The question of whether the HB is associated with higher complication rates than IA is still debated amongst A&E professionals today. The apprehension of transforming a closed fracture into an open fracture equivalent dates back to the 1980s, when R.D. Case amongst others described the theoretical risk of introducing an infection into the fracture site through the HB procedure [7,8,9].
Our findings show no difference in complication rates between HB- and IA-treated patients. Additionally, we were able to show that sex and type of fracture had no effect on minor, major or overall complications.
In 1991, Johnson and Noffsinger posed the question: ‘Haematoma block of distal forearm fractures. Is it safe?’ The prospective study found no signs of infection in patients treated with HBs. In their study the HB was compared to general anaesthesia and intravenous regional anaesthesia . In the years to follow, the HB rose in popularity amongst UK A&Es from 7% in 1989 to 33% in 1994, whereas the use of general anaesthesia for the closed reduction of distal radius fractures declined from 44 to 24% during the same time period. Main reasons named for the more frequent use of HBs in A&Es were the more efficient patient flow and reduced costs when compared to the more time-consuming and expensive general anaesthesia .
More publications followed that proved the efficacy of the HB and that demonstrated its greater pain control and higher rates of patient acceptance compared to other anaesthetic techniques [9, 13, 14].
In this study, we further demonstrate that patients suffering complications after distal radius fractures were significantly younger than those without complications. This result was independent of the type of analgesic method.
Interestingly, a prospective cohort study by Chung et al. found that increased age is a predictor for worse long-term outcomes, when measured one year after the surgical treatment of distal radius fractures, using volar locking plate systems . These contradicting results may be due to the fact that our patients were in general of older age and that the mean age of our patients suffering complications was rather close to that of our patients without complications (54.0 ± 16.8 years versus 61.3 ± 18.4 years). We therefore suspect this finding to be attributed to chance, especially because there was no significant age difference observed when major complications were analysed independently.
A recent study from 2016 showed that the HB proved to be especially effective in the elderly population. The HB group had therefore not only a significantly lower pain intensity compared to the general anaesthesia group during closed reductions but also a significantly lower duration of manipulation and a shorter time to discharge, which may be beneficial due to inherent comorbidities and higher rates of dementia . Similar data were gathered for the paediatric patient collective, where the length of stay in the A&E was also significantly shorter in the HB group in comparison to the procedural sedation group .
As with every invasive procedure, the HB method bears risks, which should be carefully evaluated and discussed with the patient prior to the intervention. Although our data did not show any cases of systemic neurological reactions, there have been case reports of seizures following HB procedures [11, 12]. The most probable cause for these seizures was an intravenous injection of the local anaesthetic. Aspiration of blood is usually a sign for intravascular penetration, and no injection should be performed in that case. Yet, aspiration of blood from a fracture haematoma is also a sign of a correct intra-fragmentary position of the needle through which the local anaesthetic is administered. Therefore, a C-arm image intensifier may be used in every HB procedure to reassure the physician of the needle’s correct position during the administration of the local anaesthetic. As there is only a small number of case reports on systemic effects of local anaesthetic following HB procedures, it is not a likely complication in daily practice, yet worth noting. Meinig et al. showed that plasma levels of lidocain after HB procedures were well below the toxic threshold when administered correctly and therefore systemic side effects of correctly administered HBs are unlikely .
Our data show two cases of local infections post-operatively. One case was observed in the HB and one in the IA group. The patient in the HB group did not show any signs of osteomyelitis and recovered fully after a single revision surgery. Unfortunately, we cannot make any assumptions about the patient in the IA group, as he was lost to follow-up before any further treatment. Posttraumatic osteomyelitis cases after closed distal radius fractures have been reported previously [20, 21], yet cases of osteomyelitis after distal radius fractures, which were reduced using a HB are rare. However, one case of a Staphylococcus aureus osteomyelitis after HB treatment was reported in the UK in 2002 .
Bearing these findings in mind, our aim was to assess the safety of the HB before the closed reduction of distal radius fractures in the A&E of a university hospital level-I trauma centre, treating between approx. 60000 and 65000 patients annually in 2012 and 2013. Proving our hypothesis, the HB group did not show higher major or minor complication rates in comparison to the IA group. Complications observed in the HB group also appeared in the IA group with a comparable incidence.
Complications like CRPS and local infections have been described as common complications after plate osteosynthesis treatment for distal radius fractures, regardless of the method of pre-procedural analgesia . The same applies to tendinitis, sensory and motor deficits, secondary dislocation, carpal tunnel syndrome, neuralgia and keloid formation, which were all reported to occur as complications after sustained distal radius fractures, independent of performed HBs [23,24,25]. It may therefore be that reported complications were due to the surgical intervention itself, rather than to the pre-operative HB procedure. However, since there was no difference in the occurrence of complications in either group, it can be stated that the HB is a safe method for the pre-surgical reduction of distal radius fractures. Limitations of this study were its mono-centric and retrospective character.