The effect of anterior cruciate ligament resection on knee biomechanics.
- 作者列表："Kayani B","Konan S","Ahmed SS","Chang JS","Ayuob A","Haddad FS
AIMS:The objectives of this study were to assess the effect of anterior cruciate ligament (ACL) resection on flexion-extension gaps, mediolateral soft tissue laxity, maximum knee extension, and limb alignment during primary total knee arthroplasty (TKA). METHODS:This prospective study included 140 patients with symptomatic knee osteoarthritis undergoing primary robotic-arm assisted TKA. All operative procedures were performed by a single surgeon using a standard medial parapatellar approach. Optical motion capture technology with fixed femoral and tibial registration pins was used to assess study outcomes pre- and post-ACL resection with knee extension and 90° knee flexion. This study included 76 males (54.3%) and 64 females (45.7%) with a mean age of 64.1 years (SD 6.8) at time of surgery. Mean preoperative hip-knee-ankle deformity was 6.1° varus (SD 4.6° varus). RESULTS:ACL resection increased the mean extension gap significantly more than the flexion gap in the medial (mean 1.2 mm (SD 1.0) versus mean 0.2 mm (SD 0.7) respectively; p < 0.001) and lateral (mean 1.1 mm (SD 0.9) versus mean 0.2 mm (SD 0.6) respectively; p < 0.001) compartments. The mean gap differences following ACL resection did not create any significant mediolateral soft tissue laxity in extension (gap difference: mean 0.1 mm (SD 2.4); p = 0.89) or flexion (gap difference: mean 0.2 mm (SD 3.1); p = 0.40). ACL resection did not significantly affect maximum knee extension (change in maximum knee extension = mean 0.2° (SD 0.7°); p = 0.23) or fixed flexion deformity (mean 4.2° (SD 3.2°) pre-ACL release versus mean 3.9° (SD 3.7°) post-ACL release; p = 0.61). ACL resection did not significantly affect overall limb alignment (change in alignment = mean 0.2° valgus (SD 1.0° valgus; p = 0.11). CONCLUSION:ACL resection creates flexion-extension mismatch by increasing the extension gap more than the flexion gap. However, gap differences following ACL resection do not create any mediolateral soft tissue laxity in extension or flexion. ACL resection does not affect maximum knee extension or overall limb alignment. Cite this article: Bone Joint J 2020;102-B(4):442-448.
目标：目标本研究旨在评估前交叉韧带（ACL）切除术对全膝关节置换术（TKA）患者屈伸间隙、中外侧软组织松弛、最大伸膝和肢体对中的影响。 方法：本前瞻性研究这项研究包括140名有症状的膝关节骨性关节炎患者接受一级机械臂辅助TKA治疗。所有手术均由一名外科医生采用标准的内侧髌旁入路完成。采用带固定股骨和胫骨定位销的光学运动捕捉技术，评估膝关节伸展和90°膝关节屈曲的前交叉韧带切除术前后的疗效。这项研究包括76名男性（54.3%）和64名女性（45.7%），平均年龄64.1岁（标准偏差6.8）。术前髋膝踝畸形平均6.1°内翻（SD 4.6°内翻）。 结果：前交叉韧带切除术内侧（平均1.2 mm（标准差1.0））和外侧（平均1.1 mm（标准差0.9））和平均0.2 mm（标准差0.6）；内侧（平均1.2 mm（标准差1.0））和外侧（平均1.1 mm（标准差0.9））的平均伸展间隙明显大于屈曲间隙。前交叉韧带切除后的平均间隙差异在伸展（间隙差异：平均0.1毫米（标准差2.4）；p=0.89）或屈曲（间隙差异：平均0.2毫米（标准差3.1）；p=0.40）方面没有造成任何显著的中外侧软组织松弛。前交叉韧带切除对最大膝关节伸展（最大膝关节伸展的变化=平均0.2°（标准差0.7°）；p=0.23）或固定屈曲畸形（平均4.2°（标准差3.2°）前交叉韧带释放与平均3.9°（标准差3.7°）后交叉韧带释放没有显著影响；p=0.61）。前交叉韧带切除术对肢体整体排列无显著影响（排列变化=平均0.2°外翻（SD 1.0°外翻；p=0.11）。 C类结论：前交叉韧带切除术通过增大拉伸间隙而不是弯曲间隙来创建弯曲-拉伸不匹配。然而，前交叉韧带切除后的间隙差异在伸展或屈曲时不会造成任何中外侧软组织松弛。前交叉韧带切除不影响膝关节最大伸展或肢体整体对中。引用本文：骨关节J 2020；102-B（4）：442-448。
METHODS:Purpose To determine outcomes of transphyseal ACL reconstruction using a living parental hamstring tendon allograft in a consecutive series of 100 children. Methods One hundred consecutive juveniles undergoing ACL reconstruction with a living parental hamstring allograft were recruited prospectively and reviewed 2 years after ACL reconstruction with IKDC Knee Ligament Evaluation, and KT1000 instrumented laxity testing. Skeletally immature participants obtained annual radiographs until skeletal maturity, and long leg alignment radiographs at 2 years. Radiographic Posterior tibial slope was recorded. Results Of 100 juveniles, the median age was 14 years (range 8–16) and 68% male. At surgery, 30 juveniles were graded Tanner 1 or 2, 21 were Tanner 3 and 49 were Tanner 4 or 5. There were no cases of iatrogenic physeal injury or leg length discrepancy on long leg radiographs at 2 years, despite a median increase in height of 8 cm. Twelve patients had an ACL graft rupture and 9 had a contralateral ACL injury. Of those without further ACL injury, 82% returned to competitive sports, IKDC ligament evaluation was normal in 52% and nearly normal in 48%. The median side to side difference on manual maximum testing with the KT1000 was 2 mm (range − 1 to 5). A radiographic PTS of 12° or more was observed in 49%. Conclusions ACL reconstruction in the juvenile with living parental hamstring tendon allograft is a viable procedure associated with excellent clinical stability, patient-reported outcomes and return to sport over 2 years. Further ACL injury to the reconstructed and the contralateral knee remains a significant risk, with identical prevalence observed between the reconstructed and contralateral ACL between 12 and 24 months after surgery. Level of evidence III (Cohort Study).
METHODS:Purpose The purpose of the study was to investigate the biomechanics of walking and of the knee joint in the acute phase of ACL injury. Methods We examined 18 patients with acute ACL injuries and 20 healthy adults as controls. The biomechanics of the knee joint and of walking was assessed by 5 inertial sensors fixed with special cuffs to the lower back, the lower third of the thigh, and the lower third of the shank of the right and left legs. The movements and temporal characteristics were recorded while the subject was walking 10 m at a comfortable pace. Based on the results of examination, the patients were divided into two groups: with severe function impairment (6 patients) and with moderate function impairment (12 patients). Results It was found that in the first days post-trauma, not only the knee function was reduced, but the function of the entire lower limb as well. This led to a functional asymmetry. The kinematics of movements in the joints changed in accordance with slower walking. The walking became not only slower, but it was also associated with a decreased impact load in the weight acceptance phase. At later dates, the functional impairments were less pronounced. The total range of flexion motion did not exceed 20 degrees in the first group and 55 degrees in the second one. The injured joint developed functional immobilization within the first days post-injury. This was a guarding response by additional muscle strain to prevent unusual and limit physiological movements in the knee joint. The movements in the knee joint while walking were of small amplitude, rocking, and occurred only under load. The amplitude of the main flexion in the swing phase was reduced. Conclusion The stage of an ACL injury should be assessed not only based on the time post-trauma, but also taking account of the functional parameter—the knee range of flexion while walking. According to our findings, the only factor that had influenced the functional condition of the KJ was the duration of joint immobilization after trauma.
METHODS:Purpose Numerous techniques have been described for the tibial-sided graft preparation in anterior cruciate ligament (ACL) reconstruction. The use of less suture material for graft preparation is thought to improve ingrowth and to reduce the risk for infection. At the same time, the suture construct should be strong enough to resist the surgeon’s pull during tensioning of the transplant. Methods In total, 39 fresh-frozen procine deep flexor tendons were used and prepared as four-strand grafts. In the three-suture group ( n = 19), graft preparation was performed using three tibial-sided sutures, with each tendon end sutured separately. In the one-suture group ( n = 20), a modified graft preparation using only one tibial-sided suture was applied. Each sample underwent load-to-failure testing ( N _max) after cyclic pre-loading. To estimate intraoperative tension forces acting on the tibial-sided suture constructs, the maximal tension force of 26 volunteers on such a construct was measured using a load cell. Results The biomechanical testing of the two different suture constructs showed a significantly higher load-to-failure for the three-suture group (711 N ± 91 N) compared to the one-suture group (347 N ± 24 N) ( p = 0.0001). In both groups, the mode of failure was a tear of the suture in all samples. A failure of the suture–tendon interface was not observed in any case. The median maximal tension force on the construct applied by the 26 volunteers was 134 N (range 73–182 N). Conclusion The presented single-suture tendon graft preparation resisted to smaller failure loads than the conventional three-suture technique. However, no failures in the suture–tendon interface were seen and the failure loads observed were far beyond the tension forces that can be expected intraoperatively. Hence, the single-suture graft preparation technique may be a valuable alternative to the conventional technique.