Isolated Serratus Palsy: Long-term Outcome in 85 Patients

Authors: Veera Pikkarainen, Martti Vastamäki

References: Presented at ICSES 2010

Introduction: Treatment strategies for serratus palsy vary greatly, and research data on the long-term outcome of this condition are few. Our main aim was to discover the natural course of serratus palsy and its long-term outcome after conservative treatment.

Patients and methods: We evaluated 85 patients with isolated serratus palsy (60 males) on average 20 (3-39) years after the onset of symptoms. In 24 patients with grade I or II palsy, only thoughtful observation was adopted (GI), and 56 were treated by means of a scapular protecting brace (GII).

Results: Mean age at onset of symptoms was 31 (11-52) years. The most common etiological factors were heavy exertion in 53 patients and injury in 33. 91% of the patients were right-handed, and paresis occurred in 87% on the right side. In GI, 13 patients (54%) recovered fully on average in 16 months, and in GII 28 (50%) in 22 months. In GI, 3 (13%) patients still had complete or almost complete scapular winging, and in GII, 9 (16%). Due to serratus palsy, 22 patients (26%) had had to retrain or retire from their work. This was significantly more usual among manual workers than among office workers (45% vs. 7%). At the final clinical examination, 27% of manual workers still had total palsy compared to 4% of office workers. A marked proportion of the victims (14%) failed to recover.

Conclusions: Heavy physical work seems to be both an important etiologic and a prognostic factor for serratus palsy. Another important prognostic factor is severity (grade) of the disease. Due to the less than favourable results of this long- term follow-up, we should at least warn patients expect less than full recovery.