Pathological infrapatellar Plica: A report of two cases and literature review

In two cases of flexion contracture of knees, the vertical septum pattern of the infrapatellar plica was noted arthroscopically to be thickened, fibrotic, and to have lost its clasticity. The pliacac were impinged to the intercondylar notch and trochlea at extension of the knees, blocking further extension. The pathological plicae were resected, followed by improvement in range of the extension of the knees. At 6 months postoperatively, the knees gained full extension. This is the first report showing that the infrapatellar plica caused a clinical symptom.     

The development of synovial plicae in human knee joints: An embryologic study

An embryologic study about the development of the human knee joint cavity was carried out with special attention to the formation of synovial plicae, using a total of 116 knees of embryos and fetuses. The incidence of synovial plicae in the fetal stage was also investigated. Formation of joint space starts at the middle of the interzone at around 8 weeks of gestation. Multiple small cavitations around the femoral condyle and patella coalesce to form larger cavitations. At around 10 1/2 weeks, the knee joint consists of a single cavity with synovial lining. At certain sites, such as at the medial part of patello-femoral and the infrapatellar regions, mesenchymal tissue strands remain. They may become plica. In the fetal stage from 11 to 20 weeks, an infrapatellar plica was found in 50% of specimens, a suprapatellar plica in 33%, and a mediopatellar plica in 37%. Only the infrapatellar plica showed a decrease in incidence.     

膝关节髌下皱襞的临床意义

目的:观察膝关节镜下髌下皱襞结构的变化,探讨膝关节髌下皱襞的临床意义。方法:回顾性总结分析膝关节镜手术病例400例,男177例,女223例;年龄9~79岁,平均42岁。术前均有膝关节疼痛、肿胀和交锁等现象,保守治疗无效,行膝关节镜检查及镜下手术。术中证实单纯的髌下皱襞病变11例,术前有膝前区疼痛症状者8例,疼痛区域模糊不定者3例,膝关节反复肿胀、积液者2例;术前诊断为半月板损伤4例,关节软骨损伤2例,髌股关节骨性关节炎1例,髌下脂肪垫损伤4例。11例均行膝关节镜下髌下皱襞切除术。结果:400例膝关节镜手术中发现有髌下皱襞结构的284例(71%);有髌下皱襞病变的52例(13%),其中单纯的髌下皱襞病变11例(2.75%)。髌下皱襞病变镜下表现为髌下皱襞肿胀、增厚、纤维化、丧失弹性,与髁间凹产生撞击。11例单纯髌下皱襞病变均行关节镜下髌下皱襞切除术,术后随访9例,2例失访,随访时间3~24个月,平均14个月。疗效评定优7例,良1例,可1例,差0例,优良率88.89%。结论:髌下皱襞具有明确的临床意义,其病变可以引起临床症状。     

膝关节髌下皱襞的临床意义

目的:观察膝关节镜下髌下皱襞结构的变化,探讨膝关节髌下皱襞的临床意义。方法:回顾性总结分析膝关节镜手术病例400例,男177例,女223例;年龄9⁷9岁,平均42岁。术前均有膝关节疼痛、肿胀和交锁等现象,保守治疗无效,行膝关节镜检查及镜下手术。术中证实单纯的髌下皱襞病变11例,术前有膝前区疼痛症状者8例,疼痛区域模糊不定者3例,膝关节反复肿胀、积液者2例;术前诊断为半月板损伤4例,关节软骨损伤2例,髌股关节骨性关节炎1例,髌下脂肪垫损伤4例。11例均行膝关节镜下髌下皱襞切除术。结果:400例膝关节镜手术中发现有髌下皱襞结构的284例（71%）;有髌下皱襞病变的52例（13%）,其中单纯的髌下皱襞病变11例（2.75%）。髌下皱襞病变镜下表现为髌下皱襞肿胀、增厚、纤维化、丧失弹性,与髁间凹产生撞击。11例单纯髌下皱襞病变均行关节镜下髌下皱襞切除术,术后随访9例,2例失访,随访时间3²4个月,平均14个月。疗效评定优7例,良1例,可1例,差0例,优良率88.89%。结论:髌下皱襞具有明确的临床意义,其病变可以引起临床症状。     

Arthroscopic treatment of symptomatic type D medial plica

We aimed to review the results of subtotal arthroscopic resection of symptomatic type D medial plica. We retrospectively evaluated 23 knees with symptomatic type D medial plica in 22 patients without other intra-articular pathology. All patients complained of chronic knee pain that had not been alleviated by medical treatment or physical therapy. In only three (13%) of the patients studied was the plica diagnosed pre-operatively with magnetic resonance imaging. The type D medial plicae in our series were classified as fenestrated (14 knees), torn (5 knees), or reduplicated (4 knees). Fibrotic changes in the plicae and degenerative changes on the medial femoral condyle were found in 16 knees Patellofemoral chondromalacia was present in three knees Arthroscopic partial resection was performed in all patients. Comparative Lysholm Knee Scale scores before and after surgery revealed a significant clinical improvement (pre-operative status, 67.19 ± 8.05 vs. post-operative status, 90.57 ± 9.80; P < 0.001). Type D medial plica should be considered as a possible cause of chronic knee pain. Arthroscopic partial resection of the plicae in symptomatic patients gives satisfactory results. Research was performed at the Medical Faculties of Baskent University and Istanbul University.     

Anatomy of the medial suprapatellar plica and medial synovial shelf

The anatomy of the medial suprapatellar plica and medial synovial shelf was studied arthroscopically in 500 knees. The medical suprapatellar plica extended up to one third of the way across the suprapatellar pouch in 64.2% of knees, between one and two thirds in 4%, and two thirds or more in 31.6%. The medial synovial shelf was absent or vestigial in 36% of knees and broader than 1 cm in 13.2%. When both knees were examined arthroscopically, the similarity between the appearances of the plica and the shelf in the two knees was statistically significant. No relationship between age and the pattern of plica or shelf could be found. There was no association between large plicae and large shelves, but the shelf was absent significantly more often in knees with a narrow plica.     

The clinical significance of the complete type of suprapatellar membrane

The plicae are synovial septa remaining in adult life that existed in early fetal life. The suprapatellar plica separates the suprapatellar pouch from the knee joint. The plica syndrome has clinical significance, which has been occasionally overlooked, but the pathophysiology of symptomatic plicae may be hard to explain. To evaluate the clinical significance of the suprapatellar plicae, the authors reviewed 34 cases in 23 patients with vague pain around the knee and a total septum of the suprapatellar plica at arthroscopic examination from September 1991 to December 1993. The follow-up period was from 6 months to 2 years and 9 months. The most common presenting symptom was chronic mild knee pain, aggravated by prolonged squatting or standing, with other patients reporting recurrent swelling, instability, giving-way, or a feeling of snapping. The objective findings include palpable band on the superomedial side, audible snapping, and local tenderness, but there were no significant abnormal findings in the laboratory. The radiographic findings were few, with sclerosis of the articular surface of the patella in 2(6%), malalignment in 1(3%), and mild degenerative change in 4 cases(12%). Five of 11 patients evaluated by bone scan had increased uptake around the patellofemoral joint, and 7 of 13 knees had a relatively small suprapatellar bursa on conventional arthrogram or pneumoarthrogram. At arthroscopy, a suprapatellar plicae with complete septum was identified in 30 of 34 cases (88%) and associated lesions presented as meniscal tears, loose body, and discoid meniscus without tear. The complete plicae were surgically excised under arthroscopic control in 30 patients and the results were excellent in 22 patients (73%), good in 5 (17%), and poor in 3 (10%)at 17 months follow-up; there were no failures. In our opinion, the complete suprapatellar plica is clinically significant in patients who have equivocal diagnosis of knee problems and further studies of the pathophysiology of complete suprapatellar plica are needed. (Arthroscopy 1998 Nov-Dec;14(8):830-5.)     

军训伤致膝关节滑膜皱襞综合征

目的　总结 2 3例、 2 6膝军训所致膝关节滑膜皱襞综合征的诊疗体会。方法　对该疾患采用关节镜下剪除或联合小切口手术切除病变皱襞。结果　 2 3例中 2 0例 2 2膝随诊 6个月～ 1年 ,其中优 18膝 ,良 3膝 ,可 1膝 ,优良率为 95 . 4%。结论　认为关节镜可以确诊 ,关节镜下或联合小切口手术切除病变皱襞是治疗的有效方法。     

Clinical diagnosis of medial plica syndrome of the knee: a prospective study

Clinical diagnosis of symptomatic medial plica that causes anteromedial knee pain is poorly defined in the literature; therefore, arthroscopy is considered to be the gold standard for diagnosing this condition. We report our system of clinical diagnosis for medial plica syndrome that is based on patient history and our criteria for clinical examination. This prospective study included 48 symptomatic patients (66 knees) with clinical suspicion of pathological medial plica based on five essential and four desirable criteria. All patients underwent arthroscopic examination to confirm or disprove the clinical diagnosis and also treatment. Arthroscopy confirmed the clinical diagnosis of medial plicae in 44 patients (62 knees) for a diagnostic accuracy of 91.7% (95% confidence interval [CI]: 80% to 97.7%) and sensitivity of 100% (95% CI: 92% to 100%). The 44 patients with pathological medial plicae at arthroscopy were treated by arthroscopic resection. Thirty-nine patients (55 knees) showed satisfactory outcome after arthroscopy (95% CI: 75.4%, 96.2%). Our method of clinical diagnosis of pathological medial plica is simple, inexpensive, noninvasive, and reliable. We conclude arthroscopy is successful in treating this condition.     

Subacromial plica as a cause of impingement in the shoulder

The subacromial bursa is the largest bursa in the body. In 1934, Codman described the presence of subacromial plicae, similar to the suprapatellar plicae found in the knee. It is recognized that plicae in the knee can cause anterior knee pain with impingement against the patella in young persons. We investigated the possibility that a similar situation exists with plicae of the subacromial bursa. The aims of this study were to document the prevalence of bursal plicae seen at bursoscopy during arthroscopic subacromial decompression of the shoulder and to assess whether there is any pattern in the occurrence of these plicae, as well as the relationship to impingement lesions seen at bursoscopy. Between January 1996 and July 2001, all cases undergoing arthroscopic decompression were evaluated for anatomic-pathologic changes of the subacromial bursa, including the presence of plicae and impingement lesions. A total of 1732 cases complying with inclusion criteria were recorded, with plicae observed in 104 (6.0%). The occurrence of plicae showed a highly significant younger age predilection (P = .0008, chi(2) test) but no differences between sexes or sides. The occurrence of subacromial plicae was highly associated with the combined severity of the impingement lesion on the acromial and bursal side. Plicae were most common in shoulders showing an impingement lesion on the cuff bursal side, with no impingement lesion on the acromial side. The odds of the impingement lesion being milder on the acromial side was 3.41 times higher in shoulders with a plica compared with shoulders without a plica. This suggests that impingement of the cuff may be due to the plica itself. This study is the first to describe the presence of subacromial plicae in living subjects and correlates with previous anatomic studies. The younger age predominance correlates with the findings of plicae in the knee. Our findings suggest that subacromial plicae may be a cause of impingement in young patients.     

Arthroscopic studies of variants of the anterior horn of the medial meniscus

The objective of this study was to arthroscopically analyse the morphology and dynamics of variants of the anterior horn of the medial meniscus of the knee (VAMM) and to then consider the pathological significance of these variants. VAMM was defined as knees in which the anterior horn of the medial meniscus is not attached to the tibia. Between April 1992 and March 1995, arthroscopy was performed on 953 knees of 903 patients. At the time of this examination, observation and probing were performed to determine the condition of the synovium, the synovial plica, the cartilage in all compartments, the meniscus, the cruciate ligaments, and the popliteal tendon. In particular, detailed examination was made of the anterior horn of the medial meniscus with regard to the point of insertion to the tibia and the degree of movement in knee flexion/ extension. Cases of VAMM diagnosed on the basis of the arthroscopic findings were classified into the following four categories: the ACL (anterior cruciate ligament) type, where the anterior horn of the medial meniscus was attached to the ACL; the transverse ligament type, where the anterior horn of the medial meniscus was attached to the transverse ligament; the coronary ligament type, where the anterior horn of the medial meniscus was attached to the coronary ligament; and the infrapatellar fold type, where the anterior horn of the medial meniscus was attached to the infrapatellar synovial fold. These patients were then analyzed with regard to the arthroscopic findings and the intra-articular lesions other than VAMM. In 98 (10.9%) of the total patients, 103 knees were classified as VAMM. Classification of those 103 knees using the above criteria showed 39 ACL type knees, 51 transverse ligament type knees, 11 coronary ligament type knees, and 2 infrapatellar fold type knees. The arthroscopic findings indicated that the anterior horn of the medial meniscus was not attached directly to the tibia in any of these knees. Probing and flexion/extension of the knee revealed hypermobility at the anterior horn of the medial meniscus. In this study, anterior knee pain syndrome was diagnosed in 12 (11.7%) of the 103 VAMM knees. In addition, there was no clear history of trauma in 20 of 23 knees found to have an isolated medial meniscus tear. In these cases, even detailed arthroscopic observation proved the causes of the symptoms or injury. On the basis of these findings, we surmised that the anterior portion shows hypermobility at the time of flexion/extension of the knee, regardless of the type of VAMM. In this study, we discussed the possibility that the existence of VAMM may become the cause of pain or injury to the meniscus.     

膝关节滑膜皱襞综合征发生机理探讨

目的:观察分析膝关节滑膜皱襞综合征的发生机理,探讨滑膜皱襞综合征的发生率、发生原因与年龄的关系,皱襞的部位、类型与临床症状体征的关系。方法:分组观察皱襞综合征的发生率及其发生原因的异同。结果:滑膜皱襞总发生率为56.78％,分组比较中老年组滑膜皱襞综合征发生率高于中青年组(P<0.05)。发生原因比较,中青年组创伤原因高于中老年组(x~2=38.33,P=0.000),磨擦退化原因,中老年组高于中青年组(x~2=45.53,P=0.000)。滑膜皱襞出现部位以髌内侧为主(74.50％),分型以C型和B型为主(91.84％)。结论:膝关节滑膜皱襞综合征以中老年多见,其中磨擦退化原因占39.70％,提示有必要将磨擦退化列为中老年滑膜皱襞综合征的发生原因之一。滑膜皱襞的部位及分型与临床症状体征相关并具有一定的临床特点。     

髌内侧滑膜皱襞中表达P物质的神经分布与髌股关节痛的相关性

目的 研究病理件髌内侧滑膜皱襞中神经解剖结构变化.证实表达P物质的神经纤维分布增多足病理性髌内侧滑膜皱襞引起髌股关节痛的结构基础.方法 通过膝关节镜获取滑膜皱襞标本,采用免疫组化半定量分析方法观察P物质在膝关节髌内侧滑膜皱襞中的分布规律、变化趋势,比较空白对照组(无症状的滑膜皱襞)、阳性对照组(有症状的滑膜皱襞合并其他损伤)、实验组(有症状的滑膜皱襞)共51例患者髌内侧滑膜皱襞中表达P物质的神经纤维分布密度.结果 空白对照组髌上滑膜皱襞P物质染色阳性神经纤维密度为(24.60±26.17)根/cm2;阳性对照组为(117.36±73.62)根/cm2,实验组为(59.06±44.06)根/cm2.实验组髌内侧滑膜皱襞P物质染色阳性神经纤维密度为(255.44±87.91)根/cm2,阳性对照组为(268.00±71.60)根/cm2,空白对照组为(23.23±18.41)根/cm2.髌内侧滑膜皱襞神经纤维密度高于髌上滑膜皱襞.实验组与阳性对照组髌内侧滑膜皱襞中P物质染色阳性神经纤维密度均高于空白对照组,阳性对照组高于实验组.P物质神经纤维分布密度与VAS疼痛评分呈正相关.结论 病理性髌内侧滑膜皱襞中表达P物质的神经纤维分布密度与患者疼痛程度呈正相关.病理性髌内侧滑膜铍襞中表达P物质的伤害性疼痛感觉神经纤维是疼痛发生的重要神经病理学基础,是髌内侧滑膜皱襞综合征发病机制中的重要环节.     

膝关节内侧滑膜皱襞综合征的关节镜诊治

目的探讨膝关节内侧滑膜皱襞综合征的临床诊断、关节镜诊断及疗效。方法回顾分析1996年1月～2007年12月收治的420例诊断为膝关节痛或半月板损伤或滑膜皱襞综合征的患者,其中有70例内侧滑膜皱襞综合征患者。按Sakakibara法分析其关节镜下形态,在镜视下行皱襞切除术、挛缩内侧支持带松解术,随访分析其疗效。结果70例内侧滑膜皱襞综合征中,镜下A型8例,B型13例,C型24例,D型25例。经镜下行皱襞切除,获得随访43例,随访时间为6个月～5年,平均32个月,按Lysholm法进行疗效评定,优良率90.7%。结论关节镜仍是该病确诊的"金标准",镜下彻底切除滑膜皱襞、松解挛缩内侧支持带是治疗该病有效的方法。     

Segmental arthroscopic resection of the hypertrophic mediopatellar plica

In a retrospective review of 64 knees (58 patients) treated during a 36-month period by segmental arthroscopic resection of a hypertrophic mediopatellar plica, each patient was questioned and/or examined a minimum of one year after surgery. Medial or retropatellar pain (95%), buckling (32%), swelling (25%), and snapping (16%) were symptoms associated with a hypertrophic mediopatellar plica. Findings during physical examination of medial and retropatellar tenderness (74%) suggest the presence of the condition. Thirty percent of knees had localized chondromalacia of the medial femoral condyle, while in 13% chondromalacia was localized to the medial patellar facet. Good to excellent results were obtained in 86% of knees with a hypertrophic mediopatellar plica, with or without localized chondromalacia. In patients who had associated conditions, the lesions were also treated arthroscopically; good to excellent results were obtained in 69% of these knees.     

膝关节滑膜皱襞综合征的解剖与临床23例观察

对200侧胎儿膝关节滑膜皱襞的形态学进行观察,结果表明,膝关节滑膜皱襞有各种形状,主要存在三个部位,髌上滑膜皱襞发生率为99.5%;髌内侧滑膜皱襞发生率为70%;髌下滑膜皱襞发生率为100%.依照结果,作者自1990年～1994年共手术治疗膝关节滑膜皱襞综合征23例.21例经1.5年以上随访,15例临床症状消失,6例基本消失,治疗效果满意.     

病理性滑膜皱襞组织神经解剖结构的分布规律研究

目的观察研究膝关节髌内侧滑膜皱襞综合征（MPS）患者病理性滑膜皱襞组织中神经解剖结构的分布规律。方法 膝关节镜下采集2007年5月至2008年11月实验组（MPS）20例和对照组11例（无症状滑膜皱襞）患者的髌内侧滑膜皱襞,采用LsAB和免疫荧光法进行蛋白基因产物9.5（PGP9.5）、P物质（SP）免疫组化染色,半定量测量神经分布区域密度,采用t检验比较实验组和对照组神经分布密度差异,采用配对t检验比较皱襞游离缘和基底部之间神经密度的差异。结果 （1）膝关节髌内侧滑膜皱襞中存在神经纤维的分布：神经结构主要呈游离神经纤维、神经纤维束、血管周围神经网络三种主要的形态存在,走行与血管相伴,主要分布于血管周围区域。（2）实验组PGP9.5阳性纤维密度（纤维/cm2）：滑膜皱襞游离缘为（190.17±91.66）,基底部为（334.39±115.68）;SP染色阳性纤维密度在游离缘为（153.63±100.73）,基底部为（282.95±126.10）。对照组PGP9.5阳性纤维密度为（37.65±22.91）;SP阳性纤维密度为（23.23±18.41）。两种神经染色方法均证实：（1）MPS组患者髌内侧滑膜皱襞中阳性纤维密度与对照组间的差异有统计学意义（P〈0.01）;（2）病理性髌内侧滑膜皱襞基底部阳性纤维密度明显高于游离缘（P〈0.01）。结论 膝关节髌内侧滑膜皱襞中存在神经纤维的分布,在引起髌股关节疼痛的病理性髌内侧滑膜皱襞中神经纤维分布明显增多,其分布规律为：皱襞基底部的神经纤维数明显高于游离缘;表达与疼痛的产生和传导密切相关的P物质染色阳性的感觉神经纤维明显增多提示髌内侧滑膜皱襞基底部区域是产生髌股关节疼痛的高危区域。     

Atraumatic hemarthrosis caused by a large mediopatellar plica

Hemarthrosis of the knee has various etiologies and is classified into atraumatic or post-traumatic. Among atraumatic factors, hemarthrosis due to synovial plica is extremely rare. We report a case of atraumatic hemarthrosis caused by the mediopatellar plica. A 21-year-old male truck driver was referred to our hospital, because of swelling and pain of the right knee without history of trauma. Bloody synovial fluid was aspirated by arthrocentesis. However, his symptoms recurred and persisted. The range of motion was normal, but the patient complained of anteromedial knee pain during maximum flexion. Routine biochemical analyses were within normal limits. Plain radiographs were normal. Magnetic resonance imaging (MRI) of the knee showed the hypertrophic mediopatellar plica and an irregular signal of the infrapatellar fat pad. Arthroscopy revealed a voluminous mediopatellar plica trapped between the patella and the medial femoral condyle. It attached to the center of the infrapatellar fat pad, the so-called tongue. When the tourniquet was released, fresh bleeding was observed from the region between the mediopatellar plica and the tongue. Because that region was considered to be the cause of the hemarthrosis, the mediopatellar plica and the tongue were excised. A histologic examination of the tongue showed evidence of bleeding with nonspecific synovitis. After the procedure, the patient was asymptomatic and there were no clinical signs of recurrence.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 17, No 4 (April), 2001: pp 415–417     

髌内侧滑膜皱襞综合征为主的膝关节内紊乱

目的:通过临床病例观察,探讨膝内侧滑膜皱襞综合征的诊断、类型及与半月板损伤、软骨损害的关系,分析膝内侧滑膜皱襞综合征的特点及在骨性关节炎发病中所起的作用。方法:关节镜下治疗内侧滑膜皱襞综合征患者48例(53膝),其中男13例(13膝),女35例(40膝);年龄16~71岁,平均56岁;病程1个月~10年,平均26个月。48例于关节镜直视下观察并手术切除滑膜皱襞,处理相应病变。采用Lysholm膝关节量表记分法评价疗效。观察症状体征与实际病损的关系,计算术前与术中诊断的符合率。关节镜下观察症状性滑膜皱襞的部位、性状、分型及软骨磨损的部位和分级,分析增生的滑膜皱襞与半月板损伤、软骨损害的关系。对术前后Lysholm评分采用SPSS13.0统计软件进行统计学处理。结果:常见的软骨缺损有股骨内髁内侧的沟槽状缺损及股骨内侧滑车的类圆形缺损。软骨退变以股骨内髁非负重区为主,占总数的54.29%;以股骨滑车内侧次之,占40.00%;以髌骨内侧关节面为主的缺损居第3位,占5.71%。术后48例53膝均获随访,随访时间17个月~4年,平均28个月。Lysholm膝关节评分:术前平均(41.00±7.03)分,术后平均(85.00±8.01)分(t=-26.17,P<0.001),证明关节镜治疗效果显著。本组优(>90分)12膝,良(80~90分)37膝,可(70~79分)4膝,优良率92.45%,无复发及二次手术者。结论:通过关节镜下特征性改变可以对内侧滑膜皱襞综合征做出明确诊断,股骨内髁及滑车软骨的沟槽状及类圆形磨损是2种典型的皱襞引起的软骨缺损。镜下切除滑膜皱襞疗效满意,对防止软骨进一步损害有积极的意义。     

Clinical symptoms caused by intra-articular fibrous plicae after knee replacement

In 29 patients with persistent complaints after knee replacement we found infra-articular fibrous tissue in different areas of the joint. In 26 patients diagnostic arthroscopy was followed by arthroscopic resection of the tissue. The fibrous tissue was differentiated into five types. Type 1 represented a transverse fibrous band located at the superior margin of the femoral component of the prosthesis. A type 2 plica was a lateral plica extending from the superolateral border of the patella to the infrapatellar fat pad. The type 3 fibrous band reached from the inferior pole of the patella to the intercondylar area. The type 4 nodulus was located at the superior border of the patella, and the type 5 plica was a meniscoid-like tissue between the femoral and the tibial component. Arthroscopic resection resolved the symptoms in 25 of the patients. Different factors seem to contribute to the development of infra-articular plicae after knee alloarthroplasty.