Novel scaffold-based BST-CarGel treatment results in superior cartilage repair compared with microfracture in a randomized controlled trial.
BACKGROUND
Microfracture, the standard of care, is recognized to be an incomplete solution for cartilage damage. BST-CarGel, a chitosan-based medical device, is mixed with autologous whole blood and is applied to a microfractured cartilage lesion in which it physically stabilizes the clot and guides and enhances marrow-derived repair. An international, multicenter, randomized controlled trial was conducted to evaluate BST-CarGel treatment compared with microfracture alone in the repair of cartilage lesions in the knee.


METHODS
Eighty patients between the ages of eighteen and fifty-five years with a single, symptomatic focal lesion on the femoral condyles were randomized to BST-CarGel and microfracture treatment (n = 41) or microfracture treatment alone (n = 39). The primary end points of repair tissue quantity and quality at twelve months were assessed by quantitative three-dimensional magnetic resonance imaging measuring the degree of lesion filling and T2 relaxation time with use of standardized one and twelve-month posttreatment scans. The secondary end point at twelve months was clinical benefit determined with the Western Ontario and McMaster Universities Osteoarthritis Index. The tertiary end point was quality of life determined by the Short Form-36. Safety was assessed through the recording of adverse events.


RESULTS
Patient baseline characteristics were similar in the two groups, although baseline lesion areas were slightly larger on quantitative magnetic resonance imaging for the BST-CarGel group compared with the microfracture group. Blinded quantitative magnetic resonance imaging analysis demonstrated that, at twelve months, when compared with microfracture treatment alone, BST-CarGel treatment met both primary end points by achieving statistical superiority for greater lesion filling (p = 0.011) and more hyaline cartilage-like T2 values (p = 0.033). The lesion filling values were 92.8% ± 2.0% for the BST-CarGel treatment group and 85.2% ± 2.1% for the microfracture treatment group, and the mean T2 values were 70.5 ± 4.5 ms for the BST-CarGel treatment group and 85.0 ± 4.9 ms for the microfracture treatment group. Western Ontario and McMaster Universities Osteoarthritis Index subscales for pain, stiffness, and function yielded equivalent improvement for both groups at twelve months, which were significant (p < 0.0001) from baseline. Treatment safety profiles were considered comparable.


CONCLUSIONS
At twelve months, BST-CarGel treatment resulted in greater lesion filling and superior repair tissue quality compared with microfracture treatment alone. Clinical benefit was equivalent between groups at twelve months, and safety was similar.
Department of Surgery, Dalhousie University, 5595 Fenwick Street, Suite 311, Halifax, NS B3H 4M2, Canada. E-mail address: wstanish@ns.sympatico.ca.
William D
WD
Stanish
Robert
R
McCormack
Francisco
F
Forriol
Nicholas
N
Mohtadi
Stéphane
S
Pelet
Jacques
J
Desnoyers
Alberto
A
Restrepo
Matthew S
MS
Shive
D000293:Adolescent; D000328:Adult; D054544:Arthroplasty, Subchondral; D001182:Arthroscopy / Q000009:adverse effects / Q000379:methods*; D002358:Cartilage, Articular / Q000601:surgery*; D048271:Chitosan / Q000627:therapeutic use*; D005260:Female; D005269:Femur / Q000601:surgery*; D006801:Humans; D051457:Hyaline Cartilage / Q000601:surgery* / Q000637:transplantation; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D011474:Prosthesis Design / Q000379:methods*; D011788:Quality of Life; D016896:Treatment Outcome; D014945:Wound Healing; D055815:Young Adult
D048271:Chitosan