Search our site 
Advanced Search
Home | Exam dates | Contact us | About us | Testimonials |


Bromage scale

Created: 30/11/2004
Updated: 25/1/2017

The perfect labour analgesic technique would provide complete pain relief with no motor block. Several studies have shown that epidural techniques utilising higher concentrations of local anaesthetic are associated with an increased incidence of instrumented vaginal delivery and a longer second stage of labour. It is commonly assumed that decreased motor function associated with higher concentrations of local anaesthetics causes these adverse outcomes. In addition, patients prefer less motor block; many parturients complain if they cannot move their legs, and some find it quite distressing. Some patients want to ambulate during labour or get up to use the bathroom without assistance. Those who do so may succeed in voiding, thus avoiding placement of a urinary catheter. For these reasons, obstetric anaesthetistss have developed, and continue to refine, analgesic techniques that minimise motor block.

The most frequently used measure of motor block is the Bromage scale. In this scale, the intensity of motor block is assessed by the patient's ability to move their lower extremities. The most significant shortcoming of the Bromage score in studies of labour analgesia is that it was designed to measure differences in surgical blocks, and is somewhat irrelevant to measuring motor block due to dilute local anaesthetic solutions for labour analgesia.

When using the Bromage scale for research in labour analgesia, it is important to measure motor block intermittently throughout labour, as the degree of block will change. It is also important to measure motor block in both legs, since the block may be asymmetrical.

Several modifications of the Bromage scale have been described, including the use of more gradations of motor block. For example, Breen et al. used a six-point scale to assess motor block. The value of this modification is in the differentiation of patients in the Bromage score IV category. 

Description of the Bromage score



Degree of block


Free movement of legs and feet

Nil (0%)


Just able to flex knees with free movement of feet

Partial (33%)


Unable to flex knees, but with free movement of feet

Almost complete (66%)


Unable to move legs or feet

Complete (100%)

Modified Bromage score as used by Breen et al




Complete block (unable to move feet or knees)


Almost complete block (able to move feet only)


Partial block (just able to move knees)


Detectable weakness of hip flexion while supine (full flexion of knees)


No detectable weakness of hip flexion while supine


Able to perform partial knee bend



[i] Bromage PR. Epidural Analgesia. Philadelphia: WB Saunders; 1978: 144

[ii] Epidural anesthesia for labor in an ambulatory patient.
Breen TW et al.
Anesth Analg 1993; 77: 919-24

SiteSection: Article
  Posting rules

     To view or add comments you must be a registered user and login  

Login Status  

You are not currently logged in.
UK/Ireland Registration
Overseas Registration

  Forgot your password?

All rights reserved © 2021. Designed by AnaesthesiaUK.

{Site map} {Site disclaimer} {Privacy Policy} {Terms and conditions}

 Like us on Facebook