Cryptorchidism (over 90% in some studies). Even after orchiopexy, these may also affect sperm maturation and motility at an older age. The most common diagnostic dilemma in otherwise normal boys is distinguishing a retractile testis from a testis that will not descend spontaneously into the scrotum. Retractile testes are more common than truly undescended testes and do not need to be operated on. In normal males, as the cremaster muscle relaxes or contracts, the testis moves lower or higher ("retracts") in the scrotum. This cremasteric reflex is much more active in infant boys than older men. A retractile testis high in
Users' Guides to the Medical Literature guides to the medical literature, IX: a method for grading health care recommendations. JAMA, 274, pp. 1800–1804. Giacomini, M.K. & Cook, D.J., 2000. Users’ Guides to the Medical Literature: XXIII. Qualitative Research in Health Care A. Are the Results of the Study Valid? JAMA, 284(3), pp. 357–362. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.3.357 Giacomini, M.K. & Cook, D.J., 2000. Users’ Guides to the Medical Literature: XXIII. Qualitative Research in Health Care B. What Are the Results and How Do They Help Me Care for My Patients? JAMA, 284(4), pp. 478–482. Available at: http://jama.ama-assn.org/cgi/doi/10.1001/jama.284.4.478. Guyatt, G., Sackett, D. & Cook, D., 1993. Users’ guides