often effective. Minimal access surgery using newly reported techniques has also proven successful in a large-scale formal outcome published in 2005. As with injections, the deactivated/ excised muscle's role in leg movement is completely compensated for by surrounding hip muscles. Failure of piriformis syndrome treatment may be secondary to an underlying internal obturator muscle injury. Epidemiology Piriformis syndrome (PS) data is often confused with other conditions due to differences in definitions, survey methods and whether or not occupational groups or general population are surveyed. This causes a lack of group harmony about the diagnosis and treatment of PS, affecting its epidemiology. In a study, 0.33% of 1293 patients with low back pain cited an incident for PS. A separate study showed 6% of 750 patients with the same incidence. About 6–8% of low back pain occurrences were attributed to PS, though other reports concluded about 5–36%. In a survey conducted on the general population, 12.2–27% included a lifetime occurrence of PS, while 2.2–19.5% showed an annual occurrence. However further studies show that the proportion of the sciatica, in terms of PS, is about 0.1% in orthopaedic practice. This is more common in women with a ratio of 3 to 1 and most likely due to the wider quadriceps femoris muscle angle in the os coxae. Between the years of 1991–1994, PS was found to be 75% prevalent in New York, Connecticut, New Jersey, Pennsylvania; 20% in other American urban centers; and 5% in North and South America, Europe, Asia, Africa and Australia. The common ages of occurrence happen between thirty and forty, and are scarcely found in patients younger than twenty; this has been known to affect all lifestyles. Piriformis syndrome is often left undiagnosed and mistaken with other pains due to similar symptoms with back pain, quadriceps pain, lower leg pain, and buttock pain. These symptoms include tenderness, tingling and numbness initiating in low back and buttock area and then radiating down to the thigh and to the leg. A precise test for piriformis syndrome has not yet been developed and thus hard to diagnose this pain. The pain is often initiated by sitting and walking for a longer period. In 2012, 17.2% of low back pain patients developed piriformis syndrome. Piriformis syndrome does not occur in children, and is mostly seen in women of age between thirty and forty. This is due to hormone changes throughout their life,