Magnetic Resonance Imaging Osteonecrosis Pattern within an Osteochondral Dowel Allograft

ABSTRACT

A 22-year-old male with a history of a previously debrided large posttraumatic osteochondral lesion of the lateral femoral condyle presented to our institution for further treatment due to persistent pain and instability. He was treated with a large cryopreserved osteochondral dowel allograft and remained clinically asymptomatic with no pain, locking, or instability at his 12-month, 18-month, and 42-month follow-up appointments. However, his 12-month magnetic resonance imaging (MRI) examination demonstrated an osteonecrosis pattern within the osseous component of the allograft. Six months later, the osteonecrosis pattern decreased in size, and 30 months later had completely resolved. The allograft was otherwise stable in appearance. The MRI appearance was most likely due to a normal maturation process of bone healing within osteochondral allograft dowel, referred to as “creeping substitution.”

KEYWORDS

Osteochondral allograft - MRI - knee - osteonecrosis

REFERENCES

• 1 Görtz S, Bugbee W D. Allografts in articular cartilage repair.  J Bone Joint Surg Am. 2006;  88 1374-1384
• 2 Brown W E, Potter H G, Marx R G, Wickiewicz T L, Warren R F. Magnetic resonance imaging appearance of cartilage repair in the knee.  Clin Orthop Relat Res. 2004;  422 214-223
• 3 Sirlin C B, Brossmann J, Boutin R D et al.. Shell osteochondral allografts of the knee: comparison of MR imaging findings and immunologic responses.  Radiology. 2001;  219 35-43
• 4 Williams III R J, Ranawat A S, Potter H G, Carter T, Warren R F. Fresh stored allografts for the treatment of osteochondral defects of the knee.  J Bone Joint Surg Am. 2007;  89 718-726
• 5 Lexer E. Substitution of whole or half joints from freshly amputated extremities by free plastic operations.  Surg Gynecol Obstet. 1908;  6 601-607
• 6 Beltran J, Herman L J, Burk J M et al.. Femoral head avascular necrosis: MR imaging with clinical-pathologic and radionuclide correlation.  Radiology. 1988;  166(1 Pt 1) 215-220
• 7 Mont M A, Hungerford D S. Non-traumatic avascular necrosis of the femoral head.  J Bone Joint Surg Am. 1995;  77 459-474
• 8 Stoller D W, Li A E, Anderson L J, Cannon W D. The knee. In: Stoller DW Magnetic Resonance Imaging in Orthopedics and Sports Medicine. 3rd ed. Vol. I. Philadelphia; Lippincott Williams & Wilkins 2007: 692
• 9 Stoller D W, Sampson T, Bredella M. The hip. In: Stoller DW Magnetic Resonance Imaging in Orthopedics and Sports Medicine. 3rd ed. Vol. I. Philadelphia; Lippincott Williams & Wilkins 2007: 121-134
• 10 Kattapuram S V, Rosol M S, Rosenthal D I, Palmer W E, Mankin H J. Magnetic resonance imaging features of allografts.  Skeletal Radiol. 1999;  28 383-389