***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: Nineteen trials providing outcome data for 1597 young to middle-aged adults were included. Many trials were at high risk of bias reflecting inadequate methods of randomization, lack of blinding and incomplete assessment of outcome. Pooled data for primary outcomes, reported in a minority of trials, showed no statistically significant differences between the two graft choices for functional assessment (single leg hop test), return to activity, Tegner and Lysholm scores, and subjective measures of outcome. There were also no differences found between the two interventions for re-rupture or International Knee Documentation Committee scores. There were inadequate long-term results, such as to assess the development of osteoarthritis. All tests (instrumental, Lachman, pivot shift) for static stability consistently showed that PT reconstruction resulted in a more statically stable knee compared with HT reconstruction. Conversely, patients experienced more anterior knee problems, especially with kneeling, after PT reconstruction. PT reconstructions resulted in a statistically significant loss of extension range of motion and a trend towards loss of knee extension strength. HT reconstructions demonstrated a trend towards loss of flexion range of motion and a statistically significant loss of knee flexion strength. The clinical importance of the above range of motion losses is unclear. There is insufficient evidence to draw conclusions on differences between the two grafts for long-term functional outcome. While PT reconstructions are more likely to result in statically stable knees, they are also associated with more anterior knee problems.
Output:

This review included 19 studies reporting the outcomes of ACL reconstruction with patellar tendon versus hamstring tendon grafts in a total of 1597 young to middle-aged adults. Many trials used flawed methods that might have affected their results. The limited data available for functional outcomes including patient-rated assessment did not show whether one graft was better than the other. Similarly, there were no differences found between the two types of graft for re-rupture or in the results of an internationally used knee score. All tests for knee stability favoured patellar tendon grafts. Conversely, people had more anterior knee pain and discomfort with kneeling after patellar tendon reconstruction. After patellar tendon reconstruction, more people had some loss in their ability to straighten out their leg at the knee. In contrast, more people had some loss in their ability to bend their leg at the knee after hamstring tendon reconstruction. It is not clear how important these losses in range of motion of the knee were to the patients themselves. The review concluded that the current evidence was insufficient to recommend which of the two types of graft was better for ACL reconstruction.