急性髌骨一过性外侧脱位的MRI诊断

目的:探讨MRI在急性髌骨一过性外侧脱位(TLPD)中的诊断优势.方法:回顾性分析2018年1月至2020年10月50例TLPD患者的影像学资料,重点分析其MRI表现特征及与X线平片比较优势.结果:TLPD在MRI上以股骨外侧髁与髌骨内侧骨髓水肿及内侧髌股韧带不同程度损伤为特征,多伴髌骨半脱位及外倾(本组84％)、关节...     

髌骨一过性外侧脱位的MRI表现

目的：探讨髌骨一过性外侧脱位（TLPD）的MRI表现。方法：回顾性分析44例TLPD患者临床及影像学表现。结果：44例（100%）均出现髌骨内下侧份和股骨滑车外侧髁的对吻性骨髓水肿，26例（50%）合并髌骨（22例）或股骨（4例）的骨软骨损伤，34例（77%）伴发MRC撕裂，21例（48%）伴发VMO损伤；27例(61%)存在股骨滑车发育不良；24例（55%）合并髌骨半脱位，4例(9%)合并高位髌骨；关节积液出现率为（100%），3例出现关节积脂血症，1例有关节囊破裂。结论：髌骨内下侧份和股骨滑车外侧髁的对吻性骨髓水肿是TLPD的典型MRI表现，常伴发髌骨内下侧缘骨软骨的骨折和MRC的损伤，股骨滑车发育不良和髌骨位置异常是其最常见的诱因。     

低场强MRI在膝关节不常见损伤类型中的应用价值

目的探讨低场强MRI对膝关节外伤后各类不常见损伤表现及其诊断价值。方法回顾分析经临床证实2010年1月-2012年12月385例膝关节外伤患者的MRI资料。将构成比≤5%的损伤归为不常见型损伤,统计各类不常见损伤的构成比并分析其MRI表现。结果 385例膝关节损伤患者发现半月板撕裂155例,十字韧带损伤117例,内侧副韧带损伤127例,骨挫伤84例,骨折44例,多种损伤可复合存在。同时发现半月板后根部损伤15例(4.0%);半月板关节囊分离3例(0.8%);后外侧复合体损伤17例(4.4%);Segond骨折6例(1.6%);板股韧带损伤1例(0.5%);髌骨内侧支持带损伤19例(4.9%);软骨骨折16例(4.2%),其中髌骨软骨骨折5例(1.3%),股骨内、外髁软骨骨折11例(2.9%)。结论低场强MRI对膝关节不常见损伤的诊断具有很高的准确性,是膝关节外伤后理想的一种非创伤性检查方法。     

带线锚钉治疗急性创伤性髌骨脱位后髌骨内侧缘撕脱骨折伴内侧髌股韧带损伤的疗效分析

目的：探讨带线锚钉治疗急性创伤性髌骨脱位后髌骨内侧缘撕脱骨折伴内侧髌股韧带损伤的疗效。方法：自2003年9月至2008年7月共收治28例急性髌骨脱位后髌骨内侧缘撕脱骨折伴内侧髌股韧带损伤患者。对28例患者均采用开放手术下带线锚钉固定髌骨骨折及修复内侧髌股韧带损伤。术后1年进行术后的髌骨骨折Levack功能评分。结果：所有患者术后随访时间12～30个月,平均（16±3.50）个月。术后1年的髌骨骨折Levack功能评分标准优23例,可3例,差2例,优秀率达82.14%。无再次髌骨脱位或伴脱位患者。结论：开放手术下带线锚钉治疗对髌骨骨折固定及内侧髌股韧带修复可靠,是治疗急性创伤性髌骨脱位后髌骨内侧缘撕脱骨折伴内侧髌股韧带损伤的有效方法。     

关节镜下外侧支持带松解和内侧紧缩并髌韧带止点移位治疗复发性髌骨脱位

目的 探讨关节镜下外侧支持带松解和内侧关节囊紧缩并髌韧带止点移位治疗复发性髌骨脱位.方法 复发性髌骨脱位28侧.关节镜下探查,软骨修整、钻孔,游离体摘除,外侧支持带充分松解后,采用双固定螺钉加强并紧缩内侧关节囊,同时将髌韧带止点内侧移位并固定,关节镜下观察髌骨运动轨迹,观察股骨滑车与髌骨的对应关系.结果 所有患者术后均获随访,随访12～34个月,平均17个月.术后膝关节稳定性增加,无髌骨再脱位发生.恐惧试验阴性,髌骨倾斜试验对称,髌股关节研磨试验阴性26例,阳性2例.髌骨轴位X线片和MRI显示髌股关节解剖关系恢复正常26例,髌骨轻度半脱位2例.术前Lyshoh评分平均(73.8±4.5)分,术后(92.4±2.8)分.结论 关节镜下外侧支持带松解和内侧关节囊紧缩并髌韧带止点移位治疗复发性髌骨脱位,具有创伤小、恢复快、复发率低、效果可靠等优点,同时,双固定螺钉固定修复术操作简单,切口小,术后可最大限度恢复功能.对于维持髌骨的运动轨迹具有重要作用.     

高频超声在急性创伤性髌骨脱位所致软骨损伤中的应用研究

目的研究急性创伤性髌骨脱位所致软骨损伤的高频超声特征。方法回顾性分析25例经手术证实的急性创伤性髌骨脱位患者高频超声资料,总结其特征,并与手术、MRI结果对比。结果 25例急性创伤性髌骨脱位患者,共计53处软骨损伤,其中髌骨内下缘软骨损伤25处,股骨外髁外侧面软骨损伤23处,股骨内髁外侧面软骨损伤1处,股骨滑车软骨损伤4处,无胫骨平台软骨损伤;其中髌骨内下缘及股骨外侧髁外侧面同时软骨损伤23处。高频超声诊断关节软骨损伤的敏感性为75.5%,特异性为97.2%;MRI诊断关节软骨损伤的敏感性为90.6%,特异性为100%;两种方法诊断软骨损伤的敏感性、特异性比较差异无统计学意义。结论急性创伤性髌骨脱位常造成典型部位(髌骨内下缘及股骨外髁外侧面)软骨损伤,高频超声及MRI均能对其有效诊断。     

内侧髌股韧带重建治疗创伤性髌骨脱位25例

【目的】探讨游离肌腱移植重建内侧髌股韧带（MPFL）手术方法及治疗髌骨脱位的疗效。【方法】2008年5月至2012年7月收治创伤性髌骨脱位患者25例共25膝,均采用游离自体半腱肌腱,通过髌骨双隧道移植重建MPFL,关节镜下动态调整移植肌腱的张力,确保髌股关系对合正常,应用挤压螺钉固定肌腱游离端于股骨止点。手术前后均行 Lysholm评分。【结果】25例患者均获得随访,随访时间8～48个月,平均26个月。全部病例复查时均未再发生脱位,恐惧试验阴性,经MRI证实髌股对合关系正常。术后Lysholm评分末次随访为（87．3±6．5）分,较术前（61．2±8．6）分差异有统计学意义（t＝-23．6,P＜0．05）。4例在术后6个月内感膝关节屈曲时髌内侧有紧张感,末次随访时均消失;3例患者末次随访时诉膝前在上下楼梯时有酸痛感,此3例患者均为手术时髌骨软骨面有损伤。【结论】采用以游离肌腱重建 MPFL手术治疗创伤性髌骨脱位,临床效果满意。     

1.5TMRI在膝关节损伤中的诊断价值

目的:探讨膝关节损伤特征,通过分析膝关节损伤的1.5T MRI影像表现,为有效诊治运动所致膝关节损伤提供准确诊断依据。材料与方法:本次收集25例膝关节损伤病例,平均年龄30岁。全部病例均用1.5TMRI膝关检查,应用膝关节线圈,斜矢状位TSE T_1WI、TSE T_2WI、PD-SPIR和冠状位、轴位TSE T_2WI扫描。所有影像学特征均与临床及关节镜手术结果对照分析。结果:(1)半月板损伤:20例内侧半月板后角Ⅲ度损伤,20例外侧半月板前角Ⅲ度损伤,13例外侧半月板后角Ⅲ度损伤;(2)韧带损伤:13条前交叉韧带完全断裂,与关节镜诊断完全符合率为82.00%。6条前交叉韧带撕裂(部分断裂),与关节镜断完全符合率100%。1条前交叉韧带胫骨端撕脱,与关节镜诊断符合率为100%。17例内侧副韧带II度损伤,5例内侧副韧带Ⅲ度断裂损伤;8例外侧副韧带断裂,8例腘肌腱断裂;2例髌韧带断裂,8例髌腱炎。(3)软骨损伤:20例髌骨软骨Ⅲ度损伤,2例髌骨软骨IV度损伤。(4)骨质改变:8例骨折分别位于髌骨上极、胫骨平台塌陷骨折、胫骨前交叉韧带止点骨折,10例骨挫伤。(5)25例均表现为关节囊内的长T_1长T_2信号,其中1例患者为关节积血。结论:1.5T MRI能够最佳地显示膝关节多发运动损伤、急慢性损伤以及对损伤程度的判定,有助于指导运动过程中膝关节功能保护和损伤康复及治疗。     

关节镜辅助治疗髌骨骨软骨骨折

目的对髌骨骨软骨骨折临床治疗结果进行分析,并回顾以往文献报告,总结该病的治疗、预后及治疗体会。方法回顾性分析2005年9月～2010年9月该院收治的35例髌骨骨软骨骨折患者。均为闭合性骨折,并且为运动中髌骨一过性脱位受伤,所有病例均手术治疗,可吸收钉固定7例,PDS缝线固定3例,可吸收钉加PDS缝线固定24例,骨折块粉碎、压缩、无法固定而骨折块摘除1例,35例患者均行髌内侧支持带紧缩缝合术。随访骨折愈合及关节功能情况。结果 32例患者获得随访(可吸收钉固定5例,PDS缝线固定2例,可吸收钉及PDS缝线固定24例,骨折块摘除1例,3例失随访,随访时间6～41个月,平均25.9个月,31例内固定患者骨折均获得骨性愈合,关节活动度恢复正常范围,无明显疼痛症状及髌骨习惯性脱位现象。结论髌骨骨软骨骨折好发于青少年,应早期明确诊断、及时治疗,根据骨折块大小、位置及是否连同软骨下骨,行复位内固定术或骨块摘除,合并髌骨自发性脱位者应行髌内侧支持带紧缩术,以纠正髌骨轨迹,降低髌骨再脱位几率,降低创伤性关节炎的发生率。     

青少年急性髌骨脱位后骨软骨损伤的MRI分析

目的分析青少年急性髌骨脱位后骨软骨损伤的MRI特点。材料与方法对41例青少年急性髌骨脱位的MRI资料进行回顾性分析,所有患者均行常规MR矢状面、冠状面和横断面T1WI、T2WI、脂肪抑制FSE序列扫描,分析骨软骨损伤的特点。结果急性髌骨脱位后,41例青少年有37例(90.2%)出现骨软骨损伤,其中Ⅰ级、Ⅱ级、Ⅲ级、Ⅳ级骨软骨损伤的发生率分别为10.5%、12.2%、24.5%、52.6%。青少年髌骨侧、股骨侧、髌骨-股骨骨软骨损伤的发生率分别为32.4%、13.5%、54.0%。结论青少年骨软骨损伤以Ⅲ级、Ⅳ级多见,损伤部位以髌骨侧及多部位损伤常见。     

Irreducible lateral patellar dislocation: the importance of impaction fracture recognition

Irreducible lateral patellar dislocation may occur in the older patient with a previous history of patellofemoral arthritis. The only subtle finding on physical examination to suggest this diagnosis will be positioning of the knee in less flexion than a typical lateral patellar dislocation, anterolateral position of the patella and internal rotation of the patella from the coronal plane. That is, the patella is dislocated laterally but the lateral border comes to lie in a position of variable degrees of anterior displacement relative to the medial patellar border. Plain x-rays may reveal the rotation of the patella along the vertical axis and an anterolateral rather than lateral positioning of the patella. Computed tomographic scanning is of benefit if the diagnosis is suspected or if an initial attempt at closed reduction is unsuccessful. Open reduction is recommended, if a single closed reduction attempt is not successful, to prevent any potential worsening of the patellar impaction fracture. A laterally dislocated patella that displays internal rotation about the vertical axis or the "flipped patella" sign is pathognomonic of an irreducible patellar dislocation and suggests patellar impaction on a lateral femoral condylar ridge osteophyte. Open reduction is easily achieved through a vertically oriented quadriceps tenotomy without the need for medial repair.     

Die Patellaluxation im Kindes- und Jugendalter

Background

Lateral dislocation of the patella is a common injury in adolescents and young adults which is often associated with an imbalance of the active, passive and static stabilizers of the patellofemoral joint. Therefore, a detailed medical history and a thorough clinical and radiological examination are required to detect the relevant predisposing factors to lateral patellar instability. When indicated radiographic analysis of the lower leg geometry should be added to standard radiographs and magnetic resonance imaging (MRI) examination of the affected knee joint.

Methods

Recent randomized control trials of operatively treated primary lateral patellar dislocations failed to improve the redislocation rate or the subjective clinical outcome compared with conservative management. Thus, non-operative therapy has been recommended as the treatment of choice in primary dislocations. However, the indications for operative treatment after primary patellar dislocations include the presence of an osteochondral fragment, substantial disruption of the medial soft tissue stabilizers and a laterally subluxated patella with normal alignment of the contralateral knee. Although, there is no conclusive evidence that primary medial patellofemoral ligament (MPFL) repair in first time patellar dislocations reduces the incidence of recurrence, it seems reasonable to address MPFL injury at least in those cases where an osteochondral flake fracture requires an early operative procedure. Surgery may be required in patients where non-operative treatment has failed and instability episodes recur. In these patients preoperative planning requires a detailed analysis of the individual anatomy, including the identification and evaluation of predisposing factors that contribute to patellofemoral instability but has to respect the open growth plates in the young patient. Injury to the MPFL occurs in almost all patients after primary patellar dislocations even in adolescents and young adults. Therefore MPFL augmentation techniques without violating the distal medial femur epiphysis have gained in importance in recent years.

Conclusion

In view of the high rates of patellar redislocation particularly in young patients, patellofemoral instability necessitates a better understanding of the factors that lead to recurrent dislocations. Therefore, prospective-randomized controlled trials are required to establish evidence-based recommendations how to treat first time instability. In addition more comprehensive data is needed to differentiate between those patients who have a high likelihood of recurrent episodes of patellar instability and those for whom conservative treatment might be successful.     

MR imaging of patellar dislocation and relocation

Patellar dislocation and relocation (PDR) typically occurs suddenly after trauma or torsional stress on the extensor mechanism. Clinical evaluation after patellar dislocation/relocation usually reveals a swollen knee that is difficult to examine. Radiographs may show hemathroses and a minority of patients will have a chip fracture of the patella. Magnetic resonance (MR) imaging features seen with PDR include disruption or sprain of the medial retinaculum, lateral patellar tilt or subluxation, lateral femoral condylar and medical patellar osseous contusions, osteochondral injury, damage to Hoffa's fat pad, and joint effusion. Up to one third of patients will also show concomitant injury to the major ligaments of the knee or menisci. Without repair of the primary injury, redislocation occurs in greater than one half of patients. Consequently, surgical correction is often advocated. This article reviews the factors predisposing to PDR, the activities associated with PDR, the clinical, radiographic, and MR imaging features of PDR, and (briefly) therapy for this injury.     

Patellafraktur nach MPFL-Plastik bei erhöhtem TTTG-Abstand

A 19-year-old patient suffered recurrent patellar dislocations and was treated by medial patellofemoral ligament (MPFL) reconstruction with a gracilis ligament autograft. Normal knee flexion while bowling led to a patella fracture 4 years after surgery. Further diagnostics showed a normal mechanical axis, no torsional deformity, no patellar or trochlear dysplasia and normal patella height. Source of the patellar instability was an increased tibial tuberosity-trochlea groove distance (19 mm). Surgical treatment was carried out with screw fixation of the patella fracture and tibial tuberosity transfer. The source of the patellar instability was not completely analyzed before surgery and ultimately led to a patellar fracture. A complete diagnostics of a patellar dislocation is always necessary before surgery.     

Dynamic measurement of patellofemoral contact pressure following reconstruction of the medial patellofemoral ligament: an in vitro study

BACKGROUND: Surgical reconstruction of the medial patellofemoral ligament used to stabilize the patella against lateral dislocation may concomitantly produce alteration of the patellofemoral contact pressure distribution. Two different tendon transfer techniques of reconstructing the medial patellofemoral ligament, one dynamic and one static, as well as a proximal soft tissue realignment of the patella were investigated. METHODS: Eight human knee specimens were mounted in a kinematic knee simulator and isokinetic extension motion was simulated. Patellofemoral pressure was measured using a pressure sensitive film while a 100 N laterally directed dislocation load was applied to the patella. The specimens were evaluated in a physiologic state, as well as after dynamic reconstruction of the medial patellofemoral ligament using a distal transfer of the semitendinosus tendon, following static reconstruction using a semitendinosus autograft, and following proximal soft tissue realignment of the patella. FINDINGS: Following both reconstruction techniques of the medial patellofemoral ligament patellofemoral contact pressure was not significantly (P=0.49) altered. In contrast, after proximal realignment a trend (P=0.07) towards higher contact pressure near knee extension was observed. In the absence of a lateral dislocation load dynamic and static reconstruction resulted in a medialization (P=0.04) of the center of pressure, whereas under the application of a 100 N dislocation load the center of pressure showed no significant alteration. Following proximal realignment the center of pressure was significantly medialized without (P<0.01) and with a dislocation load (P=0.01) throughout the entire range of knee motion. INTERPRETATION: Static and dynamic ligament reconstruction of the medial patellofemoral ligament did not alter patellofemoral pressure. Proximal realignment, on the other hand, resulted in a constant medialization of the patellofemoral pressure. The data suggest that the reconstruction techniques would be associated with a low risk of causing premature cartilage degeneration due to excessive patellofemoral contact pressure, whereas proximal realignment could cause medial overload of the patellofemoral joint.     

Tibiofemoral kinematics in the transverse and frontal planes influence the location and magnitude of peak patella cartilage stress: An investigation of runners with and without patellofemoral pain

BackgroundTo determine whether the location and magnitude of peak patella cartilage stress varies among runners with and without patellofemoral pain. To determine whether tibiofemoral kinematics in the frontal and transverse planes predict peak lateral and medial patella cartilage stress.MethodsTwelve recreational runners with patellofemoral pain and 10 pain-free controls participated. Peak patella cartilage stress was quantified using finite element models that incorporated subject-specific kinematic and kinetic data obtained during running. Chi-square analysis was used to determine whether the location of peak patella cartilage stress (medial or lateral) varied between groups. Student's t-tests were used to determine whether the magnitude of peak medial and lateral patella cartilage stress varied between groups. In addition, stepwise regression analysis was performed to determine if tibiofemoral kinematics were predictive of peak medial and lateral cartilage stress.FindingsAmong all subjects, 64% exhibited peak cartilage stress on the lateral patella facet. No group differences were found for the location and magnitude of peak cartilage stress on the medial or lateral facets. Tibiofemoral rotation in the transverse plane was the best predictor of peak lateral stress (45% of the variance, r = 0.67). Tibiofemoral rotation in the transverse plane was the best predictor of peak medial stress (44% of the variance, r = −0.67), followed by tibiofemoral rotation in the frontal plane (26% of the variance, r = 0.57).InterpretationsThe location and magnitude of peak patella cartilage stress was similar among runners with and without patellofemoral pain. Tibiofemoral kinematics in the frontal and transverse planes are predictive of cartilage stress on the medial and lateral patella facets.     

Lateral patellofemoral ligament reconstruction to restore functional capacity in patients previously undergoing lateral retinacular release

AIM: To study patient outcomes after surgical correction for iatrogenic patellar instability. METHODS: This retrospective study looked at 17 patients (19 knees) suffering from disabling medial patellar instability following lateral release surgery. All patients underwent lateral patellofemoral ligament (LPFL) reconstruction by a single surgeon. Assessments in all 19 cases included functional outcome scores, range of motion, and assessment for the presence of apprehension sign of the patella to determine if LPFL reconstruction surgery was successful at restoring patellofemoral stability. RESULTS: No patients reported any residual postoperative symptoms of patellar instability. Also no patients demonstrated medial patellar apprehension or examiner induced subluxation with the medial instability test described earlier following LPFL reconstruction. Furthermore, all patients recovered normal range of motion compared to the contralateral limb. For patients with pre and postoperative outcome scores, the mean overall knee injury and osteoarthritis outcome score increased significantly, from 34.39 preoperatively (range: 7.7-70.12) to 69.54 postoperatively (range: 26.82-91.46) at final follow-up (P < 0.0001). CONCLUSION: This novel technique for LPFL reconstruction is effective at restoring lateral restraint of the patellofemoral joint and improving joint functionality.