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 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 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 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 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.
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 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 compare the therapeutic effect of anterior cruciate l igament (ACL) reconstruction bymeans of four-strand semitendinosus tendon autograft and l igament advanced reinforcement system (LARS) by arthroscopy. Methods From July 2002 to April 2005, 42 patients underwent ACL reconstruction by arthroscopy. Twenty-seven patients were treated by four-strand semitendinosus tendon autograft (semitendinosus tendon autograft group), including 22 males and 5 females, with the age from 20 years to 52 years. Among these patients, there were 12 sports injuries, 8 traffic accidents and 7 other injuries. There were 16 cases of left knees and 11 of right knees. The pre-operation Lysholm score was 50.70 ± 6.68, and the course of the disease was 2 to 12 months. Other 15 patients were treated by LARS artificial l igament (LARS group), including 12 males and 3 females, with the age from 17 years to 40 years. Among these patients, there were 8 sports injuries, 4 traffic accidents and 3 other injuries. There were 6 cases of left knees and 9 of right knees. The pre-operation Lysholm score was 50.20 ± 6.22, and the course of the disease was 3 to 12 months. There was no statistically significant difference between the two groups (P gt; 0.05). The ranges of motion, stabil ity and compl ication of the knee were evaluated during the follow-up. Results All incisions healed at the first stage. The patients in the semitendinosus tendon autograft group were followed up for 22 months to 43 months, while 18 months to 40 months in the LARS group. There were 5 patients (19%) whose tensile gap was more than3 mm when the max tensile force text was done in the semitendinosus tendon autograft group, and 3 patients (20%) in the LARS group. The Lysholm score was 87.80 ± 3.41 in the semitendinosus tendon autograft autograft group, and 88.90 ± 3.30 in the LARS group. There was no statistically significant difference between the two groups (P gt; 0.05). The final evaluation based on the improved Lysholm classification standard showed the choiceness rate was 92.6% (18 excellent cases, 7 good cases and 2 faircases) in the semitendinosus tendon autograft group, and 93.3% (11 excellent cases, 3 good cases, 1 fair case) in the LARS group. There was no statistically significant difference between the two groups (P gt; 0.05). The joint motion capabil ity evaluation, according to the Tegner standard, showed 3 to 6 class (with the average class of 4.93) in the semitendinosus tendon autograft group, and 3 to 7 class (with the average class of 5.03) in the LARS group. There was no statistically significant difference (P gt; 0.05). The knee extension in 2 cases was 5° less than the normal, and in 5 cases 5-10° less than the normal in the semitendinosus tendon autograft group. But in all cases in the LARS group, joint motion recovered to the normal (P lt; 0.05). There was no sign of synovitis in both groups. Conclusion The recent cl inical result of ACL reconstruction with the four-strand semitendinosus tendon autograft or LARS artificial l igament by arthroscopy is satisfactory without significant difference. LARS can shorten the recovery time without compl ications such as synovitis in 2-year follow-up.
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.