Objective The anterior cruciate l igament (ACL) is the important stable structure of the knee. To evaluate the method and outcome of bone-ACL-bone (B-ACL-B) allograft under arthroscope in reconstruction of ACL. Methods Between October 2007 and February 2010, arthroscopic ACL reconstruction with deep-freezing B-ACL-B allograft was performed on 22 patients with ACL ruptures. There were 15 males and 7 females with an average age of 27.6 years (range, 19-55 years). The causes of ACL rupture were sport trauma in 12 cases, fall ing injury in 1 case, heavy crush in 2 cases, and traffic accident in 7 cases. The locations were the left knee in 14 cases and the right knee in 8 cases. The disease durationwas 7 days to 12 months (median, 65 days). Nineteen patients showed the positive results of anterior drawer test and pivot shift test, and 21 patients showed the positive results of Lachman test. According to International Knee Documentation Committee (IKDC) criteria, there were 5 abnormal and 17 severely abnormal. The subjective IKDC score was 49.6 ± 6.9. The Lysholm score was 48.5 ± 5.3. The Tegner scale scores were 6.8 ± 1.2 before injury and 2.1 ± 0.5 before operation. The MRI showed the ACL injuries in 18 of 20 patients. Results The mean operative time was 75 minutes (range, 65-85 minutes); the mean blood loss was 110 mL (range, 80-150 mL). All incisions healed by first intention. No immunologic rejection and deep vein thrombosis of lower l imbs occurred. All patients were followed up 7-34 months (mean, 18 months). At last follow-up, the flexion of the knee ranged from 125 to 135° (mean, 130.5°). Two patients showed the positive results of anterior drawer test, 1 patient showed the positive result of pivot shift test, and 3 patients showed the positive results of Lachman test. According to the IKDC criteria, 10 patients rated as normal, 11 patients as nearly normal, 1 patient as abnormal. The subjective IKDC score was 90.0 ± 5.8, showing significant difference when compared with preoperative one (t=4.653, P=0.021). The Lysholm score was 91.6 ± 7.1, showing significant difference when compared with preoperative one (t=4.231, P=0.028). The Tegner scale score was 6.1 ± 1.5, showing no significant difference when compared with one before injury (t=1.321, P=0.070) and showing significant difference when compared preoperative one (t=3.815, P=0.033). The arthroscopic examination showed no rupture of grafts in 19 patients, 17 grafts showed normal tension, and 2 showed sl ight relaxation at 6 months after operation. Conclusion Reconstruction of the ACL with B-ACL-B allograft under arthroscope is a safe and effective method, which can anatomically reconstruct ACL and obtain a good recovery of the knee function after operation.
Objective To review the research progress regarding the over-the-top technique for anterior cruciate ligament (ACL) reconstruction. MethodsThe relevant literature on ACL reconstruction using the over-the-top technique was analyzed for its evolution, clinical application, advantages, and limitations. Results Over-the-top technique for ACL reconstruction is a combined intra- and extra-articular technique. Because it avoids drilling the femoral tunnel, its advantages are mainly highlighted in the protection of the femur. Therefore, it is widely used in children and adolescents with epiphyseal occlusion and in patients with revision reconstruction. In addition, significant improvements in postoperative joint stability, functional scores, and return to exercise rates are found in long-term follow-up studies of patients with primary ACL reconstruction and combined anterolateral tenodesis. However, the technique also has some limitations, such as poor stability of knee flexion after operation, high requirement for graft length, and easy impact of graft in the intercondylar fossa. Conclusion The current research results show the effectiveness and safety of the over-the-top technique for primary and revision ACL reconstruction, with the advantages of wide application, simple operation, and quick recovery; however, more researches are needed to further optimize the selection of grafts and femoral condyle management problems, and to clarify the long-term effectiveness.
ObjectiveTo investigate the effect of the femoral tunnel angle on the femoral tunnel after anterior cruciate ligament (ACL) reconstruction in rabbits. MethodsFifty-four healthy 4-5 months old rabbits (weighing, 1.8-2.3 kg, male or female) were randomly divided into 3 groups (n=18). The ACL reconstruction models of the right knee were established in 3 experimental groups using its Achilles tendons, and the left knee served as the control group. On the coronal position, the angle between the femoral tunnel and the femoral shaft axis was 30°, 45°, and 60°. The level of tumor necrosis factor α (TNF-α) in the synovial fluid at 1, 2, and 4 weeks, the maximum load of the ligament and the rate of bone tunnel enlargement at 4, 8, and 12 weeks were detected. ResultsThe level of TNF-α significantly increased, and the maximum load of the ligament significantly decreased in the 3 experimental groups when compared with ones in the control group (P<0.05), but no significant difference was found among 3 experimental groups (P>0.05). The bone tunnel enlargement was observed in 3 experimental groups at each time point and reached the peak at 4 weeks, but no significant difference was shown among 3 groups (P>0.05). ConclusionThe 30-60° angle between the femoral tunnel and the femoral shaft axis in the coronal position has no significant effect on the femoral tunnel enlargement after ACL reconstruction in rabbits.
Objective To summarize the evaluation methods of return to sports (RTS) after anterior cruciate ligament reconstruction (ACLR) in recent years, in order to provide reference for clinical practice. Methods The literature related to the RTS after ACLR was searched from CNKI, Wanfang, PubMed, and Foreign Medical Information Resources Retrieval Platform (FMRS) databases. The retrieval range was from 2010 to 2023, and 66 papers were finally included for review. The relevant literature was summarized and analyzed from the aspects of RTS time, objective evaluation indicators, and psychological evaluation. Results RTS is the common desire of patients with ACL injury and doctors, as well as the initial intention of selecting surgery. A reasonable and perfect evaluation method of RTS can not only help patients recover to preoperative exercise level, but also protect patients from re-injury. At present, the main criterion for clinical judgement of RTS is time. It is basically agreed that RTS after 9 months can reduce the re-injury. In addition to time, it is also necessary to test the lower limb muscle strength, jumping, balance, and other aspects of the patient, comprehensively assess the degree of functional recovery and determine the different time of RTS according to the type of exercise. Psychological assessment plays an important role in RTS and has a good clinical predictive effect. ConclusionRTS is one of the research hotspots after ACLR. At present, there are many related evaluation methods, which need to be further optimized by more research to build a comprehensive and standardized evaluation system.
ObjectiveTo investigate the best knee flexion angle by analyzing the length and orientation of the femoral tunnel through anteromedial portal (AM) at different flexion angles during anterior cruciate ligament (ACL) reconstruction. MethodsTwelve fresh cadaveric knees were selected to locate the center of ACL femoral footprint through AM using the improved hook slot vernier caliper, and to locate the posterior bone cortex using a diameter 3 mm ball at flexion of 90, 100, 110, 120, and 130°. The femoral tunnel length, standard coronal and sagittal plane angles, and the position relation between exit point and the lateral epicondyle were measured; the tunnel orientation on the anteroposterior and lateral X-ray films was also measured. ResultsWith increasing flexion of the knee, the femoral tunnel length showed a first increasing and then stable tendency; significant difference was found between at flexion of 90°and at flexions of 100, 110, 120, and 130°, and between flexions of 100°and 120°(P<0.05). The femoral tunnel showed a trend of decreasing with coronal angle, whereas gradually increasing with sagittal angle. The knee flexion angle had significant difference either among flexions of 90, 110, and 130°or between flexions of 100°and 120°(P<0.05). The exit point of the femoral tunnel located at the lateral epicondyle of the femur proximal to posterior region at flexion of 90°in all knees, and at flexion of 100°in 7 knees, but it located at the lateral epicondyle of the femur proximal to anterior region at flexion of 110, 120, and 130°in all knees. As the knee flexion angle increasing, the angle between femoral tunnel with the tangent of internal-external femoral condyle on anteroposterior X-ray films showed a trend of decreasing gradually, but a trend of increasing gradually on lateral X-ray films. On the anteroposterior X-ray films, significant differences were found in the angle either among flexions of 90, 110, and 130°or between flexions of 100°and 120°(P<0.05). On the lateral X-ray films, there were significant differences in the angle among flexions of 90, 100, 110, 120, and 130°(P<0.05). ConclusionDuring ACL reconstruction by AM, 110°is the best flexion angle, which can get the ideal femoral tunnel.
Objective Anterior cruciate l igament (ACL) is an important forward stable structure of knees, when its function impaired, the normal mechanical environment of joint will be destroyed. Now, to explore the effect of ACL rupture on the posterior horn of lateral meniscus by measuring biomechanics. Methods Ten specimens of knee joints (5 left and 5 right sides asymmetrically) were donated voluntarily from 10 normal fresh adult male cadavers, aged 26-35 years with anaverage of 31.4 years. The straining of lateral meniscus posterior horn in 10 knee joint specimens before and after resection of ACL were tested when the knee joints loaded from 0 to 200 N at a velocity of 0.5 mm per second at 0, 30, 60, and 90° of flexion and recorded at the moment when the load was 200 N, the ratio of straining before and after resection of ACL were connted. All the specimens were anatomied and observed in general so as to find injuries such as deformation and tearing in lateral meniscus after test. Results The straining of lateral meniscus posterior horn were as follows: intact ACL group, (—11.70 ± 0.95) με at 0° flexion, (—14.10 ± 1.95) με at 30° flexion, (—20.10 ± 1.20) με at 60° flexion, and (—26.50 ± 1.58) με at 90° flexion; ACL rupture group, (—6.20 ± 1.55) με at 0° flexion, (—26.30 ± 1.89) με at 30° flexion, (—37.70 ± 1.64) με at 60° flexion, and (—46.20 ± 2.78) με at 90° flexion. There were significant differences between intact ACL group and ACL rupture group (P lt; 0.05). The straining ratio of the posterior horn of lateral meniscus rupture ACL to intact ACL were 0.53 ± 0.12, 1.90 ± 0.31, 1.88 ± 0.15, and 1.75 ± 0.16 at 0, 30, 60, and 90° of flexion. The lateral meniscus were intact in general and no injuries such as deformation and tearingwere found. Conclusion ACL has a significant biomechanical effect on posterior horn of lateral meniscus. Consequently, the posterior horn of lateral meniscus is overloaded with ACL rupture at 30, 60, and 90° of flexion, and thereby, it will have the high risk of tear.
Objective To investigate the effect of lower limb rehabilitation robot combined with virtual reality training on walking ability after anterior cruciate ligament reconstruction (ACLR). Methods Patients after ACLR treated in the Rehabilitation Medical Center of the Second Hospital of Jiaxing between May 2019 and July 2021 were selected. The patients were randomly divided into two groups. The patients with conventional ACLR rehabilitation training + lower limb rehabilitation robot combined with virtual reality training were used as the treatment group, and only the patients with conventional ACLR rehabilitation training were used as the control group. The rehabilitation training lasted for 8 weeks. After 4 and 8 weeks of treatment, the two groups were evaluated by Lysholm knee score scale (LKSS), Holden walking score and Gait watch gait analysis. Results A total of 40 patients were included, with 20 patients in each group. There was no significant difference between the two groups in LKSS score, Holden walking score and Gait watch gait analysis dynamic data at 4 weeks of treatment (P>0.05). After 8 weeks of treatment, the LKSS score [(77.74±5.53) vs. (69.53±5.26) points], Holden walking score [(4.79±0.34) vs. (4.45±0.39) points] and Gait watch gait analysis dynamic data [step size: (78.35±2.43) vs. (73.64±3.35) cm, step frequency: (115.10±4.49) vs. (107.71±5.14) step/min, step speed: (108.63±8.55) vs. (96.78±8.47) cm/s] of the treatment group were better than those of the control group (P<0.05), The above indexes of the two groups were improved compared with those at 4 weeks of treatment (P<0.05). Conclusion Lower limb rehabilitation robot combined with virtual reality training can effectively improve walking ability after ACLR.
Objective The tendon-bone heal ing is the key point to ensure the success of the anterior cruciate l igament (ACL) reconstruction. To observe the histological change in the tendon-bone heal ing after ACL reconstruction by different concentrations of platelet-rich plasma (PRP) combined with deproteinized bone (DPB) of calf as bone tunnel infill ing and to investigate the active effect of the complex on tendon-bone heal ing and to define the optimal concentration of PRP. Methods Eight mL blood was drawn from central artery of New Zealand rabbit ears; PRP was prepared by Landesbergmethod, and l iquid supernatant was used as thinner to prepare different concentrations of PRP (30%, 60%, and 100%). Fresh osteoepiphysis spongy bone was harvested from lower end of femur of newborn calf to prepare DPB by way of 30% H2O2 and ether alternating soaking for 24 hours continuous 6 times. DPB was soaked in different concentrations of PRP and mixed with activator to prepare the PRP/DPB complex. A total of 54 New Zealand white rabbits, aging 8-12 months, weighing (2.5 ± 0.4) kg, were divided randomly into 3 groups: group A (30%PRP/DPB complex, n=18), group B (60%PRP/DPB complex, n=18), and group C (100%PRP/DPB complex, n=18). The legs of the rabbits were randomly divided into experimental side and the control side; ACL was reconstructed by semitendinosus and PRP/DPB complex in bone tunnel in the experimental side, and only by semitendinosus in the control side. The general conditions of the rabbits were observed postoperatively and HE staining was used to observe the tendon-bone heal ing, then I-IV levels of semi-quantitative analysis of the tendon-bone heal ing were evaluated according to Demirag standard at 3, 6, and 12 weeks. Results General observation: Synovial fluid sl ightly increased in the specimens and no bony tissue was found in inner of femoral tunnel at 3 weeks; there was no synovial fluid in all the specimens and scar tissue was discovered in inner of femoral tunnel at 6 weeks; and there was no synovial fluid and the tendons became tighter with fibrous tissue at 12 weeks. Histological observation: New granulation tissue formed in the tendon-bone interface of group A experimental sides at 3 weeks; there was various widths of Sharpey type textile fiber in the tendon-bone interface at 6 weeks; Sharpey type textile fiber arranged regularly, which formed an irregular and blur “tidal l ine” at 12 weeks. Group B experimental sides were better than any other group at 3, 6, and 12 weeks; chondrocyte-l ike arranged regularly in the tendonboneinterface at 3 weeks; the number of chondrocyte-l ike per unit area was more than that of the other groups at 6 weeks;and chondrocyte-l ike prol iferated and matured in the tendon-bone interface, Sharpey type textile fiber became tighter andordered. Group C experimental sides were similar to both sides of group A at 3 weeks, however, the prol iferation of relatively mature dense connective tissue was worse than that of other groups at 6 and 12 weeks. According to Demirag grading, there were significant differences in tendon-bone heal ing between the experimental sides and the control sides of group B at 3 and 6 weeks, and between group B experimental sides and group C experimental sides at 12 weeks (P lt; 0.05). Conclusion The mixture of PRP/PRP has good biocompatibil ity and bone induction, so it can enhance tendon-bone heal ing after ACL reconstruction when the concentration of PRP is 60%.
ObjectiveTo investigate the histological characteristics of autogenous hamstring grafts after anterior cruciate ligament (ACL) reconstruction.MethodsThe patients who underwent arthroscopic single-bundle ACL reconstruction with autogenous hamstring tendons and were followed up at least 4 years and also underwent second-look arthroscopy between March 2017 and December 2017 and met the selection criteria were considered for enrollment. Graft quality under arthroscopy was evaluated as good remodeling group (GRG, the total scores were 4-6) and poor remodeling group (PRG, the total scores were 1-3) according to synovial and vascular coverage, the apparent tension of the grafts, the thickness and retear of the grafts. During the second-look arthroscopic procedures, ACL graft biopsies were performed. Normal ACL tissues harvested from the patients under 60 years old who underwent total knee arthroplasty were designated as normal controls. Graft vascularity, cellular morphology, cellular metabolism, and collagen fibril distribution were analyzed.ResultsThe 18 specimens (11 cases of GRG group and 7 cases of PRG group) and 9 native ACL biopsied tissue sample were enrolled into the study. Arthroscopy scores were 2-6 (mean, 4.7). The biology under light microscopy of GRG group was similar to that of native ACL in control group. There was no significant difference in the scores of graft vascularity and cellular morphology between GRG group and control group (P>0.05), while PRG group was significantly lower than the other two groups (P<0.05). Transmission electron microscope evaluation showed that GRG group and control group had better collagen fibril distribution and lower levels of cellular metabolism than PRG group (P<0.05). There was no significant difference in cellular metabolism between GRG and control groups (P>0.05), while collagen fibril distribution score of GRG group was significantly lower than that of control group (P<0.05).ConclusionWhile good remodeling grafts under arthroscopy in histological maturation period was proved to be more similar to normal ACL on ultrastructure properties under light and electron microscope, ultra structural differences regarding collagen fibril distribution still persist.
ObjectiveTo investigate the value of ligament remnant preservation during anterior cruciate ligament (ACL) reconstruction by observing the integrity, the tension, the synovial membrane covering, and the color of the reconstructed ligament under arthroscopy. MethodsBetween January 2011 and December 2013, 122 patients who underwent ACL reconstruction and arthroscopic internal fixation removal at 1 year after reconstruction were included in this study. Of these cases, 61 cases underwent ACL reconstruction using the remnant-preserved technique (preservation group);the other 61 cases underwent ACL reconstruction using non remnant-preserved technique (non preservation group). There was no significant difference in gender, age, injury side, body mass index, type of injury, the time from injury to reconstruction, and the result of KT-2000 examination between 2 groups (P<0.05). The reconstructed ACL were observed under arthroscopy when internal fixation was removed, and the effectiveness was evaluated according to the criteria of AO Yingfang. ResultsIn preservation group, the results were excellent in 34 cases, good in 22 cases, fair in 4 cases, and poor in 1 case;and in non preservation group, the results were excellent in 29 cases, good in 20 cases, fair in 10 cases, and poor in 2 cases;and there was no significant difference between 2 groups (Z=-1.320, P=0.187). ConclusionIn ACL reconstruction, the remnant-preserved technique is not obviously better than non remnant-preserved technique in the integrity, tension, membrane covering, and color.