Trends in arthroscopy-documented cartilage injuries of the knee and repair procedures among 15-60-year-old patients

Cartilage Restoration Prior to Primary Total Knee Arthroplasty

Cartilage restoration procedures are effective for articular defects of the knee. However, studies suggest decreased clinical improvements after total knee arthroplasty (TKA). The purpose of this study was to compare patients who had a prior cartilage restoration undergoing TKA with patients who had TKA without a prior cartilage restoration procedure. We specifically assessed (1) 90-day and 1-year medical/surgical complications; (2) 90-day and 1-year revision rates; and (3) 90-day costs. A search using a national, all-payer database examined matched cohorts of patients who underwent cartilage restoration procedures prior to TKA (n=22,072) and controls who did not (n=220,364) between January 1, 2010, and April 30, 2020. Cartilage restoration procedures included autologous chondrocyte implantation, microfracture, osteochondral autograft transfer system operations, or open and arthroscopic osteochondral allograft transplantation. Outcomes studied included lengths of stay, 30-day readmission rates, 90-day costs, and medical and surgical complications to include 90-day and 1-year prosthetic joint infections, pathologic fractures, dislocations, knee manipulations, and revisions. Comparable rates of 90-day and 1-year medical and surgical complications were found for TKAs after cartilage restoration. Additionally, 90-day and 1-year revision surgery rates were similar. These patients were also found to have 90-day costs almost identical to those of patients who did not have cartilage restoration. This large analysis of patients with cartilage restoration procedures prior to TKA demonstrated that the complication rates may be similar to those of patients who do not have these operations before TKA. These findings provide valuable information to surgeons and patients when deciding to proceed with TKA after cartilage restoration. [Orthopedics. 2023;46(4):250-255.].

Challenges in osteoarthritis treatment

Osteoarthritis (OA) is the most common form of arthritis and a degenerative joint cartilage disease that is the most common cause of disability in the world among the elderly. It leads to social, psychological, and economic costs with financial consequences. The principles of OA treatment are to reduce pain and stiffness as well as maintain function. In recent years, due to a better understanding of the underlying pathophysiology of OA, a number of potential therapeutic advances have been made, which include tissue engineering, immune system manipulation, surgical technique, pharmacological, and non-pharmacological treatments. Despite this, there is still no certain cure for OA, and different OA treatments are usually considered in relation to the stage of the disease. The purpose of the present review is to summarize and discuss the latest results of new treatments for OA and potential targets for future research.

Knee registries: state of the art

Sports injuries, trauma and the globally ageing and obese population require increasing levels of knee surgery. Shared decision making has replaced the paternalistic approach to patient management. Evidence-based medicine underpins surgical treatment strategies, from consenting an individual patient to national healthcare system design. The evolution of successful knee-related registries starting from specific arthroplasty registries has given rise to ligament reconstruction, osteotomy and cartilage surgery registries developing as platforms for surgical outcome data collection. Stakeholders include surgeons and their patients, researchers, healthcare systems, as well as the funding insurers and governments. Lately, implant manufacturers have also been mandated to perform postmarket surveillance with some hoping to base that on registry data. Aiming to assess the current status of knee-related registries, we performed a comprehensive literature and web search, which yielded 23 arthroplasty, 8 ligament, 4 osteotomy and 3 articular cartilage registries. Registries were evaluated for their scope, measured variables, impact and limitations. Registries have many advantages as they aim to increase awareness of outcomes; identify trends in practice over time, early failing implants, outlier surgeon or institution performance; and assist postmarketing surveillance. International collaborations have highlighted variations in practice. The limitations of registries are discussed in detail. Inconsistencies are found in collected data and measured variables. Potential measurement and selection biases are outlined. Without mandated data collection and with apparent issues such as unverified patient reporting of complications, registries are not designed to replace adverse event recording in place of a proper safety and efficacy study, as demanded by regulators. Registry 'big data' can provide evidence of associations of problems. However, registries cannot provide evidence of causation. Hence, without careful consideration of the data and its limitations, registry data are at risk of incorrectly drawn conclusions and the potential of misuse of the results. That must be guarded against. Looking at the future, registry operators benefit from a collective experience of running registries as they mature, allowing for improvements across specialties. Large-scale registries are not only of merit, improving with stakeholder acceptance, but also are critical in furthering our understanding of our patients' outcomes. In doing so, they are a critical element for our future scientific discourse.

The Impact of Training on the Loss of Cardiorespiratory Fitness in Aging Masters Endurance Athletes

Elite masters endurance athletes are considered models of optimal healthy aging due to the maintenance of high cardiorespiratory fitness (CRF) until old age. Whereas a drop in VO2max in masters athletes has been broadly investigated, the modifying impact of training still remains a matter of debate. Longitudinal observations in masters endurance athletes demonstrated VO2max declines between -5% and -46% per decade that were closely related to changes in training volume. Here, using regression analyses, we show that 54% and 39% of the variance in observed VO2max decline in male and female athletes, respectively is explained by changes in training volume. An almost linear VO2max decrease was observed in studies on young and older athletes, as well as non-athletes, starting a few days after training cessation, with a decline of as much as -20% after 12 weeks. Besides a decline in stroke volume and cardiac output, training cessation was accompanied by considerable reductions in citrate synthase and succinate dehydrogenase activity (reduction in mitochondrial content and oxidative capacity). This reduction could largely be rescued within similar time periods of training (re)uptake. It is evident that training reduction or cessation leads to a considerably accelerated VO2max drop, as compared to the gradual aging-related VO2max decline, which can rapidly nullify many of the benefits of preceding long-term training efforts.

Rehabilitation Variability Following Osteochondral Autograft and Allograft Transplantation of the Knee

OBJECTIVE

The aim of this study is to assess the variability of postoperative rehabilitation protocols used by orthopedic surgery residency programs for osteochondral autograft transplantation (OAT) and osteochondral allograft transplantation (OCA) of the knee.

DESIGN

Online postoperative OAT and OCA rehabilitation protocols from US orthopedic programs and the scientific literature were reviewed. A custom scoring rubric was developed to analyze each protocol for the presence of discrete rehabilitation modalities and the timing of each intervention.

RESULTS

A total of 16 programs (10.3%) from 155 US academic orthopedic programs published online protocols and a total of 35 protocols were analyzed. Twenty-one protocols (88%) recommended immediate postoperative bracing following OAT and 17 protocols (100%) recommended immediate postoperative bracing following OCA. The average time protocols permitted weight-bearing as tolerated (WBAT) was 5.2 weeks (range = 0-8 weeks) following OAT and 6.2 weeks (range = 0-8 weeks) following OCA. There was considerable variation in the inclusion and timing of strength, proprioception, agility, and pivoting exercises. Following OAT, 2 protocols (8%) recommended functional testing as criteria for return to sport at an average time of 12.0 weeks (range = 12-24 weeks). Following OCA, 1 protocol (6%) recommended functional testing as criteria for return to sport at an average time of 12.0 weeks (range = 12-24 weeks).

CONCLUSION

A minority of US academic orthopedic programs publish OAT and OCA rehabilitation protocols online. Among the protocols currently available, there is significant variability in the inclusion of specific rehabilitation components and timing of many modalities. Evidence-based standardization of elements of postoperative rehabilitation may help improve patient care and subsequent outcomes.

Engineering Closed-Loop, Autoregulatory Gene Circuits for Osteoarthritis Cell-Based Therapies

PURPOSE OF REVIEW

Genetic engineering offers the possibility to simultaneously target multiple cellular pathways in the joints affected by osteoarthritis (OA). The purpose of this review is to summarize the ongoing efforts to develop disease-modifying osteoarthritis drugs (DMOADs) using genetic engineering, including targeting approaches, genome editing techniques, and delivery methods.

RECENT FINDINGS

Several gene circuits have been developed that reprogram cells to autonomously target inflammation, and their efficacy has been demonstrated in chondrocytes and stem cells. Gene circuits developed for metabolic disorders, such as those targeting insulin resistance and obesity, also have the potential to mitigate the impact of these conditions on OA onset and/or progression. Despite the strides made in characterizing the inflammatory environment of the OA joint, our incomplete understanding of how the multiple regulators interact to control signal transduction, gene transcription, and translation to protein limits the development of targeted disease-modifying therapeutics. Continuous advances in targeted genome editing, combined with online toolkits that simplify the design and production of gene circuits, have the potential to accelerate the discovery and clinical application of multi-target gene circuits with disease-modifying properties for the treatment of OA.

Clinical and quality-of-life outcomes of a combined synthetic scaffold and autogenous tissue graft procedure for articular cartilage repair in the knee

Background

Injuries to the articular cartilage of the knee often fail to heal properly due to the hypocellular and avascular nature of this tissue. Subsequent disability can limit participation in sports and decrease quality of life. Subchondral bone perforations are used for the treatment of small defects. Filling out the central portion in larger lesions becomes difficult, and scaffolds can be used as adjuvants, providing a matrix onto which the defect can be filled in completely. Also, autogenous cartilage grafts can be combined, acting as an inducer and improving healing quality, all in a single procedure.

Methods

This observational study evaluated the clinical and quality-of-life outcomes of patients with articular cartilage lesions of the knee undergoing repair via a microfracture technique combined with a synthetic scaffold and autogenous cartilage graft, with transosseous sutures and fibrin glue fixation, at 12 months of follow-up. Secondarily, it assessed whether combined procedures, previous surgical intervention, traumatic aetiology, lesion location, and age affect outcomes. The sample consisted of adult patients (age 18–66 years) with symptoms consistent with chondral or osteochondral lesions, isolated or multiple, ICRS grade III/IV, 2–12 cm² in size. Patients with corrected angular deviations or instabilities were included. Those with BMI > 40 kg/m², prior total or subtotal (> 30%) meniscectomy, second-look procedures, and follow-up < 6 months were excluded. Pain (VAS), physical activity (IKDC), osteoarthritis (WOMAC), and general quality of life (SF-36) were assessed.

Results

64 procedures were included, comprising 60 patients. There was significant improvement (P < 0.05) in VAS score (5.92–2.37), IKDC score (33.44–56.33), and modified WOMAC score (53.26–75.93) after surgery. The SF-36 showed significant improvements in the physical and mental domains (30.49–40.23 and 46.43–49.84 respectively; both P < 0.05).

Conclusions

Combination of microfractures, autogenous crushed cartilage graft, synthetic scaffold, and transosseous sutures with fibrin glue provides secure fixation for treatment of articular cartilage lesions of the knee. At 12-month follow-up, function had improved by 20 points on the IKDC and WOMAC, and quality of life, by 10 points on the SF-36. Age > 45 years had a negative impact on outcomes.

Recent Developments in Clinical Applications of Mesenchymal Stem Cells in the Treatment of Rheumatoid Arthritis and Osteoarthritis

Mesenchymal stem cell (MSC) therapies have been used as cell-based treatments for decades, owing to their anti-inflammatory, immunomodulatory, and regenerative properties. With high expectations, many ongoing clinical trials are investigating the safety and efficacy of MSC therapies to treat arthritic diseases. Studies on osteoarthritis (OA) have shown positive clinical outcomes, with improved joint function, pain level, and quality of life. In addition, few clinical MSC trials conducted on rheumatoid arthritis (RA) patients have also displayed some optimistic outlook. The largely positive outcomes in clinical trials without severe side effects establish MSCs as promising tools for arthritis treatment. However, further research is required to investigate its applicability in clinical settings. This review discusses the most recent advances in clinical studies on MSC therapies for OA and RA.

Clinical and Radiological Changes after Microfracture of Knee Chondral Lesions in Middle-Aged Asian Patients

Background

Although microfracture is widely accepted as an effective treatment option for knee chondral lesions, little is known about the deterioration of clinical outcomes and radiological progression in middle-aged patients. Therefore, this study was conducted to evaluate the clinical and radiological changes after microfracture of knee chondral lesions in middle-aged Asian patients.

Methods

A total of 71 patients were included in the study. They were between the ages of 40 and 60 years and underwent arthroscopic microfracture for localized full-thickness cartilage defects of the knee from January 2000 to September 2015. The recovery status of chondral lesions was assessed by using the magnetic resonance observation of cartilage repair tissue (MOCART) score in postoperative magnetic resonance imaging (MRI). Clinical and radiological results were reviewed, and survival rate with conversion to arthroplasty or osteotomy as an end point was evaluated.

Results

The mean age of the patients at surgery was 51.3 ± 4.7 years (range, 40 to 60 years), and the mean follow-up period was 7.2 ± 2.6 years (range, 1.0 to 17.4 years). The MOCART scores of 32 patients at mean postoperative 2.1 years showed three cases (9%) of full recovery, two cases (7%) of hyperplastic recovery, 23 cases (70%) with more than 50% filling, and four cases (14%) with less than 50% filling. Clinical scores improved significantly at 1 year after surgery (p < 0.05); however, the scores deteriorated over time after postoperative 1 year, and the mean values reached preoperative levels at postoperative 10 years. Significant radiological progression of arthritis (Kellgren-Lawrence grade) was observed at 5 years after surgery. Four patients underwent total knee arthroplasty during follow-up.

Conclusions

Most patients showed more than 50% of defect filling at 2 years after surgery on MRI. Clinical results of microfracture of knee chondral lesion showed the best improvement at postoperative 1 year but gradually worsened thereafter until postoperative 10 years. Radiological progression of arthritis was observed from 5 years after surgery.

Emerging therapies for cartilage regeneration in currently excluded 'red knee' populations

The field of articular cartilage repair has made significant advances in recent decades; yet current therapies are generally not evaluated or tested, at the time of pivotal trial, in patients with a variety of common comorbidities. To that end, we systematically reviewed cartilage repair clinical trials to identify common exclusion criteria and reviewed the literature to identify emerging regenerative approaches that are poised to overcome these current exclusion criteria. The term “knee cartilage repair” was searched on clinicaltrials.gov. Of the 60 trials identified on initial search, 33 were further examined to extract exclusion criteria. Criteria excluded by more than half of the trials were identified in order to focus discussion on emerging regenerative strategies that might address these concerns. These criteria included age (<18 or >55 years old), small defects (<1 cm²), large defects (>8 cm²), multiple defect (>2 lesions), BMI >35, meniscectomy (>50%), bilateral knee pathology, ligamentous instability, arthritis, malalignment, prior repair, kissing lesions, neurologic disease of lower extremities, inflammation, infection, endocrine or metabolic disease, drug or alcohol abuse, pregnancy, and history of cancer. Finally, we describe emerging tissue engineering and regenerative approaches that might foster cartilage repair in these challenging environments. The identified criteria exclude a majority of the affected population from treatment, and thus greater focus must be placed on these emerging cartilage regeneration techniques to treat patients with the challenging “red knee”.

Functional outcomes after patellar autologous osteochondral transplantation

PURPOSE

The aim of the present study was to assess clinical evaluation of patients who underwent autologous osteochondral transplantation of the patella.

METHODS

This prospective study assessed outcomes of 20 patients who underwent patellar autologous osteochondral transplantation at four time-points: preoperatively, 3 days, 6 months, and 2 years after surgery. The following outcomes were assessed at each time-point: pain (VAS), gait, swelling, trophic status, muscle strength, patellar mobility, and range of motion. The Tegner scale was also applied for each time-point.

RESULTS

All parameters improved, except for patellar mobility, which did not show any change. Pain score decreased from 7.1 (SD 2.3) to 2.4 (SD 2.6) at the 2-year assessment; limping decreased from 70 % before surgery to 15 % 2 years later; swelling scores decreased from an average of 1.8 (SD 0.8) 3 days after surgery to 0.5 (SD 0.7) at the 2-year assessment; muscle strength increased from 3.9 (SD 0.8) to 4.7 (SD 0.7) points at final follow-up; and the range of motion increased from 84 (SD 16.2) to 132 (SD 10.7) degrees 2 years later. Tegner score before surgery ranged from 0 to 5, and after 2 years, it ranged from 5 to 9.

CONCLUSION

Autologous osteochondral transplantation for the treatment of patellar chondral lesion was associated with significant improvement in pain, gait, swelling, and range of motion 2 years after surgery, achieving scores similar to uninjured knees. Most of them were able to return to sports activity after 6 months (recreational level) and 2 years (competitive level).

LEVEL OF EVIDENCE

IV.

Incidence of knee cartilage surgery in Norway, 2008-2011

OBJECTIVE

A systematic and long-term data collection on the treatment of focal cartilage defects (FCDs) of the knee is needed. This can be achieved through the foundation of a National Knee Cartilage Defect Registry. The aim of this study was to establish the nationwide burden of knee cartilage surgery, defined as knee surgery in patients with an FCD. We also aimed to identify any geographical differences in incidence rates, patient demographics or trends within this type of surgery.

SETTING

A population-based study with retrospective identification of patients undergoing knee cartilage surgery in Norway through a mandatory public health database from 2008 to 2011.

PARTICIPANTS

We identified all patients undergoing cartilage surgery, or other knee surgery in patients with an FCD. All eligible surgeries were assessed for inclusion on the basis of certain types of ICD-10 and NOMESKO Classification of Surgical Procedures codes.

PRIMARY AND SECONDARY OUTCOME MEASURES

The variables were diagnostic and surgical codes, geographic location of the performing hospital, age and sex of the patients. Yearly incidence and incidence rates were calculated. Age-adjusted incidences for risk ratios and ORs between geographical areas were also calculated.

RESULTS

A total of 10,830 cases of knee cartilage surgery were identified, with slight but significant decreases from 2008 to 2011 (p<0.0003). The national incidence rate was 56/100 000 inhabitants and varied between regions, counties and hospitals. More than 50% of the procedures were palliative and nearly 400 yearly procedures were reparative or restorative.

CONCLUSIONS

Knee cartilage surgery is common in Norway, counting 2500 annual cases with an age-adjusted incidence rate of 68.8/100,000 inhabitants. There are significant geographical variations in incidence and trends of surgery and in trends between public and private hospitals. We suggest that a national surveillance system would be beneficial for the future evaluation of the treatment of these patients.

Large regional differences in incidence of arthroscopic meniscal procedures in the public and private sector in Denmark

OBJECTIVES

A recent study reported a large increase in the number of meniscal procedures from 2000 to 2011 in Denmark. We examined the nation-wide distribution of meniscal procedures performed in the private and public sector in Denmark since different incentives may be present and the use of these procedures may differ from region to region.

SETTING

We included data on all patients who underwent an arthroscopic meniscal procedure performed in the public or private sector in Denmark.

PARTICIPANTS

Data were retrieved from the Danish National Patient Register on patients who underwent arthroscopic meniscus surgery as a primary or secondary procedure in the years 2000 to 2011. Hospital identification codes enabled linkage of performed procedures to specific hospitals.

PRIMARY AND SECONDARY OUTCOME MEASURES

Yearly incidence of meniscal procedures per 100,000 inhabitants was calculated with 95% CIs for public and private procedures for each region.

RESULTS

Incidence of meniscal procedures increased at private and at public hospitals. The private sector accounted for the largest relative and absolute increase, rising from an incidence of 1 in 2000 to 98 in 2011. In 2011, the incidence of meniscal procedures was three times higher in the Capital Region than in Region Zealand.

CONCLUSIONS

Our study identified a large increase in the use of meniscal procedures in the public and private sector in Denmark. The increase was particularly conspicuous in the private sector as its proportion of procedures performed increased from 1% to 32%. Substantial regional differences were present in the incidence and trend over time of meniscal procedures.