Association between intraarticular cytokine levels and clinical parameters of osteochondritis dissecans in the ankle

Critical signaling molecules in the temporomandibular joint osteoarthritis under different magnitudes of mechanical stimulation

The mechanical stress environment in the temporomandibular joint (TMJ) is constantly changing due to daily mandibular movements. Therefore, TMJ tissues, such as condylar cartilage, the synovial membrane and discs, are influenced by different magnitudes of mechanical stimulation. Moderate mechanical stimulation is beneficial for maintaining homeostasis, whereas abnormal mechanical stimulation leads to degeneration and ultimately contributes to the development of temporomandibular joint osteoarthritis (TMJOA), which involves changes in critical signaling molecules. Under abnormal mechanical stimulation, compensatory molecules may prevent degenerative changes while decompensatory molecules aggravate. In this review, we summarize the critical signaling molecules that are stimulated by moderate or abnormal mechanical loading in TMJ tissues, mainly in condylar cartilage. Furthermore, we classify abnormal mechanical stimulation-induced molecules into compensatory or decompensatory molecules. Our aim is to understand the pathophysiological mechanism of TMJ dysfunction more deeply in the ever-changing mechanical environment, and then provide new ideas for discovering effective diagnostic and therapeutic targets in TMJOA.

Ankle Sprains in Athletes: Current Epidemiological, Clinical and Imaging Trends

Purpose

Ankle injuries are frequent sports injuries. Despite optimizing treatment strategies during recent years, the percentage of chronification following an ankle sprain remains high. The purpose of this review article is, to highlight current epidemiological, clinical and novel advanced cross-sectional imaging trends that may help to evaluate ankle sprain injuries.

Methods

Systematic PubMed literature research. Identification and review of studies (i) analyzing and describing ankle sprain and (ii) focusing on advanced cross-sectional imaging techniques at the ankle.

Results

The ankle is one of the most frequently injured body parts in sports. During the COVID-19 pandemic, there was a change in sporting behavior and sports injuries. Ankle sprains account for about 16-40% of the sports-related injuries. Novel cross-sectional imaging techniques, including Compressed Sensing MRI, 3D MRI, ankle MRI with traction or plantarflexion-supination, quantitative MRI, CT-like MRI, CT arthrography, weight-bearing cone beam CT, dual-energy CT, photon-counting CT, and projection-based metal artifact reduction CT may be introduced for detection and evaluation of specific pathologies after ankle injury. While simple ankle sprains are generally treated conservatively, unstable syndesmotic injuries may undergo stabilization using suture-button-fixation. Minced cartilage implantation is a novel cartilage repair technique for osteochondral defects at the ankle.

Conclusion

Applications and advantages of different cross-sectional imaging techniques at the ankle are highlighted. In a personalized approach, optimal imaging techniques may be chosen that best detect and delineate structural ankle injuries in athletes.

Osteochondritis dissecans of the knee: Epidemiology, etiology, and natural history

Osteochondritis dissecans of the knee is a disease that typically affects skeletally immature patients. Clinically manifested with knee pain, limping, and joint disfunction, this condition has remained misunderstood and undervalued for a long period. Although being a rare condition, its awareness is of utmost clinical interest because of the possible severe consequences it can bring when misrecognized or inadequately treated. Its etiology remains unclear and is still debated. Many theories have been proposed, including inflammation, local ischemia, subchondral ossification abnormalities, genetic factors, and repetitive mechanical microtrauma, with a likely interplay of the same. This review article aims to deliver and discuss current and up-to-date concepts on epidemiology, etiology, and natural history of this pediatric condition. Level of evidence: level V.

Plausible mechanisms of and techniques to assess ankle joint degeneration following lateral ankle sprains: a narrative review

Lateral ankle sprain (LAS) is the most common lower extremity musculoskeletal injury sustained during daily life and sport. The cascade of events that starts with ligamentous trauma leads to clinical manifestations such as recurrent sprains and giving way episodes, hallmark characteristics of chronic ankle instability (CAI). The sequelae of lateral ankle sprains and CAI appear to contribute to aberrant biomechanics. Combined, joint trauma and aberrant biomechanics appear to directly and/or indirectly play a role in talar cartilage degeneration. Up to 80% of all cases of ankle osteoarthritis (OA) are post-traumatic in nature and common etiologies for ankle post-traumatic osteoarthritis (PTOA) are histories of a single and recurrent ankle sprains. Despite known links between LAS, CAI, and PTOA and evidence demonstrating the burden of LAS and its sequelae, early pathoetiological changes of ankle PTOA and how they can be assessed are poorly understood. Therefore, the purpose of this paper is to review the plausible mechanistic links among LAS and its sequelae of CAI and PTOA as well as review non-surgical techniques that can quantify talar cartilage health. Understanding the pathway from ligamentous ankle injury to ankle PTOA is vital to developing theoretically sound therapeutic interventions aimed at slowing ankle PTOA progression. Further, directly assessing talar cartilage health non-surgically provides opportunities to quantify if current and novel intervention strategies are able to slow the progression of ankle PTOA.

Increased cytokine levels and histological changes in cartilage, synovial cells and synovial fluid after malleolar fractures

BACKGROUND

Malleolar fractures are among the most common fractures in the human skeleton with a high risk of later development of post-traumatic osteoarthritis (OA). The acute ankle injury initiates a sequence of events potentially leading to progressive articular surface damage resulting from inflammatory changes in cartilage, synovial tissue and synovial fluid. We hypothesised that in the acute phase of ankle fracture, these changes occur at the same time in the different tissues.

METHODS

Specimens of chondral tissue, synovial tissue and synovial fluid were collected from 16 patients with acute articular ankle fracture (study group). Additional samples were obtained from five male fresh cadavers within 12 hours of death (control group). Chondral tissue was assessed for cellularity, irregularities and chondrocyte disarray. Synovial tissue was assessed for synovitis, proteoglycans and collagen deposition. Synovial fluid was assessed for cytokines IL-2, IL-6, IL-10, IL-17, IFN-γ and TGF-β1.

RESULTS

Chondral tissue showed discontinuity in the tidemark between cartilage and subchondral bone, chondrocyte disarray, increased cellularity (both at the cartilage surface and subchondral bone), articular surface irregularities and increased deposition of proteoglycans and collagen fibres. Synovial tissue showed a statistically significant difference between the study and control groups in the concentration per tissue area of both thin collagen fibres (p=0.0274) and thick collagen fibres (p<0.0001). Cytokine concentrations in synovial fluid samples were significantly higher in ankle fracture tissue compared with controls for IL-2 (p=0.0002), IL-6 (p<0.0001), IL-10 (p=0.002) and IL-17 (p<0.0001). No statistically significant differences were observed for IFN-γ (p=0.06303) and TGF-β1 (p=0.8832).

CONCLUSION

We observed a pattern of simultaneous and interrelated pathological changes in cartilage, subchondral bone, synovial tissue and synovial fluid after acute malleolar fracture. As the observed inflammatory changes could lead to the development of OA, a more thorough knowledge of these early processes could be helpful to find strategies for prevention or delay of this common complication.

Reoperation rates following ankle ligament procedures performed with and without concomitant arthroscopic procedures

PURPOSE

Over 50 % of the patients with chronic lateral ankle instability present with some degree of intra-articular pathology. To date, no consensus regarding the concomitant ankle arthroscopy procedures along with ankle ligament procedures has been reached. The purpose of current study was to investigate reoperation rates and postoperative complications following ankle ligament procedures with and without concomitant arthroscopic procedures.

METHODS

Reoperations and postoperative complications following ankle ligament procedures with and without concomitant arthroscopic procedures were investigated using the PearlDiver Patient Record Database (PearlDiver Technologies, Inc.; Fort Wayne, IN, USA) between 2007 and 2011. Ankle ligament procedures, including ligament repair and reconstruction, and ankle arthroscopic procedures were investigated as primary surgery. Subsequently, the reoperation procedures, including ankle ligament procedures, arthroscopic procedures, autologous osteochondral transplantation, and ankle arthrodesis, as well as wound complications and nerve injury following primary ankle ligament procedures were identified.

RESULTS

In 8014 patients receiving ligament repair, the arthroscopic group had a significantly higher reoperation rate in comparison with the non-arthroscopic group (8.8 vs. 6.5 %, odds ratio: 1.1, [p < 0.01], 95 % confidence interval (CI) 1.2-1.7). However, the non-arthroscopic group included 29 open arthrodesis procedures following the primary surgery, whereas arthroscopic group had none. Of the 8055 patients who received a ligament reconstruction, there was no significant difference in reoperation rate between the groups (5.9 vs. 5.9 %, odds ratio: 1.0, [n.s], 95 % CI 0.8-1.2). As seen in the ligament repair group, the non-arthroscopic group had a 4.9 % rate of ankle arthrodesis as a secondary procedure. Arthroscopic group had a significantly lower rate of wound dehiscence following ankle ligament procedures than non-arthroscopic group.

CONCLUSION

Concomitant ankle arthroscopy procedures performed with ankle ligament procedures did not decrease the rate of reoperation. However, there was a lower incidence of ankle arthrodesis and a lower rate of wound complications in the arthroscopic group when compared to those in non-arthroscopic group. Based on the results of the study, which analysed 16.069 patients, concomitant ankle arthroscopy is recommended.

LEVEL OF EVIDENCE

IV.

Prospective clinical trial of patients who underwent ankle arthroscopy with articular diseases to match clinical and radiological scores with intra-articular cytokines

OBJECTIVE

There is still a lack of reliable data on cytokine concentrations in the ankle and their value for prognosis.

METHODS

In a prospective clinical trial, lavage fluids were collected from 49 patients with an arthroscopy of the ankle. The fluids were investigated by ELISA for cytokine levels. Clinical scores (FFI, AOFAS) were evaluated both pre-operatively and then again 12 months after surgery (n = 43, 88%). Radiological changes were noted with the Kellgren-Lawrence-Score (KLS) and the Ankle Osteoarthritis Scoring System (AOSS). Based on the difference between the pre- and postoperative clinical scores, two groups were defined according to whether they had benefited from the surgical therapy (Δ score ≥ 10) or not (Δ score < 10).

RESULTS

The average clinical scores had improved to a statistically significant extent in the one-year follow-up (p < 0.01). BMP-2 (p = 0.02), IGF-1 (p = 0.04), BMP-7 (p = 0.01) and aggrecan (p = 0.04) showed significant correlations with pre-operative clinical and radiological scores (p = 0.02, p = 0.01, p = 0.01, p = 0.01). Furthermore, BMP-2 (p = 0.01), IGF-1/TPC (p = 0.03) and aggrecan (p = 0.01) correlated with scores after one year (p = 0.02, p = 0.01). High aggrecan concentrations were associated with a low clinical and a high radiological score at both time points, both indicating progress of cartilage degeneration in contrast to BMP-2 or IGF-1. Furthermore, MMP-13 concentrations were significantly higher in the non-benefit group (p = 0.02).

CONCLUSION

BMP-2, IGF-1, aggrecan and MMP-13 seem to be involved in the degenerative process of cartilage in the ankle joint. Additionally, high synovial MMP-13 concentrations indicate a worse clinical outcome.