faces [218] (Case Study 3). Current indications and contraindications for TDA include [11] ( Table 7): Table 7. Indications and contraindications for TDA Indications Contraindications symptomatic cervical disc disease one- or two-level involvement (C3–T1) structural correlate (i.e. herniated nucleus pulposus, cervical spondylosis) failed conservative therapy of 6 weeks age between 20 and 70 years no contraindications three vertebral levels requiring treatment cervical instability (translation >3 mm and/or > 11° angulational differ- ence) cervical fusion adjacent to the target level previous surgery/fracture at target level known allergy to implant materials severe spondylosis (bridging osteophytes, disc height loss > 50 %, and absence of motion <2°, facet joint OA) axial neck pain as the solitary presenting symptom systemic and metabolic diseases (AIDS, HIV, hepatitis B or C, insulin- dependent diabetes, infections, obesity, BMI> 40) Outcome of TDA is not superior to conventional ACDF techniques Preliminary outcome data demonstrated that TDA preserves segmental motion [50, 185] in the short term and compares very favorably to ACDFin terms of clin- ical outcome [23, 179, 184, 243].However,no convincing data wasprovided so far that TDA will prevent adjacent segment degeneration [243]. Posterior Laminectomy Cervical laminectomy was first performed by Sir Victor Horsley (1857–1916) for the treatment of tumor related myelopathy [265]. Laminectomy is a versatile and technically facile approach to decompress the spinal cord [171]. Indications for laminectomy are mainly for the management of: multilevel cervical myelopathy predominant posterior neural compression elderly CSM patients with comorbidities CSM with preserved cervical lordosis Laminectomy provides favorable results in selected cases In elderly patients suffering from significant comorbidities and CSM due to mul- tilevel spinal cord compression, laminectomy is a short and effective procedure to arrest or improve neurological deficits. In the presence of kyphosis, however, laminectomy only has a limited effect since the spinal cord cannot migrate poste- riorly and move away from osteophytes or discs compressing the spine anteri- orly. Good to excellent results have been reported in 56–85% of patients after laminectomy [171]. The lateral extension of laminectomy should not include more than 50% of the facet joint. The resection greater than 50% compromises joint strength significantly and can lead to segmental instability and kyphosis. In multilevel laminectomy, even 25% resection of the facet can reduce cervical sta- bility considerably and require fusion [189]. Laminectomy and Instrumented Fusion Instrumented fusion prevents postoperative deformity and instability The main drawbacks of laminectomies are progressive postoperative deformity and instability, which may subsequently lead to neurological deterioration [109, 135, 257, 299]. These limitations can be overcome by additional instrumented fusion. Most commonly lateral mass screw fixation is used allowing for a good biomechanical stability of the decompressed segments and a high rate of solid fusion [71, 121]. The technique of screw insertion is reviewed in Chapter 13 . With proper technique the risk of complications (vertebral artery or nerve root Degenerative Disorders of the Cervical Spine Chapter 17 457 injury) is minimal [71, 79, 121]. Pedicle cervical screw fixation (see Chapter 13 ) is an alternative but is rarely needed in degenerative disorders with good bone quality [1, 2]. For cases in which correction of a kyphotic deformity is attempted, pedicle screw fixation is advisable for better bony purchase [3]. Posterior Foraminotomy Posterior foraminotomy remains a valid treatment alternative for CSR A posterior foraminotomy for the treatment of cervical nerve root compression was first described by Frykholm [88] ( Fig. 7) and subsequently by Scoville [249] and Murphey [182]. Despite favorable results [122, 305], this approach fell out of favor because of the limitations of treating anterior neural compression of ab cd Figure 7. Technique of posterior foraminotomy (Frykholm) The spine is exposed by a unilateral posterior approach. Tubular retractors allow collateral damage to the neck muscles to be minimized. a A high-speed diamond burr is used to create a keyhole laminotomy exposing the exiting nerve root. b After resection of the ligamentum flavum, epidural veins may become visible which may require coagulation (low- energy bipolar). c The exiting nerve root can gently be lifted cranially to expose the underlying pathology (disc hernia- tion, spur). d The disc herniation or spur can be removed with a rongeur or curette. 458 Section Degenerative Disorders median pathology. Many surgeons therefore prefer the anterior approach with discectomy and osteophytectomy in conjunction with interbody fusion. How- ever, posterior foraminotomy remains a valid option in cases with CSR predom- inantly caused by lateral recess stenosis and lateral disc herniations [159, 161]. The muscles of the neck are rich in proprioceptors that send afferents directly to the vestibular and optical neurons controlling head position on the trunk [148, 213]. This can be the major cause of postoperative persistent neck pain. Access technology makes the posterior approach appealing Recently, minimally invasive procedures were introduced to minimize the trauma to the neck muscles avoiding detachment of the extensor cervical mus- cles from the lamina and spinous process [82]. Burke and Caputy [43] reported on a microendoscopic technique through a transmuscular access with only sep- aration and dilatation of the muscles. Boehm et al. [30] used a working channel of an outer diameter of 11 mm to expose the interlaminar-facet region and reported favorable results with this technique. Clarke et al. [59] have shown that posterior foraminotomy is associated with a low rate of same- and adjacent-seg- ment disease. Laminoplasty The potential destabilization, sagittal malalignment (kyphosis) and the lack of spinal cord protection subsequent to multilevel cervical laminectomy led Japa- nese surgeons to develop cervical laminoplasty techniques [127]. Accordingly, the general advantages of laminoplasty are to [297]: expand the spinal canal secure spinal cord protection maintain spinal stability preserve spinal mobility decrease the risk of adjacent segment degeneration Laminoplasty has predominantly been developed to treat OPLL Hirabayashi introduced a new surgical technique called “expansive open-door laminoplasty” which is still widely used today [126–128]. As an alternative, the “French open-door laminoplasty” was introduced by Hoshi and Kurokawa [129]. Although numerous surgical modifications [117, 137, 147, 165, 174] have been suggested, the basic concept of most of the procedures is similar to one of these two techniques ( Fig. 8). The benefits of laminoplasty are not well supported A recent critical review concluded that the literature has yet to support the purported benefits of laminoplasty [225]. Ratcliff and Cooper [225] concluded that neurological outcome and change in spinal alignment appear to be similar after laminectomy and laminoplasty. Patients treated with laminoplasty appear to develop progressive limitation of cervical range of motion (ROM) similar to that seen after laminectomy and fusion. However, data is lacking on the role of laminoplasty in young individuals with cervical myelopathy due to a congenitally narrow spinal canal and where multilevel decompression and instrumented fusion is not a favorable alternative. Surgical Decision-Making When considering surgery to treat degenerative cervical disorders, the surgical strategy must be based on patient as well as morphological factors ( Table 8). The fundamental question remains “when to operate and when not to” Radiographic alterations are common in asymptomatic patients [29]. The most important factor in patient selection therefore is that clinical and morpho- logical findings must match to obtain a satisfactory outcome. Innumerable arti- cles cover the outcome of surgical treatment for degenerative cervical disorders. Almost all articles cover technical aspects, and safety and early clinical results Degenerative Disorders of the Cervical Spine Chapter 17 459 a b cd Figure 8. Laminoplasty techniques a Expansive open-door laminoplasty according to Hirabayashi [127]. The opened lamina is fixed with a suture through the inferior articular process. b Hemilateral open-door laminoplasty with interposition of a bone graft and fixation according to Itoh [137]. c Alternative fixation with an AO small fragment reconstruction plate. d French open-door lami- noplasty according to Hoshi and Kurokawa [129]. Intraspinous insertion of a bone block and fixation with a suture or cer- clage wire. Table 8. Decision factors for surgical strategy Clinical factors Morphological factors predominant symptoms (neck pain vs. arm pain) presence of neural compression presence of radicular symptoms extent and localization of neural compression presence of myelopathic symptoms soft vs. hard compression severity and duration of symptoms segmental instability onset of symptoms (acute, insidious) spinal deformity (kyphosis) age number of levels involved general patient condition spinal canal width comorbidities spinal cord MR signal changes 460 Section Degenerative Disorders without adequate control groups. Many of the anecdotal studies incorporated a whole variety of indications, which limits conclusions on degenerative cervical disorders. However, when the scientific literature is reduced to Level A recom- mendations (i.e. consistent evidence in multiple high-quality RCTs, Level I evi- dence), only very few RCTs can be identified. The fundamental question regard- ing treatment option is always related to the choice between surgery and non- operative care. However, the literature is equally sparse on such comparisons. These findings greatly limit treatment recommendations. In this section, we therefore try to provide as best evidence-enhanced rather than evidence-based treatment recommendations and the reader should acknowledge this limita- tion. Neck Pain Scientific evidence for the effectiveness of neck pain surgery is poor Axial neck pain is multifactorial and often lacking a structural correlate which can be treated by surgery. Therefore, surgery for neck pain is rarely indicated [15, 223, 291]. However, a certain subset ofthese patients present with atypical radicular pain particularly when upper nerve roots are involved and may benefit from surgery. In this setting, compression of the C4 nerve root has been recognized as a source of neck pain which was successfully treated by surgery [139]. In patients with severe, disabling neck pain who failed an adequate trial of conservative care, the indication for surgery can be explored by using detailed imaging and injection studies [223]. However, the identification of the pain source and painful levels (e.g. by discography or facet joint blocks) remains chal- lenging and often unreliable [64, 107, 150, 200, 256]. Treatment of axial neck pain by fusion is only supported by a few cohort studies [65, 92, 138, 200, 224, 290, 307]. Of note, neck pain alone as the presenting symptom is listed as one of the current contraindications for TDA [11]. Rarely, patients present with severe osteoarthritis at the craniocervical junc- tion ( Fig. 2d), which may necessitate fusion. In selected cases, fusion can result in a significant improvement [284]. Cervical Radiculopathy Conservative care compares favorably to surgery for CSR Only one study so far systematically compared non-operative treatment and sur- gery for radiculopathy [86]. In the prospective study by Persson et al. [211, 212], 81 patients were included who presented with cervicobrachial pain of at least 3 months duration due to spondylotic encroachment with or without an addi- tional bulging disc. The patients were divided into three treatment arms, i.e. sur- gery (Cloward technique), individually adapted physiotherapy or cervical collar. Pain intensity, muscle weakness and sensory loss can be expected to improve within a few months after surgery. Although a short-term benefit for the surgi- cally treated patients was noted, there was no difference in visual analogue scale, Sickness Impact Profile, and Mood Adjective Check List measurements among the groups at 1 year follow-up. The authors concluded that cervical collar, physio- therapy, or surgery are equally effective in the treatment of patients with long- lasting cervical radicular pain. ACDF remains the gold standard for treatment of CSR In some patients, however, radicular symptoms are so severe or persistent despite non-operative care that they opt for a surgical solution. Regarding the cur- rent literature, ACDF still remains the gold standard for surgical treatment [45]. Thereisnoevidencethatadditional anterior plate fixation influences clinical outcome for one-level disease [105, 244, 309] and limited evidence that anterior plating increases the fusion rate for two-level disease [47, 94, 146, 280, 281]. The Degenerative Disorders of the Cervical Spine Chapter 17 461 Cage fusion and TDA are superior to ACDF only regarding donor site pain evidence for the superiority of cage fusions [111, 210, 233, 273] or TDA [23, 179, 184, 243] compared to ACDF is lacking except in terms of iliac crest donor site pain. Particularly, the superiority of TDA in terms of adjacent segment degenera- tion studies remains unproven. Minimally invasive decompressions (anterior or posterior) for the treatment of selected radiculopathy patients [30, 43, 140, 240, 241] remain intriguing becausetheypreservesegmentalmotionanddonotrequireinstrumentation (potential cost-effectiveness). But, so far, scientific evidence is lacking for their role in the treatment of cervical radiculopathy. Treatment outcome is primarily dependent on nerve root decompression In general, the treatment outcome of surgical treatment of cervical radiculo- pathy is favorable with good to excellent results in 83–97% [33, 96, 102, 110] and primarily dependent on the nerve root decompression and not so much on the specific surgical technique. Cervical Spondylotic Myelopathy There is no evidence against surgery in moderate to severe CSM cases It is not known whether surgery results in better results than conservative care in mild to moderate CSM [142]. In a prospective study, Kadanka et al. [142] ran- domized48patientswithmildtomoderateCSMintoaconservativeandanoper- ative arm. There wasno significant deterioration inmodified JOA score, recovery ratio, or timed 10-m walk within either group during the 2 years of follow-up. The authors concluded that surgical treatment of mild and moderate forms of CSM, consisting of patients with no or very slow, insidious progression and a rel- atively long duration of symptoms, was not superior to conservative care [142]. However, there is no controversy as to whether severe or progressive CSM should be treated by decompression [22, 223]. The goal of surgery is to completely decompress the spinal cord The primary surgical object ive in CSM is the arrest or improvement of neuro- logical deficits by spinal cord decompression. In a prospective, multicenter non- randomized study, surgically treated patients had a significant improvement in functional status and overall pain, with improvement also observed in neurolog- ical symptoms [239]. Conservatively treated patients had a significant worsening of their ability to perform activities of daily living, with worsening of neurologi- cal symptoms [239]. A meta-analysis of more than 2000 patients treated by lami- noplasty revealed a mean improvement rate of 80% [225]. The choice of the surgical technique is dependent on the target pathology and patient characteristics The decompression of the spinal cord canbeachievedeitherby: anterior approach (multilevel ACDF or corpectomy ± plate fixation) posterior approach (laminoplasty, laminectomy ± instrumented fusion) combined anterior/posterior approach Corpectomy and anteropo- sterior instrumented fusion results in a reliable outcome Although innumerable studies have been reported for each of these approaches, the scientific evidence for treatment recommendations remains limited. Only a few studies have provided some evidence which is helpful for surgical decision- making. There is moderate evidence that multilevel ACDFs are associated with a high non-union rate [33, 49, 78] and limited evidence that corpectomies result in a lower non-union rate for multilevel decompression [263]. In three and more level ACDFs or corpectomies, anterior plate fixation does not suffice [136, 242, 270, 281] and additional posterior fixation is recommended [73, 93, 162, 226]. There is limited evidence that both multilevel corpectomy and laminoplasty are equally effective in arresting myelopathic progression in multilevel cervical mye- lopathy and can lead to significant neurological recovery and pain reduction in a majority of patients [72]. The neurological recovery appears not to be dependent on the laminoplasty technique [225]. However, there is limited evidence that patients treated with laminoplasty develop progressive limitation of cervical ROM similar to that seen after laminectomy and fusion [225]. 462 Section Degenerative Disorders Factors Affecting Outcome Spinal canal dimensions and signal intensity changes predict outcome The outcome of surgery appears to be critically dependent on the extent of the spinal canal stenosis and cord compression. Yamazaki et al. [294] analyzed the prognostic factors by comparing younger and elderly patient groups on the basis of preoperative radiological and clinical data. The authors found that for elderly patients, the transverse area of the spinal cord at the level of maximum compres- sion and symptom duration were the factors that predicted an excellent recovery. In younger patients, the transverse area was the only predictor of excellent recov- ery. Age, preoperative JOA score, canal diameter, and an intensity change on the spinal cord were not predictive in either age range [294]. Fujiwara et al. [89] showed that the transverse cord area at the site of maximum compression corre- lates significantly with the results of surgery. In most patients with less than 30 mm 2 of spinal cord area, the results are poor. Patients with high intramedul- lary signal change on T2W images who do not have clonus or spasticity may experience a good surgical outcome and may have reversal of the MRI abnormal- ity [6]. A less favorable surgical outcome is predicted by the presence of low intra- medullary signal on T1W images, clonus, or spasticity [6]. Based on these find- ings, Alafifiet et al. [6] suggested that there may be a window of opportunity for obtaining optimal surgical outcomes in patients with CSM. Yonenobu [297] has indicated that surgery performed too late in a stage with already severe myelopa- thy generally had a poor prognosis and therefore advocates early surgery. Staged combined anterior/ posterior decompression for myelopathy is safer Some debate continues on the question of whether combined anterior/poste- rior surgery to decompress moderate to severe myelopathy should be done staged or in one surgery [180].Thereisnoevidencetosupportoneapproach over the other. Anecdotally, we have seen patients admitted to our spinal cord injury unit who experience substantial neurological deterioration after com- bined surgery. We therefore recommend performing anterior/posterior spinal cord decompression staged in moderate to severe myelopathy cases to minimize edema and allow blood supply to the spinal cord to readapt between the surger- ies. Complications A comprehensive review of complications is provided in Chapter 39 . In general, complications of surgery for CSR and CSM are uncommon but can include [45, 85, 306]: cerebrospinal fluid leak (0.2–0.5%) recurrent laryngeal nerve injury (0.8–3.1%) dysphagia (0.02–9.5%) Horner’s syndrome (0.02–1.1) cervical nerve root injury (0.2–3.3%) hematoma (0.2–5.6%) tetraparesis (0.4%) death (0.1–0.8%) infection (0.1–1.4%) esophageal perforations (0.2–0.3%) non-union (dependent on technique) graft dislodgement/collapse (dependent on technique) instrumentation failure (dependent on technique) Dysphagia is a common postoperative complication Dysphagia isa quite frequent symptom after anterior cervical surgery and can be encountered in up to 50% of cases in the immediate postoperative period [17]. Dysphagia is dependent on the number of levels treated [227]. At 12 months post- Degenerative Disorders of the Cervical Spine Chapter 17 463 operatively, however, the rate of moderate to severe dysphagia decreases to about 13% [17]. The etiology of this complication is not fully understood. An injury to the superior laryngeal nerve has been suggested as a potential cause [131]. Papa- vero et al. [202] have reported that no correlation exists between the pharynx/ esophagus retraction and postoperative swallowing disturbances. RLN injury is not dependent on the approach site Recurrent lar yngeal nerve (RLN) palsy has been reported in 2–11% [223]. In contrast to common belief, the injury rate does not appear to be related to the side of the approach [26]. Postoperative laryngoscopy revealed that the true inci- dence of initial and persisting RLN palsy after anterior cervical spine surgery was much higher than anticipated [141]. Jung et al. [141] reported that the postopera- tive rate of clinically symptomatic RLN palsy was 8.3%, and the incidence of RLN palsy not associated with hoarseness (i.e. clinically unapparent without laryn- goscopy) was 15.9%. At 3 months postoperatively, these rates decrease to 2.5% and 10.8%, respectively [141]. C5 radiculopathy is a serious complication of spinal cord decompression An infrequent but serious complication is a postoperative C5 palsy which can develop in up to 3–5% of patients after posterior decompression surgery partic- ularly laminoplasty [133, 235]. It has been suggested that this neural compromise is a result of traction on the short C5 nerve root due to posterior migration of the cord after posterior decompression [223]. However, a systematic review did not reveal significant differences between patients undergoing anterior decompres- sion and fusion and laminoplasty, nor were distinctions apparent between uni- lateral hinge laminoplasty and French-door laminoplasty, or between cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament [235]. The pathogenesis of postoperative C5 palsy remains unclear at the present time. Patients with postoperative C5 palsy generally have a good prognosis for functional recovery, but the severely paralyzed cases required significantly lon- ger recovery times than the mild cases [235]. Recapitulation Epidemiology. Degenerative changes of the cervi- cal spine (cervical spondylosis) can result in cervical disc herniation with radiculopathy, cervical spondy- lotic radiculopathy (CSR) and myelopathy (CSM). Degenerative cervical spondylosis is very common in the aging population but not necessarily associ- ated with symptoms. The prevalence of neck pain ranges between 17 % and 34% in a general popula- tion. More than half of the adult population suffer from cervical radiculopathy (CR) at least once in their lifetime. The C6 and C7 nerve roots are most frequently affected. Cervical spondylosis more fre- quently causes CR than disc herniation (3:1). Cervi- cal spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction in indi- viduals older than 55 years. A special form of cervi- cal myelopathy is caused by an ossification of the posterior longitudinal ligament (OPLL) and is com- monintheAsianpopulation. Pathogenesis. Predominant neck pain can arise from painful degeneration of the motion segment and can be attributed to disc degeneration, facet joint osteoarthritis and segmental instability. In the vast majority of cases with subaxial neck pain the correlation of morphological alterations and neck pain remains weak (non-specific neck pain). Radi- culopathy due to disc herniation (so-called soft her- niations) usually occurs during early stages of disc degeneration in the 4th–5th life decades. Compres- sive spondylotic spurs usually develop during later degenerative stages (so-called hard herniations). Both mechanical and inflammatory processes cause the clinical syndrome of radiculopathy. CSM is mainly due to a compression of the spinal cord by osteophy- tes, calcified disc herniations, yellow ligament hyper- trophy or OPLL. Mechanical compression and vascu- lar insufficiency lead to pathobiologic alterations re- sulting in myelopathy. The clinical manifestation of CSM depends on the degree of cord compression and time course of compression. The major risk fac- tor is a congenitally narrow spinal canal (sagittal di- ameter < 13 mm). Minor trauma can acutely increase the compression which the spinal cord cannot toler- 464 Section Degenerative Disorders ate any more, leading to sudden severe neurologi- cal deficits. Dynamic compression can aggravate spinal cord compression. Flexion lengthens the spi- nal cord and extension leads to a buckling of the ligamentum flavum which results in a bilateral cord compression (pincer effect). In addition to mechan- ical compression, vascular factors play a significant role in the development of myelopathy. Ischemia and a cascade of cellular and molecular events (glutamatergic toxicity, free radical cell injuries, and apoptosis) aggravate the compromise of the spinal cord. The causes of the OPLL are not well explored but gene polymorphisms appear to play an essen- tial role. Clinical presentation. The clinical assessment aims to differentiate between patients with specific and non-specific cervical disorders. Patients quite fre- quently present with pain syndrome located in the neck-shoulder-arm region. Neck pain most fre- quently is non-specific (i.e. without a clear structural correlate) but can seldomly be part of a so-called spondylotic syndrome (i.e. painful motion segment degeneration). The cardinal symptoms of cervical radiculopathy are a predominant radicular arm pain with or without sensorimotor and reflex deficits. Accompanying vegetative symptoms, dizziness, vertigo and headaches are not uncommon. A thor- ough neurological examination and nerve root provocation tests (e.g. Spurling test) are helpful in diagnosing radiculopathy. Radiculopathy can be associated with myelopathy because cervical spon- dylosis not only affects the foramen but also the spi- nal canal. A myelopathic syndrome can begin very subtly and can therefore pose a diagnostic chal- lenge. Patients with cervical myelopathy can pre- sent with a broad spectrum of signs and symptoms depending on the magnitude of spinal cord dys- function and chronicity. The leading symptoms are numb, clumsy, painful hands and compromised fine motor skills. Further findings are atrophy of the interosseous muscles, gait disturbances, ataxia, and symptoms of progressive tetraparesis. Diagnostic work-up. Morphological alterations in imaging studies are frequent in asymptomatic con- trols, jeopardizing their role in identifying the pain source. Standard radiographs (anteroposterior, lat- eral, oblique views) of the cervical spine may give important information about spinal alignment, spi- nal curvature, disc space narrowing, spondylophytes, facet joint osteoarthritis, foraminal stenosis, develop- mental anomalies, and DISH. Functional radio- graphs have failed to reliably allow the diagnosis of segmental instability. Therefore, instability remains a clinical diagnosis. The imaging modality of choice is MRI. Sagittal T2W images tend to overestimate the spinal cord compression, favoring T1W images for this assessment. MR signal intensity changes repre- sent structural alterations of the spinal cord and have some prognostic value for treatment outcome. CT myelography provides better information than MRI regarding the relationship between neural compres- sion by osteophytes or ossifications. Injection stud- ies (facet joint blocks, discography) do not reliably allow identification of the pain source. Neurophysio- logical studies are helpful in differentiating radiculo- pathy and peripheral neuropathy. Furthermore, they allow the recognition of subclinical myelopathy. Non-operative treatment. Most cases of non-spe- cific acute neck pain resolve within a few days or weeks. But neck pain frequently recurs and can become disabling in about 6% of cases. The natural history of CSR generally is benign. However, CSR has a somewhat worse course than disc related radiculopathy because disc extrusion/sequestra- tions tend to regress with time while osseous com- pression tends to increase. The natural history of CSM has a variable clinical course which is charac- terized either by long periods of stable disability followed by episodes of deterioration or a linear progressive course. In advanced stages, complete remission to normality never occurs. Non-specific neck pain and spondylosis related neck pain are best managed with conservative care because a clear morphological correlate which could be addressed by surgery is often missing. In the absence of major (MRC Grade >3) or progressive motor deficits, CSR should be treated with an initial trial of non-operative care. Persistence of severe pain and sensorimotor deficits despite adequate non-operative care should prompt the indication for surgery in cases with a clear morphological cor- relate. Non-surgical treatment is only indicated in mild forms of CSM. In cases with circumferential spinal cord compression, deterioration under con- servativecaremustbeexpected.Themainstay of non-surgical care consists of oral medications (e.g. analgesics, NSAIDs, muscle relaxants, psychotropic drugs), manipulative treatment, and physical exer- cises. There is moderate evidence that spinal manipulative therapy (SMT) and mobilization is superior to general practitioner management for Degenerative Disorders of the Cervical Spine Chapter 17 465 short-term pain reduction of chronic neck pain. There is limited evidence for the effectiveness of spinal injections, which are more dangerous than previously thought. Radiofrequency denervation of facet joints is only supported by limited evidence. There is no evidence for the effectiveness of mas- sage, acupuncture, or electrotherapy. Operative treatment. In general, patients with pro- gressive neurological symptoms and those failing to respond to non-operative treatment should be considered candidates for surgery. Axial neck pain is multifactorial and often lacking a structural corre- late which can be treated by surgery. Therefore, sur- gery for neck pain is rarely indicated.Anteriorcer- vical discectomy and fusion (ACDF) still remains the gold standard for surgical treatment of CR.Thereis no evidence that additional anterior plate fixation influences clinical outcome for one-level disease and only limited evidence for the increase of the fusion rate for two-level disease. Similarly, there is no evidence for the superiority of cage fusions or total disc arthroplasty (TDA) compared to ACDF with the exception of iliac crest donor site pain. Minimally invasive decompressions (anterior or posterior) for the treatment of selected radiculopa- thy patients remain intriguing because they pre- serve segmental motion and do not require instru- mentation. The outcome of surgery for CR is largely dependent on the successful decompression of the nerve root(s) and not per se on the chosen surgical technique. The primary surgical objective in CSM is to arrest or improve neurological deficits by spi- nal cord decompression, which is possible in about 80% of patients depending on the disease state. Spinal decompression can be achieved by (multi- level) ACDF, corpectomy, laminectomy or lamino- plasty. The surgical techniques must be tailored to the target pathology. There is moderate evidence that multilevel ACDFs are associated with a high non-union rate and limited evidence that corporec- tomies result in a lower non-union rate for multi- level decompression. In three and more level ACDFs or corpectomies, anterior plate fixation does not suffice and additional posterior fixation is recommended. There is limited evidence that both multilevel corpectomy and laminoplasty are equally effective in arresting myelopathic progres- sion in multilevel cervical myelopathy. Patients treated with laminoplasty develop progressive lim- itation of cervical ROM similar to that seen after laminectomy and fusion. The neurological recovery appears not to be dependent on the decompres- sion technique but spinal canal dimensions and MR signal intensity changes of the spinal cord are strong predictors of surgical outcome. Dysphagia is a quite frequent symptom after anterior cervical surgery and can be encountered in up to 50% of cases in the immediate postoperative period. How- ever, most patients (90%) recover within 1 year after surgery. Recurrent laryngeal nerve (RLN) injury is reported in 2–11 % and independently of the approach site. An infrequent but serious com- plication is a postoperative C5 palsy which can developinupto3–5%ofpatientsafterposterior decompression surgery, particularly laminoplasty. Key Articles Baptiste D C , Fehlings MG (2006) Pathophysiology of cervical myelopathy. Spine J 6(6 Suppl):190S–197S Excellent review of the current knowledge of the pathophysiology of cervical myelo- pathy. Gross AR, Goldsmith C, Hoving JL, Haines T, Peloso P, Aker P, Santaguida P, Myers C (2007) Conservative management of mechanical neck disorders: a systematic review. JRheumatol34:1083 – 102 This comprehensive review noted strong evidence for the benefit of exercise plus mobili- zation/manipulation in the treatment of subacute/chronic mechanical neck pain. There was moderate evidence for the long-term benefit of direct neck strengthening and stretching exercises for chronic neck pain. Many other treatments only demonstrated short-term effects. Persson LC, Carlsson CA, Carlsson JY (1997) Long-lasting cervical radicular pain man- aged with surgery, physiotherapy, or a cervical collar. A prospective, randomized study. Spine 22:751 – 8 466 Section Degenerative Disorders . presence of neural compression presence of radicular symptoms extent and localization of neural compression presence of myelopathic symptoms soft vs. hard compression severity and duration of symptoms. general advantages of laminoplasty are to [297]: expand the spinal canal secure spinal cord protection maintain spinal stability preserve spinal mobility decrease the risk of adjacent segment. their role in the treatment of cervical radiculopathy. Treatment outcome is primarily dependent on nerve root decompression In general, the treatment outcome of surgical treatment of cervical radiculo- pathy