全膝置换术后的髌腱短缩及其临床影响

目的研究全膝置换(totalkneearthroplasty,TKA)术后的髌腱长度变化,置换髌骨对髌腱长度的影响,髌腱长度变化与术后膝关节活动度的关系。方法2002年5月~2003年12月对49例55个关节行初次全膝置换手术。包括48例骨关节炎、7例类风湿性关节炎,其中7例做了外侧支持带松解,测量术前的髌腱长度及术后1年的髌腱长度和膝关节活动度,按是否置换髌骨分成两组,对数据进行组间和组内统计学分析。结果术后1年,髌腱发生有统计学意义的短缩(P<0·01)。在短缩大于10%的发生率上,换与不换髌骨组没有统计学意义的差别(P>0·05)。髌腱短缩和关节活动度呈负相关(P<0·01)。结论全膝置换术后存在髌腱短缩的并发症。置换髌骨对髌腱短缩没有影响。髌腱短缩可能是导致术后活动度损失的原因之一。     

全膝关节置换术中关节后方复合松解对术中关节间隙变化及改善术后活动度的影响

目的观察全膝关节置换术中关节后方复合松解对术中关节间隙及改善术后活动度的影响。方法随机将90例接受全膝关节置换术的患者分为2组,各45例。对照组于截骨后行后髁增生骨常规清理,观察组在对照组基础上行关节后方复合松解。比较2组患者术中屈、伸膝间隙及术后最大屈膝角度、平均屈膝角度、主动屈膝90°及120°时间。结果 (1)术中2组屈膝间隙比较,差异无统计学意义(P0.05);观察组伸膝间隙大于对照组,差异具有统计学意义(P0.05)。(2)术后2组平均屈膝角度均大于术前,但观察组优于对照组,差异有统计学意义(P0.05)。(3)观察组最大屈膝角度大于对照组,主动屈膝90°及120°时间均小于对照组,差异有统计学意义(P0.05)。结论全膝关节置换术中关节后方复合松解可有效改善术中关节间隙及术后活动度。     

在全膝关节置换术中保留和切除髌下脂肪垫对髌腱长度的影响

目的 研究在初次全膝关节置换术中,保留和切除髌下脂肪垫对髌腱长度的影响.方法 将67例骨性关节炎患者(99膝),分为A、B两组.A组为保留髌下脂肪垫组(51膝),B组为切除髌下脂肪垫组(48膝).拍摄膝关节X-ray侧位片:患者仰卧位,半屈膝(＞30°),并确认髌腱为紧张状态.于膝关节侧位片上定位髌骨下极髌腱附丽点和胫骨结节上方凹陷,测量其两点直线长度,即为髌腱长度.测量术前及术后随访时髌腱的长度.结果 A组术前及术后随访时髌腱的长度差异无统计学意义,B组术前及术后随访时髌腱的长度差异有统计学意义(t检验,P=0.0083).结论 在全膝关节置换术中,切除髌下脂肪垫是引起髌腱短缩的重要因素之一,已成为全膝关节置换术后的潜在的、难以察觉的并发症.     

全膝关节置换术治疗膝骨关节炎合并固定性髌骨脱位

目的评估全膝关节置换术治疗膝骨关节炎合并固定性髌骨脱位患者的临床疗效。方法对6例膝骨关节炎合并固定性髌骨脱位的患者(8膝)行全膝关节置换术。采用标准内侧髌旁入路,并行“+”形松解外侧支持带,常规髌骨置换,使用非限制性后稳定假体。比较手术前后的HSS评分和疼痛VAS评分,测量股骨胫骨角(FTA)和伸膝迟滞。结果患者均获得随访,时间1~8年。HSS评分从术前25~63分提高到术后1年75~94分。VAS评分从术前5~8分下降至术后1年0~3分。FTA从术前161°~173°改善至术后1年173°~175°。术前有10°~25°的伸膝迟滞,术后基本消失。结论采用标准内侧髌旁入路结合外侧结构的松解作全膝关节置换术治疗膝骨关节炎合并固定性髌骨脱位可获得良好的临床疗效。     

严重膝外翻全膝关节置换治疗的疗效观察

目的 探讨全膝关节置换术治疗严重膝外翻畸形的手术方法和临床疗效.方法 2010年3月至2011年12月,对18 例（25膝）严重膝外翻患者进行全膝关节置换.术前X线测量股胫角（femorotibial angle,FTA）,检查膝关节活动度,进行HSS评分.手术采用髌旁内侧入路、常规截骨、选择性的外侧软组织松解、安装后稳定型假体或半限制型假体进行全膝关节置换术.术后测量FTA角,术后定期随访检查膝关节活动度并行HSS评分.结果 所有患者均获得随访,随访时间3～24个月.FTA角由术前的25.5°（18°～39°）降低至4.7°（1°～8°）;膝关节活动度由术前的72.1°（67°～95°）提高到107.3°（100°～120°）;HSS评分由术前的24.5分（16～38分）提高到89.3分（84～96分）,差异均有统计学意义（P＜0.01）.结论 对于严重膝外翻畸形的患者,采用髌旁内侧入路、常规截骨、选择性的外侧软组织松解、安装后稳定型的假体或半限制型假体实施人工全膝关节置换术治疗,能够取得满意的临床效果,可以明显改善患者膝关节的功能,提高患者的生活质量.     

全膝关节置换术中髌骨假体内置的临床研究

目的探讨髌骨置换时髌骨假体内置对髌股关节运动轨迹的影响。方法2001年9月～2002年3月48例(75膝)行全膝关节置换患者,采用髌骨假体内置的方法置换髌骨,并在术中髌骨置换前后测试髌股关节运动轨迹,术后对患者进行随访。观察髌骨假体安放位置对髌股关节运动轨迹及术后关节功能的影响。结果75膝术中胫骨、股骨截骨完成并安装试模后测试髌股关节运动轨迹,69膝可达到“nothumbtest”,髌骨内置2～5mm后再次测试仍全部达到“nothumbtest”;余6膝未达到“nothumbtest”,经髌骨内置4～8mm后5膝达到,1膝经髌外侧支持带松解最终实现“nothumbtest”。术后经12～18个月随访,膝关节活动度平均为116.5°(95°～125°)。无一例出现髌骨脱位、半脱位、髌骨坏死、髌骨骨折、髌腱撕脱、髌骨不稳以及皮肤坏死等并发症。结论在全膝关节置换术中,髌骨假体内置可有效地改善髌股关节运动轨迹,减少对髌外侧支持带松解的需求,降低髌骨相关的并发症。     

关节镜下内侧紧缩及外侧松解加半髌腱止点移位术治疗复发性髌骨脱位

目的 评价微创关节镜下外侧松解、内侧紧缩、半髌腱止点移位术的三联手术方案治疗复发性髌骨脱位的临床疗效.方法 以1998～2008年收治的71例（77膝）复发性髌骨脱位患者为研究对象,入选标准为：胫骨骨骺已经闭合,且股骨滑车沟无严重发育不良和严重膝外翻畸形.男11例,女60例;平均年龄19.5岁,67例有明确外伤史.术前测量Q角.Merchant位X片上测量股骨滑车沟角、髌骨-股骨滑车适合角,髌股外侧角.CT平扫测量股骨髁滑车凹中心与胫骨结节水平距离（TT TG）.术中采用外侧松解、内侧紧缩和半髌腱止点移位三联手术方案.结果 2例（2膝）失访,69例（75膝）术后随访2～12年,平均5.2年.除早期1例患者在术后2个月再次发生髌骨脱位外,其余病例术后髌骨脱位未见复发.术前髌骨-股骨滑车适合角（24.2°±6.8°）,术后为（-2.1°±5.8°）（P〈0.05）;术前髌股外侧角（-2.0°±5.2°）,术后为（10.9°±4.0°）（P〈0.05）;术前TT TG平均为（19.8±2.1） mm,术后为（13.6±1.8） mm （P〈0.01）.术前Lysholm评分和IKDC评分分别由术前的（45.6±4.8）、（48.3±6.8）分,提高到术后的（92.3±10.8）分 （P〈0.05）和（94.3±8.4）分（P〈0.05）;术前测量Q角男性平均为（13.2°±3.1°）,术后平均为（9.2°±2.8°）（P〈0.05）;女性平均为（21.0°±5.2°）,术后平均为（15.4°±4.4°）（P〈0.05）.结论 关节镜下外侧松解、内侧紧缩缝合、半髌腱移位术的综合手术方案治疗复发性髌骨脱位创伤较小,疗效确切,术后患者膝关节功能改善明显,手术操作简便,易于掌握.     

全膝关节置换术中股骨假体屈曲对髌股关节生物力学影响的实验研究

[目的]探讨全膝置换术中股骨假体矢状位上屈曲对髌股关节生物力学的影响,为临床指导人工膝关节置换的手术技术提供实验依据,以减少术后髌股关节的并发症。[方法]取正常国人新鲜冷冻尸体的5个膝关节作为研究对象,模拟膝关节自站立位屈膝下蹲的动作,设计制作膝关节实验架,与生物力学测试仪共同搭建实验平台。人工膝关节采用DePuy PFC假体全膝系统,手术由同一位有经验的术者实施以控制实验误差,置换髌骨。比较股骨假体相对于按下肢力线位、前屈5°、10°及后屈5°、10°、15°位置时的髌股关节的生物力学指标。选择屈膝30°、60°、90°、120°为观察角度,采用美国Tecscan公司生产的感测片测定髌股关节接触压峰值,最后软件处理得到数字化的结果。[结果]除了在膝关节屈曲30°、60°、90°,股骨假体前屈5°时,髌股关节内侧间隙接触压峰值与下肢力线位相比较无显著性差异(P>0.05),其余各种屈膝角度下,股骨假体不同屈曲角度所致髌股关节内外侧间隙接触压峰值与下肢力线位比较有显著性差异(P<0.05)。股骨假体后屈角度越大,峰值的升高越明显。[结论]全膝关节置换术中,股骨假体在矢状位上争取按下肢力线位置入,以降低术后并发症的发生。     

Wiberg分型对保留髌骨TKA术后髌骨轨迹及功能的影响

目的研究全膝关节置换术(total knee arthroplasty,TKA)对髌骨形态、术后轨迹及术后功能的影响。方法选取2016年1月到2017年1月因膝关节骨关节炎行TKA的患者共76例(81膝),男21例(22膝),女55例(59膝);年龄53～77岁,平均(66.19±6.83)岁。于屈膝45°、投射角度30°的数字化X线成像系统上拍摄膝关节髌骨轴位片,使用Wiberg标准评估髌骨分型并测量髌骨倾斜角、髌股指数、髌股适合角。术中保留髌骨,对髌骨周边骨赘进行清除,保持正常的髌骨解剖形态。术前Wiberg分型Ⅰ型18膝,Ⅱ型49膝,Ⅲ型14膝。比较不同Wiberg髌骨分型手术前后的影像学指标、美国特种外科医院(the hospital special surgery,HSS)功能评分、髌骨评分、上下楼评分、膝前痛视觉模拟评分(visual analogue scale,VAS)。结果术后患者均获随访,随访时间均两年以上,平均随访时间(25.16±6.24)个月。髌骨倾斜角由术前(-10.04±4.74)°减小为术后(-7.54±4.61)°,差异具有统计学意义(P=0.000);髌股指数由术前(1.50±0.54)减小为术后(1.17±0.59),差异具有统计学意义(P=0.047)。术前WibergⅠ型髌骨倾斜角(-11.05±5.6)°,Ⅱ型(-8.74±5.6)°,Ⅲ型(-13.22±3.72)°,差异有统计学意义(P=0.013);术前WibergⅠ型髌骨髌股指数(1.53±0.53),Ⅱ型(1.35±0.47),Ⅲ型(1.95±0.58),差异有统计学意义(P=0.004)。WibergⅡ型的患者术前髌骨倾斜角及髌股指数较其他两型要小。术前不同Wiberg髌骨分型的髌股适合角度差异有统计学意义(P=0.006)。不同Wiberg分型的患者术后髌骨倾斜角(P=0.117)、髌股指数(P=0.058)、髌股适合角度(P=0.572),差异无统计学意义(P0.05)。不同Wiberg分型的患者术后HSS评分(P=0.572)、美国膝关节协会评分(knee society score,KSS)(P=0.657)、KSS功能评分(P=0.066)、髌骨评分(P=0.102)、上下楼评分(P=0.080)、VAS评分(P=0.332)差异无统计学意义。结论全膝关节置换术中,通过髌骨成形及外侧支持带松解可达到良好的术后髌骨轨迹及临床疗效。Wiberg髌骨形态对保留髌骨型全膝关节置换术后功能无明显影响。     

初次全膝关节置换术后膝关节僵硬的相关因素分析

[目的]探讨初次全膝关节置换术后膝关节僵硬的发病率和影响因素.[方法]1996年10月～2006年10月回顾性研究1 216例初次全膝关节置换术.术后1年45例膝关节屈曲度<90°的患者做为实验组,45例膝关节屈曲度>90°的患者作为对照组.两组根据年龄、性别、体重指数(BMI)和美国麻醉分级(ASA)等进行配对病例对照研究分析影响因素.[结果]两组患者平均年龄、性别比例及术前合并症比较,差异无统计学意义.术前(P=0.001)和术中(P=0.039)膝关节屈曲度与术后膝关节屈曲度比较,差异有统计学意义.术前和术后髌骨低位与术后膝关节僵硬发生呈明显相关性(P=0.001).[结论]初次全膝关节置换术后膝关节僵硬受多种因素影响,选择合适的患者、术中仔细暴露、重建伸屈膝间隙、减少髌腱和伸膝装置的损伤、选择合适假体、保持良好的下肢力线和术后理疗等因素会明显减少膝关节僵硬的发病率.     

Arthroscopic treatment of patellar clunk.

Excellent results have been reported with posterior stabilized total knee arthroplasty. A common complication relating to patellofemoral articulation is patellar clunk syndrome. Patellar clunk syndrome occurs when a fibrous nodule develops just proximal to the patellar button. At approximately 30 degrees to 45 degrees from full extension, the nodule catches the anterior flange of the femoral prosthesis, resulting in the clunk and a painful range of motion. The present study examines the use of arthroscopic debridement for this disorder. Thirty consecutive patients (32 knees) with the diagnosis of patellar clunk syndrome were evaluated at 1 year after arthroscopic debridement. All patients were evaluated clinically and radiographically according to the Knee Society score. In addition, patients were questioned specifically regarding anterior knee pain and patellofemoral symptoms. Radiographs were evaluated further regarding patella and component position. Patients were diagnosed with patellar clunk at an average of 12 months after their latest knee arthroplasty, with a range of 3 to 47 months. All patients complained of anterior knee pain and the clunk. All patients had a hypertrophic nodule at the junction of the proximal pole of the patella and quadriceps tendon and underwent arthroscopic debridement through a superolateral portal. All patients were free of patellar clunk postoperatively; one patient reported persistent anterior knee pain. Knee Society scores increased from an average of 64 points preoperative to 93 points postoperative. Radiographs showed patella alta in eight knees, patella baja in two. Four femoral components were in 5 degrees flexion. The present study represents the largest collection of data regarding patellar clunk syndrome. The data appear to support arthroscopic debridement as a successful treatment of patellar clunk syndrome.     

Intraoperative patellar tendon strain: predicting the range of knee flexion after total knee arthroplasty

Background  The preoperative range of motion is an important factor that influences the range of motion after total knee arthroplasty. Because the length and tightness of the extensor mechanism are extracapsular elements with an influence on knee flexion, it is reasonable to assume that the tension of the knee extensor mechanism during surgery has a considerable impact on the postoperative range of motion. The purpose of this study was to determine the influence of the tightness of knee extensor mechanism on postoperative knee flexion. Methods  In 18 knees undergoing posterior-stabilized type total knee arthroplasty, we measured the longitudinal strain on the patellar tendon with all the components in position during passive knee flexion up to 135°. The patellar tendon strains measured during surgery were compared with the preoperative maximum knee flexion angle and postoperative maximum knee flexion angle at 1 year. Results  There was a significant inverse correlation between the patellar tendon strain during surgery at 60° (r = -0.54, P < 0.05), 90° (r = -0.55, P < 0.05), or 135° of flexion (r = -0.65, P < 0.05) and postoperative knee flexion. Conclusions  The results indicated that subjects with high intraoperative patellar tendon strain during passive flexion of the knee had more restricted postoperative knee flexion. Therefore, the tightness of the knee extensor mechanism measured at total knee arthroplasty is a good predictor of maximum postoperative range of flexion.     

Factors affecting range of flexion after total knee arthroplasty

Many factors affect postoperative range of flexion after total knee arthroplasty (TKA). The purpose of this study was to identify the most important factors that affect range of knee flexion after TKA. Sixty-five patients (73 knees) were treated with Genesis II knee replacements. Minimum follow-up was 2 years. Patient demographics (sex, age, body mass index, previous surgery, component type, patella resurfacing, preoperative Knee Society score preoperative range of motion) and radiographic measurements (preoperative tibiofemoral varus/valgus angle, height of the joint line, length of the patellar tendon, shift and tilt angle of the patella) were analyzed statistically. Among these factors, preoperative range of flexion, positively, and preoperative varus/valgus tibiofemoral angle, negatively, affected postoperative range of flexion. The tilt angle of the patella and the tilt angle of the patellar button approached statistical significance in revealing a negative relation with postoperative range of flexion. TKAs in which the patella was not resurfaced tended to lose range of flexion, whereas TKAs in which the patella was resurfaced tended to have no loss of flexion, although the number of TKAs in which the patella was not resurfaced was small. In conclusion, preoperative range of flexion and preoperative varus/valgus tibiofemoral angle affected postoperative range of flexion. The tilt angle of the patella and tilt angle of the patellar button may be factors that affect postoperative range of flexion. Received: September 28, 2000 / Accepted: January 9, 2001     

Patellar tendon rupture repair using Dall-Miles cable

Ten patients underwent patellar tendon repair with end-to-end suture technique and medial and lateral retinacular repair, as well as reinforcement with a Dall-Miles cable through the patella and tibial tubercle. The cable was tensioned at 60 degrees of flexion to allow immediate range of motion to at least 100 degrees of flexion and to protect the repair from undue tension while healing. Accurate tendon length was obtained from a lateral radiograph of the noninvolved knee in 60 degrees of flexion. Patients were allowed to bear full weight as tolerated postoperatively. A knee immobilizer was worn for approximately 2 weeks when adequate muscular control of the leg was attained. The cable was removed 6-8 weeks postoperatively, at which time range of motion equal to the opposite extremity was sought. Full extension was obtained by 1 week postoperatively. Average postoperative knee flexion was 88 degrees at 2 weeks, 112 degrees at 1 month, 133 at 3 months, and 138 degrees at 6 months compared to flexion of 141 degrees in the noninvolved knee. Mean quadriceps muscle strength 1 year postoperatively was 72%+/-11% of the noninvolved leg. No patient had patella infera or rerupture after surgery. Repair of a patellar tendon rupture with end-to-end techniques reinforced with a Dall-Miles cable allows immediate rehabilitation without the need for prolonged immobilization. This technique allows restoration of full range of motion early postoperatively and enables patients to regain adequate quadriceps strength.     

Q-angle influences tibiofemoral and patellofemoral kinematics.

Numerous surgical procedures have been developed to correct patellar tracking and improve patellofemoral symptoms by altering the Q-angle (the angle between the quadriceps load vector and the patellar tendon load vector). The influence of the Q-angle on knee kinematics has yet to be specifically quantified, however. In vitro knee simulation was performed to relate the Q-angle to tibiofemoral and patellofemoral kinematics. Six cadaver knees were tested by applying simulated hamstrings, quadriceps and hip loads to induce knee flexion. The knees were tested with a normal alignment, after increasing the Q-angle and after decreasing the Q-angle. Increasing the Q-angle significantly shifted the patella laterally from 20 degrees to 60 degrees of knee flexion, tilted the patella medially from 20 degrees to 80 degrees of flexion, and rotated the patella medially from 20 degrees to 50 degrees of flexion. Decreasing the Q-angle significantly tilted the patella laterally at 20 degrees and from 50 degrees to 80 degrees of flexion, rotated the tibia externally from 30 degrees to 60 degrees of flexion, and increased the tibiofemoral varus orientation from 40 degrees to 90 degrees of flexion. The results show that an increase in the Q-angle could lead to lateral patellar dislocation or increased lateral patellofemoral contact pressures. A Q-angle decrease may not shift the patella medially, but could increase the medial tibiofemoral contact pressure by increasing the varus orientation.     

Patellofemoral kinematics during knee flexion-extension: an in vitro study.

The purpose of this work was to obtain kinematics data for the normal human patellofemoral joint in vitro. Eight fresh-frozen cadaver knees were used. The heads of the quadriceps were separated, and the knees mounted in a kinematics rig. The femoral axis was aligned with an electromagnetic transmitter. The six heads of the quadriceps, including vasti medialis and lateralis obliquus, were loaded via cables according to their physiological cross-sectional areas and orientations. Magnetic trackers were mounted on the patella and tibia. The knee was flexed-extended against the extending muscle action, and patellar tracking was measured in six degrees of freedom. As the knee flexed, the patella flexed by 0.7 times the tibiofemoral flexion angle. It also translated medially 4 mm to engage the trochlear groove at 20 degrees knee flexion, then translated to 7 mm lateral by 90 degrees knee flexion. The patella tilted progressively to 7 degrees lateral by 90 degrees knee flexion, and patellar medial-lateral rotation was usually less than 3 degrees. This is believed to be the first set of patellar tracking data obtained in both flexion and extension motion while the patella was acted on by a full set of quadriceps muscle tensions acting in physiological directions. These data may be used in future studies of the effects of pathologies on patellar tracking.     

Patellofemoral joint after total knee arthroplasty: Effect on contact area and contact stress

Compressive contact stress between the patella and the anterior femur and between the quadriceps tendon and anterior femur was measured before and after total knee arthroplasty in 5 cadaver knee specimens using a digital electronic sensor. Contact stresses were measured in the normal knee and after total knee arthroplasty with an unresurfaced patella, a dome-shaped patella, and a conforming patella. Patellofemoral contact stresses did not change significantly after total knee arthroplasty when the patella was not resurfaced, but they increased significantly after the patella was resurfaced with both the dome-shaped and the conforming components. The conforming patella had the highest contact stresses because it tilted at flexion angles greater than 90° and applied load to a small area on the superior portion of the patellar component. The conforming patella markedly decreased tendofemoral contact force because the thicker superior pole of the patella tented the quadriceps tendon at flexion angles greater than 120°. This further increased patellofemoral contact force in deep knee flexion.     

人工全膝关节置换术治疗膝关节伸直位强直畸形

目的探讨膝关节伸直位强直畸形患者行人工全膝关节置换术的手术要点和术后效果。方法1996年1月至2006年6月,对8例（9膝）膝关节伸直位强直畸形患者行人工全膝关节置换术。术前膝关节活动度均为0°,KSS膝关节评分平均为44分（10～68分）,功能评分平均为17分（-10～55分）。结果8例患者（9膝）围手术期出现的并发症包括髌腱止点撕脱1膝,髌骨下极部分撕脱骨折1膝,术后早期关节血肿1膝,皮肤浅表性感染1膝,经对症治疗后所有患者均治愈出院。术后平均随访40．4个月（7．0～120．0个月）,术后膝关节平均活动度89°（50°～120°）,术后KSS膝关节评分平均为81分（55～93分）,功能评分平均为79分（50～90分）。2例2膝分别存在5°和25°的伸展滞缺。1例1膝因为关节不稳于术后1年行翻修术,更换加厚的胫骨平台垫片。结论膝关节伸直位强直畸形患者行人工全膝关节置换术难度大,并发症发生率较高,但如能恰当处理,仍可以取得较满意的临床效果。术中膝关节的充分暴露,保留足够的髌骨床厚度,保护髌腱和膝关节的血液供应以及正确的软组织平衡技术是手术的关键。