CARTILAGE

This study is a literature review from 2010 to 2014 concerning the quality of evidence in clinical trials about microfracture in attempt to repair articular cartilage. We have decided to focus on microfracturing, since this seems to be the best documented technique. Interest in evaluation of publication quality has risen in orthopaedic sports medicine recently. Therefore, we think it is necessary to evaluate recent clinical trials being rated for their evidence-based medicine (EBM) quality. We also compared the mean impact factor of the journals publishing the different studies as an indicator of the study’s citation and evaluated for a change over the studied time frame.

To measure the EBM level, we applied the modified Coleman Methodology Score (CMS) introduced by Jakobsen. The impact factor, which is a measurement of the yearly average number of citations of articles recently published in that journal, was evaluated according to self-reported values on the corresponding journal’s website.

We found that the mean CMS has not changed between 2010 and 2014. The mean impact factor has also not changed between 2010 and 2014. The CMS variance was high, pointing to different qualities in the evaluated studies. There is no evidence that microfracturing is superior compared to other cartilage repair procedures.

Microfracture cannot be seen as an evidence based procedure. Further research needs to be done and a standardization of the operating method is desirable. There need to be more substantial studies on microfracturing alone without additional therapies.

In the management of knee osteoarthritis (OA), patient-reported-outcomes (PROs) are being developed for relevant assessment of pain. The patient acceptable symptom state (PASS) is a relevant cutoff, which allows classifying patients as being in “an acceptable state” or not. Viscosupplementation is a therapeutic modality widely used in patients with knee OA that many patients are satisfied with despite meta-analyses give conflicting results.

To compare, 6 months after knee viscosupplementation, the percentage of patients who reached the PASS threshold (PASS +) with that obtained from other PROs.

Data of 53 consecutive patients treated with viscosupplementation (HANOX-M-XL) and followed using a standardized procedure, were analyzed at baseline and month 6. The PROs were Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function, patient’s global assessment of pain (PGAP), patient’s self-assessment of satisfaction, PASS for WOMAC pain and PGAP.

At baseline, WOMAC pain and PGAP (range 0-10) were 4.6 (1.1) and 6.0 (1.1). At month 6, they were 1.9 (1.2) and 3.1 (5) (P < 0.0001). At 6 months, 83% of patients were “PASS + pain,” 100% “PASS + function,” 79% “PASS + PGAP,” 79% were satisfied, and 73.6% experienced a ≥50% decrease in WOMAC pain. Among “PASS + pain” and “PASS + PGAP” subjects, 90% and 83.3% were satisfied with the treatment, respectively.

In daily practice, clinical response to viscosupplementation slightly varies according to PROs. “PASS + PGAP” was the most related to patient satisfaction.

Osteoarthritis (OA) is induced by accumulated mechanical stress to joints; however, little has been reported regarding the cause among detailed mechanical stress on cartilage degeneration. This study investigated the influence of the control of abnormal joint movement induced by anterior cruciate ligament (ACL) injury in the articular cartilage.

The animals were divided into 3 experimental groups: CAJM group (n = 22: controlling abnormal joint movement), ACL-T group (n = 22: ACL transection or knee anterior instability increased), and INTACT group (n = 12: no surgery). After 2 and 4 weeks, the knees were harvested for digital microscopic observation, soft X-ray analysis, histological analysis, and synovial membrane molecular evaluation.

The 4-week OARSI scores showed that cartilage degeneration was significantly inhibited in the CAJM group as compared with the ACL-T group (P < 0.001). At 4 weeks, the osteophyte formation had also significantly increased in the ACL-T group (P < 0.001). These results reflected the microscopic scoring and soft X-ray analysis findings at 4 weeks. Real-time synovial membrane polymerase chain reaction analysis for evaluation of the osteophyte formation–associated factors showed that the mRNA expression of BMP-2 and VEGF in the ACL-T group had significantly increased after 2 weeks.

Typically, abnormal mechanical stress induces osteophyte formation; however, our results demonstrated that CAJM group inhibited osteophyte formation. Therefore, controlling abnormal joint movement may be a beneficial precautionary measure for OA progression in the future.

The aim of this study was to evaluate the results of autologous bone marrow cell stimulation and allogenic chondrocyte implantation using 3-dimensional gel-type fibrin matrix in an animal model.

Eighteen rabbits were divided into 2 treatment groups. One group was treated with a microfracture and covering of it with gel-type fibrin (AutoBMS; n = 9), and the other group was treated with allogenic chondrocytes mixed gel-type fibrin at the cartilage defect (AlloCI; n = 9). The control group was untreated cartilage defect at the other side knee of each object. Twelve weeks after treatment, the cartilage was evaluated using the International Cartilage Repair Society (ICRS) scoring system, immunohistochemical staining, and modified O’Driscoll grading system.

The ICRS scores were similar in the AutoBMS (9.44 ± 2.44) and the AlloCI (9.33 ± 1.67) groups (P < 0.05). Immunohistochemical staining confirmed higher expression of cartilaginous collagen for both groups. The average difference (AutoBMS, 31.89 ± 6.54; AlloCI, 32.89 ± 5.25) in the modified O’Driscoll scores appeared to be nonsignificant (P > 0.05); however, both treatment groups showed significantly higher scores with respect to their control group (18.45 ± 1.65; 18.97 ± 1.58) (P < 0.05).

This experimental study suggests autologous bone marrow cells stimulation and implantation of allogenic chondrocytes are both useful methodologies for regenerating hyaline-like cartilage in full-thickness cartilage defects in animal model.

This study aimed to compare microfracture and application of adipose-derived stem cells (ADSCs) by local adherent technique enhanced by platelet-rich plasma (PRP) to provide a new approach for the repair of cartilage defect.

Full-thickness cylindrical defects were created in the medial femoral condyle in 9 New Zealand White rabbits (5 months old, 4.65 ± 0.20 kg). Two groups of rabbits (n = 3) were either treated with ADSCs (Group 1) or the microfracture technique (Group 2) following intraarticular injection of PRP 3 times in weekly intervals. Rabbits in control group (n = 3) remained untreated. The outcome was assessed macroscopically, histologically, and immunohistochemically.

At the end of week 12, Group 1 showed better defect filling compared with Group 2. Specimens treated with the combination of ADSCs and PRP exhibited significant differences from the other groups in all criteria of International Cartilage Repair Society macroscopic scoring system.

Intraarticular injection of autologous PRP in combination with transplantation of autologous ADSCs by local adherent technique enhances the quality of cartilage defect repair with better results in comparison with microfracture surgery in a rabbit model.

To test different fixation methods of a 3-dimensionally woven poly(ϵ-caprolactone) (PCL) scaffold within chondral defects of a weightbearing large animal model.

Full thickness chondral defects were made in the femoral condyles of 15 adult male Yucatan mini-pigs. Two surgical approaches were compared including total arthrotomy (traditional) and a retinaculum-sparing, minimally invasive surgery (MIS) approach. Following microfracture (MFX), scaffolds were placed without fixation or were fixed with fibrin glue, suture, or subchondral anchor. Experimental endpoints were between 1 and 6 weeks. Micro–computed tomography and histology were used to assess samples.

The MIS approach was superior as the traditional approach caused medial condyle cartilage wear. One of 13 (7.7%) of scaffolds without fixation, 4 of 11 (36.3%) fibrin scaffolds, 1 of 4 (25%) of sutured scaffolds, and 9 of 9 (100%) of anchor-fixed scaffolds remained in place. Histology demonstrated tissue filling with some overgrowth of PCL scaffolds.

Of the methods tested, the MIS approach coupled with subchondral anchor fixation provided the best scaffold retention in a mini-pig chondral defect model. This finding has implications for fixation strategies in future animal studies and potential future human use.

To establish whether a novel biomaterial scaffold with tunable degradation profile will aid in cartilage repair of chondral defects versus microfracture alone in vitro and in a rat model in vivo.

In vitro—Short- and long-term degradation scaffolds were seeded with culture expanded articular chondrocytes or bone marrow mesenchymal stem cells. Cell growth and differentiation were evaluated with cell morphological studies and gene expression studies. In vivo—A microfracture rat model was used in this study to evaluate the repair of cartilage and subchondral bone with the contralateral knee serving as the empty control. The treatment groups include (1) empty osteochondral defect, (2) polycaprolactone copolymer–based polyester polyurethane–urea (PSPU-U) caffold short-term degradative profile, and (3) PSPU-U scaffold long-term degradative profile. After placement of the scaffold, the rats were then allowed unrestricted activity as tolerated, and histological analyses were performed at 4, 8, and 16 weeks. The cartilage defect was measured and compared with the contralateral control side.

In vitro—Long-term scaffolds showed statistically significant higher levels of aggrecan and type II collagen expression compared with short-term scaffolds. In vivo—Within 16 weeks postimplantation, there was new subchondral bone formation in both scaffolds. Short-term scaffolds had a statistically significant increase in defect filling and better qualitative histologic fill compared to control.

The PSPU short-term degradation scaffold may aid in cartilage repair by ultimately incorporating the scaffold into the microfracture procedure.