Metaphyseal fractures mimicking abuse during treatment for clubfoot

Background. Metaphyseal injuries resembling the classic metaphyseal lesion (CML) of abuse may occur as the result of serial casting during treatment o f clubfoot deformity. Mentioned in the orthopedic literature in 1972, this iatrogenic fracture has not been described in the radiologic literature nor has the similarity to injuries occurring with abuse been previously recogn ized. Objective. To describe the mechanism and radiographic appearance of metaphy seal injury observed during serial casting of clubfoot. Note similarities t o the CML of abuse. Materials and methods. Eight children ranging in age from 1 to 4 months und erwent casting for clubfoot. Five orthopedic surgeons from three different institutions performed the casting. Two patients had spina bifida and one, arthrogryposis. A complete skeletal survey was performed on one child who w as abused; there was no suspicion of abuse in the remaining seven. Results. All children manifest injury with periosteal new bone. One child h ad clear evidence of abuse with 24 rib fractures. X-rays of lower extremiti es in short leg casts revealed bilateral tibial metaphyseal fractures. Four other children had metaphyseal fractures resembling the CML of abuse, and three developed an area of sclerosis within the metaphysis. Conclusion. In the setting of serial casting for equinovarus deformity, met aphyseal injury even the CML of abuse may be noted. Since inflicted injurie s are almost always unobserved and explanations rarely offered, the fact th at the CML occurs as a result of orthopedic maniuplation may offer some fur ther insight concerning the pathogenesis of this well-described abuse injur y.