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71.
目的 探索应用同种异体跟腱在重建前十字韧带 (ACL)的同时 ,重建受损的内侧副韧带 (MCL)的新方法 ,避免由自体取材造成的再损伤及由此引起的并发症。方法 首先在关节镜下应用经深低温冷冻处理的同种异体跟腱 ,采用等长重建、生物固定的方法 ,重建受损的ACL。然后在辅助切口下同时重建受损的MCL。结果  9例患者应用同种异体跟腱重建ACL和MCL ,全部病例获得了随访 ,采用Lysholm评分法评估患者手术前后的功能 ,术前平均 4 3 2分 ,术后平均 79 8分 ,优良率77 8%。客观检查 :前抽屉试验术前 9例阳性 ,术后均阴性 ;Lachman征术前 9例阳性 ,术后 1例弱阳性。膝外翻实验术前 9例阳性 ,术后均阴性。术后遗留膝关节疼痛 2例 ;膝关节活动受限 3例。结论 应用同种异体跟腱重建ACL ,可同时重建MCL。供材可提前制作 ,减少了自体取材造成的再损伤及其相应的并发症 ,该技术取材方便 ,手术方法简单 ,无需内固定物  相似文献   
72.
Inaccurate femoral tunnel placement has been identified as one of the most frequent errors in failed anterior cruciate ligament reconstructions. Most surgeons evaluate the femoral tunnel position on plain radiographs but in a lot of cases it is difficult to detect the femoral tunnel. The goal of this study was to compare plain digital radiographs and multiplanar computed tomography (CT) scans for the evaluation of femoral tunnel position. We examined 50 patients 24–60 months postoperatively, following an arthroscopically-assisted anterior cruciate ligament reconstruction with central third bone–patellar tendon–bone graft. Endobutton fixation was used on the femoral side and titanium interference screws on the tibial side. Standard antero-posterior and lateral X-rays and a CT scan were obtained from each patient. Sagittal and frontal reconstructions of the CT scan were used for the evaluation. We measured the height of the center of the tunnel in the notch in the frontal plane, and the position of the tunnel along Blumensaats line (BL) in the lateral plane. Measurements are reported as percentages of total notch height and of the length of BL. On plain X-rays the tunnel was invisible in 46 cases in the anterior–posterior plane and in eight cases on the lateral plane. The average position in the frontal plane was 89.8%, and in the lateral plane 38.6%. In the CT scans, measurements were able to be done in 48 patients. The frontal-plane position averaged 90.5% and the lateral-plane position 34.1%. Pearsons correlation coefficient for the values in the lateral plane for CT and X-rays was low at 0.22, with p>0.05. In our group of 50 patients we were able to detect the femoral tunnel on both plains of standard X-rays in only four patients, whereas it was possible to take accurate measurements in 48 patients on reconstructed CT scans. We advocate the use of CT technology for the evaluation of femoral position whenever precise measurements are needed.  相似文献   
73.
The tibial attachments of the individual anteromedial (AM) and posterolateral (PL) fibre bundles and the entire attachment of the anterior cruciate ligament are described, relating them to consistent bony landmarks; 55 fresh-frozen specimens were measured. The fibre bundles were separated and excised at their attachments and their peripheries marked with a pen. High-resolution scaled digital photographs were taken of each dissected specimen and transferred onto a computer for analysis. A wide variation was found when using the posterior tibial axis, the anterior tibial surface and the medial tibial spine as reference points. The most consistent measurements used the tibial interspinous “over-the-back” ridge as a datum. The attachments of the PL and AM bundles were centred 10 ± 1 mm (mean ± SD) and 17 ± 2 mm anterior to the over-the-back ridge. They were 4 ± 1 and 5 ± 1 mm, respectively, lateral to the medial tibial spine border. The positions of 6 mm circles in the posterior-medial limits of the fibre bundles (representing tunnels in a double-tunnel reconstruction) were measured. The overall dimensions of the tibial plateaux correlated significantly with many measurements. The results from this study could be used to guide ACL reconstruction techniques.  相似文献   
74.
The purpose of the present investigation was to evaluate physical outcome after anterior cruciate ligament (ACL) reconstruction with early versus late initiation of open kinetic chain (OKC) exercises for the quadriceps in patients operated on either patellar tendon or hamstring grafts. Sixty-eight patients, 36 males and 32 females, with either patellar tendon graft (34 patients) or hamstring graft (34 patients) were enrolled in this study. All patients were randomly allocated to either early (the 4th postoperative week) or late (the 12th postoperative week) start of OKC exercises for the quadriceps, resulting in four subgroups: patellar tendon reconstruction, early start (P4) or late start (P12) of OKC quadriceps exercises, hamstring tendon reconstruction, early start (H4) or late start (H12) of quadriceps OKC exercises. Prior to surgery and 3, 5 and 7 months later, assessments of range of motion (goniometer), anterior knee laxity (KT-1000), postural sway (KAT 2000), thigh muscle torques (Kin–Com dynamometer) and anterior knee pain (anterior knee pain score) were evaluated. No significant group differences were found in terms of range of motion 3, 5 and 7 months postoperatively. The H4 group showed a significantly higher mean difference of laxity over time of 1.0 mm (CI: 0.18–1.86) than the P4 group (P = 0.04). Within the same type of surgery, the H4 against the H12, the mean difference over time was 1.2 mm (0.37–2.1) higher in the H4 group than in the H12 group (P = 0.01). There were no significant group differences in terms of postural sway or anterior knee pain at the different test occasions. Significant differences in trends (changes over time) were found when comparing the four groups, for both quadriceps muscle torques (P < 0.001) and hamstring muscle torques (P < 0.001). All groups, except the P4 group, reached preoperative values of quadriceps muscle torques at the 7 months follow-up. In the H4 and the H12 groups, significantly lower hamstring muscle torques at the 7 months follow-up compared with preoperative values were found. In conclusion, early start of OKC quadriceps exercises after hamstring ACL reconstruction resulted in significantly increased anterior knee laxity in comparison with both late start and with early and late start after bone–patellar tendon–bone ACL reconstruction. Furthermore, the early introduction of OKC exercises for quadriceps did not influence quadriceps muscle torques neither in patients operated on patellar tendon nor hamstring tendon grafts. On the contrary, it appears as if the choice of graft affected the strength of the specific muscle more than the type of exercises performed. Our results could not determine the appropriate time for starting OKC quadriceps exercises for patients who have undergone ACL reconstruction with hamstring tendon graft. Future studies of long-term results of anterior knee laxity and functional outcome are needed.  相似文献   
75.
目的 观察等距和非等距前交叉韧带(anterior cruciate ligament,ACL)重建对膝关节功能的影响。方法 采用新鲜尸体观察等距ACL的解剖结构,在尸体和模型上重建等距和非等距ACL,分别观察重建后ACL长度和胫骨平台表面压强的变化。结果 等距ACL的重建在膝关节的全范围活动中长度的变化值最小,胫骨平台所受的压强也最小。结论 只有等距的ACI。的重建才能恢复膝关节的正常生理功能,而非等距重建的ACL会造成膝关节的不稳定(或活动受限),或者使膝关节表面的压强增加。  相似文献   
76.
77.
This study was performed to investigate the effects of changes in the skiing posture on mechanical stress across the knee joint. The aim of the present study was to establish a safer form of skiing for the prevention of injury to the anterior cruciate ligament of the knee (ACL). Ten healthy volunteers were placed on a force plate on an artificial slope, and assumed forward and backward bending postures with a single leg by changing their centre of gravity. The knee flexion angles were limited to approximately 30° by orthotics in each posture. Joint moments of the lower extremity were analyzed using a motion analysis system, and the muscle activities of the lower extremity were recorded by EMG and digitised to integrated EMG in each posture. In addition, extrusion of the lower leg by the boot was measured using a force sensor sheet inserted behind the calf. We found that the extension moment of the hip and ankle joints, and muscular activity of the hamstrings were increased in forward bending, whereas the extension moment of the knee and muscular activity of the quadriceps were decreased. Conversely, the muscular activity of the quadriceps, the flexion moment of the hip, extension moment of the knee joint, and pressure of the boot were increased in backward bending, whereas muscular activity of the hamstrings was decreased. The dependency on the hamstrings increased in forward bending in a skiing posture on a slope with slight knee flexion. Therefore, forward bending seemed to be an advantageous posture for the prevention of ACL injury. Conversely, in a backward bending skiing posture, the extension moment of the knee joint produced by muscle contraction of the quadriceps also increased imbalance in the hamstrings. The results of this study suggest that the internal force exerted by the quadriceps, in addition to the passive factor of extrusion of the lower leg by the boot, may contribute to non-contact ACL injury in a backward bending posture while skiing.  相似文献   
78.
The purpose of our study is to evaluate whether the hamstring tendons can regrow after harvesting for anterior cruciate ligament (ACL) reconstruction and whether the regenerate tissue can be histologically characterized as tendinous. Eleven of the patients (eight female and three male; mean age, 23 years; range 17–37 years) consented to participate in this study. One year after the ACL reconstruction, surgical biopsy was done. Regeneration of the tendon was detected macroscopically in 9 of the 11 patients. Histologically and immunohistochemically, the regenerated tendons closely resembled normal ones. The results of this study show the hamstring tendons can regenerate after harvesting for the ACL reconstruction.  相似文献   
79.
Press-fit fixation of patellar tendon bone anterior cruciate ligament autografts is an interesting technique because no hardware is necessary to achieve fixation. Up till the present point, there is no biomechanical data available for the tibial press-fit fixation of the hamstring tendons. Hamstring tendons of 21 human cadavers (age: 41.9 ± 13.1 years) were used. A press-fit fixation with looped semitendinosus and gracilis tendons secured by a tape (T) over a bone bridge, or by a baseball-stitched suture (S), was compared with degradable interference screw fixation (I) in 21 porcine tibiae. The constructs were cyclically strained and subsequently loaded to failure. The maximum load to failure, stiffness, and elongation during cyclical loading were measured. The maximum load to failure was highest for the T-fixation at 970 ± 83 N, followed by the I-fixation with 544 ± 109 N, and the S-fixation with 402 ± 78 N (P < 0.03). Stiffness of the constructs averaged 78 ± 13 N/mm for T, 108 ± 18 N/mm for S, and 162 ± 27 N/mm for I (P < 0.03). Elongation during initial cyclical loading was 2.0 ± 0.6 mm for T, 3.3 ± 1.1 mm for S, and 1.4 ± 0.5 mm for I (S inferior to I and T, P<0.05). Elongation between the 20th and 1,500th loading cycle was lower for T (2.2 ± 0.7 mm) compared with I (4.1 ± 2.7 mm) and S (4.8 ± 0.7 mm; P < 0.001). The T-fixation technique exhibited a significantly higher failure load than the S-, and I- techniques. All techniques exhibited larger elongation during initial cyclical loading than is reported in the literature for grafts with bone blocks. Only one technique (T) showed satisfactory elongation behavior during long-term cyclic loading. Interference screw fixation demonstrated significantly higher stiffness. Only one of the investigated techniques (T) seemed to exhibit adequate mechanical properties necessary for early aggressive rehabilitation programs.  相似文献   
80.
目的:探讨股骨外髁髁间侧壁软骨作为骨软骨移植术和软骨细胞移植术的取材部位的可行性.方法:回顾研究了235例膝前交叉韧带断裂行关节镜下韧带重建时的软骨损伤情况,分析了前交叉韧带断裂患者股骨外髁髁间侧壁软骨有无退变及其与髁软骨损伤、年龄、病程的关系.结果:本组235例患膝中,伴Ⅲ度以上软骨损伤占20%(其中伴髁间增生10例).Ⅲ度以上局限性软骨损伤而髁间侧壁非负重区软骨外观正常占15.74%.髁间侧壁非负重区软骨外观正常的Ⅲ度以上软骨损伤患者平均年龄为25.8岁,平均病程为16.75月;髁间侧壁非负重区软骨外观异常的Ⅲ度以上软骨损伤患者平均年龄为42.6岁,平均病程122.5月,后者明显大于前者,有显著性差异(t检验,P<0.02).结果提示,前交叉韧带断裂合并软骨损伤需要进行骨软骨移植时,可同时考虑在外髁髁间侧壁取材进行修复;ACL损伤后急性期和亚慢性期,关节镜下未见股骨外髁髁间侧壁软骨明显异常.自体骨软骨移植或自体软骨细胞移植治疗软骨损伤时,病程越短,供区所提供的骨软骨质量就越好,病程较长、年龄较大患者多发生膝骨关节炎,往往累及髁间侧壁,骨赘形成、髁间窝变窄,此时软骨的质量差,不能作为供区.  相似文献   
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