Analgesic efficacy of local versus proximal nerve blocks after hallux valgus surgery: a systematic review

Hallux valgus (HV) surgery is an orthopaedic procedure that commonly causes mild to moderate postoperative pain. Effective management of this pain has become an important element of modern hallux valgus surgical treatment. A local anaesthetic (LA) with an antinociceptive effect can control this pain. However, relatively few papers have evaluated this strategy in depth. The objective of the current systematic review was to address this demand by comparing the efficacy of proximal and local blocks in controlling postoperative pain following hallux valgus surgery.

Ovid-MEDLINE, Cochrane Central, PubMed, Web of Science (WOS), Scopus, and Embase were searched from their inceptions through December 29, 2021. Observational and clinical trial publications in peer-reviewed English-language journals with a sample size of at least 20 were included. The trials involved adults over 18 who could describe their discomfort and had a bunionectomy. The included studies were evaluated using the Cochrane risk of bias 2 method. Descriptive analysis synthesised the results. Among the 439 articles identified, five studies compromising 459 participants were included. Ankle blocks were superior to control in two studies (P = 0.001, P < 0.001) and superior to local blocks in one study (P < 0.001). Additionally, one study showed that popliteal and ankle blocks administered with lidocaine or levobupivacaine were equivalent (P = 0.123 and P = 0.055, respectively). However, one of these five included studies indicated that ankle blocks were not effective (P = 0.123) in reducing postoperative pain.

The key findings presented herein suggest that regional blocks effectively reduce postoperative pain and that an ankle block has more supportive evidence for its effectiveness. However, an adequate assessment of the effectiveness of various administrative routes was challenging due to the lack of reliable evidence. This needs to be addressed in future studies.

PROSPERO registration: CRD42022307974.