Good healing potential of patellar chondral defects after all-arthroscopic autologous chondrocyte implantation with spheroids: a second-look arthroscopic assessment

Abstract

PurposeTo report second‐look arthroscopic assessment after all‐arthroscopic autologous chondrocyte implantation (ACI) for articular cartilage defects at the patella. MethodsA second‐look arthroscopy after all‐arthroscopic ACI using chondrospheres® (ACT3D) was performed in 30 patients with 30 full‐thickness retropatellar cartilage defects. The mean time from ACI to second‐look arthroscopy was 14.9 ± 16.3 (6–71) months. The quality of cartilage regeneration was evaluated by the International Cartilage‐Repair Score (ICRS)—Cartilage Repair Assessment (CRA). ResultsEleven lesions (36.7%) were classified as CRA grade I (normal) and 19 lesions (63.3%) as grade II (nearly normal). Concerning the degree of defect repair, 25 lesions (83.3%) were repaired up to the height of the surrounding articular retropatellar cartilage. Five lesions (16.7%) showed 75% repair of defect depth. The border zone was completely integrated into the surrounding articular cartilage shoulder in 28 lesions (93.3%) and demarcated within 1 mm in 2 lesions (6.7%). Macroscopically and by probing, 12 lesions (40%) had intact smooth surface, 17 lesions (56.7%) had fibrillated surface and 1 lesion (3.3%) had small, scattered fissures. A negative correlation was found between the overall repair assessment score and the defect size (r2 = − 0.430, p = 0.046) and between integration into border zone and defect size (r2 = − 0.340, p = 0.045). A positive correlation was found between macroscopic appearance and age (r2 = + 0.384, p = 0.036). ConclusionsAll‐arthroscopic ACI using chondrospheres® (ACT3D) for full‐thickness retropatellar articular cartilage defects proved to be reproducible and reliable. The advantage of the procedure is that it is minimal invasive. Arthroscopic second‐look demonstrated a high grade of normal or nearly normal cartilage regeneration. Although statistically significant differences were not observed, larger defect size and younger age may compromise the result of overall repair. Level of evidenceIII.

Excellent Clinical and Radiological Outcomes after both Open Flake Refixation and Autologous Chondrocyte Implantation following Acute Patella Dislocation and Concomitant Flake Fractures

“…Interestingly, the present study showed that patients treated with ACI for flake fractures after patella dislocation show excellent results. The clinical outcome and return-to-sport rates were better than most of the results after patellofemoral ACI published so far [2,10,21,29,31]. In a current systematic review, Hinckel et al showed that patellofemoral cartilage restoration leads to good clinical results, but with a higher complication rate in comparison to the present study [10].…”

Role of Matrix-Associated Autologous Chondrocyte Implantation with Spheroids in the Treatment of Large Chondral Defects in the Knee: A Systematic Review

“…The literature search yielded 34 publications in PubMed and 70 in Web of Science. After removing 29 duplicates and screening the titles and abstracts, the full texts of 21 publications were screened, after which 18 [7,[10][11][12][13][14][15][17][18][19][20][21][22][23][24][25][26][27] were included and 3 [28][29][30] were excluded due to the use of xenogeneic materials [28] or antibiotics [29] in the cell culture, or the spheroids were formed by pelleting cells with centrifugation [30]. Two additional articles [16,31] were identified from citations (Figure 2).…”

“…It has to be noted here that the adolescent patients were treated with chondrosphere in Germany under the German regulations. ACI with spheroids provided good patient-reported outcome scores [15][16][17][18][19], MRI [15,16,18,19], macroscopic [17,22], and histological [20] evaluations in patients with a routine treatment (Table 3).…”

“…As the spheroids are self-adhesive to the subchondral bone by extracellular matrix interactions, there is no need for additional cell carriers, covers, membranes, or sutures [15]. Therefore, the spheroids can be implanted with minimal invasiveness with an arthroscopy [22]. In addition, xenogenous scaffold material can interact with human cells and affect their performance [41].…”

Therapeutic strategies of three-dimensional stem cell spheroids and organoids for tissue repair and regeneration

“…These chondrocyte spheroids were prepared by culturing 1 × 10 5 and/or 2 × 10 5 cells in agarose hydrogel-coated 96 well plates [ 182 ]. Patients Implanted with less than 70 spheroids showed substantial improvement in various clinical outcomes [ 180 , [183] , [184] , [185] ]. Based on these clinical results, it is expected that the treatment efficiency of limited cartilage can be improved if stem cell-based spheroids are used as cell therapy by replacing chondrocytes in this treatment technology with stem cells.…”