VALIDITY OF THE PREOPERATIVE ANTHROPOMETRIC PARAMETERS FOR PROPER CHOOSING OF LENGTH AND DIAMETER OF THE TIBIAL NAIL IN COMPARISON WITH ACTUAL PARAMETERS TAKEN BY RADIOLOGICAL METHOD

Background: Tibial shaft fractures are common high-energy injuries that require precise implant selection to ensure stability, promote healing, and minimize complications. While intramedullary nailing is the gold standard of the management, accurate preoperative estimation of nail length and diameter remains challenging, often relying on intraoperative trial-and-error. Aim of the study: This study evaluated the accuracy of simple anthropometric and radiological measurements in predicting appropriate Tibial nail dimensions. Methods: A cross-sectional study was conducted from June 2024 to June 2025 in Basrah hospitals, Iraq, including 60 adult male patients with unilateral tibial shaft fractures. Preoperative measurements of the intact contralateral limb—Tibial tuberosity to joint line of the ankle-(TT-JL)—Tibial condyle-medial malleolus (TC-MM)—Tibial tuberosity-medial malleolus (TT-MM) and measurement of tibial canal diameter at the isthmus, were recorded and correlated with intraoperative measurements determined nail length and diameter. Statistical comparisons employed paired t-tests for length and Wilcoxon signed-rank tests for diameter, with accuracy assessed at ±10 mm and ±5 mm (length) and ±0.5 mm (diameter). Results: The tibial tuberosity–to–joint line (TT-JL) method yielded the smallest mean difference from intraoperative nail length (3.13 mm, p = 0.004) and the highest accuracy within ±10 mm (85%), outperforming Tibial Tuberosity-Medial malleolus (TT-MM) (80%) and Tibial Condyle-Medial malleolus (TC-MM) (76.67%) methods. Accuracy within ±5 mm was highest for Tibial Tuberosity-Medial malleolus (TT-MM) (68.33%), followed by Tibial Tuberosity to joint line of ankle (TT-JL) (66.67%) and Tibial Condyle-medial malleolus (TC-MM) (51.67%). Preoperative diameter estimates consistently underestimated intraoperative values (mean difference −1.29 mm, p < 0.001), with low precision (±0.5 mm accuracy: 16.67%). Mean operative time was 88.48 minutes, with a mean of 42.82 fluoroscopic exposures. Conclusion: Anthropometric measurements, particularly the TT-JL distance, can reliably estimate tibial nail length preoperatively, potentially reducing operative time and intraoperative adjustments. However, plain radiographic assessment of nail diameter remains unreliable, indicating the need for refined imaging protocols or advanced measurement tools. Standardizing preoperative length estimation methods could enhance surgical efficiency and safety in tibial shaft fracture management.