UK Social Security and Child Support Commissioners' Decisions

[2007] UKSSCSC CI_3745_2006 (25 July 2007)

CI/3745/2006

DECISION OF THE SOCIAL SECURITY COMMISSIONER

1. My decision is that the tribunal's decision given on 29 June 2006 under registration No. U/42/140/2006/00280 was erroneous in point of law, as indicated at the oral hearing of this appeal in London on 30 May 2007. Under section 14(8) of the Social Security Act 1998, I set aside the tribunal's decision and remit the case for rehearing by a differently constituted tribunal in accordance with the following directions:
2. The tribunal should bear in mind that the sequence of developments of the claimant's various problems in this case are (all relating to her dominant left hand):

(a) Early 1996 - carpal tunnel syndrome (which has already been found to be Prescribed Disease A12 and is not the subject of this appeal);

(b) Later 1996 – tenosynovitis (claimed as Prescribed Disease A8 which is the subject of this appeal);

(c) 1997 - fractured wrist; and

(d) 1999 - amputation of little finger.

Both (c) and (d) had non-industrial causations. It will be necessary for the tribunal first to make findings as to whether the claimant is suffering from Prescribed Disease A8 – traumatic inflammation of the tendons of the hand or forearm, or of the associated tendon sheaths (PDA8), and if so the extent of her disablement.

3. The decision of a Tribunal of Commissioners in R(I) 3/91 gives clear guidance in circumstances such as the claimant's where several factors are to be considered:

"5. Paragraph (2) [of the Social Security (General Benefit) Regulations 1982 (the General Benefit Regulations)] requires that where there is some "other effective cause" of the disabilities in question those disabilities are to be taken into account in accordance with the provisions of the regulations. Paragraph (3) requires that where "the other effective cause" occurs before the industrial accident in question, the measure of disablement due to "the other effective cause" is, in effect, to be deducted from the total assessment. However, in our view, the assessment of disablement will take into account, not merely the disabilities arising out of the relevant accident, looked at in isolation, but also the interaction of that accident on "the other effective cause". Thus, if a claimant loses an eye in an industrial accident, but prior thereto he had, by reason of something happening unconnected with his work, already lost the other, the assessment would take into account not merely the disablement arising from the loss of the one eye in the accident in question, but the interaction of that loss on his previous condition i.e. his total blindness. Paragraph (4) is more complicated than paragraph (3); where "the other effective cause" occurs after the industrial accident in question, the assessment is limited to the disablement resulting from the industrial accident unless that assessment is 11% or more, in which case the assessment has to take account of any disablement resulting from the other effective cause "except to the extent to which [the claimant] would have been subject thereto if the relevant accident had not occurred" Thus, as in the case of paragraph (3), the assessment will take into account any interaction."

It follows that in the event that the claimant is accepted as suffering from PDA8, the assessment of disablement should then proceed on the basis that:

(a) under regulation 11(3) of the General Benefit Regulations the award for carpal tunnel syndrome (PDA12) should be offset against the percentage found in respect of the claimant's PDA8 as the PDA12 condition amounts to an injury or disease received or contracted before the development of PDA8 ; but

(b) under regulation 11(5) any additional disability arising out of the interaction between the two conditions should be added to the assessment for PDA8; and

(c) if the net assessment under (b) is 11% then under regulation 11(4) any interaction due to the fracture and/or the amputation should be added.

The new tribunal will also wish to consider the detailed submission of Dr Susan Reed on behalf of the Department for Work and Pensions (DWP) submitted by the Office of the Solicitor on 22 May 2007.

4. The claimant is a woman born on 16 March 1948 who is left handed. It is accepted that she had worked in an occupation which could give rise to an award. On 9 February 2006, she made a claim in respect of PDA8 – tenosynovitis. Following a medical examination the doctor recorded "she has numerous and confusing diagnoses. I could not see any convincing evidence of tenosynovitis – PDA8. She has a clinical diagnosis of carpal tunnel syndrome (PDA12) – mildly, intermittently, and not needful of surgery" (page 33). The claim in respect of PDA8 was rejected by the decision maker.
5. The claimant appealed, stating that she had first been diagnosed with tenosynovitis in February 1998 and that she did not think the examining doctor had seen the correct records. She wrote a further letter on 21 April 2006, (pages 41- 42) stating that she was diagnosed with carpal tunnel syndrome in 1996, tenosynovitis in 1998 and again in January 2006 when her wrists were injected. She had cortisone injections in her right shoulder "because of the rotator cuff [which] I believe used to be called tendonitis" and another injection was expected at the time of her letter. The decision was reconsidered but not revised and the appeal proceeded.
6. The tribunal was held on 20 June 2006, the claimant being present but not represented. She told the tribunal that she had been awarded 6% in respect of PDA12 from 15 April 1996 for life, there being no previous evidence in the papers as to this award. (At the time of the reconsideration in respect of PDA8 the DWP had suggested the claimant should make an application in respect of PDA12 (page 36)).
7. The tribunal was satisfied that the claimant had tenosynovitis at the date of claim, 8 February 2006, within the meaning of the Social Security (Prescribed Diseases) Regulations 1985 and assessed her disablement at 5% from 31 December 1996 to 31 December 2010, as a final assessment. To this figure of 5%, the tribunal added the 6% awarded in respect of PDA12, making 11%. It then took this figure of 11% as bringing the claim within regulation 11(4) of the General Benefit Regulations under which it considered it could award a further 3% for the loss of the claimant's little finger. This brought her up to the qualifying level for a pension of 14%.
8. With commendable frankness the tribunal concluded the decision notice with the observation that its problem was that it could not identify the legal basis whereby it could take such a step, but its analysis was identified in case, effectively, either the decision maker or the claimant wished to appeal.
9. With leave of the tribunal chairman the Secretary of State appealed, submitting that the tribunal had erred in its application of regulation 11(4) of the General Benefit Regulations, and had correctly identified that there was no legal basis for the manner in which it had assessed disablement in this case, as a result of which the decision was wrong in law. At that stage the Secretary of State took no issue with either the diagnosis of the claimant's condition as PDA8 (which in a typographical error, he referred to as PDA5 at that stage) nor with the assessed disablement at 5% but the tribunal had incorrectly applied regulation 11 of the General Benefit Regulations. The Secretary of State made further submissions as to how the matter should have been dealt with correctly, with which I do not need to deal in detail here.
10. The claimant confined her response to the problems which she experienced and that she had seen two occupational doctors and a consultant to whom she had been sent by the DWP. She felt the decision was fair and abided by the rules. She observed subsequently on the Secretary of State's more detailed submissions in progressing the appeal in front of the Commissioner:

"The tribunal are clearly of the view that my overall condition merited an increase in points and award of benefit and therefore, it would be inappropriate to deprive me of entitlement on a technicality."

11. After considering the papers, I issued a direction observing that there was little doubt that the tribunal's decision must be set aside. The tribunal had erred in its application of regulation 11(4) of the General Benefit Regulations in that it had no authority to aggregate before making an assessment in respect of PDA8. However, in view of the complexities, I directed an oral hearing of the appeal.
12. Shortly before the hearing, a further submission was received from the Office of the Solicitor to the DWP that in the light of the medical nature of some of the points to be ventilated at the oral hearing, medical advice had been sought. Following receipt of that advice, the Secretary of State now took issue with the diagnosis of PDA8. If the evidence did support such a diagnosis, questions of causation arose and "other effective causes" needed to be considered. These being complex questions, it was also submitted that if a decision were to be needed on these points, the experience of a medically qualified appeal tribunal member would be beneficial. If necessary, therefore, I should remit the appeal to a freshly constituted appeal tribunal for a full rehearing with directions as to the assessment of PDA8. Dr Susan Reed medical Adviser to the DWP had prepared medical advice which was attached. She was prepared to attend the hearing, an offer which I accepted.
13. The oral hearing was duly held on 30 May, the claimant being present and supported by a friend. The respondent was represented by Mrs Gillian Jackson of the Office for the Solicitor for the DWP, and Dr Reed attended. I am grateful to everyone for their assistance, and particularly to the claimant who was faced with a large additional bundle of submissions from the Office of the Solicitor for the DWP without notice late on the morning of the hearing itself.
14. It was the Secretary of State's submission that three errors of law in the tribunal's decision had now been identified:

(a) There was no reasonable basis for a diagnoses of PDA8 in the claimant's case;

(b) Even if there were a proper basis, there was no proper assessment of causation and no findings on this point; and

(c) The approach and the assessment were in error.

In any event it was difficult to see how a finding had been made as to the extent of disablement when the tribunal recorded that the claimant had no symptoms at the time of the tribunal hearing, due to the recent injections which she had received.

15. Dr Reed amplified what are presently considered to be the causes and development of PDA8 and PDA12 as annexed to the Secretary of State's submission of 22 May 2007. In case this may be of more assistance more generally, and with her consent, I have attached this information as the Schedule to this decision. In summary, it was the Secretary of State's submission, on Dr. Reed's advice, that whilst the onset of PDA8 can be due to repetitive work, it must occur close in time to that repetitive work and would not manifest two years later.
16. The claimant explained how she had been troubled by her problems and that because of them she had been given an easier job within the company which did not involve the use of automatic screwdrivers. However, once the possibility of her instituting proceedings was time expired, her employers had moved her back to the factory floor. She had not been aware of the existence of industrial injuries disablement benefit until her union representative mentioned it to her, and she considered that if she had been seen in 1998 by doctors she would probably have succeeded. Her experience was that doctors acting on behalf of the DWP reported that she did not have PDA8 but doctors she had consulted separately had found that she did.
17. In answer to the points made by the claimant, Dr Reed gave evidence before me explaining the likely difference in approach between doctors providing evidence on claims, doctors sitting on tribunals and doctors consulted separately by claimants, in that the first two were assessing the extent of a claimant's disablement in the light of the doctors' specific expertise, whereas doctors consulted separately by claimants would be likely to consider the situation therapeutically - that is whether a claimant had the condition under consideration.
18. At the hearing I confirmed that, as indicated in my direction, there is no doubt that the tribunal's decision should be set aside. There is also now no doubt in my mind that the case would be best dealt with by being remitted to a tribunal, with the directions as set out in paragraph 3 above. One of the additional reasons for my wishing to have the benefit of Dr Reed's evidence at the hearing was so that, if appropriate, it might be incorporated in the decision for wider promulgation, which, in the event, I have done. It must be borne in mind that this is the current medical view as expressed on behalf of the Secretary of State, I am not in a position to make any medical comment thereon, and others may wish to do so at appropriate times.
19. For the reasons stated therefore, namely that the tribunal failed to apply the complex provisions of regulation11 of the General Benefit Regulations correctly the Secretary of State's appeal succeeds. My decision set out in paragraph 1 and my directions in paragraph 2.

(signed on the original) E A Jupp

Commissioner

25 July 2007

THE SCHEDULE

Prescribed Disease A8

Tenosynovitis (Also referred to as tenovaginitis)

20. Skeletal muscles are muscles which cause the joints to move. The muscle is attached to the bones at either side of the joint it moves by fibrous tissue.
21. Each muscle has an origin – i.e. the start of the muscle, or where it arises, and an insertion, i.e. the end where it joins to bone at the other side of the joint.
22. When a muscle contracts it shortens thereby pulling the joint in the direction of the bone where it has its origin. For example the muscle, which bends the knee, has its origin on the pelvis and its insertion at the tibia.
23. Although the fibrous tissue at the origin of a muscle is usually very short, that at its insertion can be very long. These fibrous connections are known as tendons.
24. In some places in the body this tendon needs protection (e.g. because it runs closely over bone, or is close to the surface). In these cases the tendon has a fibrous sheath (like a tunnel) through which the tendon runs. This tendon sheath is lined with cells, like the ones round within joints, which produce a lubricant, thereby allowing the tendon to move easily in the sheath when the muscle contracts and relaxes. This lining is known as synovial lining. Tendon sheaths occur for example at the wrist, at the ankle, at the shoulder.

Tenosynovitis

25. This is inflammation of the synovial lining of the tendon sheath, but the enclosed tendon may also subsequently become inflamed. It is a general term and thus a medical diagnosis of "tenosynovitis" therefore does not necessarily equate to a diagnosis of PD A8 as the muscle tendon and its sheath affected are not necessarily muscles and tendons of the hands and forearms.
26. The common sites for tenosynovitis are the wrist and the ankle, but other tendon sheaths may be affected elsewhere in the body.

Causes of Tenosynovitis

27. Often the cause of Tenosynovitis is unknown. There are several known causes, including:

trauma

Rheumatoid Arthritis

Infection, eg gonococcal infection etc

repetitive movements

Tenosynovitis of the hand or forearm

28. Tenosynovitis of the hand or forearm is a common condition, and a diagnosis of it may be made in the absence of any occupational causation.
29. Tenosynovitis of the hand or forearm affects:

•    the tendons of the abductor pollicis longus and extensor pollicis brevis, which share a common sheath at the thumb side of the wrist. These muscles arise (i.e. have their origin) in the forearm, and insert into the thumb to make it move. This type of tenosynovitis is often referred to as de Quervain's disease or de Quervain's tenosynovitis.

•    the flexor tendons- flexor carpi radialis or flexor carpi ulnaris, both of which arise in the forearm and insert into the wrist bones and are the tendons of the muscles which bend (flex) the wrist.

30. The clinical findings in Tenosynovitis in the wrist and forearm are:

•    Pain on movement over the dorsal aspect (i.e. back of) the hand or the wrist depending on which muscle tendon is affected especially when the person undertakes repetitive movements.

•    Swelling due to accumulation of fluid in the sheaths

•    Crepitus, which can be felt and or heard (a feeling and sound like crumpling cellophane) due to the tendon rubbing against the swollen sheath.

•    Calcium deposits may be visible on x-ray.

31. Treatment:

•    With rest the symptoms usually settle

•    Local steroid injection

•    Severe cases may need operative treatment.

32. Although it causes pain, the person is capable of performing normal or virtually normal functions of the hands and wrists.

Differential diagnosis

33. When making the diagnosis the clinician must consider other diagnoses (i.e. consider the differential diagnosis). Other causes of wrist pain should be considered, e.g. arthritis, infection etc as well as referred pain, i.e. pain which although felt in the wrist or hand originates from pathology elsewhere, e.g. the neck or shoulder.

Prescribed Disease A8

34. Traumatic inflammation of the tendons ('tenosynovitis') due to occupational causes develops as a result of direct trauma to the tendon or by repetitive movements. The longer the interval between ceasing the occupation and the development of symptoms, the less likely it is that the occupation caused those symptoms. Thus if symptoms develop months or years after the occupation ceased, then the cause is not the work, and thus PD A8 cannot be accepted on causation.

Carpal Tunnel Syndrome and Prescribed Disease A12

Carpal Tunnel Syndrome

35. The Median nerve enters the hand by passing through a tunnel formed by the convex anterior surface of the carpal bones and a ligament -the flexor retinaculum. As well as the Median nerve, the flexor tendons (i.e. the tendons which bend the fingers) of the fingers run through this tunnel. This is known as the Carpal Tunnel. The Ulnar and Radial nerves do not enter the hand via this tunnel.
36. Alterations in any of the anatomical structures in the tunnel can result in a loss of volume in the available space (which at best is limited) in the carpal tunnel and so produce compression of the median nerve: Carpal Tunnel Syndrome

Aetiology

37. Carpal tunnel syndrome is caused by compression of the median nerve as it passes deep to the flexor retinaculum. However in relation to the use of vibrating tools, the pathology may be due to physical trauma to the nerve itself and/or blood vessels to the nerve, which may explain the poor results with carpal tunnel decompression in patients with vibration induced Carpal Tunnel Syndrome
38. Carpal Tunnel Syndrome is very common in the population as a whole, and it is more common in women than men. In women it occurs in 7 per 100 and in men 1 per 100.
39. Most cases of Carpal Tunnel Syndrome arise spontaneously (i.e. there appears to be no trigger causing it).
40. In 30% of cases there is an underlying medical condition:

•    It may follow prolonged use of the wrist by arthritic patients who need to use a walking stick.

•    Swelling of the tendons due to a tenosynovitis, e.g. Rheumatoid arthritis produces an inflammatory tenosynovitis of the flexor tendons or synovitis of the wrist joint. Carpal Tunnel Syndrome may also be associated with previous serious trauma, such as Colles' fracture or subluxation of the lunate (one of the carpal bones).

•    Osteoarthritis of the wrist or ganglion formation.

•    It may also occur during the last trimester of pregnancy or as part of the premenstrual syndrome, presumably due to fluid retention.

•    Various metabolic diseases, including gout, hypothyroidism, acromegaly, fluid retention in renal disease or amyloidosis.

•    Exposure to vibration.

•    Overuse of the wrist, e.g. in actions which involve repeated flexion and extension of the wrist. In its recent report the Industrial Injuries Advisory Council (IIAC) reported that in order to develop Carpal Tunnel Syndrome the repeated flexion and extension should occur every 30 seconds or more often for at least 20 hours per week, and the duration of the qualifying employment should exceed a year.

41. Because the condition is so common, and can have different causes each case needs careful evaluation to establish the actual cause (if any is identifiable) in an individual patient.
42. If vibration is claimed as the cause of Carpal Tunnel Syndrome, a history of vibrating tool use within a particular occupation should be elicited. The following should be noted:

•    Vibrating tool type.

•    Wrist posture whilst using the tool.

•    Weight of the tool.

•    Frequency and duration of tool use.

•    Effects of change of job role/occupation to avoid the use of vibrating tools.

•    Relationship of onset of symptoms to use of tools.

43. If repeated flexion and extension (palmar and dorsiflexion) is claimed as the cause of the Carpal Tunnel Syndrome the following should be noted:

•    Wrist posture whilst performing work.

•    Frequency and duration of palmar and dorsiflexion whilst performing work.

•    Effects of change of job role/occupation to avoid the action.

•    Relationship of onset of symptoms to occupation.

•    Tool type and weight of the tool (if any involved in task).

•    Wrist posture whilst using the tool.

NB: IIAC considered the use of keyboards and mouse and advised that there was insufficient evidence to include keyboard and mouse use in the prescription of PD A12.

Symptoms of Carpal Tunnel Syndrome

44. Symptoms are:

•    The patient is usually a middle-aged female and one or both hands, but more commonly the dominant hand, may be involved.

•    Paraesthesias (tingling, numbness, pins and needles, burning) in the parts of the hands supplied by the Median nerve especially at night, and are often relieved by the patient moving the hands about or by hanging them over the edge of the bed or above the shoulder.

•    The symptoms are characteristic and are most severe at night, when it commonly disturbs the patient's sleep.

•    The patient may also complain of an unpleasant sensation of fullness or stiffness in the fingers, especially in the morning, or that the fingers feel clumsy or weak.

Clinical signs and investigations of Carpal Tunnel Syndrome

45. Clinical signs are:

•    The patient's symptoms may be reproduced by various manoeuvres that are designed to produce increased compression of the median nerve in the carpal tunnel. This may be achieved by the examiner placing his thumb over the patient's wrist and then fully flexing the patient's hand for approximately 1 minute. Alternatively, both wrists may be held fully flexed by compressing the dorsal surfaces of the hands together (Phalen's sign). Phalen's test positive – parathesia in median nerve distribution within 60 seconds of full wrist flexion (sensitivity 75%, specificity 95%).

•    Tapping (or percussion) over the Median nerve at the wrist (Tinel's test or sign) may also reproduce the patient's symptoms. Tinel's test positive – parathesia in median nerve distribution when percussing over the carpal tunnel. Parathesia must be felt distal to the point of pressure for a positive test (sensitivity 64%, specificity 99%). (NB Tinel's test is also used to test other nerves, e.g. the Ulnar nerve by tapping over the Ulnar nerve as it enters the hand at the wrist).

•    A neurological examination of the hand to determine any loss of sensation in the fingers, by using a pin prick and the two-point discrimination test.

•    Wasting of the thenar eminence, i.e. the part of the palm below the thumb.

•    Weakness in opposition or abduction of the thumb.

•    Examination of the whole of the upper limb and neck is also necessary to exclude a more proximal cause of an entrapment neuropathy. Symptoms of the carpal-tunnel syndrome may be confused with a cervical spondylosis, or the two conditions may occur together.

•    In clinical practice nerve conduction studies using sensory and motor latencies may be carried out and a comparison made with either the normal limb or with conduction in the ulnar nerve. It is not essential to carry out nerve conduction studies if the diagnosis can be made on the basis of the history and clinical findings.

•    It may be necessary to exclude any underlying metabolic disorder or space-occupying lesions of the carpal tunnel by using appropriate investigations (e.g. blood tests, xrays).

Diagnosis

46. Diagnosis is often made clinically from characteristic symptoms and signs. Nerve conduction studies may have been performed.

Treatment

47. Treatment may include one or more of the following list. The effects of a particular treatment should be noted.

•    Rest to the wrist. This may require a volar splint that is worn with the wrist held in the neutral position and includes the flexed fingers. It may be worn at night only, or continuously if symptoms are severe.

•    Injections. An injection of a long-acting corticosteroid into the carpal tunnel is a simple procedure that usually produces significant symptomatic relief within a day. This injection usually produces such good symptomatic relief that it may also be used as a diagnostic test.

•    Mobilization. Passive movements aimed at stretching the flexor retinaculum and improving the posteroanterior range of the intercarpal joints may be useful.

•    Decompression of the carpal tunnel. Surgery is indicated if:

(a) Conservative methods fail (i.e. the methods described above);

(b) Repeated injections are necessary at frequent intervals;

(c) Severe motor impairment of the muscles of the thenar eminence is present.

NB Anti-inflammatory drugs rarely provide any relief of symptoms. Physical methods – such as heat, exercise or massage – have no role in the treatment of this condition.

Functional effects

48. Consider activities affected by reduced grip and dexterity within the typical day history such as dressing, shaving, hobbies, driving, playing a musical instrument. A clear description of the claimed effects and clinical findings to support the history of the functional effects is necessary to assess disablement.

Due to the nature of

49. Unlike many other Prescribed Diseases Carpal Tunnel Syndrome is not presumed to be due to the nature of the occupation. Therefore once Carpal Tunnel Syndrome has been diagnosed, an opinion must be given as to whether the disease is due to the nature of the occupation, on the balance of probability. Consider the following:

•    The degree of the occupational factors outlined above.

•    Relationship of symptoms to vibrating tool use.

•    Other causes of Carpal Tunnel Syndrome independent of vibration and repetitive movements – pregnancy, oral contraception, diabetes mellitus, osteoarthritis of carpus, rheumatoid arthritis, myxoedema etc.

•    Likely degree of contribution of other conditions (in whole or part).