The author describes the fundamentals in diagnosis and treatment of cervical disc disease. A historical overview is provided as well as some of the newest concepts in diagnostic imaging and surgical repair. Case studies with imaging and intraoperative photographs are reviewed.
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• Neck pain, with or without radiating arm pain and associated root distribution paraesthesias, numbness, and motor deficit, is the classic presenting feature of cervical disc disease.
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• Degenerative changes in the cervical disc are an inevitable result of aging, and rupture of disc material through the annulus frequently presents as an irritative mass against the centrally positioned spinal cord or laterally positioned root.
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• Along with historical features, physical exam findings help to establish the diagnosis of cervical disc rupture and to distinguish between other causes of pain in the upper extremity, such as shoulder impingement or myofascial pain syndromes.
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• Cervical MRI has become the standard imaging test to confirm the diagnosis of cervical disc disease and rupture; other diagnostic tools such as EMG, CT, or CT-myelography and motion (flexion-extension) x-rays assist in confirmation of diagnosis and in treatment planning.
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• Conservative, nonsurgical treatment is effective and recommended for the majority of cervical disc ruptures, and includes nonsteroidal anti-inflammatory medications, analgesics and muscle relaxants, physical therapy, and traction, as well as epidural steroid injections in selected cases.
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• Surgical treatment consists of nerve or spinal cord decompression, with or without fusion of the disc space segment; there are various time-honored approaches as well as newer techniques and advances, including artificial disc replacement (disc arthroplasty).
Historical note and terminology
Neck pain, with or without neurologic signs or symptoms, is virtually ubiquitous in modern adult society and represents 1 of the more common reasons for missed work or visits to the general practitioner, physical therapist, chiropractor, orthopedist, neurologist, or neurosurgeon. Pathological changes in the intervertebral disc and their presumed relationship to neck pain were not well described until the 19th century by such pioneers as Key, Gowers, and von Bechterew (122), and surgical treatment was not attempted until Sir Victor Horsley performed a posterior cervical decompression for spondylotic myelopathy in 1892 (114). Osteoarthritic compression syndromes of the cervical cord and roots were increasingly reported by the turn of the 20th century (07); in 1928, Stookey described a surgical treatment for "ventral extradural cervical chondroma" (109). Walter Dandy recognized the "chondroma" removed from a patient's lumbar spinal canal as displaced cartilaginous disc material (27), and in the 1934 landmark report of surgical treatment for ruptured intervertebral disc, Mixter and Barr described 4 cervical cases among a larger group of lumbar disc ruptures (78). Gradually the characteristic "soft disc" and "hard disc" compression syndromes were recognized and distinguished from other ailments involving the cervical roots and cord, such as amyotrophic lateral sclerosis, the spastic paraparesis of pernicious anemia ("combined-system disease"), brachial neuralgia or neuritis, and scalenus anticus or thoracic outlet syndrome (30). Spurling further classified the various cervical root compression syndromes and popularized the posterior surgical approach (107; 108), and Lord Brain provided a definitive patient assessment for eliciting history and signs of cervical myelopathy, radiculopathy, and myeloradiculopathy (13). The introduction of positive contrast imaging of the spinal cord and nerve roots in 1944, myelography, raised diagnostic confidence and clinical awareness, which has been further enhanced with CT scanning and the advent of noninvasive MRI.
Degenerative changes in the cervical intervertebral disc are an inevitable result of aging and are influenced by major and minor mechanical stresses to the cervical spine. Dehydration of the disc occurs naturally, allowing shrinkage, cracking, and protrusion of nuclear material through weakening support elements, the annulus and posterior longitudinal ligament. Clinically, this process yields a continuum from the "soft disc" rupture in the earlier phase to the "hard disc," "spur," or osteophyte in the later phase, and often both elements are found to some degree in those cases that come to surgery. Nomenclature varies, and (depending on context, degree of protrusion, and imaging findings) cervical disc herniation may be referred to as "annular bulge," "subligamentous rupture," "extradural rupture" or "free fragment rupture." Ideally, the imaging or surgical description of the abnormality should be based on anatomical compartment (annular, subligamentous, extradural), site of compression (central or ventral, centrolateral, foraminal), and tissue quality (soft disc, ridge, or spur). Cervical spondylosis at an isolated site may be referred to as "osteophyte" or "spur," whereas the unmodified term "spondylosis" refers to a more generalized, frequently multilevel condition. Degenerative changes in the disc may be associated with sclerotic changes in the uncovertebral "joint" (joint of Luschka) or uncinate process located just anterior to the intervertebral foramen, further narrowing the root's bony passage, hence the term "uncovertebral spur."