Abstract: We included 31 trials (1760 participants; 897 randomized to peripheral nerve blocks and 863 to no regional blockade). Results of eight trials with 373 participants show that peripheral nerve blocks reduced pain on movement within 30 minutes of block placement (standardized mean difference (SMD) -1.41, 95% confidence interval (CI) -2.14 to -0.67; equivalent to -3.4 on a scale from 0 to 10; I2 = 90%; high quality of evidence). Effect size was proportionate to the concentration of local anaesthetic used (P < 0.00001). Based on seven trials with 676 participants, we did not find a difference in the risk of acute confusional state (risk ratio (RR) 0.69, 95% CI 0.38 to 1.27; I2 = 48%; very low quality of evidence). Three trials with 131 participants reported decreased risk for pneumonia (RR 0.41, 95% CI 0.19 to 0.89; I2 = 3%; number needed to treat for an additional beneficial outcome (NNTB) 7, 95% CI 5 to 72; moderate quality of evidence). We did not find a difference in risk of myocardial ischaemia or death within six months, but the number of participants included was well below the optimal information size for these two outcomes. Two trials with 155 participants reported that peripheral nerve blocks also reduced time to first mobilization after surgery (mean difference -11.25 hours, 95% CI -14.34 to -8.15 hours; I2 = 52%; moderate quality of evidence). One trial with 75 participants indicated that the cost of analgesic drugs was lower when they were given as a single shot block (SMD -3.48, 95% CI -4.23 to -2.74; moderate quality of evidence). High-quality evidence shows that regional blockade reduces pain on movement within 30 minutes after block placement. Moderate-quality evidence shows reduced risk for pneumonia, decreased time to first mobilization and cost reduction of the analgesic regimen (single shot blocks).

Plain-language summary: We included 31 trials (1760 adult participants: 897 randomized to peripheral nerve blocks and 863 to no regional blockade) performed in various countries and published between 1980 and 2016. Trials were funded by a charitable organization (n = 3), by a governmental organization (n = 1) or by departmental resources (n = 5), or did not specify the source of funding. Compared with other modes of analgesia, peripheral nerve blocks used to treat hip fracture pain reduce pain on movement better within 30 minutes (equivalent to a difference of -3.4 on a scale from 0 to 10 between the two analgesic regimens). The risk of pneumonia is also reduced when peripheral nerve blocks are used to treat hip fracture pain. For every 7 people with a hip fracture, one less person will suffer from pneumonia. Studies noted no major complications related to peripheral nerve blocks and reported reduced time to first mobilization after hip fracture surgery (approximately 11 hours earlier). We did not identify enough trial participants to determine if regional blockade makes a difference in terms of acute confusion, myocardial ischaemia and death within six months after surgery. Peripheral nerve block given as a single injection led to reduced cost of analgesic drugs. We rated the quality of evidence as high for reduction of pain on movement within 30 minutes, and as moderate for pneumonia, time to first mobilization and costs of analgesic drugs. We would need more information before we could draw final conclusions on effects of peripheral nerve blocks on the risk of acute confusional state, myocardial ischaemia and mortality.