Young men and older women are most likely to have shoulder dislocations. Shoulder dislocations are common, accounting for 50% of all joint dislocations throughout the body. The annual incidence of shoulder dislocation is 23.9/100,000, which is higher than previously thought. 48.3% of cases occur in sports, while 37% occur in soccer and basketball. Young men are at highest risk, with 71.8% of men and 46.8% occurring between 15 and 29 years of age. Therefore, strengthening motor protection against falls at home in the elderly is the main measure to prevent shoulder dislocation. Other studies have found that 90-98% are anterior dislocations. Posterior dislocation is rare, so it is often missed. The chance of recurrence is 30% for people who do not like sports, and 82% for athletes or people who like sports. Therefore, some doctors recommend that young people have surgery after their first shoulder dislocation, rather than waiting until a habitual dislocation has developed before undergoing surgery. One study found that the incidence of re-dislocation after manual repositioning of the shoulder joint was 94% with conservative treatment, while the incidence of re-dislocation with arthroscopic surgery was 4%.