P39 Physiotherapy management of long thoracic nerve injury (LTNI) post-flu vaccine in an immunocompromised patient with vasculitis: what is the best strategy?

Abstract

Abstract Background We describe the case of a 12 year-old boy with polyarteritis nodosa presenting with long thoracic nerve injury (LTNI) post flu vaccination. Polyarteritis nodosa is an inflammatory vasculitis treated with immunosuppressive medication. Children with immunosuppression require seasonal flu vaccination, and LTNI is a recognised complication, rare in children, with no incidence documented. Physiotherapy plays a role in the conservative management of LTNI, however, there is debate regarding the most effective regime. Methods Case description with literature review of aetiology, treatment strategies and recommendations for effective therapeutic approach. Results Our patient was diagnosed with polyarteritis nodosa following an admission with intra-abdominal bleed, coeliac axis thrombosis and mesenteric artery aneurysm seen on angiogram. He responded well to steroids and immunosuppressive medication. Due to the risk of infection from immune suppression, he received seasonal intra-muscular influenza vaccination to the right deltoid. There were no initial complications, however, two weeks later, burning shoulder pain and sleep disturbance were reported. There was paraesthesia in the right hand although grip strength was not impaired. Of note, the patient is left hand-dominant. Examination revealed elevation of the right shoulder girdle and winging of the medial border of the scapula. Range of movement at the shoulder was full and pain-free. Palpation of the gleno-humeral joint line and deltoid were unremarkable. The clinical findings suggested long thoracic nerve denervation. Physiotherapy assessment demonstrated weakness in the serratus anterior muscle and abnormal scapula movement patterns, including decreased protraction. Nerve conduction studies reported decreased activation of the long thoracic nerve. Scapula recruitment exercises were advised, as well as posture correction. After a year, scapula-humeral rhythm and strength of the scapula muscles improved. Conclusion Causes of scapula-winging in children include osteochondromas, exostoses and sports-related injuries. Scapula-winging associated with LTNI is a recognised complication of flu vaccine but very rarely reported in under 16-year olds. Treatment of LTNI is poorly evidenced in the literature. However, physiotherapy including bracing to enhance proprioception, mobility exercises in supine to correct scapula position and strengthening of scapula muscles is reported. There is a lack of evidence to inform the most effective approach. The literature outlines that general gleno-humeral muscle strengthening is beneficial in improving shoulder function in LTNI. However, there is limited research investigating the specific role of scapula muscle strengthening in LTNI in children. The literature suggests that poor scapula function can impair the biomechanics of the shoulder and exercises that address scapula muscle control can improve movement patterns. The time to recovery from LTNI is estimated between 1-2 years and maintaining muscle bulk is our challenge, as the nerve recovers. Clinicians need to be aware of LTNI complicating flu vaccine in immuno-compromised children. We highlight the importance of physiotherapy in improving scapula biomechanics. Conflicts of Interest The authors declare no conflicts of interest.