To explore the efficacy of three dimentional (3D) -printed porous titanium trabecular acetabular cups and traditional biological fixation acetabular cups in total hip arthroplasty (THA) for patients with type Ⅰ/Ⅱ acetabular dysplasia.

This retrospective cohort study included 70 patients with type I/II acetabular dysplasia who underwent THA at Guigang People's Hospital from September 2021 to September 2023. Patients were divided into two groups based on the type of prosthesis: the control group (n=35) received THA with a biological acetabular prosthesis, and the observation group (n=35) received THA with a 3D-printed porous titanium trabecular acetabular cup. The follow-up time, prosthesis survival rate, visual analogue scale (VAS) pain score, Harris hip score, prosthesis fixation effect, and safety were observed in both groups. The results of the above indicators were compared between the two groups. Independent sample t test was used for comparisons between groups for measurement data, paired ttest was used for comparisons within groups, and repeated measures ANOVA for the data at multiple time points. Chi square test or Fisher’s exact probability method were used for comparisons between groups for count data. The Mann-Whitney U test (non-parametric test) was used to compare the follow-up time between the two groups, and the log-rank test was used for comparison of survival curves between groups.

There was no statistically significant difference in VAS between the two groups (F=0.547, P>0.05), and there were statistically significant differences in both groups at three time points(control group F=386.724, observation group F=412.159, both P<0.001), while the difference in interaction effect of VAS score was also statistically significant ( interaction F=4.316, P=0.014). As for Harris scores, there was a statistically significant difference between the two groups (F=14.582, P<0.05), and statistically significant differences within both groups among the three time points (control group F=387.624, observation group F=425.817, both P<0.05). There was a statistically significant difference in interaction effect of the two groups (F=5.217, P<0.05). Multivariate analysis showed no statistically significant difference in Harris scores before operation between the two groups (t=0.403, P>0.05), but the observation group had higher Harris scores than the control group at three and six months after surgery (t=3.809, 4.521, both P<0.05). There was no statistically significant difference in follow-up duration between the two groups (P>0.05). The prosthesis survival rate of the observation group (100.0%) was better than the control group (97.1%) [ log-rank test hazard ratio (HR)=0.314, 95% confidence interval (CI) (0.013, 7.892), P<0.05].

3D-printed porous titanium trabecular acetabular cups can improve the clinical outcomes of THA in patients with type Ⅰ/Ⅱ acetabular dysplasia to a certain extent and are worthy of clinical promotion and application.