Clinical Intelligence

Daniel P Butler, Alice Murray and Maxim Horwitz

Hand manifestations of neurological disease: some alternatives to consider

Patients with a systemic neurological deletion of a segment of chromosome disease can often first present with 17p11.2-12 there is inadequate production symptoms and signs affecting the hand. of myelin with reduced myelination of both With limited time to review patients in clinic, sensory and motor nerves.3 Minor trauma the symptoms can often be attributed to such as stretching or pressure from traction common hand disorders, such as carpal or repetitive movement results in focal tunnel syndrome (Figure 1). The aim of this demyelination. As a result of the myelin article is to review a few of the common deficiency repair is poor and the nerve is systemic neurological disorders that may then more susceptible to further injury. In first present with manifestations in the hand. the upper limb the median and ulna nerves A secondary goal would be to prevent the are commonly affected. Symptoms can be surgical treatment of hand conditions that as mild as occasional numbness but can are more amenable to systemic treatment progress to true sensory deficit with motor if appropriately managed. weakness. The diagnosis can be confirmed through MOTOR NEURONE DISEASE genetic testing and nerve conduction testing. Motor neurone disease (MND) can present Electromyographs confirm the disease with with both upper and lower motor neurone the bilateral slowing of sensory and motor signs. The terminology attributed to the nerve conduction at the carpal tunnel with disorder is subdivided between upper at least one additional abnormal finding for (primary lateral sclerosis) and lower motor conduction in one peroneal nerve.4 motor neurone (progressive and spinal The importance of clarifying the diagnosis musclular atrophies) or both (amyotrophic is that decompression is controversial and lateral sclerosis). Onset of the disease is may only provide short-lived relief. Patients usually in the mid-50s with an incidence of are likely to experience recurrent symptoms 1–2:100 000. following decompression and may undergo In the hand, the lower and combined further unnecessary surgery if there is motor neurone types may first present with concern that incomplete decompression wasting of the thenar muscles. Typically it has been performed. On a final note, if is the abductor pollicis brevis (APB) muscle the patient is undergoing anaesthesia that is first to be affected. Based on such a meticulous attention must be paid to presentation, it would be understandable prevent pressure on any nerves that may for the diagnosis of carpal tunnel syndrome cause further palsies. Daniel P Butler, MRCS(Eng), plastic surgery to be made despite the absence of sensory registrar; Alice Murray, MRCS(Eng), general signs. DYSTONIA surgery registrar; Maxim Horwitz, FRCS(Orth), consultant hand surgeon, Department of Hand Subsequent to the weakening of the thenar This condition involves an initial repetitive Surgery, Chelsea and Westminster Hospital, muscles, the first dorsal interosseous (FDI) involuntary movement followed by London. muscle is next affected.1 This is referred abnormal posturing of muscles and Address for correspondence to as the ‘split hand’ as the radial aspect can involve the face (blepharospasm), Daniel P Butler, Department of Hand Surgery, of the hand is far more affected than the neck (spasmodic torticollis), and hands. Chelsea and Westminster Hospital, 369 Fulham 2 Road, London SW10 9NH, UK. ulna aspect. The muscle atrophy eventually It is thought that the balance between E-mail: [email protected] progresses proximally with diminished the excitation and inhibition of muscles Submitted: 11 January 2016; Editor’s tendon reflexes. is disrupted and this then leads to the response: 13 February 2016; final acceptance: co-contraction of antagonistic muscles.5 17 February 2016. HEREDITARY NEUROPATHY WITH This can be painful during as well as after ©British Journal of General Practice 2016; LIABILITY TO PRESSURE PALSIES (HNPP) the abnormal posturing. 66; 331–332. DOI: 10.3399/bjgp16X685549 This condition typically presents between In the hand this condition is usually task 30 and 40 years of age. As a result of the specific and can be so debilitating that it

British Journal of General Practice, June 2016 331 Figure 1. An anteroposterior and lateral clinical CONCLUSION photograph of the right hand of a patient with At medical school, students are often Charcot-Marie Tooth disease. Note the thenar taught to begin a systematic examination by flattening with preservation of hypothenar muscle looking at the hands. In the case of a patient bulk. Sensory deficit was most notable in the radial presenting with neurological symptoms three digits. The changes were unilateral. An initial affecting the hand the reverse is true. diagnosis of carpal tunnel syndrome had been made. The clinician should consider the possible diagnoses of a systemic neurological disease such as those presented. Careful history and examination supplemented with appropriate investigations such as electromyography, nerve conduction studies, and magnetic resonance imaging can aid the diagnosis. In reality, most apparent compressive neuropathies and radicular pains will prove to be just that. However, in those patients with a systemic neurological disease, a systematic approach can avoid patients undergoing unnecessary operative procedures. Instead, patients can be correctly diagnosed and treated at the earliest possible opportunity. may cause a patient to lose their job. These occupations include guitar playing, piano Provenance playing, writing, and typing.6 It is unclear Freely submitted; externally peer reviewed. what the exact aetiology for the condition is but there is a genetic as well as an Competing interests occupational or repetitive task disposition The authors have declared no competing to it. It is a clinical diagnosis and does not interests. require special tests. Acknowledgements The management of this condition Mr Elliot Sorene and Miss Emma Taylor — includes therapy with retraining of muscles for their support during the completion of as well as mirror box exercises. This can the Diploma in Hand Surgery. be combined with behavioural sessions. Botulinum toxin is also used under EMG Discuss this article guidance to weaken the antagonistic Contribute and read comments about this muscles. article: bjgp.org/letters

MULTIPLE SCLEROSIS This complex disease has a frequency of 100 per 100 000 people. It is thought to be related to central demyelination and it REFERENCES 1. Kuwabara S, Sonoo M, Komori T,et al. can have multiple presentations from acute Dissociated small hand muscle atrophy in progressive to chronic and relapsing types. amyotrophic lateral sclerosis: frequency, A key point is that a patient may present with extent, and specificity. Muscle Nerve 2008; symptoms and signs that are disseminated 37(4): 426–430. in time and anatomical location. 2. Wilbourn AJ. The ‘split hand syndrome’.Muscle Nerve 2000; 23(1): 138. Multiple sclerosis can affect both the 3. Meier C, Moll C. Hereditary neuropathy with sensory and motor systems. It is possible liability to pressure palsies. Report of two that the first area to be affected is the hand. families and review of the literature.J Neurol Again, the diagnosis of median or ulnar 1982; 228(2): 73–95. nerve compression could be made at this 4. Mouton P, Tardieu S, Gouider R,et al. presentation, thus delaying the underlying Spectrum of clinical and electrophysiologic features in HNPP patients with the 17p11.2 diagnosis. Other hand signs include an deletion. Neurology 1999; 52(7): 1440–1446. intention and postural tremor, and there 5. Lin PT, Hallett M. The pathophysiology of may also be clonus and spasm. Careful focal hand dystonia. J Hand Ther 2009; 22(2): evaluation for other systemic neurological 109–113, quiz 114. symptoms or signs should be undertaken. 6. Frucht SJ. Focal task-specific dystonia of the Management is predominantly medical and musicians’ hand — a practical approach for surgery should not be attempted without a the clinician. J Hand Ther 2009; 22(2): 136–142, quiz 143. definite achievable goal.

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