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91.
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Abstract The objective of the study was to evaluate the precision, concordance, practicability and the early clinical outcome of the use of a computerised navigation system in a comparative study with a group of 100 patients. Two groups of 50 patients each underwent implantation of a bicondylar knee prosthesis either by means of the freehand navigation system or by means of technical instrumentation. We found that the computerised navigation system provided a higher precision than the technically instrumented implantation: 94% of the prostheses implanted with the navigation system have an alignment within a range of -3° to 3° on of the Mikulicz line. Only 46% of the patients operated by means of the technical instrumentation reached this aspired result. Furthermore, the navigation system showed smaller ranges in the deviation of the aspired alignment. The radiological and computer-modeled alignment values differed both pre- and postoperatively, but to a larger extent before surgery. The varus or valgus deviations of the axis were more distinct radiologically under the weight of the patient’s body than in the computer model. The clinical outcome examined by the use of the HSS score after a mean followup of 7 months is good in both groups, and without significant differences. On average, the duration of surgery was 13 minutes longer in the computerised navigation group. We conclude that the benefit of the computerised navigation system is represented by the high improvement of precision. Achieving early clinical results identical to those in the technical instrumentation group, we expect a reduction of aseptic loosening in the computerised navigation group.  相似文献   
93.
微创与切开复位接骨板内固定治疗膝关节内骨折的比较   总被引:3,自引:3,他引:0  
[目的]比较研究微创接骨板内固定和切开复位接骨板内固定对膝关节内骨折的治疗效果,探讨生物学内固定在膝关节内骨折中的使用价值.[方法]总结近年来根据生物学固定原则,以微创接骨板固定术(MIPO)治疗的膝关节内骨折共21例.以创伤类型及年龄等因素进行配对,选择切开复位内固定(ORIF)治疗的病例资料比较手术及术后恢复情况.采用HSS评分评价结果.[结果]MIPO组随访10~16个月(平均14.2个月),有2例进行骨移植术,平均手术时间60.0 min,术中失血量45.0 ml,平均骨折愈合时间10.0周,3例有5°以上膝内、外翻畸形,HSS功能评分平均86.67分;ORIF组经过12~48个月(平均21.2个月)随访,有18例进行骨移植术,平均手术时间79.52 min,平均术中失血量117.1 ml,平均骨折愈合时间12.24周,2例发生5°以上膝关节内、外翻畸形,HSS功能评分平均82.14分.两组均获得骨愈合,没有感染和内固定断裂等并发症发生.比较发现两组患者在手术时间、术中失血量、骨折愈合时间和功能恢复方面差异有统计学意义.[结论]对于合适的膝关节内骨折病例以微创接骨板内固定治疗可以降低植骨需求和术中失血,在手术过程和术后恢复方面有明显优势.  相似文献   
94.
High tibial osteotomy changes the patella and tibial condyle position, which makes the subsequent total knee replacement technically demanding. From 1 January 1993 to 31 December 2000, combined osteotomy [After the first osteotomy made 2 cm distally to the joint line, a bone wedge is removed based laterally. Its tip ends at the center of the tibial condyle (half bone wedge). The distal part of the tibia is placed into the valgus position and the half bone wedge is placed into the gap opened medially.] was performed on 103 knees and closing wedge osteotomy was performed on 47 consecutive knees. Eighty combined (group A) and 41 closing wedge (group B) osteotomy were studied. All knees were assessed radiologically before surgery, in the 10th postoperative week, in the 12th postoperative month and at the time of the final follow-up (in group A—66.15 months, in group B—66.61 months). We examined the change of the femorotibial angle, of the patellar height according to the method of Insall and Salvati, of the tibial slope angle according to the method of Bonnin, of the tibial condylar offset according to the method of Yoshida and of the distance between the lateral tibial plateau and the top of the fibular head. In group A and B, the recurrence of the varus deformity was not noted and valgus alignment did not increase in any case. In group-A, the Insall–Salvati ratio remained unchanged in 65% of knees. The tibial slope angle decreased in both groups. There was correlation between the change of the tibial condylar offset and the angle of the correction in both groups. There was correlation between the change of the distance between the lateral tibial plateau and the top of the fibular head. After combined osteotomy, the transposition of the tibial condyle and the decrease of the distance between the lateral tibial plateau and the top of the fibular head was less than after closing wedge osteotomy, although the average angle of correction was more after combined osteotomy (11.835°), than after closing wedge osteotomy (9.465°). Theoretically, the recurrence of the varus deformity, the increase of the valgus alignment and (in majority of cases) the shortening of the patellar tendon do not compromise the likelihood of successful conversion to the subsequent total knee replacement, either after combined or after closing wedge osteotomy. The combined osteotomy does not lead to considerable transposition of the tibial condyle and to considerable lateral tibial bone loss; therefore, theoretically, the combined osteotomy does not impair the subsequent total knee replacement.  相似文献   
95.
The purpose of the study was to evaluate the mid-term results of surgical treatment in different groups of patients with multiple knee ligament injuries. Review of our patients’ records revealed that 48 acute and chronic patients were surgically treated for combined knee injury. Due to severe capsular damage in these injuries, open techniques were used. In our treatment protocol, avulsed ligaments and tears of the posterolateral and posteromedial corner were repaired if possible, whereas midsubstance tears of cruciate ligaments and chronic cases were reconstructed with autografts. Postoperatively, an accelerated program of rehabilitation was introduced, aiming to progressively mobilize the joint and improve muscle endurance. For the follow-up evaluation we designed a protocol composed of two parts. In the first part, anatomical lesions were recorded and in the second part, clinical evaluation was performed using the Lysholm score, the Tegner rating system, the IKDC evaluation form, and the KT1000. Student’s t tests and chi-square tests were used for data analysis. Forty-eight patients (mean age 28.6±11.9 years; 41 males) were classified according to the specific anatomical structures involved. Group A included 12 anterior cruciate ligament (ACL) and medial structure injuries, group B included 11 ACL or posterior cruciate ligament (PCL) ruptures combined with posterolateral injuries, and group C consisted of 25 knee dislocations (ACL and PCL ruptures which might be combined with damage of the collateral ligaments). Thirty-eight patients were surgically treated during the acute phase and ten patients were treated chronically. Forty-four patients (91.6%) were followed up at a mean of 51.3±29.9 months. Average Lysholm score was 87±12.3; average Tegner score was 5.09±2.19 before accident and 4.34±2.12 in re-examination; IKDC score was A in 10 cases, B in 22, C in 6, and D in 6. The mean range of motion was 129.9°±12.5°. The average loss of extension and flexion were 1.6°±2.5° and 7.6°±7.9°, respectively. The side-to-side difference in corrected anterior and posterior translation in quadriceps neutral angle and in anterior translation in 30° angle was <3 mm for about 65% of our patients. Surgical treatment of multiple knee ligament injuries, using autografts, provided satisfactory stability, range of motion, and subjective functional results. However, despite the improvement of the quality of life, the preinjury patients’ activity level was not fully obtained in re-examination. Patients underwent surgical treatment during the acute phase had better scores in several points, but finally there was no statistical significance between acute and chronic patients. Moreover, no statistically significant differences were observed among the groups with specific damaged anatomical structures.  相似文献   
96.
目的探讨体表面积(BS)、体质量、体质量指数(BMI)对老年人骨密度(BMD)的影响。方法用双能X线骨密度仪测定1794例老年人腰椎、髋关节的BMD值,并对其与BS等指标进行相关回归分析。结果BS大的老年人其BMD大于BS小者,有显著性差异。在各种指标与BMD的相关性比较中,BS与BMD的相关性最好,其后依次为:体质量、身高、OSTA得分(亚洲人自我骨质疏松筛查工具)、BMI。结论BS比BMI等指标更能反映出人体体型对老年人BMD的影响。  相似文献   
97.
计算机导航辅助下人工全膝关节置换术   总被引:3,自引:0,他引:3  
目的通过分析计算机导航辅助下人工全膝关节置换术中定位与软组织平衡的辅助检测作用,与传统手术进行疗效差异的比较,探讨计算机导航辅助手术的安全性、可靠性及其优势与不足。方法自2004年10月至2005年10月行计算机辅助人工全膝关节置换术18例22膝(导航组),男7例8膝,女11例14膝;年龄35~74岁,平均67岁。导航组采用计算机辅助下行人工全膝关节置换手术。从2003年10月至2004年10月用传统手术的52例中随机抽取17例22膝(非导航组),男5例6膝,女12例16膝;年龄56~78岁,平均65岁。非导航组采用髓内定位杆(股骨)、髓外定位杆(胫骨)定位,常规手术行人工全膝关节置换。全部44膝均为初次置换,两组患者的原始疾病、年龄、HSS评分行配对t检验,差异无统计学意义(P>0.05)。对比两组术前、术后的力线、软组织平衡、并发症、出血量、手术时间及随访情况,进行统计学处理。结果全部病例随访3~12个月,平均10个月。导航组力线误差大多在2°~3°,非导航组3°~6°。软组织平衡角度变量导航组大多在2°以内,非导航组2°~4°;软组织平衡分离变量导航组大多在2~4mm,非导航组5~7mm。导航组出血量大多在550~700ml,非导航组700~900ml;导航组手术时间大多在75~100min,非导航组45~60min。经SPSS10.0统计软件处理,两组在术后力线、软组织平衡角度变量和分离变量、出血量、手术时间,其差异均有统计学意义(P<0.05)。结论计算机导航辅助人工全膝关节置换术,使假体的植入位置更为准确,术后下肢力线和软组织平衡更佳,并能减少出血量,早期疗效满意,但延长了手术时间。  相似文献   
98.
早期扩髓髓内钉固定治疗合并胸部损伤的股骨干骨折   总被引:2,自引:0,他引:2  
目的探讨合并胸部损伤的股骨干骨折早期扩髓及髓内钉固定是否增加并发症及死亡率. 方法采用回顾性对比分析,依据下列标准选择病例(1) 年龄在17~65岁;(2) 必须有胸部损伤[简明损伤定级(AIS)≥2], 且损伤严重度评分(ISS)≥16;(3) 住院时间≥48 h;(4) 病史中无明显影响全身状况的疾病, 如糖尿病, 慢性心、肺、肾功能不全等;(5) 有股骨干骨折, 且进行了扩髓髓内钉固定, 不含钢板、外固定支架或牵引及石膏固定者.并按受伤至手术时间划分为两组, A组为<24 h手术者(早期扩髓组), B组为≥24 h手术者(延期扩髓组),将两组间合并伤情况、ISS、住院时间、ICU时间、并发症、死亡及合并休克情况进行比较. 结果有96例符合上述标准, 其中A组57例, B组39例,经统计学处理, 两组间仅在股骨开放性骨折发生率(A组53%,B组31%,χ2=4.496, P<0.05)、合并休克率(A组51%, B组28%,χ2=4.895, P<0.05 )及住院时间[A组为(17.5±6.5)d, B组为(31.5±9.5)d,t=8.599, P<0.001]上差异有显著性意义和非常显著性意义, 而两组并发症发生率和死亡率等方面比较, 差异无显著性意义(P>0.05). 结论在合并胸部损伤的股骨干骨折中,只要能控制休克,保证生命体征平稳,对股骨干骨折行早期扩髓髓内钉固定不增加患者的并发症发生率及死亡率,并可促进患者早日康复,缩短住院时间.  相似文献   
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