Incidence Of Postoperative C5 Palsy Research Articles

Postoperative C5 Palsy after Anterior or Posterior Decompression for Degenerative Cervical Myelopathy: A Subgroup Analysis of the Multicenter, Prospective, Randomized, Phase III, CSM-Protect Clinical Trial.

Retrospective cohort study of prospectively accrued data. To evaluate a large, prospective, multicentre dataset of surgically treated degenerative cervical myelopathy (DCM) cases on the contemporary risk of C5 palsy with surgical approach. The influence of surgical technique on postoperative C5 palsy after decompression for DCM is intensely debated. Comprehensive, covariate-adjusted analyses are needed using contemporary data. Patients with moderate to severe DCM were prospectively enrolled in the multicenter, randomized, Phase III CSM-Protect clinical trial and underwent either anterior or posterior decompression between Jan 31, 2012 and May 16, 2017. The primary outcome was the incidence of postoperative C5 palsy, defined as the onset of muscle weakness by at least one grade in manual muscle test at the C5 myotome with slight or absent sensory disruption after cervical surgery. Two comparative cohorts were made based on the anterior or posterior surgical approach. Multivariate hierarchical mixed-effects logistic regression was used to estimate odds ratios (OR) with 95% confidence intervals (CI) for C5 palsy. A total of 283 patients were included, and 53.4% underwent posterior decompression. The total incidence of postoperative C5 palsy was 7.4% and was significantly higher in patients who underwent posterior decompression compared with anterior decompression (11.26% vs. 3.03%, P =0.008). After multivariable regression, the posterior approach was independently associated with greater than four times the likelihood of postoperative C5 palsy ( P =0.017). Rates of C5 palsy recovery were comparable between the two surgical approaches. The odds of postoperative C5 palsy are significantly higher after posterior decompression compared to anterior decompression for DCM. This may influence surgical decision-making when there is equipoise in deciding between anterior and posterior treatment options for DCM. Therapeutic Level-II.

Impact of lamina-open side on unilateral open door laminoplasty in patients with degenerative cervical myelopathy

Surgeons should select one side for cervical unilateral open door laminoplasty (UODL). However, few reports suggest proper guidelines for deciding which side to open. The aim of this study is to evaluate the impact of opening side in UODL on dominant cord compressive or symptomatic side. 193 degenerative cervical myeloradiculopathy patients with followed-up more than 2 years were enrolled. In all cases, UODL was performed uniformly on the right side. Patients were sub-grouped based on preoperative dominant 3 characteristics: cord compression, myelopathy symptom and radiculopathy symptom (right, symmetric, left). Pre- and postoperative radiographic and clinical parameters and incidence of postoperative C5 palsy were analyzed and compared among the groups. According to dominant compressive side, there were no significant differences in postoperative radiographic and clinical parameters among three groups. According to dominant myelopathy or radiculopathy symptom side, there were no significant differences of all radiographic and clinical parameters postoperatively, except slightly lower neck VAS in groups of preoperative right dominant myelopathy or radiculopathy symptom side at postoperative 1 month. C5 palsies occurred in twelve patients (6.2%), but the incidences were not different among the groups. Therefore, when performing UODL, the choice of lamina opening side can be left to surgeon’s preference.

Plate Fixation of Expansive Open-Door Laminoplasty Decreases the Incidence of Postoperative C5 Palsy.

Retrospective study. To compare outcomes for plate fixation versus suture suspension in expansive open-door laminoplasty (ELAP) for cervical spondylotic myelopathy (CSM). C5 palsy and laminar closure have been reported to occur after ELAP when suture suspension is used to anchor the opened lamina. We assessed 174 patients with CSM who were treated by ELAP using either suture suspension (114 patients, mean age 63.3 y, 83 men and 31 women, mean follow-up 12.0 mo) or laminoplasty plate (60 patients, mean age 65.6 y, 45 men and 15 women, mean follow-up 12.6 mo) to maintain the position of the opened laminae. We compared clinical outcomes, radiographic findings, and complications between the 2 groups. Mean Japanese Orthopaedic Association scores had improved significantly for both groups at the final follow-up (P<0.001), with similar recovery rates: scores improved from 10.8±2.8 to 13.4±2.8 points in the suture-suspension (SS) group and from 11.3±2.7 to 13.6±2.2 points in the laminoplasty plate (LP) group. The incidence of C5 palsy was significantly higher in the SS group (7.9%) than in the LP group (1.7%; P<0.05). Computed tomography (CT) showed larger mean angles of the opened laminae in the SS group compared with the LP group (P<0.01). Magnetic resonance imaging (MRI) showed that the mean anterior spinal-cord space at the C5 level was larger in the SS group than in the LP group (P<0.01). Plate fixation in ELAP produced comparable clinical outcomes and significantly lowered the incidence of C5 palsy compared with suture suspension. CT and MRI findings indicated that laminoplasty plate fixation prevented excessive opening of the lamina and decreased dorsal spinal-cord shift, which might explain the lower incidence of C5 palsy.

Selective blocking laminoplasty in cervical laminectomy and fusion to prevent postoperative C5 palsy

BACKGROUND CONTEXTCervical laminectomy and fusion (CLF) is a common surgical option for multilevel cord compression. Postoperative C5 palsy occurrence after CLF has been a vexing problem for spine physicians. The posterior shift of the cord following laminectomy has been implicated as a major factor for postoperative C5 palsy, but attempts by spine surgeons to mitigate excessive shift while providing sufficient decompression have not been well reported. PURPOSETo compare the incidence of postoperative C5 palsy after performing selective blocking laminoplasty concurrently with CLF to those of conventional CLF. STUDY DESIGNA retrospective comparative study of prospectively collected data. PATIENT SAMPLEOf 116 cervical myelopathy patients with degenerative cervical myelopathy, ossification of the posterior longitudinal ligament, and multilevel disc herniation, 93 patients (69 in group A [CLF group] and 24 in group B [selective blocking laminoplasty with CLF, CLF-S group]) were included in the study. OUTCOME MEASURESThe primary outcome measure was the occurrence of postoperative C5 palsy. Secondary end points included (1) clinical outcomes based on pain intensity, neck disability index (NDI), Japanese Orthopaedic Association (JOA) score, (2) radiologic outcomes including cervical alignment and fusion rate at 1 year and hardware complications, and (3) perioperative data (hospital stay, blood loss, and operative times). METHODSWe compared the occurrence of postoperative C5 palsy, as well as clinical, radiologic, and surgical outcomes, between the two groups at 1-year follow-up. RESULTSThe patients in both groups were statistically similar between the groups with respect to demographic characteristics such as age, sex, smoking status, body mass index, preoperative pathology, surgical segments, and the degree of the cervical lordosis. Postoperative C5 palsy developed in 9 of 61 patients (14%) in group A and in 0 of 24 patients (0%) in group B (CLF-S group) (p=.03). Postoperative neck pain, NDI, and JOA improvement were not significantly different between the two groups (p=.93, 0.90, and 0.79, respectively). Perioperative data did not differ significantly between the two groups. CONCLUSIONSThis study showed that performing selective blocking laminoplasty might lead to reducing the incidence of postoperative C5 palsy in CLF surgery.

Simple presurgical method of predicting C5 palsy after cervical laminoplasty using C5 nerve root ultrasonography.

The incidence of C5 palsy after cervical laminoplasty is approximately 5%. Because C5 palsy is related to cervical foraminal stenosis at the C4-5 level, the authors hypothesized that cervical foraminal stenosis can be diagnosed by examining the C5 nerve root (NR) using ultrasonography. The purpose of this study was to investigate whether postoperative C5 palsy could be predicted using ultrasonography. This study used a prospective diagnosis design. In total, 140 patients undergoing cervical laminoplasty were examined with ultrasound. The cross-sectional area (CSA) of the C5 NR was measured on both sides before surgery, and the incidence of postoperative C5 palsy was examined. The difference between the CSA of the patients with and without C5 palsy and the lateral differences in the C5 palsy group were determined. The incidence of C5 palsy was 5% (7 cases). Symptoms manifested at a median of 5 days after surgery (range 1-29 days). The CSA of the C5 NR on the affected side was significantly enlarged in the C5 palsy group compared with that in the no-C5 palsy group (p = 0.001). In addition, in the patients who had C5 palsy, the CSA of the C5 NR was significantly enlarged on the affected side compared with that on the unaffected side (p = 0.02). Receiver operating characteristic analysis indicated that the best threshold value for the CSA of the C5 NR was 10.4 mm2, which provided 91% sensitivity and 71% specificity. C5 palsy may be predicted preoperatively using ultrasound. The authors recommend the ultrasonographic measurement of the CSA of the C5 NR prior to cervical laminoplasty.

Paralisia de C5 Pós-Descompressão Medular Cervical

A paralisia de C5 é uma conhecida complicação de cirurgia de descompressão medular cervical devido à mielopatia espondilótica crônica, que pode ser definida como déficit motor do deltóide e/ou do bíceps braquial, déficit sensitivo no território de C5, ou aumento da dor no território de C5 comparado ao status pré-operatório. Apresentamos um relato de caso de um paciente com mielopatia espondilótica cervical que foi submetido à laminectomia dos níveis C4 a C6 e evoluiu com paralisia de C5, obtendo melhora muito significativa em aproximadamente um ano. A incidência de paralisia de C5 pós-operatória pode variar de 0 a 30%, conforme a literatura. A fisiopatologia da paralisia pós-operatória de C5 ainda não é bem compreendida. Os pacientes geralmente têm bom prognóstico. A recuperação é espontânea, o que justifica o emprego de tratamento conservador. Há estudos comparando diferentes técnicas empregadas para descompressão medular cervical quanto à recuperação neurológica e a ocorrência de paralisia pós-operatória de C5, bem como avaliando o valor preditivo de monitoração neurofisiológica.

C5 Palsy in Cervical Decompression Surgeries: A Study in 390 Patients

Introduction C5 palsy following cervical decompression is a known complication. The exact incidence is unclear, due to varying definitions in literature. C5 palsy is associated with significant morbidity due to weakness of deltoid/biceps. Aim To report incidence of postoperative C5 palsy in cervical decompression surgeries for myelopathy and its correlation with demographic factors, etiology, radiological factors, and to assess recovery of palsy. Materials and Methods All patients who underwent cervical decompression surgeries from 2006 to 2015 in a single institute were reviewed. A postoperative decrease by ≥ 1 manual muscle testing grade in only C5 myotome (deltoid/biceps/both) is taken as positive. Demographic, radiological, surgical factors resulting in C5 palsy and time of onset, duration of symptoms, and degree of recovery were noted. Results A total of 390 patients were included in the study. Out of which, 232 patients underwent anterior while 158 had posterior surgeries. In all, 72 patients had ossification of the posterior longitudinal ligament (OPLL) and rest had spondylotic myelopathy. Incidence of palsy was 6.3% and mean onset of palsy was 2.8 days. Mean duration for recovery was 6.3 months with near complete recovery seen in majority of the patients (9/10). No significant relation was noted with age, preoperative Japanese Orthopedic Association score, change in cervical lordosis, and C45 intervertebral angle. Posterior surgeries, laminectomy, C45 foraminal stenosis, and OPLL were seen as risk factors for C5 palsy. Conclusion Cervical decompression surgeries are relatively safe, with a small risk of C5 palsy. Though majority of patients recover with conservative treatment, preoperative counseling of this complication has to be explained.

Hybrid Decompression and Fixation Technique Versus Plated 3-Vertebra Corpectomy for 4-Segment Cervical Myelopathy

A retrospective comparative study. The purpose of this study was to compare the stability and outcomes of a hybrid technique with those of a 3-vertebra corpectomy in the management of 4-segment cervical myelopathy. Patients with primarily ventral disease and loss of cervical lordosis are considered good candidates for anterior surgery. Cervical corpectomy is commonly performed in patients with multilevel cervical myelopathy. Corpectomies including >3 vertebraes entail an extremely high risk of reconstruction failure. To avoid the need to perform a 3-vertebra corpectomy, we use a hybrid decompression and fixation technique. This hybrid technique is a technique to obtain optimum decompression and fixation in patients with multilevel cervical myelopathy. A total of 81 patients with multilevel cervical myelopathy who underwent 4-segment cervical fixation with a minimum 2-year follow-up were included. The hybrid technique involved combining a plated 2-vertebra corpectomy and single-level discectomy with stand-alone cage fixation. This technique was performed in 39 patients, and the plated 3-vertebra corpectomy was performed in 42 patients. Nine patients (21%) who underwent the plated 3-vertebra corpectomy were treated with halo immobilization, but no patient in the hybrid group required this treatment (P=0.002). There were fewer instances of reconstruction failure in the hybrid group than in the 3-vertebra corpectomy group (0% vs. 10%, respectively; P=0.048) and fewer instances of C5 palsy (3% vs. 17%, respectively; P <0.0001). The incidence of postoperative C5 palsy was 25% for C3-C5 corpectomy, 19% for C4-C6 corpectomy, and 11% for C4-C5 corpectomy+C6-C7 discectomy. The hybrid technique has the following advantages over 3-vertebra corpectomy for 4-segment cervical fixation: a shorter graft bone and plate are required; the fixed segment has greater initial stability; postoperative external immobilization is simplified; and the risk of reconstruction failure and postoperative C5 palsy is reduced markedly.

C5 nerve palsy after posterior reconstruction surgery: predictive risk factors of the incidence and critical range of correction for kyphosis.

It has been reported that the incidence of post-operative segmental nerve palsy, such as C5 palsy, is higher in posterior reconstruction surgery than in conventional laminoplasty. Correction of kyphosis may be related to such a complication. The aim of this study was to elucidate the risk factors of the incidence of post-operative C5 palsy, and the critical range of sagittal realignment in posterior instrumentation surgery. Eighty-eight patients (mean age 64.0years) were involved. The types of the disease were; 33 spondylosis with kyphosis, 27 rheumatoid arthritis, 17 athetoid cerebral palsy and 11 others. The patients were divided into two groups; Group P: patients with post-operative C5 palsy, and Group NP: patients without C5 palsy. The correction angle of kyphosis, and pre-operative diameter of C4/5 foramen on CT were evaluated between the two groups. Multivariate logistic regression analysis was used to determine the critical range of realignment and the risk factors affecting the incidence of post-operative C5 palsy. Seventeen (19.3%) of the 88 patients developed C5 palsy. The correction angle of kyphosis in Group P (15.7°) was significantly larger than that in Group NP (4.5°). In Group P, pre-operative diameters of intervertebral foramen at C4/5 (3.2mm) were significantly smaller than those in Group NP (4.1mm). The multivariate analysis demonstrated that the risk factors were the correction angle and pre-operative diameter of the C4/5 intervertebral foramen. The logistic regression model showed a correction angle exceeding 20° was critical for developing the palsy when C4/5 foraminal diameter reaches 4.1mm, and there is a higher risk when the C4/5 foraminal diameter is less than 2.7mm regardless of any correction. This study has indicated the risk factors of post-operative C5 palsy and the critical range of realignment of the cervical spine after posterior instrumented surgery.

Symmetrically Medial Bony Gutters for Open-door Laminoplasty

Observational cohort study. The authors modified open-door laminoplasty in a manner that creates a bony gutter symmetrically and more medially away from the medial border of the lateral mass. Cervical laminoplasty is becoming popular, but there was no definite position of bony gutter in performing open-door laminoplasty. All of the patients underwent our modified open-door laminoplasty with medial bony gutters. The bony gutter on the open side was made 3 mm medially apart from the medial border of the lateral mass, and an opposite gutter on the hinge side was drilled symmetrically to that on the open side while preserving the ventral cortex. The lamina was kept elevated using titanium miniplates bridging the lamina and facet joint on the open side. On the computed tomography, distance of the bony gutters and the cross-sectional area were measured from C4 to C6. This study included consecutive 61 patients (46 men and 15 women; mean age, 61.6 y old). The average distance of the right bony gutter was 3.43 mm and that of left bony gutter was 3.35 mm. The average cross-sectional area of preoperative and postoperative computed tomography was 189.9 and 281.8 mm in all patients, respectively. In all patients, although bony gutter was placed medially, the spinal canal area was expanded significantly (P < 0.0001). Postoperative C5 palsy developed in one of the 61 patients (1.6%). Compared with patients without C5 palsy, the right bony gutter was placed much closer to the medial border of the lateral mass in a patient with C5 palsy in whom we opened the lamina on the right side. Our modified open-door laminoplasty with symmetrically and medially placed bony gutters produced low incidence of postoperative C5 palsy with effective expansion of the spinal canal area.

Can Prophylactic Bilateral C4/C5 Foraminotomy Prevent Postoperative C5 Palsy After Open-Door Laminoplasty?

A prospective study. To evaluate the effectiveness of prophylactic C4/C5 microforaminotomy with open-door laminoplasty for cervical myelopathy in preventing postoperative C5 palsy. Postoperative C5 palsy is a common complication of cervical laminoplasty. Although the etiology of C5 palsy and preventive measures remain unclear, we hypothesize that C5 palsy is caused by C5 nerve root impairment induced by potential C4/C5 foraminal stenosis and posterior shifting of the spinal cord after laminoplasty. The study included 141 consecutive patients with cervical myelopathy (103 men and 38 women) who underwent open-door laminoplasty with prophylactic bilateral C4/C5 foraminotomy between 2009 and 2010. These were designated as the foraminotomy group (FG). One hundred forty-one consecutive patients (100 men and 41 women) who underwent open-door laminoplasty without prophylactic foraminotomy during 2006 to 2008 served as a control group. This was the nonforaminotomy group (NFG). The incidence of C5 palsy, operation time, blood loss, and the number of decompressed disc levels were recorded. The incidence of C5 palsy was 1.4% (2 of 141 cases) in the FG, and 6.4% (9 of 141 cases) in the NFG. The mean operation times were 129 and 102 minutes, respectively. There were significant differences in the incidence of C5 palsy and operation time (both comparisons, P < 0.05). There were no significant differences in blood loss or the number of decompressed disc levels (both comparisons, P > 0.05). Prophylactic bilateral C4/C5 microforaminotomy significantly decreased the incidence of postoperative C5 palsy. These results suggest that the main etiology of C5 palsy was C5 root impairment. However, 2 patients experienced C5 palsy despite undergoing prophylactic foraminotomy, which indicated that other factors including spinal cord impairment after acute decompression against cervical canal stenosis may also be considered as minor etiologies of C5 palsy. We conclude that prophylactic C4/C5 foraminotomy was an effective preventive measure against postoperative C5 palsy after laminoplasty.

Author’s reply to the letter to the editor of Hiroyuki Yoshihara concerning “C5 palsy following anterior decompression and spinal fusion for cervical degenerative diseases” by M. Hashimoto et al. (2010) Eur Spine J 19:1702–1710

We thank Dr. Yoshihara for his comments on our manuscript and below provide our responses to his remarks. It appears that cervical myelopathy is more prevalent in Japan than in the US [1]. This is partly because the Japanese people have narrower spinal canal diameter [2] and a higher incidence of patients have ossification of the posterior longitudinal ligament [3]; both of which are among the major risk factors for cervical myelopathy. In fact, in our 199 cases of anterior cervical surgery series, patients with cervical radiculopathy comprised only 6 cases, while there were as many as 193 patients with cervical myelopathy. In our series there were no cases of postoperative C5 palsy amongst patients with cervical radiculopathy. All cases of the postoperative C5 palsy were in patients who had cervical myelopathy. What we would like to emphasize here, is that pre-existing asymptomatic damage of anterior horn cells in the grey mater at C3–C4 and C4–C5 disc levels may contribute to the development of postoperative C5 palsy. There were no cases of postoperative C5 palsy in patients with single-level anterior cervical discectomy and fusion. Fifteen of the 17 C5 palsy cases occurred after two or more anterior corpectomy and spinal fusion procedures. We reported that the greater the number of corpectomy levels involved, the more likely the occurrence of postoperative C5 palsy. Ikenaga et al. [4] reviewed postoperative C5 palsy cases after anterior corpectomy and fusion and postulated that the extent of anterior dural expansion might have enhanced the incidence of postoperative C5 palsy. That mechanism may be somewhat different from the tethering effect of the nerve rootlet after cervical laminoplasty described by Tsuzuki et al. [5], but also has much in common in that postoperative C5 palsy occurs after longitudinal continuous and extended decompression of the cervical spinal cord. As Dr. Yoshihara mentions in his letter, some postoperative C5 palsy cases may resolve spontaneously. Postoperative C5 palsy cases with MMT grades of 3 or more have a tendency to fully recover without any additional treatment, as reported in our manuscript. It is probable that even patients with postoperative C5 palsy are themselves less aware of the onset and recovery of the muscle weakness. In our series radiating neck and shoulder pain was recognized 1–7 days (average 3.6) after surgery and muscle weakness developed 2–23 days (average 7.2) after surgery. So we are convinced that in order to detect the onset of postoperative C5 palsy accurately, it is essential to see the patients every day after surgery for at least 1 week. The etiology of postoperative C5 palsy remains controversial. We hope that our recently published paper that proposed a “double-lesion” hypothesis may contribute to elucidating the etiology of postoperative C5 palsy. We would like to conduct further studies of postoperative C5 palsy and shed light on this clinically important and unsolved issue.

Prospective Study and Multivariate Analysis of the Incidence of C5 Palsy After Cervical Laminoplasty

A prospective comparative study about the incidence of postoperative C5 palsy and multivariate analysis of the risk factors of C5 palsy. To clarify the risk factors of occurrence of C5 palsy after laminoplasty (LP) by comparing the 2 surgical procedures of open-door and double-door LP prospectively. The incidence of C5 palsy has been reported to average 4.6%, and there has been no difference of the incidence among surgical procedures. However, there were only indirect retrospective studies. A total of 146 patients who underwent the LP procedure between 2006 and 2007 were studied prospectively. In 2006, the patients were assigned to undergo the open-door LP, and in 2007, they were assigned to undergo the double-door LP. The incidence of postoperative C5 palsy was compared prospectively between these 2 LP procedures, and the risk factors of C5 palsy were detected with multivariate logistic regression analysis. Postoperative C5 palsy occurred in 7 of 73 cases after open-door LP (9.6%) and in 1 of 73 cases after double-door LP (1.4%). The incidence of C5 palsy after open-door LP was statistically higher than the one after double-door LP (P = 0.029), and open-door LP was recognized as a significant risk factor for postoperative C5 paralysis (odds ratio: 69.6, P = 0.043). In addition, ossification of posterior longitudinal ligament (OPLL) was recognized as a significant risk factor for postoperative C5 paralysis (odds ratio: 43.8, P = 0.048). This study showed significant evidence indicating the higher risk of postoperative C5 palsy in open-door LP than double-door LP. Because OPLL as well as open-door LP were recognized as the risk factors of C5 palsy, asymmetric decompression by open-door LP might introduce imbalanced rotational movement of spinal cord and result in C5 palsy. We recommend double-door LP to minimize the postoperative C5 palsy, in particularly, if the patient has OPLL.

C5 palsy following anterior decompression and spinal fusion for cervical degenerative diseases

Postoperative C5 palsy is a common complication after cervical spine decompression surgery. However, the incidence, prognosis, and etiology of C5 palsy after anterior decompression with spinal fusion (ASF) have not yet been fully established. In the present study, we analyzed the clinical and radiological characteristics of patients who developed C5 palsy after ASF for cervical degenerative diseases. The cases of 199 consecutive patients who underwent ASF were analyzed to clarify the incidence of postoperative C5 palsy. We also evaluated the onset and prognosis of C5 palsy. The presence of high signal changes (HSCs) in the spinal cord was analyzed using T2-weighted magnetic resonance images. C5 palsy occurred in 17 patients (8.5%), and in 15 of them, the palsy developed after ASF of 3 or more levels. Among ten patients who had a manual muscle test (MMT) grade ≤2 at the onset, five patients showed incomplete or no recovery. Sixteen of the 17 C5 palsy patients presented neck and shoulder pain prior to the onset of muscle weakness. In the ten patients with a MMT grade ≤2 at the onset, nine patients showed HSCs at the C3-C4 and C4-C5 levels. The present findings demonstrate that, in most patients with severe C5 palsy after ASF, pre-existing asymptomatic damage of the anterior horn cells at C3-C4 and C4-C5 levels may participate in the development of motor weakness in combination with the nerve root lesions that occur subsequent to ASF. Thus, when patients with spinal cord lesions at C3-C4 and C4-C5 levels undergo multilevel ASF, we should be alert to the possible occurrence of postoperative C5 palsy.

C5 Nerve Root Palsy After Cervical Laminoplasty and Posterior Fusion With Instrumentation

Consecutive case series. To compare the incidence and clinical characteristics of postoperative fifth cervical nerve root palsy (C5 palsy) in patients with cervical myelopathy treated by laminoplasty alone and laminoplasty with posterior instrumentation. In patients who have multilevel cervical myelopathy with reducible kyphosis or instability, the authors have performed laminoplasty together with instrumented fusion to restore lordosis and stability. There seems to be a high incidence of postoperative C5 palsy in these patients. Seventy-three patients with a mean age of 60.5 years and multilevel cervical myelopathy treated by laminoplasty from 1995 to 2005 were reviewed. Incidence, side, and severity of muscle weakness from patients with C5 palsy after posterior instrumented fusion (instrumented group) was compared with those without instrumentation (noninstrumented group). Radiologic parameters were assessed to identify predisposing factors. Overall 10 of 73 (14%) patients developed the C5 palsy, of which 5 (50%) of 10 patients were in instrumented group, and 5 of 63 (8%) patients were in noninstrumented. Three of 5 (60%) had the palsy on the same side of the opened lamina in the instrumented group, in the same proportion as the noninstrumented. Three (60%) patients in instrumented group developed deltoid weakness grade 1, but none in the noninstrumented had weaker than grade 3. All of the palsied in the instrumented group recovered within 2 years after surgery without removal of implant. Of the 5 patients with the palsy in the instrumented group, 3 had anterolisthesis before surgery and posterior translation of C4 on C5 by the surgery, and no patient without the palsy had the anterolisthesis. Posterior cervical fusion using instrumentation for restoration of lordotic alignment combined with laminoplasty is highly associated with severe postoperative C5 palsy in patients with multilevel cervical myelopathy and C4 anterolisthesis.

C5 palsy after decompression surgery for cervical myelopathy: review of the literature.

A literature review was conducted to integrate and compile available reports on postoperative C5 palsy. To review the clinical features, possible pathogenesis, and procedures for treatment and prevention of postoperative C5 palsy as a complication of surgery for cervical compression myelopathy. Although postoperative C5 palsy develops in approximately 5% of patients after decompression surgery of the cervical spine, its pathogenesis and the options for prevention and treatment remain unidentified and many controversies exist. We reviewed and analyzed papers published from 1986 to 2002 regarding C5 palsy as a postoperative complication. Statistical comparisons were made when appropriate. Postoperative C5 palsy is reported to occur in an average of 4.6% of patients after surgery for cervical compression myelopathy. No significant differences were noted between patients undergoing anterior decompression and fusion and laminoplasty, nor were distinctions apparent between unilateral hinge laminoplasty and French-door laminoplasty, or between cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament. Two theories were put forth to account for the pathogenesis of C5 palsy: nerve root injury and segmental spinal cord disorder. Neither of these hypotheses has been consistently supported and evidence to refute each hypothesis can be found in the literature. Recently, surgeons have advocated foraminotomy combined with laminoplasty to prevent or treat C5 palsy, but further studies into the efficacy of this procedure are needed. Although patients with C5 palsy generally have a good prognosis for neurologic and functional recovery, those with severe paralysis require significantly longer recovery times when compared to more mild cases. The incidence of postoperative C5 palsy has been reported at 4.6% after surgery for cervical compression myelopathy and this value has not varied with different surgical procedures or disease etiologies. 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 longer recovery times than the mild cases.