Received: 8 January 2001 Revision requested: 21 February 2001 Revision received: 6 March 2001 Accepted: 6 March 2001 W.B. Morrison, M.D. Department of Radiology, Thomas Jefferson University Hospital, 111 S. 11th Street, Philadelphia, PA 19107, USA S.E. Campbell, M.D., Capt USAF, MC Department of Radiology, Wilford Hall USAF Medical Center, Lackland AFB, Texas, USA B.J. Penrod, M.D., Major US Army Musculoskeletal Radiology, Brooke Army Medical Center, San Antonio, Texas, USA Abstract Objective. To describe the MR appearance following autoge- nous osteochondral “plug” transfer for the treatment of focal chondral defects of the knee. Design and patients. Twenty-nine 1.5-T MR knee studies including dynamic gadolinium enhancement were performed on 21 patients fol- lowing autogenous osteochondral “plug” transfer. Three musculoskele- tal radiologists retrospectively re- viewed images to evaluate graft and donor site appearance and MR find- ings were correlated with clinical outcomes. Results. MR images demonstrated graft protuberance (n=12/21; range 1–2 mm), depression (n=2/21; range 1 mm), and surface incongruity: mild (n=17/21), moderate (n=2/21), marked (n=1/21). The T2 signal of graft cartilage was similar to that of adjacent cartilage in 25 of 29 exam- inations, and increased in four. Graft cartilage thickness relative to adja- cent cartilage was <50% in six pa- tients, 50–100% in 15. Graft en- hancement in bone was absent at 2 weeks, but present at between 4 and 6 weeks following surgery. All patients had clinical follow-up ex- aminations and knee outcome survey scores were obtained in 15 patients with follow-up greater than 3 months after surgery. All patients demon- strated the expected short-term pro- gressive clinical improvement. Conclusion. MR images reveal a wide range of appearances following osteochondral “plug” transfer. Minor variations in graft orientation and surface congruity do not result in ad- verse clinical outcome in the short term. Keywords Cartilage, MR · Knee · Knee, surgery · Knee, MR · Surgery · MR Skeletal Radiol (2001) 30:570–578 © Int Skeletal Soc (ISS) 2001 ARTICLE Timothy G. Sanders Kurt D. Mentzer Mark D. Miller William B. Morrison Scot E. Campbell Brian J. Penrod Autogenous osteochondral “plug” transfer for the treatment of focal chondral defects: postoperative MR appearance with clinical correlation Work performed at Wilford Hall Medical Center, San Antonio, Texas, USA T.G. Sanders, M.D., Lt Col USAF, MC Deapartment of Radiology, The University of Texas, Health Science Center at San Antonio, Texas, USA T.G. Sanders, M.D., Lt Col USAF, MC Department of Radiology, Wilford Hall Medical Center, Lackland AFB, Texas, USA T.G. Sanders, M.D., Lt Col USAF, MC ( ✉ ) Department of Radiology, 759th MDTS/MTRD, 2200 Bergquist Drive, STE 1, Lackland AFB, TX 78236-5300, USA K.D. Mentzer, M.D., Capt USAF, MC Department of Orthopaedics, Wilford Hall USAF Medical Center, Lackland AFB, Texas, USA M.D. Miller, M.D., Lt Col USAF, MC Department of Orthopaedic Surgery, University of Virginia, PO Box 800753, Charlottesville, VA 22908-0753, USA Introduction Cartilage repair has been a topic of intense research over the past few years with several new surgical treatment options currently under investigation [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]. Procedures being utilized with varying degrees of success include abrasion arthroplasty, autologous chondrocyte transplant, microfracture technique, articu- lar cartilage transplant, fresh osteochondral allografts, and autogenous osteochondral “plug” transfers. Autoge- nous osteochondral “plug” transfer is a technique that utilizes small cylindrical plugs to repair articular carti-