Occupational Back Injuries During Manual Handling of Material

INDEX PAGE

INTRODUCTION 3

ERGONOMICS 4

OBJECTIVES OF ERGONOMICS 4

RESULTS OF ERGONOMIC APPLICATIONS 5

THE BACK STRUTURE 6

BACK AND BACK PROBLEMS 6

Back injuries 6

Causes of back injuries 7

The following are common causes of back injuries:- 7

Back injury prevention 8

Back injury-preventative techniques 8

Techniques 9

Strategies 9

ORIGINAL LIFTING MODEL 10

Strain index (SI) = 10

Action limit 11

Maximum permissible limit 11

Administrative controls 12

Engineering controls 12

Limitations of the NIOSH lifting model 13

LEGISLATIVE TRENDS: STANDARDS, GUIDELINES AND INTERVENTION PROGRAMMES 13

CONCLUSION 14

APENDIX 1 15

REFERENCES 16

OCCUPATIONAL BACK INJURIES DURING MANUAL HANDLING OF MATERIAL

INTRODUCTION

Almost one third of all disabling injuries at work, temporary or permanent are related to manual handling of objects. Many of these incidents are avoidable and are the consequence of inadequate or simplistic bio-mechanical task analysis.

Injuries associated with manual materials handling have grown substantially and are currently estimated to exceed several billion dollars annually in the USA. In addition to the compensation costs are the tremendous costs associated with the suffering of the impaired workers.

Manual material handling injuries can result from lifting, lowering, pushing, pulling or carrying objects while performing activities .

Some of the most traumatic and costly manual material handling injuries impact on the back, more specifically the lower back has been the area of concern in most studies examining the low back pain associated with manual material handling.

Lifting, handling and dragging loads involve a good deal of static effort, enough to classify as heavy work. The main problem with these forms of work however is not the heavy loads on the muscles, but much more the wear and tear on the intervertebral disks with the increased risk of back troubles.

Back troubles are painful and reduce one's mobility and vitality they lead to long absence from work, and in modern times are among the main causes of early disability .

ERGONOMICS

Ergonomics is concerned with the design of systems in which people carry out work. Its name comes from the Greek words ergon which means "work" and monos which means "law". All work systems consist of a human component and a machine component embedded in a local environment.

When designing any system where humans and machines work together to produce something, we need to know about the characteristics of the people involved and be able to apply this knowledge to the design. This activity is the fundamental function of ergonomics.

Ergonomics came about as a consequence of the design and operational problems presented by new work systems which had evolved with the advance of technology. It owes its development to the same historical processes, which gave rise to the to other work system disciplines such as industrial engineering and occupational medicine.

The practice of ergonomics requires that knowledge about human anatomy, physiology, and psychology be applied to the design of work systems. Particular emphasis is placed on the design of the human - machine interface to ensure increased safety and usability of equipment and the removal of harmful stressors.4

OBJECTIVES OF ERGONOMICS

Ergonomics deals with the interaction between human and machine in the work environment. The main objective of ergonomics is to achieve an optimal relationship between people and their work environment.

The two conflicting factors in this optimisation process are workers productivity and their health and physical wellbeing. That is, while workers should perform their job in the most efficient manner possible, they must also be protected against undue physical and psychological strain that may occur as a result of performing the required task.2

RESULTS OF ERGONOMIC APPLICATIONS

The following are some expected outcomes of applying the principles of ergonomics to the workplace:

* Understanding the effects of a particular type of work on workers bodies and their job performance.

* Predicting the long-term or cumulative effects of work on their job performance.

* Assessment of fitness of the workplace and or tools to workers in performing a job.

* Improvement of productivity and wellbeing of workers by "fitting the task to the person, or fitting the person to the task". The result of such efforts is to achieve the best match between worker capabilities and job requirements.

* Establishment of knowledge based support for designers, engineers and medical personnel for improving the productivity and wellbeing of individuals.2

THE BACK STRUTURE

The back is a complex structure that is made of:

Muscles

Bones (vertebrae and their processes)

Ligaments

Tendons

Blood supply

Spinal and branched nerves

The vertebrae are separated by the intervertebral disks. An intervertebral disk is a tough fibrous ring resembling a sac that is filled with a viscous fluid (gel like substance). These disks act