The purpose of this study was to determine the incidence of graft-tunnel mismatch (GTM) when performing anatomic anterior cruciate ligament reconstruction (ACLR) using bone-patella tendon-bone (BPTB) grafts and anteromedial portal drilling. Beginning in November 2018, 100 consecutive patients who underwent ACLR by two sports fellowship-trained, orthopedic surgeons using BPTB autograft and anteromedial portal drilling were prospectively identified. The BPTB graft dimensions and the femoral tunnel distance, tibial tunnel distance, intra-articular distance, and total distance were measured. Surgeons determined the depth and angle of tunnels based on the patella tendon graft length dimensions in each case. After passage of the graft, the distance from the distal graft tip to the tibial cortex aperture was measured. GTM was defined as the need for additional measures to obtain satisfactory tibial graft fixation (< 1 5e20 mm of bone fixation). The incidence of mismatch was 6/100 (6%). Five cases involved the graft being too long, with the tibial bone plug protruding excessively from the tibial tunneld4/5 had a patella tendon length ? 50 mm. Three cases were managed with femoral tunnel recession, and two were treated with a free bone plug technique. One patient with a patella tendon length of 35 mm had a graft that was too short, with the tibial bone plug recessed in the tibial tunnel. Of patients whose tibial tunnel distance was within 5 mm of the patella tendon length, only 1/46 (2%) patients had mismatch, whereas 5/54 (9%) of patients who had >5 mm difference had mismatch. The incidence of grafttunnel mismatch after anatomic ACLR using BTPB and anteromedial portal drilling in this study is 6%. To limit the occurrence of GTM where the graft is too long, surgeons should drill tibial tunnel distances within 5 mm of the patella tendon length

Background. Surgical reconstruction of the anterior cruciate ligament is a common practice to treat the disability or chronic instability of the knee. Several factors associated with success or failure of the ACL reconstruction, including surgical technique and graft material and graft tension. We aimed to show how we can optimize the graft properties and achieve better post surgical outcomes during ACL reconstruction using 3-dimensional computational finite element simulation. Methods. In this paper, 3-dimensional model of the knee was constructed to investigate the effect of graft tensioning on the knee joint biomechanics. Four different grafts were compared: 1) bone-patellar tendon-bone graft (BPTB) 2) Hamstring tendon 3) BPTB and a band of gracilis 4) Hamstring and a band of gracilis. The initial graft tension was set as “0, 20, 40, or 60N”. The anterior loading was set to 134 N. Findings. Our study shows that the use of the discarded gracilis tendon, which usually excised after graft fixation, could be associated with a host of merits. Our results show that preserving this excess part of gracilis would decrease the required pretention load and, subsequently, could optimize biomechanical properties of the knee. Conclusion. Required pretension during surgery will have decreased significantly by adding a band of gracilis to the proper graft. Therefore, in addition to achieving normal stability of the knee, we can have lower risk of degradation

No consensus exists regarding the optimal graft choice between allogenic and autologous graft. Incidence of septic arthritis following ACL reconstruction is rare but may dependent on the graft type. Our meta-analysis assesses the difference in incidence of septic arthritis after ACL reconstruction across three groups of grafts: hamstring autografts, bone patellar tendon bone (BPTB) autografts and allografts of any type. A literature search was performed without language restriction on PubMed and EMBASE databases. We identified 245 infected ACL grafts across 15 included studies that provided a breakdown of infection incidence by graft type. A meta-analysis was performed using a random-effects model to estimate the overall infection rates and those for different graft types. Summary risk ratios and 95% confidence intervals (CIs) were calculated and reported for each outcome. Publication bias with respect to infection rates was estimated using a funnel plot. Our meta-analysis shows an overall ACL graft infection rate of 0.6% (CI 0.3% – 1.3%). The incidence was highest in autologous hamstring grafts at 1.1% at (CI 0.8% – 1.6%). That of allografts and autologous BPTB grafts was similar at 0.5% (CI 0.2%–1.0%) and 0.4% (CI 0.2% – 0.7%), respectively. Full breakdown of the meta-analysis results by study and graft type is reported in Figure 1. Septic arthritis after ACL reconstruction remains a rare (<1%) but a serious complication. Allograft rates of infection were not higher than those the autografts, contrary to the theoretical concerns. Therefore a higher infection risk should not be cited as a reason for not using it. The reason for the apparently higher infection rate with hamstring autografts is unclear and requires further research. The results of our meta-analysis may aid informed discussions between surgeons and patients about the risk of infection after ACL reconstructive surgery and graft choice

Transverse pin femoral fixation of bone-patella tendon-bone (BPTB) in ACL reconstruction has been widely applied during the last decades. Aim of our study is to confront two different system of transverse femoral fixation for BPTB graft: Transfix BTB (Arthrex) and BioTransfix T3 (Arthrex). The main differences between these two system are the diameter (3.0 mm Transfix BTB and 3.5 mm BioTransfix T3), and section (Transfix BTB is cannulated). Surgical technique adopts the same transverse vectorial guide but different guide sleeves. 30 fresh-frozen porcine knees (mean age 2.2 years) were assigned to the two groups randomisedly. the patellar bone block and tendon were harvested using the same size in all specimens (10mm × 25 mm, 10 mm). Zwick-Roell z010 tension/compression device with bone clamps, was used for the study:. Cyclic test (1000 cycles, 0.5 Hz, 50–250 N/cycle, 100 cycles of preload). Final pull-out test (1 mm/s). Failure analysis. CT scan and densitometry. Any implant didn't fail during cyclic test. The elongation average was 1.85±0.63 for Transfix BTB and 1.69±0.87 for BioTransfix T3. Pull-out test showed very similar values in terms of Ultimate Strength Failure (USF), Stiffness at USF, and Stiffness:. The failure mode was bone plug fracture (12 for Transfix BTB and 13 for BioTransfix T3) and tendon failure (3 for Transfix BTB and 2 for BioTransfix T3). The post-test CT scan showed any failure of the fixation devices and the correct position inside the femoral half-tunnel. The mean bone density of porcine femora was comparable to young human femora (1.12±0.31 BMD). Both systems showed a similar behaviour in terms of USF, Stiffness, Cyclic load, method of failure and other biomechanical parameters. The reproducibility of surgical technique, the mechanical strength and endurance of the systems suggest two valid options for ACL reconstruction with BPTB even if in-vivo studies are necessary to confirm the animal ex-vivo biomechanical data

Purpose. Twelve case reports of distal femur fractures as post-operative complications after anterior cruciate ligament (ACL) reconstruction have been described in the literature. The femoral tunnel has been suggested as a potential stress riser for fracture formation. The recent increase in double bundle ACL reconstructions may compound this risk. This is the first biomechanical study to examine the stress riser effect of the femoral tunnel(s) after ACL reconstruction. The hypotheses tested in this study are that the femoral tunnel acts as a stress riser to fracture and that this effect increases with the size of the tunnel (8mm versus 10mm) and with the number of tunnels (one versus two). Method. Femoral tunnels simulating single bundle (SB) hamstring graft (8 mm), bone-patellar tendon-bone graft (10 mm), and double bundle (DB) ACL reconstruction (7mm, 6 mm) were drilled in fourth generation saw bones. These three experimental groups and a control group consisting of native saw bones without tunnels, were loaded to failure. Result. All fractures occurred through the tunnels in the double tunnel group whereas fractures did not consistently occur through the tunnels in the single tunnel groups. The mean fracture load was 6145 N 471 N in the native group, 5691 N 198 N in the 8 mm single tunnel group, 5702 N 282 N in the 10 mm single tunnel group, and 4744 N 418 N in the double tunnel group. The mean fracture load for the double tunnel group was significantly different when compared to native, 8 mm single bundle, and 10 mm single bundle groups independently (p value = 0.0016, 0.0060, and 0.0038 respectively). No other statistically significant differences were identified. Conclusion. An anatomically placed femoral tunnel in single bundle ACL reconstruction in our experimental model was not a stress riser to fracture, whereas the two femoral tunnels in double bundle ACL reconstruction significantly decreased load to failure. The results support the sparcity of reported peri-ACL reconstruction femur fractures in single femoral tunnel techniques. However, the increased fracture risk in double bundle ACL reconstruction is a cause for concern and may impact patient selection