Intramedullary Nail Fixation by Suprapatellar and Infrapatellar Approaches for Treatment of Distal Tibial Fractures

Abstract

Objective: To compare the functional and alignment outcomes of intramedullary nail fixation using suprapatellar and infrapatellar approaches in treating distal tibial fractures.

Methods: In this retrospective study, 132 patients with distal tibial fractures (87 men, 45 women) ranging in age from 20 to 66 years were treated with intramedullary nails using the suprapatellar (69 patients) or infrapatellar (63 patients) approach. The radiographic alignment outcomes and ankle function were compared between the two groups. Multivariate logistic regression analyses were performed to determine which variety influenced ankle functional scores and whether the suprapatellar approach intervention demonstrated a protective effect.

Results: The mean follow-up time was 14.22 ± 2.31 months. The mean sagittal section angle of the fracture in the suprapatellar and infrapatellar approach groups was 3.20° ± 1.20° and 5.31° ± 1.23°, respectively (P < 0.001). The mean coronal section angle was 3.51° ± 0.89° and 5.42° ± 1.05°, respectively (P < 0.001). Three patients (4.3%) in the suprapatellar approach group and 15 patients (23.8%) in the infrapatellar approach group had poor fracture reduction (P < 0.001). The mean hind foot functional score and ankle pain score were 95.91 ± 4.70 and 35.91 ± 4.70 points, respectively, in the suprapatellar approach group and 85.20 ± 5.61 and 25.20 ± 5.61 points, respectively, in the infrapatellar approach group (P < 0.001 for both). In the comparison of ankle function, the multivariate logistic regression analyses demonstrated that the odds ratio in the suprapatellar approach group was about 7 times that in the infrapatellar approach group (odds ratio, 7.574; 95% confidence interval, 2.148-28.740; P = 0.002). Of the variants measured, the statistically significant risk factors for poor ankle function were AO type A3 (P = 0.016) and diabetes mellitus (P = 0.006). Sex and the operation interval were not statistically significant risk factors for poor ankle function.

Conclusion: Intramedullary nailing using the suprapatellar approach facilitates simple fracture reduction, excellent postoperative fracture alignment, and few complications, giving it obvious advantages over the conventional infrapatellar approach. Additionally, the suprapatellar approach is a prognostic factor associated with postoperative ankle joint function.

Fig. 1

(A, B): the antero‐posterior and lateral radiographs of typical distal tibia fracture with the distance from the main fracture line to the articular surface of distal tibia 35.5 mm. (C, D): the antero‐posterior and lateral radiographs immediate post operative showed the malalignment of sagittal plane 6.7° at the fracture site. (E, F): 6 months after operation, X‐rays showed bone healing with sagittal plane malreduction. (G, H): the intraoperative C‐arm images showed the displacement of distal fracture end in sagittal plane

Fig. 2

The suprapatellar approach and the position of lower limb

Fig. 3

(A, B): the antero‐posterior and lateral radiographs of typical distal tibia fracture with the distance from the main fracture line to the articular surface of distal tibia 40.5 mm. (C, D): the antero‐posterior and lateral radiographs immediate post operative showed anatomical reduction at the fracture site. (E, F): 6 months after operation, X‐rays showed bone healing without loss in reduction. G: the C‐arm image demonstrated suprapatellar approach. H: the antero‐posterior C‐arm image showed anatomical reduction in operation

Fig. 4

(A, B): the antero‐posterior and lateral radiographs of typical distal tibia fracture with the distance from the main fracture line to the articular surface of distal tibia 42.0 mm. (C, D): the antero‐posterior and lateral radiographs immediate post operative showed anatomical reduction at the fracture site. (E, F): 6 months after operation, X‐rays showed bone healing without loss in reduction. G: the C‐arm image demonstrated suprapatellar approach. H: the antero‐posterior C‐arm image showed anatomical reduction in operation