: Introduction: Soft tissue injuries, particularly ligaments and tendons, are the most common injuries in sports, account for more than 50% of all injuries and often require orthopedic surgery. According to data in the general population, the incidence rate of anterior cruciate ligament (ACL) injury was 1:3500. The treatment option of ACL injury cases include physical exercise and reconstruction surgery. Graft options for the ACL reconstruction include:autograft and allograft. One of the most popular autograft is hamstring. The use of hamstrings in ACL reconstruction still arguing among the expert. The choice of autograft that can be chosen as a new alternative is the peroneus longus tendon. Currently, there is very few biomechanical study on peroneus longus strength as an alternative choice of autograft in ACL reconstruction. The study to determine the tensile strength of the peroneus longus tendon was conducted by the researcher as a preliminary study that could bring new perspective for future studies. Materials and methods: This is an experimental research. Six human cadaveric specimens as research material. Each cadaver was treated by taking hamstring and peroneus from both lower limbs. The hamstring and peroneal tendons were then measured by applying the Hydraulic Servo Pulser tensile test apparatus. Data on tensile strength comparison between peroneal tendon and hamstring were analyzed by descriptive and inferential statistics. Result: From the measurement results, it is known that hamstring has lower average tensile strength value compared to peroneus without significant difference (p > 0.05). Conclusion: The tensile strength of the peroneus longus tendon, which is similar to that of hamstring, gives information that both have the same biomechanic properties. Peroneus longus should not be used as a first option in ACL reconstruction, but may be used as an alternative donor in cases involving multiple instability that require more tendon donors in the reconstruction. Highlights:

Background: The Knee injury and Osteoarthritis Outcome Score (KOOS) is a useful diagnostic tool to assess knee ligament injury and osteoarthritis, but no validated Indonesian version of the KOOS was available. Methods: We used the forward-backward translation protocol to develop the Indonesian version of the KOOS. The translated questionnaire was administered twice to 51 subjects diagnosed with a knee ligament injury and osteoarthritis. Validity of the questionnaire was assessed by analyzing the correlation between the score of each subscale and the overall score of the 36-Item Short Form Health Survey (SF-36) using the Pearson correlation coefficient. Reliability was measured by evaluating internal consistency (Cronbach α) and test-retest reliability (intraclass correlation coefficient). Results: For construct validity, moderate Pearson correlation coefficients were found between the KOOS subscales and the SF-36. Cronbach α was 0.84 to 0.97 for all subscales, indicating adequate internal consistency. The test-retest reliability was excellent, with intraclass correlation coefficients ranging from 0.91 to 0.99 for all subscales. No significant differences were found in the KOOS subscale responses between the first administration of the questionnaire and the second administration within 21 days. Conclusion: The Indonesian version of the KOOS was determined to be valid and reliable and is therefore an objective instrument for evaluating knee ligament injury and knee osteoarthritis in the Indonesian population.

Background: The Kujala score is a useful diagnostic tool to evaluate patellofemoral pain syndrome (PFPS). However, no validated Indonesian version of the Kujala score has been available. Purpose: To develop and validate an Indonesian version of the Kujala score. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: This was a cross-sectional study to develop an Indonesian version of the Kujala score by using a forward-backward translation protocol. The resulting questionnaire was given to 51 patients diagnosed with PFPS. The validity of the questionnaire was evaluated by correlating the final score with the Indonesian version of the 36-Item Short Form Health Survey (SF-36). Reliability was measured by evaluating the internal consistency (Cronbach alpha) and test-retest reliability (intraclass correlation coefficient [ICC]). Results: The Indonesian version of the Kujala score had a positive correlation with the physical components of the SF-36. The internal consistency was fairly high (α = .74), and the test-retest reliability was excellent (ICC, 0.996). Conclusion: The Indonesian version of the Kujala score was proven to be a valid and reliable tool to diagnose PFPS. Future epidemiological studies could implement this score to find the prevalence of PFPS in Indonesia. Further, ensuing studies could explore the application of this scoring system in posttreatment and postoperative settings.

Anterior Cruciate Ligament (ACL) is the most common ligament injury during sports activities that was treated with ACL reconstruction. Nowadays, peroneus longus is used in ACL reconstruction. However, it is difficult to predict the peroneus longus graft diameter for ACL reconstruction. Thus, preoperative measurements are very important to predict peroneus longus autograft for ACL reconstruction. A cohort retrospective study was conducted using consecutive sampling method from February 2016 until October 2017 in our center. We recorded patients' characteristics include gender, age, body weight, height, and Body Mass Index (BMI) preoperatively. We measured peroneus longus graft diameter intraoperatively, and analysed data using Spearman correlation. Thirty-nine patients met inclusion criteria. There were 28 males and 11 females in the peroneus group. From the patients' mean characteristics, age was 25.10 ± 9.16, body weight 71.23 ± 14.17, height 169.13 ± 8.81, and BMI 20.96 ± 3.44. Intraoperative peroneus longus diameter measurement was 8.56 ± 0.82. Spearman correlation showed significant correlation between intraoperative peroneus longus diameter with patient's height, body weight, and BMI with p < 0.05. Patients' characteristics including gender, height, weight, and BMI in preoperative measurements can predict peoneus longus graft diameter intraoperatively.