Indian Journal of Medical Sciences Medknow Publications on behalf of Indian Journal of Medical Sciences Trust ISSN: 0019-5359 EISSN: 1998-3654 Vol. 58, Num. 3, 2004, pp. 131-132

Indian Journal of Medical Science Vol. 58 No. 3, March 2004 , pp. 131-132

Letter to Editor

SPONTANEOUS REDUCTION OF POSTERIOR SHOULDER DISLOCATION FOLLOWING REPEATED EPILEPTIC SEIZURES

B Sankar, ABY NG, A S Rameto , Ali F, M S Bell

Trauma & Orthopaedic Services, Royal Albert Edward Infirmary, Wigan Lane, Wigan WN1 2NN, UK.
E-mail: bijusankar@hotmail.com

Code Number: ms04020

Sir,

Early diagnosis, prompt reduction and adequate rotator cuff exercises are vital in preventing recurrent instability following shoulder dislocation.¹ We present a case of posterior shoulder dislocation and subsequent auto-reduction during two episodes of convulsive seizures, where the diagnosis could have easily been missed.

A 29-year-old healthy manual labourer presented to our Accident and Emergency department following two episodes of generalised convulsions. He noted that his left shoulder was extremely painful and stiff after the first seizure episode that `eased off' following the second one that occurred almost an hour later. There was no prior history of epilepsy or shoulder problems. Examination of his shoulders was unremarkable except for minimal loss of terminal internal rotation on the left side. An axillary radiograph revealed a large reversed Hill-Sachs lesion in the humeral head suggesting prior posterior dislocation of the shoulder. He was followed up regularly and underwent a course of physiotherapy to strengthen his rotator cuff muscles. At six months follow up, the shoulder was stable in all directions and in fact he then told us that he had returned to manual labour two weeks after the seizure episodes!

Here, the postulated mechanism of injury is posterior shoulder dislocation during the first episode of seizures that got reduced by anterior displacement of humeral head during the second episode. This kind of an auto-reduction of the shoulder is the first of its nature to be reported.

This case reveals that there is a subset of patients with epilepsy, whose shoulders dislocate and reduce during seizure episodes. This can happen in electrocution injury and electro-convulsive therapy also. The diagnosis of this potentially disabling injury was near to impossible due to lack of clinical findings in the case presented here. It is important not to miss this diagnosis, as recurrent shoulder instability occurs far less frequently with adequate seizure control and rotator cuff strengthening after prompt reduction (auto-reduction in this case) of the dislocation.¹ Excellent history given by the patient and the presence of a large reversed Hill Sachs lesion on axillary radiograph, the hallmark of prior posterior shoulder dislocation,² made the diagnosis possible.

This serves as a timely reminder for clinicians to obtain a thorough history and have a low threshold for obtaining antero-posterior and axillary shoulder radiographs in these patients with shoulder symptoms even when clinical examination is normal. It is also imperative to examine the contra-lateral shoulder and obtain radiographs if necessary, as there is a reported bilateral involvement in as many as 30%.³

References

1. Peterson SA. Posterior shoulder instability. Orthop Clin North Am 2000;31:263-74.
2. Ng B, Rix TE, Roy BR. Acute bilateral anterior dislocations of the shoulders. Ulster Med J 2000;69:171-2.
3. Shaw JL. Bilateral posterior fracture- dislocation of the shoulder and other trauma caused by convulsive seizures. J Bone Joint Surg 1971; 53A:1437-40.

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