Anterior cruciate reconstruction combined with autologous osteochondral transplantation

The purpose of this prospective study was to evaluate the results of simultaneous anterior cruciate ligament (ACL) reconstruction and osteochondral autograft transplantation performed in patients suffering an anterior instability associated with symptomatic full-thickness cartilage defects. Our clinical report includes the first 21 patients (six women, 15 men) who have been followed up for 32 months or longer. The average patient age was 29 years (range 22–44 years), and mean time from injury to the combined reconstructive surgery was 10 months (range 4–27 months). The cartilage defects had a mean area of 3.5 cm² (range 2.0–5.0 cm²). All patients were evaluated according to the IKDC, Lysholm and Tegner scoring scales by an independent observer. A visual analogue scale (VAS) reflecting patient pain was evaluated. Assessment using the IKDC knee scoring scale revealed 81% of the patients with a normal or nearly normal knee joint. There was a significant improvement in subjective discomfort, and the KT-1000 arthrometric evaluation showed a reduction of the ventral tibial translation (5.9 to 1.9 mm). All but two patients had returned to full activities without restriction and were asymptomatic. The results of this study suggest that symptomatic full-thickness articular cartilage defects associated with ACL instability can be effectively treated by performing ACL reconstruction and osteochondral autologous grafts in one procedure. However, only the years which follow will show the long-term outcome of the patients.     

Is there an option for harvesting autologous osteochondral grafts without damaging weight-bearing areas in the knee joint?

Within the past few years autologous osteochondral transplantation has become an established standardized procedure in joint surgery. One significant disadvantage of this technique is the harvesting of the osteochondral grafts from the weight-bearing area of the knee joint. The tibiofibular articulation is located close to the knee joint that is operated on. This articulation is covered with cartilage. The purpose of this study was to evaluate whether this joint is suitable as a donor site for osteochondral grafts. Ten human knee specimens were freed of all soft tissues around the proximal calf. The age of the specimens ranged between 58 and 79 years. Next the tibiofibular articulation was identified, and both the ligaments and the capsule were removed. After opening the joint the tibial- and fibular-sided joint surfaces were inspected and measured. In all specimens the articular surfaces showed good cartilage coverage. In only a single joint did the cartilage macroscopically show degeneration. In all other joints the cartilage surface was in surprisingly good condition, especially considering the age of the specimens. The average diameter of the cartilage surface on the tibial side was 1.7 ± 0.26 × 1.9 ± 0.22 cm and on the fibular side 1.6 ± 0.31 × 1.8 ± 0.32 cm. This results in an area of cartilage for transplantation of 3.23 cm² at the tibia and of 2.88 cm² at the fibula. The total area for cartilage transplantation is 6.11 cm². The tibiofibular joint contains cartilage, which may be a reasonable donor site even for the elderly patient. Harvesting the graft from this area may avoid iatrogenic damaging of intra-articular weight-bearing cartilage of the knee joint. Received: 9 December 1999 Accepted: 15 March 2000     

Treatment of deep cartilage defects of the patella with periosteal transplantation

Twenty-six consecutive patients (19 men and 7 women) with a mean age of 31.5 years (range 19–52 years) who suffered from an isolated full-thickness cartilage defect of the patella (area ranged from 0.75 to 20.0 cm²) and disabling knee pain were treated with autologous periosteal transplantation (without any chondrocytes). The duration of symptoms was 59 months (range 11–144 months). During the first 5 postoperative days all patients were treated with continuous passive motion (CPM). This was followed by active motion, slowly progressive strength training, and slowly progressive weight-bearing. After a mean follow-up of 42 months (range 24–76 months), 17 patients (65%) were graded as excellent (were painfree), 8 patients (31%) as good (had pain with strenous knee-loading activities), and 1 patient as poor (had pain at rest). Twenty-two patients (85%) had returned to their previous occupation. Twelve patients (46%) had resumed sports or recreational activities at their former level. Repeated magnetic resonance imaging (MRI) investigations showed progressive, and finally complete, filling of the articular defects. Biopsies taken in five randomly selected cases showed hyaline-like cartilage. Patients with full-thickness cartilage defects of the patella and disabling knee pain can be treated with autologous periosteal transplantation (without any chondrocytes), followed by CPM, and slowly progressive strength training and weight-bearing. We believe this is a good method to accomplish regeneration of articular cartilage and satisfactory clinical results. Received: 25 March 1998 Accepted: 14 April 1998     

异种异体和同种异体半月板移植修复兔膝关节半月板缺失的预后研究

目的:研究同种异体半月板和异种异体半月板移植后,移植物在关节内的转归和移植物对关节软骨的保护作用.方法:切除30只成年新西兰白兔的内侧半月板造成内侧半月板缺失的模型,并将新西兰兔分为A组和B组.A组进行同种异体内侧半月板移植.B组从猪半月板取小块半月板组织,修剪成同兔内侧半月板形态和尺寸相同的异种异体半月板植入物,进行兔内侧半月板的异种异体移植.在术后第6周、第12周、第24周时宰杀动物,观察移植半月板、内侧胫骨平台软骨、股骨内髁负重区软骨和股骨滑车软骨的大体形态学改变和组织病理学改变.结果:同种异体半月板移植后,半月板在关节内的形态良好,与关节囊周围愈合良好,移植24周后,可见关节软骨损伤不明显.异种异体半月板移植后短期半月板和关节软骨情况良好,24周后移植物部分被吸收,关节软骨也出现退变和损伤.结论:用猪的半月板组织塑形后移植替代兔内侧半月板组织,术后24周移植物被溶解吸收,并开始出现关节软骨退变.同种异体内侧半月板移植后,半月板的结构和功能重建良好,而且对关节软骨起到了良好的保护作用.     

半月板撕裂与股骨髁半月板区关节软骨损伤的关系（附271例半月板手术治疗病例分析）

通过对近４年来收治的２７１例半月板损伤手术治疗病人的总结分析，对半月板损伤后与股骨髁半月板区关节软骨损伤的关系及是否应早期手术切除半月板进行了讨论，并对本组病例的病程、年龄、不同人群及半月板单纯损伤和合并伤与股骨髁半月板区软骨损伤的情况进行了对比。结果发现：同时发生股骨髁半月板区关节软骨损伤的共７２例，占２６．５７％；股骨髁半月板区关节软骨损伤及程度与半月板损伤后病程的长短有明显关系，而与年龄无关。作者认为：半月板损伤后经过一段时间（运动员在半年以内，普通人不超过２年）的保守治疗，仍有明显症状者，应及时手术切除半月板。     

正常膝关节半月板及关节软骨的低磁场MRI表现

目的:研究正常膝关节半月板及关节软骨的低场MRI表现。材料和方法:选择膝关节无外伤史、无任何临床症状的志愿者28例,按照不同的年龄分为3组。MRI显示正常半月板及关节软骨的外形、信号强度。冠状位T1WI,最厚层面,测量半月板体部厚度;矢状位T1WI,最厚层面,测量半月板前、后角及关节软骨厚度。结果:MRI显示半月板外形均为三角形,厚度随年龄和位置的不同有差异,半月板SET1WI均见不到达关节面的条状高信号。关节软骨的厚度随年龄发生变化,但信号均匀,边缘光整。结论:正常膝关节半月板及关节软骨的厚度随年龄而发生变化,低场MRI半月板内可见线条状高信号,应避免对半月板损伤的误诊。     

异种异体和同种异体半月板移植术后兔半月板和关节软骨中Ⅰ、Ⅱ、Ⅲ、Ⅹ型胶原表达和免疫排斥研究

目的 :研究同种异体半月板移植和异种异体半月板移植后 ,移植半月板和关节软骨中的Ⅰ、Ⅱ、Ⅲ、Ⅹ型胶原表达和免疫排斥反应发生的情况。方法 :切除 30只成年新西兰白兔的内侧半月板造成半月板缺失的动物模型。A组进行同种异体内侧半月板移植。B组取猪半月板组织修剪成同兔内侧半月板形态和尺寸相同的异种异体半月板植入物 ,进行兔内侧半月板的异种异体移植。分别在术后第 6周、12周、2 4周取实验动物的半月板、关节软骨进行Ⅰ、Ⅱ、Ⅲ、Ⅹ型胶原的单克隆抗体的免疫组织化学染色 ,并取外周血进行补体依赖性微量淋巴细胞毒实验 (CDMT) ,用放射免疫法检测血清中IL - 2和IL - 6的含量 ,了解是否发生免疫排斥反应。结果 :同种异体半月板移植后 ,关节软骨和移植半月板的情况良好 ,但术后第 2 4周 ,异种异体移植物部分被吸收 ,关节软骨出现损伤。两组中各时段移植半月板中的Ⅰ、Ⅱ和Ⅲ型胶原的表达情况无明显差异 ,术后第 12周 ,两组关节软骨中Ⅰ、Ⅱ和Ⅲ型胶原的表达情况相似 ,但术后第 2 4周 ,异种异体半月板组的关节软骨开始有异常Ⅹ型胶原表达。同种异体和异种异体半月板移植组均未发现致命的免疫排斥反应发生。结论 :用猪的半月板组织塑形后移植替代兔内侧半月板组织 ,半年后移植物被溶解吸收 ,同种异体?     

Long-term outcome for large meniscal defects treated with small intestinal submucosa in a dog model

BACKGROUND: Large meniscal defects are a common problem for which current treatment options are limited. HYPOTHESIS: Treatment of posterior medial meniscal defects in dogs with small intestinal submucosa is superior to partial meniscectomy in terms of clinical limb function, chondroprotection, and amount and type of new tissue in the defect. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 51 mongrel dogs underwent medial arthrotomy with creation of standardized meniscal defects. The dogs were divided into groups based on defect treatment: small intestinal submucosa meniscal implant (n = 29) or meniscectomy (n = 22). The dogs were assessed for lameness by subjective scoring after surgery and sacrificed at 3, 6, or 12 months and assessed for articular cartilage damage, gross and histologic appearance of the operated meniscus, amount of new tissue in the defect, equilibrium compressive modulus of meniscal tissue, and relative compressive stiffness of articular cartilage. RESULTS: Dogs in the meniscectomy groups were significantly (P < .001) more lame than dogs treated with small intestinal submucosa. Joints treated with small intestinal submucosa had significantly (P <.001) less articular cartilage damage, based on india ink staining, than did those treated with meniscectomy. Menisci receiving small intestinal submucosa had more tissue filling in the defects than did menisci receiving no implants, and this new tissue was more mature and meniscus-like and better integrated with remaining meniscus. CONCLUSION: Small intestinal submucosa scaffolds placed in large meniscal defects resulted in production of meniscus-like replacement tissue, which was consistently superior to meniscectomy in amount, type, and integration of new tissue; chondroprotection; and limb function in the long term. CLINICAL RELEVANCE: Small intestinal submucosa implants might be useful for treatment of large posterior vascular meniscal defects in humans.     

Twenty-year results of combined meniscal allograft transplantation,anterior cruciate ligament reconstruction and advancement of the medial collateral ligament

The purpose of this study was to determine the objective and subjective long-term outcomes of the first free meniscal allograft transplantations in five patients with complete absence or non-repairable lesion of the medial meniscus after 20 years. Between 1984 and 1986 five patients underwent concomitant medial meniscal transplantation with a deep frozen meniscal allograft, ACL reconstruction and femoral advancement or temporary detachment of the MCL. The clinical outcome of the patients was evaluated 20 years postoperatively using clinical assessment, Lysholm-score, KOOS, IKDC-score, radiographs and magnetic resonance imaging. The Lysholm-score ranged between 21 and 97 points of 100 maximal available points. Corresponding to this the total KOOS ranged between 28.4 and 91.1%. The results of the IKDC-score were evaluated as nearly normal (B) (n = 2), abnormal (C) (n = 2) and severely abnormal (D) (n = 1). The radiological evaluation according to the Kellgren-Lawrence classification showed an increase of the degenerative changes between one and four grades. The radiological results revealed clear degenerative changes with long-term follow-up after meniscal allograft transplantation even though some patients did relatively well regarding the subjective and clinical results in the 20-year follow-up examination in comparison with the literature. Despite these relative clear results the question if medial meniscal transplantation can protect against development of arthritis cannot definitely be answered because in this first case series some aspects of meniscus transplantation that have not been considered which turned out to be of importance during the last 20 years. Furthermore, it has to be taken into account that all patients revealed a cartilage damage at the time of surgery and an ACL reconstruction was performed in addition. Nevertheless from biomechanical point of view it might be taken into consideration to combine the medial meniscus transplantation at least with a high tibial osteotomy. Level of evidence was (IV, case series).     

Meniscal allografts--where do we stand?

Meniscal transplantation has been recommended for selected meniscus-deficient patients in an effort to forestall progressive joint degeneration. Meniscal allograft transplantation may be considered for patients with symptoms (pain and swelling) due to meniscal deficiency in an effort to prevent progressive articular cartilage degeneration. Medial meniscal transplantation may also be considered during concomitant anterior cruciate ligament reconstruction, since absence of the medial meniscus results in increased forces in the anterior cruciate ligament graft. Contraindications for meniscal transplantation include advanced articular cartilage degeneration (especially on the flexion weightbearing zone of the condyle), axial malalignment, and flattening of the femoral condyle. Patient evaluation should include standing, long-leg radiographs for assessment of the mechanical axis and magnetic resonance imaging with appropriate pulse sequences for evaluation of hyaline cartilage thickness. Fresh-frozen and cryopreserved allografts are currently the most commonly used transplantation materials. Appropriate graft sizing is critical; most tissue banks size the meniscus based on radiographic tibial plateau measurements. Early results of meniscal transplantation indicate predictable improvements in pain, swelling, and knee function; however, no long-term results are available. Poor results have been reported in patients with advanced cartilage degeneration. Objective evaluations often demonstrate some degree of degeneration of the posterior horn of the transplant. Earlier transplantation should be considered for patients with known meniscal deficiency.     

Combined meniscal allografttransplantation and autologous chiondrocyte implantation

The knee, with complex injury involving the meniscus and articular cartilage, presents a challenging situation forboth physician and patient. The utilization of meniscal transplantation for replacement of the meniscus deficiency has been used successfully. Autologous chondrocyte implantation (ACI) has been utilized to successfully treat the presence of chondral defects in the knee joint. By combining these two procedures the knee homeostasis can be replaced and the knee salvaged, retarding the future growth of degeneration. Initial results appear to be promising, although long-term follow-up will be critical to evaluate.     

Arthroscopic osteochondral autograft transplantation in anterior cruciate ligament reconstruction: A preliminary clinical study

The high incidence of chondral defects of the femoral condyles associated with chronic ACL tears is widely recognised. However, treatment is difficult and controversial. This preliminary report presents our experience with arthroscopic osteochondral autograft transplantation in ACL-deficient knees. The series consists of 12 cases of arthroscopic osteochondral autograft transplantation in conjunction with ACL reconstruction using bone-patellar tendon-bone autograft; eight procedures were primary, and four were revisions of failed synthetic grafts. The patients' ages ranged from 22 to 42 years. There were ten male and two female patients. Chondral lesions in this series ranged from 10 to 22 mm in diameter. Donor site was selected prior to notchplasty, and three to five osteochondral cylinders, 5–10 mm in diameter, 10–15 mm long, were harvested. Improved surgical technique, tubular cutting instruments enabling minimal damage to harvested articular cartilage, and press-fit insertion yielded promising uniform results in ten of 12 cases with 2 years' follow-up. This study addresses the important issue of articular cartilage defects in ACL-deficient knees and possible prevention of premature joint degeneration. The aim of arthroscopic osteochondral autograft transplantation is to slow down the development of osteoarthrosis.     

Autologous chondrocyte implantation in the knee using fibrin

Autologous chondrocyte implantation (ACI) is widely used to treat symptomatic articular cartilage injury of the knee. Fibrin ACI is a new tissue-engineering technique for the treatment of full-thickness articular cartilage defects, in which autologous chondrocytes are inserted into a three-dimensional scaffold provided by fibrin gel. The objective of this study is to document and compare mean changes in overall clinical scores at both baseline and follow-up. Fibrin ACI was used to treat deep cartilage defects of the femoral condyle in 30 patients. There were 24 men and 6 women with a median age of 35 years (range 15–55) and with a mean defect size of 5.8 cm² (range 2.3–12). Clinical and functional knee evaluations were performed using different scoring systems, MRI was performed 24 months postoperatively, and arthroscopy was performed 12 months postoperatively. All patients achieved clinical and functional status improvements following surgery (P < 0.01). The mean scores of the Henderson classification (MRI evaluation) significantly improved from 14.4 to 7 (P = 0.001), and no graft-associated complications were noted. Arthroscopic assessments performed 12 months postoperatively produced nearly normal (grade II) International Cartilage Repair Society scores in 8 of the 10 study patients. Fibrin ACI offers the advantages of technical simplicity, minimal invasiveness, a short surgery time, and easier access to difficult sites than classical ACI. Based on the findings of this clinical pilot study, we conclude that fibrin ACI offers a reliable means of treating articular cartilage defects of the knee.     

Autologous osteochondral grafts in the treatment of cartilage defects of the knee joint

Autologous osteochondral grafting (mosaicplasty) was performed on 18 patients with grade IV cartilage defects of the knee joint. The average age of these 12 men and 6 women was 36 years, follow-up time was 27.2 months and defect size was 252 mm² (18×14 mm). After plain anteroposterior and lateral radiographs and MRI (STIR sequence) examination, diagnostic arthroscopy was performed, followed by autologous osteochondral grafting, avoidance of weight bearing for 6–8 weeks, physiotherapy and continuous passive motion. All patients showed, radiologically (MRI), a full coverage of the defect with articular surface congruity postoperatively. The postoperative ICRS score was normal for 12 and nearly normal for 6 patients. Seven patients showed early persistent joint effusion for an average of 5.3 months. Hyaline-like cartilage coverage was found in four patients on second-look arthroscopy. The transplantation of autologous osteochondral grafts is being applied in an effort to reconstruct the affected articular surface with properties similar to those of hyaline cartilage. This method retains the integrity and function of a damaged joint, providing promising results in terms of preventing the development of early arthritis in young patients.     

Articular cartilage injury of the posterior lateral tibial plateau associated with acute anterior cruciate ligament injury

Thirty-nine knees in 39 patients with recent anterior cruciate ligament (ACL) rupture (age 14–55 years; with a mean age of 22.8 years) were selected from our cases of ACL reconstruction from July 2005 to June 2006, to take part in a study on articular cartilage injury of the posterior lateral tibial plateau associated with acute ACL injury and on the correlation between bone bruises depicted on MRI and cartilage injury of the posterior lateral tibial plateau detected at arthroscopic ACL reconstruction. Using preoperative MRI, we evaluated whether there were bone bruises or not in the lateral compartment of the knee and divided them accordingly into two groups: the bone bruise positive group and the negative group. The differences in the proportions of the lateral meniscus (LM) tears and the cartilage injuries in the two groups were evaluated using Fisher’s exact probability test. Thirty-five cases out of 39 arthroscopic ACL reconstructions (89.7%) were regarded as bone bruise positive in the lateral compartment and four cases (10.3%) were regarded as negative. At arthroscopic ACL reconstruction, 33 cases (84.6%) had tears in the LM posterior horn, 34 cases (87.2%) had articular cartilage injuries in the lateral femoral condyle and 29 cases (74.3%) had articular cartilage injuries in the posterior lateral tibial plateau. From 35 bone bruise positive cases, 32 cases (91.4%) had tears in the LM posterior horn, 33 cases (94.3%) had articular cartilage injuries in the lateral femoral condyle and 28 cases (80%) had articular cartilage injuries in the posterior lateral tibial plateau. Of four bone bruise negative cases, one case (25%) had a tear in the LM posterior horn, articular cartilage injury of the lateral femoral condyle and of the posterior lateral tibial plateau. There was a statistically significant correlation between the proportion of bone bruise and cartilage injury of the lateral femoral condyle (P = 0.004), that of the posterior lateral tibial plateau (P = 0.04) and that of tears in the LM posterior horn (P = 0.008). This current study has demonstrated that we need to pay attention to cartilage damage of the posterior lateral tibial plateau as well as to posterior horn tears in LM, when acute ACL injury is shown. We also have to ensure that we follow the long-term progress of cartilage injuries, with the aim of preventing these injuries becoming osteoarthritis after ACL reconstruction.     

不同细胞移植修复兔全层关节软骨缺损的比较研究

目的 :比较软骨细胞、骨髓基质细胞及成纤维细胞对全层关节软骨缺损的修复作用。材料和方法 :取幼兔的软骨细胞、骨髓基质细胞及成纤维细胞 ,共 3种有生成软骨潜力的细胞进行体外分离培养 ;以聚乳酸 (PLA)为载体 ,将培养的原代细胞植入PLA支架上 ,形成细胞 -PLA复合物。于 2 8只成年新西兰大白兔的股骨滑车关节面上造成直径 4 5mm、深 3 0mm的全层关节软骨缺损 ,将 3种细胞 -PLA复合物分别植入关节软骨缺损处。植入细胞 -PLA复合物为实验组 ,单纯植入PLA支架为对照组。术后 6周、12周观察缺损修复情况及新生组织类型。结果 :软骨细胞移植组为软骨样组织修复 ,分界明显 ,甲苯胺兰及Ⅱ型胶原染色阳性 ;软骨下骨部分重建 ;细胞排列紊乱。骨髓基质细胞移植组为软骨样组织修复 ,分界不明显 ,甲苯胺兰及Ⅱ型胶原染色阳性 ;软骨下骨重建良好 ,软骨下潮线恢复 ;细胞排列趋于正常。成纤维细胞移植组为纤维组织修复 ,甲苯胺兰及Ⅱ型胶原染色阴性 ;软骨下潮线消失。对照组为纤维组织修复。结论 :软骨细胞、骨髓基质细胞移植修复软骨缺损明显优于成纤维细胞及对照组。骨髓基质细胞与软骨细胞移植组的修复结果无统计学差异 ,但骨髓基质细胞修复组织的细胞排列有序 ,软骨下骨重建良好 ,与周围组织融合密切 ,更接近正?     

Osteochondral autologous transplantation versus microfracture for the treatment of articular cartilage defects in the knee joint in athletes

The purpose of this prospective randomized clinical study was to compare the outcomes of mosaic type autologous osteochondral transplantation (OAT) and microfracture (MF) procedures for the treatment of the articular cartilage defects of the knee joint in athletes. Between 1998 and 2002, a total of 57 athletes with a mean age of 24.3 years and with a symptomatic lesion of the articular cartilage in the knee were randomized to undergo either OAT or MF procedure. There were 28 athletes in OAT group and 29 in MF group. Patients were evaluated using a modified Hospital for Special Surgery (HSS) and International Cartilage Repair Society (ICRS) scores, MRI and clinical assessment after 6, 12, 24 and 36 months after the surgery. According to the modified HSS and ICRS scores, functional and objective assessment showed that 96% had excellent or good results after OAT compared with 52% after MF procedure (P<0.001). In 12, 24 and 36 months after the operations, the HSS and ICRS showed statistically significantly better results in the OAT group (P=0.03; P=0.006; P=0.006). Twenty-six (93%) athletes following OAT and fifteen (52%) athletes following MF returned to sports activities at the preinjury level at an average of 6.5 months (range, 4–8 months) after the operations. At an average of 37.1 months follow-up, our prospective, randomized, clinical study in athletes has shown significant superiority of the OAT over MF for the repair of articular cartilage defects in the knee.     

Subchondral bone marrow edema in patients with degeneration of the articular cartilage of the knee joint

PURPOSE: To retrospectively determine at magnetic resonance (MR) imaging the prevalence of subchondral bone marrow edema beneath arthroscopically proved articular cartilage defects. MATERIALS AND METHODS: The study was performed in compliance with HIPAA regulations, and a waiver of informed consent was obtained from the institutional review board before the study was performed. The study consisted of 132 patients (70 men, 62 women; average age, 53 years) with articular cartilage defects of the knee joint who underwent MR imaging of the knee and subsequent arthroscopic knee surgery. At the time of arthroscopy, each articular cartilage lesion was graded by using the Noyes classification system. MR examinations were retrospectively reviewed to determine the size, depth, and location of subchondral bone marrow edema without knowledge of the arthroscopic findings. Pairwise Fisher exact tests and two-sample t tests were used to correlate MR imaging findings of subchondral bone marrow edema with the arthroscopic grade of articular cartilage degeneration. RESULTS: Subchondral bone marrow edema was seen beneath 105 (19%) of 554 articular cartilage defects identified at arthroscopy. It was not observed beneath any of the six grade 1 cartilage defects but was observed beneath eight (4.9%) of 163 grade 2A defects, 40 (14.4%) of 278 grade 2B defects, 54 (55.1%) of 98 grade 3A defects, and three (33.3%) of nine grade 3B defects. Subchondral bone marrow edema was also seen beneath four (1.4%) of 238 articular surfaces that appeared normal at arthroscopy. The mean depth and cross-sectional area of subchondral bone marrow edema increased with increasing grade of the articular cartilage lesion. CONCLUSION: Higher grades of articular cartilage defects are associated with higher prevalence and greater depth and cross-sectional area of subchondral bone marrow edema.     

Mid-term results of Autologous Matrix-Induced Chondrogenesis for treatment of focal cartilage defects in the knee

Articular cartilage defects heal poorly. Autologous Matrix-Induced Chondrogenesis (AMIC) is an innovative treatment for localized full-thickness cartilage defects combining the well-known microfracturing with collagen scaffold and fibrin glue. The purpose of this prospective study was to evaluate the medium-term results of this enhanced microfracture technique for the treatment of chondral lesions of the knee. Thirty-two chondral lesions in 27 patients were treated with AMIC. Within the context of clinical follow-up, these patients were evaluated for up to 5 years after the intervention. Five different scores (Meyer score, Tegner score, Lysholm score, ICRS score, Cincinatti score) as well as radiographs were used for outcome analysis. Articular resurfacing was assessed by magnetic resonance imaging (MRI). The average age of patients (11 females, 16 males; mean body mass index 26, range 20–32) was 37 years (range 16–50 years). The mean defect size of the chondral lesions was 4.2 cm² (range 1.3–8.8 cm²). All defects were classified as grade IV according to the Outerbridge classification. The follow-up period was between 24 and 62 months with a mean of 37 months. Twenty out of 23 individuals (87%) questioned were subjectively highly satisfied with the results after surgery. Significant improvement (P < 0.05) of all scores was observed as early as 12 months after AMIC, and further increased values were notable up to 24 months postoperatively. MRI analysis showed moderate to complete filling with a normal to incidentally hyperintense signal in most cases. Results did not show a clinical impact of patient’s age at the time of operation, body mass index and number of previous operations (n.s.). In contrast, males showed significant higher values in the ICRS score compared to their female counterparts. AMIC is an effective and safe method of treating symptomatic full-thickness chondral defects of the knee in appropriately selected cases. However, further studies with long-term follow-up are needed to determine whether the grafted area will maintain structural and functional integrity over time.     

Silicone rubber: an alternative for repair of articular cartilage defects

Silicone-rubber implants were used to fill full-thickness articular cartilage in the trochlea area of the knee joint in rabbits, for the purpose of studying the long-term influence of silicone-rubber implant on surrounding articular cartilage. Forty eight weeks after surgery, the silicone rubbers were still fitted tightly into the defects; surrounding cartilage showed mild degeneration, better than the control group. Our results showed silicone-rubber implantation for repairing local articular cartilage defects can effectively delay the pathogenetic progression of osteoarthritis.