Evidence-based systematic review.
To define the optimal treatment of fractures involving the C2 body, including those with concomitant injuries, based upon a systematic review of the literature.
Axis body fractures have customarily been treated nonoperatively, but there are some injuries that may require operative intervention. High-quality literature is sparse and there are few class I or class II studies to guide treatment decisions.
A literature search was conducted using PubMed (MEDLINE), Cochrane Central Register of Controlled Trials, and Scopus (EMBASE, MEDLINE, COMPENDEX). The quality of literature was rated according to a grading tool developed by the Center for Evidence-based Medicine. Operative and nonoperative treatment of axis body fractures were compared using fracture bony union as the primary outcome measure. As risk factors for nonunion were not consistently reported, cases were analyzed individually.
The literature search identified 62 studies, of which 10 were case reports which were excluded from the analysis. A total of 920 patients from 52 studies were included. The overall bony union rate for all axis body fractures was 91%. Although the majority of fractures were treated nonoperatively, there has been an increasing trend toward operative intervention for Benzel type III (transverse) axis body fractures. Nearly 76% of axis body fractures were classified as type III fractures, of which 88% united successfully. Nearly all Benzel type I and type II axis body fractures were successfully treated nonoperatively. The risk factors for nonunion included: a higher degree of subluxation, fracture displacement, comminution, concurrent injuries, delay in treatment, and older age.
High rates for fracture union are reported in the literature for axis body fractures with nonoperative treatment. High-quality prospective studies are required to develop consensus as to which C2 body fractures require operative fixation.
*Rothman Institute & Thomas Jefferson University Hospital
†Thomas Jefferson University Hospital, Philadelphia, PA
‡Rush University Medical Center
§Northwestern Memorial Hospital, Chicago, IL
∥The CORE Institute, Phoenix, AZ
¶Massachusetts General Hospital, Boston, MA
#Department of Orthopaedic Surgery, University of Washington, Seattle, WA
**Department of Neurosurgery, University of Maryland, Baltimore, MD
††Department of Neurosurgery, University of Pittsburgh, Pittsburgh, PA
‡‡Department of Neurosurgery, University of Kansas, Kansas City, KS
§§Department of Neurosurgery, University of Toronto, Toronto, ON, Canada
∥∥Mayo Clinic, Rochester, MN
¶¶Department of Neurosurgery, University of Virginia, Charlottesville, VA
##Department of Orthopaedic Surgery, Emory University, Atlanta, GA
***Department of Orthopaedic Surgery, University of British Columbia, Vancouver, BC, Canada
A.R.V. received royalties from DePuy, IV electronics, Stryker Spine, Biomet Spine, Globus, Aescuiap, Nuvasive; owned stocks from Replication IVledica, Globus, K-2 Medical, Paradigm Spine, Stout Medical, Spine Medica, Computational Biodynamics, Progressive Spinal Technologies, Spinology, Small Bone Innovations, Cross Current, Syndicom, In Vivo, Flagship Surgical, Advanced Spinal Intellectual Properties, Cytonics, Bonovo Orthopaedics, Electrocore, Gamma Spine, Location Based Intelligence, FlowPharma, R.S.I., Rothman Institute and Related Properties, Innovative Surgical Design, Spinicity; consulting for Stout Medical, Gerson Lehrman Group, Guidepoint Global, Medacorp, Innovative Surgical Design, Orthobullets; was in the Board of Directors for AOSpine, Innovative Surgical Design, Association of Collaborative Spine Research, Spinicity; and received grants from Stryker Spine, Nuvasive, Cerapedics. V.C.T. received royalties from Medtronic; had speaking and teaching agreements with Medtronic; received research support from Medtronic; received grants from NIH; received fellowship support from Globus. A.A.P. received royalties from Amedica and Ulrich; private investment from Medica, Cytonics, Nocimed; consulting for Amedica, DePuy, Biomet, Stryker, GE Healthcare, and Zimmer; and was in the Board of Driectors for CSRS and LSRS. M.B.D. received royalties from Mayo Office Of Intellectual Property/Medtronic; consulting for Depuy and Medtronic; speaking/teaching for Depuy and Medtronic; and received research support from Medtronic. J.H. did consulting for Depuy and Bioventus; received grants from NACTN; and received fellowship support from AOSpine. K.B.W. had stock ownership at TransS1; received research support from K2M and Synthes; received grants from NIH; and received fellowship support from OREF, Globus, AOSpine. R.B. did speaking or teaching for AOSpine; received research support from Synthes; and received fellowship support from AOSpine and Depuy. P.M.A. had stock ownership at Z Plasty; did consulting for Medtronic, Lifespine, Integra life, SpineWave, Stryker Spine, MIEMS, AOSpine NA, Cerapedics; did speaking/teaching for University of Missouri; was in the Board of Directors for AOSpine; and received grants from AOSpine. A.N. received grants from OREF, CSRS, AOSpine and received fellowship support from AOSpine, North America. C.S. received royalties from Medtronic and Biomet; did consulting for Medtronic, Biomet, Globus, NuVasive, Stryker; received grants from NIH, DOD, AO, NREF, NACTN; and received fellowship support from NREF, AO, UVA. S.T.Y. received royalties from Stryker, Meditech; owned stocks at Alphatech, Meditech and Medyssey; did consulting for Stryker; and was in the Scientific Advisory Board for ISSLS, TSJ. The remaining authors declare no conflict of interest.
Reprints: Gregory D. Schroeder, MD, Rothman Institute & Thomas Jefferson University Hospital, 925 Chestnut Street, 5th Floor, Philadelphia, PA 19107 (e-mail: email@example.com).
Received October 6, 2014
Accepted June 12, 2015