Effect of ACL graft material on anterior knee force during simulated in vivo ovine motion applied to the porcine knee: An in vitro examination of force during 2000 cycles

This study determined how anterior cruciate ligament (ACL) reconstruction affected the magnitude and temporal patterns of anterior knee force and internal knee moment during 2000 cycles of simulated gait. Porcine knees were tested using a six degree‐of‐freedom robot, examining three porcine allograft materials compared with the native ACL. Reconstructions were performed using: (1) bone‐patellar tendon‐bone allograft (BPTB), (2) reconstructive porcine tissue matrix (RTM), or (3) an RTM‐polymer hybrid construct (Hybrid). Forces and moments were measured over the entire gait cycle and contrasted at heel strike, mid stance, toe off, and peak flexion. The Hybrid construct performed the best, as magnitude and temporal changes in both anterior knee force and internal knee moment were not different from the native ACL knee. Conversely, the RTM knees showed greater loss in anterior knee force during 2000 cycles than the native ACL knee at heel strike and toe off, with an average force loss of 46%. BPTB knees performed the least favorably, with significant loss in anterior knee force at all key points and an average force loss of 61%. This is clinically relevant, as increases in post‐operative knee laxity are believed to play a role in graft failure and early onset osteoarthritis. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1789–1795, 2015.     

Operative and nonoperative management of anterior cruciate ligament injury: Differences in gait biomechanics at 5 years

Gait biomechanics after anterior cruciate ligament (ACL) injury are associated with functional outcomes and the development of posttraumatic knee osteoarthritis. However, biomechanical outcomes between patients treated nonoperatively compared with operatively are not well understood. The primary purpose of this study was to compare knee joint contact forces, angles, and moments during loading response of gait between individuals treated with operative compared with nonoperative management at 5 years after ACL injury. Forty athletes treated operatively and 17 athletes treated nonoperatively completed gait analysis at 5 years after ACL reconstruction or completion of nonoperative rehabilitation. Medial compartment joint contact forces were estimated using a previously validated, patient-specific electromyography-driven musculoskeletal model. Knee joint contact forces, angles, and moments were compared between the operative and nonoperative group using mixed model 2 × 2 analyses of variance. Peak medial compartment contact forces were larger in the involved limb of the nonoperative group (Op: 2.37 ± 0.47 BW, Non-Op: 3.03 ± 0.53 BW; effect size: 1.36). Peak external knee adduction moment was also larger in the involved limb of the nonoperative group (Op: 0.25 ± 0.08 Nm/kg·m, Non-Op: 0.32 ± 0.09 Nm/kg·m; effect size: 0.89). No differences in radiographic tibiofemoral osteoarthritis were present between the operative and nonoperative groups. Overall, participants treated nonoperatively walked with greater measures of medial compartment joint loading than those treated operatively, while sagittal plane group differences were not present. Statement of clinical relevance: The differences in medial knee joint loading at 5 years after operative and nonoperative management of ACL injury may have implications on the development of posttraumatic knee osteoarthritis.     

A systematic review of randomized controlled clinical trials comparing hamstring autografts versus bone-patellar tendon-bone autografts for the reconstruction of the anterior cruciate ligament

Objectives

Controversies exist over which type of graft is best for the reconstruction of the anterior cruciate ligament (ACL). The purpose of this systematic review was to evaluate the effectiveness of ACL reconstruction using either hamstring (HT) autografts or bone-patellar tendon-bone (BPTB) autografts.

Methods

We searched the Cochrane Library, MEDLINE and EMBASE for published randomized controlled trials (RCT) comparing HT autografts with BPTB autografts for ACL reconstruction. Data analyses were performed using Cochrane Collaboration RevMan 5.0.

Results

Nine RCTs (738 patients) met the inclusion criteria. The combined results of the meta-analysis indicated there was a significantly lower rate of negative Pivot test [relative risk (RR) 0.87, 95?% confidence intervals (CI) 0.79–0.96, P?=?0.004], anterior knee pain (RR 0.66, 95?% CI 0.45–0.96, P?=?0.03) and of kneeling pain (RR 0.49, 95?% CI 0.27–0.91, P?=?0.02) in the HT group than in the BPTB group.

Conclusions

ACL reconstruction with HT autografts or BPTB autografts achieved similar postoperative effects in terms of restoring knee joint function. HT autografts were inferior to BPTB autografts for restoring knee joint stability, but were associated with fewer postoperative complications.     

Comparison of the ACL and ACL graft forces before and after ACL reconstruction: an in-vitro robotic investigation

Background Long-term follow-up studies have indi-cated that there is an increased incidence of arthrosis following anterior cruciate ligament (ACL) reconstruc-tion, suggesting that the reconstruction may not repro-duce intact ACL biomechanics. We studied not only the magnitude but also the orientation of the ACL and ACL graft forces

Methods 10 knee specimens were tested on a robotic testing system with the ACL intact, deficient, and recon-structed (using a bone-patella tendon-bone graft). The magnitude and orientation of the ACL and ACL graft forces were determined under an anterior tibial load of 130 N at full extension, and 15, 30, 60, and 90° of flexion. Orientation was described using elevation angle (the angle formed with the tibial plateau in the sagit-tal plane) and deviation angle (the angle formed with respect to the anteroposterior direction in the transverse plane)

Results ACL reconstruction restored anterior tibial translation to within 2.6 mm of that of the intact knee under the 130-N anterior load. Average internal tibial rotation was reduced after ACL reconstruction at all flexion angles. The force vector of the ACL graft was significantly different from the ACL force vector. The average values of the elevation and deviation angles of the ACL graft forces were higher than that of the intact ACL at all flexion angles

Interpretation Contemporary single bundle ACL reconstruction restores anterior tibial translation under anterior tibial load with different forces (both magni-tude and orientation) in the graft compared to the intact ACL. Such graft function might alter knee kinematics in other degrees of freedom and could overly constrain the tibial rotation. An anatomic ACL reconstruction should reproduce the magnitude and orientation of the intact ACL force vector, so that the 6-degrees-of-freedom knee kinematics and joint reaction forces can be restored.     

Effects of ACL graft placement on in vivo knee function and cartilage thickness distributions

Injuries to the anterior cruciate ligament (ACL) frequently lead to early‐onset osteoarthritis. Despite advancement in surgical techniques, ACL reconstruction has a limited ability to prevent these degenerative changes. While previous studies have investigated knee function after ACL reconstruction, in vivo investigations of the effects of graft placement on in vivo joint function and cartilage health are limited. This review presents a series of studies that used novel imaging and 3D modeling techniques to determine the in vivo placement of the ACL graft on the femur using two different ACL reconstruction techniques. These techniques resulted in two distinct graft placement groups: one where the ACL was placed anatomically near the center of the native ACL footprint and another where the graft was placed anteroproximally on the femur, centered outside the ACL footprint. We quantified the effects of graft placement on graft deformation during in vivo loading and how these variables affected knee motion. Finally, we quantified whether femoral placement of the graft affected cartilage thickness. Our results demonstrate that achieving anatomic graft placement on the femur is critical to restoring native ACL function and normal knee kinematics. Knees with grafts that more closely restored normal ACL function, and thus knee motion, experienced less focal cartilage thinning than did those that experienced abnormal knee motion. These results suggest that achieving anatomic graft placement is a critical factor in restoring normal knee motion and potentially slowing the development of degenerative changes after ACL reconstruction. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1160–1170, 2017.

     

Lower limb kinematic alterations during drop vertical jumps in female athletes who have undergone anterior cruciate ligament reconstruction

The aim of this study was to determine if anterior cruciate ligament reconstructed (ACL‐R) female athletes exhibit altered lower limb kinematic profiles during jump landing when compared to a non‐injured age, sex, and activity matched control group. Fourteen ACL‐R and 14 non‐injured control subjects performed 3 vertical drop jump (DVJ) trials. Lower limb kinematics were recorded at 200 Hz. Peak and time‐averaged angular displacements were quantified and utilized for between‐group analysis. The ACL‐R group displayed altered hip joint frontal and transverse plane kinematic alterations, and knee joint frontal and sagittal plane kinematic alterations. Specifically the ACL‐R group displayed an increased adducted (p < 0.05) and internally rotated (p < 0.05) hip joint position, both peak and time‐averaged, following landing. The ACL‐R group also displayed a decreased adducted (p < 0.05) and flexed (p < 0.05) position of the knee joint following landing. The observed aberrant lower limb kinematics could pre‐dispose ACL‐R athletes to potential future knee joint injuries. Further studies are required to determine in a prospective manner whether such deficits increase the incidence of recurrent ACL injury, and whether specific sensorimotor protocols following ACL reconstruction can minimize these kinematic deficits. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:72–78, 2012     

Contribution of tibiofemoral joint contact to net loads at the knee in gait

Inverse dynamics analysis is commonly used to estimate the net loads at a joint during human motion. Most lower‐limb models of movement represent the knee as a simple hinge joint when calculating muscle forces. This approach is limited because it neglects the contributions from tibiofemoral joint contact forces and may therefore lead to errors in estimated muscle forces. The aim of this study was to quantify the contributions of tibiofemoral joint contact loads to the net knee loads calculated from inverse dynamics for multiple subjects and multiple gait patterns. Tibiofemoral joint contact loads were measured in four subjects with instrumented implants as each subject walked at their preferred speed (normal gait) and performed prescribed gait modifications designed to treat medial knee osteoarthritis. Tibiofemoral contact loads contributed substantially to the net knee extension and knee adduction moments in normal gait with mean values of 16% and 54%, respectively. These findings suggest that knee‐contact kinematics and loads should be included in lower‐limb models of movement for more accurate determination of muscle forces. The results of this study may be used to guide the development of more realistic lower‐limb models that account for the effects of tibiofemoral joint contact at the knee. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1054–1060, 2015.     

Comparison of the ACL and ACL graft forces before and after ACL reconstruction an in-vitro robotic investigation

Background?Long-term follow-up studies have indi-cated that there is an increased incidence of arthrosis following anterior cruciate ligament (ACL) reconstruc-tion, suggesting that the reconstruction may not repro-duce intact ACL biomechanics. We studied not only the magnitude but also the orientation of the ACL and ACL graft forces

Methods?10 knee specimens were tested on a robotic testing system with the ACL intact, deficient, and recon-structed (using a bone-patella tendon-bone graft). The magnitude and orientation of the ACL and ACL graft forces were determined under an anterior tibial load of 130?N at full extension, and 15, 30, 60, and 90° of flexion. Orientation was described using elevation angle (the angle formed with the tibial plateau in the sagit-tal plane) and deviation angle (the angle formed with respect to the anteroposterior direction in the transverse plane)

Results?ACL reconstruction restored anterior tibial translation to within 2.6?mm of that of the intact knee under the 130-N anterior load. Average internal tibial rotation was reduced after ACL reconstruction at all flexion angles. The force vector of the ACL graft was significantly different from the ACL force vector. The average values of the elevation and deviation angles of the ACL graft forces were higher than that of the intact ACL at all flexion angles

Interpretation?Contemporary single bundle ACL reconstruction restores anterior tibial translation under anterior tibial load with different forces (both magni-tude and orientation) in the graft compared to the intact ACL. Such graft function might alter knee kinematics in other degrees of freedom and could overly constrain the tibial rotation. An anatomic ACL reconstruction should reproduce the magnitude and orientation of the intact ACL force vector, so that the 6-degrees-of-freedom knee kinematics and joint reaction forces can be restored.     

Rectangular Tunnel Double-Bundle Anterior Cruciate Ligament Reconstruction with Bone–Patellar Tendon–Bone Graft to Mimic Natural Fiber Arrangement

We describe our current technique of anatomic, double-bundle (DB), rectangular tunnel anterior cruciate ligament (ACL) reconstruction with bone–patellar tendon–bone (BPTB) graft. This technique mimics the natural, or anatomic, arrangement of the native ACL fibers. This technique has the following advantages: (1) creation of a DB ACL reconstruction with a single BPTB graft; (2) maximization of graft–tunnel contact area; (3) containment of the tunnel apertures within the anatomic ACL attachment footprint; (4) rotational control of the graft within the tunnels during and after fixation; and (5) preservation of notch anatomy.     

Evaluation of knee joint muscle forces and tissue stresses‐strains during gait in severe OA versus normal subjects

Osteoarthritis (OA) is the leading cause of pain and disability in the elderly with the knee being the most affected weight bearing joint. We used a musculoskeletal biomechanical model of the lower extremity including a detailed validated knee joint finite element model to compute lower extremity muscle forces and knee joint stresses‐strains during the stance phase of gait. The model was driven by gait data on OA patients, and results were compared with those of the same model driven by data on normal controls. Additional analyses were performed with altered cartilage‐menisci properties to evaluate the effects of deterioration during OA. In OA patients compared to normal subjects, muscle forces dropped at nearly all stance periods except mid‐stance. Force in the anterior cruciate ligament remained overall the same. Total contact forces‐stresses deceased by about 25%. Alterations in properties due to OA had negligible effects on muscle forces, but increased contact areas and cartilage strains and reduced contact pressures. Reductions in contact stresses and increases in tissue strains and transfer of load via menisci are partly due to the altered kinetics‐kinematics of gait and partly due to deterioration in cartilage‐menisci properties in OA patients. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:69–78, 2014.     

Vordere Kreuzbandplastik mit proximaler Endobutton-Fixation eines Lig.-patellae-Transplantats

BACKGROUND: Interference screw fixation in ACL reconstruction with bone-patellar tendon-bone graft (BPTB) is a potential source of intraoperative complications such as graft laceration. Further problems are artifacts on MRI and screw removal in revision surgery. These problems can be avoided by using distant fixation with the EndoButton. We designed this study to evaluate the clinical as well as the subjective outcome of ACL reconstruction with BPTB graft and femoral fixation with the EndoButton. METHODS: A total of 51 patients (7 female, 44 male) were examined 2-5 years after ACL reconstruction with BPTB graft and femoral fixation with the EndoButton. We used the IKDC form, Lysholm score, Tegner activity score, and digital radiographs (AP, lateral, axial) for the evaluation. RESULTS: Of all the patients included in the study, 87% showed a "normal" or "nearly normal" knee function according to the IKDC score, Lysholm score 94.2+/-7.9, Tegner score 6.4+/-1.2, and subjective IKDC 89.9+/-11.9. Radiological signs of arthritic changes could be seen in ten cases. CONCLUSION: The clinical outcome of ACL reconstruction with EndoButton fixation is comparable to other studies on ACL reconstruction with interference screw fixation. However, since the EndoButton avoids potential problems of the interference screw fixation, we recommend this fixation technique for ACL reconstruction with BPTB graft.     

Biomechanics of the anterior cruciate ligament and implications for surgical reconstruction

Abstract Injury to the anterior cruciate ligament (ACL) is regarded as critical to the physiological kinematics of the femoral-tibial joint, its disruption eventually causing long-term functional impairment. Both the initial trauma and the pathologic motion pattern of the injured knee may result in primary degenerative lesions of the secondary stabilisers of the knee, each of which are associated with the early onset of osteoarthritis. Consequently, there is a wide consensus that young and active patients may profit from reconstructing the ACL. Several factors have been identified as significantly influencing the biomechanical characteristics and the functional outcome of an ACL reconstructed knee joint. These factors are: (1) individual choice of autologous graft material using either patellar tendon-bone grafts or quadrupled hamstring tendon grafts, (2) anatomical bone tunnel placement within the footprints of the native ACL, (3) adequate substitute tension after cyclic graft preconditioning, and (4) graft fixation close to the joint line using biodegradable graft fixation materials that provide an initial fixation strength exceeding those loads commonly expected during rehabilitation. Under observance of these factors, the literature encourages mid-to long-term clinical and functional outcomes after ACL reconstruction.     

Functional and radiographic consideration of lower limb malalignment in children and adolescents with idiopathic genu valgum

Three‐dimensional gait analysis is capable of assessing dynamic load characteristics and the resulting compensatory effects of lower limb malalignment, which are generally not reflected in static imaging. This study determined differences in gait parameters in the frontal and transverse plane between patients and controls in order to identify compensatory mechanisms, and to correlate radiographic measurements and gait parameters in a consecutive series of children with idiopathic genu valgum. Thirty‐three patients (mean age 12.3 years) were retrospectively reviewed and compared to a healthy control group. Children with genu valgum demonstrated significantly decreased internal knee valgus moments, shifting into varus moments. Furthermore, significantly different transverse plane gait patterns (decreased external knee rotation, increased external hip rotation) were observed. These patterns showed a relevant influence on the frontal knee moments, with knee rotation and foot progression angle showing the highest predictive value for changes and possible compensation of frontal knee moments. The correlation between commonly used radiographic measurements (i.e., mechanical axis deviation) and findings of the gait analysis was only low. Besides showing decreased internal knee valgus moments, our results suggest that considerable compensatory gait mechanisms may be present in children with idiopathic genu valgum to reduce joint loading. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1362–1370, 2014.     

Effect of reconstruction of the anterior cruciate ligament on proprioception of the knee and the heel strike transient

Abnormal proprioception of the knee joint has been documented after rupture of the anterior cruciate ligament (ACL) and may result in the loss of muscular reflexes. Excessive loading from the lack of muscular control may predispose the joint to osteoarthrosis. To investigate this problem, 10 patients were studied at an average of 31.6 months after ACL reconstruction. Three tests of joint proprioception and measurements of the vertical component of heel strike force during normal gait were used. A normal control group also was studied. For two of the proprioception tests (reproduction of passive motion and relative reproduction), there were no statistical differences among the uninjured (control) limbs, the normal contralateral limb of patients with a reconstructed ACL, and the extremity with a reconstructed ACL. In the third test (threshold of detection of motion), which previously has been shown to be adversely affected by ACL injury, the measurements for both extremities of patients with a reconstructed ACL were more accurate than those for the control group. The reconstructed extremity performed less accurately than the contralateral extremity (p < 0.05). The heel strike transient (vertical component of ground reaction force at heel strike) for uninjured and ACL-reconstructed limbs was not significantly different. In fact, the extremity with the reconstructed ACL had a lower transient than the uninjured extremity. Heel strike transients in patients with a reconstructed ACL were higher than those in the controls, but the differences were significant only when corrected for velocity of gait. These results indicate that a well done ACL reconstruction with appropriate rehabilitation can result in proprioception that is essentially equal to that of the contralateral limb.     

Interaction between the ACL graft and MCL in a combined ACL+MCL knee injury using a goat model

The optimal treatment for the MCL in the combined ACL and MCL-injured knee is still controversial. Therefore, we designed this study to examine the mechanical interaction between the ACL graft and the MCL in a goat model using a robotic/universal force-moment sensor testing system. The kinematics of intact, ACL-deficient, ACL-reconstructed, and ACL-reconstructed/ MCL-deficient knees, as well as the in situ forces in the ACL, ACL graft, and MCL were determined in response to two external loading conditions: 1) anterior tibial load of 67 N and 2) valgus moment of 5 N-m. With an anterior tibial load, anterior tibial translation in the ACL-deficient knee significantly increased from 2.0 and 2.2 mm to 15.7 and 18.1 mm at 30 degrees and 60 degrees of knee flexion, respectively. The in situ forces in the MCL also increased from 8 to 27 N at 60 degrees of knee flexion. ACL reconstruction reduced the anterior tibial translation to within 2 mm of the intact knee and significantly reduced the in situ force in the MCL to 17 N. However, in response to a valgus moment, the in situ forces in the ACL graft increased significantly by 34 N after transecting the MCL. These findings show that ACL deficiency can increase the in situ forces in the MCL while ACL reconstruction can reduce the in situ forces in the MCL in response to an anterior tibial load. On the other hand, the ACL graft is subjected to significantly higher in situ forces with MCL deficiency during an applied valgus moment. Therefore, the ACL-reconstructed knee with a combined ACL and MCL injury should be protected from high valgus moments during early healing to avoid excessive loading on the graft.     

Tibiofemoral cartilage contact biomechanics in patients after reconstruction of a ruptured anterior cruciate ligament

We investigated the in vivo cartilage contact biomechanics of the tibiofemoral joint in patients after reconstruction of a ruptured anterior cruciate ligament (ACL). A dual fluoroscopic and MR imaging technique was used to investigate the cartilage contact biomechanics of the tibiofemoral joint during in vivo weight‐bearing flexion of the knee in eight patients 6 months following clinically successful reconstruction of an acute isolated ACL rupture. The location of tibiofemoral cartilage contact, size of the contact area, cartilage thickness at the contact area, and magnitude of the cartilage contact deformation of the ACL‐reconstructed knees were compared with those previously measured in intact (contralateral) knees and ACL‐deficient knees of the same subjects. Contact biomechanics of the tibiofemoral cartilage after ACL reconstruction were similar to those measured in intact knees. However, at lower flexion, the abnormal posterior and lateral shift of cartilage contact location to smaller regions of thinner tibial cartilage that has been described in ACL‐deficient knees persisted in ACL‐reconstructed knees, resulting in an increase of the magnitude of cartilage contact deformation at those flexion angles. Reconstruction of the ACL restored some of the in vivo cartilage contact biomechanics of the tibiofemoral joint to normal. Clinically, recovering anterior knee stability might be insufficient to prevent post‐operative cartilage degeneration due to lack of restoration of in vivo cartilage contact biomechanics. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1781–1788, 2012     

Influence of Hamstrings on Knee Moments During Loading Response of Gait in Individuals Following ACL Reconstruction

Biomechanical studies consistently report smaller knee extensor moments in the surgical limb during loading response (LR) of gait following ACL reconstruction (ACLr). However, this reduction in knee loading is quantified by net joint moments (NJM). As a result, in the presence of greater hamstring activity, the true contribution from the knee extensors may not be reduced. The purpose of this study is to compare hamstring activity and strength and knee joint moments between individuals post-ACLr and controls. Eighteen individuals 3 months post-ACLr and matched controls walked and net knee extensor moment peak and impulse and hamstring activity were identified during LR, as well as maximal hamstring strength. A hybrid musculoskeletal model estimated knee flexor moments from joint kinematics and hamstring electromyography. Flexor moments (SIMM) were scaled based on strength. Knee extensor moments were estimated from the sum of the net knee moment and estimated knee flexor moment; estimated extensor moment peaks and impulse were calculated during LR. Repeated measures analysis of variance compared groups and limbs. Smaller net knee extensor moment and greater hamstring activity, as well as deficits in maximal hamstring strength, were observed in the surgical limb (all p < 0.05). When accounting for the torque-producing capabilities of the knee flexors, estimated knee extensor moment peak and impulse were smaller in the surgical limb. These findings suggest that net knee moments accurately reflect smaller knee extensor loading post-ACLr. Statement of Clinical Significance: Rehabilitation programs should target increasing knee extensor loading to restore gait mechanics during early rehabilitation. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:378-386, 2020     

Investigating the effects of anterior tibial translation on anterior knee force in the porcine model: Is the porcine knee ACL dependent?

This study sought to determine anterior force in the porcine knee during simulated 6‐degree‐of‐freedom (DOF) motion to establish the role of the anterior cruciate ligament (ACL). Using a 6‐DOF robot, a simulated ovine motion was applied to porcine hind limbs while recording the corresponding forces. Since the porcine knee is more lax than the ovine knee, anterior tibial translations were superimposed on the simulated motion in 2 mm increments from 0 mm to 10 mm to find a condition that would load the ACL. Increments through 8 mm increased anterior knee force, while the 10 mm increment decreased the force. Beyond 4 mm, anterior force increases were non‐linear and less than the increases at 2 and 4 mm, which may indicate early structural damage. At 4 mm, the average anterior force was 76.9 ± 10.6 N (mean ± SEM; p < 0.025). The ACL was the primary restraint, accounting for 80–125% of anterior force throughout the range of motion. These results demonstrate the ACL dependence of the porcine knee for the simulated motion, suggesting this model as a candidate for studying ACL function. With reproducible testing conditions that challenge the ACL, this model could be used in developing and screening possible reconstruction strategies. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:641–646, 2011     

关节镜下同种异体骨-髌腱-骨双束重建膝关节前交叉韧带的临床比较研究

目的探讨关节镜下同种异体骨-髌腱-骨（bone-patellar tendon-bone,BPTB）移植物双束重建膝关节前交叉韧带（anterior cruciate ligament,ACL）的中期临床效果。方法 2003年7月～2007年7月,61例ACL断裂患者接受关节镜下BPTB重建ACL手术,按术式和移植物分为3组：异体BPTB双束组（20例）,异体BPTB单束组（21例）,自体BPTB单束组（20例）。3组平均随访时间分别为（41.6±3.0）、（42.3±3.9）、（42.5±2.7）月。通过膝关节查体、IKDC2000主观评分、Lysholm评分、Tegner评分、膝前痛、常规KT-2000、后推KT-2000及Biodex等速肌力测试系统评估手术效果。结果 3组间的IKDC2000、Lysholm、Tegner评分、大腿围度差值、肌力和常规KT-2000等指标差异无显著性（P〉0.05）。异体双束组的Pivotshift阳性发生率（5%,1/20）是异体单束组的1/6（29%,6/21）,自体单束组的1/4（20%,4/20）。异体双束组的后推KT-200030°位前移度（中位数15磅0.5 mm,20磅0.5 mm,30磅0.9 mm）明显低于其他两组（P〈0.05）。异体双束组（15%,3/20）和异体单束组（10%,2/21）的膝前痛发生率明显低于自体单束组（75%,15/20）（χ2=24.201,P=0.000）。结论同种异体BPTB双束重建ACL能够更好地恢复膝关节整体前向及旋转稳定性,减少并发症,可以作为髁间窝较宽的患者ACL初次解剖重建的理想手术方法。