ePoster #1302 - 2013 ISAKOS Biennial Congress

Intralesional Ostephyte Regrowth Following Autologous Chondrocyte Implantation

Marco Kawamura Demange, MD., Ph.D., Sao Paulo, SP, BRAZIL
Arvind Von Keudell, M.D., Boston, MA, USA
Andreas H. Gomoll, MD, Boston, MA, USA
Tim Bryant, B.Sc., Boston, MA, USA
Sonal Sodha, M.D., Boston, USA
Tom Minas, MD, Chestnut Hill, MA, USA
Harvard Medical School, Boston, MA, USA

The FDA has not cleared the following pharmaceuticals and/or medical device for the use described in this presentation. The following pharmaceuticals and/or medical device are being discussed for an off-label use: Geistlich, Geistlich Bio-Gide

Summary: Removed intralesional osteophytes may regrowth after autologous chondrocyte implantation in a significant number of cases.

Abstract:
Background:
Marrow stimulation techniques such as drilling, abrasion arthroplasty, or microfracture are many times considered first-line treatment options for symptomatic cartilage defects. Autologous chondrocyte implantation (ACI) may be performed as a second line treatment for failed bone marrow stimulation treatment of full-thickness cartilage defects, as well as a first line treatment in larger lesions. Recent studies, however, have demonstrated subchondral bone changes in up to one third of patients treated with microfracture, such as thickening of the subchondral bone, osseous overgrowth and formation of subchondral cysts. During the autologous chondrocyte implantation surgery, after cartilage lesion debridement, the subchondral bone aspect is evaluated and Intralesional osteophytes and sclerotic bones are removed.

Question:
Does removed intralesional osteophyte regrow after autologous chondrocyte implantation procedure?

Methods:
We prospectively followed 165 patients with intralesional osteophytes who underwent a autologous chondrocyte implantation surgery from June 1995 to December 2009. Intralesional ostephyte were removed with a high-speed burr during surgery. A periosteal patch was used until May 2007 and a type 2 porcine collagen membrane was used after that. All patients had intraoperative surgical pictures to document the intralesional ostephyete. We obtained MRI with minimum of 1-year follow-up from 99 patients. We analyzed all the MRI looking for osteophyte regrowth and cystic changes to the subchondral bone.

Results:
Osteophyte regrowth was observed in 21% of the patients and cystic changes were observed in 17% of the patients.

Discussion:
Alterations to subchondral bone as the presence of intralesional osteophytes secondary to previous bone marrow stimulation procedures may irreversibly affect the subchondral bone unit. Surgeons should consider those possible complications in order to select the best first line surgical procedure in the treatment of cartilage defects. Better understanding of the subchondral bone unit as well as the influence of recurrent intralesional osteophytes on long term clinical outcomes are necessary to improve treatment guidelines of cartilage defects in the presence of subchondral bone disruption.

Conclusion:
Removed intralesional osteophytes may regrowth after autologous chondrocyte implantation in a significant number of cases.