***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background Concomitant injuries to secondary structures have been proposed as a major cause of failure of anterior cruciate ligament reconstruction . Purpose Our purpose was to determine the relationship between meniscal status at the time of anterior cruciate ligament reconstruction and ultimate long-term function and stability . Study Design Prospect i ve cohort study . Methods We prospect ively studied 63 patients for an average of 10.4 years after arthroscopically assisted bone-patellar tendon-bone anterior cruciate reconstruction . All surgeries were performed between 1988 and 1991 ; concomitant meniscal surgery was performed if necessary . Subjects were divided into subgroups relative to the integrity of their menisci at the end of the reconstruction procedure ( intact meniscus , partial meniscectomy , complete meniscectomy ) . Results Patients who had undergone any degree of meniscal resection reported significantly more subjective complaints and activity limitations than those with intact menisci . Subjective International Knee Documentation Committee and Lysholm scores were lower in the meniscectomy subgroups than in the meniscus-intact group . Objective testing revealed a significantly lower ability to perform the single-legged hop in the meniscectomy subgroups . Ligament stability based on instrumented laxity measurements was not significantly different between the subgroups . Radiographic abnormalities were also more common in the subgroups that had undergone meniscectomy . Conclusions The menisci should be repaired if at all possible , especially in the setting of anterior cruciate ligament reconstruction , for optimal functional outcome and patient satisfaction PURPOSE To evaluate the clinical results of anterior cruciate ligament ( ACL ) reconstruction in patients with ACL-deficient knee in 2 similar groups of patients . TYPE OF STUDY A prospect i ve r and omized comparison of patellar tendon ( PT ) versus semitendinosus and gracilis tendon ( STG ) autografts for ACL reconstruction . METHODS Between 1994 and 1996 , 85 consecutive male patients with chronic ACL-deficient knees underwent arthroscopically assisted reconstruction with either autologous PT or double-loop STG ( 4-str and ) graft . PT grafts were used in patients with even-numbered birth date s and STG grafts for those with odd-numbered birth date s. Preoperatively , no significant differences between the 2 groups were noted with respect to age , level of activity , and degree of laxity ( chi-square analysis ) . A st and ardized rehabilitation program was used for both groups postoperatively that included immediate active extension and early weight bearing and gradual flexion . Return to sports was permitted 8 months postoperatively . Assessment of the patients was carried out using a question naire , clinical assessment , Lysholm knee scores , the International Knee Documentation Committee scale , and radiological examination . RESULTS At a mean follow-up of 81 months , there was no significant difference between the 2 groups with respect to subjective complaints ( recurrent giving way , functional level ) or objective laxity evaluation , including KT-1000 measurement or return to sports . Loss of extension of < or = 5 degrees was greater in the PT group ( 12 patients , 30 % ) than in the STG group ( 8 patients , 17 % ) . There was loss of flexion of < or = 15 degrees in 5 patients ( 12 % ) in the PT group and 1 patient ( 2.2 % ) in the STG group . Anterior knee pain was recorded in 10 patients ( 24 % ) in the PT group and 3 patients ( 5 % ) in the STG group . The Lysholm knee score was 91.6 and 92.7 for the PT and STG groups , respectively , and the Tegner activity score decreased from 8.9 preoperatively for both groups to 7.9 for the PT group and 7.8 for the STG group . CONCLUSION In this study , the 2 groups had comparable results in terms of patient satisfaction , activity level , and knee function . Our study showed that patellofemoral problems and loss of knee motion are more frequent in patients with PT grafts than in those with STG grafts . LEVEL OF EVIDENCE Level I , R and omized Controlled Trial Background There are still controversies about graft selection for  primary anterior cruciate ligament reconstruction .  Prospect i ve r and omized long-term studies are needed to determine the differences between the material s. Hypothesis Five years after  anterior cruciate ligament reconstruction  , there is a difference between hamstring and patellar tendon grafts in development of degenerative knee joint disease . Study Design R and omized controlled trial ; Level of evidence , 1 . Methods From June 1999 to March 2000 , 64 patients were included in this prospect i ve study . A single surgeon performed primary arthroscopically assisted anterior cruciate ligament reconstruction in an alternating sequence . In 32 patients ,  anterior cruciate ligament reconstruction was performed with hamstring tendon autograft , whereas in the other 32 patients ,  anterior cruciate ligament reconstruction was performed with patellar tendon autograft . Results At the 5-year follow-up , no statistically significant differences were seen with respect to the Lysholm score , clinical and KT-2000 arthrometer laxity testing , anterior knee pain , single-legged hop test , or International Knee Documentation Committee classification results ; 23 patients ( 82 % ) in the hamstring tendon group and 23 patients ( 88 % ) in the patellar tendon group returned to their preinjury activity levels . Graft rupture occurred in 2 patients from the hamstring tendon group ( 7 % ) and in 2 patients from the patellar tendon group ( 8 % ) . Grade B abnormal radiographic findings were seen in 50 % ( 13/26 ) of patients in the patellar tendon group and in 17 % ( 5/28 ) of patients in the hamstring tendon group ( P = . 012 ) . Conclusion Both hamstring and patellar tendon grafts provided good subjective outcomes and objective stability at 5 years . No significant differences in the rate of graft failure were identified . Patients with patellar tendon grafts had a greater prevalence of osteoarthritis at 5 years after surgery Background : The purpose of this study was to further delineate the outcome of arthroscopically assisted anterior cruciate ligament reconstruction in 125 patients who had previously been followed for two to five years . One of the original 125 patients was excluded from the present study because of insufficient follow-up , and an additional group of 101 patients was added . All 225 patients in the present study were followed for a minimum of six years . Methods : Patients were r and omly assigned to reconstruction with a double-str and ed semitendinosus-gracilis graft with use of a two‐incision technique ( group I ) , reconstruction with a patellar ligament graft with use of a two‐incision technique ( group II ) , or reconstruction with a patellar ligament graft with use of a single‐incision endoscopic technique ( group III ) . The groups were compared with regard to the rate of graft failure , the amount of instability , knee strength , radiographic signs of degenerative changes , and functional outcome . Results : There was no significant difference among the three groups with regard to the rate of graft failure , the amount of knee instability , or the functional outcome . A normal or nearly normal functional outcome was recorded for 208 ( 92 % ) of the 225 patients . There were significant differences among the groups with regard to quadriceps muscle-strength deficits : group I had fewer patients with deficits than group III , and groups I and III both had fewer patients with deficits than group II ( p = 0.04 ) . There also were significant differences among the groups with regard to hamstring muscle-strength deficits : group III had fewer patients with deficits than group II , and group II had fewer patients with deficits than group I ( p < 0.01 ) . Twelve knees ( 16 % ) in group I , six knees ( 8 % ) in group II , and eight knees ( 11 % ) in group III showed radiographic evidence of progressive degenerative changes , but the differences among the three groups were not significant . Conclusion : Although 11.6 % of the 225 knees had radiographic evidence of degenerative arthritis at a minimum of six years after arthroscopically assisted reconstruction of the anterior cruciate ligament , the choice of graft and the technique of reconstruction did not seem to affect the rate of development of these changes 
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However , the patient-reported outcomes in these studies were not different .
Radiographic evidence of osteoarthritis was inconsistent between autograft choices .
Conclusion This level II systematic review demonstrates no difference in major clinical results between graft types with the exception of increased anterior knee and kneeling pain .
There exists a potential for increased incidence of osteoarthritis in the patellar tendon group but increased sample size is required .