4 mm, the lateral fascicle at 2 mm, and the medial less than a millimeter thick. In theory, plantar fasciitis becomes more likely as the plantar fascia's thickness at the calcaneal insertion increases. A thickness of more than 4.5 mm ultrasound and 4 mm on MRI are useful for diagnosis. Other imaging findings, such as thickening of the plantar aponeurosis, are nonspecific and have limited usefulness in diagnosing plantar fasciitis. Three-phase bone scan is a sensitive modality to detect active plantar fasciitis. Furthermore, a 3-phase bone scan can be used to monitor response to therapy, as demonstrated by decreased uptake after corticosteroid injections. Differential diagnosis The differential diagnosis for heel pain is extensive and includes pathological entities including, but not limited to, the following: calcaneal stress fracture, septic arthritis, calcaneal bursitis, osteoarthritis, spinal stenosis involving the nerve roots of lumbar spinal nerve 5 (L5) or sacral spinal nerve 1 (S1), calcaneal fat pad syndrome, metastasized cancers from elsewhere in the body, hypothyroidism, gout, seronegative spondyloparthopathies such as reactive arthritis, ankylosing spondylitis, or rheumatoid arthritis (more likely if pain is present in both heels), plantar fascia rupture, and compression neuropathies such as tarsal tunnel syndrome or impingement of the medial calcaneal nerve. A determination about a diagnosis of plantar fasciitis can usually be made based on a person's medical history and physical examination. When a physician suspects a fracture, infection, or some other serious underlying condition, they may order an X-ray to investigate. X-rays are unnecessary to screen for plantar fasciitis for people who stand or walk a lot at work unless imaging is otherwise indicated. Treatment Non-surgical About 90% of plantar fasciitis cases improve within six months with conservative treatment, and within a year regardless of treatment. The recommended first treatment is a 4-6 week course which combines three elements: daily stretching, daily foot taping (using a special tape around the foot for supporting the arch) and individually tailored education on choosing footwear and other ways of managing the condition. If plantar fasciitis fails to respond to conservative treatment for at least three months, then extracorporeal shockwave therapy (ESWT) may be considered. Evidence from meta-analyses suggests significant pain relief lasts up to one year after the procedure. However, debate about the therapy's efficacy has persisted. ESWT is performed with or without anesthesia though studies suggest giving anesthesia diminishes the procedure's effectiveness. Complications from ESWT are rare and typically benign when