Femoral Rami and Obturator Nerve Trunk Block for Hip Surgery: A Critical Narrative Review

Background and Objectives: The femoral rami and obturator nerve trunk (FRONT) block combines iliopsoas-plane and subpectineal injections for anterior hip analgesia. This critical narrative review examines its anatomical rationale, clinical evidence, and motor implications. Materials and Methods: Targeted PubMed searches, supplementary Europe PMC retrieval, reference checking, and trial-registry records informed a structured narrative synthesis. The broader search was completed on 23 October 2026; the focused complete-FRONT PubMed search and registry checks were updated on 9 November 2026. Five directly relevant publications were assessed, with design-specific Joanna Briggs Institute (JBI) appraisal of the clinical reports. Results: One cadaveric study demonstrated femoral articular staining in 15 of 15 sides and combined femoral–obturator coverage in 13 of 15 sides from eight donors. Four uncontrolled clinical reports contained 14 patient descriptions; independence across reports could not be fully verified. Reported pain improvement and limited rescue-analgesic use provide preliminary feasibility observations, but co-interventions, absent concurrent controls, and inconsistent motor assessment prevent causal or comparative conclusions. Randomized component-block trials showed procedure- and comparator-dependent findings, including reduced adductor strength after subpectineal blockade; these findings cannot establish the effect of complete FRONT. Two registered comparative trials had no posted results at the update. Conclusions: FRONT has an anatomical rationale and preliminary feasibility evidence. Current evidence does not establish incremental analgesic benefit, preservation of both quadriceps and adductor function, improved recovery, or comparative safety, and does not support routine adoption in preference to established analgesic strategies. Procedure-specific controlled trials are needed to determine whether obturator addition provides a patient-important benefit.