Morphometric analysis of the uncinate processes of the cervical vertebrae
Abstract
Background: Uncinate processes (UPs) are distinct features unique to cervical vertebrae. They are consistently found on posterolateral aspect of the superior end plate of 3rd to 7th cervical vertebrae. In this study, we investigated the morphology of the UPs with a particular emphasis on the regional anatomy and clinical significance.
Materials and methods: The study included 63 vertebrae. The width, height and length of UPs were measured with a digital calliper. We also assessed inclination angle of UP relative to sagittal plane, angle between medial surface of UP and superior surface of vertebra, angle between long axis of the UP and frontal plane, angle between long axis of UP and sagittal plane.
Results: Average width of the UPs ranged from 4.25 mm at C3 to 6.33 mm at T1; average height ranged from 4.88 mm at T1 to 7.54 mm at C4; and average length ranged from 6.88 mm at T1 to 11.46 mm at C4. We measured the inclination angle of UP relative to sagittal plane, and found it to be relatively constant with T1 having the largest value. The average angle was 41.39°, and the range was 17° to 85°. The angle between the long axis of the UP and the sagittal plane was increasing significantly from C5 to T1. The average angle was 20.74° and the range was 6° to 65°.
Conclusions: Anatomy of UPs is significant for surgeon who operates on the cervical spine. Hopefully, the information presented herein would decrease complications during surgical approaches to the cervical spine
Keywords: uncinate processuncovertebral jointLuschka jointcervical spine
References
- Bland JH, Boushey DR. Anatomy and physiology of the cervical spine. Semin Arthritis Rheum. 1990; 20(1): 1–20.
- Bozbuğa M, Oztürk A, Ari Z, et al. Surgical anatomic evaluation of cervical uncinate process for ventral and ventrolateral subaxial decompression. Okajimas Folia Anat Jpn. 1999; 76(4): 193–196.
- Brismée JM, Sizer PS, Dedrick GS, et al. Immunohistochemical and histological study of human uncovertebral joints: a preliminary investigation. Spine. 2009; 34(12): 1257–1263.
- Browne KM. The anatomy, spatial relationships, and role of uncovertebral articulations as the source of posterolateral cervical cartilage sequestrations. J Neurosurg Spine. 2010; 12(3): 270–274.
- Cave AJ, Griffiths JD, Whiteley MM. Osteo-arthritis deformans of the Luschka jounts. Lancet. 1955; 268(6856): 176–179.
- Civelek E, Kiris T, Hepgul K, et al. Anterolateral approach to the cervical spine: major anatomical structures and landmarks. Technical note. J Neurosurg Spine. 2007; 7(6): 669–678.
- Clausen JD, Goel VK, Traynelis VC, et al. Uncinate processes and Luschka joints influence the biomechanics of the cervical spine: quantification using a finite element model of the C5-C6 segment. J Orthop Res. 1997; 15(3): 342–347.
- Del Sasso L, Mondini A, Brambilla S, et al. Operative treatment of cervicobrachialgia and vertigo due to uncovertebral joint arthritis. Ital J Orthop Traumatol. 1991; 17(4): 498–504.
- Ebraheim NA, Lu J, Biyani A, et al. Anatomic considerations for uncovertebral involvement in cervical spondylosis. Clin Orthop Relat Res. 1997(334): 200–206.
- Ebraheim NA, Lu J, Brown JA, et al. Vulnerability of vertebral artery in anterolateral decompression for cervical spondylosis. Clin Orthop Relat Res. 1996(322): 146–151.
- Kotani Y, McNulty PS, Abumi K, et al. The role of anteromedial foraminotomy and the uncovertebral joints in the stability of the cervical spine. A biomechanical study. Spine. 1998; 23(14): 1559–1565.
- Lee JY, Löhr M, Impekoven P, et al. Small keyhole transuncal foraminotomy for unilateral cervical radiculopathy. Acta Neurochir. 2006; 148(9): 951–958.
- Lu J, Ebraheim NA, Yang H, et al. Cervical uncinate process: an anatomic study for anterior decompression of the cervical spine. Surg Radiol Anat. 1998; 20(4): 249–252.
- Lyon E. Uncovertebral osteophytes and osteochondrosis of the cervical spine. J Bone Joint Surg Am. 1945; 27: 248–253.
- Milne N. The role of zygapophysial joint orientation and uncinate processes in controlling motion in the cervical spine. J Anat. 1991; 178: 189–201.
- Nourbakhsh A, Yang J, Gallagher S, et al. A safe approach to explore/identify the V(2) segment of the vertebral artery during anterior approaches to cervical spine and/or arterial repairs: anatomical study. J Neurosurg Spine. 2010; 12(1): 25–32.
- Oh SH, Perin NI, Cooper PR. Quantitative three-dimensional anatomy of the subaxial cervical spine: implication for anterior spinal surgery. Neurosurgery. 1996; 38(6): 1139–1144.
- Pait TG, Killefer JA, Arnautovic KI. Surgical anatomy of the anterior cervical spine: the disc space, vertebral artery, and associated bony structures. Neurosurgery. 1996; 39(4): 769–776.
- Panjabi MM, Duranceau J, Goel V, et al. Cervical human vertebrae. Quantitative three-dimensional anatomy of the middle and lower regions. Spine. 1991; 16(8): 861–869.
- Pesch HJ, Bischoff W, Becker T, et al. On the pathogenesis of spondylosis deformans and arthrosis uncovertebralis: comparative form-analytical radiological and statistical studies on lumbar and cervical vertebral bodies. Arch Orthop Trauma Surg. 1984; 103(3): 201–211.
- Raynor RB. Anterior or posterior approach to the cervical spine: An anatomical and radiographic evaluation and comparison. Neurosurgery. 1983; 12: 7–13.
- Russo VM, Graziano F, Peris-Celda M, et al. The V(2) segment of the vertebral artery: anatomical considerations and surgical implications. J Neurosurg Spine. 2011; 15(6): 610–619.
- Saringer WF, Reddy B, Nöbauer-Huhmann I, et al. Endoscopic anterior cervical foraminotomy for unilateral radiculopathy: anatomical morphometric analysis and preliminary clinical experience. J Neurosurg. 2003; 98(2 Suppl): 171–180.
- Shen FH, Samartzis D, Khanna N, et al. Comparison of clinical and radiographic outcome in instrumented anterior cervical discectomy and fusion with or without direct uncovertebral joint decompression. Spine J. 2004; 4(6): 629–635.
- Silberstein CE. The evolution of degenerative changes in the cervical spine and an investigation into the "joints of luschka". Clin Orthop Relat Res. 1965; 40: 184–204.
- Snyder JT, Tzermiadianos MN, Ghanayem AJ, et al. Effect of uncovertebral joint excision on the motion response of the cervical spine after total disc replacement. Spine. 2007; 32(26): 2965–2969.
- Tanaka N, Fujimoto Y, An HS, et al. The anatomic relation among the nerve roots, intervertebral foramina, and intervertebral discs of the cervical spine. Spine (Phila Pa 1976). 2000; 25(3): 286–291.
- Taylor J, Twomey L, Levander B. Contrasts between cervical and lumbar motion segments. Crit Rev Phys Rehabil Med. 2000; 12: 345–371.
- Tubbs RS, Rompala OJ, Verma K, et al. Analysis of the uncinate processes of the cervical spine: an anatomical study. J Neurosurg Spine. 2012; 16(4): 402–407.
- Tulsi RS, Perrett LV. The anatomy and radiology of the cervical vertebrae and the tortuous vertebral artery. Aust Radiol. 1975; 19(3): 258–264.
- Uğur HC, Uz A, Attar A, et al. Anatomical projection of the cervical uncinate process in ventral, ventrolateral, and posterior decompressive surgery. J Neurosurg. 2000; 93(2 Suppl): 248–251.
- Yilmazlar S, Ikiz I, Kocaeli H, et al. Details of fibroligamentous structures in the cervical unco-vertebral region: an obscure corner. Surg Radiol Anat. 2003; 25(1): 50–53.
- Yilmazlar S, Kocaeli H, Uz A, et al. Clinical importance of ligamentous and osseous structures in the cervical uncovertebral foraminal region. Clin Anat. 2003; 16(5): 404–410.
