Previous cartilage surgery is associated with inferior patient-reported outcomes after knee arthroplasty

PURPOSE

The hypothesis of the present study assumed that a history of focal cartilage lesions would not affect Knee Injury and Osteoarthritis Outcome scores (KOOSs) following knee arthroplasty compared to a matched national cohort of knee arthroplasty patients.

METHODS

Fifty-eight knee arthroplasty patients with previous surgery for focal cartilage lesions (cartilage cohort) were compared to a matched cohort of 116 knee arthroplasty patients from the Norwegian Arthroplasty Register (control group). Age, sex, primary or revision arthroplasty, type of arthroplasty (total, unicondylar or patellofemoral), year of arthroplasty surgery and arthroplasty brand were used as matching criteria. Demographic data and KOOS were obtained through questionnaires. Regression models were employed to adjust for confounding factors.

RESULTS

Mean follow-up post knee arthroplasty surgery was 7.6 years (range 1.2-20.3) in the cartilage cohort and 8.1 (range 1.0-20.9) in the control group. The responding patients were at the time of surgery 54.3 versus 59.0 years in the cartilage and control group, respectively. At follow-up the control group demonstrated higher adjusted Knee Injury and Osteoarthritis Outcome subscores than the previous focal cartilage patients with a mean adjusted difference (95% confidence interval in parentheses): Symptoms 8.4 (0.3, 16.4), Pain 11.8 (2.2, 21.4), Activities of daily living (ADL) 9.3 (-1.2, 18.6), Sport and recreation 8.9 (-1.6, 19.4) and Quality of Life (QoL) 10.6 (0.2, 21.1). The control group also demonstrated higher odds of reaching the patient-acceptable symptom state threshold for the Knee Injury and Osteoarthritis Outcome subscores with odds ratio: Symptoms 2.7 (1.2, 6.4), Pain 3.0 (1.3, 7.0), ADL 2.1 (0.9, 4.6) and QoL 2.4 (1.0, 5.5).

CONCLUSION

Previous cartilage surgery was associated with inferior patient-reported outcomes after knee arthroplasty. These patients also exhibited significantly lower odds of reaching the patient-acceptable symptom state threshold for the Knee Injury and Osteoarthritis Outcome subscores.

LEVEL OF EVIDENCE

Level III.

The Long-Term Risk of Knee Arthroplasty in Patients with Arthroscopically Verified Focal Cartilage Lesions: A Linkage Study with the Norwegian Arthroplasty Register, 1999 to 2020

BACKGROUND

Focal cartilage lesions are common in the knee. The risk of later ipsilateral knee arthroplasty remains unknown. The purposes of the present study were to evaluate the long-term cumulative risk of knee arthroplasty after arthroscopic identification of focal cartilage lesions in the knee, to investigate the risk factors for subsequent knee arthroplasty, and to estimate the subsequent cumulative risk of knee arthroplasty compared with that in the general population.

METHODS

Patients who had undergone surgical treatment of focal cartilage lesions at 6 major Norwegian hospitals between 1999 and 2012 were identified. The inclusion criteria were an arthroscopically classified focal cartilage lesion in the knee, an age of ≥18 years at the time of surgery, and available preoperative patient-reported outcomes (PROMs). The exclusion criteria were osteoarthritis or "kissing lesions" at the time of surgery. Demographic data, later knee surgery, and PROMs were collected with use of a questionnaire. A Cox regression model was used to adjust for and investigate the impact of risk factors, and Kaplan-Meier analysis was performed to estimate cumulative risk. The risk of knee arthroplasty in the present cohort was compared with that in the age-matched general Norwegian population.

RESULTS

Of the 516 patients who were eligible, 322 patients (328 knees) consented to participate. The mean age at the time of the index procedure was 36.8 years, and the mean duration of follow-up was 19.8 years. The 20-year cumulative risk of knee arthroplasty in the cartilage cohort was 19.1% (95% CI, 14.6% to 23.6%). Variables that had an impact on the risk of knee arthroplasty included an ICRS grade of 3 to 4 (hazard ratio [HR], 3.1; 95% CI, 1.1 to 8.7), an age of ≥40 years at time of cartilage surgery (HR, 3.7; 95% CI, 1.8 to 7.7), a BMI of 25 to 29 kg/m2 (HR, 3.9; 95% CI, 1.7 to 9.0), a BMI of ≥30 kg/m2 (HR, 5.9; 95% CI, 2.4 to 14.3) at the time of follow-up, autologous chondrocyte implantation (ACI) at the time of the index procedure (HR, 3.4; 95% CI, 1.0 to 11.4), >1 focal cartilage lesion (HR, 2.1; 95% CI, 1.1 to 3.7), and a high preoperative visual analog scale (VAS) score for pain at the time of the index procedure (HR, 1.1; 95% CI, 1.0 to 1.1). The risk ratio of later knee arthroplasty in the cartilage cohort as compared with the age-matched general Norwegian population was 415.7 (95% CI, 168.8 to 1,023.5) in the 30 to 39-year age group.

CONCLUSIONS

In the present study, we found that the 20-year cumulative risk of knee arthroplasty after a focal cartilage lesion in the knee was 19%. Deep lesions, higher age at the time of cartilage surgery, high BMI at the time of follow-up, ACI, and >1 cartilage lesion were associated with a higher risk of knee arthroplasty.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A Randomized Trial of Autologous Chondrocyte Implantation Versus Alternative Forms of Surgical Cartilage Management in Patients With a Failed Primary Treatment for Chondral or Osteochondral Defects in the Knee

BACKGROUND

There are limited randomized controlled trials with long-term outcomes comparing autologous chondrocyte implantation (ACI) versus alternative forms of surgical cartilage management within the knee.

PURPOSE

To determine at 5 years after surgery whether ACI was superior to alternative forms of cartilage management in patients after a failed previous treatment for chondral or osteochondral defects in the knee.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

In total, 390 participants were randomly assigned to receive either ACI or alternative management. Patients aged 18 to 55 years with one or two symptomatic cartilage defects who had failed 1 previous therapeutic surgical procedure in excess of 6 months prior were included. Dual primary outcome measures were used: (1) patient-completed Lysholm knee score and (2) time from surgery to cessation of treatment benefit. Secondary outcome measures included International Knee Documentation Committee and Cincinnati Knee Rating System scores, as well as number of serious adverse events. Analysis was performed on an intention-to-treat basis.

RESULTS

Lysholm scores were improved by 1 year in both groups (15.4 points [95% CI, 11.9 to 18.8] and 15.2 points [95% CI, 11.6 to 18.9]) for ACI and alternative, with this improvement sustained over the duration of the trial. However, no evidence of a difference was found between the groups at 5 years (2.9 points; 95% CI, -1.8 to 7.5; P = .46). Approximately half of the participants (55%; 95% CI, 47% to 64% with ACI) were still experiencing benefit at 5 years, with time to cessation of treatment benefit similar in both groups (hazard ratio, 0.97; 95% CI, 0.72 to 1.32; P > .99). There was a differential effect on Lysholm scores in patients without previous marrow stimulation compared with those with marrow stimulation (P = .03; 6.4 points in favor of ACI; 95% CI, -0.4 to 13.1). More participants experienced a serious adverse event with ACI (P = .02).

CONCLUSION

Over 5 years, there was no evidence of a difference in Lysholm scores between ACI and alternative management in patients who had previously failed treatment. Previous marrow stimulation had a detrimental effect on the outcome of ACI.

REGISTRATION

International Standard Randomised Controlled Trial Number: 48911177.

Collagen-Covered Autologous Chondrocyte Implantation Versus Autologous Matrix-Induced Chondrogenesis: A Randomized Trial Comparing 2 Methods for Repair of Cartilage Defects of the Knee

Background:

Autologous matrix-induced chondrogenesis (AMIC) is a single-stage alternative to autologous chondrocyte implantation for treatment of localized cartilage defects of the knee. To our knowledge, no randomized controlled trial exists comparing the 2 methods.

Purpose:

To evaluate any difference in the outcome of AMIC as compared with collagen-covered autologous chondrocyte implantation (ACI-C).

Study Design:

Randomized controlled trial; Level of evidence, 2.

Methods:

A prospective randomized controlled clinical trial was designed to assess any differences in the outcomes between ACI-C and AMIC for the treatment of ≥1 chondral or osteochondral defects of the distal femur and/or patella. The inclusion period was set to 3 years, and the aim was to include 80 patients (40 in each group). Patient inclusion was broad, with few exclusion criteria. The primary outcome was change in Knee injury and Osteoarthritis Outcome Score (KOOS) at 2 years as compared with baseline. The secondary outcomes were the number of failures in each group at 2 years and the change in KOOS subscale, Lysholm, and pain visual analog scale (VAS) scores at 2 years as compared with baseline. A 2-sample t test with a significance level of P < .05 was used to compare the change in score from baseline between groups.

Results:

A total of 41 patients over 3 years were included in the study: 21 in the ACI-C group and 20 in the AMIC group. All the patients had prior surgery to the index knee. At 2-year follow-up, the clinical scores for both groups improved significantly from baseline. No significant differences between groups were seen in the change from baseline for KOOS (AMIC, 18.1; ACI-C, 10.3), any of the KOOS subscales, the Lysholm score (AMIC, 19.7; ACI-C, 17.0), or the VAS pain score (AMIC, 30.6; ACI-C, 19.6). Two patients in the AMIC group had progressed to a total knee replacement by the 2-year follow-up as compared with none in the ACI-C group.

Conclusion:

At 2-year follow-up, no significant differences were found regarding outcomes between ACI-C and AMIC. Mid- and long-term results will be important.

Registration:

NCT01458782 (ClinicalTrials.gov identifier).

In vitro chondrogenic potency of surplus chondrocytes from autologous transplantation procedures does not predict short-term clinical outcomes

BACKGROUND

Autologous chondrocyte implantation (ACI) has been used over the last two decades to treat focal cartilage lesions aiming to delay or prevent the onset of osteoarthritis; however, some patients do not respond adequately to the procedure. A number of biomarkers that can forecast the clinical potency of the cells have been proposed, but evidence for the relationship between in vitro chondrogenic potential and clinical outcomes is missing. In this study, we explored if the ability of cells to make cartilage in vitro correlates with ACI clinical outcomes. Additionally, we evaluated previously proposed chondrogenic biomarkers and searched for new biomarkers in the chondrocyte proteome capable of predicting clinical success or failure after ACI.

METHODS

The chondrogenic capacity of chondrocytes derived from 14 different donors was defined based on proteoglycans staining and visual histological grading of tissues generated using the pellet culture system. A Lysholm score of 65 two years post-ACI was used as a cut-off to categorise "success" and "failure" clinical groups. A set of predefined biomarkers were investigated in the chondrogenic and clinical outcomes groups using flow cytometry and qPCR. High-throughput proteomics of cell lysates was used to search for putative biomarkers to predict chondrogenesis and clinical outcomes.

RESULTS

Visual histological grading of pellets categorised donors into "high" and "low" chondrogenic groups. Direct comparison between donor-matched in vitro chondrogenic potential and clinical outcomes revealed no significant associations. Comparative analyses of selected biomarkers revealed that expression of CD106 and TGF-β-receptor-3 was enhanced in the low chondrogenic group, while expression of integrin-α1 and integrin-β1 was significantly upregulated in the high chondrogenic group. Additionally, increased surface expression of CD166 was observed in the clinical success group, while the gene expression of cartilage oligomeric matrix protein was downregulated. High throughput proteomics revealed no differentially expressed proteins from success and failure clinical groups, whereas seven proteins including prolyl-4-hydroxylase 1 were differentially expressed when comparing chondrogenic groups.

CONCLUSION

In our limited material, we found no correlation between in vitro cartilage-forming capacity and clinical outcomes, and argue on the limitations of using the chondrogenic potential of cells or markers for chondrogenesis as predictors of clinical outcomes.

Patient reported outcomes with remote orthopaedic consultations by telemedicine: A randomised controlled trial

INTRODUCTION

Decentralised services through outreach clinics or modern technology reduce patient travel time and cost to society. Telemedicine consultation through videoconference is one such modality. Here, we compared patient-reported health outcomes and satisfaction between video-assisted remote and standard face-to-face orthopaedic consultations.

METHODS

This randomised controlled trial included two parallel groups: (1) patients receiving video-assisted remote consultation at a regional medical centre (RMC); and (2) patients receiving standard consultation at the orthopaedic outpatient clinic of the University Hospital of North Norway (UNN). This study included patients referred to or scheduled for a consultation at the orthopaedic outpatient clinic. After each consultation, patient satisfaction was determined using patient-completed questionnaires containing questions on patient-reported health (three-level European quality of life five-dimension index (EQ-5D-3L)/European quality of life visual analogue scale (EQ-VAS)) and questions from a validated OutPatient Experiences Questionnaire (OPEQ).

RESULTS

This study included 389 patients, of which 199 received remote consultation and 190 received standard consultation (total of 559 consultations). In all, 99% RMC-randomised patients and 99% UNN-randomised patients evaluated the consultation as very satisfactory or satisfactory. Moreover, 86% RMC-randomised patients preferred video-assisted consultation as the next consultation. No difference was observed in patient-reported health after 12 months between the two groups. EQ-5D index scores were 0.77 and 0.75 for RMC- and UNN-randomised patients, respectively (p = 0.42).

DISCUSSION

We did not observe any difference in patient-reported satisfaction and health (EQ-5D/EQ-VAS) between video-assisted and standard consultations, suggesting that video-assisted remote consultation can be safely offered to some orthopaedic patients. Moreover, a significantly high proportion of patients selected video-assisted remote consultation as their next consultation, thus strengthening the findings of this study. However, economic aspects should be assessed before widely recommending video-assisted consultation.

Patient reported outcomes with remote orthopaedic consultations by telemedicine: A randomised controlled trial

Introduction

Decentralised services through outreach clinics or modern technology reduce patient travel time and cost to society. Telemedicine consultation through videoconference is one such modality. Here, we compared patient-reported health outcomes and satisfaction between video-assisted remote and standard face-to-face orthopaedic consultations.

Methods

This randomised controlled trial included two parallel groups: (1) patients receiving video-assisted remote consultation at a regional medical centre (RMC); and (2) patients receiving standard consultation at the orthopaedic outpatient clinic of the University Hospital of North Norway (UNN). This study included patients referred to or scheduled for a consultation at the orthopaedic outpatient clinic. After each consultation, patient satisfaction was determined using patient-completed questionnaires containing questions on patient-reported health (three-level European quality of life five-dimension index (EQ-5D-3L)/European quality of life visual analogue scale (EQ-VAS)) and questions from a validated OutPatient Experiences Questionnaire (OPEQ).

Results

This study included 389 patients, of which 199 received remote consultation and 190 received standard consultation (total of 559 consultations). In all, 99% RMC-randomised patients and 99% UNN-randomised patients evaluated the consultation as very satisfactory or satisfactory. Moreover, 86% RMC-randomised patients preferred video-assisted consultation as the next consultation. No difference was observed in patient-reported health after 12 months between the two groups. EQ-5D index scores were 0.77 and 0.75 for RMC- and UNN-randomised patients, respectively ( p = 0.42).

Discussion

We did not observe any difference in patient-reported satisfaction and health (EQ-5D/EQ-VAS) between video-assisted and standard consultations, suggesting that video-assisted remote consultation can be safely offered to some orthopaedic patients. Moreover, a significantly high proportion of patients selected video-assisted remote consultation as their next consultation, thus strengthening the findings of this study. However, economic aspects should be assessed before widely recommending video-assisted consultation.

Quality of care for remote orthopaedic consultations using telemedicine: a randomised controlled trial

Background

Decentralised services using outreach clinics or modern technology are methods to reduce both patient transports and costs to the healthcare system. Telemedicine consultations via videoconference are one such modality. Before new technologies are implemented, it is important to investigate both the quality of care given and the economic impact from the use of this new technology. The aim of this clinical trial was to study the quality of planned remote orthopaedic consultations by help of videoconference.

Method

We performed a randomised controlled trial (RCT) with two parallel groups: video-assisted remote consultations at a regional medical centre (RMC) as an intervention versus standard consultation in the orthopaedic outpatient clinic at the University Hospital of North Norway (UNN) as a control. The participants were patients referred to or scheduled for a consultation at the orthopaedic outpatient clinic. The orthopaedic surgeons evaluated each consultation they performed by completing a questionnaire. The primary outcome measurement was the difference in the sum score calculated from this questionnaire, which was evaluated by the non-inferiority of the intervention group. The study design was based on the intention to treat principle. Ancillary analyses regarding complications, the number of consultations per patient, operations, patients who were referred again and the duration of consultations were performed.

Results

Four-hundred patients were web-based randomised. Of these, 199 (98 %) underwent remote consultation and 190 (95 %) underwent standard consultation. The primary outcome, the sum score of the specialist evaluation, was significantly lower (i.e. ‘better’) at UNN compared to RMC (1.72 versus 1.82, p = 0.0030). The 90 % confidence interval (CI) for the difference in score (0.05, 0.17) was within the non-inferiority margin. The orthopaedic surgeons involved evaluated 98 % of the video-assisted consultations as ‘good’ or ‘very good’. In the ancillary analyses, there was no significant difference between the two groups.

Conclusions

This study supports the argument that it is safe to offer video-assisted consultations for selected orthopaedic patients. We did not find any serious events related to the mode of consultation. Further assessments of the economic aspects and patient satisfaction are needed before we can recommend its wider application.

Trial registration

ClinicalTrials.gov identifier: NCT00616837

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-016-1717-7) contains supplementary material, which is available to authorized users.

Quality of care for remote orthopaedic consultations using telemedicine: a randomised controlled trial

BACKGROUND

Decentralised services using outreach clinics or modern technology are methods to reduce both patient transports and costs to the healthcare system. Telemedicine consultations via videoconference are one such modality. Before new technologies are implemented, it is important to investigate both the quality of care given and the economic impact from the use of this new technology. The aim of this clinical trial was to study the quality of planned remote orthopaedic consultations by help of videoconference.

METHOD

We performed a randomised controlled trial (RCT) with two parallel groups: video-assisted remote consultations at a regional medical centre (RMC) as an intervention versus standard consultation in the orthopaedic outpatient clinic at the University Hospital of North Norway (UNN) as a control. The participants were patients referred to or scheduled for a consultation at the orthopaedic outpatient clinic. The orthopaedic surgeons evaluated each consultation they performed by completing a questionnaire. The primary outcome measurement was the difference in the sum score calculated from this questionnaire, which was evaluated by the non-inferiority of the intervention group. The study design was based on the intention to treat principle. Ancillary analyses regarding complications, the number of consultations per patient, operations, patients who were referred again and the duration of consultations were performed.

RESULTS

Four-hundred patients were web-based randomised. Of these, 199 (98 %) underwent remote consultation and 190 (95 %) underwent standard consultation. The primary outcome, the sum score of the specialist evaluation, was significantly lower (i.e. 'better') at UNN compared to RMC (1.72 versus 1.82, p = 0.0030). The 90 % confidence interval (CI) for the difference in score (0.05, 0.17) was within the non-inferiority margin. The orthopaedic surgeons involved evaluated 98 % of the video-assisted consultations as 'good' or 'very good'. In the ancillary analyses, there was no significant difference between the two groups.

CONCLUSIONS

This study supports the argument that it is safe to offer video-assisted consultations for selected orthopaedic patients. We did not find any serious events related to the mode of consultation. Further assessments of the economic aspects and patient satisfaction are needed before we can recommend its wider application.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00616837.

A Randomized Multicenter Trial Comparing Autologous Chondrocyte Implantation with Microfracture: Long-Term Follow-up at 14 to 15 Years

BACKGROUND

The management of cartilage and osteochondral lesions in the knee remains problematic and controversial. Our group reported the 2-year and 5-year results of a randomized controlled trial comparing autologous chondrocyte implantation (ACI) and microfracture in patients with focal femoral cartilage injuries. The objective of the present study was to report the long-term results.

METHODS

Eighty patients with a single symptomatic chronic cartilage defect on the femoral condyle without general osteoarthritis were included in the study at the time of the index operation (January 1999 to February 2000). We used the International Cartilage Repair Society (ICRS), Lysholm, Short Form-36 (SF-36), and Tegner forms to collect data at the time of inclusion and at follow-up evaluations. Standing weight-bearing radiographs were evaluated for evidence of osteoarthritis according to the method described by Kellgren and Lawrence. For the long-term follow-up in 2014, we used the Synaflexer frame to standardize the radiographs. The operation was considered to have failed if a reoperation was performed because of symptoms from a lack of healing of the treated defect.

RESULTS

At the long-term follow-up evaluation, no significant differences between the treatment groups were detected with respect to the results on the clinical scoring systems. At the 15-year evaluation, there were 17 failures in the ACI group compared with 13 in the microfracture group. We observed that more total knee replacements were needed in the ACI group than in the microfracture group (6 compared with 3). The surviving patients in both groups, i.e., those who had not had a failure, had significant improvement in the clinical scores compared with baseline. Fifty-seven percent of the surviving patients in the ACI group and 48% of such patients in the microfracture group had radiographic evidence of early osteoarthritis (a Kellgren and Lawrence grade of ≥2); the difference was not significant.

CONCLUSIONS

The survivors in both groups improved their clinical scores in the short, medium, and long-term evaluations, and no significant difference between the groups was found at the long-term follow-up. The risk of treatment failure and the frequency of radiographic osteoarthritis are problematic. Our findings raise serious concerns regarding the efficacy of these procedures in delaying osteoarthritis and preventing further surgery. Continued basic and clinical research is needed in this field.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Cartilage repair and joint preservation: medical and surgical treatment options

BACKGROUND

Articular cartilage defects are most often caused by trauma and osteoarthritis and less commonly by metabolic disorders of the subchondral bone, such as osteonecrosis and osteochondritis dissecans. Such defects do not heal spontaneously in adults and can lead to secondary osteoarthritis. Medications are indicated for symptomatic relief. Slow-acting drugs in osteoarthritis (SADOA), such as glucosamine and chondroitin, are thought to prevent cartilage degeneration. Reconstructive surgical treatment strategies aim to form a repair tissue or to unload compartments of the joint with articular cartilage damage.

METHODS

In this article, we selectively review the pertinent literature, focusing on original publications of the past 5 years and older standard texts. Particular attention is paid to guidelines and clinical studies with a high level of evidence, along with review articles, clinical trials, and book chapters.

RESULTS

There have been only a few randomized trials of medical versus surgical treatments. Pharmacological therapies are now available that are intended to treat the cartilage defect per se, rather than the associated symptoms, yet none of them has yet been shown to slow or reverse the progression of cartilage destruction. Surgical débridement of cartilage does not prevent the progression of osteoarthritis and is thus not recommended as the sole treatment. Marrow-stimulating procedures and osteochondral grafts are indicated for small focal articular cartilage defects, while autologous chondrocyte implantationis mainly indicated for larger cartilage defects. These surgical reconstructive techniques play a lesser role in the treatment of osteoarthritis. Osteotomy near the knee joint is indicated for axial realignment when unilateral osteoarthritis of the knee causes axis deviation.

CONCLUSION

Surgical reconstructive techniques can improve joint function and thereby postpone the need for replacement of the articular surface with an artificial joint.

A new histology scoring system for the assessment of the quality of human cartilage repair: ICRS II

BACKGROUND

A reliable and reproducible method is needed to assess cartilage repair.

PURPOSE

This study was undertaken to test the reproducibility of 2 established histological scoring systems, the Modified O'Driscoll Scale (MODS) and International Cartilage Research Society (ICRS) Visual Assessment Scale (ICRS I), and subsequently to develop and evaluate a new grading system for cartilage repair.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A total of 107 cartilage biopsy specimens were graded using MODS and ICRS I, and the reader variability was measured. The new grading system, ICRS II, was developed and the inter- and intrareader variability determined by 3 independent readers. Collagen type II deposition was assessed immunohistochemically.

RESULTS

The MODS and ICRS I demonstrated high interreader variability, with MODS also showing high intrareader variability. A new histological scoring system, ICRS II, was developed comprising 14 criteria to assess parameters related to chondrocyte phenotype and tissue structure. The ICRS II demonstrated lower inter- and intrareader variability compared with MODS or ICRS I. The overall assessment and matrix staining scores had the best correlation coefficients for inter- and intrareader variability (r = .81 and .82, respectively). The extent of collagen type II in cartilage, considered a marker of differentiation toward hyaline cartilage, could represent a measure of good cartilage repair. A correlation coefficient of .56 was obtained between the extent of collagen type II staining and the overall assessment score.

CONCLUSION

The ICRS II represents an improvement over current histological cartilage repair grading systems in terms of reader reproducibility. The clinical relevance and its ability to predict long-term repair durability will be assessed once long-term clinical data become available.

The subchondral bone in articular cartilage repair: current problems in the surgical management

As the understanding of interactions between articular cartilage and subchondral bone continues to evolve, increased attention is being directed at treatment options for the entire osteochondral unit, rather than focusing on the articular surface only. It is becoming apparent that without support from an intact subchondral bed, any treatment of the surface chondral lesion is likely to fail. This article reviews issues affecting the entire osteochondral unit, such as subchondral changes after marrow-stimulation techniques and meniscectomy or large osteochondral defects created by prosthetic resurfacing techniques. Also discussed are surgical techniques designed to address these issues, including the use of osteochondral allografts, autologous bone grafting, next generation cell-based implants, as well as strategies after failed subchondral repair and problems specific to the ankle joint. Lastly, since this area remains in constant evolution, the requirements for prospective studies needed to evaluate these emerging technologies will be reviewed.

Elevated plasma beta-endorphin/beta-lipotropin concentration following a radius fracture

Plasma beta-endorphin/beta-lipotropin concentration was assessed soon after a fracture. Blood samples from 14 patients with radius fractures were obtained from both arms soon after admission to the hospital (mean 245 min) after the accident. Follow-up samples were taken after healing of the fractures. Higher plasma beta-endorphin/beta-lipotropin concentrations were found in blood samples taken soon after a fracture in both arms compared with the concentrations after healing of the fracture. At admission, mean beta-endorphin/beta-lipotropin concentrations in the fractured and the contralateral arms were 12.7 pmol/L and 13.2 pmol/L, and after recovery 11.1 pmol/L and 11.5 pmol/L (p = 0.012 and p = 0.041), respectively. The pain decreased according to the visual analogue scale (VAS) (0-10) from 4.64 at admission to 0.58 after healing (p < 0.001). In conclusion, this study showed that beta-endorphin/beta-lipotropin concentrations are increased in both arms following a radius fracture compared to the level after the fracture has healed.

Development of a new method to harvest chondroprogenitor cells from underneath cartilage defects in the knees

BACKGROUND

Mesenchymal progenitor cells from bone marrow hold great potential as a cell source for cartilage repair. Aspiration from the iliac crest is the most widely used method to harvest bone marrow cells for cartilage repair. The objective of our study was to establish a new method to isolate mesenchymal progenitor cells by direct aspiration of bone marrow from the subchondral spongious bone underneath cartilage defects during microfracture treatment and to confirm the chondrogenic potential of the resulting cell cultures.

METHODS

Bone marrow was aspirated arthroscopically from patients treated for isolated cartilage defects. Adherent stromal cells were isolated, expanded in monolayer cultures, and characterized by flow cytometry. Chondrogenic induction of cells was achieved by combination of spheroid cultures in hanging drops and the concomitant use of transforming growth factor-beta (TGFbeta). Articular chondrocytes established in three-dimensional (3D) cultures were used as positive cartilage-forming units, and skin fibroblasts were used as negative controls. Three-dimensional constructs were stained for immunohistochemical and histological examination, and a real-time polymerase chain reaction (PCR) was performed to quantify the expression of aggrecan, collagen types 1 and 2, and Sox9.

RESULTS

Mesenchymal stem cell-like progenitor cells (MSCs) displaying chondrogenic differentiation capacity were harvested arthroscopically from underneath cartilage lesions on distal femurs using the one-hole technique. Stem cell-related surface antigens analyzed by flow cytometry confirmed the nature of the isolated adherent cells. MSC spheroids stained positive for glycosaminoglycans and collagen type 2. Realtime PCR showed that MSCs in 3D spheroids significantly increased gene expression of collagen type 2, aggrecan, and Sox 9 and down-regulated expression of collagen type 1 when compared to the mRNA levels measured in MSCs monolayers.

CONCLUSIONS

We describe a new technique that may be applied for harvesting bone marrow cells from cartilage defects during arthroscopic intervention of the knee. Cells harvested in this way hold full chondrogenic differentiation potential. Our data imply that MSC storage may be established by using marrow from this approach, bypassing the need for cell aspiration from the iliac crest.

Beta-endorphin regulation of MAPKs in cultured human articular chondrocytes: MAPK inhibitors prevent the increase of IL-1 beta protein levels during beta-endorphin stimulation

We investigated the effect of beta-endorphin on the activities of mitogen-activated protein kinases in cultured human articular chondrocytes in order to elucidate its effect on cartilage. Monolayer cultures of chondrocytes obtained from patients undergoing total knee arthroplasty were treated with 60, 600, or 6000 ng/ml beta-endorphin, or 100 ng/ml naltrexone combined with 600 ng/ml beta-endorphin. The regulation of three major mitogen-activated protein kinases phosphorylation, ERKp44/p42, p38, and JNK, was determined by Western blotting. We also examined the influence of specific mitogen-activated protein kinase inhibitors on IL-1 beta protein levels during beta-endorphin stimulation. The results demonstrate that beta-endorphin, dependent on concentration and duration of stimulation, significantly affected the activation of the three mitogen-activated protein kinases in cultured human articular chondrocytes. Naltrexone in some cases significantly regulated the mitogen-activated protein kinases in different ways when added to beta-endorphin 600 ng/ml. Furthermore, specific mitogen-activated protein kinase inhibitors hindered the increase of IL-1 beta during beta-endorphin incubation. The effect of beta-endorphin seen in this study is considered critical for the production of several mediators of cartilage damage in an arthritic joint.

A randomized trial comparing autologous chondrocyte implantation with microfracture. Findings at five years

BACKGROUND

The optimal treatment for cartilage lesions has not yet been established. The objective of this randomized trial was to compare autologous chondrocyte implantation with microfracture. This paper represents an update, with presentation of the clinical results at five years.

METHODS

Eighty patients who had a single chronic symptomatic cartilage defect on the femoral condyle in a stable knee without general osteoarthritis were included in the study. Forty patients were treated with autologous chondrocyte implantation, and forty were treated with microfracture. We used the International Cartilage Repair Society, Lysholm, Short Form-36, and Tegner forms to collect clinical data, and radiographs were evaluated with use of the Kellgren and Lawrence grading system.

RESULTS

At two and five years, both groups had significant clinical improvement compared with the preoperative status. At the five-year follow-up interval, there were nine failures (23%) in both groups compared with two failures of the autologous chondrocyte implantation and one failure of the microfracture treatment at two years. Younger patients did better in both groups. We did not find a correlation between histological quality and clinical outcome. However, none of the patients with the best-quality cartilage (predominantly hyaline) at the two-year mark had a later failure. One-third of the patients in both groups had radiographic evidence of early osteoarthritis at five years.

CONCLUSIONS

Both methods provided satisfactory results in 77% of the patients at five years. There was no significant difference in the clinical and radiographic results between the two treatment groups and no correlation between the histological findings and the clinical outcome. One-third of the patients had early radiographic signs of osteoarthritis five years after the surgery. Further long-term follow-up is needed to determine if one method is better than the other and to study the progression of osteoarthritis.

Detection of mRNA transcripts of truncated opiate precursor (POMC) in human cartilage

In the present study, we have investigated the presence of pro-opiomelanocortin C-terminal fragment derived-peptides in human articular cartilage and cultured chondrocytes. beta-Lipotropin and beta-endorphin were monitored in different cell cultures and biopsies using different techniques. Biopsies were taken from patients undergoing total knee arthroplasty due to osteoarthritis. Both fresh tissue sections and chondrocytes cultured in monolayer were used in the study. Immunohistochemistry, immunocytochemistry, reverse transcriptase-polymerase chain reaction and qualitative Western blots were carried out. The results of the reverse transcriptase-polymerase chain reaction showed transcription of a truncated-form of mRNA for pro-opiomelanocortin in native cartilage and cultured chondrocytes. There was no detection of endogenous production of beta-lipotropin or beta-endorphin in human articular chondrocytes, either in situ or in vitro. Whether pro-opiomelanocortin-derived peptides of non-cartilaginous origin are present in articular cartilage itself still remains unclear.

Arthroscopic assessment of cartilage repair: a validation study of 2 scoring systems

PURPOSE

This study tested the validity and reliability of the International Cartilage Repair Society (ICRS) cartilage repair assessment and the Oswestry Arthroscopy Score (OAS), which have been designed to assess repair of articular cartilage.

TYPE OF STUDY

Prospective validation study of arthroscopic cartilage repair scores.

METHODS

Arthroscopic videos were assessed by a panel of orthopaedic surgeons specializing in cartilage repair. Scoring was repeated after a 2-month interval. Scorers also answered a questionnaire to assess the face and content validity of the scoring systems. Validity of the 2 systems was compared and reliability and repeatability were measured. Pearson's correlation coefficient was used to measure equivalence reliability. The interclass correlation coefficient (ICC) was used to assess the repeatability and inter-rater reliability of each score, and internal consistency was assessed with Cronbach's alpha.

RESULTS

Face and content validity are acceptable for both scores. There is good agreement (equivalence reliability) between the scores (Pearson's correlation coefficient, r = .88; P < .001). Stability (interobserver reliability) and repeatability (test-retest reliability) are satisfactory for both scores with an ICC >0.7 for each score. Cronbach's alpha was 0.91 for ICRS and 0.82 for OAS, indicating better internal consistency for the ICRS score.

CONCLUSIONS

The ICRS and OAS arthroscopic scores have been validated for the assessment of cartilage repair and both have been found to be statistically reliable and repeatable. The ICRS score does not allow for graft hypertrophy and may overscore in this situation, whereas the OAS includes assessment of graft stiffness. Both scores show satisfactory stability and repeatability. Internal consistency is adequate for both scores, although it is higher for the ICRS score. Both the ICRS and OAS arthroscopic scores are effective tools in the evaluation of cartilage repair.

LEVEL OF EVIDENCE

Level III, diagnostic study of nonconsecutive patients (no consistently applied reference gold standard).

Autologous chondrocyte implantation compared with microfracture in the knee. A randomized trial

BACKGROUND

New methods have been used, with promising results, to treat full-thickness cartilage defects. The objective of the present study was to compare autologous chondrocyte implantation with microfracture in a randomized trial. We are not aware of any previous randomized studies comparing these methods.

METHODS

Eighty patients without general osteoarthritis who had a single symptomatic cartilage defect on the femoral condyle in a stable knee were treated with autologous chondrocyte implantation or microfracture (forty in each group). We used the International Cartilage Repair Society, Lysholm, Short Form-36 (SF-36), and Tegner forms to collect data. An independent observer performed a follow-up examination at twelve and twenty-four months. Two years postoperatively, arthroscopy with biopsy for histological evaluation was carried out. The histological evaluation was done by a pathologist and a clinical scientist, both of whom were blinded to each patient's treatment.

RESULTS

In general, there were small differences between the two treatment groups. At two years, both groups had significant clinical improvement. According to the SF-36 physical component score at two years postoperatively, the improvement in the microfracture group was significantly better than that in the autologous chondrocyte implantation group (p = 0.004). Younger and more active patients did better in both groups. There were two failures in the autologous chondrocyte implantation group and one in the microfracture group. No serious complications were reported. Biopsy specimens were obtained from 84% of the patients, and histological evaluation of repair tissues showed no significant differences between the two groups. We did not find any association between the histological quality of the tissue and the clinical outcome according to the scores on the Lysholm or SF-36 form or the visual analog scale.

CONCLUSIONS

Both methods had acceptable short-term clinical results. There was no significant difference in macroscopic or histological results between the two treatment groups and no association between the histological findings and the clinical outcome at the two-year time-point.

LEVEL OF EVIDENCE

Therapeutic study, Level I-1a (randomized controlled trial [significant difference]). See Instructions to Authors for a complete description of levels of evidence.

Prevalence of Salmonella typhimurium infection in Norwegian hedgehog populations associated with two human disease outbreaks

Faecal carriage of salmonella was investigated in 320 hedgehogs from Moss municipality in south-eastern Norway, Askøy, Bergen and Os municipalities in central-western Norway, and five municipalities in south-western and central Norway. The sampling in Moss was carried out 1 year after a human outbreak of salmonellosis, whereas the sampling in Askøy, Bergen and Os was carried out during a human outbreak. Both outbreaks were caused by Salmonella Typhimurium 4,5,12:i:1,2. No salmonella were detected in the hedgehogs from south-western (0/115) and central (0/24) Norway. Thirty-nine percent (39/99) of the animals sampled on Jeløy, and 41% (34/82) of those from Askøy, Bergen and Os, carried S. Typhimurium 4,5,12:i:1,2. The PFGE profile of isolates from hedgehogs and human beings were identical within each of the two outbreak areas. A significantly higher carrier rate of S. Typhimurium occurred among hedgehogs sampled at feeding places, compared to those caught elsewhere. The salmonella-infected hedgehog populations most likely constituted the primary source of infection during both of the human disease outbreaks, and the Norwegian hedgehog is suggested as a reservoir host of S. Typhimurium 4,5,12:i:1,2.

Human articular chondrocytes express functional leptin receptors

The effects of leptin hormone are mediated by interactions with several physiological regulatory systems and the cytokine network, and by targeting cells directly. The leptin receptor is a member of the class I cytokine receptor family, and its signal transduction resembles that induced by many cytokines. We demonstrated that serially cultured human articular chondrocytes possess the leptin receptor (Ob-R), and that this receptor was present on chondrocytes in native human cartilage. In cultured chondrocytes we detected mRNA for the functional isoform of leptin receptor (Ob-Rb or Ob-R(L)), and it was revealed that ligand binding resulted in phosphorylation of signal transducers and activators of transcription, namely STAT1 and STAT5. Chondrocytes stimulated with leptin exhibited an increased proliferation and an enhanced synthesis of extracellular matrix (proteoglycans and collagen). These results indicate that leptin affects cartilage generation directly, which is a novel role for leptin in skeletal growth and development.

[Treatment of focal cartilage injuries in the knee]

Chondrocytes in adult human cartilage have little mitotic capacity even after injuries. Deep injuries penetrating the subchondral bone plate lead to the release of pluripotent mesenchymal stem cells which have the potential to differentiate into different types of connective tissue, including bone and cartilage. The release and stimulation of these stem cells can also be achieved by drilling or microfracture of the subchondral bone of cartilage lesions. When stimulated, periosteal cells may also differentiate into chondrocytes. However, non-chondrocyte determined cells seem to induce mainly fibrocartilage. In 1987 autologous chondrocyte implantation was introduced by a team in Gothenburg. This resulted in clinical improvement and the development of hyaline-like cartilage in patients who had undergone treatment. We first used the method in 1996 in a clinical trial. At a 6-month follow-up of our first 12 patients we found reduced symptoms and improved knee function. This method is promising, but further clinical trials are necessary.

[Accessory soleus muscle as a tumor in the ankle region]

We report the case of a 21-year ice hockey player with an accessory soleus muscle located medially in the ankle region. The swelling made it increasingly difficult for him to fit his skating boots and caused some pain during play. He was successfully treated by excising the muscle. Previously, the diagnosis was verified surgically in most reported cases. Like most recent authors, we believe that the diagnosis can be confirmed by CT-scan and/or MRI-scan. Surgical excision of the muscle should be reserved for symptomatic cases.

Differential regulation of messenger ribonucleic acids for specific subunits of cyclic adenosine 3',5'-monophosphate (cAMP)-dependent protein kinase by cAMP in rat Sertoli cells

In the present study we have examined the effects of FSH, forskolin, and (Bu)2cAMP on messenger RNA (mRNA) levels for all known subunits of cAMP-dependent protein kinase in rat Sertoli cells, using newly developed complementary DNA (cDNA) probes. mRNAs for the three regulatory subunits [RI alpha, RII51, (RII beta), and RII54 (RII alpha)] and the catalytic subunit C alpha were shown to be present in cultured rat Sertoli cells, whereas mRNAs for the subunits designated RI beta and C beta were below the level of detection. A high-levelled, concentration-dependent increase in a 3.2 kilobase mRNA for RII51 was observed when cultured immature Sertoli cells were incubated with increasing concentrations of (Bu)2cAMP (10(-6) to 5 X 10(-3) M) for 16 h. Densitometric scanning indicated a maximal stimulation by (Bu)2cAMP of 30- to 40-fold. Incubation with forskolin (100 microM) and FSH (200 ng/ml) gave rise to a smaller but significant increase in mRNA for RII51. When cultured Sertoli cells were incubated in the presence of 10(-4) M (Bu)2cAMP for varying time periods, there was a biphasic regulation of mRNA for RII51. (Bu)2cAMP caused an initial increase in mRNA for RII51 with maximal levels obtained after 10-16 h, after which a time-dependent decrease was observed. For the other three subunits present in Sertoli cells (RI alpha, RII54, and C alpha) a smaller but significant stimulation by (Bu)2cAMP and forskolin (2-4 fold) was seen. The functional implications of these changes in mRNA levels for the different subunits of cAMP-dependent protein kinase have not yet been revealed. However, our data clearly demonstrate differential regulation of the various subunits of cAMP-dependent protein kinase in Sertoli cells. Furthermore, these results document the presence of distinct adaptational changes taking place at the level of cAMP-dependent protein kinase in response to long term elevation of cAMP.

Failure of methapyrilene to induce tumors in hamsters or guinea pigs

In a small-scale experiment, 12 male and 12 female strain 2 guinea pigs were treated by gavage twice a week for 78 wk with a 200-mg/kg body weight dose of methapyrilene hydrochloride dissolved in water, a total dose of approximately 30 g/kg body weight. By the end of the treatment more than half of the animals were still alive: survivors were killed at 132 wk. A group of 20 male Syrian golden hamsters was treated twice a week by gavage with 15 mg methapyrilene hydrochloride for 58 wk, a total dose of approximately 15 g/kg body weight. Thirteen animals survived an acute convulsant effect, and the last 4 were killed at wk 61. There was no significant incidence of any tumor that could be attributed to the treatment in either guinea pigs or hamsters.

Fluorometric determination of DNA and RNA in Chlamydomonas using ethidium bromide

By using the fluorescence enhancement of ethidium bromide bound to nuclei acid, a very rapid, simple and sensitive assay of DNA in the green alga Chlamydomonas has been devised. Total fluorescence (DNA + RNA) was determined by complex formation with ethidium bromide in a cell lysate made by mixing cell samples with lauroyl sarcosinate, EDTA and NaOH and incubating the mixture for 5 min at room temperature followed by neutralization. For determination of DNA the RNA was digested by incubating the cell sample in te alkaline lysis solution for 45 min at 60 degrees C followed by neutralization, and complex formation with ethidium bromide. Quenching of the fluorescence due to cellular pigments was corrected for using an internal DNA standard.

Synchronized cultures of a cell wall-less mutant of Chylamydomonas reinhardii

Synchronization and synchronous growth of a cell wall-less mutant of Chlamydomonas reinhardii have been described. The following growth conditions were used: A modified Sueokas' "high salt minimal medium", 14:10 h light-dark cycle, growth temperature 30 degrees C, light intensity 12-18 Klux and dilution of the culture at the end of the dark to a constant density of 1.0 . 10(6) cells/ml. The time course of increase and distribution of cell volume, cytopla-smic and nuclear division, release of motile cells after the division period and accumulation of DNA, RNA and protein are reported. These mutant cells did not make any sporangium in which the dividing cells were kept as a unit inside a mother cell wall. However, they usually adhered during the period of division, thus making clumps containing 2, 4 and 8 cells. Several of these cell clumps dissolved releasing either single or couples of 2 and 4 cells. After the end of division the cells became fl

Variations in the carotenoid content of Chlamydomonas reinhardii throughout the cell cycle

Synchronous cultures of Chlamydomonas reinhardii have been examined for the total amounts of carotenoid and chlorophyll present throughout a 12 hrs light -- 4 hrs dark life cycle. Variations in the carotenoid distribution at different points within the cell cycle have been found. During the greater part of the light period all major carotenoids increased at a proportionally similar rate. However, the increases in lutein and violaxanthin preceded those in beta-carotene and neoxanthin by some 2 hrs and that in loroxanthin, and algal xanthophyll, by abour 3 hrs. A marked drop in total carotenoid accumulation, corresponding to similar temporary falling away in the accumulation of beta-carotene, lutein and violaxanthin occurred at 9 hrs. The correspondence of this with the established drop in RNA accumulation and the break-up of the nucleolus was pointed out. Considerable redistribution among the carotenoids occurred during the dark period, notably the amount of beta-carotene increased relative to the total xanthophylls. The full significance of these results can not be estimated in the absence of comparative data on related organisms.

The capacity for arylsulfatase synthesis in synchronous and synchronized cultures of Chlamydomonas reinhardti

The green algae Chlamydomonas reinhardti synthesizes arylsulfatase (arylsulfate sulfohydrolase EC 3.1.6.1) by derepression when the concentration of SO4-2-minus in the growth medium is less than about 5-10-minus 5 M. The following observations indicate that the arylsulfatase enzyme is stable while its mRNA was unstable: (1) The increase in enzyme activity stopped and remained constant after addition of cycloheximide to derepressed cells. (2) After readdition of SO4-2-minus the increase in enzyme activity continued at a lower rate whereafter it remained constant. (3) No decay of radioactivity was observed after readdition of SO4 2-minus in labelled enzyme protein isolated from pulse-labelled --S cells. The maximum rate of arylsulfatase synthesis. Measurements of this capacity in cells taken at different developmental stages from a selection synchronous and from a light-dark synchronized culture showed that: (1) Arylsulfatase was derepressible at all stages of the life cycle. (2) The same periodic capacity patterns were found, both with the synchronized and the synchronous cells. Furthermore, the rate of accummulation of RNA and protein changed in the same periodic manner during the life cycle as did the enzyme capacity.