Objectives. Articular cartilage damage is a primary outcome of pre-clinical and clinical studies evaluating meniscal and cartilage repair or replacement techniques. Recent studies have quantitatively characterized India Ink stained cartilage damage through light reflectance and the application of local or global thresholds. We develop a method for the quantitative characterisation of inked cartilage damage with improved generalisation capability, and compare its performance to the threshold-based baseline approach against gold standard labels. Methods. The Trainable WEKA Segmentation (TWS) tool (Arganda-Carreras et al., 2017) available in Fiji (Rueden et al., 2017) was used to train two separate Random Forest classifiers to automatically segment cartilage damage on ink stained cadaveric ovine stifle joints. Gold standard labels were manually annotated for the training, validation and test datasets for each of the femoral and tibial classifiers. Each dataset included a sample of medial and lateral femoral condyles and tibial plateaus from various stifle joints, selected to ensure no overlap across datasets according to ovine identifier. Training was performed on the training data with the TWS tool using edge, texture and noise reduction filters selected for their suitability and performance. The two trained classifiers were then applied to the validation data to output damage probability maps, on which a threshold value was calibrated. Model predictions on the unseen test set were evaluated against the gold standard labels using the Dice Similarity Coefficient (DSC) – an overlap-based metric, and compared with results for the baseline global threshold approach applied in Fiji as shown in Figures 1 and 2. Results. Test set results for the global threshold approach against gold standard labels were 45.0% DSC for the femoral condyle and 32.0% DSC for the tibial plateau. Results for the developed TWS classifiers on the same unseen test data were 79.0% and 72.7% DSC, showing absolute gains of 34.0% and 40.7% DSC over the global threshold baseline for the femoral and tibial classifiers. The trained TWS classifiers were then applied to an external set of unlabelled images of ink stained femoral condyles and tibial plateaus. Model results on sample images shown in Figure 3 further highlight the generalisation capability of the developed models. The most prominent classification features were Hessian filters (32.9%), Entropy (19.4%), Gaussian blur (10.1%), Gabor filters (6.3%) and Sobel filters (6.0%), with all other features contributing less than 6%. Conclusions. Our findings show that the developed segmentation method more accurately quantifies cartilage damage and provides improved generalisation capability over a range of input variations such as inconsistent orientation and lighting conditions. The developed model enables the use of articular cartilage damage as a reliable and quantitative outcome measure in studies involving large datasets, with reduced requirements for complex pre-processing and specialised equipment. For any figures or tables, please contact the authors directly

Knee arthroscopy is typically approached from the anterior, posteromedial and posterolateral portals. Access to the posterior compartments through these portals can cause iatrogenic cartilage damage and create difficulties in viewing the structures of the posterior compartments. The purpose of this study was to assess the feasibility of needle arthroscopy using direct posterior portals as both working and visualising portals. For workability, the needle scope was inserted advanced from anterior between the cruciate ligament bundle and the lateral wall of the medial femoral condyle until the posterior compartments were visualised. For visualisation, direct postero-lateral and -medial portals were established. The technique was performed in 9 knees by two experienced researchers. Workability and instrumentation of the posteromedial compartment and meniscus was achieved in 56%. The posterior horns could not be visualised in four specimens as the straight lens could not provide a more medial field of view. Visualisation from the direct medial posterior portal allowed a clear view of the medial meniscus, femoral condyle and posterior cruciate ligament in all specimens. Workability and instrumentation of the posterolateral compartment was not possible with the needle scope. Direct posterior approaches for the posteromedial compartment access are challenging with the current needle scope options and could only be achieved in over 50%. The postero-lateral compartment was not accessible. An angled lens or a flexible Needle scope would be better suited for developing this technique further

Introduction. Post-meniscectomy syndrome is broadly characterised by intractable pain following the partial or total removal of a meniscus. There is a large treatment gap between the first knee pain after meniscectomy and the eligibility for a TKA. Hence, there is a strong unmet need for a solution that will relieve this post-meniscectomy pain. Goal of this first-in-man study was to evaluate the safety and performance of an anatomically shaped artificial medial meniscus prosthesis and the accompanying surgical technique. Methods. A first-in-man, prospective, multi-centre, single arm clinical investigation was intended to be performed on 18 post-medial meniscectomy syndrome patients with limited underlying cartilage damage (Kellgren Lawrence scale 0–3) in the medial compartment and having a normal lateral compartment. Eventually 5 patients received a polycarbonate urethane mediale meniscus prosthesis (Trammpolin® medial meniscus prosthesis; ATRO Medical B.V., the Netherlands) which was clicked onto two titanium screws fixated at the native horn attachments on the tibia. PROMs were collected at baseline and at 6 weeks, 3, 6, 12 and 24 months following the intervention including X-rays at 6, 12 and 24 Months. MRI scans were repeated after 12 and 24 months. Results. The surgical technique to select the appropriately sized implant and correct positioning of the fixation screws and meniscus prosthesis onto the tibia was demonstrated feasible and reproducible. The surgeries showed that in particular the positioning of the posterior screw is crucial for correct positioning of the prosthesis. Inclusion stopped after 5 patients, who reached the 6 months evaluation. The PROMs did not improve in the first 6 months after surgery. All patients reported knee joint stiffness and slight effusion in their knee at 6 months follow-up. In case of symptomatic patients an evaluation of the device position and integrity was performed by MRI. In three patients the implants were removed because of implant failure and in one patient the implant was removed because of persistent pain and extension deficit. At present one patient has the implant still in situ. The explantations of the implants demonstrated no articular cartilage damage and the fixation screws were securely anchored. Discussion. This is the first clinical study with an artificial meniscus-like prosthesis. Except one, all implants were removed due to implant breakage or discomfort of the patient. Analysis of the torn implants showed fatigue failure resulting from the lack of loadsharing between implant and cartilage: the implant was too stiff and carried all the load in the medial compartment of the knee. Furthermore, the fixation with screws seemed too rigid which restricted the motion of the posterior horn. Based on previous in vitro and animal experiments, we expected more creep of the material and more motion on the screw fixation. Conclusion. This first-in-man clinical study demonstrates that the investigated device design is not safe and did not perform as expected. Therefore, modification of the meniscus prosthesis design and fixation technique is required to allow for more motion of the meniscus prosthesis during knee joint movement

Introduction. Acetabular fractures management is controversial since, despite a good anatomical reduction, clinical outcome is not satisfactory very often and the probability of a total hip arthroplasty (THA) is high. Surgical treatment include long operating times, large approach, blood loss, neural and muscle damage, and a high risk of failure and secondary osteoarthritis related to bone necrosis, cartilage damage, and bone loss. We hypothesized that the acetabular fracture management affected the clinical and radiological outcome of THA after posttraumatic arthritis. Materials and Methods. We compared 49 patients (49 hips) initially treated conservatively followed some months later by THA in conjunction with acetabular reconstruction (group 1); and 29 patients (29 hips) who had undergone THA after a failed osteosynthesis (group 2). There were more associated fractures according to Letournel in group 2. The mean age was 59.3±15.8 years for group 1 and 52.9±15.2 years for group 2. The mean delay between fracture and THA was 75.4±5 months for group 1 and 59.4±5 for group 2. The mean follow-up was 11.7 in group 1 and 10.2 in group 2. Preoperative bone defect was similar. We used bone autograft in 13 hips (26.5%) in group 1 and four (13.6%) in group 2. We used acetabular reconstruction plates in 2 hips with a pelvic discontinuity in group 1. Complications, clinical outcome according to Harris Hip Score, and radiological reconstruction were compared. Two-way ANOVA with repeated measures were used for comparison. Results. There were 5 cups revised for aseptic loosening in group 1 and 2 in group 2. The cumulative probability of not having a cup revision at 16 years was 90.6% (95% confidence interval (CI) 78,1 to 100) for group 1 and 94.1% (95% CI 86.5 to 100) for group 2 (p=0.76). There were 4 sciatic palsies in group 2, 4 of which developed after trauma and 2 after osteosynthesis. There were no infections. Although pre-operative clinical score was better in group 1, post-operatively at latest follow-up there were no differences. The radiological reconstruction was better in group 1 for version angle (p=0.03) and abductor lever arm (p=0.02). The change from the pre- to post-operative situation was greater in group 2 for the latter (Delta value, p=0.002). The rate of post-operative heterotopic ossifications was greater in group 2 (p=0.04). Conclusions. Long-term clinical and radiograph results are good in patients who underwent THA after a complex acetabular fracture, however, primary THA in conjunction with acetabular reconstruction had a lower number of complications and a better radiographic acetabular reconstruction than a THA after failed osteosynthesis

Introduction. There is interest in minimally invasive solutions that reduce osteoarthritic symptoms and restore joint mobility in the early stages of cartilage degeneration or damage. The aim of the present study was to evaluate the Biolox®delta alumina-zirconia composite as a counterface for articulation against live cartilage in comparison to the clinically relevant CoCrMo alloy using a highly controlled in vitro ball-on-flat articulation bioreactor that has been shown to rank materials in accord with clinical experience. Methods. The four-station bioreactor was housed in an incubator. The dual axis concept of this simulator approximates the rolling-gliding kinematics of the joint. Twelve 32 mm alumina-zirconia composite femoral heads (Biolox®delta, CeramTec GmbH, Germany) and twelve 32 mm CoCrMo femoral heads (Peter Brehm GmbH, Germany) made up the testing groups. Each head articulated against a cartilage disk of 14 mm diam., harvested from six months old steers. Free-swelling control disks were obtained as well. Testing was conducted in Mini ITS medium for three hours daily over 10 days applying a load of 40 N (∼2 MPa). PG/GAG was determined using the dimethylmethylene blue (DMMB) assay. Hydroxyproline was analyzed by high performance liquid chromatography coupled to a mass spectrometer. Additionally, at test conclusion, chondrocyte survival was determined using Live/Dead assay. Histological analysis was performed using a modified Mankin score. The effect of articulating material (ceramic, CoCrMo) on the various outputs of interest was evaluated using ANOVA. Blocking was performed with respect to the animals. The Mankin scores were compared using the Kruskal–Wallis test. Results. Cells stayed alive during the course of the 3-week experiment with cell survival values close to or at 80% at test completion. There was no difference between ceramic and free swelling control tissue. However, cell count values were inferior for CoCrMo in the superficial zone (p= 0.003). Tested tissue suffered mostly structural abnormalities. In many samples, the superficial layer was disturbed (and sometimes absent), but deeper layers were little affected. The average Mankin scores were in the range of 2 (out of 14) for both materials (p=0.772; Fig. 1). PG/GAG content in medium was highest for CoCrMo (Fig. 2). Though despite a 10% difference between CoCrMo and ceramic, this did not manifest in statistical significance (p=0.315). Similarly, hydroxyproline release into medium was higher for CoCrMo than ceramic (Fig. 3). This difference (28%) was statistically significant (p=0.024). Discussion. Overall, the results indicate that ceramic-on-cartilage induces less tissue and cell damage than metal-on-cartilage. However, only the hydroxyproline measurements reached statistical significance, partially due to a large variation within both material groups. Current understanding of cartilage wear is still incomplete. While studies have utilized the coefficient of friction against artificial materials as a surrogate wear marker, the best way to determine wear in in-vitro experiments is not well-established. Here, we used the matrix components proteoglycan and hydroxyproline to predict cartilage damage, but further work is necessary to elucidate the mechanobiological reasons for damage. In summary, from this study, Biolox®delta ceramic is generally superior to CoCrMo in the articulation against hyaline cartilage. For any figures or tables, please contact authors directly (see Info & Metrics tab above).

Joint hemiarthroplasty replaces one side of a synovial joint and is a viable alternative to total joint arthroplasty when one side of the joint remains healthy. Most hemiarthroplasty implants used in current clinical practice are made from stiff materials such as cobalt chrome or ceramic. The substitution of one side of a soft cartilage-on-cartilage articulation with a rigid implant often leads to damage of the opposing articular cartilage due to the resulting reductions in contact area and increases in cartilage stress. The improvement of post-operative hemiarthroplasty articular contact mechanics is of importance in advancing the performance and longevity of hemiarthroplasty. The purpose of the present study was to investigate the effect of hemiarthroplasty surface compliance on early in-vitro cartilage wear and joint contact mechanics. Cartilage wear tests were conducted using a six-station pin-on-plate apparatus. Pins were manufactured to have a hemispherical radius of curvature of 4.7 mm using either Bionate (DSM Biomedical) having varying compliances (80A [E=20MPa], 55D [E=35MPa], 75D [E=222MPa], n=6 for each), or ceramic (E=310GPa, n=5). Cartilage plugs were cored from fresh unfrozen bovine knee joints using a 20 mm hole saw and mounted in lubricant-containing chambers, with alpha calf serum diluted with phosphate buffer solution to a protein concentration of 17 g/L. The pins were loaded to 30N and given a stroke length of 10 mm for a total of 50,000 cycles at 1.2 Hz. Volumetric cartilage wear was assessed by comparing three-dimensional cartilage scans before and during wear testing. A two-way ANOVA was used for statistical analysis. To assess hemiarthroplasty joint contact mechanics, 3D finite element modelling (ABAQUS v6.12) was used to replicate the wear testing conditions. Cartilage was modeled using neo-Hookean hyper-elastic material properties. Contact area and peak contact stress were estimated. The more compliant Bionate 80A and 55D pins produced significantly less volumetric cartilage wear compared with the less compliant Bionate 75D and ceramic pins (p 0.05). In terms of joint contact mechanics, the more compliant materials (Bionate 80A and 55D) had significantly lower maximum contact stress levels compared to the less compliant Bionate 75D and ceramic pins (p < 0 .05). The results of this study show a relationship between hemiarthroplasty implant surface compliance and early in vitro cartilage wear, where the more compliant surfaces produced significantly lower amounts of cartilage wear. The results of the joint contact mechanics analysis showed that the more compliant hemiarthroplasty materials produced lower maximum cartilage contact stresses than the less compliant materials, likely related to the differences in wear observed. More compliant hemiarthroplasty surfaces may have the potential to improve post-operative cartilage contact mechanics by increasing the implant-cartilage contact area while reducing peak contact stress at the implant-cartilage interface, however, such materials must be resistant to surface fatigue and longer-term cartilage wear/damage must be assessed

This is a case series of a senior surgeon's experience; the purpose being to illustrate the problems encountered when using bio-absorbable anchors for various indications in shoulder surgery. Method. A retrospective analysis of 7 patients' notes, radiology and arthroscopic findings between 2006 and 2010. Results. There were 5 females and 2 males, with an average age of 50 years 3 months. The indications for using these anchors varied; 5 patients had rotator cuff repairs, 1 had a SLAP repair and the other had a Bankart repair. Patients complained of pain (3), a noisy shoulder (2), deformity (1) and symptoms similar to an infection (1). Average time from surgery to symptoms varied, with the shortest time being 3 months and the longest being 4 years 2 months. Some had dramatic MRI changes showing significant lysis around the anchors. Arthroscopic findings included anchor debris in the joint, loose anchors with significant defects and resultant irreversible cartilage damage. Conclusion. We conclude that even though these anchors are widely marketed and used in shoulder surgery, they are not without their problems, which can occur as early as three months post insertion. This has certainly changed our minds regards the use of bio-absorbable anchors in our practice

90% of young patients that develop DJD of the hip have an underlying structural problem, most frequently hip dysplasia. The structural problem results in decreased contact area, increased contact stresses about the anterior and lateral acetabulum and femoral head and results in labral pathology, early cartilage damage and if left untreated leads to end stage hip arthritis. Despite the optimism of alternative bearing surfaces and highly cross linked polyethylene, THA should still be discouraged in young patients. Many patients with symptomatic hip dysplasia in the absence of arthritis will benefit from joint preservation. The goal of treatment should be restoration of anatomy as close to normal as possible. The Bernese PAO is the preferred technique in many centres in North America and Europe because of its balance between minimal exposure, complications, and ability to provide optimal correction. The ideal patient for a PAO is young, has no arthritis, is not obese (BMI <30) and has poorly covered femoral head where congruency is possible. A PAO has advantages over other osteotomies and include: . 1). Performed through one incision without violation of the abductors. 2). Pelvic ring and an outlet, are not disrupted. 3). Posterior column is preserved. 4). Allow multidirectional correction. 5). Can perform capsulotomy to assess the labrum and check for impingement. The results of the osteotomy have been encouraging with up to 60% survivorship free from total hip arthroplasty at 20 years. Most studies show improvement in pain and function, improvement in radiographic coverage of the femoral head with no improvement in range of motion. Treatment should be individualised to each patient based on radiographic findings, age and cartilage status and restoration of anatomy as close to normal as possible should be the ideal treatment, most commonly in the form of a periacetabular osteotomy

Objective. High molecular weight hyaluronan (HA) is widely used in the treatment of osteoarthritis (OA) and rheumatoid arthritis (RA) by intra-articular injection. However, comparative studies of HA actions on catalytically activated cartilages in different pathologic conditions have rarely been investigated. Fibronectin fragments increased in OA and RA joints are known to cause cartilage damage through their catabolic activities. This study aimed to compare the inhibitory effects of HA on nitric oxide (NO) production by COOH-terminal heparin-binding fibronectin fragment (HBFN-f) between normal and diseased cartilages. Methods. Articular cartilage explants from normal, OA, or RA joints or isolated chondrocytes in monolayer were incubated with HBFN-f in the presence or absence of HA. Secreted NO levels in conditioned media were determined. Induction of inducible nitric oxide synthase (iNOS) and activation of nuclear factor-?B (NF-?B) were assessed with immunoblotting. Cultures were pre-treated with the specific inhibitor to evaluate the role of NF-?B in HBFN-f action. Immunofluorescence histochemistry was performed using fluoresceinated anti-CD44 antibody. Results. When articular cartilage explants from normal, OA, or RA joints were incubated with HBFN-f, the RA and OA cartilages produced higher levels of NO compared with normal cartilage. Pre-treatment with 2700 kDa HA resulted in significant suppression of HBFN-f-stimulated NO production in OA and RA cartilages. While CD44 was up-regulated in OA and RA cartilages, anti-CD44 antibody reversed HA inhibition of HBFN-f action in those cartilages. While NF-?B activation contributed to HBFN-f-stimulated NO production, HA inhibited HBFN-f-activated phosphorylation and nuclear translocation of NF-?B. Conclusion. The present results clearly demonstrated that HA blocked HBFN-f actions in OA and RA cartilages through interaction with CD44. Down-regulation of NF-?B could involve HA inhibition of HBFN-f action. Intra-articular administration of HA, which targets CD44 highly expressed on OA and RA chondrocytes, could suppress catabolic actions by fibronectin fragments like HBFN-f in diseased cartilage

Introduction. The low-cost, no-harm conditions associated with vibroarthography, the study of listening to the vibrations and sound patterns of interaction at the human joints, has made this method a promising tool for diagnosing joint pathologies. This current study focuses on the knee joint and aims to synchronize computational models with vibroarthographic signals via a comprehensive graphical user interface (GUI) to find correlations between kinematics, vibration signals, and joint pathologies. This GUI is the first of its kind to synchronize computational models with vibroarthographic signals and gives researchers a new advantage of analyzing kinematics, vibration signals, and pathologies simultaneously in an easy-to-use software environment. Methods. The GUI (Figure 1) has the option to view live or previously captured fluoroscopic videos, the corresponding computational model, and/or the pre- or post-processed vibration signals. Having more than one signal axes available allows for comparison of different filtering techniques to the same signal, or comparison of signals coming from different sensor placements (ex: medial vs. lateral femoral condyle). Using computational models derived using fluoroscopic data synchronized with the vibration signals, the areas of contact between articulating surfaces can be mapped for the in vivo signal (figure 2). This new method gives the opportunity to find correlations between the different sensor signals and contact maps with the diagnosis and cartilage degeneration map, provided by a surgeon, during arthroscopy or TKA implantation (figure 3). Results. Using previously captured data and newly acquired data for subjects from research studies, several different knee pathologies have been analyzed. The signals were listened to audibly after being processed to add a qualitative side. Sounds coming from knees with pathologies revealed noticeable differences compared to the healthy subjects, and the quantitative analysis further supported our hypothesis (>96% accuracy classification patella arthritic subjects vs. healthy). Discussion. Ideally, transitioning towards real-time kinematic tracking with signal acquisition allows for diagnostic screening tools of the knee joint that will provide feedback of cartilage damage maps as well as potential meniscal or ligament injuries. The method used in this study is multi-faceted in that it allows the subject to perform various daily weight or non-weight bearing activities at his/her own speed which makes it easier to use than if the subject had to be in a very controlled environment

INTRODUCTION. The menisci play a fundamental biomechanical role in the knee and also help in the maintaining of the articular homeostasis; thus, either a lesion or the complete absence of the menisci can invalidate the physiological function of the knee causing important damages, even at long term. Unfortunately, meniscal tears are often found during the ordinary orthopaedic practice while the regenerative potential of this kind of tissue is very low and limited to its peripheral-vascularized part; this is why the majority of these common arthroscopic findings are not reparable and often the surgeon is almost forced to perform a partial, subtotal or even total meniscectomy, regardless of the well-known consequences of this kind of surgery. MATERIALS AND METHODS. Recently a porous, biodegradable scaffold made of an aliphatic polyurethane (Actifit(tm),Orteq Ltd) has been developed for the arthroscopic treatment of partial and irreparable meniscal tears; thanks to its particular structure, this scaffold facilitates the regeneration of the removed meniscal part, preventing the potential cartilage damage due to its complete or partial lack. We performed a prospective clinical study on 17 patients affected by a massive loss of meniscal substance either medial or lateral associated with intraarticular or global knee pain and/or swelling. We analyzed the patient both clinically and by using the International Knee Document Committee's (IKDC) Subjective and Objective Knee Evaluation Form. We also assessed the sport activity resumption by comparing the Tegner score at the time of the very first visit with the presurgery and prelesional ones. Finally, we also organized a control MRI at 6 and 12 months after surgery. DISCUSSION. Our preliminary results are encouraging and they confirm the clinical experiences of other study groups. Apparently, the properties of this scaffold help in vessels formation and tissue regeneration potentially allowing the restoration of the surgically removed portion and preventing, or delaying at least, both chondral and articular degeneration. We also performed some biopsy associated arthroscopic “second-looks” that reinforced the already good clinical results; the biopsies also confirmed the new tissue ingrowth into the biomaterial, potentially leading to the replacement of the previously removed damaged tissue. CONCLUSIONS. Preliminary results suggest that this surgical procedure can be considered a really promising method for the treatment of both inveterate and symptomatic meniscal tears; however, other randomized studies with a longer follow-up should be done to confirm its reliability and potentialities

[Background]. Bipolar hemiarthroplasty (following BHA) have historically had poor results in patients with idiopathic osteonecrosis of femoral head (OFNH). However, most recent report have shown excellent results with new generation BHA designs that incorporate advances in bearing technology. These optimal outcomes with bipolar hemiarthroplasty will be more attractive procedure for young patients who need bone stock for future total arthroplasty. The purpose of the current study was to evaluate the clinical and radiographic finding of this procedure for the treatment of OFNH at our institution after 7-to 21years follow-up. [Subjects and Methods]. We retrospectively reviewed a consecutive series of 29 patients (40 hips) who underwent primary bipolar hemiarthroplasty for ION (36 hips with stage III and 4 hips with stage IV) with a cementless femoral component between 1992 and 2006. Osteonecrosis was associated with corticosteroid use (23 patients), alcohol (16 patients), idiopathic (one patients). The mean follow-up duration was approximately 12 (range 7 to 21) years. Patients were evaluated according to the Japan Orthopaedic Association (JOA) hip score. We evaluate osteolysis and bone response of acetabulum or femur, and migration distance of outer head were calculated at the latest follow-up. Kaplan-Meier survivorship rate was investigated to examine implant failure rate. [Results]. The average the Japan Orthopedic Association (JOA) hip score significantly improved from 53.9±16.0 points (preoperative) to 89.6±8.0 points (final follow-up). At the time of the final follow-up, one patients (one hips) had undergone revision to total hip arthroplasty because of groin pain without mechanical failure and migration. The rate of implant survival, with revision because of any reason as the end point, was 100% for femoral components and 97.5% for bipolar head components at a average 12 years (139.9±51.1 months) respectively. A complication that include dislocation and disassembly was not occurred in this study group. Radiographically, all cases is acquired bone ingrowth fixation. Stress shielding of femoral-component was observed 13 cases (32.5%). No femoral-component loosening and osteolysis of femur and acetabular was occurred at final follow-up. Bipolar head shift greater than 2mm is 3cases (7.5%) at final follow-up point, but progressive outer head migration was not occurred (0 %). [Discussion]. Survivorship determined in our study was more favorable than that of previous studies. The our long-term postoperative clinical results of up to Stage3 without the acetabular cartilage surface damage showed more superior to those previously reported for BHA. Recently, larger oscillation angle, proximal porous coating, highly cross-linked PE liner, improved these BHA design concept. Thus, the current BHA can be one of reliable procedure. Based on our results, The BHA for stage III ION, with appropriate surgical indications, may be a good option

Hyaline articular cartilage has been known to be a troublesome tissue to repair once damaged. Since the introduction of autologous chondrocyte implantation (ACI) in 1994, a renewed interest in the field of cartilage repair with new repair techniques and the hope for products that are regenerative have blossomed. This article reviews the basic science structure and function of articular cartilage, and techniques that are presently available to effect repair and their expected outcomes.

Bone-marrow oedema can occur both in isolation and in association with necrosis of bone, but it has not been shown whether each respond to the same methods of treatment.

We treated 16 patients with isolated oedema and 17, in which it was associated with necrosis of the proximal femur, with the prostacyclin derivative iloprost, which has been shown to be effective in the idiopathic form. The Harris hip score, the range of movement, the extent of the oedema as measured by MRI, pain on a visual analogue scale and patient satisfaction were recorded before and subsequent to treatment.

In both groups, we were able to show a significant improvement (p < 0.001) in these observations during the period of follow-up indicating that iloprost will produce clinical improvement in both circumstances.