropathy rests on the ability of the clinician to raise suspicion toward this disease. In order to gain sufficient evidence, a detailed physical examination and a thorough history are of critical importance. The presence of illnesses that could predispose to this condition, such as diabetes mellitus, must be excluded, while recent trauma is also an important risk factor. Once the course of symptoms, as well as their duration and progression, are assessed, the physical exam should cover a complete neurological workup, including reflex testing and evaluation of the sensory nerves . Neuropathy of any origin can be confirmed by using either the Semmes-Weinstein 5.07/10 g monofilament or simple pinprick testing, whereas the neurometer test might also be employed when possible  . A lower temperature of the affected joint and extremity is readily noted , thus further solidifying the diagnosis of neuropathic origin . To confirm the neurogenic arthropathy, imaging studies need to be performed. Plain radiography, although a very useful method for observing the skeletal system, is of limited benefit due to frequent involvement of soft tissues by local inflammation, which is why magnetic resonance imaging (MRI) is the gold standard    . Scintigraphy, use of Doppler probes, electrophysiology studies, and a skin biopsy are also recommended in the workup of individuals in whom neurogenic arthropathy is suspected .