动态MRI的一些参数测量在定量评价髌股关节中的价值

目的:通过测量髌股关节动态MRI的一些参数,比较不同屈曲角度下正常人及患者之间的差异性。方法:对两组(正常组30个,病例组20个)膝关节分别在被动屈曲0°,6°,12°,18°,24°,30°,36°下进行轴位动态MRI检查,测量髌骨最大径(MPW),外侧髌股角(LPA),股骨滑车沟角(FTA),髌骨倾斜角(PTA),股骨滑车沟深度(FTD),分别比较正常组及病例组在七个不同屈曲角度下各测量参数的差异性。结果:各参数在正常组及病例组在不同的屈曲角度下组内均无显著性差异;PTA及FTD在所有角度下均有组间的显著性差异,FTA在部分角度下有显著性差异。结论:动态MRI下的PTA及FTD可以很好的定量评价髌股关节的对合关系,FTD在18°及24°下也可以用来定量评价髌股关节的对合关系,建议在膝关节屈曲20°左右进行MR检查测量PTA、FTD、FTA来定量评价髌股关节。     

髌骨位姿异常对髌股关节接触影响的研究

目的 深入研究髌骨位姿异常对髌股关节的接触影响.方法 通过正常膝关节MRI图像数据建立了髌股关节的正常和异常接触模型,基于正交试验对不同水平的髌股关节异常接触模型进行了有限元仿真模拟.结果 1)在膝关节屈曲过程中,髌股关节接触特性(Von Mises应力、接触压力和接触面积)对髌骨的屈曲和旋转参数最为敏感;2)髌股异常...     

髌股关节退行性病变的X线摄影新方法

髌股关节是伸膝装置中的重要组成部分,髌骨在股骨滑车凹中正常运动轨迹依赖于髌骨与股骨髁间凹的骨性关节和其周围的韧带.髌股关节运动轨迹发生改变,导致软骨软化甚至演变为髌股关节骨性关节炎.笔者采用站立位膝关节屈曲多角度侧位X线摄影,显示髌骨位置、髌股关节间隙及其他膝关节病变,为骨科医师提供准确的诊断及治疗依据.     

髌股关节退行性病变的摄影方法学研究

目的 探讨髌股关节多角度侧位投照方法的临床价值.方法 收集50例膝关节疼痛的患者,分别采取180°、135°、90°膝关节屈伸角度侧位等多角度髌股关节X线摄影,比较髌股关节退行性病变的X线表现.结果 多角度髌股关节侧位投照显示,髌骨后缘关节面增生毛糙50例,股骨滑车面增生硬化及髌股关节间隙变窄43例,胫股关节间隙变窄23例,髌骨同定6例,而常规位置阳性显示率较低.2种投照摄影方法比较,股骨滑车、髌骨后缘、髌股关节间隙及髌骨活动范围等部位显示率差异有统计学意义(P＜0.05).多角度投照方法对观察股骨滑车面、髌骨关节面、髌骨移动范围、髌股和胫股关节间隙以及确定髌骨高位等退变特征有明显优势.结论 多角度髌股关节侧位投照是一种相对客观的显示髌骨位置及髌股关节间隙的X线摄影方法,可在临床检查中广泛使用.     

髌骨位置的CT几何测量——对髌骨移位角的初步研究

目的:为在横断面上评价膑骨位置,本文提出膑骨移位角(PSA)作为CT上髌骨位置的测量指标.材料和方法:对42例80个正常膝关节和11例18个膑骨半脱位膝关节CT的不同层面上的膑骨倾斜角(PTA)、髌骨外移距离(LPD)、髌骨二分比例(BSO)和PSA进行测量.对比这些参数的测量重复性,探讨PSA的价值.结果:正常组:PSA各平面平均相差0.4°,脱位组:PSA各平面平均相差1.2°.PSA各平面平均值相差不显著(P>0.05).而膝关节CT的不同平面上的PTA,LPD和BSO平均测量值有较大差异,各平面测量值之间相差显著(P<0.05).说明PSA较其它测量参数有更好的测量重复性.正常组PSA(平均7.6°)与脱位组PSA(平均13.6°)比较前者小(P<0.05).结论:作者认为PSA在膝关节不同平面之间有较好的重复性,作为横断面上估价髌骨位置的指标是有意义的.     

MRI对复发性髌骨不稳的解剖学危险因素的测量与评估

目的 定量测量并评估复发性髌骨不稳患者的髌股解剖学相关指标及其首要危险预测因素.方法 对52例经保守治疗失败的复发性髌骨不稳的年轻患者患膝进行回顾性MRI图像分析,测量指标包括描述髌骨轨迹的3个参数:髌骨偏移指数(BSO)、滑车适合角(CA)和髌骨倾斜角(PTA)以及描述髌股关节解剖学的7个参数:滑车沟角度(SA)、股骨外侧滑车倾斜角(LTI)、股骨滑车面对称性、股骨滑车深度、ISR(Insall-Salvati Ratio)、C-D(Caton-Deschamps index)和胫骨结节-股骨滑车沟(TT-TG)距离,并对测量结果进行Pearson's相关及多元逐步回归分析.结果 髌骨轨迹异常与LTI、TT-TG距离和ISR均存在显著相关性,而与股骨滑车深度、SA、滑车面对称性及C-D之间无统计学相关性或仅有部分指标相关.解剖学参数LTI、TT-TG距离及ISR构成的回归模型对BSO、CA和PTA的拟合优度R2分别为0.58、0.47和0.43(P<0.001),其中LTI的标准化回归系数β值最大,其次为TT-TG距离和ISR.结论 伸膝位时,MRI定量测量的髌股解剖学相关参数可以一定程度上解释复发性髌骨轨迹的外移和倾斜,其中:LTI是导致髌骨轨迹异常的解剖学相关指标中的首要危险预测因素,其次分别是TT-TG距离及ISR.     

CT在评估髌股关节排列中的应用

目的介绍和分析利用ＣＴ评估髌股关节排列的方法和价值。方法在屈膝３０°时用ＣＴ检测３２例５０侧膝髌股关节疼痛者（轴位Ｘ线片上髌股排列基本正常）和１５例２０侧膝无症状者的髌股关节,测量其髁间沟角、和谐角及外侧髌股角,观察病变在ＣＴ上的表现,分析髌股关节疼痛患者的髌股排列状况。结果髌股关节疼痛患者较无症状者具有较明显的髌股排列紊乱,单纯髌骨外置者１１侧膝,单纯髌骨倾斜者８侧膝,髌骨外置合并髌骨倾斜者１０侧膝。结论利用ＣＴ评估髌股关节排列较普通Ｘ线片有显著的优越性,可指导治疗的术式选择     

胫骨结节抬高内移术的生物力学研究

目的:探讨胫骨结节抬高内移术后膝关节在不同屈曲角度下髌股关节面接触面积和接触压力的变化.方法:选用8具新鲜离体膝关节标本,测量胫骨结节抬高术和胫骨结节抬高内移术前后膝关节Q角角度,并分别采用压敏片和染色法测试两种手术前后髌股关节接触面积、接触部位和应力分布的变化.结果:胫骨结节抬高内移(1.0cm)术后,Q角变小,接触面积减小,接触部位上移,腱股接触提早出现(54.6°),小屈膝角度(30°～60°)时接触压力明显减小,各屈膝角度下外侧关节面的接触压力均向内侧转移.以上变化与胫骨结节抬高术后的变化有明显差异.胫骨结节抬高内移0.5cm时,髌骨接触面积、部位、接触压力变化较小,无明显治疗意义.抬高内移达1.5cm时可造成髌骨内倾斜、髌骨不稳等严重的解剖关系紊乱.结论:胫骨结节抬高内移各1.0cm是较适宜的范围,可矫正髌骨外倾斜,改变髌股习惯接触部位,减轻髌股(尤其外侧关节面)接触压力,重新分布接触压力,腱股接触(55°左右)提早出现.以上变化可矫正髌股关节的解剖紊乱,对临床治疗髌骨软化症有一定意义.     

髌腱腱病患者髌股关节排列的磁共振成像

目的:利用磁共振成像技术探讨髌腱腱病患者中髌股关节的排列状态。材料和方法:36名运动员60膝参加本研究,其中髌腱腱病组21例共30膝,正常对照组15例共30膝。受试者以双侧(无症状成人)或患侧(髌腱腱病患者)膝接受MRI检查,在屈膝0°位非负重及负重15%体重状态下分别进行扫描。选取髌骨中部切面图像,测量滑车沟角、髌股适合角髌骨倾斜角以及髌骨外侧偏移量。结果:两组均在负重后髌股适合角减小、髌骨倾斜角减小、髌骨外侧偏移量增大(P<0.05)。髌腱腱病组在非负重状态下各指标与正常对照组相似(P>0.05),负重后髌骨外侧偏移量较正常对照组小(P<0.05),髌骨外侧偏移量负重前后之差也较正常对照组小(P<0.05)。结论:髌腱腱病患者存在髌股排列异常,负重后髌骨外侧偏移量低于正常。     

髌股关节切线位新摄影术的研究

目的探讨对髌股关节切线位摄影的新技术。方法在62例病人膝关节侧位平片上测量了膝关节屈曲角,髌骨后缘线与股骨长轴、胫骨长轴及胫骨前皮肤线之间的夹角。分析其间的相互关系,得出髌骨后缘线和股骨之间夹角与膝关节屈曲角成直线相关关系,其直线方程为     

Femorotibial rotation and the Q-angle related to the dislocating patella

PURPOSE: To compare the femorotibial rotation, the patellar translation, the hip-knee-ankle angle and the Q-angle in patients with a dislocation of the patella with those of healthy volunteers. Further, the clinically measured Q-angle was compared to that measured by radiography. MATERIAL AND METHODS: A system for measurement of patellar variables was previously developed and applied to 80 healthy volunteers. In the present study, 28 patients (20 women, 8 men) with dislocation of the patella were examined bilaterally. Fourteen patients had habitual dislocations (20 affected knees) and 14 patients traumatic dislocations (17 affected knees). In 20 patients the clinical Q-angle was measured bilaterally by an orthopaedic surgeon and in 9 of these patients also by a second independent orthopaedic surgeon. RESULTS: The most striking finding was that dislocating knees in both groups showed a smaller Q-angle than the healthy knees. Further, the habitual group showed greater relative rotation between the tibia and the femur and an increased patellar translation compared to the traumatic group and to the healthy volunteers. There was a poor correlation between clinical and radiographic measurements of the Q-angle and no correlation was found between two independent clinical measurements. CONCLUSION: Surgical operations aiming at decreasing the Q-angle should be challenged.     

Arthroscopic fixation of osteochondritis dissecans of the knee: clinical, magnetic resonance imaging, and arthroscopic follow-up

BACKGROUND: Optimal treatment of osteochondritis dissecans of the knee is still controversial. PURPOSE: To review a group of patients with osteochondritis dissecans of the knee who were treated with arthroscopic compressive screw fixation and who were evaluated with magnetic resonance imaging studies and a second-look arthroscopic procedure at follow-up. STUDY DESIGN: Case series; level of evidence, 4. METHODS: A total of 14 patients (15 knees) with osteochondritis dissecans of the knee were treated with arthroscopic titanium Herbert screw fixation of the osteochondral fragment. A second-look arthroscopic procedure was performed to remove hardware and to evaluate fragment stability. At final follow-up, magnetic resonance imaging studies were used to evaluate potential healing of the subchondral bone. Outcomes were clinically evaluated at a mean follow-up of 50 months (range, 25-104 months) by the Lysholm score and by the International Knee Documentation Committee score. RESULTS: At second-look arthroscopy, 14 of 15 knees showed evidence of a stable fragment with an intact smooth surface. According to magnetic resonance imaging parameters, 14 knees showed evidence of a healing process of the osteochondral fragment. The average Lysholm score improved 18 points from a mean of 79 preoperatively to 97 postoperatively, and according to the International Knee Documentation Committee score, 13 of 15 knees showed a normal result. CONCLUSION: This study suggests that magnetic resonance imaging parameters of a healed osteochondral fragment and patients with satisfactory functional results correspond with arthroscopic evidence of fragment stability. According to this study, arthroscopic fixation with compressive screws is an effective method of repair for osteochondritis dissecans of the knee.     

Prevalence of knee abnormalities in patients with osteoarthritis and anterior cruciate ligament injury identified with peripheral magnetic resonance imaging: a pilot study.

OBJECTIVES: 1) To assess, with a peripheral magnetic resonance imaging system (pMRI), the prevalence of bony and soft tissue abnormalities in the knee joints of normal subjects, osteoarthritis (OA) patients, and individuals who have suffered an anterior cruciate ligament (ACL) rupture; and 2) to compare the prevalence among groups. METHODS: Magnetic resonance (MR) images of 28 healthy, 32 OA, and 26 ACL damaged knees were acquired with a 1.0-T pMRI system. Two radiologists graded the presence and severity of 9 MR image features: cartilage degeneration, osteophytes, subchondral cyst, bone marrow edema, meniscal abnormality, ligament integrity, loose bodies, popliteal cysts, and joint effusion. RESULTS: Ten of 28 healthy (35.7%), 24 of 26 ACL (92.3%), and all OA knees (100%) showed prevalent cartilage defects; 5 healthy (17.9%), 20 ACL (76.9%), and all OA knees (100%) had osteophytes; and 9 normal (32.1%), 21 ACL (80.8%), and 29 OA knees (90.6%) had meniscal abnormalities. One-half of the knees in the OA group (16 of 32, 50%) had subchondral cysts, and almost one-half had bone marrow edema (15 of 32, 46.9%). These features were not common in the ACL group (7.7%, and 11.5%, respectively) and were not observed in healthy knees. The OA group had the most severe cartilage defects, osteophytes, bone marrow edema, subchondral cysts, and meniscal abnormalities; the ACL group showed more severe cartilage defects, osteophytes, and meniscal abnormalities than did normal subjects. CONCLUSION: The results suggest that knees that have sustained ACL damage have OA-like reatures; most subjects (19 of 26, 73.1%) could be identified as in the early stage of OA. The prominent abnormalities present in ACL-damaged knees are cartilage defects, osteophytes, and meniscal abnormalities.     

Jumper's knee and ultrasonography

Twenty-five patients, aged between 15 and 45 years old, who were athletically active, presented with jumper's knee (patellar tendinitis). By use of ultrasonographic examination, new and precise information was obtained that benefited the diagnosis, choice of treatment, and monitoring of the evolution of jumper's knee in our patients. In 18 of the 25 patients, only 1 knee was affected; in 7 of the patients, both knees were affected, thus making a total of 32 painful tendons. These 25 patients were compared with a control group of 15 healthy, athletically active subjects between the ages of 25 and 35 years old. In all of the 32 painful tendons, ultrasonographic anomalies were observed: thickening or swelling of the tendon (15 knees) appeared in acute cases; a heterogeneous structure of the tendon (24 knees); and thickening and irregularities of the tendinous envelope (8 knees). The 15 acute patients all responded to classic conservative treatment including physical therapy and electrotherapy. Four of the remaining 10 patients were treated successfully with various conservative treatments, including deep transverse friction massage with ice. The other six patients were treated surgically, with tenolysis and "carding" of the patellar tendon. In one patient, this procedure failed, and 12 months later a second operation was performed, in which the distal pole of the patella was resected and the patellar tendon reinserted into bone. Recovery was uneventful. Now, at least 2 years after treatment, all of the patients consider themselves healed.     

Second-look arthroscopic findings of 208 patients after ACL reconstruction

The aim of this study is to report the arthroscopic subjective findings of reconstructed anterior cruciate ligament (ACL) with good clinical outcome. Graft used for reconstruction was either patella bone-tendon-bone (PBTB) autograft or hamstring tendon [quadrupled semitendinous and gracilis tendon (QSGT)] autograft. From March 1997 to September 2003, among 716 ACL reconstructions 209 knees (208 patients) were available for second-look arthroscopy at a mean 21.2-month (range, 14–70 months) postoperative period. The second-look arthroscopy focused on the evaluation of (1) continuity of the reconstructed ACL graft, (2) subjective graft tension using a probe, (3) the extent of synovial coverage, (4) the prevalence of cyclops or cyclops-like lesion, and (5) bony change after notchplasty. Patellar tendon autograft was used in 80 knees, hamstring tendon autograft in 129 knees. Just prior to second-look arthroscopy two objective clinical evaluations, KT-2000 arthrometer and Lysholm knee score, were performed to verify good clinical outcomes. A comparison between the hamstring tendon group and the patella tendon group, hamstring group showed slightly better results in Lysholm knee scores and KT-2000 arthrometer but there were no statistically significant differences (p>0.05). Undetected partial graft tear was seen in 21 knees (10%). With regard to graft tension, a total of 181 grafts (87%) showed normal tension and 28 (13%) showed slight lax tension. The overall synovial coverage was poor in nine (4%) knees. The synovial coverage was slightly better in the hamstring tendon group. A total of 45 knees (21.5%) showed cyclops-like lesion in variable sizes and locations. Reformation of the notch was seen in 85 knees (40%). In conclusion, the findings of second-look arthroscopy of reconstructed ACL in good clinical outcome patients showed approximately 10% partial graft tear, 5% poor synovial coverage, 20% cyclops-like lesion, and 40% some notch reformation.     

Ultrasonography of jumper's knee

The aim of the study was to evaluate the role of ultrasonography (US) in the management of jumper's knees. Sixty-two cases of clinically suggested jumper's knees, 52 asymptomatic contralateral knees and 100 asymptomatic knees of healthy middle aged men were examined. In the symptomatic group US was normal in 25 cases, all recovered with conservative therapy. In 31 symptomatic knees the findings were consistent with jumper's knee as a hypoechoic lesion located in the upper insertion of the patellar tendon in 23 cases and in the distal insertion in one case. In 7 cases the lesion was situated in the insertion of the quadriceps tendon. Surgery was performed on 20 knees and in all of them there was a lesion matching the lesion detected by US. In 6 cases US findings were pathologic, but different from jumper's knee. US findings consistent with jumper's knee could not be detected in the asymptomatic group.     

The effect of a meniscal prosthesis on knee biomechanics and cartilage. An experimental study in rabbits.

A meniscal prosthesis made of Dacron with polyurethane coating was tested as a substitute for the medial meniscus in a rabbit experimental model concentrating on biomechanical behavior of the knee joint and gross and histologic evaluation 3 months after surgery. The results were compared to sham-operated knees, knees with a peripheral incision of the medial meniscus, and knees with a total meniscectomy. Knees with prosthesis implantation had the same stiffness as knees with sham-operation or meniscal incision, but knees with meniscectomy were stiffer (P less than 0.05). Knees with prosthesis showed lower energy storage during relaxation than knees with sham-operation or meniscal incision (P less than 0.05). Energy storage in the prosthesis group was similar to the meniscectomy group. Partial or total ingrowth of synovial tissue into the prosthesis was present in 93%, and 63% of the incised menisci had healed. Cartilage changes were present in 70% of the prosthesis group, in 25% of the knees with meniscal incision, and in all knees with meniscectomy. The sham-operated knees were free from cartilage degeneration. Knees with prosthesis had the same frequency of cartilage changes on the femur, but had less changes on the tibia compared to knees with meniscectomy. A high rate of osteophyte formation was observed after prosthesis implantation as well as following meniscectomy, but the osteophytes were larger in the prosthesis group (P less than 0.01). The most frequent and severe effect on the synovium was found in the prosthesis group (92%), but no foreign body reaction or loose Dacron particles were found.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hamstring/quadriceps strength ratios in knees with medial collateral ligament insufficiency. Isokinetic and isometric results and their relation to patients' long-term recovery

The purpose of this study was to investigate the peak torque and total work hamstring/quadriceps strength ratios (HQ-ratios) of 25 knees with medial collateral ligament (MCL) insufficiency and to find out the possible relation between different HQ-ratios and the long-term outcome of the patients. The isokinetic (speed 60 and 180 degrees/sec) and isometric muscle strengths were measured by a Cybex II dynamometer. Three standardized knee scoring scales were used to determine the subjective, clinical, and radiological outcome of the knees with MCL insufficiency. All tests showed great interpersonal variation in HQ-ratios even in the healthy knees (range from 23% to 183%). The average HQ-ratios between the uninjured and injured legs did not differ significantly from each other (range from 40% to 82%). The mean peak torques and total work of hamstrings as well as of quadriceps were slightly, but not significantly lower in the injured leg than on the uninjured side. The follow-up scores did not differ significantly between patient groups with low (less than or equal to 50%), optimal (50-80%), or high (greater than or equal to 80%) absolute HQ-ratios of the MCL insufficient knee. However, in every test the scores were significantly better for patients with an HQ-ratio difference of less than or equal to 15% between the injured and the uninjured side than for those with a clear difference (greater than 15%). The findings suggest that the HQ-ratio is a patient-specific parameter and that any general recommendation on its optimal value is difficult to give.(ABSTRACT TRUNCATED AT 250 WORDS)     

The position of the tibia tubercle in 0°–90° flexion: comparing patients with patella dislocation to healthy volunteers

Purpose

The aim of this study was to measure the tibia tubercle trochlea groove distance (TT–TG) as a function of knee flexion. Our hypothesis was that there is a different pattern in healthy volunteers and patients with patella instability (PFI).

Methods

Thirty-six knees of 30 patients with at least one dislocation of the patella and 30 knees of 30 healthy volunteers as control group were analysed with magnetic resonance imaging by three different observers. The TT–TG was measured in steps of 15° between 0° and 90° of knee flexion. Furthermore, the alignment of the leg (MA), the femur torsion (FTor) and the tibia torsion (TTor) was calculated.

Results

The TT–TG was higher in patients compared to volunteers and in extension compared to flexion. This difference was statistically significant (p < 0.05). Most of the patients with a TT–TG above 20 mm in extension showed a high decrease in flexion to normal values. In some patients, this compensating mechanism fails. MA, FTor and TTor were not different in patients and control group (n.s.).

Conclusion

The TT–TG distance is dynamic and decreased significantly during flexion in knees with PFI and healthy volunteers. However, there were a small number of patients in the PFI group where this compensation mechanism did not work. Therefore, the decision to perform a tibia tubercle osteotomy should not be based on one single measurement in extension or 30° of knee flexion.

Level of evidence

II.     

The combination of tibial anterior translation and axial rotation into a single biomechanical factor improves the prediction of patient satisfaction over each factor alone in patients with ACL reconstructed knees

Purpose

The purpose of this study was to identify biomechanical factors, in both reconstructed and healthy knees, that correlate with patient satisfaction after ACL reconstruction.

Methods

Seventeen patients who had undergone unilateral ACL reconstruction were reviewed 9 years post-op. Patients completed subjective questionnaires and underwent manual knee laxity testing (Lachman-Trillat, KT-1000, and pivot shift) and automated laxity testing. During automated testing, both legs were rotated into external rotation and then internal rotation until peak rotational torque reached 5.65 Nm. Load-deformation curves were generated from torque and rotation data. Features of the curves were extracted for analysis. Total leg rotation and anterior laxity during KT-1000 testing were combined into a single factor (Joint Play Envelope or JPE). Patients were divided into groups based on patient satisfaction scores (Group 1: Higher Satisfaction, Group 2: Lower Satisfaction, Group 3: Unsatisfied). Load-deformation curve features and manual laxity testing results were compared between groups 1 and 2 to determine which biomechanical factors could distinguish between the groups. Diagnostic screening values were calculated for KT-1000 testing, the pivot shift test, total leg rotation and JPE.

Results

During manual testing, no significant differences in biomechanical factors were found when comparing reconstructed knees in group 1 and group 2. When comparing the reconstructed and healthy knees within group 2, the reconstructed knees had a significantly higher displacement during the KT-1000 manual maximum test (p?<?0.002). When considering the reconstructed knees alone, neither the result of the pivot shift test nor KT-1000 testing could distinguish between group 1 and group 2. During automated testing, there were no significant differences between the groups when comparing the reconstructed lower limbs. The healthy lower limbs in group 2 had more maximum external rotation (p?<?0.02) and decreased stiffness at maximum external rotation (p?<?0.02) when compared to the healthy lower limbs in group 1. Total leg rotation was unable to distinguish between group 1 and group 2. JPE could distinguish between group 1 and group 2 when considering the reconstructed limb alone (p?<?0.02). All four diagnostic screening values for JPE were equal or higher than in the other criteria. JPE also showed the most significant correlation with patient satisfaction.

Conclusions

Joint Play Envelope is an objective measure that demonstrated improved predictive value as compared to other tests when used as a measure of satisfaction in patients with ACL reconstructed knees.