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.
Mannherz RE, Betz RR, Clancy M, Steel HH.Mannherz RE, et al. Among authors: betz rr.Spine (Phila Pa 1976). 1988 Oct;13(10):1087-90. doi: 10.1097/00007632-198810000-00003.Spine (Phila Pa 1976). 1988.PMID: 3206264
Ward M, Betz RR, Clements DH, Cole BA.Ward M, et al. Among authors: betz rr.Spine (Phila Pa 1976). 1997 Feb 15;22(4):406-7. doi: 10.1097/00007632-199702150-00010.Spine (Phila Pa 1976). 1997.PMID: 9055368