Investigations in Work-Related Upper Limb Disorder Claims: Part 1 – Carpal Tunnel Syndrome

GENERAL BACKGROUND TO WRULD CLAIMS

The term ‘upper limb disorders’ (ULD’s) is a general label used to refer to a range of medical conditions affecting the upper limbs which occur commonly within the general population.

The term ‘upper limb’ refers to:

  1. The part of the body: the arm and hand, covering a region extending from the tips of the fingers to the shoulder and extending into the neck.
  2. The tissues: the soft tissues, muscles and connective tissues (tendons and ligaments) and the bony structures, as well as the skin, along with the circulatory and nerve supply to the limb.

ULD’s can be described by the part of the body affected, or by the presumed pathological mechanism.

The most common ULD’s encountered are:

  • Carpal Tunnel Syndrome (covered this week in Part 1);
  • Shoulder Injuries (rotator cuff tendonitis, rotator cuff tears and Shoulder Impingement Syndrome) (covered next week in Part 2);
  • Epicondylitis [both lateral (Tennis Elbow) and medical (Golfer’s Elbow)] (covered next week in Part 2);
  • De Quervain’s Disease (Blackberry Thumb) (covered in edition 251 in Part 3); and
  • Stenosing Tenosynovitis (Trigger Finger) (covered in edition 251 in Part 3).

These conditions are typically self-limiting in terms of their duration and typically have good prognosis. They can resolve with rest, non-invasive treatments, such as splints and wrist supports or with steroid injections and in some cases surgery.

Some of these ULDs have an association with work activities, so they may, in some cases, be caused by work or aggravated, exacerbated or their onset accelerated by the same. In such cases they are referred to as Work Related Upper Limb Disorders (WRULDs).

Features of occupational tasks that are typically considered to be connected to WRULD’s include:

  • Repetition;
  • Force;
  • Duration of exposure;
  • Awkward posture;
  • Working environment;
  • Psychosocial factors; and
  • Individual differences.

These are described below.

Repetition

Work is repetitive when it requires the same muscle groups to be used over and over again during the working day or when it requires frequent movements to be performed for prolonged periods.

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(Source: Pxhere)

Force

Force can be applied to the muscles, tendons and joints of the spine by handling heavy objects, performing tasks such as pushing and pulling, fast movements or as a result of excessive force generated by the muscles of the body.

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(Source: Flikr)

Duration of Exposure

Duration refers to the length of time for which a task is performed. It includes the length of time that the task is undertaken in each shift, plus the number of working days the task is performed (e.g. four hours per day, five days per week). Short exposures are unlikely to create significant risk of injury, except where the task is exceptionally demanding and/or the worker has not been allowed to build up to its demands over a period of time. This can occur after returned to work from holidays always an increase in the work pace.

Working Posture

Working postures can increase the risk of injury when they are awkward and/or held for prolonged periods in a static or fixed position. An awkward posture is where a part of the body is used well beyond its neutral position. A neutral position is where the trunk and head are upright, the arms are either side of the body, forearms are hanging straight or at a right angle to the upper arm, and the hand is in the handshake position. Static postures occur when a part of the body is held in a particular position for extended periods of time without the soft tissues being allowed to relax.

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(Source: Wikimedia Commons)

Working Environment

This includes factors such as vibration, cold and lighting.  Exposure to cold and resulting decreased blood flow, decreased sensation dexterity, decreased maximum grip strength and increased muscle activity. The visual demands of the task are an important consideration since the workers posture can be largely dictated by what they need to see.

Psychosocial Factors

Examples include workers who have little control over their work and work methods, where work demands are perceived to be excessive or there is a payment system in place which encourages working too quickly or without breaks.

Individual Differences

Examples include new workers who may need time to acquire the necessary skills and/or rates of work, differences in competence and skill, workers of varying body size (weight, height, reach), vulnerable groups (older workers, younger workers, expectant mothers), health status and disability, individual attitudes or characteristics.

This week, we provide a background to carpal tunnel syndrome and composite template schedule of investigations for WRULD claims.

BACKGROUND TO CARPEL TUNNEL SYNDROME (CTS)

Introduction

Carpal Tunnel Syndrome (CTS) is a condition caused by irritation to the median nerve within the wrist. 

In the UK, approximately 3 in 100 men and 5 in 100 women experience CTS in their lifetime, according to the NHS[i], making it one of the most prevalent ULDs.  Most studies report population prevalence of 1-5 %.  It can affect people of all ages, though it tends to become more common with age, with those aged 45 to 65 most likely to be affected.  It is the most common nerve compression disorder.  A US study[ii] found that incidence of CTS has increased during and since the 1980s.

The carpal[iii] tunnel (shown in the image below) is the anatomical passageway between the forearm and the hand. The tunnel is formed by the bones of the wrist (carpal bones) which are arranged in a semi-circular pattern and overlaid by the transverse carpel ligament. Passing through this tunnel are the flexor tendons of the fingers, various blood supplies and, importantly, the median nerve. The median nerve provides motor function to allow movement of the thumb as well as creating the sensation of touch in the skin of the thumb and the index, middle and ring fingers.

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(Source: Wikimedia Commons)

The other nerves to the hand, the radial and ulnar nerves, do not pass through the tunnel.  The median nerve relays physical sensations from the hand to the brain (touch), and it relays signals controlling movement from the brain to the hand.  CTS is caused by the nerve being compressed as it passes through the carpal tunnel into the hand.  Compression can occur if the tissues inside the tunnel become swollen or the tunnel narrows over time.

Causes

The cause of compression of the median nerve is often unknown, though risk factors are believed to include:

  • Family history of CTS;
  • Female gender;
  • Pregnancy;
  • Being overweight;
  • Wrist injuries, such as carpal fractures;
  • Health conditions such as diabetes, underactive thyroid and rheumatoid arthritis;
  • Abnormal wrist structures such as an unusually narrow carpal tunnel, or as a result of cysts, growths or swellings in the tendons or blood vessels that pass through the tunnel;
  • Menopause;
  • Playing a musical instrument;
  • Assembly packing;
  • Work that involves manual labour; and
  • Working with vibrating tools.

CTS is more common in women than in men, perhaps because the tunnel is smaller.  Approximately one in four people with CTS have a close relative who also has the condition, possibly due to hereditary smaller carpal tunnels.  CTS is common during pregnancy, possibly due to fluid retention leading to swelling of the contents of the tunnel, though many cases disappear after birth.  There is some evidence that hormones may play a role, as pregnancy and menopause may be risk factors. 

Activities that can be risk factors involve strenuous grip, repetitive wrist flexion and exposure to vibration.  The NHS notes that further research is required into the link between work-related hand use and CTS,[iv] and BUPA say that there is no strong evidence that working with a computer mouse or keyboard can cause CTS.[v] The NHS also comments that CTS is more common in patients who carry out strenuous activities than in those who spend extended periods typing.

Symptoms

Symptoms usually develop gradually, and in the early stages, tend to be worse during the night or early in the morning.  Symptoms may include:

  • Tingling in the hand and fingers;
  • Numbness in the hand and fingers;
  • Pain, sometimes a burning sensation, in the hand and fingers;
  • Pins and needles (paraesthesia);
  • Weakness of the thumb;
  • Dull ache in the hand, forearm or upper arm;
  • Dry skin, swelling or changes in the skin colour of the hand;
  • Decrease in sensitivity to touch (hypoaesthesia);
  • Weakness and muscle mass loss (atrophy) of muscles at the base of the thumb;
  • Weaker grip;
  • Dropping objects;
  • Difficulty with intricate finger tasks such as fastening buttons or laces and typing; and
  • Carpal tunnel syndrome is caused because of raised pressure within the carpal tunnel which causes damage to the median nerve. When this occurs an individual can feel pain, tingling (paraesthesia) and/or numbness in the thumb and index, middle and ring fingers of the hand and sometimes extending down towards the base of the hand as shown in the shaded area in the image below.

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(Source: Wikimedia Commons)

Tingling, numbness and pain usually occur in the thumb, index finger, middle finger and half of the ring finger, as these are the areas innervated by the median nerve.  It is possible to have symptoms in one hand, but in many cases, both hands are eventually affected.

Symptoms are often worse after using the affected hand.  Repetitive motions of the hand or wrist, or keeping the arm or hand in the same position for a long period of time, can aggravate symptoms. 

Sufferers tend to wake with these symptoms at night. In many cases the symptoms are mild and intermittent and may resolve without treatment. In other cases the symptoms are more severe and constant and can lead to weakness and wasting of the muscles at the base of the thumb. The condition is then typically treated by use of splints and/or steroid injections or surgery.

Treatment

CTS can sometimes disappear without treatment, or with simple self-care measures.  These measures include:

  • Moving the hand or shaking the wrist;
  • Applying ice packs; and
  • Avoiding any activities that aggravate symptoms.

If CTS is caused by a wrist injury or rheumatoid arthritis, treating of this condition can improve CTS symptoms.

Mild or moderate symptoms may be treated with:

  • Wrist splints, which should keep the wrist in a neutral position, thus preventing flexion, which can aggravate symptoms. A splint may be suggested for use at night.
  • Corticosteroid[vi] injections, usually injected straight into the wrist. It has been reported that the average benefit time of injection was 27 weeks, with a range of 0 to 300 weeks[vii].

There is a lack of evidence to support the use of non-steroidal anti-inflammatories, such as ibuprofen, for treating CTS.  When a wrist splint does not reduce symptoms, corticosteroid injections may be suggested.

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(Source: Wikimedia Commons)

If non-surgical treatments fail to relieve symptoms, or if there is risk of permanent nerve damage, surgery may be performed. CTS surgery is carpal tunnel decompression or carpal tunnel release surgery, which involves cutting the flexor retinaculum to reduce pressure on the median nerve.  A local anaesthetic is used, though the patient remains awake during the procedure, and an overnight stay in hospital is not required.  Either open or keyhole surgery may be possible.  Surgery can relieve the symptoms immediately if there is no nerve damage, though if the nerve damage is severe, there may be no improvement, or improvement may take a long time.  Usually, surgery provides a complete and permanent cessation of symptoms, though there is a small risk of various complications, and a small scar might remain.  Carpal tunnel release surgery rates of 43 to 74 per 100,000 have been reported in the UK.[viii]

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(Source: Wikimedia Commons)

Duration, Prognosis and Effects on Work

Use of wrist splints can result in improvement of symptoms within about 4 weeks, though it can take up to 12 weeks.  In pregnant women, symptoms often disappear within 3 months of birth, though they may continue for over a year. 

Mild symptoms in those aged under 30 can often disappear without treatment within 6 months.  It has been reported that patients who do not have surgery have a median duration of symptoms of between 6 and 9 months, though 22% had symptoms for longer[ix].

Full recovery from surgery can take about 8 weeks, and it may take several months for the strength in the hand and wrist to return to normal.  The hand is bandaged and often in a sling for the first few days, and many patients can drive and do activities that involve light lifting and gripping soon after surgery.  It is recommended that the hand be used for more demanding activities only when it has recovered.  Recovery from open surgery usually takes slightly longer than recovery from keyhole surgery.  Surgery usually requires a few weeks of absence from work.  It has been reported that in the US, median lost work time from work-related CTS is 27 days, which is the second longest for any work-related disorder (fractures is the longest).[x]

One study found that patients who had surgery were approximately 6 times more likely to have resolution of their symptoms than those who did not.[xi]  The same study reported that patients who had surgery 3 or more years after their initial diagnosis were less than half as likely to have symptom resolution than patients who had surgery within 3 years of diagnosis.  Symptom reduction is expected in 70-90% of patients who undergo surgery.[xii]

The Nuffield Orthopaedic Centre NHS Trust has published a leaflet providing patient information on CTS.[xiii]  Its advice includes:

  • Stiches will be removed 10-14 days after surgery, usually when the patients returned to the outpatient clinic for hand therapy;
  • Once the stitches have been removed, the more the hand is used for day-to-day activities, the quicker it will recover;
  • Slight discomfort when you use the hand is not harmful, but persistent pain may mean you have used it too vigorously;
  • The only action to be avoided for the first 4 weeks is excessive weight-bearing through the heel of the hand, e.g. pushing up from a chair, and heavy gripping tasks;
  • The fingers should be straightened out and then a first made every few hours;
  • The patient should not drive until the stitches are removed and they are certain they have enough strength and control to drive safely; and
  • The patient can return to work as soon as their hand can cope with it.  Depending on the job, return to work may be possible once the stitches are removed.  Expect up to 4 weeks off work if the job involves heavy duties, e.g. manual work.

The following effects of CTS on work status have been reported:

  • Patients presenting with CTS were more likely to continue working if they had modifications to their jobs, worked for employers with fewer than 250 employees, and held jobs not characterised by the frequent use of force;[xiv]
  • Predictors of successful work role functioning 6 months after surgery are baseline work role functioning, improved self-efficacy and a supportive organisation;[xv]
  • 6 months following surgery, 19% were out of work; 12 months following surgery, 22% were out of work.  Factors associated with work absence at 6 months included preoperative functional status, change in self-efficacy between preoperative assessment and 2 months, lower income, workers’ compensation, representation by an attorney, work exposure to force and repetition, higher psychological job demands and lower control, lower social support by co-workers, lower job security and more supportive occupational policies and practices.  Factors associated with work absence at 12 months included preoperative functional status, lower self-efficacy at 2 months, workers’ compensation, and less supportive organisational policies and practices;[xvi]
  • Professional exposure to repetitive movements and heavy manual handling activity were associated with a longer return-to-work period.  The overall duration of work incapacity was 34 days;[xvii]
  • Diagnosis of CTS is a predictor for longer duration of disability among workers’ compensation claims;[xviii]
  • 98% of workers returned to work by 3 months following surgery, and the time taken to return ranged from 1-88 days.  Surgeons’ recommendations, physical work and lack of self-related health were the most significant factors for delayed return to work.  Workers will return to work in less than 3 weeks if recommended by the surgeons;[xix]
  • 45% of patients changed jobs or were absent from work (aside from post-operative recovery) during a 30-month follow up.  Predictors or work absence at 18 months included worse functional status at enrolment and at 6 months follow up, involvement of an attorney at the time of enrolment and work absence at 6 months;[xx] and
  • Predictors of chronic work disability (at least 180 days of work disability compensation in the year after claim submission) included demographic variables, symptom severity, functional limitation, lack of job accommodation, job physical demands, job psychosocial condition and work psychosocial characteristics.[xxi]

Medical Causation in CTS Claims

The immediate cause of the median nerve injury is generally believed to be raised pressure in the carpal tunnel which obstructs the circulation to the nerve.[xxii] Why is the pressure raised? It is often the case that there is no clear cause of the CTS – it is frequently idiopathic.[xxiii] Nevertheless, CTS is also strongly associated with a number of constitutional factors, such as genetic pre-disposition, obesity, age, hormones, gout, hypothyroidism, rheumatoid arthritis, oedema (excess build-up of bodily fluid), pregnancy and diabetes.[xxiv] Further there are a number of associations with mechanical injuries, such as sprains and fractures. However, CTS has also been linked to occupation, including activities requiring high levels of force, repetitive actions, posture and vibration.[xxv] Indeed, it is widely accepted that forced and repetitive movements of the wrist can result in CTS.[xxvi] This article is concerned with vibration and seeks to examine the scientific link between vibration exposure and CTS.

CTS and Work

The IIAC is an independent statutory body that advises the Secretary of State for Work and Pensions in Great Britain and the Department for Social Development in Northern Ireland on matters relating to the Industrial Injuries Scheme. The Scheme, Industrial Injuries Disablement Benefit (IIDB), provides compensation that can be paid to an employed earner because of the effects of an industrial accident or prescribed disease.

In order for a disease to become a prescribed disease the Social Security Contributions and Benefits Act 1992 states that the Secretary of State must be satisfied that the disease:

  • Ought to be treated, having regard to its causes and incidence and any other relevant considerations, as a risk of the occupation and not as a risk common to all persons; and
  • Is such that, in the absence of special circumstances, the attribution of particular cases to the nature of the employment can be established or presumed with reasonable certainty.

So, a disease may only be prescribed if there is a recognised risk to workers in an occupation, and the link between disease and occupation can be established or reasonably presumed in individual cases.

The Council applies a doubling of the risk test to determine whether a disease can be attributed to occupation on the balance of probabilities.

In its 2006 Command Paper, Work-related Upper Limb Disorder (Cm 6868) the IIAC found that carpal tunnel syndrome should be a prescribed disease but only in the following circumstances:

  • Where the individual carries out repeated palmar flexion and dorsiflexion of the wrist for at least 20 hours per week, for at least 12 months in aggregate in the 24 months prior to onset of symptoms;
  • Where the individual uses vibratory tools when symptoms first onset.

Appendix 2 to the IIAC’s report provides a figure demonstrating palmar flexion and dorsiflexion of the wrist, as set out below. The main text of the report confirms that repeated in this context means once or more in every 30 seconds and the individual should present with symptoms either during or within 6 months of leaving employment.

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Many claims for carpal tunnel syndrome can be challenged on the basis of the specific criteria laid down by the IIAC for development of the condition related to occupation. The assumption that carpal tunnel syndrome is caused by exposure to vibration is controversial and can also be challenged in certain circumstances.

CTS and Vibration

The issue of whether CTS could be caused by exposure to excessive levels of vibration first began to be considered in the 1980s. For instance, Ahlborg et al[xxvii] in 1982 and Wieslander et al[xxviii] in 1989 sought to explore the correlation between the use of vibrating tools and the development of CTS. Wieslander et al concluded, ‘There is an association between exposure to handheld vibrating tools and the occurrence of CTS’ and, further, ‘The observed dose response relations and the demonstrated additive effects of different risk factors indicate a cause-effect relation between CTS and exposures to handheld vibrating tools’.

CTS arising from the use of handheld vibrating tools first became a prescribed disease for the purposes of Industrial Injuries Disablement Benefit on 19 April 1993 following publication of a report on work related upper limb disorders by the Industrial Injuries Advisory Council in May 1992.[xxix] This report found an association between the use of handheld vibrating tools and CTS. This conclusion was largely based on a literature review by Palmer et al which found a doubling of the risk of CTS arising from exposure to excessive vibration.[xxx]

The Strength of Association: Cause or Trigger?

Palmer et al  conducted an updated review of the medical literature on the occupational risk factors in 2007, which concluded that there was ‘reasonable evidence that regular and prolonged use of hand-held vibratory tools increases the risk of CTS >2-fold’,[xxxi] confirming the earlier statistical evidence provided to the Industrial Injuries Advisory Council. The evidence gathered on lesser durations and degrees of exposure was reported as limited but did not exclude the possibility of a doubling of the risk of developing CTS. Nevertheless, it was clear that the real association between vibration and CTS concerned regular and prolonged exposure.

This review was supported by Barcenilla et al which found exposure to repetition, force, vibration and poor wrist postures led to an increased risk of developing CTS of between two and five-fold.[xxxii]  The review was additionally support by Burke et al’s study of miners. They undertook a review of claimants seeking compensation for exposure to vibration in the mining industry.[xxxiii] 26,842 individuals were assessed and 15% of the subjects were assessed as having HAVS and CTS. Interestingly, only 105 of the subjects (0.4%) were diagnosed with CTS alone; this is discussed further below.

By comparison, a 2009 review by Lozano-Calderón et al concluded that, ‘the etiology of CTS is largely structural, genetic, and biological with environmental and occupational factors such as repetitive hand use playing a minor and more debatable role’.[xxxiv] The review by Lozano-Calderón et al covered a broader range of factors than that of Palmer and Barcenilla and sought to assess the strength of association with non-occupational factors, such as obesity, diabetes, age and gender, as well.

The Lozano-Calderón review also based its conclusion on the wider Bradford Hill criteria, which assesses the strength of association based on various factors, namely plausibility, experiment/extent of research, strength of association, biological gradient, consistency, specificity, temporality, analogy and coherence. Based on the extent to which the risk factor fulfilled these criteria in each of the medical articles reviewed by the authors, that factor was assigned a point score; the higher the point score the greater the association with CTS. In the case of vibration, the average score was 6.33 points (range of 5 to 8 points) and the conclusion was that vibration was found to be, ‘a plausible but debatable risk factor’. The results of the authors’ investigation are listed in the table below:

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From the medical research carried out and recorded to date it appears undeniable that there is a positive correlation of results between prolonged exposure to excessive levels of vibration and the development on CTS. But is this sufficient for a claimant to establish causation? In CTS cases the traditional ‘but for’ test of causation applies – a court must be satisfied on the balance of probabilities that vibration caused the CTS; it must be more likely than not that vibration caused CTS. Does the evidence establish this, particularly when it is placed in context of other causal risk factors.

Putting Things in Context

The key message from the Lozano-Calderón review is that, even though exposure to vibration can increase the risk of developing CTS, non-occupational factors should be eliminated first since they may be more strongly associated with CTS; vibration might be a cause but it may be a subsidiary one compared to other risk factors.

Across the full range of risk factors, non-occupational causes presented a higher risk of causing CTS than exposure to vibration. This was also supported in a paper by Burt et al in 2011 which concluded that individuals with a BMI equal to or greater than 30 who carried out 15 exertions per minute had an increased OR of 3.35;[xxxv] that is to say those with a BMI equal to or greater than 30 were 3.35 times more likely to develop CTS compared to those with a lower BMI.

The consequence of these findings is that in any case alleging the development of CTS in consequence of exposure to vibration, the presence of any other of the above risk factors is arguably more likely to be the cause of the CTS. This may be sufficient to defeat a claim on the basis of causation; the court could not be satisfied that it was more likely than not that vibration was responsible for the CTS. Instead, the other non-occupational factor would be the more likely cause. Thus defendant practitioners should rigorously challenge causation in those cases where other risks factors are present or where the exposure was not regular or prolonged, while at the same time considering whether there is the risk of any aggravation/exacerbation claim arising out of the exposure.

CTS Alone?

As we saw above, Burke et al’s 2005 review of claimants seeking compensation for exposure to vibration in the mining industry found that only 105 of the subjects (0.4%) were diagnosed with CTS alone; 99.6% of the other sufferers had also developed hand arm vibration syndrome (HAVS) – a condition proven to be the consequence of exposure to vibration. This suggests that in terms of medical causation, it is unusual for a Claimant to develop vibration-induced CTS but not to demonstrate symptoms of HAVS. This seems logical – if HAVS is accepted as medically associated with vibration but CTS is debatably so associated, it would be curious for vibration to induce CTS without having induced HAVS. This point was addressed in the unreported case of Ward v Rotherham Metropolitan Borough Council.[xxxvi] In that case the claimant sought compensation for bilateral CTS arising from his use of vibrating tools between 1994 and 2009 (15 years). Breach of duty had been conceded by the defendant but causation was disputed on the basis that the claimant was obese. The court was required to determine whether the cause of the claimant’s CTS was his exposure to vibration (which had been admitted) or his obesity.

The defendant’s medical expert explained that he could not see how vibration could be a cause of CTS at all and that he was awaiting scientific evidence to establish the pathology.  Further, the defendant’s expert advised that he could not accept that vibration had caused the claimant’s injury as he exhibited no symptoms of HAVS, ‘I don’t believe it is possible for certain nerves to escape the problem and for the problem only to affect the median nerve at the level of the carpal tunnel’.

In this regard the expert was explaining that, in his view, if the level of vibration had been sufficiently severe and prolonged as to cause damage to the median nerve (which is deeper in the wrist) then it should reasonably be expected to have also damaged the peripheral nerves associated with the development of HAVS. The court ultimately preferred the evidence of the defendant’s expert and found that vibration had not been the cause of the claimant’s CTS.

Conclusions

While most cases of CTS arise from non-occupational causes, the current medical literature supports a causal association between forced and repetitive movement of the wrist and CTS. There is also a positive correlation between the use of handheld vibrating tools and the development of CTS in so far as the general trend of results shows that individuals heavily exposed to the use of handheld vibrating tools are also more likely to develop CTS. However, it is also clear that there is no established causative link between vibration exposure and CTS and no clearly defined dose-response relationship. Can it be said that CTS is associated with relatively light or modest vibration exposure? As a result, a general correlation of results should be taken at best to indicate a possible – and not a probable – link between vibration and CTS. Non-occupational risk factors, such as obesity, diabetes and genetic factors (to name a few), should be fully discounted before any occupational factors like vibration are considered. Where other risk factors are present – which are more strongly associated with CTS and likely to outweigh the impact of any vibration – causation should be challenged. Moreover, in cases of apparent vibration induced CTS it may well be that the physical work itself is resulting in CTS, rather than vibration. In addition, it remains unclear whether vibration induced CTS can arise in the absence of HAVS.

TEMPLATE SCHEDULE OF INVESTIGATIONS IN A WRULD CLAIM

Detail any preliminary enquiries made with the insured, setting out what information the insured has provided to date. Then concisely summarise what else needs to be investigated / clarified by identifying the main issues in dispute which require further investigation. For example:  

Lay Evidence

The Claimant

  • What was / is the claimant’s ( C ) job role and periods of employments?
  • What site(s), departments, lines, operations & processes does / did the C work at with relevant dates for the same?
  • What was C’s days and hours of work, including any regular overtime?
  • What were his / her rest breaks-formal and informal-including frequency and duration of the same?
  • Obtain a broad timeline of what happened. When did C first:
    • Start the work complained of?
    • Raise any problems concerns regarding his work?
    • Develop symptoms?
    • Go absent from work?

[Further details on complaints and absences etc. requested below]

  • Did C have any particular requirements at material time-e.g. new or expectant mother, disability and / or health problems, migrant worker with poor communication skills in English? Any physical or learning disability?

Manual Handling Operations

  • Is it accepted that the work carried out by C involved manual handling?
  • Is it accepted that this was manual handling work to which the Manual Handling Operations Regulations 1992 as amended (MHOR) would apply?

[Note: The MHOR apply to ‘manual handling operations’ which include transporting or supporting of a load (such as lifting, putting down, pushing, pulling, carrying or moving) by hand or by bodily force. A ‘load’ includes any discrete moveable object including any person or animal. They do not apply where the load is a tool used for its intended purpose.

Under MHOR there is a hierarchy of duties requiring employers to do the following:

  1. Avoid the need for hazardous manual handling operations, so far as is reasonably practicable;
  2. Assess the risk of injury from any hazardous manual handling operations that can’t be avoided; and
  3. Reduce the risk of injury from hazardous manual handling operations, so far as is reasonably practicable].

Avoiding the Manual Handling Operations, As Far As Reasonably Practicable

  • Have the insured considered avoidance of the manual handling operations, such as through automation or use of mechanical handling aids such as a conveyor, pallet truck, electric hoist, lift truck etc.?
  • If so when and how was this considered and by whom?
  • What was the conclusion reached and why?
  • Why was it not reasonably practicable to avoid the operations?

Risk Assessment

  • Have the insured carried out risk assessments regarding the operations / process and in particular the manual handling operations?
  • If so when and how were these risk assessments carried out and by whom?
  • Where the risk assessments suitable and sufficient? Did they consider the factors listed in Schedule 1 to the Manual Handling Operations Regulations (i.e. the task itself, the loads, the work environment, individual capability and physical suitability of the employee, and other factors such as whether movement or posture is hindered by personal  protective equipment or clothing).
  • Have the insured followed the manual handling risk assessment flow chart in the HSE Guidance to the MOHR? Have the insured used the HSE’s risk assessment filter for manual handling and/or the risk assessment filter for upper limb disorders in the workplace. Have the insured incorporated the Manual Handling Assessment Charts (MAC tool) and/or the Risk Assessment for Pushing and Pulling (RAPP tool) and/or Assessment of Repetitive Tasks (ART tool) as part of their assessments? Obtain full details.
  • If the risk assessments were not suitable explore reasons / why not?
  • How often were risk assessments reviewed and why?
  • Details of insured’s general Health and Safety structure and policies and procedures.

Control Measures

  • What control measures were identified by the risk assessments to reduce the risk of injury?
  • Have these been implemented? If not, why not?
  • If they have been implemented when were they implemented, how and by whom?
  • Obtain details of the existing control measures currently in place and throughout the C’s employment and reasons for any changes such as availability of mechanical lifting aids, any system of rotation (e.g. whether written or verbal, how it is implemented, the frequency/duration of tasks in the work schedule, and the extent of opportunity for rest/recovery in addition to formal rest breaks) or training programme for manual handling and/or WRULDs.

The Work

[Note: Some of these questions may overlap with the above.]

  • Please take a video of the work carried out by C-ideally of someone the same height, weight and gender. Obtain relevant measurements and photographs.
  • Obtain full details of the nature and extent of the manual handling and/or repetitive work as follows:

The Load / The Task

  • What are the loads?
  • The weight of the loads?
  • The size and shape of the loads?
  • Are the loads an awkward shape or bulky making them difficult to handle?
  • Are the contents of the load able to move or move unpredictably (like animals) and make it difficult to handle?
  • Are the loads easy to grip? Do they have handles or handholds? Do they have loose parts enabling comfortable grip?
  • Hot or cold or sharp?
  • How many people handle the load? (See also below)
  • Does the task require and large vertical movements?
  • Does the task require unusual capability-above average strength or agility?
  • Is the task complex?
  • Does the task require special information or training for its safe performance?

For Lifting Operations

  • What height is the load lifted from and to (e.g. from knuckle to elbow height)?
  • What is the proximity of the load to the body (e.g. held close to the body or with arms outstretched)?
  • Is the handler’s body position stable?
  • Is any lifting carried out whilst seated?
  • What is the hand distance from the lower back-see image below[xxxvii]?

13.png

(Source: HSE)

  • What are the hand positions during course of lift-see image below? Obtain details.

14.png

(Source: HSE)

  • Is there are twisting of the torso or sideways bending-see image below? Obtain details;

15.png

(Source: HSE)

For Carrying Operations

  • What height is the load carried at / where are the hands located (e.g. hands held at elbow height)?
  • What is the proximity of the load to the body (e.g. held close to the body or with arms outstretched)?
  • What is the distance over which the load is carried?
  • Is the handler able to walk normally?
  • Does the load obstruct the handler’s view?
  • Is the load supported on the shoulder?
  • Is there any twisting of the torso during carrying?
  • What is the horizontal distance between the hands and the lower back? See image below?

16.png

(Source: HSE)

  • What is the carrying position adopted? Are the load and hands symmetrical in front of the body? Or are they asymmetrical? Or is there one handed carrying to the side? See image below.

17.png

(Source: HSE)

  • Are there any obstacles on route? Is there any need to go up a steep slope or steps or closed doors or around / over any tripping hazards or up ladders etc.? Obtain full details.

For Team Handling Operations

  • What is the horizontal distance between each person’s hands and lower back? See image below.

18.png

(Source: HSE)

  • What is the position of the hands during the course of the lift? See image below.

19.png

(Source: HSE)

  • What is the distance over which the load is carried?
  • Is there any twisting of the torso during lifting / carrying?
  • Are operatives able to communicate effectively to handle the load?

For Pushing/Pulling Operations

  • How is the force applied to the load (e.g. with the hands or shoulder)?
  • Is the torso largely upright or inclined and the level of the incline?
  • Is the torso bent or twisted and the level of this?
  • If the hands are used where are the hands held to support the load (e.g. between hip and shoulder level)?
  • What distance is the load pushed or pulled?
  • Are there any obstacles on route? Is there any need to go up a steep slope or steps or closed doors or around / over any tripping hazards or up ladders etc.? Obtain full details.
  • How is the load moved e.g. rolled, churned, dragged/slid?
  • What equipment is used to carry out the pushing/pulling? Is it suitable and well maintained?
  • How do the hands grip the load? See table below:

20.png

(Source: HSE)

Handling Aids and Equipment

  • Are any handling aids used? What are these and when implemented?
  • Are these aids correct for the task?
  • Are the wheels on the aid suited to the floor surface?
  • Do the wheels run freely?
  • Are there any brakes? Do they work?
  • Are the aids properly maintained and serviced?
  • Any reported problems with aids?
  • Are the aids freely available or difficulties in obtaining these?

Signs and Symptoms of ULDs

  • Are there any medically diagnosed cases of ULDs from the work?
  • Are there any complaints of aches and pains?
  • Are there any Improvised changes to work equipment or tools?
  • Are workers reluctant to do the job complained of?
  • Have workers requested to be redeployed or taken off the job complained of?
  • Is there any evidence of workers carrying out the job complained of wearing splits or bandages?
  • Is there any evidence of employees carrying out the job complained of using painkillers or other pain relief medication?

Repetition

With reference to each individual task performed:

  • Are arm movements intermittent, regular or almost continuous?
  • Is a similar motion pattern for the arm and hand completed 10 times per minute or less, 11-20 times per minute or more than 20 times per minute?

Force

With reference to each individual task performed:

  • What level of force is required to carry out the task – see table below

21.png

(Source: HSE)

  • What percentage of time is the level of force identified required to be used to carry out the task? – see table below.

 22.png

(Source: HSE)

Posture

With reference to each individual task performed:

  • Is the head or neck bent or twisted and what percentage of the time is the head bent or twisted – see image below?

23.png

(Source: HSE)

  • Is there any grasping/gripping for more than 2 hours total per shift?
  • Is the back twisted or bent 20 degrees or more and how often is it like this – see image below?

24.png

(Source: HSE)

  • Is either elbow raised around chest height and unsupported and how often is it like this – see image below?

25.png

(Source: HSE)

  • Is either wrist bent or deviated and how often is it held like this – see image below?

26.png

(Source: HSE)

  • How do the fingers or hands hold objects – see image below?

27.png

(Source: HSE)

Duration and Frequency

  • How frequently are breaks taken from manual handling and/or repetitive work?
  • Are there natural breaks in the work and the extent of the natural breaks (e.g. 10 seconds every few minutes)?
  • The frequency of the handling and/or repetitive work carried out per minute / hour / over the course of a working day;
  • The duration of each individual task;
  • The cumulative duration of manual handling and/or repetitive work in a working day;
  • An estimate of manual handling work and/or repetitive work as a proportion of a working day;
  • How many days per week the manual handling work and/or repetitive work is carried out-daily and regular task / weekly and irregular etc?
  • Details of any formal job rotation between different tasks and a description of what the other tasks in the work schedule involved (including the extent of any manual handling and/or repetitive work) and the frequency/duration of each task in the rotation schedule;
  • Details of any natural variation of duties within the work and the frequency/duration of the variation;
  • Is the work rate imposed by a process and / or targets?
  • Is the work difficult to keep up with?
  • Is there sufficient rest or recovery time between handling and/or repetitive work?
  • Any seasonal variations in work-full details;

Environment and Other Factors

  • Can manual handling and/or repetitive work be carried out without hindrance? Are there any space restrictions? Do these cause restricted postures to be adopted?
  • What is the floor surface? Is it dry and clean and in good condition? Is it worn or uneven? Is it wet or slippery or unstable? Is it flat or sloping? Are there variations in floor levels, steps, closed doors or ladders to negotiate?
  • Are there any extremes of temperature (hot or cold)?
  • Do gusts of wind or strong air movements hinder handling and/or repetitive work?
  • Is handling and/or repetitive work carried out in extreme lighting conditions (dark, bright or poor contrast)?
  • Any tools or PPE used and any whether this has any impact on the work;
  • Are any tools used in either hand to strike an object and the frequency of this?
  • Is either hand used as a tool to strike something and the frequency of this?
  • Does the work involve any compression of the skin?
  • Does the work involve exposure to vibration?
  • Does the work involve any precise or fine movements of the hands or fingers?

Training

  • Please detail the training provided to the C in relation to the work generally and the tasks carried out in department;
  • Details of any induction and/or refresher training provided to the claimant in relation to the risks of manual handling and/or repetitive work. What exactly did the training cover, for example:
    • Weight of loads handled;
    • Presence of risk factors;
    • How injuries can occur;
    • How to avoid injuries;
    • How to carry out safe manual handling and/or repetitive work;
    • How to use aids safely and correctly; and
    • When and how to report any accidents and health problems and seek medical advice & assistance?
  • When, how and who carried out the manual handling and/or repetitive work training and what qualifications/experience did they have?

Complaints / Occupational Health

  • Obtain details of the insured’s system relation to injury complaints;
  • Identify whether C made any complaints about the nature of the work and/or his injury to managers/supervisors/ other employees;
  • If complaints made then when and to whom and nature/gist of the same?
  • How were C’s complaints were dealt with-when and by whom-and what was the outcome? Did C carrying on with work complained of?
  • Details of the insured’s occupational health arrangements / policy;
  • Was C referred to Occupational Health-if so how, when and by whom?
  • What was done following the referral including the occupational health advisor’s recommendations and whether these were followed);
  • Were there any previous complaints about work or accidents / injuries from or others? If so when, from whom, to whom, nature / gist and what happened as a result / what action taken?

Absences and Returns to Work

  • Dates of absences from work and reasons?
  • Any assessment of capability for work on return?
  • Graduated return to work / any restrictions imposed / different work carried out?
  • Did C return to same work-if so when?
  • Were there any subsequent complaints by C after the injury / absence? If so when and to whom and nature / gist of the same? How was this dealt with and what was the outcome?
  • Identify in retrospect whether anything could have been done differently.
  • Was C’s employment terminated? If so when and for what reason(s)?
  • Was C placed on different work which effected income? Obtain full details.

Documents

This Checklist is intended only to be a guide and it is not exhaustive.

NB: IN CASES WHERE SUCH DOCUMENTS ARE NOT AVAILABLE IT IS VITAL TO CLARIFY WHETHER (I) THEY NEVER EXISTED, OR (II) IF THEY DID WHAT BECAME OF THEM AND WHEN?

The Injury

  1. Accident Book entry for the claimant’s injury and any other relevant incidents.
  2. Form F2508/ F2508A (submitted to the Health & Safety Executive). Any other documents completed for the purposes of RIDDOR 2013.
  3. Any HSE investigations or correspondence in relation to the claim, any other similar incidents or the system of work in general.
  4. Any other investigation reports or forms, including any statements taken or memos sent.
  5. First Aid/Treatment Book entry.
  6. Sick Notes submitted by the Claimant.
  7. Documents relating to any other similar claims or Accident Book entries etc.

Manual Handling/ Repetitive Work

  1. In relation to the period about which the claimant is complaining, documentation to show:
    1. The claimant’s Day Work Sheets (including details of basic hours worked and any overtime);
    2. A breakdown of the claimant’s daily activities and frequency rate of manual Handling and/or repetitive work (e.g. diaries, calendars, rosters);
    3. The claimant’s performance targets and actual achievement/production levels;
    4. Average speed of the process (e.g. in terms of units per minute, per hour or per shift). If excessive keyboard work is alleged documents to show the keystroke rate;
    5. If the Claimant was above or below average, documents to show this (e.g. statistics or a comparator employee’s Day Work Sheets etc.);
    6. The weight, size and shape of the loads;
    7. Duration and frequency of manual handling and/or repetitive work;
    8. The relevant software that was used and the workstation equipment.

Risk Assessments and Health & Safety Records

  1. Health & Safety Committee Meeting Minutes which refer in any way to the subject matter of this claim.
  2. The Company’s Health & Safety Policy.
  3. Any other relevant internal health and safety documents, including memos and e-mails, relating to manual handling and/or repetitive work.
  4. Maintenance, inspection and/or repair records for all relevant equipment, plant or tools used by the Claimant.
  5. Risk Assessments — for the period of the Claimant’s employment and also one year before and to date, in relation to:
    1. Manual Handling Operations Regulations;
    2. Management of Health & Safety at Work Regulations;
    3. Provision and Use of Work Equipment Regulations;
    4. Workplace (Health, Safety and Welfare) Regulations;
    5. Personal Protective Equipment regulations;
    6. Health and Safety (Display Screen Equipment) Regulations;
    7. Any re-assessments following changes (e.g. to the work station, to the system of work or following any accidents or health surveillance);
    8. Any other relevant risk assessments undertaken.
  6. Documents showing any other sources of information obtained, such as:
    1. Any independent health & safety reports commissioned;
    2. Time-in-motion studies; work surveys; ergonomic assessments;
    3. Documents obtained from HSE, trade associations, health & safety industry journals.

Control Measures

  1. Documents showing what steps have been taken, if any, to reduce, eliminate or avoid risk of injury. In particular:
    1. Rotation;
    2. Rest Breaks;
    3. Tools and equipment;
    4. PPE;
    5. Ergonomic layout of the workstation/work area;
    6. Provision of training where appropriate;
    7. Complaints systems;
    8. Referrals to occupational health;
    9. Any documents showing systems of review, maintenance or testing regarding the above;
    10. Any documents which explore the possibility of the above or other control measures.
  2. Documents showing what mechanical assistance was available to the claimant, in particular:
    1. Manufacturers’ specifications (e.g. catalogues, marketing information);
    2. Any manuals in respect of the use of the equipment;
    3. Maintenance and repair records.

Training and Enforcement

  1. Health & Safety Handbook/Manual — preferably the copy signed and dated by claimant to acknowledge receipt.
  2. Documents showing all training, instructions and warnings (e.g. training certificates, course notes, course registers, internal memos, publicly displayed warning notices, handbooks/booklets, notes of guidance and any other literature etc.) given to the Claimant in respect of relevant matters such as:
    1. Safe manual handling techniques;
    2. The hazards of repetitive work;
    3. Other risk control measures;
    4. Recognition of symptoms;
    5. The need to report symptoms and seek medical assistance;
    6. How to perform workstation assessments;
    7. Understanding the correct ergonomic arrangement of the workstation and how to minimise risks by adopting the correct working posture.
  3. The Claimant’s Training Records for all aspects of the work and, in particular, for manual handling and/or WRULDs.
  4. Information provided to the claimant regarding the weight of the loads.
  5. Documents relating to enforcement procedures, including warnings given and disciplinary procedures taken against employees (particularly the claimant) for failure to follow manual handling procedures and health and safety policies generally.

Health Surveillance

  1. Documents detailing any system of health surveillance (e.g. undertaken by who, when, how often and in respect of what). Complaints or comments and action taken
  2. Documents relating to any written or oral complaints or comments by the claimant or any other employees about symptoms or the system(s) of work.
  3. Documentation detailing the Company’s response to any such complaints or comments and what action was taken, if any.
  4. All correspondence passing between the Company and the Health & Safety Executive regarding this incident or any other similar matters.

Wages, Benefits and Absences

  1. Details of the claimant’s net weekly pre-absence earnings for a period of 13 weeks.
  2. Details of all payments made to the claimant during any periods of absence (from work due to the alleged injury-SSP/CSP/Holiday and bonus payments /PHI if PHI scheme fully funded by insured).
  3. The Claimant’s Absence Record (including all absences due to sickness, holidays, training etc.).
  4. If the claimant was moved to alternative work:
    1. Details of the pay in the new job compared with the old job (including differences in shift allowances and bonuses).
  5. If the Claimant’s employment was terminated:
    1. The date on which the employment ceased;
    2. All letters and documentation relating to the termination.
  6. If the Claimant was made redundant:
    1. All documents relating to the redundancy, including the selection procedure, details of payments made etc.
  7. Pension details, if applicable:
    1. Pension handbook;
    2. Pension statements;
    3. Copy correspondence confirming details of how the pension would be affected (if the Claimant’s employment was terminated or made redundant).

Confidential Records

[Forms of authority from C required]

  1. Works’ Medical Records/Occupational Health Records.
  2. Full Personnel File (including Contract of Employment and job description).

 

[i] http://www.nhs.uk/Conditions/Carpal-tunnel-syndrome/Pages/Whatisit.aspx

[ii] Gelfman, R. et al. Long-term trends in carpal tunnel syndrome. Neurology 72, 33–41 (2009).

[iii] The word carpal originates from the Greek ‘karpos’ meaning wrist.

[iv] http://www.nhs.uk/Conditions/Carpal-tunnel-syndrome/Pages/Causes.aspx

[v] http://www.bupa.co.uk/health-information/directory/c/carpal-tunnel

[vi] Corticosteroids, or steroids, are anti-inflammatory medicines that are a synthetic version of human hormones.  They are used in a wide range of applications to reduce inflammation, though there are side effects associated with prolonged use of high doses, particularly when administered in tablet form.

[vii] Kulick, M. I., Gordillo, G., Javidi, T., Kilgore, E. S. & Newmeyer, W. L. Long-term analysis of patients having surgical treatment for carpal tunnel syndrome. Journal of Hand Surgery 11, 59–66 (1986).

[viii] Jerosch-Herold, C., Leite, J. C. & Song, F. A systematic review of outcomes assessed in randomized controlled trials of surgical interventions for carpal tunnel syndrome using the International Classification of Functioning, Disability and Health (ICF) as a reference tool. BMC Musculoskeletal Disorders 7, 96 (2006).

[ix] DeStefano, F., Nordstrom, D. L. & Vierkant, R. A. Long-term symptom outcomes of carpal tunnel syndrome and its treatment. Journal of Hand Surgery 22, 200–210 (1997).

[x]Dale, A. M. et al. Prevalence and incidence of carpal tunnel syndrome in US working populations: pooled analysis of six prospective studies. Scand J Work Environ Health 39, 495–505 (2013).

[xi] See DeStefano et al., above

[xii] Gimeno, D., Amick, B. C., Habeck, R. V., Ossmann, J. & Katz, J. N. The role of job strain on return to work after carpal tunnel surgery. Occup Environ Med 62, 778–785 (2005).

[xiii] Nuffield Orthopaedic Centre NHS Trust, Oxford Upper Limb Unit, Hand Physiotherapy Department, Carpal Tunnel Syndrome, 2007

[xiv] Faucett, J., Blanc, P. D. & Yelin, E. The Impact of Carpal Tunnel Syndrome on Work Status: Implications of Job Characteristics for Staying on the Job. J Occup Rehabil 10, 55–69 (2000).

[xv] Amick, B. C. et al. Predictors of successful work role functioning after carpal tunnel release surgery. J. Occup. Environ. Med. 46, 490–500 (2004).

[xvi] Katz, J. N. et al. Determinants of work absence following surgery for carpal tunnel syndrome. Am. J. Ind. Med. 47, 120–130 (2005).

[xvii] Kesel, R. D., Donceel, P. & Smet, L. D. Factors influencing return to work after surgical treatment for carpal tunnel syndrome. Occup Med (Lond) 58, 187–190 (2008).

[xviii] Cheadle, A. et al. Factors influencing the duration of work-related disability: a population-based study of Washington State workers’ compensation. Am J Public Health 84, 190–196 (1994).

[xix] Ratzon, N., Schejter-Margalit, T. & Froom, P. Time to return to work and surgeons’ recommendations after carpal tunnel release. Occup Med (Lond) 56, 46–50 (2006).

[xx] Katz, J. N. et al. Prevalence and predictors of long-term work disability due to carpal tunnel syndrome. Am. J. Ind. Med. 33, 543–550 (1998).

[xxi]Turner, J. A. et al. Early predictors of chronic work disability associated with carpal tunnel syndrome: a longitudinal workers’ compensation cohort study. Am. J. Ind. Med. 50, 489–500 (2007).

[xxii] ‘Causes of CTS’ (Carpal-Tunnel.net) <http://www.carpal-tunnel.net/about-cts/epidemiology> accessed 26 June 2014

[xxiii] Ibid.

[xxiv] ‘Carpal Tunnel Syndrome – Causes (NHS Choices, 19 September 2012) <http://www.nhs.uk/Conditions/Carpal-tunnel-syndrome/Pages/Causes.aspx> accessed 24 June 2014.

[xxv] Ibid.

[xxvi] ‘Epidemiology: Occupation’ Carpal-Tunnel.net) <http://www.carpal-tunnel.net/about-cts/epidemiology> accessed 26 June 2014. See also, for example, van Rijn, ‘Association Between Work-Related Factors and the Carpal Tunnel Syndrome – A Systematic Review (2009) 35 Scand J Work Environ Health 19; Leclerc et al, ‘Upper-Limb Disorders in Repetitive Work’ (2001) 27 Scand J Work Environ Health 268; Evanoff et al, ‘Using Job-Title-Based Physical Exposures from O*NET in an Epidemiological Study of Carpal Tunnel Syndrome (2014) 56 Human Factors 166.

[xxvii] Ahlborg, Voog, Carpal tunnel syndrome I: vibration exposure and distal compression of the median nerve, Lakartidningen. 1982 Dec 29;79(52):4905-6.

[xxviii] Wieslander, Norbäck, C-J Göthe, Juhlin, Carpal tunnel syndrome (CTS) and exposure to vibration, repetitive wrist movements, and heavy manual work: a case-referent study (Accepted 18 January 1988).

[xxix] Work Related Upper Limb Disorders: Report by the Industrial Injuries Advisory Council in Accordance with Section 141 of the Social Security Act 1975 on the Question Whether Further Work Related Upper Limb Disorders Should be Prescribed (May 1992).

[xxx] See Industrial Injuries Advisory Council, ‘Work Related Upper Limb Disorders’ (Cm 1936, May 1992).

[xxxi] Palmer, Harris and Coggon, Carpal tunnel syndrome and its relation to occupation: a systematic literature review, Occupational Medicine 2007;57:57-66 .

[xxxii] Barcenilla, March, Chen and Sambrook, Carpal tunnel syndrome and its relationship to occupation: a meta analysis, Rheumatology 2012;51:250-261.

[xxxiii] Burke, Lawson, McGeoch, Miles and Proud, Carpal tunnel syndrome in association with hand-arm vibration syndrome: A review of Claimants seeking compensation in the mining industry, J Hand Surg Br. 2005 May;30(2):199-203

[xxxiv] Lozano-Calderón, Anthony, Ring, The Quality and Strength of Evidence for Etiology: Example of Carpal Tunnel Syndrome (April 2008).

[xxxv] Burt, Crombie, Jin, Wurzelbacher, Ramsey and Deddens, Workplace and individual risk factors for carpal tunnel syndrome, Occup Environ Med 2011;68:928-933 

[xxxvi] Sean Patrick Ward v Rotherham Metropolitan Borough Council (2013)

[xxxvii] All figures within this schedule reproduced from HSE Guidance Manual Handling Assessment Charts (the MAC tool), INDG383, (rev2), June 2014