Treatment of inferior polar fracture of patella with patellar claw combining tension band

Objective To report the clinical results of the treatment of inferior polar fracture of the patella with patellar claw combined with tension band. Methods From August 2008 to October 2014, 53 cases of inferior polar fracture of the patella treated in the department of orthopedics, the 184th Hospital of PLA were enrolled in the study, and cases of fracture at patellar body were excluded. The treatment of 28 cases used only tension band (the Kirschner wire group) ; the treatment of the other 25 cases used patellar claw combining with tension band (the patellar claw group). The comparison of the healing time postoperative complications and the function of knee joint in the last follow-up between the Kirschner wire group and the patellar claw group was carried out. Statistical analysis was performed using SPSS 13.0 software for data analysis, which applied independent sample t test for fracture healing time, the postoperative complications, and chi-square test for the knee joint function. Results All the cases were followed up for (12.5±2.9) months on average. The healing time of the patellar claw group [(9.7 ±0.9) weeks] was shorter than that of the kirschner wire group [(10.3±0.9) weeks]; the difference was significant(t=2.393, P <0.05). According to the Hospital of Special Surgery(HSS) scores, in the kirschner wire group, 10 patients recovered with excellent effect, nine patients with fine effect, seven patients with ordinary effect, and two patients obtained poor results; the fine rate was 67.9%. In the patellar claw group, 13 patients recovered with excellent effect, 10 patients with fine effect, one patients with ordinary effect, and one patients obtained poor results; the fine rate was 92%. The difference was significant (χ2=4.681 , P<0.05). In the Kirschner wire group, one case had traumatic arthritis, three cases occurred the internal fixation loosening, four cases occurred joint stiffness; in the patellar claw group, one case had traumatic arthritis, no internal fixation loosening was observed; the difference was significant (χ2=4.045, P<0.05). Conclusion The treatment of inferior polar fracture using the patellar claw combining tension band can achieve early knee joint function exercise and avoid joint stiffness, with satisfactory curative effect. Key words: Patella; Fractures, bone; Bone wires