Description
Purpose: The aim of the study was to compare the clinical and functional outcome of patients after surgical treatment (intra-articular osteotomy (IO) vs. endoprosthetic knee replacement (ER)) of malunited tibial plateau fractures with a minimum follow-up (FU) of at least 24 months. We hypothesized that the outcome of IO was similar to the outcome of EG.
Methods: Between 2016 and 2021, all patients who underwent surgery due to malunited tibial plateau fractures in two national trauma centers (IO: n= 31; ER: n= 88) were included in the retrospective study. Patients with IO were matched to patients with ER with regard to initial fracture entity and gender. Clinical and functional results were collected with a follow-up period of at least 24 months.
Results: 20 patients with IO (11 men, 9 women, age: 45.6±11.2 years, FU 38.8±16.6 months) were matched to 20 patients with ER (11 men, 9 women, age: 60, 4±7.4 years, FU 41.4±19.3). At the time of the FU, the study population showed a significant reduction in pain (preoperative VAS 4.9 ± 2.1 vs. postoperative VAS 2.9 ± 1.9, p<0.001), as well as an increase in the Tegner activity score (preoperative 2.4 ± 1 points vs. postoperatively 3.3±1.5 points, p<0.001).
There were no differences between the groups with regard to postoperative pain (IO: 3.1 ± 1.8 vs. ER: 2.6 ± 2, p=0.463) or revision surgery (IO: 35% vs. ER: 55% p=0.204). 15% (n=3) of patients with IO converted to TEP over time.
In the ER group, postoperative limited loss of motion of the knee occurred significantly more often at the time of the FU (extension deficit 70% vs. 35%, p=0.027; flexion deficit
100% vs 50%, p<0.001). The postoperative Tegner activity score was significantly reduced in the ER group (2.7±1.1 vs. 3.9±1.6, p=0.009). The KOOS subscale sports activities was also significantly reduced in the ER group (26.1±21.9 vs. 46.1±26, p= 0.042), whereas the other four KOOS subscales, the clinical Rasmussen score or the Oxford Knee Score showed no significant differences. Linear regression analysis showed that the ER was a negative predictor of a reduced Tegner activity score regardless of patient age in comparison to the IO (OR -1.1, [95% CI, -2.1 to -0.12]; p= 0.028).
Conclusions: Surgical treatment of malunited tibial plateau fractures resulted in a significant improvement in activity level and pain reduction, regardless of whether the treatment was performed by endoprosthesis or intra-articular osteotomy.
In this patient population, patients treated with an endoprosthetic knee replacement showed significantly more often postoperative loss of motion of the knee and lower activity scores, independent of age. Patients with intra-articular osteotomy showed a relatively high risk of failure with 15% TEP conversion.
