With this condition, the pain is usually worse during and after activity, and the tendon and joint area can become stiffer the following day as swelling impinges on the movement of the tendon. Many patients report stressful situations in their lives in correlation with the beginnings of pain which may contribute to the symptoms.Achilles tendon injuries can be separated into insertional tendinopathy (20%–25% of the injuries), midportion tendinopathy (55%–65%), and proximal musculotendinous junction (9%–25%) injuries, according to the location of pain. Cause
Achilles tendinitis is a common injury, particularly in sports that involve lunging and jumping. It is also a known side effect of fluoroquinolone antibiotics such as ciprofloxacin, as are other types of tendinitis.Swelling in a region of micro-damage or partial tear can be detected visually or by touch. Increased water content and disorganized collagen matrix in tendon lesions may be detected by ultrasonography or magnetic resonance imaging.Achilles tendinitis is thought to have physiological, mechanical, or extrinsic (i.e. footwear or training) causes. Physiologically, the Achilles tendon is subject to poor blood supply through the synovial sheaths that surround it. This lack of blood supply can lead to the degradation of collagen fibers and inflammation. Tightness in the calf muscles has also been known to be involved in the onset of Achilles tendinitis.During the loading phase of the running and walking cycle, the ankle and foot naturally pronate and supinate by approximately 5 degrees.
(Hyperextension is typically achieved by balancing the forefoot on the edge of a step, a thick book, or a barbell weight so that the point of the heel is a couple of inches above the forefoot.) Treatment
Treatment typically involves rest, ice, non-steroidal antiinflammatory agents (NSAIDs), and physical therapy. A heel lift or orthotics may also be helpful, but evidence on both heel lifts and orthotics is limited. Foam rolling may increase range of motion, but there is only weak evidence for the direct treatment of stiffness. Other treatments include:

An eccentric exercise routine designed to strengthen the tendon. Application of a boot or cast. Injections
The evidence to support injection therapies is poor. This includes corticosteroid injections. These can also increase the risk of tendon rupture. Autologous blood injections - results have not been highly encouraging and there is little evidence for their use. Procedures
Tentative evidence supports the use of extracorporeal shockwave therapy. Epidemiology
The prevalence of Achilles tendinitis varies among different ages and groups of people. Achilles tendinitis is most commonly found in individuals aged 30–40 Runners are susceptible, as well as anyone participating in sports,
and men aged 30–39.Risk factors include participating in a sport or activity that involves running, jumping, bounding, and change of speed. Although Achilles tendinitis is mostly likely to occur in runners, it also is more likely in participants in basketball, volleyball, dancing, gymnastics and other athletic activities. Other risk factors include gender, age, improper stretching, and overuse.