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CHAPTER 8 • Fractures of the Distal Radius and Ulna

the early arrest. A small area of growth arrest in a patient near skeletal maturity may be clinically inconsequential. However, a large area of arrest in a patient with marked growth remain- ing can lead to ulnocarpal impaction and forearm deformity if intervention is delayed. MRI can map the area of arrest. 158 If it

is less than 45% of the physis, a bar resection with fat interpo- sition can be attempted. 124 This may restore radial growth and prevent future problems (Fig. 8-56). If the bar is larger than 45% of the physis, bar resection is unlikely to be successful. An early ulnar epiphysiodesis will prevent growth imbalance of the

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Figure 8-56.  Osseous bridge resection. A: This 10 year old had sus- tained a distal radial physeal injury 3 years previously and now com- plained of prominence of the distal ulna with decreased supination and pronation. B: Tomographs revealed a well-defined central osseous bridge involving about 25% of the total diameter of the physis. C: The bridge was resected, and autogenous fat was inserted into the defect. Growth resumed with resumption of the normal ulnar variance. Epiph- ysiodesis of the distal ulna was postponed for 6 months. D: Unfortu- nately, the radius slowed its growth, and a symptomatic positive ulnar variance developed. E: This was treated with an epiphysiodesis ( open arrow ) and surgical shortening of the ulna. The clinical appearance and range of motion of the forearm returned to essentially normal. (Courtesy of Children’s Orthopaedic Surgery Foundation.)

E