Treatment of full-thickness chondral defects with hyalograft C in the knee: a prospective clinical case series with 2 to 7 years' follow-up.
BACKGROUND
Tissue engineering has become available for cartilage repair in clinical practice.


OBJECTIVE
The treatment of full-thickness chondral defects in the knee with a hyaluronan-based scaffold seeded with autologous chondrocytes provides stable improvement of clinical outcome up to 7 years.


METHODS
Case series; Level of evidence, 4.


METHODS
Fifty-three patients with deep osteochondral defects in the knee were treated with Hyalograft C. The mean age at implantation was 32 +/- 12 years, the mean defect size was 4.4 +/- 1.9 cm(2), and the mean body mass index was 24.5 +/- 3.8 kg/m(2). Implantations were performed with miniarthrotomy or arthroscopy. The primary indications for implantation with Hyalograft C included young patients with a stable joint, normal knee alignment, and isolated chondral defects with otherwise healthy adjacent cartilage. The secondary indications were patients who did not meet the primary indication criteria or were salvage procedures. Forty-two patients with primary indications and 11 patients with secondary indications were evaluated. Outcome was evaluated with the International Cartilage Repair Society and International Knee Documentation Committee scales, the Lysholm score, the modified Cincinnati score, and with Kaplan-Meier survival analysis. Statistical analysis consisted of bivariate correlation analysis and unpaired, 2-tailed t tests.


RESULTS
A highly significant increase (P <.001) in all knee scores was found in patients treated for the primary indications. Nine of 11 secondary indication cases underwent total knee arthroplasty due to persisting pain between 2 and 5 years after implantation. Graft failure occurred in 3 of 42 patients with primary indication between 6 months and 5 years after implantation. Kaplan-Meier survival demonstrated significantly different chances for survival between primary and secondary outcome and between simple, complex, and salvage cases, respectively (P <.001).


CONCLUSIONS
Hyalograft C autograft provides clinical improvement in healthy young patients with single cartilage defects. Less complicated surgery and lower morbidity are considered advantages of the technique. The results of treatment with Hyalograft C as a salvage procedure or in patients with osteoarthritis are poor.
Nehrer
Stefan
S
Centre of Regenerative Medicine, Danube University, Krems, Austria.
Dorotka
Ronald
R
Domayer
Stephan
S
Stelzeneder
David
D
Kotz
Rainer
R
D000328:Adult; D001317:Austria; D002358:Cartilage, Articular / Q000293:injuries* / Q000601:surgery; D019902:Chondrocytes / Q000637:transplantation*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006820:Hyaluronic Acid / Q000627:therapeutic use*; D007718:Knee Injuries / Q000534:rehabilitation / Q000601:surgery*; D007719:Knee Joint / Q000601:surgery; D008297:Male; D019637:Orthopedic Procedures / Q000379:methods; D017063:Outcome Assessment, Health Care; D011446:Prospective Studies; D054457:Tissue Scaffolds; D014182:Transplantation, Autologous / Q000379:methods*; D055815:Young Adult
D006820:Hyaluronic Acid