[Comparison of early effectiveness of arthroscopic suture bridge technique and conventional double tunnel suture technique in treatment of avulsion fracture of posterior cruciate ligament insertion].

OBJECTIVE: To compare the early effectiveness of arthroscopic suture bridge technique and conventional double tunnel suture technique in the treatment of avulsion fracture of posterior cruciate ligament (PCL) insertion. METHODS: Between June 2013 and December 2018, 62 patients with tibial avulsion fracture of PCL insertion that met the criteria were selected and randomly divided into trial group (using arthroscopic suture bridge technique) and control group (using conventional double tunnel suture technique), 31 cases in each group. There was no significant difference in gender, age, injured side, cause of injury, time from injury to operation, Meyers & McKeever classification, Kellgren-Lawrence classification, and preoperative knee range of motion, difference of posterior relaxation of bilateral knee joints, International Knee Documentation Committee (IKDC) score, and Lysholm score between the two groups ( P>0.05). The operation time and IKDC score, Lysholm score, knee range of motion, the difference of posterior relaxation of bilateral knee joints (measured by KT-2000 under knee flexion of 90° and 30 lbs) were recorded and compared between the two groups before operation and at 3 and 12 months after operation. RESULTS: Both groups successfully completed the operation, and the operation time of the trial group and the control group were (61.81±6.83) minutes and (80.42±4.22) minutes respectively, showing significant difference between the two groups ( t=12.911, P=0.000). All the incisions healed by first intention, and there was no wound infection and other early postoperative related complications. All patients were followed up 13-18 months (mean, 14.6 months). The fractures in both groups healed at 3 months after operation. No knee pain, limited movement, or other complications occurred. At 3 and 12 months after operation, the IKDC score, Lysholm score, knee range of motion, and the difference of posterior relaxation of bilateral knee joints in both groups were significantly improved when compared with preoperative ones, and further improved at 12 months after operation when compared with at 3 months after operation ( P<0.05). At each time point after operation, the above indexes and the grade of the difference of posterior relaxation of bilateral knee joints in the trial group were significantly better than those in the control group ( P<0.05). CONCLUSION: Arthroscopic suture bridge technique in the treatment avulsion fracture of PCL insertion is simple and reliable, which can significantly improve the function and stability of the knee joint and obtain satisfactory early effectiveness.

Long non-coding RNA LINC00426 contributes to doxorubicin resistance by sponging miR-4319 in osteosarcoma.

BACKGROUND: LINC00426 is a newly identified long non-coding RNA (lncRNA) with unacknowledged biological roles. Here we set out to characterize the expression status of LINC00426 in osteosarcoma and understand its mechanistic involvement in incidence of doxorubicin (Dox) resistance. METHODS: The relative expression of LINC00426 and miR-4319 was determined by real-time PCR. Cell viability and proliferation in response to LINC00426 silencing or miR-4319 over-expression was measured with CCK-8 kit and colony formation assay, respectively. The direct association between LINC00426 and miR-4319 was analyzed by pulldown assay with biotin-labelled probes. RESULTS: LINC00426 was significantly up-regulated in Dox-resistant osteosarcoma (OS) both in vitro and in vivo, which intimately associated with unfavorable prognosis. SiRNA-mediated knockdown of LINC00426 remarkably compromised cell viability and proliferation in Dox-resistant OS cells, which accompanied with decrease of IC50 and activation of caspase-3. We further predicted and validated the regulatory effects of miR-4319 on LINC00426 expression. Simultaneously, we provided evidences in support of direct binding between LINC00426 and miR-4319 by pulldown assay. Reciprocally negative regulation was observed between LINC00426 and miR-4319 each other. CONCLUSION: Ectopic introduction of miR-4319 significantly surmounted the Dox resistance in OS cells, while miR-4319 inhibition in LINC00426-deficient cells greatly restore this phenotype. We uncovered the important contribution of LINC00426/miR-4319 to Dox resistance in osteosarcoma. REVIEWERS: This article was reviewed by Bo Liang and Sinan Zhu.

[Clinical study on reconstruction of posterior cruciate ligament with platelet rich plasma combined with 3-strand peroneus longus tendons].

OBJECTIVE: To investigate the effectiveness of the reconstruction of posterior cruciate ligament (PCL) with platelet rich plasma (PRP) and 3-strand peroneal longus tendons under arthroscope. METHODS: Between June 2014 and December 2017, 58 patients with PCL rupture were randomly divided into two groups: the trial group (PRP assisted reconstruction of 3-strand peroneal longus tendons) and the control group (4-strand hamstring tendon reconstruction alone), 29 cases in each group. There was no significant difference in gender, age, injury side, Kellgren-Lawrence grade, time from injury to operation, and preoperative American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, International Knee Documentation Committee (IKDC) score, Lysholm score between the two groups ( P>0.05). Before operation, at 3 months and 12 months after operation, the IKDC score and Lysholm score of the two groups were recorded to evaluate the knee joint function, AOFAS ankle-hindfoot score was used to evaluate ankle function; KT-2000 examination (knee flexion of 90°, 30 lbs) was used to evaluate the difference of bilateral knee joint posterior relaxation at 12 months after operation, and MRI was used to evaluate ligament reconstruction; CT was used to evaluate the bone tunnel expansion of femur and tibia at 3 months and 12 months after operation. RESULTS: The operation was completed successfully in both groups, there was no complication in the donor tendon area. All the incisions healed by first intention. All the patients were followed up for more than 1 year. The follow-up time of the trial group was 13-17 months, with an average of 15.0 months; that of the control group was 15-20 months, with an average of 15.4 months. At 3 and 12 months after operation, there was no significant difference in AOFAS ankle-hindfoot score when compared with preoperative score and between the two groups ( P>0.05). At 3 and 12 months after operation, the IKDC score and Lysholm score of the two groups were significantly improved, and further improvement was found at 12 months when compared with at 3 months ( P<0.05); the scores in the trial group were significantly better than those of the control group ( P<0.05). At 12 months after operation, the difference of the posterior relaxation of the bilateral knees in the trial group was less than 5 mm in 27 cases, 6-10 mm in 2 cases; in the control group was less than 5 mm in 20 cases, 6-10 mm in 6 cases, and >10 mm in 3 cases; the difference between the two groups was not significant ( Z=0.606, P=0.544). At 12 months after operation, MRI of knee joint showed that all patients had good PCL graft. The MRI score of the trial group was better than that of the control group ( t=2.425, P=0.019). CT examination at 3 and 12 months after operation showed that the bone tunnel expansion of femur and tibia in the trial group were significantly better than those in the control group ( P<0.05). CONCLUSION: PRP combined with 3-stand peroneal longus tendons can significantly improve the function and stability of knee joint, effectively promote graft remodeling, and promote tendon bone healing, reduce the expansion of bone tunnel. The effectiveness is satisfactory.

[EFFECTIVENESS COMPARISON OF ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION BY LONG FIBULAR MUSCLE TENDON AND HAMSTRING TENDON].

OBJECTIVE: To compare the effectiveness of anterior cruciate ligament (ACL) reconstruction between by long fibular muscle tendon and by hamstring tendon under arthroscopy after ACL rupture. METHODS: Between February 2010 and December 2012, 56 cases of ACL rupture underwent ACL reconstruction under arthroscopy. The long fibular muscle tendon was used in 26 cases (group A) and the hamstring tendon was used in 30 cases (group B). There was no significant difference in gender, age, side, disease duration, and preoperative Lachman test, Lysholm score, and the International Knee Documentation Committee (IKDC) score between 2 groups (P > 0.05). The treatment after operation was identical in 2 groups. RESULTS: Primary healing of incision was obtained after operation in 2 groups. There was no major neurovascular injury and knee synovitis. There was no significant difference in operation time, hospitalization time, and postoperative 24-hour drainage volume between 2 groups (P > 0.05). The patients were followed up 25-32 months (mean, 28 months) in group A, and 27-37 months (mean, 31 months) in group B. There was no related complication at donor site in 2 groups. MRI examination showed good ACL reconstruction. The Lysholm score and the IKDC score of group A at 6 months after operation were significantly better than those of group B (P < 0.05), but no significant difference was found between 2 groups at 2 years after operation (P > 0.05). There was no significant difference in Lachman score between 2 groups at 6 months and 2 years after operation (P > 0.05). CONCLUSION: The long fibular muscle tendon for arthroscopic reconstruction of ACL has much simpler operation, earlier knee function recovery, and better subjective satisfaction than the hamstring tendon.