Comparison of direct anterior approach and posterior approach total hip arthroplasty: More than 5-year follow-up

Is There a Learning Curve for the 5-Year Implant Survival Rate of Total Hip Arthroplasty Using the Direct Anterior Approach With a Traction Table? A Prospective Cohort Study

BACKGROUND

The direct anterior approach (DAA) for total hip arthroplasty (THA) is attracting attention as a minimally invasive surgery, but the learning curve to master this approach is a concern, and its effect on long-term results is unknown. The purpose of this prospective cohort study was to clarify how the learning curve affects the 5-year results of DAA THA with a traction table.

METHODS

Of 402 THA cases using DAA with a mobile traction table and fluoroscopy, 249 cases composed of the first 50 cases for each surgeon were assessed during a learning curve, and 153 cases were evaluated after more than 50 cases of experience.

RESULTS

The 5-year-implant survival rate was 99.2% both during and after the learning curve. The 2-year complication rate in the learning curve group was 8.9 versus 5.9%, which was not statistically significant. The 2-to-5-year complication rates also did not differ between the cohorts (0 versus 0.7%). Both groups demonstrated decreased complication rates when comparing 2-year complications to 2-to-5-year complications. Clinical scores significantly improved by 2 years and were maintained at 5 years in both groups. The cup safe-zone success rates were 96.4% during the learning curve and 98.7% after the learning curve. The stem safe-zone success rates were 97.2% during the learning curve and 96.1% after the learning curve. Surgical time was approximately 20 minutes shorter after the first 50 cases than during the learning curve (70.8 versus 90.6 minutes, P = .001). Intraoperative blood loss was significantly less after the learning curve than during the learning curve.

CONCLUSIONS

This study implies that the learning curve affects perioperative results such as surgical time and intraoperative blood loss, but has little effect on short-term results up to 2 years after surgery and no effect on mid-term results from 2 to 5 years after surgery.

The influence of direct anterior approach and postero-lateral approach on wound complications after total hip arthroplasty: A meta-analysis

To date, we have reviewed the synthesis literature critically through four databases: PubMed, Embase, Cochrane Library and Web of Science. Eight relevant studies were examined after compliance with the criteria for inclusion and exclusion, as well as documentation quality evaluation. This report covered all randomised, controlled studies of total hip arthroplasty (THA) comparing the direct anterior approach (DAA) with the postero-lateral approach (PLA). The main result was surgical site infection rate. The secondary results were duration of the operation, length of the incision and VAS score after surgery. The results of the meta-analyses of wound infections in the present trial did not show any statistically significant difference in DAA versus PLA (between DAA and PLA) (OR = 1.42, 95%CI: 0.5 to 4.04, p = 0.51). Compared with PLA, DAA had shorter surgical incision (WMD = -3.2, 95%CI: -4.00 to -2.41; p < 0.001) and longer operative times(WMD = 14. 67, 95%CI: 9.24 to 20.09; p < 0.001). Postoperative VAS scores were markedly lower in DAA compared with PLA within 6 weeks of surgery (p < 0.05), with low heterogeneities(I2  = 0). We found that DAA did not differ significantly from PLA in terms of the risk of wound infection for THA and that the surgical incisions was shorter and less postoperative pain after surgery, even though DAA surgery takes longer.