reconstruction of the anterior cruciate ligament:a comparison between bone-patellar tendon-bone grafts and four-strand hamstring grafts

background :disruption of anterior cruciate ligament (acl) is a common ligamentous injury of the knee. the choice of graft for (acl) reconstruction remains controversial. this prospective, randomized clinical trial aimed to compare clinical results of bone-patellar tendon-bone (bptb) grafts and four-strand semitendinosus-gracilis (st) grafts for acl reconstruction over a 3-year follow-up interval.   methods :seventy-one patients with an average age of 29± 4.5yearswere treated for torn acl between 2008 and 2009. forty-sixpatients underwent reconstruction with bptbautograft, and 41 were treated with stautograft.at the time of final follow-up, 37 patients in patella group and 34 patients in hamstring group were evaluated in terms of return to pre-injury activity level, pain, knee stability, range of motion,ikdc (international knee documentation committee) score and complications.   results : at 36thmonth of follow-up, 34 (92%) and 28 (82%) patients in bptb and st group, respectively had good-to-excellent ikdc score (p > 0.05). theactivity levelswerehigher in bptb group(p> 0.05). at 3rd yearof follow up, the lachman test was graded normal, for 23 (62%) and 11 (32%) patientsin bptb and st group, respectively(p=0.019).regarding the pivot-shift test, 29 (79%) and 15 (44%) patients in patella and hamstring group, respectively had normal test at the latest follow-up (p=0.021).there were no significant differences in terms of thigh circumference difference, effusion, knee range of motion, pain and complications.   conclusion : theresults indicate a trend toward increased graft laxityand pivot-shift grades in patients undergoing reconstruction with hamstring autograft compared with patella tendon. however, the two groups had comparable results in terms of activity level and knee function.