E.12.1 Acute and Long Term harm
There are many tasks at sea that involve physical exertion, sometimes of large muscle groups but often of smaller groups undertaking repetitive tasks or maintaining awkward postures. A single severe episode of overloading can lead to an injury, commonly a sprain or strain. These events are best considered as injuries and safety management principles apply to their prevention.
However very often pain, swelling or other symptoms develop after repeated demanding actions have been performed and this is often somewhat delayed. Such problems, particularly those affecting the back and upper limbs, are among the commonest causes of temporary disabling illness among seafarers and they may sometimes lead to long-term limitations that can be career threatening. It can be difficult to distinguish the importance of work as a contributor to such problems, as musculo-skeletal pain is common and is often associated with aging or with other medical conditions. Physique and physical strength may also play a part in determining whether an individual presents with symptoms.
E.12.2 Risk assessment
Similar principles apply to these as for other health risks. However there are few reliable, quantified criteria that can be used to determine risk and preventative action is often initiated because cases have arisen in the past, either when particular tasks are performed or in other situations where similar demands are placed on the musculoskeletal system. The instability and slipperiness of decks and working surfaces on board is an additional risk factor at sea.
Common examples from seafaring include:
- Handling mooring cables and fuel lines, especially dragging them – back and limb pain
- Manual handling of food and technical stores, especially when stowing them in hard to access places – back pain
- Entry and movement through narrow confined spaces – variable joints and muscle groups
- Serving at table in the cruise industry – upper limb pain
- Moving passenger luggage in the cruise industry – back and joint pain
- Deck work in fish catching – back and upper limb pain, sometimes leading to termination of working life
- Fish processing on board – upper limb pain from gutting and filleting. Back pain from stowing frozen fish blocks
E.12.3 Risk management
There is little evidence that crew selection can reduce musculoskeletal risks, except in those with clear pre-existing disabilities. Reductions in work demands and recognition that these should be further reduced in adverse sea states contribute. Where possible, the use of mechanical aids to limit physical work demands should be adopted. Ergonomic assessment of particular tasks that are suspected contributors to pain will often identify practical solutions.
Case management has an important part to play in preventing the development of chronic pain and limitation of movement. Complete rest and avoidance of all manual tasks rarely helps. Acceptance that work is likely to have contributed to the problem is important as denial often leads to a confrontational situation that delays recovery. Active pain management, with non-sedating analgesics, should be started. As soon as recovery has begun a return to some duties but with reduced workload or avoidance of the heaviest tasks usually speeds full rehabilitation. The onboard medical guide may give advice on this, and TMAS or other clinical help should be obtained if there are severe or continuing symptoms.