Digital planning of high tibial osteotomy. Interrater reliability by using two different software.

PURPOSE

The purpose of the study was to determine the interrater reliability as well as the correlation of mediCAD(®) and PreOPlan(®) in deformity analysis and digital planning of osteotomies.

METHODS

Digital radiographs were obtained from 81 patients planned to undergo an open wedge high tibial osteotomy. The JPEG files of the radiographs were imported to landmark-based software. Deformity analysis and planning of correction were performed by 1 experienced and 2 unexperienced observers. Osteotomy planning was aimed at correction to the predefined mechanical tibiofemoral angle of 3° valgus leg alignment. The interrater reliability of measurements was assessed using intraclass correlation coefficients (ICCs) and the confidence interval.

RESULTS

The ICC of PreOPlan(®) was from 0.841 (mechanical lateral distal femur angle) to 0.993 (wedge-angle) and from 0.896 (joint line convergence angle) to 0.995 (mechanical tibiofemoral angle) of mediCAD(®). The ICC of height of wedge-base was 0.979 with PreOPlan(®) and 0.969 with mediCAD(®). Comparing PreOPlan(®) and mediCAD(®), the ICC of the height of wedge-base of the observers was 0.966, 0.956 and 0.969, respectively.

CONCLUSIONS

The results show a high interrater reliability of digital planning software. Experience of the observer had no influence on results. Furthermore, a high interrater reliability and correlation of digital planning specific parameters was found. Surgeons need to master limb geometry measurements and osteotomy planning on digital radiographs as digital planning reports are used for intercolleagual correspondence, teaching purposes and as medicolegal documents. The digital planning software tested agrees with the actual demands and could be recommended for deformity analysis and planning of osteotomies.

LEVEL OF EVIDENCE

Diagnostic studies, Level I.