Proximity of the posterior cruciate ligament insertion to the popliteal artery as a function of the knee flexion angle

Purpose: The purpose of this study was to determine if an optimal knee flexion angle existed that would minimize the risk of neurovascular injury from the passage of transtibial hardware during posterior cruciate ligament (PCL) reconstruction. Type of Study: Cadaveric. Materials and Methods: Fourteen fresh-frozen cadaveric knees were mounted in a Plexiglas apparatus that could be set at 5 different knee flexion angles (0°, 45°, 60°, 90°, and 100°) while joint distention was maintained. Each knee underwent magnetic resonance imaging in the axial and sagittal planes at each of the 5 flexion angles to determine the distance between the PCL tibial insertion and popliteal artery. Results: The mean distance, over all 5 flexion angles, between the PCL insertion and the popliteal artery in the axial plane was 7.6 mm, whereas the mean distance in the sagittal plane was 7.2 mm. There was a significant increase in distance with progressive flexion in both planes. Maximum mean distances were noted at 100° of flexion in both the axial (9.9 mm) and sagittal (9.3 mm) planes. An artificial line mimicking the path of a transtibial drill passed through the popliteal artery in 10 of 10 cases at the 0°, 45°, 60°, and 90° angles, and in 6 of 10 cases at the 100° angle. Conclusions: The results of this study suggest that increasing knee flexion reduces, but does not completely eliminate, the risk of arterial injury during arthroscopic PCL reconstruction.     

Acute popliteal artery occlusion after arthroscopic posterior cruciate ligament reconstruction

Arthroscopic posterior cruciate ligament reconstruction may carry certain risks of complications, including injury to the neurovascular structures in the popliteal region. Acute occlusion of the popliteal artery, a limb-threatening complication, was reported after total knee arthroplasty. We report a case of acute popliteal artery occlusion after arthroscopic posterior cruciate ligament reconstruction. The possible causes included underlying artherosclerosis, the use of pneumatic tourniquet, surgical manipulation, and arterial spasm. Early diagnosis and prompt surgical treatment are the keys to success in the treatment of this limb-threatening complication. Spontaneous resolution of the thrombus such as is reported in this case is exceptional.     

The posterior cruciate ligament during flexion of the normal knee

The posterior cruciate ligament (PCL) was imaged by MRI throughout flexion in neutral tibial rotation in six cadaver knees, which were also dissected, and in 20 unloaded and 13 loaded living (squatting) knees. The appearance of the ligament was the same in all three groups. In extension the ligament is curved concave-forwards. It is straight, fully out-to-length and approaching vertical from 60 degrees to 120 degrees, and curves convex-forwards over the roof of the intercondylar notch in full flexion. Throughout flexion the length of the ligament does not change, but the separations of its attachments do. We conclude that the PCL is not loaded in the unloaded cadaver knee and therefore, since its appearance in all three groups is the same, that it is also unloaded in the living knee during flexion. The posterior fibres may be an exception in hyperextension, probably being loaded either because of posterior femoral lift-off or because of the forward curvature of the PCL. These conclusions relate only to everyday life: none may be drawn with regard to more strenuous activities such as sport or in trauma.     

Effects of knee flexion angle at graft fixation on the outcome of anterior cruciate ligament reconstruction

Clinical outcome in 44 patients who underwent anterior cruciate ligament (ACL) reconstruction with hamstring tendons augmented by the ligament augmentation device for chronic ACL deficiency was studied; average follow-up was 38 months (range, 24 to 52 months). In 19 patients, grafts were fixed with the knees at full extension (group 1), whereas in 25 patients, the grafts were fixed with the knees at 30° of flexion (group 2). The results of subjective testing (Lysholm score), the Lachman test, the pivot-shift test, muscle strength testing, angle of extension loss, and follow-up arthroscopy were compared to assess the effects of flexion angle at fixation on stability and function. The range of motion in group 1 was significantly better than that in group 2. The stability of the knees and the arthroscopic appearance of the grafts in group 1 were, however, significantly worse than those in Group 2.     

Isolated posterior cruciate ligament rupture presenting as a locked knee

Mechanical symptoms in the knee, especially locking, are most commonly associated with meniscal pathology. We present an atypical case of locking of the knee secondary to an isolated posterior cruciate ligament tear.     

Proximity of the popliteal artery to the PCL during simulated knee arthroscopy: implications for establishing the posterior trans-septal portal

This study defines the sagittal distance from the posterior cruciate ligament (PCL) to the popliteal artery under simulated arthroscopic conditions. This information is relevant for posterior knee arthroscopy, particularly for the safe establishment of the posterior trans-septal portal. Measurements from the PCL to the popliteal artery were made on sagittal magnetic resonance images obtained in a previous study of 10 fresh-frozen cadaveric knees. The mean sagittal distance from the mid-PCL to the popliteal artery was 29.1 +/- 11 mm (range: 18-55 mm). The mean sagittal distance from the proximal PCL fovea to the popliteal artery was 9.7 +/- 5 mm (range: 3-16 mm). The results of this study provide the arthroscopist working in the posterior compartments of the knee with a more detailed knowledge of the anatomic relationship between the PCL and popliteal artery. This knowledge will help minimize the risk of iatrogenic vascular injury during arthroscopic knee surgery.     

膝前、后交叉韧带与内侧副韧带损伤的一期修复重建

目的探讨膝关节镜下重建前、后交叉韧带联合有限切开修复内侧副韧带恢复膝关节稳定和功能的疗效。方法 2003年4月-2010年10月,收治14例(14膝)前、后交叉韧带伴内侧副韧带损伤患者。男10例,女4例;年龄21～71岁,平均41岁。致伤原因:交通事故伤11例,高处坠落伤3例。患者受伤至入院时间为1～4 d,平均2 d。Lysholm评分为(17.00±8.29)分,国际膝关节文献委员会(IKDC)评分为(20.93±8.28)分。伴膝关节脱位9例,半月板损伤5例。关节镜下采用同种异体肌腱(2例)或自体腘绳肌腱(12例)重建前、后交叉韧带,有限切开修复内侧副韧带。结果术后切口均Ⅰ期愈合;3例出现下肢麻木,自行缓解。患者均获随访,随访时间为12～18个月,平均14个月。患者膝关节均于3个月内达屈曲120°,伸直0°。术后1年膝关节IKDC评分为(89.93±6.26)分,Lysholm评分为(88.93±4.82)分,与术前比较差异有统计学意义(P<0.01)。结论对于膝关节韧带多发伤,关节镜配合有限切开修复重建韧带,避免了开放关节腔,同时由于创伤小,术后关节粘连轻,关节功能恢复快。     

屈髋屈膝位膝关节后内侧横行小切口治疗后交叉韧带胫骨止点撕脱骨折

目的:评价应用屈髋屈膝位膝关节后内侧横行小切口治疗后交叉韧带胫骨撕脱骨折的方法及疗效。方法:对2010年3月至2013年3月应用屈髋屈膝位膝关节后内侧横行小切口切开复位、空心螺钉固定治疗的21例后交叉韧带胫骨撕脱骨折患者进行回顾性分析,男13例,女8例;年龄20~56岁,平均35.1岁;交通事故伤11例,坠落伤3例,运动伤4例,重物砸伤3例;伤后至手术时间3 h~9 d,平均3.5 d;后抽屉试验均为阳性。采用膝关节Lysholm评分评价膝关节功能。结果:手术过程均顺利,无腘窝血管神经损伤。切口长度5~6 cm,平均5.8 cm。术后检查抽屉试验阴性,复查X线均证实骨折复位。21例均获随访,时间7~23个月,平均12.7个月。骨折均骨性愈合,膝关节Lysholm评分由术前的40.76±9.55提高至末次随访时的95.86±2.33(t=30.07,P=0.000)。结论:屈髋屈膝位膝关节后内侧横行小切口治疗后交叉韧带胫骨止点撕脱骨折是是简便、安全的手术方法,可有效显露骨折区域,手术创伤小,愈合后瘢痕小,疗效满意。     

骨科手术机器人辅助重建急性后交叉韧带断裂1例

正患者,男,63岁,因"外伤致左膝肿痛伴活动受限2 d"入院。患者2 d前骑车摔伤致左膝部剧烈锐痛,持续不缓解,肿胀明显,活动后加重,休息未见明显缓解,能行走,但是跛行明显,就诊我院,行MRI示左膝后交叉韧带撕裂,左膝内侧副韧带撕裂(图1a)。诊断为左膝后交叉韧带(posterior craciate liga-ment,PCL)撕裂,左膝内侧副韧带撕裂。     

Dorsal approach for reconstruction of the posterior cruciate ligament

The operative treatment of a posterior cruciate ligament rupture through a straight central approach in the hollow of the knee is decribed. Following evaluation of the different operative procedures used in our clinic during the years of 1977 through 1990, this is now the preferred technique. The results of the different procedures are summarized. Clinical follow-up examinations were carried out in 75 patients operated on between 1977 and 1990, after a mean postoperative follow-up period of 6 years. For each patient the clinical results were evaluated both subjectively and objectively using OAK-scores and the KT-1000 arthrometer. Out of 75 patients, 43 whose injury had occurred more than 5 years earlier were post-examined radiologically. Rupture of the posterior cruciate ligament is rare compared with rupture of the anterior cruciate ligament, and the outcome after operative treatment is very often unsatisfactory. Since Mayo Robson carried out the first open reconstruction of a posterior cruciate ligament rupture, countless methods for operative stabilization have been described. On the basis of our experience of various operating procedures used during the years 1977 through 1990, reconstruction of the posterior cruciate ligament through a dorsal access is now our procedure of choice.     

In vivo function of posterior cruciate ligament before and after posterior cruciate ligament-retaining total knee arthroplasty

Purpose

The object of this study was to investigate the in vivo function of the posterior cruciate ligament (PCL) in patients before and after a PCL-retaining total knee arthroplasty (TKA).

Methods

Eleven patients with advanced osteoarthritis (OA) of the knee were recruited. Magnetic resonance scans of each OA knee were obtained, and 3D computer models, including the femoral and tibial insertion areas of the anterolateral and posteromedial bundles of the PCL, were created. Before and after PCL-retaining TKA, dual fluoroscopic images of each knee were acquired during weight-bearing knee flexion. The images and computer models were used to reproduce the in vivo motion of the knee. The function of the PCL bundles was described in terms of elongation, elevation and deviation. Twenty-two healthy controls were also included as normal references.

Results

PCL bundles of the OA knees were overstretched during late knee flexion and orientated more medially throughout flexion compared with normal knees. After PCL-retaining TKA, PCL bundles were further overstretched during late flexion and changed from medially directed in normal and OA knees to almost sagittally directed, which may compromise function in controlling knee rotation.

Conclusions

The current PCL-retaining TKA systems and surgical techniques may not adequately re-establish normal biomechanics of PCL bundles after PCL-retaining TKA.     

膝关节后交叉韧带合并后外侧角结构损伤的联合重建

目的 探讨膝关节后交叉韧带(PCL)合并后外侧角结构(PLC)实质部损伤时进行联合重建的必要性,介绍使用关节镜下5～6股腘绳肌腱单束重建膝PCL以及采用中1/3股二头肌腱、股薄肌重建PLC的技术和优点. 方法 自2001年1月至2006年12月,收治膝关节PCL合并PLC损伤患者28例,均为PCL损伤≥Ⅱ°b、PLC损伤>Ⅱ°.X线片有韧带附着点撕脱骨折及严重内翻不稳需要胫骨截骨者不计入本组.治疗方法:手术治疗28例,其中2002年1月至2003年12月间8例行关节镜下腘绳肌腱单束重建PCL,而PLC保守治疗;2002年1月至2006年12月间20例关节镜下修复重建PCL,再开放手术操作修复重建PLC结构. 结果 随访6～24个月,平均15个月.功能评定按照Lysholm标准,单纯修复PCL组中等3例,差5例;PCL和PLC联合重建者中优良19例,中等1例.两组的Lysholm评分平均为(47.1±8.2)分和(86.7±7.2)分,差异有统计学意义(t=19.277,P<0.05);IKDC评估两组分别有3例和19例对手术结果满意.无严重并发症发生. 结论 膝关节PCL合并PLC损伤可造成患肢严重的无法代偿的功能损害,手术时应当进行联合重建,忽视PLC重建的重要性,会导致PCL重建效果下降或失败;采用关节镜下5～6股腘绳肌腱单束重建膝PCL以及采用中1/3股二头肌腱、股薄肌重建PLC的技术治疗PCL合并PLC损伤取得较好的临床效果.     

Pseudoaneurysm of the popliteal artery after anterior cruciate ligament reconstruction with bicortical tibial screw fixation

We present a case report of a pseudoaneurysm of the popliteal artery after anterior cruciate ligament reconstruction using a bicortical tibial screw fixation 12 days after surgery. Surgical exploration and repair of an intimal lesion of the popliteal artery was performed. At 4-months’ follow-up, there was still sensory loss in areas of the saphenous, medial plantar, calcaneal, and superficial peroneal nerves.     

膝后内侧入路修复重建后交叉韧带(附24例报道)

目的介绍并探索膝后内侧入路修复重建后交叉韧带(PCL)的特点和技术要点。方法用膝后内侧“S”形入路修复PCL13例,取半腱肌腱重建PCL11例;俯卧位手术16例,仰卧位手术8例。对后内侧入路的应用解剖、手术要点及效果进行评价。结果后内侧入路不需要显露血管神经,比膝后入路平均手术时间缩短30～60分钟,不受体位限制,不需附加切口,一个切口既可修复又可重建PCL。21例患者经半年以上随访膝关节不稳无复发。结论膝后内侧入路简单、安全、显露好,是修复重建PCL的理想入路,抽出钢丝法和取半腱肌腱拉出“U”形钉固定是修复和重建PCL的首选方法。     

In vitro study of knee stability after two-band two-tunnel posterior cruciate ligament reconstruction

Objective: To compare the ability of three different reconstruction procedures in restoring the posterior displacement of tibia and the posterior stability of the knee joint from 0°to 120°flexion. Methods: Three posterior cruciate ligaments (PCL) reconstruction procedures were performed, namely two-band two-tunnel reconstruction, one-band anterior tunnel reconstruction and one-band posterior tunnel reconstruction. The posterior displacement of the tibia in relation to the femur was measured when a 200 N posterior force was applied. Results: Within the flexion range of 0°to 30°, the displacement in the one-band posterior tunnel reconstruction showed little difference from that of an intact knee (P>0.05). But when the flexion exceeded 30°, especially when it exceeded 60°, the displacement in one band posterior tunnel reconstruction was much greater than that of an intact knee (P<0.01). In two-band two-tunnel reconstruction and one-band anterior tunnel reconstruction, the displacement was approximately the same as that of an intact knee ranging from 0°to 120°(P>0.05), while a slight over-restriction might be found at some angles. Conclusions: Two-band reconstruction could effectively restrict the posterior displacement of the tibia and restore anterior, posterior stability of the knee joint within its full range of flexion. One-band anterior tunnel reconstruction also could maintain the posterior stability of the knee, while the result of one-band posterior tunnel reconstruction is the most unsatisfactory.     

后十字韧带单束重建联合小切口切开腘腓韧带重建治疗严重膝关节不稳定

目的 评估后十字韧带(posterior cmciate ligament,PCL)单束重建联合小切口切开腘腓韧带(popliteofibular ligament,PFL)重建治疗严重的膝关节后向和后外旋转不稳定的临床结果.方法 自2003年7月至2007年4月,共有28例连续的患者接受关节镜下PCL单束重建联合小切口切开PFL重建手术.人选条件:所有患者均为严重的膝关节不稳定,后抽屉试验为3~+或以上,胫骨后移程度与健侧相比≥12mm,胫骨外旋程度大于健侧10°以上,同时不合并外侧副韧带的损伤.入选的患者接受关节镜下单束PCL重建,使用异体跟腱作为移植物.在膝关节外侧通过两个小切口切开,使用异体胫前肌腱重建PFL.股骨侧切口位于股骨外上髁,长度为2cm;腓骨侧切口位于腓骨头,长度为3 cm.结果 术后平均随访时间为39.7个月.使用膝关节应力像评估后向稳定性,胫骨后移程度(患侧与健侧的差值)由术前(17.7±4.5)mm减小为术后(4.5±3.9)mm,胫骨外旋程度(患侧与健侧的差值)由术前16.0°±4.7°减小为术后-2.8°±6.4°,术前与术后的差异有统计学意义.IKDC评分:术前28例均为D级,术后A级为10例,B级9例,C级8例和1例D级.结论 关节镜下PCL单束重建联合使用小切口切开PFL重建能够有效地改善膝关节后向和后外旋转不稳定.