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.
Newton PO, Marks MC, Bastrom TP, Betz R, Clements D, Lonner B, Crawford A, Shufflebarger H, OʼBrien M, Yaszay B; Harms Study Group.Newton PO, et al. Among authors: betz r.Spine (Phila Pa 1976). 2013 Feb 15;38(4):328-38. doi: 10.1097/BRS.0b013e31826c6df4.Spine (Phila Pa 1976). 2013.PMID: 22869062
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
Clements DH, Morledge DE, Martin WH, Betz RR.Clements DH, et al. Among authors: betz rr.Spine (Phila Pa 1976). 1996 Mar 1;21(5):600-4. doi: 10.1097/00007632-199603010-00013.Spine (Phila Pa 1976). 1996.PMID: 8852316
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