Objective To investigate the effect of Kartogenin (KGN) combined with adipose-derived stem cells (ADSCs) on tendon-bone healing after anterior cruciate ligament (ACL) reconstruction in rabbits. Methods After the primary ADSCs were cultured by passaging, the 3rd generation cells were cultured with 10 μmol/L KGN solution for 72 hours. The supernatant of KGN-ADSCs was harvested and mixed with fibrin glue at a ratio of 1∶1; the 3rd generation ADSCs were mixed with fibrin glue as a control. Eighty adult New Zealand white rabbits were taken and randomly divided into 4 groups: saline group (group A), ADSCs group (group B), KGN-ADSCs group (group C), and sham-operated group (group D). After the ACL reconstruction model was prepared in groups A-C, the saline, the mixture of ADSCs and fibrin glue, and the mixture of supernatant of KGN-ADSCs and fibrin glue were injected into the tendon-bone interface and tendon gap, respectively. ACL was only exposed without other treatment in group D. The general conditions of the animals were observed after operation. At 6 and 12 weeks, the tendon-bone interface tissues and ACL specimens were taken and the tendon-bone healing was observed by HE staining, c-Jun N-terminal kinase (JNK) immunohistochemical staining, and TUNEL apoptosis assay. The fibroblasts were counted, and the positive expression rate of JNK protein and apoptosis index (AI) were measured. At the same time point, the tensile strength test was performed to measure the maximum load and the maximum tensile distance to observe the biomechanical properties. Results Twenty-eight rabbits were excluded from the study due to incision infection or death, and finally 12, 12, 12, and 16 rabbits in groups A-D were included in the study, respectively. After operation, the tendon-bone interface of groups A and B healed poorly, while group C healed well. At 6 and 12 weeks, the number of fibroblasts and positive expression rate of JNK protein in group C were significantly higher than those of groups A, B, and D (P<0.05). Compared with 6 weeks, the number of fibroblasts gradually decreased and the positive expression rate of JNK protein and AI decreased in group C at 12 weeks after operation, with significant differences (P<0.05). Biomechanical tests showed that the maximum loads at 6 and 12 weeks after operation in group C were higher than in groups A and B, but lower than those in group D, while the maximum tensile distance results were opposite, but the differences between groups were significant (P<0.05). Conclusion After ACL reconstruction, local injection of a mixture of KGN-ADSCs and fibrin glue can promote the tendon-bone healing and enhance the mechanical strength and tensile resistance of the tendon-bone interface.
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.
ObjectiveTo summarize the relationship between lateral femoral notch sign (LFNS) and anterior cruciate ligament (ACL) rupture. MethodsThe relevant literature of LFNS at home and abroad in recent years was retrospectively reviewed, and its mechanism, diagnostic criteria and influencing factors in diagnosis of ACL rupture were summarized and analyzed.ResultsThe LFNS is associated with rotational stability of the knee. As an indirect sign of ACL rupture, the LFNS has high clinical diagnostic value, especially the diagnosis of ACL rupture with lateral meniscus injury.ConclusionThe diagnostic criteria and influencing factors of LFNS in diagnosis of ACL rupture are still unclear and controversial, which needs further study.
Objective To review the research progress of internal tension relieving technique in assisting anterior cruciate ligament (ACL) reconstruction with tendon grafts. MethodsThe in vivo and in vitro biomechanical tests, animal experiments, and clinical studies on the use of internal tensioning relieving technique assisted ACL reconstruction in recent years were extensively reviewed, the impact of this technology on the biomechanics, histological changes of grafts, and the clinical effectiveness were analyzed and summarized. Results The internal tensioning relieving technique based on non-absorbable high-strength sutures can reduce the risk of relaxation and rupture by enhancing the biomechanical strength of tendon grafts in vitro and in vivo, it shows good biocompatibility and support for the ligamentation of the tendon grafts and the establishment of the direct tendon-bone interface in terms of histology. This technique improves postoperative initial joint stability, range of motion, and functional scores in clinical practic, when combining with the enhanced recovery after surgery can effectively promote patients to return to pre-injury exercise level without serious complications. Conclusion The preliminary research results have confirmed the efficacy and safety of the internal tension relieving technique on assisting ACL reconstruction, then showes some degree of significance and prospect, but more research is needed to further optimize tension-relieving devices and related surgical techniques, and clarify the specific effects of this technique on graft’s structure remodeling, biomechanical function, and long-term clinical results.
The anterior cruciate ligament (ACL) reconstruction mostly relies on the experience of surgeons. To improve the effectiveness and adaptability of the tension after ACL reconstruction in knee joint rehabilitation, this paper establishes a lateral force measurement model with relaxation characteristics and designs an on-line stiffness measurement system of ACL. In this paper, we selected 20 sheep knee joints as experimental material for the knee joint stability test before the ACL reconstruction operation, which were divided into two groups for a comparative test of single-bundle ACL reconstruction through the anterolateral approach. The first group of surgeons carried out intraoperative detection with routine procedures. The second group used ACL on-line stiffness measurement system for intraoperative detection. After that, the above two groups were tested for postoperative stability. The study results show that the tension accuracy is (− 2.3 ± 0.04)%, and the displacement error is (1.5 ± 1.8)%. The forward stability, internal rotation stability, and external rotation stability of the two groups were better than those before operation (P < 0.05). But the data of the group using the system were closer to the preoperative knee joint measurement index, and there was no significant difference between them (P > 0.05). The system established in this paper is expected to help clinicians judge the ACL reconstruction tension in the operation process and effectively improve the surgical effect.
Objective Anterior cruciate ligament (ACL) reconstruction using a new generation of artificial ligaments (NGAL) gained popularity in China owing to its good effectiveness and early functional recovery, but iatrogenic surgical failures and preconceived misconceptions have seriously affected its standardized clinical application. A specialist consensus is now developed to provide guidance and reference for orthopaedic sports medicine doctors when adopting or considering the NGAL for ACL reconstruction. Methods The consensus on the core techniques and adverse events in ACL reconstruction using the NGAL was developed by a modified Delphi method, referring exclusively to the NGAL for ACL reconstruction approved by the National Medical Products Administration (NMPA). Consensus specialists were selected from the members of the Chinese Association of Orthopaedic Surgeons (CAOS) and the Chinese Society of Sports Medicine (CSSM). The drafting team summarized the draft consensus terms based on medical evidence and organized rounds of investigation: two rounds of online questionnaire investigation and the final round of face-to-face meeting. After discussion, revision, and voting, a consensus on the draft consensus term was reached when the agreement rate exceeded 85%. The consensus terms were categorized as “strong” (agreement rate: 95.0%-100%), “moderate” (agreement rate: 90.0%-94.9%), and “basic” (agreement rate: 85.0%-89.9%). ResultsThirty-one specialists completed the questionnaire investigation. They all practiced in university teaching hospitals (Grade-A tertiary hospitals) from 16 provinces, autonomous regions, and municipalities in China. Among them, 28 were chief physicians and 3 were associate chief physicians; 22 were professors and 7 were associate professors; the average seniority in orthopedic sports medicine was 25.2 years (range, 12-40 years); the average seniority in performing ACL reconstruction procedures was 13.2 years (range, 7-23 years); in terms of the number of ACL reconstruction using the NGAL, 18 completed more than 100 cases, of which 6 had more than 300 cases; in terms of research, 28 had published more than 1 related paper in the past 5 years, of which 13 had published more than 3 related papers. Twenty-six specialists attended the face-to-face meeting and reached a consensus on 9 terms, including 8 strong terms and 1 moderate term. Conclusion ACL reconstruction using the NGAL must deploy “isometric” or “near-isometric” reconstruction and should preserve the natural ACL remnants as much as possible. Bone tunnel positioning can be performed using intraoperative radiographic measurements or the lateral femoral intercondylar ridge as reference marks. Incorrect positioning of the bone tunnel is the main reason of surgical failure, and there is a lack of consensus on handling interference screws during revision. Bone tunnel enlargement exists after reconstruction but rarely causes related symptoms. Synovitis and infection are uncommon complications. The aging effect of polyethylene terephthalate fiber on the long-term clinical outcomes is unknown and deserves attention.
ObjectiveTo investigate the risk factors of contralateral anterior cruciate ligament (ACL) injury after primary ACL reconstruction. Methods A retrospective review was conducted on the 716 patients with ACL injury who received primary ACL reconstruction surgery and met the selection criteria between January 2012 and September 2018. After a mean follow-up period of 7.6 years (range, 4-10 years), 65 patients (9.1%) experienced contralateral ACL injury (injured group) and 651 patients (90.9%) did not (uninjured group). There was no significant difference in age, body mass index, and preoperative Lachman test degree between groups (P>0.05). However, the proportion of female in the injured group was significantly higher than that of male (P<0.05), and the preoperative posterior tibial slope (PTS) was significantly higher than that of the uninjured group (P<0.05). Using the outcome of contralateral ACL injury as the dependent variable, the clinical data of the patient was first used as the independent variable, and univariate COX regression was used to analyze the prognostic influencing factors. Then, the indicators with differences in univariate COX regression were used as the independent variable, and multivariate COX regression was used to analyze the independent risk factors affecting prognosis. Log-Rank (Mantel-Cox) test was used to test and analyze the occurrence time of contralateral ACL injury in patients of different genders; X-tile software was used to analyze the occurrence time of contralateral ACL injury in patients with different PTS using Log-Rank (Mantel-Cox) test and PTS cut-off values. ResultsUnivariate COX regression analysis showed that gender and PTS were influence factors for contralateral ACL injury (P<0.05); further multivariate COX regression analysis showed that female and increased PTS were independent risk factors for contralateral ACL injury (P<0.05). The Log-Rank (Mantel-Cox) test results showed that the contralateral ACL injury occurred in female at 8.853 (8.600, 9.106) years, which was significantly shorter than that in male [9.661 (9.503, 9.819) years] (χ2=20.323, P<0.001). Using X-tile software to analyze the cut-off value of PTS, it was found that the cut-off value of PTS for contralateral ACL injury was 10.92°. According to the Log-Rank (Mantel-Cox) test, it was found that the contralateral ACL injury occurred in 5.762 (4.981, 6.543) years in patients with PTS≥10.92°, which was significantly shorter than patients with PTS<10.92° [9.751 (9.650, 9.853) years](χ2=302.479, P<0.001). ConclusionFemale and PTS≥10.92° after primary ACL reconstruction are independent risk factors for contralateral ACL injury.
Objective To explore effectiveness of suture-bridge fixation under arthroscopy in treatment of tibial eminence avulsion fracture of anterior cruciate ligament in adolescents. Methods Between June 2013 and October 2016, 18 adolescent patients suffered from tibial eminence avulsion fracture of anterior cruciate ligament were treated by suture-bridge fixation under arthroscopy. There were 11 males and 7 females with an average age of 12.5 years (range, 5-17 years). The injury caused by bruise in 6 cases, by sprain in 4 cases, and by sport injury in 8 cases. The interval between injury and admission ranged from 2 hours to 10 months (median, 2 months). The results of preoperative Lachman and anterior drawer tests were positive. There were 10 cases of knee pain, 4 cases of knee extension limitation, and 4 cases of knee extension without strength. According to the Meyer-McKeever classification criteria, 12 cases were type Ⅱ and 6 cases were type Ⅲ. Results All incisions healed by first intention. All 18 patients were followed up 10-18 months after operation, with an average of 12 months. Postoperative X-ray films showed that all fractures healed after 6-12 weeks (mean, 8 weeks). The results of postoperative Lachman and anterior drawer tests were negative. At last follow-up, the Lysholm knee score was 90.1±5.0 and 93.1±6.2 for affected and unaffected sides, respectively, showing no signifi cant difference (t=0.669, P=0.184). There was no premature closure of skeleton or leg length discrepancy deformity. Conclusion For tibial eminence avulsion fracture of anterior cruciate ligament in adolescents, the suture-bridge fixation under arthroscopy is an effective method with many advantages, such as minimal invasion, reliable fixation, good fracture healing, and no need for second operation to remove implants.
The application of artificial ligament products in anterior cruciate ligament (ACL) surgeries has gone through a long twisty way. In the 1970s, early artificial ligament products were initially used for ACL surgeries, which showed poor clinical efficacy and eventually ended up in failure. Over the last 20 years, there has been a growing number of ACL reconstruction with new artificial ligament products, including the Leeds-KeioTM, the LARSTM (Ligament Advanced Reinfocement System), and the Trevira HochfestTM. Among these new products, the LARSTM has been more commonly applied for ACL surgeries. Although these new artificial ligament products have good mechanical properties and show significant improvement of cumulative failure and complication rate, they still have limitations.
Objective To investigate the effectiveness of anterior cruciate ligament (ACL) reconstruction assisted by personalized femoral locator based on the apex of deep cartilage (ADC) combined with patient imaging data. Methods Between January 2021 and January 2022, a total of 40 patients with primary ACL rupture were selected and randomly divided into study group (ACL reconstruction assisted by personalized femoral locator based on ADC) and control group (ACL reconstruction assisted by intraoperative fluoroscopy and traditional femoral locator), with 20 cases in each group. There was no significant difference in gender, age, body mass index, affected side, cause of injury, and preoperative International Knee Documentation Committee (IKDC) score, Lyshlom score, and Tegner score between the two groups (P>0.05). IKDC score, Lyshlom score, and Tegner score were used to evaluate the functional recovery of the affected knee before operation and at 3, 6, and 12 months after operation. CT scan and three-dimensional reconstruction were performed before and after operation to measure the horizontal distance from ADC to the anterior cartilage margin (L) and the horizontal distance from ADC to the center of the femoral canal (I), and the anteroposterior position of the bone canal (R) was calculated by I/L; the distance from the center to the distal cartilage margin (D) was measured on the two-dimensional cross section; the R value and D value were compared between the two groups. Results The operation time of the study group was significantly less than that of the control group [MD=−6.90 (−8.78, −5.03), P<0.001]. The incisions of the two groups healed by first intention, and no complication such as intra-articular infection, nerve injury, and deep vein thrombosis of lower limbs occurred. There was no significant difference in the R value and D value between the preoperative simulated positioning and the actual intraoperative positioning in the study group [MD=0.52 (−2.85, 3.88), P=0.758; MD=0.36 (−0.39, 1.11), P=0.351]. There was no significant difference in the actual intraoperative positioning R value and D value between the study group and the control group [MD=1.01 (−2.57, 4.58), P=0.573; MD=0.24 (−0.34, 0.82), P=0.411]. The patients in both groups were followed up 12-13 months (mean, 12.4 months). The IKDC score, Lysholm score, and Tegner score of the two groups increased gradually with time, and there were significant differences between pre- and post-operation (P<0.05). There was no significant difference in the scores between the two groups at each time point after operation (P>0.05). Conclusion The personalized femoral locator based on ADC can accurately assist the femoral tunnel positioning in ACL reconstruction, which can shorten the operation time when compared with traditional surgical methods, and achieve satisfactory early effectiveness.