Cartilage repair remains a major challenge in human orthopedic medicine, necessitating the application of innovative strategies to overcome existing technical and clinical limitations. Adhesive hydrogels have emerged as promising candidates for cartilage repair promotion and tissue engineering, offering key advantages such as enhanced tissue integration and therapeutic potential. This comprehensive review navigates the landscape of adhesive hydrogels in cartilage repair, discussing identified challenges, shortcomings of current treatment options, and unique advantages of adhesive hydrogel products and scaffolds. While emphasizing the critical need for in situ lateral integration with surrounding tissues, we dissect current limitations and outline future perspectives for hydrogel scaffolds in cartilage repair. Moreover, we examine the clinical translation pathway and regulatory considerations specific to adhesive hydrogels. Overall, this review synthesizes the existing insights and knowledge gaps and highlights directions for future research regarding adhesive hydrogel-based devices in advancing cartilage tissue engineering.

This classic discusses the original publication "A method of resurfacing osteoarthritic knee joints" by Dr K.H. Pridie (1959), where this pioneer surgeon described a newly developed method for the treatment of osteoarthritic joint surfaces of the knee, which he named subchondral drilling. This short and concise 11-line publication appeared in the Proceedings of the Congress of the British Orthopaedic Association. It has generated 464 citations since 1959, becoming part of the hundred most-cited publications in knee research. Pridie introduced in clinical experimentation the entity of Marrow Stimulation Techniques to liberate mesenchymal stem cells from cancellous bone. He was aware that the results induced, in terms of quality of the regrown tissue, was limited and "only" fibrocartilage. His idea might have been raised from the work of numerous animal researchers who confirmed repeatedly since 1905 that cartilage needed an osseous perforation to heal. Although the past 60 years brought modifications from the technique described in the original article, the concept of marrow stimulation introduced by Pridie remains the most frequently used in cartilage repair surgery today.

Cultured autologous human articular chondrocyte (HAC) implantation has been extensively investigated for safe and effective promotion of structural and functional restoration of knee cartilage lesions. HAC-based cytotherapeutic products for clinical use must be manufactured under an appropriate quality assurance system and follow good manufacturing practices (GMP). A prospective clinical trial is ongoing in the Lausanne University Hospital, where the HAC manufacturing processes have been implemented internally. Following laboratory development and in-house GMP transposition of HAC cell therapy manufacturing, a total of 47 patients have been treated to date. The main aim of the present study was to retrospectively analyze the available manufacturing records of the produced HAC-based cytotherapeutic products, outlining the inter-individual variability existing among the 47 patients regarding standardized transplant product preparation. These data were used to ameliorate and to ensure the continued high quality of cytotherapeutic care in view of further clinical investigations, based on the synthetic analyses of existing GMP records. Therefore, a renewed risk analysis-based process definition was performed, with specific focus set on process parameters, controls, targets, and acceptance criteria. Overall, high importance of the interdisciplinary collaboration and of the manufacturing process robustness was underlined, considering the high variability (i.e., quantitative, functional) existing between the treated patients and between the derived primary HAC cell types.

While many injectable viscosupplementation products are available for osteoarthritis (OA) management, multiple hydrogel functional attributes may be further optimized for efficacy enhancement. The objective of this study was to functionally benchmark four commercially available hyaluronan-based viscosupplements (Ostenil, Ostenil Plus, Synvisc, and Innoryos), focusing on critical (rheological, lubricative, adhesive, and stability) attributes. Therefore, in vitro and ex vivo quantitative characterization panels (oscillatory rheology, rotational tribology, and texture analysis with bovine cartilage) were used for hydrogel product functional benchmarking, using equine synovial fluid as a biological control. Specifically, the retained experimental methodology enabled the authors to robustly assess and discuss various functional enhancement options for hyaluronan-based hydrogels (chemical cross-linking and addition of antioxidant stabilizing agents). The results showed that the Innoryos product, a niacinamide-augmented linear hyaluronan-based hydrogel, presented the best overall functional behavior in the retained experimental settings (high adhesivity and lubricity and substantial resistance to oxidative degradation). The Ostenil product was conversely shown to present less desirable functional properties for viscosupplementation compared to the other investigated products. Generally, this study confirmed the high importance of formulation development and control methodology optimization, aiming for the enhancement of novel OA-targeting product critical functional attributes and the probability of their clinical success. Overall, this work confirmed the tangible need for a comprehensive approach to hyaluronan-based viscosupplementation product functional benchmarking (product development and product selection by orthopedists) to maximize the chances of effective clinical OA management.

Background: Multiligament reconstruction (MLR) has become the standard surgical approach for treating multiligament knee injuries (MLKIs). Purpose: To identify prognostic factors for patient-reported outcome measures, return to work (RTW), return to sports, and radiographic osteoarthritis (OA) (Kellgren-Lawrence grade ≥2) after MLR for MLKI. Study Design: Case-control study; Level of evidence 3. Methods: Included were 52 consecutive patients (age, 35.5 ± 11 years; 75% men), with MLKI sustained between 2013 and 2019 and treated with MLR. At a mean follow-up of 3.8 ± 1.6 years, patient-reported outcome measure scores—including the International Knee Documentation Committee (IKDC), the Knee injury and Osteoarthritis Outcome Score (KOOS), the Anterior Cruciate Ligament–Return to Sport after Injury (ACL-RSI), and the 12-Item Short-Form Health Survey—RTW, return to sports, and weightbearing radiographs were obtained. A total of 20 determinants were hypothesized and tested by univariate logistic regression for binary variables or linear regression for continuous variables. Only factors identified as significant ( P < .10) were entered into a multivariate logistic regression model. Results: The prevalence of injury severity according to the Schenck knee dislocation (KD) classification was as follows: KD I (44%), KD III (36%), KD IV (10%), and KD V (10%). Increased KD grades resulted in decreased IKDC ( P = .002) and all 5 KOOS subscales ( P≤ .007 for all) scores. Medial meniscectomy (23%) was associated with a worse ACL-RSI score ( P = .007) and RTW failure (odds ratio [OR], 36.8; P = .035). Peroneal nerve palsy (6%) was associated with a worse ACL-RSI score ( P≤ .001). Radiographic OA was observed in 38%, with distribution predominantly patellofemoral (80%) and medial tibiofemoral (45%). Traumatic cartilage damage (Outerbridge grade >2 [37%]) was associated with secondary patellofemoral (OR, 10; P = .012) and medial tibiofemoral (OR, 10; P = .019) OA. Anterior cruciate ligament reconstruction failure (7%) was a risk factor for medial tibiofemoral OA (OR, 25.8; P = .006). Conclusion: Increased Schenck KD grade, permanent peroneal nerve palsy, and irreparable medial meniscus lesions were prognostic factors for worse functional outcomes 3.8 years after MLKI was treated with MLR. Traumatic cartilage damage and anterior cruciate ligament failure were associated with the development of early OA.