Tibial shaft fractures are common yet challenging to manage, with external fixation being a standard approach. This study aimed to compare functional recovery between two reduction and fixation techniques: traditional fluoroscopy-assisted external fixators and novel 3D-printed automatic reset splints.A retrospective analysis included 193 patients with open tibial shaft fractures treated between January 2021 and December 2024. Participants were divided into a traditional fluoroscopy-assisted (TF-A) group (n=104) and a 3D-printed automatic reset splint (3D-P) group (n=89). Reduction effectiveness was assessed using radiographic measurements (X, α, Y, Z, β) preoperatively and at 1 week, 1 month, 3months, and 6 months postoperatively. Healing status (callus formation and healing time), treatment efficacy, complication rates, knee function (HSS score), and pain intensity (VAS score) were evaluated during a 6-month follow-up.The 3D-P group demonstrated significantly better reduction across most deformity parameters (e.g., 1-week Y: 2.43±0.78 mm vs. 2.76±0.86 mm, P=0.006), shorter callus formation time (16.84±3.12 vs. 18.49±4.28 days, P=0.002), and faster fracture healing (72.97±10.93 vs. 78.26±15.33 days, P=0.006). Excellent efficacy rates were higher (69.66% vs. 51.92%, P=0.012), and total complications lower (20.22% vs. 33.65%, P=0.037). The 3D-P group also had superior knee function (HSS: 86.62±6.44 vs. 84.33±5.39, P=0.008) and lower pain VAS scores at all postoperative timepoints (e.g., 1 week: 4.93±0.86 vs. 5.37±1.02, P=0.002).Three-dimensional printed automatic reset splints offer significant advantages over traditional fluoroscopy-assisted fixation in improving reduction accuracy, accelerating healing, reducing complications, and enhancing functional recovery in tibial shaft fractures.