study of anatomical location of the low tibial tunnel in posterior cruciate ligament reconstruction based on CT images北大核心CSCD

Objective To measure the anatomical parameters of the simulated low tibial tunnel of posterior cruciate ligament (PCL) based on knee CT images so as to provide clinical reference for accurate location of the tunnel. Methods The CT images of 201 healthy knee joints collected at Department of Orthopedics, The Second Hospital of Lanzhou University from June 2016 to September 2021 were used for simulation of the PCL low tibial tunnel. The anatomical parameters of the tibial tunnel were measured using the RadiAnt DICOM Viewer. The primary measures included the angle between tibial plateau and tibial tunnel (ATPT) and the perpendicular distances from the tibial tunnel entrance and exit point to the tibial plateau (L1 and L2). The secondary measures included the angle between tibial plateau and posterior slope (PSA), the angle between tibial anatomical axis and central line of tibial tunnel (ATAA), the angle between posterior tibial slope line and the central line of tibial tunnel (APST), the anterior and posterior diameter of tibial plateau (APD), the length of posterior tibial slope (LPTS), and the length of tibial tunnel (LTT). The measurement results were analyzed according to the body height (divided into 3 groups: a 1.00 to 1.60 m group, a 1.61 to 1.70 m group, and a ≥1.71 m group) and gender using the software IBM SPSS 26. Results The primary measures: ATPT was 37.0°±4.5°, and L1 and L2 were respectively (57.8±7.4) mm and (34.5±3.3) mm. The secondary measures: PSA 128.1°±5.4°, ATAA 52.7°±4.1°, APST 89.1°±5.9°, APD was (32.9±2.6) mm, LPTS (20.5±2.4) mm, and LTT (40.9±5.7) mm. After grouping by gender, there was no significant difference in PSA between men and women (P>0.05) while there were significant differences in the other indexes between men and women (P<0.05). After grouping by body height, there was no significant difference in ATPT, PSA, APST or ATAA between the 3 groups (1.00 to 1.60 m group, 1.61 to 1.70 m group and ≥1.71 m group) (P>0.05) while there were significant differences in L1, L2, APD, LPTS and LTT between the 3 groups (P<0.05). Conclusions Based on the knee CT images, the primary measures of PCL low tibial tunnel are as follows: the angle between tibial plateau and tibial tunnel is 37.0°±4.5°, and the perpendicular distances from the tibial tunnel entrance and exit point to the tibial plateau are (57.8±7.4) mm and (34.5±3.3) mm, respectively. Gender and body height are the important factors influencing the above measurement outcomes. © 2022 Chinese Journal of Orthopaedic Trauma. All rights reserved.     

异体胫前肌腱"Y"形双束双隧道重建后十字韧带的疗效分析

Objective To investigate the clinical results of posterior cruciate ligament (PCL) reconstruction by double bundle-double tunnel Y-shape of the anterior tibialis tendon allograft. Methods From March 2001 to January 2008, 47 patients underwent PCL reconstruction were included. The allogeneic adult anterior tibialis tendon was prepared into the Y-shape double bundles with the length of 130 mm; A bundle was defined as A-side; B-side was two short bundle (B1, B2 bundle). A bundle was 70 mm in length with a diameter of 10-12 mm. B1 bundle (anterolateral bundle) was 55 mm long with a diameter of 6 mm; B2 bundle(posteromedial bundle) was about 50 mm with a diameter of 6 mm. The allograft ligament was installed through the antero-medial approach. Absorbable interface screws were fixed in the tibial tunnel firstly, and then in the femoral tundles. When being fixed, anterolateral bundle was in flexion of 90°, postero-medial bundle was in 30°. Assisted exercise with knee an angle-locked walking aid had continued for 8-10 weeks. Results The average operating time were 45 min. The average follow-up time was 49.5 months. Preoperative Lachmann was positive in all cases while Lachmann was negative in 39 cases, weakly positive in 5 cases, and positive in 4 cases postoperatively. Post-operative KT-1000 testing, Lysholm score and Tegner activity levels has improved significantly compare with the pre-operative ones. Conclusion The double folded bundles of adult anterior tibialis tendon has sufficient length and diameter for posterior cruciate ligament reconstruction with power tension. The methods of ligament passing through the tunnel has improved to ease the procedure.     

异体胫前肌腱"Y"形双束双隧道重建后十字韧带的疗效分析

Objective To investigate the clinical results of posterior cruciate ligament (PCL) reconstruction by double bundle-double tunnel Y-shape of the anterior tibialis tendon allograft. Methods From March 2001 to January 2008, 47 patients underwent PCL reconstruction were included. The allogeneic adult anterior tibialis tendon was prepared into the Y-shape double bundles with the length of 130 mm; A bundle was defined as A-side; B-side was two short bundle (B1, B2 bundle). A bundle was 70 mm in length with a diameter of 10-12 mm. B1 bundle (anterolateral bundle) was 55 mm long with a diameter of 6 mm; B2 bundle(posteromedial bundle) was about 50 mm with a diameter of 6 mm. The allograft ligament was installed through the antero-medial approach. Absorbable interface screws were fixed in the tibial tunnel firstly, and then in the femoral tundles. When being fixed, anterolateral bundle was in flexion of 90°, postero-medial bundle was in 30°. Assisted exercise with knee an angle-locked walking aid had continued for 8-10 weeks. Results The average operating time were 45 min. The average follow-up time was 49.5 months. Preoperative Lachmann was positive in all cases while Lachmann was negative in 39 cases, weakly positive in 5 cases, and positive in 4 cases postoperatively. Post-operative KT-1000 testing, Lysholm score and Tegner activity levels has improved significantly compare with the pre-operative ones. Conclusion The double folded bundles of adult anterior tibialis tendon has sufficient length and diameter for posterior cruciate ligament reconstruction with power tension. The methods of ligament passing through the tunnel has improved to ease the procedure.     

Concurrent arthroscopic bicruciate ligament reconstruction using Achilles tendon-bone allografts: experience with 15 cases

Objective： To evaluate the clinical outcome of arthroscopically assisted combined anterior and posterior cruciate ligament （ACL/PCL） reconstructions using Achilles tendon-bone allografts.
Methods： Associated meniscus injuries were treated according to established methods prior to ligament reconstructions during arthroscopic surgery. Thirty Achilles tendon-bone allografts were used to reconstruct torn ACL and PCL in 15 knees. At postoperative follow-up, all knees were graded using the modified IKDC and the Lysholm scoring systems just as done preoperatively. Results were analyzed compared with the contralateral healthy knees.
Results： Eleven men and 4 women with a minimum of 3-year follow-up （mean 38 months） were included in the study. Preoperatively, the group ratings by the modified IKDC standards were all severely abnormal. Twelvebicruciate reconstructions were performed in subacute or chronic stage （〉3-8 weeks）, 3 for acute ligamentous deficiencies （≤ 3 weeks）. The noticeable early complication was transitory local fever combined with joint effusion in one case. At postoperative follow-up, 9 knees were normal, 5 nearly normal and 1 abnormal. On Lysholm score the difference was statistically significant （ttest, P〈0.001） before and after operation. Conclusions： Achilles tendon-bone allograft offers an alternative for simultaneous arthroscopic ACL/PCL reconstructions. However, further investigation is needed to eradicate its potential immunogenicity for better use.     

Akagi胫骨前后轴在全膝关节置换术中的定位作用

Objective To investigate the relationship between tibial anteroposterior axis and other anatomic landmarks in determining the rotation of tibial prosthesis in total knee arthroplasty using computed tomography. Methods Transverse CT scans of 40 volunteers' right knee in full extension were made. The anteroposterior axis of the tibia was defined as a line which was perpendicular to the transepicondylar axis and passing through the middle point of the posterior crnciate ligament. At the tibial plateau and optimum re-section level, the mean medial percentage width of intersection point of the patellar tendon anti the antero-posterior axis was measured. The mean angle between the anteroposterior axis and a line connecting the middle of the posterior cruciate ligament and the medial of the patellar tendon and the medial 1/3 of the patellar tendon were measured. Results At the tibial plateau level, the mean medial percentage width of intersection point of the patellar tendon was 10.1%±8.3%. At the optimum resection level, the mean medial percentage width of intersection point of the patellar tendon was 0.2%±10.0%. At the optimum resection lev-el, the mean angle between the anteroposterior axis and a line connecting the middle of the posterior cruciate ligament and the medial of the patellar tendon was 0.1°±2.7°. The mean angle between the anteroposterior axis and a line connecting the middle of the posterior cruciate ligament anti the medial 1/3 of the patellar tendon was 10.3°±3.6°. Conclusion There was a tendency to align the tibial component in external rotation relative to the femoral component when the medial 1/3 of the patellar tendon was used. The line connecting the middle of the posterior cruciate ligament and the medial of the patellar tendon can be used as a reliable axis for correct rotational orientation of the tibial component.     

Multiple-ligament injured knee

Objective: To explore the clinical characteristic of the multiple-ligament injured knee and evaluate the protocol, technique and outcome of treatment for the multipleligament injured knee. Methods: From October 2001 to March 2005, 9 knees with combined anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) tears in 9 patients were identified with clinical and arthroscopic examinations. Of them, 5 knees were combined with ruptures of posteromedial corner (PMC) and medial collateral ligament (MCL), 4 with disruptions of posterolateral corner (PLC), 2 with popliteal vascular injuries and 1 with peroneal nerve injuries. Six patients were hospitalized in acute phase of trauma,2 received repairs of popliteal artery and 4 had repairs of PMC and MCL. Reconstructions of ACL and PCL with autografts under arthroscope were performed in all patients at 4 to 10 weeks after trauma, including reconstruction of PLC with the posterior half of biceps femoris tendon tenodesis in 4 patients and reconstructions of PMC and MCL with femoral fascia in 1 patient. Results: No severe complications occurred at early stage after operation in the 9 patients. All of them were followed up for 10-39 months with an average of 23. 00 months±9. 46 months. Lysholm score was 70-95 with an average of 85.00±8.29. International Knee Documentation Committee (IKDC) score was from severely abnormal (Grade D) in 9 knees at initial examination to normal (Grade A) in 2 knees, nearly normal (Grade B) in 6 knees and abnormal in 1 knee at the last follow-up. Of the 9 patients, 7 returned to the same activity level before injury and 2 were under the level. Conclusions:The multiple-ligament injured knee with severe instability is usually combined with other important structure damages. Therefore, careful assessment and treatment of the combined injuries are essential. Reconstructions of ACL and PCL under arthroscope, combined with repairs or reconstructions of the extraarticular ligaments simultaneously or in stages, have advantage of minimal trauma in surgery and satisfactory outcome.     

全关节镜下膝关节后外复合体重建

目的 介绍全关节镜下腘肌腱重建、腘肌腱联合腘腓韧带重建或膝关节后外复合体(posterolateral corner,PLC)解剖重建的手术技术,探讨全关节镜下PLC重建治疗膝关节后外不稳定的效果.方法 2008年8月至2010年4月,共完成全关节镜下后十字韧带(posterior cruciate ligament,PCL)+PLC重建手术34例.患者在接受手术时平均年龄34.1岁(15～52岁);男32例,女2例;从受伤到手术平均10.7个月.所有病例均为陈旧性损伤,且均为复合韧带损伤.所有PCL损伤的病例都存在PLC损伤.合并前十字韧带损伤6例(17.6%),合并前十字韧带、内侧副韧带损伤2例(5.9%),合并内侧副韧带损伤5例(14.7%).对膝关节PLC损伤进行分型,采用不同的重建技术进行治疗.对于A型旋转不稳定,采用全关节镜下腘肌腱重建、腘肌腱联合腘腓韧带重建;对于C型后外不稳定,采用全关节镜下PLC解剖重建.结果 14例患者获得随访并进行二次关节镜检查,平均随访18.5个月(13～25个月).终末随访包括:膝关节查体、KT-1000测量、膝关节应力像和胫骨外旋稳定性.使用膝关节应力像测量胫骨后移程度,胫骨后移由术前平均15.56mm减少为术后5.16mm,手术前后差异有统计学意义.使用屈膝30°位胫骨外旋试验评估膝关节后外旋转不稳定.对比患侧与健侧胫骨外旋的差值,由术前平均14.92°减小为术后-0.22°,手术前后差异有统计学意义.术后患者平均屈曲受限4.23°,无伸膝受限.结论 对于膝关节PLC损伤导致的不稳定,采用全关节镜下PLC重建的手术技术,能够有效恢复膝关节后外旋转不稳定.这种手术技术能够与PCL重建联合应用.

Abstract：

Objectiye To introduce the surgical technique of arthroscopy assisted anatomical posterolateral corner (PLC) reconstruction,including popliteal ligament,popliteofibular ligament and lateral collateral ligament,and evaluate the results of this technique.Methods From August 2008 to April 2010,34arthroscopic posterior cruciate ligament (PCL) and PLC reconstruction surgeries were performed.The average age of the patients was 34.1 (15-52) years.There were 32 males and 2 females.The average time period from injury to surgery was 10.7 months.All patients were chronic injuries and combined ligament injuries,including PCL and PLC injuries.Some cases had other ligament injury,including 6 patients of anterior cruciate ligament (ACL) injury (17.6%),2 of ACL combined medial cruciate ligament (MCL) injuries (5.9%),and 5 of MCL injuries (14.7%).According to Fanellis classification,for type A posterolateral rotation instability,we performed arthroscopic popliteal ligament reconstruction or popliteal ligament combined popliteofibular ligament reconstruction.For type C posterolateral instability,we performed arthroscopic PLC anatomical reconstruction.Results During the follow-up period,14 patients had undergone a second look arthroscopic examination and removal of hardware.The average follow-up time was 18.5 months (13-25 months).At the final follow-up,physical examination,stability evaluation with KT-1000 and Telos stress view,and dial test were performed.The posterior displacement of the knee had decreased from 15.56 mm preoperatively to 5.16mm postoperatively.The external rotation instability had decreased from 14.92° preoperatively to -0.22°postoperatively.The average limitation of knee flexion was 4.23° and no knee extension was limited.Conclusion With the surgical technique of arthroscopy assisted anatomical PLC reconstruction,we can restore the external rotation stability of knee.This technique can be performed combine with PCL reconstruction.     

Anterolateral rotatory instability in vivo correlates tunnel position after anterior cruciate ligament reconstruction using bone-patellar tendon-bone graft

AIM To quantitatively assess rotatory and anterior-posterior instability in vivo after anterior cruciate ligament(ACL) reconstruction using bone-patellar tendon-bone(BTB) autografts, and to clarify the influence of tunnel positions on the knee stability.METHODS Single-bundle ACL reconstruction with BTB autograft was performed on 50 patients with a mean age of 28 years using the trans-tibial(TT)(n = 20) and trans-portal(TP)(n = 30) techniques. Femoral and tibial tunnel positions were identified from the high-resolution 3 D-CT bone models two weeks after surgery. Anterolateral rotatory translation was examined using a Slocum anterolateral rotatory instability test in open magnetic resonance imaging(MRI) 1.0-1.5 years after surgery, by measuring anterior tibial translation at the medial and lateral compartments on its sagittal images. Anterior-posterior stability was evaluated with a Kneelax3 arthrometer.RESULTS A total of 40 patients(80%) were finally followed up. Femoral tunnel positions were shallower(P 0.01) and higher(P 0.001), and tibial tunnel positions were more posterior(P 0.05) in the TT group compared with the TP group. Anterolateral rotatory translations in reconstructed knees were significantly correlated with the shallow femoral tunnel positions(R = 0.42, P 0.01), and the rotatory translations were greater in the TT group(3.2 ± 1.6 mm) than in the TP group(2.0 ± 1.8 mm)(P 0.05). Side-to-side differences of Kneelax3 arthrometer were 1.5 ± 1.3 mm in the TT, and 1.7 ± 1.6 mm in the TP group(N.S.). Lysholm scores, KOOS subscales and reinjury rate showed no difference between the two groups.CONCLUSION Anterolateral rotatory instability significantly correlated shallow femoral tunnel positions after ACL reconstruction using BTB autografts. Clinical outcomes, rotatory and anterior-posterior stability were overall satisfactory in both techniques, but the TT technique located femoral tunnels in shallower and higher positions, and tibial tunnels in more posterior positions than the TP technique, thus increased the anterolateral rotation. Anatomic ACL reconstruction with BTB autografts may restore knee function and stability.     

Anatomic assessment of femoral tunnel by transtibial drilling technique in double-bundle anterior cruciate liga- ment reconstruction： an in vivo study

Objective： To evaluate the anatomy of femoral tunnels created by simulated transtibial technique in double-bundle anterior cruciate ligament （ACL） reconstruction. Methods： Two tibial tunnels, anteromedial （AM） and posterolateral （PL）, were drilled 45° and 55° to tibial plateau respectively. On the femoral side, the AM and PL tunnels were drilled through anteriomedial portal. After the four tun- nels were established, the shaft of a reamer was introduced into the joint through tibial tunnel and reached against the lateral wall of intercondylar notch. The position that the reamer shaft can reach was marked and recorded. Results： Neither femoral AM nor PL tunnel opening can be fully or partially reached by the reamer shaft through the tibial AM tunnel in all cases. The evaluation through the tibial PL tunnel showed that only in 8 of 50 cases （16%） the femoral AM tunnel opening and in 4 cases （8%） the PL opening can be fully reached. On the other hand, in 12 cases （24%） the femoral AM tunnel opening and in 10 cases （20%） the PL opening can be partially reached by the shafts through the tibial PL tunnel. Conclusion： The result strongly suggests that transtibial technique is not well competent for femoral tun- nel drilling in anatomic double-bundle ACL reconstruction as we have hypothesized.     

Arthroscopic single-bundle reconstruction of posterior cruciate ligament with quadrupled hamstring tendon

Objective： To evaluate the technique and outcome of arthroscopic sipy, le-bundie reconstruction of posterior crudate ligament （PCL） with quadrupled hamstring tendon. Methods： From April 2001 to October 2004, 49 knees with PCL tears in 49 patients were verified with arthroscope in this department. Of them, 13 were combined with anterior cruciate ligament tears, 14 with disruptions of the posterolateral comer, 6 with ruptures of the posteromedial corner and medial collateral ligament, 9 with lateral meniscus tears, 5 with medial meniscus tears and 2 with popliteal vascular tears. All the damaged PCLs were reconstructed with single-bundie of autogenous quadrupled hamstring tendons under arthroscope. Biodegradable interference screws or blunt titanium interference screws were used for direct anatomic fixation of the reconstructed ligament. Results： After operation, no severe complications occurred at early stage in the 49 patients. All of them were followed up for 10-52 months with an average of 22. 0 months ＋ 10. 7 months. Lysholm score was remarkably improved from 30-60 （ mean： 47.96 ＋ 8. 16） preoperatively to 70-95 （ mean： 89. 08 ＋ 6. 10 ） at the last postoperative follow-up （ P 〈 0.01 ）. Furthermore, there was a significant improvement in International Knee Documentation Committee （IKDC） score from abnormal （ Grade C） in 10 knees and severely abnormal （Grade D ） in 39 preoperatively to normal （ Grade A ） in 20, nearly normal （ Grade B） in 24 and abnormal in 5 at the last follow-up. Of the 49 patients, 40 returned to the same activity level as before and 9 were under the level. Conclusions： Single-bundle reconstruction of PCL with quadrupled hamstring tendons has the advantage of minimal trauma in surgery and satisfactory outcome.     

Biomechanical comparison of tibial inlay and tibial tunnel techniques for reconstruction of the posterior cruciate ligament. Analysis of graft forces

BACKGROUND: The tibial inlay technique of reconstruction of the posterior cruciate ligament offers potential advantages over the conventional transtibial tunnel technique, particularly with regard to the graft force levels that develop over a functional range of knee flexion. Abnormally high graft forces generated during rehabilitation activities could lead to stretch-out of the graft during the critical early healing period. The purpose of this study was to compare graft forces between these two techniques and with forces in the native posterior cruciate ligament. METHODS: A load cell was installed at the femoral origin of the posterior cruciate ligament in twelve fresh-frozen cadaveric knees to measure resultant forces in the ligament during a series of knee loading tests. The posterior cruciate ligament was then excised, and the femoral ends of 10-mm-wide bone-patellar tendon-bone grafts were attached to the load cell to measure resultant forces in the grafts. For the tunnel reconstruction, the distal bone block of the graft was placed into a tibial tunnel and thin stainless-steel cables interwoven into the bone block were gripped in a split clamp attached to the anterior tibial cortex. With the inlay technique, the distal bone block was fixed in a tibial trough with use of a cortical bone screw with a washer and nut. The proximal ends of all grafts were pretensioned to a level of force that restored intact knee laxity at 90 degrees of flexion, and loading tests were repeated. RESULTS: There were no significant differences in mean graft forces between the two techniques under tibial loads consisting of 100 N of posterior tibial force, 5 N-m of varus and valgus moment, and 5 N-m of internal and external tibial torque. Mean graft forces with the tibial tunnel technique were approximately 10 to 20 N higher than those with the inlay technique with passive knee flexion beyond 95 degrees. Mean graft forces with both reconstruction techniques were significantly higher than forces in the native posterior cruciate ligament with the knee flexed beyond approximately 90 degrees for all but one mode of loading. CONCLUSIONS: In this cadaveric testing model, neither technique for reconstruction of the posterior cruciate ligament had a substantial advantage over the other with respect to generation of graft forces.     

Effect of the angle of the femoral and tibial tunnels in the coronal plane and incremental excision of the posterior cruciate ligament on tension of an anterior cruciate ligament graft: an in vitro study

BACKGROUND: High tension in an anterior cruciate ligament graft adversely affects both the graft and the knee; however, it is unknown why high graft tension in flexion occurs in association with a posterior femoral tunnel. The purpose of the present study was to determine the effect of the angle of the femoral and tibial tunnels in the coronal plane and incremental excision of the posterior cruciate ligament on the tension of an anterior cruciate ligament graft during passive flexion. METHODS: Eight cadaveric knees were tested. The angle of the tibial tunnel was varied to 60 degrees, 70 degrees, and 80 degrees in the coronal plane with use of three interchangeable, low-friction bushings. The femoral tunnel, with a 1-mm-thick posterior wall, was drilled through the tibial tunnel bushing with use of the transtibial technique. After the graft had been tested in all three tibial bushings with one femoral tunnel, the femoral tunnel was filled with bone cement and the tunnel combinations were tested. Lastly, the graft was replaced in the 80 degrees femoral and tibial tunnels, and the tests were repeated with excision of the lateral edge of the posterior cruciate ligament in 2-mm increments. Graft tension, the flexion angle, and anteroposterior laxity were recorded in a six-degrees-of-freedom load-application system that passively moved the knee from 0 degrees to 120 degrees of flexion. RESULTS: The graft tension at 120 degrees of flexion was affected by the angle of the femoral tunnel and by incremental excision of the posterior cruciate ligament. The highest graft tension at 120 degrees of flexion was 169 +/- 9 N, which was detected with the graft in the 80 degrees femoral and 80 degrees tibial tunnels. The lowest graft tension at 120 degrees of flexion was 76 +/- 8 N, which was detected with the graft in the 60 degrees femoral and 60 degrees tibial tunnels. The graft tension of 76 N at 120 degrees of flexion with the graft in the 60 degrees femoral and 60 degrees tibial tunnels was closer to the tension in the intact anterior cruciate ligament. Excision of the lateral edge of the posterior cruciate ligament in 2 and 4-mm increments significantly lowered the graft tension at 120 degrees of flexion without changing the anteroposterior position of the tibia. CONCLUSIONS: Placing the femoral tunnel at 60 degrees in the coronal plane lowers graft tension in flexion. Our results suggest that high graft tension in flexion is caused by impingement of the graft against the posterior cruciate ligament, which results from placing the femoral tunnel medially at the apex of the notch in the coronal plane.     

Accuracy in tunnel placement for ACL reconstruction. Comparison of traditional arthroscopic and computer-assisted navigation techniques.

The purpose of this randomized, prospective study was to compare accuracy in tunnel placement as performed with a traditional arthroscopic anterior cruciate ligament (ACL) reconstruction technique and with KneeNavTM ACL, a computer-assisted surgical navigation technique. Two surgeons experienced in ACL reconstruction, but inexperienced in computer-assisted surgical navigation technique, each randomly used traditional arthroscopic guides or KneeNavTM ACL to drill a tunnel in twenty identical foam knees. Placement of the resulting tibial and femoral tunnels was measured with a computer-assisted digitizing method and compared to traditional biplanar radiographs. Statistical analysis with Student's t-test was used to compare the distance from the ideal tunnel placement to the femoral and tibial tunnels. Accuracy of tunnel placement with KneeNavTM ACL was significantly better than that obtained with the traditional arthroscopic technique. Distances from the ideal tunnel placement to the femoral and tibial tunnels were 4.2 +/- 1.8 mm (mean +/- SD) and 4.9 +/- 2.3 mm, respectively, for the traditional arthroscopic technique, and 2.7 +/- 1.9 mm (femur) and 3.4 +/- 2.3 mm (tibia) for KneeNavTM ACL. These differences were statistically different. Tunnel placement for ACL reconstruction with KneeNavTM ACL, an image-based, computer-assisted surgical navigation device with a simple and intuitive interface, was more accurate than with the traditional arthroscopic technique.     

Arthroscopic posterior cruciate ligament reconstruction using a one-incision technique

Thirty-seven patients with a posterior cruciate ligament injury underwent arthroscopic posterior cruciate ligament reconstruction using a one-incision technique with bone-patellar tendon-bone autograft or allograft. The tibial tunnel was started at the distal end of the graft donor site on the proximal tibia and exited posteriorly at the flat spot 15 mm below the articular margin and just lateral to the midline. The femoral tunnel was made through the lateral anterolateral portal. The 25 mm long proximal bone plug was passed easily through the tibial tunnel using a specially designed suture pusher and guided into the femoral tunnel by pulling the leading suture with the knee flexed 30 degrees. Firm proximal and distal fixations were achieved with interference screws. At a minimum 2 year followup (range, 24-68 months), average knee ligament evaluation scores were 91.1 (range, 67-99) in the Lysholm knee scoring scale and 89.3 (range, 67-99) in the Hospital for Special Surgery knee ligament rating form. The average side to side difference of the posterior translation measured by the KT 2000 arthrometer was 6.08 (range, 5-7 mm) mm preoperatively and 2.2 (range, 0-6 mm) mm postoperatively. There were no significant differences between the acute and the chronic cases. The results of the isolated posterior cruciate ligament injury group were better than the combined ligamentous injury group. The one-incision technique minimizes injury to the extensor mechanism, especially the vastus medialis obliquus muscle, and medial scar. Rigid fixation of the long proximal bone plug allows early rehabilitation.     

Double-bundle PCL and Posterolateral Corner Reconstruction Components are Codominant

A more complete biomechanical understanding of a combined posterior cruciate ligament and posterolateral corner knee reconstruction may help surgeons develop uniformly accepted clinical surgical techniques that restore normal anatomy and protect the knee from premature arthritic changes. We identified the in situ force patterns of the individual components of a combined double-bundle posterior cruciate ligament and posterolateral corner knee reconstruction. We tested 10 human cadaveric knees using a robotic testing system by sequentially cutting and reconstructing the posterior cruciate ligament and posterolateral corner. The knees were subjected to a 134-N posterior tibial load and 5-Nm external tibial torque. The posterior cruciate ligament was reconstructed with a double-bundle technique. The posterolateral corner reconstruction included reattaching the popliteus tendon to its femoral origin and reconstructing the popliteofibular ligament. The in situ forces in the anterolateral bundle were greater in the posterolateral corner-deficient state than in the posterolateral corner-reconstructed state at 30° under the posterior tibial load and at 90° under the external tibial torque. We observed no differences in the in situ forces between the anterolateral and posteromedial bundles under any loading condition. The popliteus tendon and popliteofibular ligament had similar in situ forces at all flexion angles. The data suggest the two bundles protect each other by functioning in a load-sharing, codominant fashion, with no component dominating at any flexion angle. We believe the findings support reconstructing both posterior cruciate ligament bundles and both posterolateral corner components. One or more of the authors (CDH) have received funding from the Aircast Foundation, Pittsburgh, PA. Each author certifies that his or her institution either has waived or does not require approval for the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research.     

后交叉韧带胫骨止点与双束重建胫骨骨道定位的临床解剖学研究

目的 解剖研究后交叉韧带(PCL)胫骨止点情况,确定PCL前外侧束(ALB)与后内侧束(PMB)胫骨止点的位置、形状与面积,探讨PCL双束四骨道重建中胫骨骨道定位标志与定位方法.方法 30例成人膝关节标本,根据屈伸膝关节过程中纤维束紧张与松弛情况,将PCL分为ALB与PMB,并确定各束中的功能束,用多种指标测量ALB、PMB与功能束的胫骨止点,解剖寻找双束四骨道重建PCL中胫骨骨道定位标志与定位方法.结果 PCL胫骨止点位于后髁间窝内,其纵轴由近内斜向远外,与胫骨干夹角平均为(16.5±1.4)°.ALB与PMB胫骨止点基本呈远近排列,ALB胫骨止点接近于菱形,平均面积为(90±20)mm2,PMB胫骨止点近似长方形,平均面积(96±32)mm2,二者无显著差异(P>0.05).ALB与PMB中均存在功能束,分别止于ALB胫骨止点的远外侧部及PMB胫骨止点的远内侧部,均接近椭圆形,面积分别为(35±12)mm2与(36±6)mm2,二者无显著差异(P>0.05).ALB功能束胫骨止点中心与PMB功能束胫骨止点中心距离为(12.7 ±1.9)mm.胫骨内、外侧髁间棘及胫骨上端后方骨嵴为重要的解剖标志.结论 PCL胫骨止点可以容纳两个胫骨骨道,PCL的ALB与PMB中均存在功能束,提示临床双束四骨道重建PCL时,胫骨骨道应分别定位于ALB与PMB功能束胫骨止点处.     

胫骨骨道定位对前交叉韧带单束重建的影响

[目的]探讨胫骨骨隧道定位对前交叉韧带单束重建术后临床疗效的影响.[方法]将60例前交叉韧带断裂患者随机分为对照组和观察组.对照组胫骨骨隧道内口采用外侧半月板游离缘的切线与前后髁间突连线的交点定位;观察组选择原前内侧束和后外侧束中间位置定位.术后矢状位MRI测量胫骨骨道位置、胫骨纵向位移、后交叉韧带指数、膝关节功能评分进行分析评价.[结果]对照组和观察组胫骨骨道分别位于胫骨平台全长的前(38.67±4.23)％和(34.21±2.46)％.胫骨纵向位移为(11.14±2.64)mm和(14.34±2.23)mm,上倾角为(56.2±4.3)°和(44.6±5.2)°,后交叉韧带指数为(3.97±0.45)和(4.78±0.78);两组比较差异均有统计学意义(t检验,P＜0.05).术后1年,对照组与观察组IKDC膝关节主观评分分别为(79.63±4.67)分和(89.76±5.21)分;Lysholm评分分别为(85.61±4.92)分和(92.54±3.22)分,两组比较差异有统计学意义(t检验,P＜0.05).[结论]前交叉韧带单束重建能使患者的关节稳定性与功能均得到显著改善.膝关节MRI测量可较客观、准确地反映胫骨的骨道定位情况.理想的胫骨骨道在矢状位MRI上位于胫骨平台的前(34.21±2.46)％.     

Reconstructive interventions of the posterior cruciate ligament--experimental studies of isometric aspects. Part II: Studies of the posterior cruciate ligament replacement model]

Isometric positioning of the posterior cruciate ligament (PCL) graft is important for successful reconstruction of the PCL-deficient knee. This study documents the relationship between graft placement and changes in intra-articular graft length during passive range of motion of the knee. In eight cadaveric knees the PCL was identified and cut. The specimens were mounted in a stabilizing rig. PCL reconstruction was performed using a 9-mm-thick synthetic cord that was passed through tunnels 10 mm in diameter. Three different femoral graft placement sites were evaluated: (1) in four specimens the tunnel was located around the femoral isometric point, (2) in two specimens the tunnel was positioned over the guide wire 5 mm anterior to the femoral isometric point, (3) in two specimens the tunnel was positioned over the guide wire 5 mm posterior to the isometric femoral point. In all knees only one tibial tunnel was created around the isometric tibial point. The location of the isometric points was described in part I of the study. The proximal end of the cord was fixed to the lateral aspect of the femur. Distally the cord was attached to a measuring unit. The knees were flexed from 0 degree to 110 degrees, and the changes in the graft distance between the femoral attachment sites were measured in 10 degrees steps. Over the entire range of motion measured the femoral tunnels positioned around the isometric point produced femorotibial distance changes of within 2 mm. The anteriorly placed tunnels produced considerable increases in femorotibial distance with knee flexion, e.g. about 8 mm at 110 degrees of flexion.(ABSTRACT TRUNCATED AT 250 WORDS)