Soft tissue coverage options around the knee.

Defects around the knee exhibit various etiologies and pose challenges to both orthopedists and plastic surgeons. While a number of reconstructive coverage options are available, flaps are almost always required for complex defects. Many local flaps are easily placed, including muscle and perforator flaps sourced from the thigh to the leg. As the recipient vessels lie deep, free tissue transfers are challenging. Good postoperative management and efficient collaboration between orthopedic and reconstructive surgeons are the keys to successful knee reconstruction, restoring an esthetic contour and preserving joint function.

Radiographic outcomes in the coronal plane with iASSIST™ versus optical navigation for total knee arthroplasty: A preliminary case-control study.

BACKGROUND: The new navigation system iASSIST™ for total knee arthroplasty (TKA) relies on accelerometers and gyroscopes. The objective of this prospective study was to compare the accuracy of iASSIST™ to that of the conventional optical navigation system Navitrack™ by determining the rate of mechanical axis restoration (±3°), postoperative mean mechanical alignment, rate of adequate femoral and tibial component positioning, mean operative time, and occurrence of navigation-related adverse events. HYPOTHESIS: The rate of mechanical axis restoration (±3°) is not lower with iASSIST™ than with the conventional navigation system Navitrack™. MATERIAL AND METHODS: Of 40 patients who underwent primary TKA between October 2013 and March 2014, 20 had navigation using iASSIST™ and 20 using Navitrack™. Six months after TKA, an independent observer measured three parameters on coronal radiographs: the hip-knee-ankle angle (HKA), the mechanical lateral distal femoral angle (mLDFA), and the mechanical medial proximal tibial angle (mMPTA). RESULTS: The two groups showed no significant differences for the rates of HKA restoration (P=0.3), adequate coronal positioning of the femoral component (P=0.12) and tibial component (P=0.12), or optimal success (P=0.09). Significant differences in favour of iASSIST™ were demonstrated for the values and angular deviations of the HKA (P=0.02) and mMPTA (P=0.01), whereas no significant difference was found for mLDFA. There were no significant differences regarding the mean operative time (P=0.06) or the occurrence of navigation-related adverse events (P=0.18). DISCUSSION: The iASSIST™ system provides a neutral mechanical axis and optimal component position in the coronal plane in 95% of cases, indicating that it is as accurate as the optical navigation system Navitrack™. LEVEL OF EVIDENCE: III, prospective case-control study.

Mobile-bearing versus fixed-bearing total knee implants. Results of a series of 100 randomised cases after 9 years follow-up.

HYPOTHESIS: Mobile-bearing total knee arthroplasty (TKA) implants were developed as an alternative to fixed-bearing implants because of their theoretical advantages related to wear and range of motion. For all that, none of the short-term and medium-term studies published so far have reported a significant clinical improvement related to these mobile bearings. The goal of this study was to compare the outcomes of fixed and mobile bearings in the same type of TKA model after a longer follow-up. MATERIAL AND METHODS: This series initially comprised 100 patients with a mean age of 73 years who were operated by a single surgeon. The patients were randomised to receive either a fixed bearing TKA implant or a mobile one; their outcomes evaluated after a mean of 9 years (7.2-12.2) follow-up. Twenty-two patients died before the final review, 15 were lost to follow-up and 2 were excluded. This resulted in 30 patients with a mobile-bearing knee and 31 with a fixed-bearing knee being available for analysis. RESULTS: There were no significant clinical differences between the groups receiving a fixed or mobile bearing in terms of the range of motion, subjective outcomes or validated outcomes measured, such as the self-reported Oxford or the IKS. Conversely, there was a significantly higher rate of osteolysis in the fixed-bearing group, but it was not clinically relevant. CONCLUSION: This study, which has the longest published follow-up, confirms the results found in the seven randomised studies published up to now: there are no significant differences in the clinical outcomes between fixed-bearing and mobile-bearing inserts of the same TKA model. Although the mobile bearing knees had a better radiographic appearance, this did not translate to better clinical outcomes. In practice, the superiority of mobile bearings is solely theoretical. LEVEL OF EVIDENCE II: Prospective randomised study.

Actifit synthetic meniscal substitute: experience with 18 patients in Brest, France.

BACKGROUND: The management of post-meniscectomy pain is poorly standardised. Allogeneic transplantation may be appropriate in some patients after total meniscectomy. After partial meniscectomy, the synthetic meniscal substitute Actifit may constitute a valid option if the knee is stable or stabilised and aligned or re-aligned. The interconnected pore structure of Actifit promotes tissue regeneration from the meniscal wall. Arthroscopy is used to position the implant, which is then sutured to the remaining native meniscus using horizontal stitches and to the meniscal wall using vertical stitches. However, a burdensome programme of rigorous rehabilitation is required after Actifit implantation. HYPOTHESIS: We hypothesised that implantation of a meniscal substitute effectively alleviated pain without adversely affecting the knee. OBJECTIVES: To assess the intra-articular behaviour of Actifit and the outcomes of Actifit implantation in a prospective case-series of patients monitored using arthroscopy, pathology, and imaging studies, as well as the Lysholm score to assess clinical benefits on daily activities. MATERIALS AND METHODS: Between October 2009 and April 2012, 18 patients underwent Actifit implantation at the military hospital in Brest, France. All procedures were performed by the same surgeon, who had extensive experience with meniscal suturing. There were 13 males and 5 females aged 20 to 46 years. The medial meniscus was involved in 13 patients and the lateral meniscus in 5 patients. Actifit implantation was used alone in 6 patients and in combination with anterior cruciate ligament reconstruction and/or realignment osteotomy in 12 patients. All patients were followed-up for at least 2 years. RESULTS: The mean Lysholm score after 1 year was 92%, indicating excellent outcomes. Magnetic resonance imaging showed no damage to the implant or degeneration of the neighbouring cartilage. Histological examination of meniscal substitute biopsies taken 1 year after implantation showed polymer ingrowth by normal chondrocytes and fibrochondrocytes. The clinical and radiographic outcomes compared favourably with those seen after isolated procedures on bone or ligaments. DISCUSSION: Actifit has no deleterious effects on patients. The implant induces and promotes meniscal regeneration. Actifit constitutes a major addition to our therapeutic armamentarium. We provide convincing evidence that meniscal reconstruction can be highly beneficial in decreasing the risk of progression to knee osteoarthritis. LEVEL OF EVIDENCE: IV.

Mosaic osteochondral transplantations in the knee joint, midterm results of the SFA multicenter study.

INTRODUCTION: There are several possible options to treat focal articular cartilage defects of the knee. The aim of this study was to evaluate the results and prognostic factors cartilage defects of the knee treated by autologous osteochondral mosaicplasty after more than five years of follow-up. PATIENTS AND METHODS: One hundred forty-two cases were included in this retrospective multicenter study. Etiologies included osteochondral fractures (n=79), and osteochondritis dissecans (n=61). Mean age of patients was 31. There was a majority of men (76%). Mean BMI was 25 (range: 21-41). Fifty-three percent of the knees had a history of surgery. Mean delay between the accident and surgery was 2.5 years. Mean area of the defect was 2.29 cm(2) (range: 0.3-12.25 cm(2)). The depth of the defect was 3 or 4 on the ICRS score in 97% of cases. An additional surgical procedure was associated with mosaicplasty in 14% of the cases. The follow-up evaluation was based on the Hughston score, the ICRS score, the IKDC subjective score, and the IKDC radiological score. Evaluation of control MRI was based on a modified MOCART score. RESULTS: The mean follow-up was 96 ± 28 months. There were complications in 19 patients. Patients were able to begin athletic activities again after a mean 35 weeks. Most patients (81.8%) were satisfied or very satisfied. There was a significant improvement (p<0.001) in the ICRS, IKDC function and Hughston scores at follow-up. The factors for a good prognosis were: male gender, medial femoral condyle defects, osteochondritis dissecans, deep, small defects, and the shortest possible delay to surgery. Obesity, smoking, work-related accidents, the level of sports practiced, the percentage of coverage of the defect, the number of plugs, and associated lesions did not have a statistically significant effect on the functional results in the final follow-up. DISCUSSION: Autologous osteochondral mosaicplasty seems to be a reliable technique in the short and intermediate term. It has the advantage of being less expensive than reconstructive techniques, is a one-step surgical procedure and results in immediate restoration of cartilage surface. Nevertheless, this is a difficult technique, which may result in complications and requires articular harvesting. This technique is limited by the size of the defect to be treated. The primary indication is deep, small defects on the medial femoral condyle.

Treatment of knee cartilage defect in 2010.

Treatment of knee cartilage defect, a true challenge, should not only reconstruct hyaline cartilage on a long-term basis, but also be able to prevent osteoarthritis. Osteochondral knee lesions occur in either traumatic lesions or in osteochondritis dissecans (OCD). These lesions can involve all the articular surfaces of the knee in its three compartments. In principle, this review article covers symptomatic ICRS grade C or D lesions, depth III and IV, excluding management of superficial lesions, asymptomatic lesions that are often discovered unexpectedly, and kissing lesions, which arise prior to or during osteoarthritis. For clarity sake, the international classifications used are reviewed, for both functional assessment (ICRS and functional IKDC for osteochondral fractures, Hughston for osteochondritis) and morphological lesion evaluations (the ICRS macroscopic evaluation for fractures, the Bedouelle or SOFCOT for osteochondritis, and MOCART for MRI). The therapeutic armamentarium to treat these lesions is vast, but accessibility varies greatly depending on the country and the legislation in effect. Many comparative studies have been conducted, but they are rarely of high scientific quality; the center effect is nearly constant because patients are often referred to certain centers for an expert opinion. The indications defined herein use algorithms that take into account the size of the cartilage defect and the patient's functional needs for cases of fracture and the vitality, stability, and size of the fragment for cases of osteochondritis dissecans. Fractures measuring less than 2 cm(2) are treated with either microfracturing or mosaic osteochondral grafting, between 2 and 4 cm(2) with microfractures covered with a membrane or a culture of second- or third-generation chondrocytes, and beyond this size, giant lesions are subject to an exceptional allografting procedure, harvesting from the posterior condyle, or chondrocyte culture on a 3D matrix to restore volume. Cases of stable osteochondritis dissecans with closed articular cartilage can be simply monitored or treated with perforation in cases of questionable vitality. Cases of open joint cartilage are treated with a PLUS fixation if their vitality is preserved; if not, they are treated comparably to osteochondral fractures, with the type of filling depending on the defect size.

Knee osteochondral fractures in skeletally immature patients: French multicenter study.

INTRODUCTION: Femoral or patellar osteochondral fractures complicating patellar dislocation are more frequently observed in adolescents than in adults. These incidental lesions of vulnerable joint cartilage are often neglected in the initial phase, which is regrettable given their good capacity for healing after repositioning. The objective of this study was to investigate the characteristics and analyze the results of repositioning these fractures in skeletally immature patients. MATERIAL AND METHODS: This retrospective multicenter study grouped 14 patients and knees (seven females). The mean age at the time of the accident was 12.9 years (range, 11.2-14.9 years) for the girls and 14 years (range, 12.2-15 years) for the boys. These fractures involved the lateral condyle in nine cases and the patella in five cases. The injury mechanism was secondary to demonstrated patellar dislocation (n=9) or a direct impact (n=4). In nine cases out of 14, a leisure sports accident was the cause. The injury was treated a mean 5.2 days (range, 0-20 days) after the accident. All of the detached fragments were repositioned surgically with screw fixation (n=5), resorbable pins (n=5), or pull-out suture (n=4). Biological glue was added for six patients. Patellar stabilization was associated during the same procedure in two cases. RESULTS: No postoperative complications were observed. The results at the mean follow-up of 30 months (range, 15-89 months) showed no revision for failure, with all of the fractures demonstrating union at the final examination. The mean IKDC 2000 subjective score was 88±6 (range, 79-98) out of 100 points. The subjective satisfaction level was very satisfied in two cases and satisfied in the 12 others. The final IKDC score was A for eight patients, B for five patients, and C for one patient. Three patients underwent secondary patellar stabilization surgery. CONCLUSION: Better knowledge of this fracture and attentive reading of the radiographic images of a knee with hemarthrosis should result in more frequent diagnosis of this condition and adapted treatment. Unexplained hemarthrosis in a context of trochlear dysplasia should be considered to be associated with an OCF until proof of the contrary. A fragment released in a weightbearing zone should ideally be repositioned within 10 days but remains possible at 2 months. It regularly provides bone union and good results in children.

Painful medial knee compartment syndrome in over-45-year-olds. II--technical note: Biomechanical considerations: theoretic analysis of load distribution in the knee according to plane and to gait phase.

Varus deviation as defined by Thomine is the basis for understanding load distribution between the medial and lateral tibial plateau; it was originally defined in the frontal plane. Analysis in the sagittal and horizontal planes leads to a concept of varizing area. Varizing area sheds light on how, during gait, load predominates in the medial and posteromedial knee. It also accounts for the following two findings: (a) degenerative lesions are mainly medial, even when the mid-knee axis is normal; (b) degenerative lesions are mainly posterior.

Painful medial knee compartment syndrome in over-45 year-olds: I--medical or surgical management: a series of 174 patients.

INTRODUCTION: There is at present no consensus on the management of degenerative medial meniscus lesions in patients aged over 45 years without proven osteoarthritis, especially given that the causal relation between degenerative meniscal lesion and osteoarthritis remains controversial. A prospective multicenter non randomized study was therefore performed. The principal objective was to assess surgeons' practice in the management of degenerative medial meniscus lesions. The secondary objectives were to identify predictive and prognostic factors and to compare medical versus surgical attitudes so as to draw up an adapted treatment strategy. PATIENTS AND METHOD: One hundred and seventy-four patients were included between September 2008 and February 2010, and distributed between a surgical (n=104) and a medical group (n=70). Minimum follow-up was 6 months. Patient satisfaction and health-related quality of life on the SF-36 questionnaire were assessed at 6 months. RESULTS: No difference emerged between the surgical and medical groups. However, predictive factors for poor results were identified: overweight (p=0.005), cartilage lesions (p=0.035) and meniscus extrusion (p=0.006). DISCUSSION: Results clarified the relation between degenerative meniscus lesions and osteoarthritis, in terms of meniscal incompetence. Meniscal extrusion should be seen as an arthrogenic degenerative meniscus lesion. We recommend a management strategy based on terrain and imaging data (X-ray and MRI), with the aim of providing patient relief while conserving cartilage.

Evidence of association between GDF5 polymorphisms and congenital dislocation of the hip in a Caucasian population.

OBJECTIVE: Congenital dislocation of the hip (CDH) is a multifactorial disease which involves genetic factors that are still unidentified. Recently, a functional polymorphism (rs143383) of the 5'-untranslated region of GDF5 (Growth/Differentiation Factor 5) - previously reported to be associated with osteoarthritis - has been associated with CDH in a Chinese population. The aim of our study was to determine whether GDF5, known to be involved in bone, joint and cartilage morphogenesis, is also associated with CDH in Caucasians. DESIGN: We genotyped three tagSNPs (rs224334, rs143384, rs143383) in 239 cases and 239 controls from western Brittany (France) where CDH is frequent, and tested the association using both single-locus and haplotype-based approaches. RESULTS: The most significant association was observed with rs143384. The T allele of this SNP was overrepresented in cases (65.9% vs 55.9%, P=0.002). Under a recessive model, carriers of the TT genotype had a 1.71-fold higher risk of developing CDH than carriers of the other genotypes (OR(TT vs CT+CC)=1.71, 95% CI: [1.18-2.48], P=0.005). At a nominal level, the association was also significant with rs143383 (OR(TT vs CT+CC)=1.52, 95% CI: [1.05-2.19], P=0.026). The haplotype carrying the susceptibility alleles of these SNPs was also more frequent in cases (65.9% vs 55.9%, OR=1.53, 95% CI: [1.18-1.98], P=0.002). CONCLUSION: This study reports, for the first time, the association between GDF5 polymorphisms and CDH in Caucasians, and points out another polymorphism of interest that requires further investigation. Reduction in GDF5 expression might lead to developmental deficiency of ligaments and capsule in hip joint, and therefore contribute to CDH pathogenesis.

Common peroneal nerve palsy complicating knee dislocation and bicruciate ligaments tears.

INTRODUCTION: The occurrence rate of common peroneal nerve (CPN) palsy associated with knee dislocation or bicruciate ligament injury ranges from 10 to 40%. The present study sought first to describe the anatomic lesions encountered and their associated prognoses and second to recommend adequate treatment strategy based on a prospective multicenter observational series of knee ligament trauma cases. MATERIAL AND METHODS: Twelve out of 67 knees treated for dislocation or bicruciate lesion presented associated CPN palsy: two females, 10 males; mean age, 32 years. Four sports injuries,three traffic accidents and five other etiologies led to seven complete dislocations and five bicruciate ruptures. Four cases involved associated popliteal artery laceration ischemia; one of the dislocations was open. Paralysis was total in eight cases and partial in four. There were two complete ruptures, three contusions with CPN in continuity stretch lesions and three macroscopically normal aspects. RESULTS: At a minimum 1 year's follow-up, regardless of the initial surgical technique performed,recovery was complete in six cases, partial (in terms of motor function) in one and absent in five. Without specific CPN surgery, spontaneous recovery was partial in one case, complete in two and absent in none. Following simple emergency or secondary neurolysis, remission was total in four cases and absent in one. Three nerve grafts were all associated with non-recovery. DISCUSSION: The present results agree with literature findings. Palsy rates varied with trauma circumstances and departmental recruitment. Neurologic impairment was commensurate to ligamentary damages. The anatomic status of the CPN, subjected to violent traction by dislocation,was the most significant prognostic factor for neurologic recovery. In about 25% of dislocations, contusion-elongation over several centimeters was associated with as poor a prognosis as total rupture. CPN neurolysis is recommended when early clinical and EMG recovery fails to progress and/or in case of lateral ligamentary reconstruction. Possible peripheral nerve impairment needs to be included in the overall functional assessment of treatment for severe ligaments injuries and knee dislocation. LEVEL OF EVIDENCE: Level IV, prospective study.

Do HOXB9 and COL1A1 genes play a role in congenital dislocation of the hip? Study in a Caucasian population.

OBJECTIVE: Congenital dislocation of the hip (CDH), which is one of the most common congenital skeletal disorders, corresponds to an abnormal seating of the femoral head in the acetabulum. It is commonly admitted that CDH presents a genetic component. However, little is known about the genetic factors involved. This study aimed to determine the role of two potential candidate genes on chromosome 17 in CDH: HOXB9 (involved in limb embryonic development) and COL1A1 (involved in joint laxity). METHOD: We set up a case-control association study (239 cases and 239 controls) in western Brittany (France) where CDH is particularly frequent. The set of informative single nucleotide polymorphisms (SNPs) in each gene was selected using Tagger and genotyped using the SNaPshot method (n=2 and n=10, respectively). The association was tested both through single-locus and haplotype-based analyses, using SAS and Haploview softwares. In addition, we carried out the transmission disequilibrium test (TDT) with the same polymorphisms from a sample of 81 trios (i.e., 81 patients included in the case-control study and their both parents). RESULTS: The case-control study revealed no significant association between CDH and the tagSNPs selected in both HOXB9 and COL1A1. Moreover, the TDT did not reveal distortion in allelic and haplotype transmission of the studied markers. CONCLUSION: Our study did not support an association between HOXB9 and COL1A1 and CDH in our population. These negative findings were obtained by population- and family-based designs. Analysis of the genetic component of CDH should focus on other candidate genes.

Osteoarthritis in patients with anterior cruciate ligament rupture: a review of risk factors.

The risk factors for the development of osteoarthritis (OA) in patients who have had an anterior cruciate ligament (ACL) rupture are reviewed. Although the principle arthrogenic factor is the increased anterior tibial displacement that is associated with the rupture, other direct and indirect factors contribute. Meniscal and chondral injuries can be present before, during, and develop after the index injury, making assessment of the relative importance of each difficult. Most studies concentrate on the radiological changes following ACL rupture and reconstruction. However the rate of significant symptomatic OA needing major surgical intervention is lower. This needs to be considered when advising patients on the management of their ruptured ACL. The long-term outcome in patients who are symptomatically stable following an ACL rupture is uncertain, although in a small cohort of elite athletes all had degenerative changes by 35 years and eight out of 19 (42%) had undergone total knee replacement. At 20 years follow-up the reported risk of developing osteoarthritis is lower after ACL reconstruction (14%-26% with a normal medial meniscus, 37% with meniscectomy) to untreated ruptures (60%-100%).

[Septic arthritis after arthroscopic cruciate ligament reconstruction: in vitro comparison of the behavior of two types of interference screws towards the Staphylococcus aureus adherence]. / Arthrite septique après ligamentoplastie du pivot central sous arthroscopie : comparaison in vitro du comportement de deux types de vis d'interférence vis-à-vis de la fixation du Staphylococcus aureus.

PURPOSE OF THE STUDY: We report the results of an experimental study designed to investigate the behaviour of two types of interference screws (bioabsorbable versus titanium) in a context of Staphylococcus aureus infection. The main objective was to study one of the possible sources of failure for the treatment of acute arthritis of the knee after arthroscopic reconstruction of the cruciate ligament. MATERIAL AND METHODS: We used six interference screws made of titanium and six bioabsorbable screws (PLLA-PDLLA). All screws measured 9mmx25mm, were cannulized and sterilized. These screws were submitted to a protocol elaborated in cooperation with the bacteriologists. After contamination with a strain of S. aureus, the screws were washed four times in saline solution to eliminate germs adsorbed in the aqueous phase. The last step was trypsination to detach germs remaining fixed onto the screws and contained in the biofilms of glycocalix. A germ count was made after each step. For each screw, we determined the difference (Delta) corresponding to the number of germs really adherent to the screw. Mann-Whitney analysis was performed. RESULTS: On average, the germ count in the aqueous phase was 0.0855.10(5)/ml for the titanium screw versus 0.223.10(5)/ml for the bioabsorbable screw. The mean count of germs fixed in the biofilm (mean Delta) was 17.695+/-3.88.10(5) for the titanium screw and 45.86+/-3.61.10(5) for the bioabsorbable screw. The difference was statistically significant (p=0.0039). DISCUSSION: Our experimental results support the efficacy of abundant arthroscopic lavage in a context of infection, confirming the results of very recent studies. However, irrespective of the type of material used, bioabsorbable screws are more prone to persistent microbial adherence than titanium screws. It is hypothesized that the hydrophilic, more porous microstructure of bioabsorbable screws favors bacterial adherence. In practice, this implies that arthroscopic washout must be as abundant and as complete as possible, yet may not be sufficient to clean the entire surface of potentially contaminated screw positioned deep in a bony tunnel.

[Tibial valgus osteotomy]. / Ostéotomie tibiale de valgisation.

The tibial valgus osteotomy whatever its technique has a survival rate of about 85 % to 10 years, if we consider the reoperation as a criterion of failure, with a confidence index at 78%. The age, weight, sex and functional signs have no impact on the outcome. We have found no evidence in the preoperative radiographic assessment, neither the medial pinch, or varus epiphyseal neither varisant gap, which could be a failure and a reoperation before the tenth year. Good results were observed significantly when there is an over-valgus at least 3 degrees of global axis of the lower limb. This corresponds to a valgus epiphyseal by more than 2 degrees . The substantial reduction in the gap varisant that lowers the overall time varisant below 200 kg cm provides the same positive results. The outcome will depend directly on the accuracy of the calculation of the preoperative correction performed and the quality of surgical achievement. Because of the need for precision, navigation technique appears as reliable, simple which makes it also possible to monitor the front slope and tibial rotation induced. The osteosynthesis must be stable and rigid to avoid postoperative loss of correction.

Autologous chondrocyte implantation in a novel alginate-agarose hydrogel: outcome at two years.

Autologous chondrocyte implantation is an established method of treatment for symptomatic articular defects of cartilage. CARTIPATCH is a monolayer-expanded cartilage cell product which is combined with a novel hydrogel to improve cell phenotypic stability and ease of surgical handling. Our aim in this prospective, multicentre study on 17 patients was to investigate the clinical, radiological, arthroscopic and histological outcome at a minimum follow-up of two years after the implantation of autologous chondrocytes embedded in a three-dimensional alginate-agarose hydrogel for the treatment of chondral and osteochondral defects. Clinically, all the patients improved significantly. Patients with lesions larger than 3 cm(2) improved significantly more than those with smaller lesions. There was no correlation between the clinical outcome and the body mass index, age, duration of symptoms and location of the defects. The mean arthroscopic International Cartilage Repair Society score was 10 (5 to 12) of a maximum of 12. Predominantly hyaline cartilage was seen in eight of the 13 patients (62%) who had follow-up biopsies. Our findings suggest that autologous chondrocyte implantation in combination with a novel hydrogel results in a significant clinical improvement at follow-up at two years, more so for larger and deeper lesions. The surgical procedure is uncomplicated, and predominantly hyaline cartilage-like repair tissue was observed in eight patients.

[What's new in fundamental research: cartilage]. / Quoi de neuf en recherche fondamental? Le cartilage.

The localized defects of the articular cartilage of the knee are not rare, in particular concerning the femoral condyles. There is practically no potential for spontaneous repair of cartilage defects reaching the sub-chondral bone and any destruction of the articular cartilage, independently of its origin, is final. This destruction has significant consequences. Currently used techniques, such as Pridie perforation or mosaicplasty have demonstrated effectiveness, but also their limitations. Implantation of autologous chondrocytes constitutes the main alternative to current therapeutic approaches. Nevertheless, many problem persist and have led to research and development of a validated technique for autologous chondrocyte implantation using a biomaterial support. Chondrocyte transplantation on solid support is currently under study.

[Chronic instability in the ankle area]. / Instabilité chronique autour de la cheville.

For ankle sprains, the initial radiological work-up must include weight-bearing AP and lateral stress views of the sprained and healthy ankle. Films are taken in auto-varus. Other explorations included arthroMRI, arthroscanner or MRI which can be indicated preoperatively to confirm suspected cartilage injury or an associated ligament tear. These techniques should be employed when pertinent information can be expected according to the clinical situation and the operator's experience. In the emergency setting, ultrasonography can provide a simple low-cost confirmation of joint hematoma which is more precise than x-rays with a positive predictive value of nearly 100%. The objective and subjective clinical outcome after surgical anatomic repair or ligamentoplasty are quite similar. The two principal differences relate to persistent subjective instability and post-operative surgical complications. Thus there are advantages and disadvantages for each option advantage for anatomical repair because of the low rate of surgical complications and advantage for ligament repairs which stabilize the subtalar joint with a low rate of residual instability.