Rapid Upper Limb Assessment (RULA)

Original Editor - Ajay Upadhyay

Top Contributors - Kim Jackson, Khloud Shreif, Ajay Upadhyay, Momina Khalid, WikiSysop and Amrita Patro

Development

Rapid Upper Limb Assessment method was developed by Mc Atamney and Corlett in 1993 as a survey method for use in ergonomics investigations of workplaces where work related back and upper limb disorders are reported. It is aimed to make a rapid assessment on neck and upper limb loading in mainly sedentary tasks.It is a method of semidirect assessment methods, used to know if the workers are exposed to musculoskeletal disorders during their work or not.

Purpose

The RULA ergonomic assessment instrument takes biomechanical and ergonomic load requirements related to occupational tasks/demands on the neck, trunk, and upper extremities into account. To assess the necessary repetition, power, and body position, a one-page worksheet is utilised.

Intended Population

RULA is a postural targeting method for estimating the risks of work-related upper limb disorders. A RULA assessment gives a quick and systematic assessment of the postural risks to a worker.

Method of Use

Positions of individual body segments will be observed and the more there is deviation from the neutral posture the higher will be the score of each body part.

The risk is calculated into a score of 1 (low) to 7 (high).

Categorization of body postures and force, with action levels for assessment

Assessment

The RULA method assess three key aspects:

• The posture of various body regions
• The amount of force or load exerted
• Muscle activity, whether during static posture or repetitive movements.

The evaluator gets ready for the assessment by interviewing the worker being evaluated to gain an understanding of the job tasks and demands, and observing the worker’s movements and postures during several work cycles. The selection of the postures to be evaluated should be based on:

• The most difficult postures and work tasks (based on worker interview and initial observation)
• The posture sustained for the longest period of time
• The posture where the highest force loads occur.

The RULA can be conducted quickly, so multiple positions and tasks within the work cycle can usually be evaluated without a significant time and effort. When using RULA, only the right or left side is assessed at a time, the side that suffers from the most harm. After interviewing and observing the worker, the evaluator can determine if only one arm should be evaluated or if an assessment is needed for both sides, and the body regions to be assessed divided into two groups: group A: arm, forearm, wrist and wrist turn and group B: neck, torso and legs. URLA assessment can be done in three ways: direct observation, or by capturing images or videos.

Score

Level	Score	Level of Risk
Level 1	1-2	negligible risk, no action needed
Level 2	3-4	low risk, change may be needed, measures should be taken, but not in the short term
Level 3	5-6	medium risk, further investigation, change soon, measures should be taken in short term
Level 4	6+	very high risk, implement change now

The final score is a relative score of risk, not an absolute score of risk.

Advantages

• Good for upper limb tasks, and repetitive tasks.
• Measuring musculoskeletal risks.
• Evaluating outcomes such as suitability of equipment and productivity.
• Great for educating workers around high risk postures.
• Good for tasks that are mostly static.
• Showing an objective number before and after interventions (useful for making the business case when presenting to colleagues or management).
• Reasonable accurate and reliable.
• Quick and easy to use.
• Has shown to improve productivity.
• Useful for presenting info to management (gives a number; is ‘objective’)
• Can compare pre- post- intervention
• Reasonably accurate and reliable
• Can demonstrate relationship between score and regional pain.

Disadvantages

• Tasks that involve the whole body.
• Wrist posture does not take into account position of function which has some wrist extension.
• Tasks that are varied.
• Does not take into account organisational and psychological factors.
• Occasional discrepancy of scores when limbs are at borders of two ranges.
• Difficult to catch with photograph. (Video is ideal)
• Limited to accessing one moment in time. Have to choose most extreme posture.
• May require several RULA assessments for one task.
• Not so good for tasks that involve the whole body and/or are varied.

Reliability

In adult RULA demonstrated higher intra-rater reliability than inter-rater reliability although both were moderate to good. RULA was also more reliable when used for assessing the older children (8-12 years) than with the younger children (4-7 years) when using computers. RULA may prove useful as part of an ergonomic assessment, but its level of reliability warrants caution for its sole use when assessing children, and in particular, younger children.

Resource

Guide: Rapid Upper Limb Assessment (RULA)

Ergoplus: A Step-by-Step Guide to the RULA Assessment Tool