The Incidence and Clinical Relevance of Graft Hypertrophy After Matrix-Based Autologous Chondrocyte Implantation

Background: Graft hypertrophy is the most common complication of periosteal autologous chondrocyte implantation (p-ACI). Purpose: The aim of this prospective study was to analyze the development, the incidence rate, and the persistence of graft hypertrophy after matrix-based autologous chondrocyte implantation (mb-ACI) in the knee joint within a 2-year postoperative course. Study Design: Case series; Level of evidence, 4. Methods: Between 2004 and 2007, a total of 41 patients with 44 isolated cartilage defects of the knee were treated with the mb-ACI technique. The mean age of the patients was 35.8 years (standard deviation [SD], 11.3 years), and the mean body mass index was 25.9 (SD, 4.2; range, 19-35.3). The cartilage defects were arthroscopically classified as Outerbridge grades III and IV. The mean area of the cartilage defect measured 6.14 cm2 (SD, 2.3 cm2). Postoperative clinical and magnetic resonance imaging (MRI) examinations were conducted at 3, 6, 12, and 24 months to analyze the incidence and course of the graft. Results: Graft hypertrophy developed in 25% of the patients treated with mb-ACI within a postoperative course of 1 year; 16% of the patients developed hypertrophy grade 2, and 9% developed hypertrophy grade 1. Graft hypertrophy occurred primarily in the first 12 months and regressed in most cases within 2 years. The International Knee Documentation Committee (IKDC) and visual analog scale (VAS) scores improved during the postoperative follow-up time of 2 years. There was no difference between the clinical results regarding the IKDC and VAS pain scores and the presence of graft hypertrophy. Conclusion: The mb-ACI technique does not lead to graft hypertrophy requiring treatment as opposed to classic p-ACI. The frequency of occurrence of graft hypertrophy after p-ACI and mb-ACI is comparable. Graft hypertrophy can be considered as a temporary excessive growth of regenerative cartilage tissue rather than a true graft hypertrophy. It is therefore usually not a persistent or systematic complication in the treatment of circumscribed cartilage defects with mb-ACI.

[1]  Hagen Schmal,et al.  Characteristic Complications after Autologous Chondrocyte Implantation for Cartilage Defects of the Knee Joint , 2008, The American journal of sports medicine.

[2]  R. Putz,et al.  Determination of knee joint cartilage thickness using three‐dimensional magnetic resonance chondro‐crassometry (3D MR‐CCM) , 1996, Magnetic resonance in medicine.

[3]  Albert C. Chen,et al.  Mechanical compression modulates proliferation of transplanted chondrocytes , 2000, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[4]  Leif E. Peterson,et al.  Advanced techniques in autologous chondrocyte transplantation. , 1999, Clinics in sports medicine.

[5]  J A Skinner,et al.  Autologous chondrocyte implantation versus matrix-induced autologous chondrocyte implantation for osteochondral defects of the knee: a prospective, randomised study. , 2005, The Journal of bone and joint surgery. British volume.

[6]  J A Skinner,et al.  A prospective, randomised study comparing two techniques of autologous chondrocyte implantation for osteochondral defects in the knee: Periosteum covered versus type I/III collagen covered. , 2006, The Knee.

[7]  U. Schneider,et al.  Klinische Drei-Jahres-Ergebnisse der matrixgekoppelten ACT zur Behandlung osteochondraler Defekte am Kniegelenk , 2008 .

[8]  W. Richter,et al.  Autologous Chondrocyte Implantation Using the Original Periosteum-Cover Technique versus Matrix-Associated Autologous Chondrocyte Implantation , 2010, The American journal of sports medicine.

[9]  B. Oakes,et al.  Reoperation after autologous chondrocyte implantation. Indications and findings. , 2004, The Journal of bone and joint surgery. British volume.

[10]  C. Clar,et al.  Autologous cartilage implantation for full thickness articular cartilage defects of the knee. , 2002, The Cochrane database of systematic reviews.

[11]  P. Lavigne,et al.  Autologous chondrocyte implantation: natural history of postimplantation periosteal hypertrophy and effects of repair-site debridement on outcome. , 2006, Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association.

[12]  G. Knutsen,et al.  Arthroscopic assessment of cartilage repair: a validation study of 2 scoring systems. , 2005, Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association.

[13]  Michael Sittinger,et al.  Treatment of posttraumatic and focal osteoarthritic cartilage defects of the knee with autologous polymer-based three-dimensional chondrocyte grafts: 2-year clinical results , 2007, Arthritis research & therapy.

[14]  Volkmar Jansson,et al.  Cell quality affects clinical outcome after MACI procedure for cartilage injury of the knee , 2009, Knee Surgery, Sports Traumatology, Arthroscopy.

[15]  F Eckstein,et al.  [Knee joint cartilage in magnetic resonance tomography. MR chondrovolumetry (MR-CVM) using fat-suppressed FLASH 3D sequence]. , 1995, Der Radiologe.

[16]  M. Brittberg,et al.  Two- to 9-Year Outcome After Autologous Chondrocyte Transplantation of the Knee , 2000, Clinical orthopaedics and related research.

[17]  T. Ackland,et al.  Clinical and Magnetic Resonance Imaging–Based Outcomes to 5 Years After Matrix-Induced Autologous Chondrocyte Implantation to Address Articular Cartilage Defects in the Knee , 2011, The American journal of sports medicine.

[18]  N. Ghanem,et al.  Classification of graft hypertrophy after autologous chondrocyte implantation of full-thickness chondral defects in the knee. , 2007, Osteoarthritis and cartilage.

[19]  U. Schneider,et al.  [Clinical results after three years use of matrix-associated ACT for the treatment of osteochondral defects of the knee]. , 2008, Zeitschrift fur Orthopadie und Unfallchirurgie.

[20]  J. Wasiak,et al.  Autologous chondrocyte implantation for full thickness articular cartilage defects of the knee. , 2010, The Cochrane database of systematic reviews.

[21]  F Eckstein,et al.  The morphology of articular cartilage assessed by magnetic resonance imaging (MRI) , 1994, Surgical and Radiologic Anatomy.

[22]  Marcus K. Taylor,et al.  Reliability and validity of the International Knee Documentation Committee (IKDC) Subjective Knee Form. , 2007, Joint, bone, spine : revue du rhumatisme.

[23]  B. Mandelbaum,et al.  Autologous Chondrocyte Implantation of the Knee: Multicenter Experience and Minimum 3-Year Follow-Up , 2001, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[24]  C. Ohlsson,et al.  Treatment of deep cartilage defects in the knee with autologous chondrocyte transplantation. , 1994, The New England journal of medicine.

[25]  E. Hunziker,et al.  Delamination rates of tissue flaps used in articular cartilage repair , 2000, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.