RESEARCH REPORT PLATFORM PRESENTATION

DECREASED NECK MUSCLE ENDURANCE IN NON-SPECIFIC NECK-PAIN PATIENTS AND IN PATIENTS AFTER ANTERIOR CERVICAL DECOMPRESSION AND FUSION. Peolsson A, Kjellman G; Dept of Health and Society, Div of Physiotherapy, Faculty of Health Sciences, Linköping University, Linköping, Sweden

PURPOSE: To investigate differences in ventral and dorsal neck muscle endurance (NME) among patients with non-specific neck pain (NP) or cervical disc disease (ACDF) and healthy controls (C). RELEVANCE: There is no knowledge of proportions of patients with disability of NME either before or after treatment for neck disorders. Furthermore there is no knowledge if there are differences in NME between NP and ACDF patients. PARTICIPANTS: NME was measured in NP (n=77) and ACDF (n=34) patients before treatment and at 12-month follow-up and results was compared to gender-specific reference values from C (n=116) both on individual and group levels. METHODS: Ventral and dorsal NME was measured in seconds in a standardized and reliable manner in lying down position. Neck pain on Visual Analogue Scale and neck specific disability (NDI) were obtained. NP, and after anterior cervical decompression and fusion also ACDF group were treated polyclinically by physiotherapists. ANALYSIS: Statistical significance within and between groups was analyzed by paired and unpaired two-tailed Student’s t-test and by factorial Analysis of Variance with the Bonferroni/ Dunn post-hoc test. Deficit in NME on individual level was defined as>1 Standard Deviation below the gender specific mean value of the control group and on group level defined as below 95% lower Confidence Interval (CI). Pearson correlation coefficient analysis was used to investigate relationship between NME and pain intensity or NDI. Significance was accepted at a level of p < 0.02 in the ANOVA and otherwise p < 0.05. RESULTS: Patients had mainly significantly (p < 0.01) decreased NME compared with C. ACDF women had lower ventral NME than NP women (p < 0.01). 29-100% of patients had disability (>1 SD below mean of C) in NME, mainly with group mean below 95% CI of C. Only NME in NP women (p < 0.05) improved after treatment. Flexion/ extension ratio normalized after treatment in NP (p = 0.36) but not in ACDF (p < 0.0001). NME in ACDF group correlated with both pain intensity and neck specific disability (NDI) (r = −0.51 to −0.78, p < 0.01). NME in NP group were mainly uncorrelated to pain but mainly weakly correlated to NDI (−0.31 to −0.38, p < 0.02). CONCLUSIONS: A great deal of patients had impairment in NME before, but also after treatment. IMPLICATIONS: Specific training of NME and longer treatment period may improve outcome and should be taken into consideration in clinical practice. KEYWORDS: Neck muscles, physical endurance, treatment. FUNDING ACKNOWLEDGEMENTS: This study was supported by the Faculty of Health Sciences, Linköping University. CONTACT: anneli.peolsson@ihs.liu.se

ETHICS COMMITTEE: Linköping Ethics Committee