Krackow suturing combined with the double-loop tension-reducing suture versus Kirschner-wire tension band for the treatment of inferior pole patella fracture

Background Inferior pole patellar fractures compromise the knee extensor mechanism and require stable fixation to permit early rehabilitation. Kirschner-wire tension band technique (KBW technique) remains widely used but is associated with fixation failure and implant-related complications, particularly in comminuted fractures. This study aimed to compare the clinical and radiological outcomes of the Krackow suturing combined with double-loop tension-reducing technique (KDL technique) with those of the conventional KBW technique for the treatment of inferior pole patellar fractures. Methods A retrospective comparative study was conducted involving 44 patients with AO/OTA type 34-A1 inferior pole patellar fractures treated between January 2022 and December 2024. Twenty-one patients underwent the KDL technique, and 23 patients were treated with KBW technique. Clinical outcomes included knee range of motion, Böstman score, complications, and reoperation rate. Radiological evaluation included the Insall–Salvati index (ISI) measured immediately postoperatively and at final follow-up. Statistical analyses were performed to compare outcomes between groups. Results Baseline demographic characteristics were comparable between groups. At final follow-up, the KDL group demonstrated significantly greater knee flexion (128.05 ± 3.23° vs. 119.56 ± 10.54°, P  = 0.001) and higher Böstman scores (28.52 ± 1.33 vs. 26.91 ± 2.30, P  = 0.015) than the KBW group. The final ISI was significantly higher in the KDL group (0.92 ± 0.14 vs. 0.78 ± 0.14, P  = 0.002), with a smaller postoperative decline in patellar height. The overall complication rate was significantly lower in the KDL group (9.5% vs. 39%, P  = 0.026), and no reoperations were required, compared with a 60.9% reoperation rate in the KBW group ( P  < 0.001). All fractures achieved union without infection or patellofemoral arthritis. Conclusions The KDL technique may provide stable fixation for inferior pole patellar fractures and was associated with improved postoperative knee flexion and lower complication and reoperation rates compared with the KBW technique.