Objective To review the methods and progress of arthroscopic reconstruction of anterior cruciate l igament (ACL) with the remnant preservation technique. Methods Recent l iterature about arthroscopic reconstruction of ACL with the remnant preservation technique was reviewed and analyzed. Results The preserved ACL after injuries could be single-bundle or remnant. The preserved remnant provided synovium for the reconstructed ACL, and it could accelerate revascularization of the graft, and it was benefit for the proprioception too, and certain kinds of remnant could contribute to the stabil ity of the joint. The preserved remnant could prevent the washing-effect of the joint fluid, then prevent the enlargement of the tibial tunnel. Cyclops or impingement may occurred in remnant preservation technique. Conclusion Remnant preservation in ACL reconstruction can provide good cl inical result. But remnant preservation is a skill demanded technique. There should be more research and cl inical trials about remnant preservation in ACL reconstruction about its necessity and advantage, also disadvantage.
Objective To explore the biomechanic effects of multi ple freeze-thaw on human allograft tendons. Methods Thirty tendons (24 flexor digitorum superficial is tendons and 6 flexor poll icis longus tendons) were harvested from 3 fresh cadaver donors and were divided into 6 groups randomly (fresh group; 1 cycle, 2 cycle, 3 cycle, 5 cycle, and 10 cycle freeze-thaw groups). There was 4 flexor digitorum superficial is tendons and 1 flexor poll icis longus tendon in each group. The structural and mechanical properties as well as viscoelastic change were estimated. Results The results of the structural and mechanical properties in 1 cycle, 2 cycle, and 3 cycle freeze-thaw groups were similar to that of the fresh group (P gt;0.05). The tendons in 5 cycle and 10 cycle freeze-thaw groups showed a significantly lower ultimate load and maximum stress when compared with those of fresh group (P lt; 0.05), but there was no significant difference in maximum tensile or maximum strain (P gt; 0.05). Moreover, the tendons in 5 cycle and 10 cycle freeze-thaw groups had a significant increase in viscoelastic properties when compared with fresh group (P lt; 0.05). Conclusion In the cryopreservation of tendon allografts, the cycle of freeze-thaw should not exceed 3 times. Multiple cycle freeze-thaw will weaken the biomechanical properties of tendon allografts, which make grafts easier to fatigue or even rupture.
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 To investigate the outcomes of arthroscopic reduction and internal fixation of tibial eminence avulsion fracture using absorbable double suture anchors. Methods Between February 2007 and August 2009, 18 patients with tibial eminence avulsion fracture were treated with arthroscopic reduction and fixation using absorbable doublensuture anchors. There were 12 males and 6 females with an average age of 30.6 years (range, 17-48 years). The disease causes were traffic accident injury in 4 cases, sport injury in 8 cases, and fall ing from height injury in 6 cases; the locations were left side in 7 cases and right side in 11 cases. The results of the anterior drawer test and Lachman test were positive. According to Meyers-McKeever classification, 10 cases were rated as type II, 7 as type III, and 1 as type IV fractures. The time from injury to treatment was 6-20 days (mean, 10.2 days). Results Incision healed primarily. All the patients were followed up 29.1 months (range, 13-43 months). The X-ray films showed good reduction of fracture immediately after operation and fracture heal ing at 3 months. At the last follow-up, the range of motion of knee was 0-130°. The results of Lachman test and anterior drawer test were negative in 18 cases and 16 cases, repectively; and the results of anterior drawer test were weakly positive in 2 cases. The mean Lysholm score was significantly improved from 53.9 ± 6.7 preoperatively to 91.6 ± 4.2 postoperatively (t=22.100, P=0.000). The Inter national knee Documentation Commitee (IKDC) 2000 subject score improved from 58.1 ± 3.7 preoperatively to 92.8 ± 5.9 postoperatively (t=20.700, P=0.000). Conclusion Arthroscopic treatment using absorbable double suture anchors for tibial eminence avulsion fracture can provide satisfactory reduction, stable fixation, and good heal ing of the avulsed fragment, which is a minimally-invasive, simple, and effective treatment for patients with tibial eminence avulsion fracture.
Objective To investigate the effect of the anterior cruciate l igament (ACL) rupture on the biomechanics of the lateral collateral l igament (LCL). Methods The specimens in this experiment were knee joints from 6 normal fresh adult male cadavers which was donated voluntarily, aged of 26-35 years with an average of 31.4 years. The knee joints were dissymmetry with 3 in left and right sides respectively. At first, all the 6 specimens lying on the self-made movement tooting, whose LCL straining were measured by strain gauges at different angles (0, 30, 60 and 90°) under axial loads of 400 N by e-testing machine for simulation of the normal knee joint force, were regarded as the intact ACL group. Then, the ACL in all 6 specimens were cut off completely as the deficiency group and did the same step. Results The strain of the LCL were as follows at 0, 30, 60 and 90°: (0.00 ± 1.63), (—17.2 ± 8.57), (—24.00 ± 4.80) and (26.50 ± 4.65) με in intact ACL group; (0.75 ± 8.22), (— 52.75 ± 3.33), (24.30 ± 4.99) and (26.30 ± 4.27) με in deficiency group. There was no significant difference at 0° and 90° flexion (P gt; 0.05), but significant difference at 30° and 60° flexion (P lt; 0.05) between the two groups. Conclusion The rupture of the ACL has significantly effect on the strain of the LCL which suffering abnormal load in the state at 30° and 60° flexion. At 30° flexion the relaxation of the LCL increased, which means the possibil ity of the injury of the LCL is rare; and at 60° flexion the LCL become very tense and thereby at the high risk of instabil ity.
Objective To investigate the surgical technique and short-term effectiveness of anterior cruciate l igament (ACL) reconstruction with LARS artificial l igament. Methods Between November 2008 and April 2010, eighty patients withACL injury were treated with LARS artificial l igament under arthroscope and successfully followed up. There were 51 males and 29 females, aged from 17 to 43 years with an average of 29.2 years. The injuries were caused by sport in 63 cases, traffic accident in 14 cases, and bruise in 3 cases. There were 43 left knees and 37 right knees. The disease duration ranged from 10 days to 11 months. The anterior drawer test, Lachman test, and pivot shift test for all cases were rated as positive. The preoperative Lysholm score was 55.4 ± 5.7, Irgang score was 48.3 ± 6.2, and Larson score was 54.8 ± 7.4; and the International Knee Documentation Committee (IKDC) score was lower than normal level in all cases. Obl ique coronal MRI showed ACL injury in all cases. Residual ACL and synovium were preserved during surgery. Results All incisions healed by first intention without compl ication of infection or deep venous thrombosis. All patients were followed up 7 to 24 months with an average of 16.8 months. There were 3 cases of screws exposure toward femoral cortical bone, 2 cases of loosening tibial screw, and 1 case of knee extension l imitation, and they were cured after symptomatic treatment. No LARS artificial l igament rupture and joint fibrosis occurred during followup. At last follow-up, the results of anterior drawer test, Lachman test, and pivot shift test were positive in 2, 3, and 3 patients,respectively. There were significant differences in Lysholm, Irgang, and Larson scores of affected knees between preoperation and 6 weeks postoperatively, last follow-up, respectively (P lt; 0.05). The normal rate of IKDC score were 43.75% (35/80) and 97.50% (78/80) at 6 weeks postoperatively and last follow-up, respectively. Conclusion The viscoelastic properties of LARS artificial l igament is different from that of biological materials. The graft should be fixed at a relatively extension position to avoid knee extension l imitation and sl ight loosening of graft tension is permitted at flexion position. Good cl inical result could be achieved if the technique is well appl ied.
Objective To compare the effectiveness between arthroscopic double-bundle and single-bundle anterior cruciate l igament (ACL) reconstruction with deep-frozen allografts. Methods Between January 2008 and January 2009, 105 patients undergoing arthroscopic ACL reconstruction with deep-frozen allografts were selected and randomly divided intosingle-bundle (n=59) or double-bundle (n=46) groups. Patients were evaluated preoperatively and postoperatively 6, 12, and 24 months. Of the patients, 93 (51 in the single-bundle group and 42 in the double-bundle group) were available for full evaluation. There was no significant difference in gender, age, height, weight, disease duration, compl ication, the International Knee Documentation Committee (IKDC) score, and Lysholm score between 2 groups (P gt; 0.05). The anterior drawer test and the Lachman test for all were rated as + in 2 groups, and the pivot shift test were rated as ++ before operation. Results All wounds healed by first intention, and no related compl ication such as fracture, infection, or deep venous thrombosis was observed. There was no significant difference in the IKDC score, Lysholm score, anterior drawer test, pivot shift test, and Lachman test between 2 groups at 6-month and 12-month follow-up (P gt; 0.05). The IKDC score, Lysholm score, pivot shift test, Lachman test, and the side-to-side difference measured by KT-1000 arthrometer in the double-bundle group were significantly better than those in single-bundle group at 24-month follow-up (P lt; 0.05). Conclusion The double-bundle ACL reconstruction with deep-frozen allografts has better effectiveness than the single-bundle ACL reconstruction.
【Abstract】 Objective To introduce several navigation systems in anterior cruciate l igament reconstructionand to investigate the appl ication of navigation systems for the improvement in reconstruction of the anterior cruciatel igament. Methods The related l iterature was reviewed extensively, and the main current computer assisted surgery systems(OthoPilot system, Bone Morphing system, Fluoroscopic-based system, etc) for util ization in the anterior cruciate l igament reconstructionwere analyzed. Results The computer-assisted systems can enhance the accurate placement of tunnels. Accordingto the anatomical and isometric parameters, graft impingement on the intercondylar notch could be avoided, and individualideal implantation using 3D visual ization local isers was achieved. Conclusion It is possible that computer-assisted systemswill enable surgeons to better acquire the accuracy and rel iabil ity of the various operative techniques, to meet the demand ofsurgeon’s surgical optimisation and to improve the cl inical results.
Objective To investigate the effectiveness of percutaneous reduction by leverage and fixation using nonabsorbable suture with neckwear knot loop l igature to treat tibial intercondylar eminence avulsion fractures under the arthroscope. Methods Between February 2003 and December 2008, 28 patients with tibial intercondylar eminence avulsion fractures were treated, including 16 left knees and 12 right knees. There were 15 males and 13 females with an average age of19.5 years (range, 14-45 years). The injury causes included traffic accident injury in 11 cases, sport injury in 10 cases, and sprain injury in 7 cases. Based on Meyers-McKeever classification, there were 18 cases of type III and 10 cases of type IV. The X-ray films showed the tibial intercondylar eminence displaced fracture. The mean time between trauma and operation was 7 days (range, 4-12 days). All patients were treated surgically with an arthroscopically assisted reduction by leverage and fixation using 5-0 Ethibond suture with neckwear knot loop l igature. Results All incisions healed by first intention without infection or injuries of nerves and vessels. Twenty-eight patients were followed up 26 months on average (range, 12-66 months). The X-ray films showed fracture heal ing within 9-13 weeks (mean, 11 weeks). At last follow-up, all patients were able to return to their pre-injury activity and daily l ife. The knee joint was stable with no l imp or impingement of intercondylar fossa. The knee joint range of motion was 0-130°. The results of Lachman and anterior drawer tests were negative in all patients. At last follow-up, the Lysholm score was 93.5 ± 2.5, showing significant difference when compared with the preoperative one (29.0±2.2, t=53.000, P=0.000). Conclusion Percutaneous reduction by leverage and fixation using nonabsorbable suture with neckwear knot loop l igature is minimally invasive and satisfied reduction and fixation in treating the tibial intercondylar eminence avulsion fracture under the arthroscope, so it is benefit for early functional exercises, and can achieve excellent results.
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.