title: Can osteochondral grafting be augmented with microfracture in an extended-size lesion of articular cartilage?
abstract: BACKGROUND
  Both microfracture and osteochondral autografting procedures have been useful in treating osteochondral lesions.
  
  
  OBJECTIVE
  Combining microfracture and osteochondral autografting procedures can extend the size of lesions that can be treated with either technique.
  
  
  METHODS
  Descriptive laboratory study.
  
  
  METHODS
  Eight adult goats underwent osteochondral autograft transfer of a 4.5-mm femoral trochlea plug into an 8-mm full-thickness chondral defect. Microfracture was performed in the gap region surrounding the autograft. The animals were allowed normal activity until the end of the experiment at 6 months. At harvest, the knees were assessed grossly, and then evaluation was performed by histology, histomorphometry, biochemistry, and biomechanics.
  
  
  RESULTS
  The osteochondral plugs healed well, with integration of the bone and preservation of the chondral cap. The chondral gap between the host site articular cartilage and the transferred plug had decreased from 3 mm at implant to less than 0.1 mm. Histologic analysis demonstrated regions of variable cartilage repair, with integration of the cartilage layer at some sites but incomplete healing at others. Histomorphometry demonstrated filling of the chondral gap to 75% to 85% of the normal volume. Biochemical analysis revealed greater than 90% type II collagen at most sites, with some areas containing 80% type II collagen. Biomechanical indentation testing indicated that the repaired area had variable thickness and stiffness, with a trend of increased stiffness in the bulk graft and decreased softness at the proximal microfracture interface site.
  
  
  CONCLUSIONS
  The performance of a combined microfracture and osteochondral autograft transfer procedure to resurface a large chondral defect appears promising.
  
  
  CONCLUSIONS
  This combined technique shows promise for treatment of large chondral defects with a single operative procedure with autogenous tissue that is safe and potentially would have a shorter period of rehabilitation, similar to that of osteochondral transfers and microfracture, in a cost-effective setting.
authors.affiliation: Department of Orthopaedic Surgery, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093-0863, USA.
authors.forename: John G
authors.initials: JG
authors.lastname: Lane
authors.forename: Robert M
authors.initials: RM
authors.lastname: Healey
authors.forename: Albert C
authors.initials: AC
authors.lastname: Chen
authors.forename: Robert L
authors.initials: RL
authors.lastname: Sah
authors.forename: David
authors.initials: D
authors.lastname: Amiel
mesh_terms: D000818:Animals; D054544:Arthroplasty, Subchondral / Q000379:methods*; D001696:Biomechanical Phenomena; D016025:Bone Transplantation / Q000379:methods*; D002358:Cartilage, Articular / Q000166:cytology / Q000293:injuries* / Q000601:surgery*; D019902:Chondrocytes / Q000166:cytology; D024043:Collagen Type II / Q000032:analysis; D005269:Femur / Q000601:surgery; D006041:Goats; D051457:Hyaline Cartilage / Q000166:cytology / Q000637:transplantation*; D007718:Knee Injuries / Q000601:surgery; D007719:Knee Joint / Q000601:surgery
chemical_list: D024043:Collagen Type II
references.citation: J Bone Joint Surg Am. 2009 Apr;91(4):805-11
references.pmid: 19339564
references.citation: Am J Sports Med. 2009 Jan;37(1):42-55
references.pmid: 18927254
references.citation: Instr Course Lect. 2007;56:457-68
references.pmid: 17472328
references.citation: Clin Orthop Relat Res. 2001 Oct;(391 Suppl):S349-61
references.pmid: 11603718
references.citation: Knee Surg Sports Traumatol Arthrosc. 2006 Sep;14(9):834-42
references.pmid: 16552548
references.citation: Arthroscopy. 2003 May-Jun;19(5):477-84
references.pmid: 12724676
references.citation: Arthroscopy. 1986;2(1):54-69
references.pmid: 3954840
references.citation: J Knee Surg. 2002 Summer;15(3):191-5
references.pmid: 12152982
references.citation: Knee Surg Sports Traumatol Arthrosc. 2005 Apr;13(3):213-21
references.pmid: 15146311
references.citation: Arthroscopy. 2005 Sep;21(9):1066-75
references.pmid: 16171631
references.citation: Clin Sports Med. 1999 Jan;18(1):67-75
references.pmid: 10028117
references.citation: Clin Orthop Relat Res. 2005 Jun;(435):79-87
references.pmid: 15930924
references.citation: J Bone Joint Surg Am. 2003;85-A Suppl 2:17-24
references.pmid: 12721341
references.citation: J Bone Joint Surg Am. 2005 Sep;87(9):1911-20
references.pmid: 16140804
references.citation: MMWR Morb Mortal Wkly Rep. 2002 Mar 15;51(10):207-10
references.pmid: 11922189
references.citation: J Bone Joint Surg Am. 2003;85-A Suppl 2:25-32
references.pmid: 12721342
references.citation: J Bone Joint Surg Am. 2007 Apr;89(4):718-26
references.pmid: 17403792
references.citation: Orthopedics. 1998 Jul;21(7):761-7; discussion 767-8
references.pmid: 9672913
references.citation: Osteoarthritis Cartilage. 2004 Oct;12(10):826-33
references.pmid: 15450533
references.citation: Arthroscopy. 2004 Sep;20(7):681-90
references.pmid: 15346108
references.citation: Am J Sports Med. 2004 Sep;32(6):1440-50
references.pmid: 15310569
references.citation: Clin Orthop Relat Res. 2000 May;(374):212-34
references.pmid: 10818982
references.citation: Arthroscopy. 1988;4(2):72-80
references.pmid: 3395420
references.citation: Orthopedics. 2003 Sep;26(9):945-7
references.pmid: 14503759
references.citation: Osteoarthritis Cartilage. 1997 Sep;5(5):343-55
references.pmid: 9497941
references.citation: Am J Sports Med. 2002 Jan-Feb;30(1):2-12
references.pmid: 11798989
references.citation: Am J Sports Med. 2005 Oct;33(10):1479-84
references.pmid: 16009984
references.citation: Am J Sports Med. 2006 Sep;34(9):1413-8
references.pmid: 16735588
references.citation: Clin Orthop Relat Res. 1984 Jan-Feb;(182):200-5
references.pmid: 6692614
references.citation: Injury. 2008 Apr;39 Suppl 1:S32-9
references.pmid: 18313470
references.citation: J Knee Surg. 2002 Summer;15(3):170-6
references.pmid: 12152979
references.citation: Arthroscopy. 2006 Nov;22(11):1180-6
references.pmid: 17084294
references.citation: J Bone Joint Surg Am. 2006 Sep;88 Suppl 1 Pt 2:294-304
references.pmid: 16951101
references.citation: Connect Tissue Res. 1988;18(1):27-39
references.pmid: 3180813
references.citation: Sports Med Arthrosc Rev. 2008 Dec;16(4):196-201
references.pmid: 19011550