An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Zwart JA, Helseth E, Skaanes KO.Zwart JA, et al.Tidsskr Nor Laegeforen. 1994 Oct 10;114(24):2845-7.Tidsskr Nor Laegeforen. 1994.PMID: 7998032Norwegian.
Heuch I, Hagen K, Heuch I, Nygaard Ø, Zwart JA.Heuch I, et al. Among authors: zwart ja.Spine (Phila Pa 1976). 2010 Apr 1;35(7):764-8. doi: 10.1097/BRS.0b013e3181ba1531.Spine (Phila Pa 1976). 2010.PMID: 20228714
Heuch I, Heuch I, Hagen K, Zwart JA.Heuch I, et al. Among authors: zwart ja.Spine (Phila Pa 1976). 2013 Jan 15;38(2):133-9. doi: 10.1097/BRS.0b013e3182647af2.Spine (Phila Pa 1976). 2013.PMID: 22718225
Heuch I, Heuch I, Hagen K, Zwart JA.Heuch I, et al. Among authors: zwart ja.PLoS One. 2015 Oct 27;10(10):e0141268. doi: 10.1371/journal.pone.0141268. eCollection 2015.PLoS One. 2015.PMID: 26506618Free PMC article.