Idiopathic facial palsy 2022

Inspired by Yang et al and Shi et al 2022.[1,2]

Scottish neurophysiologist Sir Charles Bell was the first author to describe the anatomical basis for facial paralysis, and has since served as the eponym for Bell’s palsy.

Bell’s palsy – idiopathic facial palsy
MA – manual acupuncture
EA – electroacupuncture
H-B – House–Brachmann (a grading system for facial palsy)
NMA – network meta-analysis (combines studies of different interventions to rank them in order of effect)
PNF – proprioceptive neuromuscular facilitation

key to acronyms

A patient with facial palsy came to see me for acupuncture this week. For years I avoided treating the condition with acupuncture because most cases resolved spontaneously, so it would have been difficult to know whether the treatment was effective. Then there was a landmark paper from 2013 (n=338) published in CMAJ demonstrating a clear effect of needling with manual stimulation of de qi (typical needling sensation) compared with the same protocol without stimulation.[3] The editor in chief of CMAJ was so impressed with the methods and results that he wrote an accompanying editorial titled Acupuncture – no sham, and suggested it was about time acupuncture became more mainstream.[4]

So, it was a bit disappointing to hear from my patient that all the doctors he had seen thus far had told him there was no evidence for the use of acupuncture. I guess that is not a huge surprise if you consider that the 3 consecutive Cochrane reviews on the subject all concluded that the quality of included trials was inadequate to allow any conclusion about the efficacy of acupuncture.[5–7] But they were all performed before the publication of the CMAJ trial in 2013, and there have been no updates since.

I was pleased to find that my patient had had 10 days of oral prednisolone, which had been started within a day or two of diagnosis. I did an ENT job on the late 80’s and then again in the mid to late 90’s. Steroids went from being used to not used and back to being recommended again. But the definitive trials were not performed until the 00’s.[8,9] These trials published in NEJM and Lancet Neurology were large (n=551 and n=839 respectively) and showed a definitive effect for prednisolone and a definite lack of effect for antivirals. I found it somewhat ironic that the some of the same doctors who dismissed the use of acupuncture were happy to advocate ineffective and expensive antivirals.

Checking the various recovery rates in these big trials with those in the subsequent CMAJ acupuncture trial, I was a little concerned that the success rate in the control group of the latter was a little low by comparison. I found a more recent paper studying prognosis, and realised that the timing of recruitment and therefore initiation of steroids was critical.[10]

So, I’m more than halfway through the blog and I have not mentioned the papers I am highlighting yet! The first popped up this week on my searches and because I had facial palsy in mind, I was more motivated to look at it. It is retrospective observation study on treatment outcomes in idiopathic facial palsy (Bell’s palsy) from a single centre in Guangzhou and published in Frontiers in Neurology.[1] The cases identified were divided into two groups based on whether or not acupuncture treatment was initiated within 7 days of onset of the palsy. Propensity score matching was used to create comparable cohorts who either had MA/EA or EA alone. The MA/EA group were those where the treatment was initiated within 7 days of onset of the palsy. EA was used in both groups after 7 days. Presumably this is what is done in routine practice in this centre, and perhaps more widely in China.

Importantly this retrospective cohort included only patients with an H-B grade of IV or worse (moderately severe asymmetry and incomplete eye closure),[11] and the propensity score matching included the time of onset of oral steroids (within 72 hours or not).

345 patients were included initially, and this was reduced to 61 in each group after propensity score matching. The outcome was assessed at 6, 12 and 24 weeks. By 24 weeks the full recovery rate was 93% in the early onset treatment group and 84% in the later onset treatment group. The difference was statistically significant at 12 weeks (93% vs 80%) with a strong but non-significant trend at 6 and 24 weeks.

The second paper I am highlighting also comes from Frontiers in Neurology, but earlier in 2022, and it is an NMA of both drug and physical treatments for Bell’s palsy.[2] A total of 26 studies representing 3609 patients undergoing 15 different treatments were included.

Treatment combinations came out on top, and acupuncture plus electrical stimulation was second on the list after steroids plus antivirals plus Kabat treatment. I was curious about the phrase ‘acupuncture plus electrical stimulation’, so I checked the references and found that this was in fact EA, or more accurately a combination of MA plus EA.[12]

Antivirals are still listed and used everywhere despite the lack of effect. The majority of the drug trials use a combination. I was amused to note that in the results grid for the NMA, antivirals are at the bottom… even below placebo!

But what about Kabat treatment I hear you exclaim… yes I checked that out as well, and I am glad I did! This treatment is now more commonly referred to as PNF, and Herman Kabat (1913–1995) was a neurophysiologist. He was keen to take the contemporary findings of basic research into the neuromuscular system and apply it in clinical rehabilitation. He particularly followed the Nobel Laureate Charles Scott Sherrington, a fellow neurophysiologist, whose work emphasised the complex relationships of the neuromuscular system including reciprocal innervation and inhibition.

If you want to read more about Herman Kabat, I can recommend a paper from 2013 in the journal Physical Medicine and Rehabilitation by Elizabeth Sandel.[13]

References

1          Yang L-S, Zhou D-F, Zheng S-Z, et al. Early intervention with acupuncture improves the outcome of patients with Bell’s palsy: A propensity score-matching analysis. Front Neurol 2022;13:943453. doi:10.3389/fneur.2022.943453

2          Shi J, Lu D, Chen H, et al. Efficacy and Safety of Pharmacological and Physical Therapies for Bell’s Palsy: A Bayesian Network Meta-Analysis. Front Neurol 2022;13:868121. doi:10.3389/fneur.2022.868121

3          Xu S, Huang B, Zhang C, et al. Effectiveness of strengthened stimulation during acupuncture for the treatment of Bell palsy: a randomized controlled trial. CMAJ 2013;185:473–9. doi:10.1503/cmaj.121108

4          Fletcher J. Acupuncture–no sham. CMAJ 2013;185:459. doi:10.1503/cmaj.130319

5          He L, Zhou D, Wu B, et al. Acupuncture for Bell’s palsy. Cochrane Database Syst Rev 2004;1:CD002914. doi:10.1002/14651858.CD002914.pub2

6          He L, Zhou MK, Zhou D, et al. Acupuncture for Bell’s palsy. Cochrane Database Syst Rev 2007;4:CD002914. doi:10.1002/14651858.CD002914.pub3

7          Chen N, Zhou M, He L, et al. Acupuncture for Bell’s palsy. Cochrane Database Syst Rev 2010;8:CD002914. doi:10.1002/14651858.CD002914.pub5

8          Sullivan FM, Swan IRC, Donnan PT, et al. Early treatment with prednisolone or acyclovir in Bell’s palsy. N Engl J Med 2007;357:1598–607. doi:10.1056/NEJMoa072006

9          Engström M, Berg T, Stjernquist-Desatnik A, et al. Prednisolone and valaciclovir in Bell’s palsy: a randomised, double-blind, placebo-controlled, multicentre trial. Lancet Neurol 2008;7:993–1000. doi:10.1016/S1474-4422(08)70221-7

10        Urban E, Volk GF, Geißler K, et al. Prognostic factors for the outcome of Bells’ palsy: A cohort register-based study. Clin Otolaryngol 2020;45:754–61. doi:10.1111/coa.13571

11        House JW, Brackmann DE. Facial nerve grading system. Otolaryngol – Head Neck Surg 1985;93:146–7. doi:10.1177/019459988509300202

12        Liu L-A, Zhu Z-B, Qi Q-H, et al. [Comparison of therapeutic effects of peripheral facial paralysis in acute stage by different interventions]. Zhongguo Zhen Jiu 2010;30:989–92.

13        Sandel ME. Dr Herman Kabat: neuroscience in translation… from bench to bedside. PM R 2013;5:453–61. doi:10.1016/j.pmrj.2013.04.020


Declaration of interests MC

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