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.
ObjectiveTo compare the effectiveness of open reduction of posterior cruciate ligament (PCL) avulsion fracture at tibial insertion of knee joint with absorbable screws fixation and absorbable screw combined with suture anchor fixation. Methods The clinical data of 26 patients with PCL avulsion fracture at tibial insertion who met the selection criteria between March 2015 and October 2021 were retrospectively analyzed. Among them, 14 patients were fixed with simple absorbable screw (group A), and 12 patients were fixed with absorbable screw combined with suture anchors (group B). All patients were confirmed by X-ray film, CT, or MRI preoperatively, and got positive results in preoperative posterior drawer tests. There was no significant difference in gender, age, side of affected limb, time from injury to operation, comorbidities, and preoperative Meyers & McKeever classification, Lysholm score, and International Knee Documentation Committee (IKDC) score between the two groups (P>0.05). The operation time and postoperative complications were recorded and compared between the two groups. At last follow-up, Lysholm score and IKDC score were used to evaluate the improvement of knee function. ResultsThere was no significant difference in operation time between the two groups (P>0.05). All incisions healed by first intention, and no complication such as vascular and nerve injury or venous thrombosis occurred. All 26 patients were followed up 9-89 months, with an average of 55.3 months. The follow-up time of group A and group B was (55.7±23.2) and (56.8±29.3) months, respectively, with no significant difference (t=−0.106, P=0.916). Radiographs showed bone healing in both groups at 3 months after operation, and no complication such as infection and traumatic arthritis occurred. At last follow-up, the posterior drawer test was negative in both groups, and the Lysholm score and IKDC score significantly improved when compared with the pre-operative values (P<0.05). However, there was no significant difference in the improvement value between the two groups (P>0.05). ConclusionFor PCL avulsion fracture at tibial insertion of the knee joint, the open reduction and absorbable screw combined with suture anchor fixation can achieve reliable fracture reduction and fixation, which is conducive to the early rehabilitation and functional exercise, and the postoperative functional recovery of the knee joint is satisfactory.
OBJECTIVE To measure the isometric point of the attachment site in femur during the reconstruction of posterior cruciate ligament (PCL). METHODS Seven fresh knee specimens from cadavers were adopted in this experiment. The anterior, posterior, proximal, distal and central points of the PCL’s femoral attachment site were respectively anchored to the middle of the PCL’s tibial attachment site by the trial isometer wires. The length changes of the intra-articular part of the wires were recorded while the knee was flexed from 0 degree to 120 degrees by a continuous passive motion(CPM) machine. RESULTS The maximal length changes in every points were compared. It showed that the length change in anterior point was the biggest, the distal point was less than that of anterior point, and the proximal point was the least. There was significant difference between proximal and posterior points, but no significant difference between proximal and central points, neither between central and posterior points. All of the maximal length changes of proximal, central and posterior points were not greater than 2 mm. CONCLUSION The femoral tunnel for the PCL reconstruction should be located at the proximal point, which is the middle point of upper edge of femoral attachment site. The selected point for femoral tunnel also may be moved slightly in the direction to central or posterior points according to the needs of operation.
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.