Modified Multi-Strand Nice Knot Suture Construct Combined with Suture Anchor Fixation Versus Conventional Kirschner Wire Tension Band Fixation for Inferior Patellar Pole Fractures: A Retrospective Comparative Study.

Objectives

To compare the clinical efficacy of the modified multi-strand Nice knot suture construct combined with suture anchor fixation versus conventional Kirschner wire tension band fixation for inferior patellar pole fractures.

Methods

This retrospective chart review enrolled 108 consecutive patients with inferior patellar pole fractures treated surgically at our institution between January 2019 and January 2024. Patients were allocated to two groups based on the fixation method used: 52 patients underwent the modified suture construct fixation (modified suture fixation group, MSFG), and 56 received conventional Kirschner wire tension band fixation (conventional tension band fixation group, CTBFG). The primary outcomes included anterior knee pain VAS score, knee ROM, and complication rate; secondary outcomes comprised operative time, Bostman, Lysholm and Kujala scores, elective and symptomatic implant removal rates, time to fracture union, Insall-Salvati index, patellar length, and hospitalization costs.

Results

All surgical procedures were completed uneventfully. Baseline demographic and clinical characteristics were comparable between groups (all p > 0.05), with a mean follow-up of 25.5 ± 6.0 months (range, 22-36 months). Operative time did not differ significantly between cohorts (p = 0.230). Although the MSFG exhibited statistically lower anterior knee pain VAS scores (0.82 ± 0.6 vs. 1.26 ± 0.8, p = 0.003) and slightly greater knee ROM (132.7° ± 9.8° vs. 128.8° ± 8.1°, p = 0.027), the magnitude of these differences was below the recognized minimal clinically important difference. At the final follow-up, Bostman, Lysholm and Kujala scores were similar between groups (all p > 0.05). Of critical importance, the MSFG had markedly lower rates of implant-related complications and any secondary surgery (both p < 0.001). In the CTBFG, 40 patients (71.4%) underwent secondary surgery: 10 for symptomatic hardware irritation and 30 as entirely elective asymptomatic removals. By contrast, no patient in the MSFG required any form of reoperation. No revision surgeries for fixation failure were required in either group. Radiographically, fracture union time and patellar length were comparable (all p > 0.05). While the Insall-Salvati index was statistically lower in the MSFG (0.96 ± 0.1 vs. 1.02 ± 0.1, p = 0.006), all values remained within the normal physiological range and no functional impairment was observed. Subgroup analysis of comminuted fractures with osteoporosis demonstrated that the MSFG eliminated the implant failure complications seen in the CTBFG (0% vs. 28.6%).

Conclusions

The modified multi-strand Nice knot suture construct combined with suture anchor fixation provides functional outcomes equivalent to conventional Kirschner wire tension band fixation. However, it offers two distinct advantages: the complete absence of hardware-related complications and the elimination of the need for secondary implant removal. These findings suggest that the modified suture construct may offer particular advantages for patients with comminuted or osteoporotic inferior patellar pole fractures, although further prospective studies are warranted to confirm these observations.