We read with interest the randomised controlled trial by Buffoli et al. comparing different peripheral nerve blocks to enhance postoperative analgesia after total hip arthroplasty 1. Their study reflects the growing body of literature investigating the role of the lateral femoral cutaneous nerve (LFCN) block in this setting. There has been increasing attention on the LFCN block with the focus on motor-sparing analgesic strategies within enhanced recovery pathways. We searched for randomised controlled trials conducted in total hip arthroplasty in which the analgesic contribution of the LFCN block could be inferred and clinically relevant analgesic outcomes were reported. We identified nine trials published in the last five years, with comparators including wound infiltration; fascia iliaca-based techniques; erector spinae plane block; or the addition of LFCN blockade to pericapsular nerve group (PENG) block (Table 1). Analgesic outcomes were inconsistent and often comparable between groups. When differences were observed, they more frequently involved secondary endpoints (such as quadriceps strength, sensory distribution or time to ambulation) rather than primary pain scores or opioid consumption 1, 2. This pattern suggests that LFCN blockade may influence selected aspects of postoperative recovery without translating consistently into clinically meaningful improvements in pain control. Interpretation of these findings is further complicated by the heterogeneity of comparator techniques. In several studies, LFCN blockade was compared with strategies already providing effective cutaneous analgesia, such as wound infiltration or local infiltration analgesia, while in others it was added to comprehensive deep analgesic techniques addressing articular and peri-articular pain. In this context, the absence of a clear analgesic advantage should not necessarily be interpreted as a failure of LFCN blockade, but rather as evidence that its incremental contribution may be modest when baseline analgesia is already optimised. A critical and often underappreciated aspect emerging from this analysis is the surgical approach. Most of the included trials were conducted in patients undergoing total hip arthroplasty through a posterior approach, with only two studies regarding anterior approach. This observation has important anatomical implications. Sensory mapping has shown that the cutaneous territory covered by LFCN blockade is located too distally to cover the innervation of common posterior hip arthroplasty incisions fully 3. In contrast, the proximal portion of posterior incisions is innervated predominantly by the iliohypogastric and subcostal nerves, with only a limited and variable contribution from the LFCN 3. This anatomical mismatch offers a plausible explanation for the inconsistent and frequently modest analgesic signal observed in randomised trials evaluating LFCN blockade in posterior-approach total hip arthroplasty. These considerations are particularly relevant when interpreting trials comparing LFCN blockade with alternative cutaneous strategies, such as wound infiltration. In such settings, wound infiltration often provides superior early pain control, whereas LFCN blockade may offer comparable or slightly improved analgesia later in the first postoperative day, without clear superiority in functional recovery or opioid sparing 4. The timing of outcome assessment therefore becomes crucial when evaluating the true clinical relevance of LFCN blockade. Taken together, analysis of the available randomised evidence suggests that the LFCN block should not be regarded as a panacea for postoperative analgesia after total hip arthroplasty, particularly when a posterior surgical approach is used. While the technique remains attractive for its simplicity, safety profile and motor-sparing nature, its anatomical coverage is constrained in posterior-approach surgery. Future trials should stratify outcomes by surgical approach, define incision location and align the targeted cutaneous nerve blockade with the expected sensory territory, acknowledging that LFCN blockade may represent a supporting shot within a multimodal analgesic strategy rather than a standalone solution. At the same time, prolonging the duration of wound infiltration (e.g. using adjuvants or liposomal local anaesthetics) may help overcome the limitations of this approach. Appendix S1. References relating to Table 1. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Pascarella et al. (Thu,) studied this question.