The Correlation Of Various Anthropometric Measurements With Tibia Interlocking Nail Length Measured Intra-Operatively

Abstract

Background: A proper and accurate size of tibial nail insertion is necessary for better functional outcome and to prevent complications related to improper nail length. Various preoperative and intraoperative measures are used, with varied accuracy for nail size estimation. With aim to find out the best anthropometric measure correlating with the tibial nail length, we correlated various anthropometric measurements to actual size of tibial interlock nail used in 100 cases of tibial shaft fracture.

Material & Methods: 5 anthropometric parameters were measured i.e. (1) distance from medial knee joint line to ankle joint line (K-A) (2) distance from medial knee joint line to medial malleolus (K-MM) (3) distance from tibial tuberosity to ankle joint (TT-A) (4) distance from tibial tuberosity to medial malleolus (TT-MM) (5) distance from tip of olecranon to 5th metacarpal head (O-MH) in 100 cases of tibial shaft fractures treated with interlocking nail and were correlated with the tibial nail size used. 

Results: Mean size of nail used was 33.61±1.69 mm (range 28 to 36 mm). Mean of five anthropometric parameters for K-A, K-MM, TT-A, TT-MM and O-MH, were 35.61±1.59 (range 30 to 39 mm), 37.16 +1.36 (range 32 to 41.5 mm), 33.58 ± 1.79 (range 28 to 37 mm), 34.40 ± 1.21 (range 30 to 39 mm), and 33.10 ± 1.61 (range 28 to 36 mm) respectively.

Conclusion: All anthropometric parameters i.e. TT-A, TT-MM, K-A, K-MM and O-MH can be used for nail size prediction. O-MH was nearly accurate to the nail size as compared to other methods because of interpersonal variation in palpation of tibial tuberosity.