[Follow-up of fracture healing--indications and clinical relevance of direct radiographic magnification in comparison with conventional roentgen imaging].

Comparison of 83 magnification radiographs with corresponding conventional X-rays showed that direct radiographic magnification (DIMA) yielded additional information in 39 cases (47%), which had implications for the treatment in 19 cases (22.9%). In 11 cases callus was first visualized in magnification radiography; the earliest evidence of callus was found 14 days after surgery. Since magnification radiography means the region that can be examined is smaller, conventional radiographs were necessary in 32.5% of cases to find the position of the fracture in long bones. For statistical evaluation interobserver analysis was performed, anatomical and pathological structures being graded according to four levels. Magnification radiography proved superior in all structures examined. Magnification radiography can be recommended as an additional method to monitor fracture healing. Computed radiography was used together with magnification radiography to reduce the radiation dose and to perform image processing including simulation of conventional technique and edge enhancement. DIMA is a valuable tool in the evaluation of fracture stability and in the adjustment of distraction rates in limb-lengthening procedures.