ObjectiveTo compare the incidence of chondral injury using Rigidfix femoral fixation device via the anteromedial approach and the tibial tunnel approach during anterior cruciate ligament (ACL) reconstruction. MethodsEighteen adult cadaver knees were divided randomly into 2 groups, 9 knees in each group. Femoral tunnel drilling and cross-pin guide insertions were performed using the Rigidfix femoral fixation device through the anteromedial approach (group A) and the tibial tunnel approach (group B). ACL reconstruction simulation was performed at 0, 10, 20, 30, 45, 60, 70, 80, and 90°in the horizontal position. The correlation between incidence of chondral injury and slope angles was analyzed, and then the incidence was compared between the 2 groups. ResultsThe correlation analysis indicated that the chondral injury incidence increased with the increasing of the slope angle (r=0.611, P=0.000; r=0.852, P=0.000). The incidence of chondral injury was 69.1% (56/81) and 48.1% (39/81) in groups A and B respectively, showing significant difference (χ2=7.356, P=0.007). The sublevel analysis showed that the chondral injury incidence of group A (36.1%, 13/36) was significantly higher than that of group B (0) at 0-30°(χ2=15.864, P=0.000), but no significant difference was found between group A (95.6%, 43/45) and group B (86.7%, 39/45) at 45-90°(P=0.267). ConclusionIt has more risk of chondral injury to use Rigidfix femoral fixation device via the anteromedial approach than the tibial tunnel approach to reconstruct ACL.
OBJECTIVE: To study the characteristics of, morphology histology and ultrastructure of anterior cruciate ligament(ACL) autograft and two-step cryopreserved ACL allograft after transplantation. METHODS: Sixty New Zealand rabbits and sixty Japanese rabbits were randomly divided into two groups: ACL autograft group and two-step cryopreserved ACL allograft group. Immunosuppressant were not used after transplantation. The histology and ultrastructure of the ACL of transplantation and normal knee were observed after 4 weeks and 12 weeks, respectively. RESULTS: The rate of remodeling process was faster in ACL autograft than in two-step cryopreserved ACL allograft, but there was similar remodeling process between two groups 12 weeks after transplantation. The proportions of large-diameter fibers(gt; or = 80 nm) of ACL autograft and cryopreserved ACL allograft were 6% and 24% in the 4th week, and were 0 and 2% in the 12th week, respectively. The proportions of small-diameter of fibers(lt; 80 nm) of ACL autogrft and cryopreserved ACL allograft were 94% and 76% in the 4th week, and 100% and 98% in the 12th week, respectively. Histologic incorporation in ACL autograft was similar to that in cryopreserved ACL allograft. CONCLUSION: Two-step cryopreserved bone-ACL-bone allograft were similar to bone-ACL-bone autograft cryopreserved in remodeling process and histology. The rate of remodeling process was faster in ACL autograft than in cryopreserved ACL allograft.
Objective To study the feasibility of virtual intercondylar notchplasty by applying MRI two-dimensional (2D) images to reconstruct three-dimensional (3D) images and measure the size of intercondylar notch. Methods Thirty healthy volunteers who had no knee joint disease and surgery history were selected. There were 15 females and 15 males with an age range of 20-30 years, weight range of 45-74 kg, and height range of 150-185 cm. They were divided into male group and female group, and the knees of each group were divided into 2 subgroups (the left group and right group). MRI scan of the left and right knees was performed, and the 2D images of MRI were imported into Mimics10.01 medical image control system for 3D reconstruction. The related anatomical data as follows were measured from the 3D digital model and analyzed by statistical software: notch width (NW), condylar width (CW), and notch width index (NWI). Then the 3D knee images of patients with anterior cruciate ligament (ACL) injury were collected between January and March 2010, and 4 patients with narrow intercondylar notch (NWI≤0.2) were selected for reconstructing the 3D model of the knee and simulating the intercondylar notch plasty. Then, the volume of osteotomy in 3D model was calculated and applied in the ACL reconstruction surgery, and whether the graft had impingement with intercondylar notch or not was evaluated. Results There were significant differences in NW and CW between male group and female group (P≤lt;≤0.05), but no significant difference was found in the NWI (P≤gt;≤0.05). And there was no significant difference in NW, CW, and NWI between the left and right knees both in male group and female group (P≤gt;≤0.05). After ACL reconstruction and intercondylar notchplasty, the shape of intercondylar notch became normal (NWI≤gt;≤0.22), no impingement occurred between the graft and intercondylar notch under arthroscopy within 3-month follow-up. Conclusion The shape of intercondylar notch of 3D model based on MRI 2D images is similar to the real intercondylar notch. NWI is one of important indexes which can reflect the narrow level of intercondylar notch. The virtual intercondylar notchplasty may provide preoperative plan and guidence for ACL reconstruction operation to avoid the impingement between graft and intercondylar notch after surgery.
ObjectiveTo investigate the effects of different concentrations of osteoprotegerin (OPG) combined with deproteinized bone (DPB) on the bone tunnel after the anterior cruciate ligament (ACL) reconstruction. MethodsThe femoral epiphyseal side was harvested from newborn calf, and allogenic DPB were prepared by hydrogen peroxide-chloroform/methanol method. Then, DPB were immersed in 3 concentrations levels of OPG (30, 60, 100 μg/mL) and 3 concentration ratios (30%, 60%, 100%) of the gel complex were prepared. Sixty healthy New Zealand white rabbits, male or female, weighing (2.7±0.4) kg, were divided randomly into 4 groups (n=15):control group (group A), 30% (group B), 60% (group C), and 100% (group D) OPG/DPB gel complex. The ACL reconstruction models were established by autologous Achilles tendon. Different ratios of OPG/DPB gel complex were implanted in the femoral and tibial bone tunnel of groups B, C, and D, but group A was not treated. The pathology observation (including the percentage of the femoral bone tunnel enlargement) and histological observation were performed and the biomechanical properties were measured at 4, 8, and 12 weeks after operation. ResultsOne rabbit died of infection in groups A and D, 2 rabbits in groups B and C respectively, and were added. General pathology observation showed that the internal orifices of the femoral and tibia tunnels were covered by a little of scar tissue at 4 weeks in all groups. At 8 weeks, white chondroid tissues were observed around the internal orifices of the femoral and tibia tunnels, especially in groups C and D. At 12 weeks, the internal orifices of the femoral and tibia tunnels enlarged in groups A, B, and C, but it was completely closed in group D. At each time point, the rates of the femoral bone tunnel enlargement in groups B, C, and D were significantly lower than that in group A, and group D was significantly lower than groups B and C (P<0.05); group C was significantly lower than group B at 8 weeks, but no significant difference was found at 4 and 12 weeks (P<0.05). Hisological observation showed that fresh fibrous connective tissue was observed in 4 groups at 4 weeks; there was various arrangements of Sharpey fiber in all groups at 8 weeks and the atypical 4-layer structure of bone was seen in group D; at 12 weeks, Sharpey fiber arranged regularly in all groups, with typical 4-layer structure of bone in groups B, C, and D, and an irregular "tidal line" formed, especially in group D. Biomechanics measurement showed that the maximum tensile load in group D was significantly higher than that in groups A and B at 4 weeks (P<0.05), but no significant difference was shown among groups A, B, and C, and between groups C and D (P>0.05); at 8 weeks, it was significantly higher in groups C and group D than group A, and in group D than group B (P<0.05), but there was no significant difference between groups A, C and group B (P>0.05); at 12 weeks, it was significantly higher in groups C and D than groups A and B, and in group D than group C (P<0.05), but difference was not significant between groups A and B (P>0.05). ConclusionDifferent concentrations ratios of OPG/DPB gel complexes have different effects on the bone tunnel after ACL reconstruction. 100% OPG/DPB gel complex has significant effects to prevent the enlargement of bone tunnel and to enhance tendon bone healing.
Objective?To evaluate the feasibility of the anterior cruciate ligament (ACL) reconstruction with 6 strands of hamstring tendons enveloped by periosteum.?Methods?Between April 2008 and April 2009, 34 patients with ACL injury were treated, ACL of whom was reconstructed with 6 strands of hamstring tendons enveloping of periosteum and double Rigidfix fixation. There were 30 males and 4 females, aged 19-54 years with an average of 29.4 years. The causes of injury included sport in 19 cases, traffic accident in 8 cases, falling from height in 5 cases, and other in 2 cases. The locations were left knee in 19 cases and right knee in 15 cases. The disease duration was 3 weeks to 18 months (median, 9.4 months). The results of Lachman test and anterior drawer test were positive. The Lysholm knee score was 61.5 ± 3.6. MRI examination revealed ACL rupture in 26 cases and ACL injury in 8 cases.?Results?All incisions healed by first intention, and no early complication occurred. Twenty-eight cases were followed up 12-32 months (mean, 16.1 months). The result of Lachman test was negative at 12 months after operation; in all patients, knee extension reached 0°, and flexion reached 120-150° (mean, 132.5°). The AP and lateral X-ray films and MRI showed no bone tunnel expansion. At last follow-up the therapeutic effect evaluation was excellent in 25 cases, good in 1 case, and fair in 2 cases; the excellent and good rate was 92.9%. The postoperative Lysholm score was 91.0 ± 3.2, showing significant difference when compared with preoperative score (t=32.78, P=0.00). ?Conclusion?Six strands of hamstring tendons can ensure sufficient tensile strength, and use of the double Rigidfix absorbable screw makes fixation more reliable. Facing outside suture of periosteal flap can promote tendon-bone healing, so it is a good method of ACL reconstruction.
ObjectiveTo prepare the small intestinal submucosa (SIS)-silk composite scaffold for anterior cruciate ligament (ACL) reconstruction, and to evaluate its properties of biomechanics, biocompatibility, and the influence on synovial fluid leaking into tibia tunnel so as to provide a better choice in the clinical application of ACL reconstruction. MethodsThe silk was used to remove sericin and then weaved as silk scaffold, which was surrounded cylindrically by SIS to prepare a composite scaffold. The property of biomechanics was evaluated by biomechanical testing system. The cell biocompatibility of scaffolds was evaluated by live/dead staining and the cell counting kit 8 (CCK- 8). Thirty 6-week-old Sprague Dawley rats were randomly assigned to 2 groups (n=15). The silk scaffold (S group) and composite scaffold (SS group) were subcutaneously implanted. At 2, 4, and 8 weeks after implanted, the specimen were harvested for HE staining to observe the biocompatibility. Another 20 28-week-old New Zealand white rabbits were randomly assigned to the S group and SS group (n=20), and the silk scaffold and composite scaffold were used for ACL reconstruction respectively in 2 groups. Furthermore, a bone window was made on the tibia tunnel. At last, the electric resistance of tendon graft in the bone window was measured and recorded at different time points after 5 mL of 10% NaCl or 5 mL of ink solution was irrigated into the joint cavity recspectively. ResultsThe gross observation showed that the composite scaffold consisted of the helical silk bundle inside which was surrounded by SIS. The maximal load of silk scaffold and composite scaffold was respectively (138.62±11.41) N and (137.05±16.95) N, showing no significant difference (P>0.05); the stiffness was respectively (24.65±2.62) N/mm and (24.21±2.39) N/mm, showing no significant difference (P>0.05). The live/dead staining showed that the cells had good activity on both scaffolds. However, the cells on the composite scaffold had better extensibility. In addition, the cell proliferation curve indicated that no significant difference in the absorbance (A) values was founded between groups at various time points (P>0.05). HE staining showed less inflammatory cells and much more angiogenesis in SS group than in S group at 2, 4, and 8 weeks after subcutaneously implanted (P<0.05), indicating good biocompatibility. Additionally, the starting time points of electric resistance decrease and the ink leakage were both significantly later in SS group than in S group (P<0.05). The duration of ink leakage was significantly longer in SS group than in S group (P<0.05). ConclusionThe SIS-silk composite scaffold has excellent biomechanical properties and biocompatibility and early vacularization after in vivo implantation. Moreover, it can reducing the leakage of synovial fluid into tibia tunnel at the early stage of ACL reconstruction. So it is promising to be an ideal ACL scaffold.
To analyze the effectiveness of anterior cruciate l igament (ACL) reconstruction with preserving the remnant ACL by allograft l igament. Methods Between January and July in 2008, 97 patients underwent ACL reconstruction with the allograft l igament. On the basis of the ACL’s condition, patients were divided into 2 groups. In the trial group (patients having remnant ACL, n=38), there were 27 males and 11 females with an average age of 24.3 years (range, 16-43 years); of them, 8 cases compl icated by menicus injury and 13 cases by Outbridge I degree cartilage injury; the time from injuryto operation was 3-20 weeks (mean, 8.6 weeks). In the control group (patients having no remnant ACL, n=59), there were 35 males and 24 females with an average age of 27.8 years (range, 18-48 years); of them, 16 cases compl icated by menicus injury and 23 cases by Outbridge I degree cartilage injury; the time from injury to operation was 4-44 weeks (mean, 12.7 weeks). All injuries were caused by sports in 2 groups. All patients had positive anterior drawer test and positive Lackman test. Before operation and 3, 8, 9, 15 months after operation, the function of the knee joint was evaluated by the International Knee Documentation Committee (IKDC) scale and Lysholm score. KT-2000 arthrometer was used to evaluate knee laxity. Results All incisions healed primarily, and no intraarticular infection occurred. Thirty-seven cases and 57 cases were followed up 15 months in the trial group and the control group, respectively. Knee instabil ity disappeared; the patients showed negative anterior drawer test and negative Lackman test. By the evaluation of KT-2000, the joint sl ippage of 2 groups were less than 2 mm at 3 and 6 months after operation, but it was more than 2 mm in 2 cases of the trial group and in 3 cases of the control group at 9 months after operation; and it was no change in the trial group and 2.5-4.0 mm (mean, 3.4 mm) in the control group at 15 months after operation. Both the IKDC scale and Lysholm score were higher in the trial group than in the control group 3 months after operation, but the differences were not significant (P gt; 0.05). Both the IKDC scale and Lysholm score were
ObjectiveTo compare the effectiveness of anterior cruciate ligament (ACL) reconstruction between by long fibular muscle tendon and by hamstring tendon under arthroscopy after ACL rupture. MethodsBetween 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. ResultsPrimary 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). ConclusionThe 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.
Aiming at the problems of low accuracy and large difference of segmentation boundary distance in anterior cruciate ligament (ACL) image segmentation of knee joint, this paper proposes an ACL image segmentation model by fusing dilated convolution and residual hybrid attention U-shaped network (DRH-UNet). The proposed model builds upon the U-shaped network (U-Net) by incorporating dilated convolutions to expand the receptive field, enabling a better understanding of the contextual relationships within the image. Additionally, a residual hybrid attention block is designed in the skip connections to enhance the expression of critical features in key regions and reduce the semantic gap, thereby improving the representation capability for the ACL area. This study constructs an enhanced annotated ACL dataset based on the publicly available Magnetic Resonance Imaging Network (MRNet) dataset. The proposed method is validated on this dataset, and the experimental results demonstrate that the DRH-UNet model achieves a Dice similarity coefficient (DSC) of (88.01±1.57)% and a Hausdorff distance (HD) of 5.16±0.85, outperforming other ACL segmentation methods. The proposed approach further enhances the segmentation accuracy of ACL, providing valuable assistance for subsequent clinical diagnosis by physicians.
Objective To investigate the effectiveness of portable bracket of lower limb in the reconstruction of anterior cruciate l igament (ACL) by the long fibular muscle tendon under arthroscopy. Methods Between March 2008 and September 2010, 22 patients with ACL injury were treated. The limb position was maintained by portable bracket of lower limb and ACL was reconstructed with the long fibular muscle tendon under arthroscopy. There were 15 males and 7 females with an average age of 33.8 years (range, 19-64 years). The causes of ACL injury were traffic accident injury in 14 cases, sport trauma in 5 cases, and fall ing injury in 3 cases. The locations were the left knee in 10 cases and the right knee in12 cases, including 12 fresh injuries and 10 old injuries. Of 22 patients, 17 had positive anterior drawer test, 19 had positive pivot shift test, and 20 had positive Lachman test. According to International Knee Documentation Committee (IKDC) criteria, there were 6 abnormal and 16 severely abnormal. The subjective IKDC score was 57.64 ± 6.11. The Lysholm score was 55.45 ± 4.37. Results All incisions healed by first intention, and no complication was found. All patients were followed up 9-38 months (mean, 15 months). At last follow-up, the flexion of the knee ranged from 120 to 135° (mean, 127°). One patient had positive anterior drawer test, 1 patient had positive pivot shift test, and 2 patients had positive Lachman test. No ligament loosening and breakage occurred. According to the IKDC criteria, 10 patients rated as normal, 11 patients as nearly normal, and 1 patient as abnormal. The subjective IKDC score was 90.44 ± 6.11, showing significant difference when compared with preoperative one (t=4.653, P=0.021). The Lysholm score was 90.12 ± 5.78, showing significant difference when compared with preoperative one (t=4.231, P=0.028). Conclusion Portable bracket of lower limb in the reconstruction of ACL has the advantages of saving manpower and easy operation. The long fibular muscle tendon is enough long and b to reconstruct the ACL, which can increase the contact surface between the tendon and bone and is beneficial to tendon-bone heal ing.