Enhanced microfracture using acellular scaffolds improves results after treatment of symptomatic focal grade III/IV knee cartilage lesions but current clinical evidence does not allow unequivocal recommendation

Comparison of 3 Cell-Free Matrix Scaffolds Used to Treat Osteochondral Lesions in a Rabbit Model

BACKGROUND

Various cell-free scaffolds are already in use for the treatment of osteochondral defects (OCDs); however, a gold standard material has not yet been defined.

PURPOSE

This study compared the macroscopic, histological, and scanning electron microscopy (SEM) characteristics of Chondro-Gide (CG), MaioRegen (MA), and poly-d,l-lactide-co-caprolactone (PLCL) cell-free scaffolds enhanced with small-diameter microfractures (SDMs) for OCDs in a rabbit model.

STUDY DESIGN

Controlled laboratory study.

METHODS

In total, 54 knees from 27 rabbits were used in this study. Three rabbits were sacrificed at the beginning of the study to form an intact cartilage control group (group IC). An OCD model was created at the center of the trochlea, and SDMs were generated in 24 rabbits. Rabbits with OCDs were divided into 4 groups (n = 12 knees per group) according to the cell-free scaffold applied: CG (group CG), MA (group MA), PLCL (group PLCL), and a control group (group SDM). Half of the rabbits were sacrificed at 1 month after treatment, while the other half were sacrificed at 3 months after treatment. Healed cartilage was evaluated macroscopically (using International Cartilage Regeneration & Joint Preservation Society [ICRS] classification criteria) and histopathologically (using modified O'Driscoll scores and collagen staining). Additionally, cell-free scaffold morphologies were compared using SEM analysis.

RESULTS

ICRS and modified O'Driscoll classification and staining with collagen type 1 and type 2 demonstrated significant differences among groups at both 1 and 3 months after treatment (P < .05). The histological characteristics of the group IC samples were superior to those of all other groups, except group PLCL, at 3 months after treatment (P < .05). In addition, the histological properties of group PLCL samples were superior to those of group SDM samples at both 1 and 3 months after treatment in terms of the modified O'Driscoll scores and type 1 collagen staining (P < .05). Concerning type 2 collagen staining intensity, the groups were ranked from highest to lowest at 3 months after treatment as follows: group PLCL (30.3 ± 2.6) > group MA (26.6 ± 1.2) > group CG (23.3 ± 2.3) > group SDM (18.9 ± 0.9).

CONCLUSION

OCDs treated with enhanced SDM using cell-free PLCL scaffolds had superior histopathological and microenvironmental properties, more hyaline cartilage, and more type 2 collagen compared with those treated using CG or MA scaffolds.

CLINICAL RELEVANCE

OCDs treated with PLCL cell-free scaffolds may have superior histopathological properties and contain more type 2 collagen than do OCDs treated with CG or MA cell-free scaffolds.

Comparison of All Arthroscopic Implantation of Chitosan-Based Liquid Scaffold and Hyaluronan-Based Soft Scaffold in the Treatment of Condylar Osteochondral Lesions in the Knee

Cell-free scaffolds used in cartilage regeneration are produced from different materials. The aim of this study is to compare the clinical and radiological results of two different scaffolds with hyaluronan- or chitosan-based structure used in the treatment of symptomatic condylar osteochondral lesions. The study comprises 69 patients who were operated for osteochondral lesion repair with hyaluronan- (n = 37) or chitosan-based (n = 32) scaffold. The International Knee Documentation Committee (IKDC), Lysholm Knee Scoring Scale and Visual Analog Scale (VAS) scores were collected for both groups at the preoperative and postoperative 3rd, 12th, and 24th months. Magnetic resonance imaging was performed between the 12th and 15th months postoperatively and this with magnetic resonance observation of cartilage repair tissue (MOCART) scoring were compared. Within group assessments demonstrate significant improvement in IKDC, Lysholm, and VAS scores at postoperative 3rd and 12th months. However, in both groups, IKDC, Lysholm and, VAS scores at the postoperative 24th month indicate no significant further improvement, compared with the 12th month results. There was no significant difference between the groups in terms of IKDC, Lysholm, VAS, and MOCART scores at any time period. This study shows that both scaffolds are useful in cartilage regeneration but have no clinical or radiological superiority to each other. Surgeons should select the method with which they feel comfortable. This is a level III, retrospective comparative study.

Clinical Outcomes of an All-Arthroscopic Technique for Single-Stage Autologous Matrix-Induced Chondrogenesis in the Treatment of Articular Cartilage Lesions of the Knee

Purpose

The purpose of this study was to determine the clinical efficacy of an all-arthroscopic approach to autologous matrix-induced chondrogenesis (AMIC) for patients with articular cartilage lesions of the knee joint. We hypothesize that an all-arthroscopic, single-stage AMIC using a hyaluron-based cell-free scaffold improves the postoperative clinical scores for patients with isolated articular cartilage lesions of the knee in the early follow-up period.

Methods

All patients with focal osteochondral lesions of the knee treated with AMIC at our institution from November 2013 to January 2018 were included for analysis. Demographic information, baseline clinical characteristics, perioperative imaging, and follow-up International Knee Documentation Committee (IKDC) scores at 6 and 24 months postoperatively were collected. One-way analysis of variance (ANOVA) with a Bonferroni correction was used to assess for improvement before and after surgery, with statistical significance defined as p < .05.

Results

A total of 22 patients met the inclusion criteria and were analyzed for this study. Articular cartilage lesions were most commonly found at the center of the medial and lateral femoral condyles. Statistically significant improvements in IKDC scores were seen at the 6- and 24-month follow-up periods (p < .05).

Conclusion

An all-arthroscopic technique for single-stage autologous matrix-induced chondrogenesis demonstrates significant early clinical improvement for the treatment of articular cartilage lesions of the knee.

Level of Evidence

4

A Technique Using a Low-Cost, Accessible Cannula to Aid Scaffold Passage in Dry Arthroscopic Cartilage Repair in the Knee

Although autologous matrix-induced chondrogenesis has grown increasingly popular, it can be technically challenging to place the scaffold within the knee efficiently without extending the arthroscopic incisions. To facilitate arthroscopic placement of the matrix into the knee, we developed a technique that involves fashioning a cannula from a standard 5-mL syringe. This technique enables surgeons to conveniently and efficiently place the matrix through the standard arthroscopic ports at minimal cost.