Comparing outcomes for retrograde intramedullary nailing vs. antegrade intramedullary nailing for Femoral fractures - a systematic review and meta-analysis.

BACKGROUND

Distal femur fractures represent a small but clinically significant proportion of femoral injuries and are associated with high rates of complications, including non-union and revision surgery. Intramedullary nailing is a commonly employed fixation strategy, with both antegrade and retrograde approaches widely used in current practice. However, controversy persists regarding the optimal nail entry technique, particularly with respect to fracture healing, revision rates, and complications. This systematic review and meta-analysis aimed to compare clinical and radiological outcomes of antegrade versus retrograde intramedullary nailing for femoral shaft and distal femur fractures.

METHODS

This review was conducted in accordance with PRISMA guidelines and registered with PROSPERO (CRD420251274011). MEDLINE, EMBASE, and Cochrane databases were systematically searched for comparative studies evaluating antegrade and retrograde intramedullary nailing. Retrospective and prospective human studies reporting outcomes of union, revision, refracture, malunion, delayed union, operative time, and complications were included. Data extraction and quality assessment were independently performed, with risk of bias evaluated using the ROBINS-I tool. Meta-analysis was conducted using odds ratios (ORs) and weighted mean differences with 95% confidence intervals.

RESULTS

Five studies encompassing 1,479 patients were included, of whom 894 underwent antegrade nailing, and 585 underwent retrograde nailing. Antegrade nailing demonstrated a significantly lower rate of refracture following primary fixation compared with retrograde nailing (OR 31.41; 95% CI 4.45-221.80; p < 0.001). Revision rates were also significantly lower in the antegrade group (OR 1.76; 95% CI 1.21-2.58; p = 0.003). Retrograde nailing showed a higher overall union rate, although this did not reach statistical significance (p = 0.10). Rates of malunion, delayed union, non-union, operative time, and overall complications were comparable between groups, with moderate to substantial heterogeneity observed for several outcomes.

CONCLUSION

Both antegrade and retrograde intramedullary nailing provide effective fixation for femoral shaft and distal femur fractures. Antegrade nailing is associated with significantly lower rates of refracture and revision, while retrograde nailing demonstrates comparable union outcomes. These findings suggest that antegrade nailing may offer advantages in selected patient populations, particularly elderly individuals, although the surgical approach should ultimately be guided by fracture pattern, patient factors, and surgeon expertise.