股骨远端旋转力线定位标志研究进展

目的综述人工全膝关节置换术中股骨远端旋转力线定位标志的研究进展。方法广泛查阅近年国内外股骨远端旋转力线相关文献,并对其进行综合分析。结果若假体旋转力线对位不良将导致诸如髌骨脱位、弹响、磨损、髌前疼痛等多种髌股关节并发症。人工全膝关节置换术中确定股骨假体旋转力线的方法较多,常用方法包括股骨上髁轴线、前后轴线、股骨后髁线、屈曲间隙平衡技术、计算机导航技术等。正确选择旋转力线,对减少术后并发症和降低假体翻修率均至关重要。目前人工全膝关节置换术中选择合适的参照轴以保证股骨假体旋转力线对位的准确性仍有争议。结论股骨假体旋转力线是影响人工全膝关节置换术预后极其重要的环节。确定股骨假体旋转力线的方法有待进一步改进。     

全膝关节置换术股骨远端相关解剖的研究进展

全膝关节置换术(total knee arthroplasty,TKA)能够有效的恢复膝关节生理力线、解除膝关节疼痛、恢复膝关节正常的功能,是治疗终末期膝骨性关节炎的有效的方法[1～3]。拟行TKA的患者通常伴有股骨远端解剖标志不清和形态的改变。TKA术中股骨假体的旋转力线是影响术后膝关节功能和假体使用寿命的重要因素,股骨假体旋转不良可导致术后髌骨轨迹异常、膝前区疼痛、胫股假体部件间剪切扭转应力增加和屈膝不稳定等[4-5]。因此如何精确定位股骨远端各     

正常及骨性关节炎膝关节股骨远端旋转对线MRI比较研究

目的对正常及内翻畸形骨性关节炎膝关节行MRI测量,探讨股骨远端旋转对线的变化以指导临床。方法 MRI扫描60侧正常膝关节(A组)、40侧轻度(B组)及20侧重度(C组)内翻畸形骨性关节炎膝关节,MRI上定位STEA、CTEA、PCL、WL、AFA为骨性标志物,测量并比较3组CSA、PCA、CTA、WSA、WCA、AFSA、AFCA。结果 3组间CSA、WSA、WCA、AFSA、AFCA比较差异无统计学意义(P>0.05)。A组与B组、B组与C组的PCA、CTA比较差异无统计学意义(P>0.05),但A组与C组的PCA、CTA比较差异有统计学意义(P<0.05)。结论重度内翻畸形骨性关节炎影响股骨PCA及CTA,两者在C组有所减小;WSA、WCA不受骨性关节炎的影响,但角度变异较大,不能只用WL决定股骨假体的旋转;AFSA、AFCA不受骨性关节炎的影响,两者变异小(标准差为2.18°及2.38°),参照该轴放置股骨假体较可靠。     

CT扫描确定全膝关节置换股骨假体旋转力线的研究

目的探讨术前CT扫描对全膝关节置换(TKA)中股骨假体旋转力线精确确定的作用。方法将200例(252膝)TKA患者随机分为两组:①经验组(64例):TKA术中根据术者触摸外科股骨上髁轴线联合Whi-teside线联合确定股骨假体外旋角度;②CT扫描组(136例):术前CT扫描确定股骨后髁角,术中采用可调外旋定位器复制CT确定的外旋角度,其余TKA手术操作相同。两组术后均行CT扫描确定股骨假体旋转不良角度并对其绝对值进行比较。结果经验组TKA术后股骨假体旋转不良角度为2.8°±0.14°,CT扫描组为1.2°±0.04°,两组比较差异有统计学意义(t=4.18,P<0.01)。经验组股骨假体旋转不良率为32.1%,CT扫描组为18.5%,两组比较差异有统计学意义(χ2=17.47,P<0.01)。结论术前CT扫描确定股骨远端后髁角可以有效提高TKA手术股骨假体旋转力线,方法简单、有效、重复性良好。     

全膝关节置换术股骨假体旋转力线研究进展

股骨假体旋转力线是影响全膝关节置换术预后的极其重要环节.以哪条轴线作为术中参照轴才能够最大程度地保证股骨假体旋转轴线对位准确,目前仍存有争议.该文就全膝关节置换术中各种股骨假体旋转定位参照轴的可靠性等作一综述.     

残留内翻对弓形股骨患者全膝关节置换术后功能恢复的影响

目的探究残留内翻的下肢力线对弓形股骨患者行全膝关节置换术(total knee arthroplasty,TKA)术后功能恢复的影响。方法本研究回顾性收集西安市红会医院膝关节外科2015年1月至2015年12月,接受同一术者实施TKA的59例(71膝)骨关节炎患者的全部资料,其中男6例(8膝),女53例(63膝);年龄58~82岁,平均(67.7±5.7)岁。测量患者股骨侧弓角(femoral bowing angle,FBA)及下肢力线(hip-knee-ankle angle,HKA)。FBA<177°定义为弓形股骨。根据术后负重位标准正位X线片将患者分为两组:残留内翻组32例37膝(HKA<177°),中立位力线组27例34膝[HKA为(180±3)°]。以美国膝关节协会评分(knee society score,KSS)及西安大略和麦克马斯特大学骨关节炎指数评分(the western Ontario and McMaster universities osteoarthritis index,WOMAC)评价两组术后功能及症状。结果患者均获随访,随访时间43~55个月,平均随访时间为(49.30±4.11)个月。全部患者均未见假体松动、感染等严重并发症。两组患者术前KSS及WOMAC评分比较,差异无统计学意义(P<0.05);手术前后比较差异有统计学意义(P>0.05);术后残留内翻组WOMAC总分[(5.57±6.23)分]较中立位力线组[(9.27±8.86)分]明显降低,WOMAC C部分(日常生活困难程度)评分[(4.95±5.87)分]显著低于中立位力线组[(8.24±7.68)分],余各评分比较差异无统计学意义(P<0.05)。结论相比中立位力线,存在弓形股骨的患者行TKA术后下肢力线残留内翻可以获得更好的临床结局,但中远期疗效有待进一步观察。     

全膝关节置换术后股骨远端骨折的治疗进展

人工全膝关节置换术（totalkneearthroplasty,TKA）后股骨远端骨折在临床上很少见，发病率为0.3%~2.5%[1-3]。一旦发生，处理却十分棘手。随着TKA手术数量的逐步增加，这类骨折的发生亦将增多。一、病因TKA后发生股骨髁上骨折在病理学上有很多因素,包括股骨部件前翼应力遮挡、术后血供差所致的骨塑形不完全、股骨部件覆盖股骨远端部分与股骨皮质弹性模量存在相对差别[4,5]、骨水泥或金属磨损碎屑所导致的股骨远侧部分骨溶解[6]。股骨前方骨皮质切除过多形成切迹或凹槽增加骨折的发生率，40%~52%股骨髁上骨折与股骨前部凹槽有关[3]。常见…     

确定股骨远端旋转力线在膝关节置换中的意义

目的应用MRI测量探讨股骨远端各旋转轴线的关系,为人工全膝关节置换术(TKA)股骨远端旋转力线提供参考。方法选取苏浙地区健康汉族成人106例,膝关节共197个。对所选膝关节行MRI平扫,在MRI横断面图像上进行定位参照轴线,包括外科经股骨上髁轴线(STEA)、临床经股骨上髁轴线(CTEA)、前后轴线(APL)及股骨后髁轴线(PCL)。对轴线参数股骨后髁角(PCA)、髁扭转角(CTA)及前后轴线的垂线与后髁轴线的夹角(PAPA)进行测量。比较各角度不同性别、不同侧别均数的差异是否具有统计学意义。结果PCA平均为3.56°±0.26°,CTA平均为6.35°±0.72°,PAPA平均为4.08°±0.22°。不同性别、侧别的PCA均数差异无统计学意义(P0.05),不同性别、侧别的CTA、PAPA均数差异有统计学意义(P0.05)。结论应用MRI测量确定股骨远端轴线参数是一种可靠的方法,不同性别、侧别PCA相对恒定,STEA可作为TKA中股骨远端假体旋转参照力线。     

两种股骨截骨角度对膝关节置换术中股骨假体冠状位对线的影响

[目的]研究两种股骨远端外翻截骨角测定方法在膝关节置换术中对股骨假体对线的影响。[方法]对本院2015年3月~2015年6月由两名主刀医师完成的连续111例共137膝全膝关节置换术进行回顾性研究。两名主刀医师术前计划时在下肢全长X线片上测量股骨远端外翻截骨角度的方法不同,并以此分为两组。第一组利用股骨远端1/3解剖轴与股骨力线轴夹角(DFMA)作为股骨远端外翻截骨角,共71膝;第二组利用股骨解剖轴与股骨力线轴夹角(FMA)进行外翻截骨,共66膝。术后测量标准下肢全长X线片中股骨力线轴与股骨假体远端内外侧髁连线之夹角并比较两组结果的差异。[结果]两组患者的年龄、BMI、术前内翻角度、术前HSS评分、术后HSS评分差异均无统计学意义(P=0.149~0.985)。DFMA组术中所使用的股骨外翻截骨角度实际为6.08°±1.57°,FMA组为4.82°±0.74°,两组截骨角度差异有统计学意义(P<0.05)。DFMA组76.1%的术后股骨假体在0°±2°范围内,显著优于FMA组的51.50%,(P=0.005),并且DFMA组74.60%的术后下肢力线在0°±3°范围内,显著优于FMA组的53.00%,(P=0.008)。DFMA组术后下肢力线角度与FMA组差异无统计学意义(1.60°±2.46°vs 1.98°±3.35°,P=0.458)。[结论]内翻膝使用股骨远端1/3解剖轴与力线轴夹角作为个性化股骨外翻截骨角度,术后股骨假体冠状面位置优于使用股骨解剖轴与力线轴夹角。应用股骨解剖轴线确定股骨外翻截骨角度往往偏小,导致残留膝关节内翻畸形。     

Osteolysis of the distal femur after total knee arthroplasty

An 11.1% incidence of femoral osteolysis (30 cases in 28 patients) was identified in a series of 271 primary total knee arthroplasties. Two minimally constrained total knee designs (Synatomic [Depuy, Warsaw, IN] and Porous-Coated Anatomic [PCA, Howmedica, Rutherford, NJ]) were used in this patient population. Femoral osteolysis was observed in 26 Synatomic and 4 PCA knees. The average follow-up period was 52 months (range, 24–96 months). Osteolytic lesions were identified radiographically, adjacent to the nonporous-coated (smooth) regions of the anterior and posterior flanges of the Synatomic and PCA femoral components. The average time to the diagnosis of femoral osteolysis was 31 months (range, 7–96 months). The average patient age at the time of primary total knee arthroplasty was 63 years (range, 43–83 years) and the average weight was 180 lb. (range, 107–278 lb.). Sixteen of the 30 cases were in men. All of the cases with femoral osteolysis had cementless implantation. Tissue specimens were obtained from the 18 cases requiring revision. Implants remained in situ an average of 66 months (range, 15–96 months) prior to revision. In 16 of the 18 cases revised, the femoral component was clinically and radiographically stable. Six of 18 cases were revised for severe osteolysis. The remaining 12 cases were revised for failed metal-backed patellae, failed cementless tibial fixation, or advanced polyethylene wear. Wear of the thin tibial inserts and patellar components were the two sources of particulate polyethylene. Polyethylene debris was observed in all tissue specimens. In cases with failed metal-backed patellae or impingement of the tibial locking pin-and-clip, fine metallic debris was also noted in tissue specimens. Microscopic evaluation of the osteolytic tissue revealed a florid histiocytic response with occasional giant cells. Intracellular submicron particulate polyethylene was identified with polarized light microscopy and oil-red-O staining techniques. In the study population, statistically significant factors associated with femoral osteolysis included male gender (P < .05), younger age (P < .05), increased patient weight (P < .05), positive tibial osteolysis (P < .001), osteoarthritis (P < .07), and length of time in situ (P < .001). In addition, patients with a Synatomic prosthesis were at increased risk for osteolysis compared to patients with a PCA device (P < .02). The authors postulate that histiocytic granuloma gained access to the proximal femur primarily via the unbonded interface between the smooth metal and bone.     

Bony landmarks and rotational alignment in total knee arthroplasty for Chinese osteoarthritic knees with varus or valgus deformities

The purpose of this study was to investigate the rotational mismatch of total knee arthroplasty when taking the medial one third of the tibial tuberosity as a rotational landmark in Chinese osteoarthritic knees. Computed tomographic images of 49 osteoarthritic knees (42 with varus and 7 with valgus deformities) and 10 healthy knees were analyzed. The angle (alpha) between the 2 baselines for the anteroposterior axis of the femoral and tibial components was measured. The mean value of alpha in healthy knees was +6.45 degrees, which increased significantly to +11.53 degrees in varus knees (P = .002) and +12.17 degrees in valgus knees (P = .04). It showed that there is a tendency for the tibial component to be externally rotated when the medial one third of the tibial tuberosity is defined as a rotational landmark. This finding is particularly prominent in Chinese osteoarthritic knees with varus or valgus deformities.     

Changes in bone mineral density of the distal femur after revision total knee arthroplasty with metaphyseal press-fit stem

Background  

The effect of postoperative adaptive bone remodeling following a stemmed femoral implant in revision total knee arthroplasty (rTKA) is unknown. The aim of this study was to evaluate bone mineral density (BMD) changes of the distal femur following cemented rTKA with a 100-mm press-fit stem.     

Cutting error of the distal femur in total knee arthroplasty by use of a navigation system

The aim of this study was to evaluate the alignment of the distal femoral cutting surface using a navigation system to determine the accuracy of bone cutting. We evaluated 20 knees in 20 patients. After cutting the distal femur, the cutting surface was validated using the navigated cutting block adapter, and the angular difference between the cutting surface and that preoperatively planned in the sagittal and coronal planes was recorded. The average error of all knees was 1.6° ± 2.2° in extension, and 14 (70%) of 20 knees were cut in an extended position. Our tendency is to cut the distal femur in an extended position with the first femoral cut in the sagittal plane.     

Assessment of relative rotational alignment in total knee arthroplasty: usefulness of the modified Eckhoff method

In 1995, Eckhoff and colleagues demonstrated a new method for assessing relative rotational alignment of the femoral and tibial components in total knee arthroplasty (TKA). We studied the usefulness of a modified Eckhoff method. Five knee prostheses (Natural Knee, Deltafit, and three different sizes of Press-Fit Condylar) were used in an in-vitro study. A series of lateral radiographs were taken with the femoral component rotated in 1° increments from 15° internal rotation to 15° external rotation. The rotation of the implant was calculated based on the geometric relationship of pegs that were present symmetrically on the medial and lateral sides of the femoral components in all prostheses. In a study of the clinical applications, two independent observers measured the relative rotation of 18 knees in 16 patients after TKA, using this method. In the in-vitro study, the measurement error of rotation averaged 0.27°, and the maximum error was 0.96°. Clinically, the mean difference between the measurements of the two observers in each knee was 0.64°; there was a high correlation between the values measured by the two observers (r = 0.89; P < 0.0001). This is a useful method for determining the relative rotation in TKA accurately and reproducibly. Received for publication on June 30, 1999; accepted on Aug. 24, 1999     

Is bone density in the distal femur affected by use of cement and by femoral component design in total knee arthroplasty?

The objective of this study was to evaluate changes in bone density in the distal femur 2 years after total knee arthroplasty with four different implant designs using cemented or cementless femoral components. Bone density was measured retrospectively from radiographs of 114 knees, using a densitometer. A decrease in bone density of up to 57% was identified in the distal femora with a cemented femoral component 2 years after surgery, compared with a decrease of up to 28% with a cementless, porous-coated component of the same design. The differences between the four implant designs in the changes in bone density in the anterior distal femur were significant at 2 years (P < 0.001). A possible cause of this result may be a difference in load transfer due to the different methods of fixation. The surgeon should expect decreased bone density in the distal femur at the time of revision surgery, especially with a cemented femoral component. Received for publication on June 5, 1998; accepted on Dec. 11, 1998     

An additional reference axis for determining rotational alignment of the femoral component in total knee arthroplasty

No studies have examined the trochlear line connecting the most anterior projections of the lateral and medial femoral condyles in relation to the surgical epicondylar axis. To determine if the trochlear line is more consistent relative to the transepicondylar axis than the posterior condylar axis and the Whiteside's line, the angles between the surgical epicondylar axis and each of the 3 axes in 50 knees of cadavers were measured using computed tomography scans. The results showed that the variability in the trochlear line for referencing the transepicondylar axis was comparable to those of the Whiteside line and the posterior condylar axis. The trochlear line may be considered as an additional reference axis for determining the rotational alignment of the femoral component in total knee arthroplasty.     

Restoration of the joint line in total knee arthroplasty

The purpose of the study was to assess the effect of the joint line position in a posterior cruciate ligament–retaining, mobile-bearing total knee arthroplasty (TKA). Seventy-six consecutive TKAs performed by 1 surgeon were prospectively assessed for a minimum of 2.5 years. Posterior cruciate ligament–retaining, mobile-bearing TKA was performed in all cases. The joint line was elevated 1 mm on average (range, −11 to +10). There was no correlation between joint line position and range of motion, knee function scores, knee pain scores, or patellar height. The joint line position in a posterior cruciate–retaining, mobile-bearing (LCS AP Glide; DePuy, Leeds, United Kingdom) TKA did not affect the early clinical results.