Abstract
Objective: To describe Sniff Nasal Inspiratory Pressure (SNIP) a new way of assessing the global respiratory function in scoliosis patients and explain it’s particular relevance in neuromuscular scoliosis. To correlate of SNIP with conventional lung function tests in scoliosis patients. To compare SNIP values between patients with neuromuscular and idiopathic scoliosis.
Design: A prospective observational study of 36 scoliosis patients. All patients underwent conventional lung function tests and SNIP during their pre-operative assessment. The SNIP values were correlated with FVC and FEV1 values obtained by spirometry. The SNIP values of those with neuromuscular scoliosis were compared to those with idiopathic scoliosis and also with the normative data of general population.
Subjects: Thirty-six patients (13M, 23F) with scoliosis. Of them, 17 (1M, 16F) had idiopathic scoliosis and 19 (12M, 7F) had neuromuscular scoliosis. The mean age was 16.5 years (7–54).
Outcome Measures: Comparison of the mean SNIP, FEV1, FVC and FEV1/FVC between the idiopathic and neuromuscular group. Assessing the degree of correlation between SNIP and spirometry data for all patients.
Results: Overall mean SNIP was 50.22 cm H2O. Average SNIP in the neuromuscular group was 40.92±11.68 and 58.72±21.96 in the idiopathic group (p=0.0127). While the mean FEV1 (p=0.183), FVC (p=0.191) and FEV1/FVC (p=0.721) values were not significantly different between the two groups. The correlation coefficient for spirometry values and SNIP was −0.577 (mean x=−48.86, mean y=1.87) (p=0.0002), indicating very good correlation.
Conclusion: SNIP is the best measure of global inspiratory muscle strength and less subjective than spirometry. It is easier to administer to children. SNIP is better able to distinguish between idiopathic and neuromuscular scoliosis patients, than spirometry and shows good correlation with spirometry values. It can be a useful test in assessment and follow-up of breathing in neuromuscular scoliosis patients.
The abstracts were prepared by Mr Peter Millner. Correspondence should be addressed to Peter Millner, Consultant Spinal Surgeon, Orthopaedic Surgery, Chancellor Wing, Ward 28 Office Suite, St James’ University Hospital, Beckett Street, Leeds LS9 7TF.
