Tackling the resurgence in mumps
RSI requires a diagnosis of exclusion. Professor Howard Bird and Kiran Hussain advise on options for investigation and management
Much can be learned about RSI from musicians. They are often self-employed and ineligible for compensation and so have a big incentive to return to work. If a careful history suggests a close correlation between an increased ergonomic load and the onset of symptoms characteristic of that load, the diagnosis of an 'overuse' syndrome can be made with reasonable confidence.
In factory workers, a careful miming of the occupation and note of the time spent working will allow assessment of the periods involving pinch grip (risk of overuse of the tendons to the thumb), rotational torque (risk of epicondylitis) or heavy lifting at head height (risk to the shoulder). If the ergonomic insult linked with the symptoms can be identified, the first aid is to remove it from the workplace until such time as natural recovery occurs.
Unfortunately, symptoms related to everyday tasks such as keyboard and mobile phone use do not always allow such easy analysis.
History and examination
Since 'RSI', if it exists, is a diagnosis of exclusion history is essential. Cardinal symptoms of arthritides that might mimic problems such as early rheumatoid arthritis, lupus and cervical spondylosis with referred pain to the hand should be sought. Typical symptoms that might delineate a localised tenosynovitis such as de Quervain's, a carpal tunnel syndrome or an epicondylitis as a contributing factor to existing symptoms or even as a work-induced complaint, should be sought.
However, in the absence of such features, with symptoms such as discomfort or pain or even paraesthesia on working, suspicion now points to the workplace and a detailed ergonomic history is required. An increase, gradual or sudden, in the total amount of work performed per unit time is always suggestive. A specific change in the working practice with an onset of symptoms within a few weeks, in the absence of any hobbies that might have precipitated them instead, becomes highly suggestive.
Careful examination is required to exclude conditions that mimic, as already mentioned.
A general examination is also required for features that might place individuals at slight constitutional risk. We have the impression that those with 'average' build are less likely to encounter overuse syndromes than those who are short and fat or long and thin. This particularly applies to the shape of the digits. A slight thoracic scoliosis often previously undetected undoubtedly predisposes to upper arm problems in the workplace. We also have the impression that individuals with hyperlax joints may be particularly susceptible, presumably because extra muscular effort is required to maintain them in the physiological position of neutrality before work commences.
Normal acute phase reactants will exclude inflammatory arthritis and muscle enzymes are invariably normal. ANF and rheumatoid factor will tend to exclude specific diseases; an X-ray of the hand and wrist may exclude localised osteoarthritis as a contributor to symptoms and will assist in the exclusion of inflammatory arthritis. Pain is often accompanied by 'numbness' and if paraesthesia predominates (and certainly if there are clinical and neurological signs), nerve conduction studies are likely to be helpful. These should be complemented by an X-ray of the cervical spine to detect possible nerve root compression.
If a work-related upper limb disorder is thought to be the diagnosis, whether caused by overuse or a sudden change in technique or both, rational management is directed in the first place at patient education and avoidance of the task that caused the problem. This does not necessarily mean complete cessation of work. Sometimes a modification of the job, just to exclude the proportion of time spent in, say, pinch grip will alleviate symptoms.
If such precision in work is not possible, transfer to a different task may be helpful diagnostically and therapeutically.
For keyboard users the amount of keyboarding should redistributed equally throughout the working day. The patient should pay attention to position of the keyboard, the chair, the stretch required, the position of the forearms and the ergonomic qualities of the mouse.
If simple modifications of this sort fail to help, a longer period off work, perhaps one or two weeks, might be tried. If the patient is still unable to return, specialist help might then be sought. By this stage, any occupational health service is also likely to be involved.
Most overuse problems seem to resolve spontaneously with time providing the predisposing factor is identified and removed, normally for a period of weeks or months. Hobbies might aggravate things and should be avoided. Musicians playing several instruments may need to switch to the one that troubles them least.
The danger is that once the first improvement is noted, the patient dashes back to their previous habits. It is safer to advise a cautious return over a period of perhaps three to six months in the knowledge that a proportion will take two years to settle and a small group, who become chronic, may take even longer. In general, the shorter the history the speedier the recovery. Patients who have 'battled on' for two years may face a five-year path to improvement.
Analgesics may relieve symptoms but should not be allowed to mask them with the risk of premature return to work. Non-steroidal anti-inflammatory drugs are less rational in this situation but occasionally help. Topical application of analgesics or counter-irritants might assist and many patients gain benefit from a small nocturnal dose of amitriptyline or dothiepin.
Onward referral can be quite difficult. Orthopaedic surgeons have greatest expertise in the management of obvious pathology but should certainly be considered if the median nerve in carpal tunnel syndrome might need decompressing, or if steroid injections are not done at the surgery.
Sports medicine specialists, rheumatologists and musculoskeletal physicians have considerable experience.
Many patients find Pilates helpful, which seems to strike the correct balance between relaxation and the modest exercise needed to avoid disuse atrophy.
The scientific basis for overuse remains hypothetical and controversial in the lack of adequate research investment in this economically important area.
What I tell patients
·The condition you have afflicts a small proportion of the population and has done for centuries
·The anatomy you have inherited sometimes predisposes
·Ergonomic factors either at work or through hobbies are usually the main cause
·Rest will relieve your symptoms
·Even more important, the correction of the ergonomic factors that have predisposed will assist recovery and reduce the risk of recurrence
·Providing this is done, the condition normally settles but may take a couple of years to resolve completely, particularly if it is well established
·Drug treatment is of limited value though ergonomic assessment, physiotherapy (provided not too vigorous) and relaxation techniques may all assist
Howard Bird is professor of pharmacological rheumatology, University of Leeds, and
Kiran Hussain is intercalated BSc student, University