Objective To explore the diagnosis and treatment of anterior cruciate l igament (ACL) cysts of the knees. Methods The cl inical data were retrospectively analysed from 13 patients with ACL cysts between December 2000 and August 2007. The patients included 7 males and 6 females with an average age of 46.3 years (range, 32-55 years). The locationswere the left knee in 6 cases and the right knee in 7 cases. Seven cases had an obvious history of trauma, 4 cases had a history of chronic injury, and 2 cases had no obvious incentive factor. The disease duration was from 6 to 29 months (mean, 20 months). Anterior drawer test was positive in 1 case, pivot shift test was positive in 1 case, and McMurray test was positive in 3 cases. Six cases were preoperatively diagnosed by MRI. The cysts located near the tibial insertion in 6 cases, between the ACL and the posterior cruciate l igament in 3 cases, and near the femoral attachment in 4 cases. All cysts were arthroscopically resected and had the pathohistological examination. Results The pathohistological examination showed mucoid degeneration of collagen and connective tissues, and the diagnosis result was ACL cyst. All incisions healed by first intention, and no compl ication occurred. Thirteen patients were followed up 2 to 5 years (mean, 2 years and 6 months). The symptoms of arthralgia, swell ing, and interlocking of the affected knees disappeared. At 24 months postoperatively, the anterior drawer test was positive in 1 case, the pivot shift test was positive in 1 case, and McMurray test was positive in 4 cases. There was no recurrence during the follow-up. There were significant differences in the range of motion and Lysholm score between pre- and post-operation (P lt; 0.01). Conclusion ACL cysts may be indicated by simple knee pain, especially when accompanied by l imitation of joint motion without imaging evidence of osteoarthritis. The MRI finding is very important in the diagnosis of ACL cysts, and arthroscopic resection and debridement is the first choice in the treatment of ACL cysts.
Objective To make a comparison for the change of maximum tensile intensity and stiffness of a whole implant that is placed into bone tunnel with various lengths tendon, by using beagle dog’s autogenous flexor tendons to reconstruct anterior cruciate l igament (ACL). Methods Sixty male beagle dogs were included in the experiment (weighting 13-16 kg). Three dogs were used for intact flexor tendon of both knees (normal control group), 3 dogs for the intact ACL andfemur-graft-tibia complex (auto control group) and 54 dogs (108 knees) for models of reconstructed ACL (6 experimentalgroups according to different lengths of tendon: 5, 9, 13, 17, 21 and 25 mm in the bone tunnel). The tensile intensity and stiffness were measured after 45, 90 and 180 days separately after operation. Results In the normal control group, the maximum tensile intensity of the intact flexor tendon was (564.15 ± 36.18) N, the stiffness was (59.89 ± 4.28) N/ mm. In the auto control group, the maximum tensile intensity of the intact ACL was (684.75 ± 48.10) N, the stiffness was (74.34 ± 6.99) N/ mm, all ruptured through the intra-articular portion of the graft. The maximum tensile intensity of femur-graft-tibia complex in the auto control group was (301.92 ± 15.04) N, the stiffness was (31.35 ± 1.97) N/mm. After 45 days of operation, all failure occurred at the tibial or femoral insertion site. After 90 days of operation, 24 of the breakpoints were scattered in tendon-bone junction, 12 (3 in 17 mm group, 5 in 21 mm group, 4 in 25 mm group) ruptured through the intra-articular portion. After 180 days of the operation, all breakpoints were distributed inside joint of the implant. The maximum tensile intensity and the stiffness were ber in 17, 21 and 25 mm groups than in 5, 9 and 13 mm groups after operation (P lt; 0.05). Conclusion Tendon with 17 mm length, which will be implanted into bone tunnel, is an appl icable index, in reconstruction of ACL by autogenous tendons.
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 review the studies about the tibial-graft fixation methods on anterior cruciate ligament (ACL) reconstruction, in order to provide clinical reference. MethodsThe literature about the tibial-graft fixation methods on ACL reconstruction at home and abroad was extensively reviewed, and the factors that affect the selection of fixation methods were summarized. Results The knee flexion angle, graft tension, and graft fixation device are mainly considered when the tibial-graft was fixed on ACL reconstruction. At present, the graft is mainly fixed at 0°/30° of knee flexion. The study shows that the knee joint is more stable after fixed at 30°, while the incidence of knee extension limitation decrease after fixed at 0°. In terms of graft tension, a good effectiveness can be obtained when the tension level is close to 90 N or the knee flexion is 30° to recover the affected knee over-restrained 2 mm relative to the healthy knee. In terms of the graft device, the interference screw is still the most commonly used method of tibial-graft fixation, with the development of all-inside ACL reconstruction in recent years, the cortical button fixation may become the mainstream. Conclusion Arthroscopic reconstruction is the main treatment of ACL rupture at present. However, there is no optimal fixation method for the tibial-graft, the advantages and disadvantages of each fixation methods need to be further studied.
Objective To investigate the effect of acid, basic fibroblast growth factor (aFGF, bFGF) and epidermal growth factor (EGF), andtheir combination on the proliferation of rabbit anterior cruciate ligament (ACL) and medial collateral ligament (MCL) in vitro. Methods Thecells of ACL and MCL were isolated and subcultured from the knee joints of tenweek-old New Zealand white rabbits. The cells were seeded into 96-well corning cluster plates. Three growth factors of different concentration alone or in combination were added into the culture medium respectively, which were 0, 1, 5, 10, 50 and 100 ng/ml for aFGF, bFGF and 0, 1.56, 3.13, 6.25, 12.5, 25 and 50 ng/ml for EGF. The proliferation of the fibroblasts was measured for 48 h with XTT method. Results All of the three growth factors alone promoted the cell proliferation of ACL and MCL fibroblasts. The concentration of aFGF hada significant effect on the proliferation of both ACL and MCL fibroblasts. The concentration of 1 ng/ml bFGF and 5 ng/ml EGF was most effective in promoting the proliferation of ACL, and both bFGF and EGF had a significant effect on MCL. 5ng/ml aFGF with 50 ng/ml EGF had effect on ACL. 1 ng/ml aFGF with 3.13 ng/ml EGF had effect on MCL. Conclusion The three growth factors may promote the cell proliferation of ACL and MCL. These findings suggest that topical application of aFGF, either alone or in combination with EGF may have the potential to promote the proliferation of rabbit ACL and MCL,and aFGF of low concentration in combination with EGF is more effective than single growth factor.
Objective To investigate the effectiveness of slope-reducing tibial osteotomy and anterior cruciate ligament (ACL) revision in the treatment of patients with primary ACL reconstruction failure and abnormally increased posterior tibial slope (PTS). Methods The clinical data of 9 patients with primary ACL reconstruction failure and abnormally increased PTS (≥17°) who met the selection criteria between January 2018 and January 2020 were retrospectively analyzed. There were 8 males and 1 female; the age ranged from 21 to 42 years, with a median age of 30 years. Lachman test was positive in 9 patients. Pivot-shift test was negative in 6 cases, degree Ⅰ positive in 2 cases, and degree Ⅱ positive in 1 case. The PTS was (17.78±1.09)° and the anterior tibial translation (ATT) was (11.58±1.47) mm. The International Knee Documentation Committee (IKDC) score was 51.0±3.8, Lysholm score was 49.7±4.6, and Tegner score was 3.7±0.7. The time from primary reconstruction to revision was 12-33 months, with an average of 19.6 months. Slope-reducing tibial osteotomy and ACL revision were performed. The improvement of knee function was evaluated by IKDC score, Lysholm score, and Tegner score; Lachman test and Pivot-shift test were used to evaluate the stability of knee joint. PTS and ATT were measured to observe the morphological changes of knee joint. Results All the incisions healed by first intention, and there was no complication such as incision infection, fat liquefaction, necrosis, deep vein thrombosis of lower extremities, and neurovascular injury. All 9 patients were followed up 12-36 months, with an average of 25.8 months. At last follow-up, Lachman test and pivot-shift test were negative. IKDC score was 85.0±4.0, Lysholm score was 87.7±2.8, Tegner score was 6.8±0.7, PTS reduced to (9.89±0.60)°, and ATT shortened to (0.91±0.29) mm, which were significantly improved when compared with those before operation (P<0.05). ConclusionSlope-reducing tibial osteotomy and ACL revision in the treatment of patients with primary ACL reconstruction failure and abnormally increased PTS has a satisfactory short-term effectiveness. It can improve the stability of knee joint and maintain the normal shape of knee joint.
Objective To explore the best flexion angle of the transplantation tendon for fixing joint in simultaneously reconstructing of the anterior cruciate l igament (ACL) and posterior cruciate l igament (PCL) using semitendinosus tendon as autologous graft. Methods Twenty-four clean level New Zealand White rabbits [(aged 6-8 months, male or female, and weighing (2.5 ± 0.2) kg] were selected and divided randomly into 3 groups (n=8) according to fixation angle of the reconstructed l igaments. The bilateral semitendinosus tendons of hind legs were used to reconstruct the PCL and ACL of right hind leg, and the reconstructed l igaments were fixed at knee flexion angles of 90° (group A), 60° (group B), and 30° (group A). The rabbit general situation was observed after operation, and the specimens of the knee joints (including 10 cmdistal end and 10 cm proximal end) were harvested for testing extension and flexion, displacement, and internal and external rotation at 3 months after operation. Results All the rabbits survived to the end of experiment. There was no significant difference in maximal displacements of ACL and PCL among 3 groups (P gt; 0.05). The anterior and posterior displacements of shift in 3 groups were less than 1 mm, suggesting good stabil ity. The anterior displacement and the posterior displacement at 30° flexion and 90° flexion in group A were significantly larger than those in group C (P lt; 0.05). There were significant differences in internal rotation angle and external rotation angle between group A and group C (P lt; 0.05), and there was no significant difference among other groups (P gt; 0.05). Conclusion When simultaneously reconstructing ACL and PCL, the knee flexion angle of 60° for fixing the reconstructed l igaments can achieve the best effect.
Objective To compare the effectiveness of anatomical single-bundle (ASB) and over-the-top singlebundle (OSB) reconstruction of the anterior cruciate l igament (ACL). Methods Between January 2008 and June 2008, 64 patients with ACL injury underwent arthroscopic ACL reconstruction. ASB ACL reconstruction was performed in 28 cases (ASB group) and OSB ACL reconstruction in 36 cases (OSB group). There was no significant difference in gender, age, diseaseduration, International Knee Documentation Committee (IKDC) score, Lysholm score, and side-to-side difference between 2 groups (P gt; 0.05). Results All incisions healed by first intention; no infection or other compl ications occurred. All cases were followed up 20-24 months (mean, 21.5 months). There were significant differences in the IKDC score, Lysholm score, and the side-to-side difference between last follow-up and preoperation in 2 groups (P lt; 0.05), but there was no significant difference between 2 groups at last follow-up (P gt; 0.05). Significant differences were found in negative rate of the pivot shift test between last follow-up and preoperation in ASB group and between 2 groups at last follow-up (P lt; 0.05), but there was no significant difference between last follow-up and preoperation in OSB group (P gt; 0.05). Conclusion The effectiveness of arthroscopic ASB ACL reconstruction is better than that of arthroscopic OSB ACL reconstruction, especially in controll ing rotational stabil ity.