Negative signs include a lack of obvious deformities, erythema, signs of inflammation, or limitation of movement. Direct pressure between the metatarsal heads will replicate the symptoms, as will compression of the forefoot between the finger and thumb so as to compress the transverse arch of the foot. This is referred to as Mulder’s Sign. There are other causes of pain in the forefoot that often lead to miscategorization as neuroma, such as capsulitis, which is an inflammation of ligaments that surround two bones at the level of the joint. If the ligaments that attach the phalanx (bone of the toe) to the metatarsal bone are impacted, the resulting inflammation may put pressure on an otherwise healthy nerve and produce neuroma-type symptoms. Additionally, an intermetatarsal bursitis between the third and fourth metatarsal bones will also give neuroma-type symptoms because it too puts pressure on the nerve. Freiberg disease, which is an osteochondritis of the metatarsal head, causes pain on weight-bearing or compression. Other conditions that could be clinically confused with a neuroma include stress fractures/reactions and plantar plate disruption. Histopathology Microscopically, the affected nerve is markedly distorted, with extensive concentric perineural fibrosis. The arterioles are thickened and occlusion by thrombi are occasionally present. Imaging Though a neuroma is a soft-tissue abnormality and will not be visualized by standard radiographs, the first step in the assessment of forefoot pain is an X-ray to detect the presence of arthritis and exclude stress fractures/reactions and focal bone lesions, which may mimic the symptoms of a neuroma. Ultrasound (sonography) accurately demonstrates thickening of the interdigital nerve within the web space of greater than 3mm, diagnostic of a<unk> . This typically occurs at the level of the intermetatarsal ligament. Frequently, intermetatarsal bursitis coexists with the diagnosis. MRI can distinguish conditions that mimic the symptoms of<unk> , but when more than one abnormality exists, ultrasound has the added advantage of determining the precise source of the patient’s pain by applying direct pressure with the probe. Ultrasound may also be used to guide treatment such as cortisone injections into the webspace, as well as alcohol ablation of the nerve.
Morton's neuroma
Bunion
Traumatic neuroma
Plantar fibromatosis
Volkmann's contracture
Dupuytren's contracture
Heel pad syndrome
Median rhomboid glossitis