Comparison of Clinical Outcomes of Cervical Laminoplasty for Cervical Spondylotic Myelopathy: Double-Door With Lamina Staple, Single-Door With Miniplate, and Double-Door With Spacer—A 2-Year Follow-Up Study

Neurosurgery 92:1259–1268, 2023

There were few studies to compare the outcomes of different types of cervical laminoplasties.

OBJECTIVE: To compare the clinical outcomes of double-door cervical laminoplasty with lamina staple (double-door staple), single-door cervical laminoplasty with miniplate (singledoor miniplate), and double-door cervical laminoplasty with spacer (double-door spacer).

METHODS: The study involved 166 patients with cervical spondylotic myelopathy (CSM). Fifty-two patients underwent double-door staple, 63 patients underwent single-door miniplate, and 51 patients underwent double-door spacer. The clinical outcomes were measured.

RESULTS: There was no significant difference in Japanese Orthopedic Association score among the 3 groups (P > .05). The operation time was significantly shorter in double-door staple and single-door miniplate groups than in the double-door spacer group (P < .005). The estimated blood loss was significantly more in the single-door miniplate group than in double-door staple and double-door spacer groups (P < .005). The expansion ratio of cervical intraspinal cross-sectional area decreased in the order of double-door staple > double-door spacer > single-door miniplate. There were no significant differences in the expansion ratio of dural sac cross-sectional area among the 3 groups.

CONCLUSION: Double-door staple, double-door spacer, and single-door miniplate can achieve favorable clinical outcomes for CSM. The blood loss of double-door staple is less than that of single-door miniplate, and the operation time of double-door staple is shorter than that of double-door spacer. The mean expansion ratio of cervical intraspinal cross-sectional area decreased in the order of double-door staple > double-door spacer > single-door miniplate. Overall, double-door staple is a safe and innovative alternative choice for treatment of CSM.

Predictors for cervical kyphotic deformity following laminoplasty: a systematic review and meta-analysis

J Neurosurg Spine 38:4–13, 2023

Laminoplasty is a common treatment for cervical spondylotic myelopathy (CSM) and for ossification of the posterior longitudinal ligament (OPLL). However, approximately 21% of patients undergoing laminoplasty develop cervical kyphotic deformity (KD). Because of the high prevalence rate of KD, several studies have sought to identify predictors for this complication, but the findings remain highly inconsistent. Therefore, the authors performed a systematic review and meta-analysis to establish reliable preoperative predictors of KD.

METHODS PubMed, Scopus, and Web of Science databases were used to systematically extract potential references. The first phase of screening required the studies to be written in the English language, involve patients treated for CSM and/or OPLL via laminoplasty, and report postoperative cervical KD. The second phase required the studies to provide more than 10 patients and include a control group. The mean difference (MD) and odds ratio (OR) were calculated for continuous and dichotomous parameters. Study quality was evaluated using the Newcastle-Ottawa Scale. CSM and OPLL patients were further assessed by performing subgroup analyses.

RESULTS Thirteen studies comprising patients who developed cervical KD (n = 296) and no KD (n = 1254) after receiving cervical laminoplasty for CSM or OPLL were included in the meta-analysis. All studies were retrospective cohorts and were rated as high quality. In the combined univariate analysis of CSM and OPLL patients undergoing laminoplasty, statistically significant predictors for postoperative KD included age (MD 2.22, 95% CI 0.16–4.27, p = 0.03), preoperative BMI (MD 0.85, 95% CI 0.06–1.63, p = 0.04), preoperative C2–7 range of flexion (MD 10.42, 95% Cl 4.24–16.59, p = 0.0009), preoperative C2–7 range of extension (MD −4.59, 95% CI −6.34 to −2.83, p < 0.00001), and preoperative center of gravity of the head to the C7 sagittal vertical axis (MD 26.83, 95% CI 9.13–44.52, p = 0.003). Additionally, among CSM patients, males were identified as having a greater risk for postoperative KD (OR 1.73, 95% CI 1.02–2.93, p = 0.04).

CONCLUSIONS The findings from this study currently provide the largest and most reliable review on preoperative predictors for cervical KD after laminoplasty. Given that several of the included studies identified optimal cutoff points for the variables that are significantly associated with KD, further investigation into the development of a preoperative risk scoring system that can accurately predict KD in the clinical setting is encouraged.

Impact of focal apex angle on postoperative decompression status of the spinal cord and neurological recovery after cervical laminoplasty

J Neurosurg Spine 35:410–418, 2021

Although anterior compression factors and cervical alignment affect neural decompression, cervical laminoplasty may be used to achieve indirect posterior decompression. The focal apex (FA) angle of the anterior compression factor of the spine represents the degree of anterior prominence toward the spinal cord. The authors investigated the mechanism underlying the influence of FA angle and cervical alignment on spinal cord alignment (SCA) after laminoplasty, including how high-intensity signal cord change (HISCC) on preoperative T2-weighted MRI (T2-MRI) may affect neurological improvement.

METHODS We performed a retrospective study of patients who underwent laminoplasty for CSM or OPLL at two hospitals (Kanto Rosai Hospital, Kawasaki City, and Yokohama Minami Kyousai Hospital, Yokohama City, Japan) between April 2004 and March 2015. In total, 109 patients (mean age 67.3 years) with cervical compression myelopathy were included. FA angle was defined as the preoperative angle between the lines from the top of the prominence to the upper and lower adjacent vertebrae. Preoperative cervical alignment was measured between the C2 and C7 vertebrae (C2–7 angle). MRI was used to classify SCA as lordosis (type-L SCA), straight (type-S), local kyphosis (type-LK), or kyphosis (type-K). Preoperative HISCC was investigated by using T2-MRI. Neurological status was evaluated by using the Japanese Orthopaedic Association score.

RESULTS The mean preoperative FA and C2–7 angles were 32.1° and 12.4°, respectively. Preoperative SCA was type- L or type-S in 53 patients. The neurological recovery rate (NRR) was significantly higher for patients with preoperative type-L and type-S SCA (51.4% for those with type-L and 45.0% for those with type-S) than for patients with other types (35.3% for those with type-LK and 31.7% for those with type-K). Among patients with preoperative type-L or type-S SCA, 87.3% maintained SCA; however, 5/12 (41.7%) patients with a preoperative average C2–7 angle < 12.4° and an average FA angle > 32.1° had postoperative type-LK or type-K SCA. SCA changed to type-L or type-S in 13.0% of patients with preoperative type-LK or type-K SCA. Moreover, in these patients, FA angle was significantly smaller and NRR was significantly higher than in other patients in whom postoperative SCA remained type-LK or type-K. Preoperative T2- MRI showed 73 patients with HISCC (43 with type-L and type-S, and 30 with type-LK and type-K SCA) and 36 without HISCC (20 with type-L and type-S, and 16 with type-LK and type-K SCA); the NRRs of these patients were 42.6% and 41.2%, respectively. No significant differences in SCA or NRR were observed between patients with and without HISCC.

CONCLUSIONS NRR depends on preoperative SCA type; however, it is possible to change the type of SCA after laminoplasty. Preoperative FA and C2–7 angles influence change in SCA; therefore, they are important parameters for successful decompression with cervical laminoplasty.

Volumetric analysis of bilateral spinal canal decompression via hemilaminectomy versus laminoplasty in cervical spondylotic myelopathy

Acta Neurochirurgica (2020) 162:2069–2074

Cervical spondylotic myelopathy (CSM) is a degenerative process of the cervical spine requiring surgical decompression to prevent neurological deterioration. While both anterior and posterior approaches yield satisfactory results, posterior decompression is preferred in cases of the multilevel disease. In 2015, we described a muscle-sparing, novel technique of bilateral osteoligamentous decompression via hemilaminectomy (OLD) for CSM. In this study, we investigate whether this technique offers comparable volumetric results to laminoplasty in terms of spinal canal enlargement and whether this technique can yield significant clinical improvement.

Methods Patients undergoing OLD due to CSM were prospectively enrolled in this study and then matched to and compared with a historic cohort of patients with CSM treated by laminoplasty. An independent sample t test was performed to analyze whether the volumetric gain in the two separate groups was statistically significant. Patients in the OLD cohort were clinically evaluated with the mJOA score preoperatively and 3 months postoperatively. To assess clinical improvement, a paired sample t test was performed.

Results A total of 38 patients were included in the analysis: 19 underwent OLD and 19 underwent laminoplasty. Both groups were well matched in terms of sex, age, preoperative spinal canal volume, and involved levels. Both surgical methods yielded statistically significant volumetric gain in the cervical spinal canal, but a trend towards a greater volume gain was seen in the OLD group. In the OLD group, a statistically significant clinical improvement was also demonstrated.

Conclusions Our study reveals that OLD can yield a comparable extent of decompression to laminoplasty in CSM while also delivering statistically significant clinical improvement.

The Efficacy of Ultrasonic Bone Scalpel for Unilateral Cervical Open-Door Laminoplasty: A Randomized Controlled Trial

Neurosurgery 86:825–834, 2020

In cervical open-door laminoplasty for cervical myelopathy, a high-speed rotatory drill and rongeurs are used to make unicortical troughs and bicortical openings in the laminae. The lamina is reflected at the trough to enlarge the spinal canal, followed by bone healing on the hinge side to stabilize laminoplasty. The ultrasonic bone scalpel (UBS) has been used due to theoretical advantages including a better hinge union rate, less soft tissue trauma, less neurological injury, and shorter operative time.

OBJECTIVE: To assess the superiority of UBS for hinge union compared to the drill through randomized controlled trial.

METHODS: In 190 randomly allocated cervical myelopathy patients, the trough and opening at the lamina were made using either the drill (n = 95) or UBS (n = 95) during 2015 to 2018. The primary outcome was the hinge union rate on 6-mo postoperative computed tomography. Secondary outcomes included the hinge union rate at 12 mo, the operative time, intraoperative/postoperative bleeding, neurological injury, complications, and clinical outcomes over a 24-mo follow-up.

RESULTS: Hinge union in all laminae was achieved in 60.0% (drill) and 43.9% (UBS) of patients at 6mo (intention-to-treat analysis; P = .02; odds ratio, 2.1) and in 91.9% (drill) and 86.5% (UBS) at 12mo. Dural injury only occurred in the drill group (2.1%), and the UBS group showed significantly less intraoperative bleeding (P < .01). The other secondary outcomes did not differ between groups.

CONCLUSION: The hinge union rate was inferior in the UBS group at 6mo postoperatively, but UBS was efficacious in reducing dural injuries and bleeding.

Modified Laminoplasty Preserving the Posterior Deep Extensor Insertion into C2 Improves Clinical and Radiologic Results Compared with Conventional Laminoplasty: A Meta-Analysis

World Neurosurg. (2018) 111:157-165

Whether modified laminoplasty is better than conventional laminoplasty is unclear. Thus, a meta-analysis comparing the outcomes of preserving or repairing the posterior deep extensor insertion to C2 in laminoplasty was conducted for patients with multilevel cervical spondylotic myelopathy (MCSM).

METHODS: Several electronic databases were chosen to search for relevant studies. The primary indices included preoperative and postoperative Japanese Orthopaedic Association (JOA) scores, JOA recovery rate, muscle atrophy rate, preoperative and postoperative range of motion (ROM), ROM decrease rate, and incidence of axial pain. Results are expressed as odds ratios with 95% confidence intervals for the dichotomous outcomes and mean differences for continuous outcomes.

RESULTS: Eight studies involving 763 patients were included in this study. The postoperative cervical ROM was significantly higher in the modified group (P [ 0.01, MD [ 3.0 [0.66, 5.35]), as was the cervical posterior muscle volume (P [ 0.02, MD [ 28.28 [4.42, 52.3]) and the operation time (MD [ L45.04, 95% CI L49.79, L40.29; P < 0.01). The incidence of axial symptoms in the modified group was lower than that in the conventional group (P < 0.01, OR 0.28 [0.17, 0.46]), as was the rate of decrease of cervical ROM (P [ 0.004, MD [ L6.72 [L11.25, 2.19]). There was no significant difference (P > 0.05) between the groups in blood loss, preoperative and postoperative JOA score, or JOA recovery rate.

CONCLUSIONS: Modified laminoplasty had shorter operation times, a lower incidence of axial pain, a higher cervical ROM, and a lower atrophy rate compared with conventional laminoplasty. The clinical and radiologic results of modified laminoplasty have been partly superior to those of conventional laminoplasty to date.

Microendoscopic laminotomy versus conventional laminoplasty for cervical spondylotic myelopathy: 5-year follow-up study

J Neurosurg Spine 27:403–409, 2017

The goal of this study was to characterize the long-term clinical and radiological results of articular segmental decompression surgery using endoscopy (cervical microendoscopic laminotomy [CMEL]) for cervical spondylotic myelopathy (CSM) and to compare outcomes to conventional expansive laminoplasty (ELAP).

METHODS Consecutive patients with CSM who required surgical treatment were enrolled. All enrolled patients (n = 78) underwent CMEL or ELAP. All patients were followed postoperatively for more than 5 years. The preoperative and 5-year follow-up evaluations included neurological assessment (Japanese Orthopaedic Association [JOA] score), JOA recovery rates, axial neck pain (using a visual analog scale), the SF-36, and cervical sagittal alignment (C2–7 subaxial cervical angle).

RESULTS Sixty-one patients were included for analysis, 31 in the CMEL group and 30 in the ELAP group. The mean preoperative JOA score was 10.1 points in the CMEL group and 10.9 points in the ELAP group (p > 0.05). The JOA recovery rates were similar, 57.6% in the CMEL group and 55.4% in the ELAP group (p > 0.05). The axial neck pain in the CMEL group was significantly lower than that in the ELAP group (p < 0.01). At the 5-year follow-up, cervical alignment was more favorable in the CMEL group, with an average 2.6° gain in lordosis (versus 1.2° loss of lordosis in the ELAP group [p < 0.05]) and lower incidence of postoperative kyphosis.

CONCLUSIONS CMEL is a novel, less invasive technique that allows for multilevel posterior cervical decompression for the treatment of CSM. This 5-year follow-up data demonstrates that after undergoing CMEL, patients have similar neurological outcomes to conventional laminoplasty, with significantly less postoperative axial pain and improved subaxial cervical lordosis when compared with their traditional ELAP counterparts.

Clinical Outcomes of Cervical Laminoplasty

Neurosurgery 80:934–941, 2017

Laminoplasty is an established treatment for cervical myelopathy. Multiple variations have emerged, many advocating the use of allograft, but controversy persists.

OBJECTIVE: To assess medium-term clinical outcomes in patientswho underwent laminoplasty with autograft at our institution.

METHODS: Thirty-two consecutive patients (19 male, 13 female, average age 66 yr) from our prospective outcome registry that underwent cervical laminoplasty between 2009 and 2013 were reviewed. Computed tomography (CT) scan was performed immediately postoperatively and at 6-mo follow-up. Parameters included patient perception of outcome, Nurick score, Neck Disability Index (NDI), visual analog scale for neck pain, and SF-36.

RESULTS: On retrospective analysis, all patients felt improved at 3 mo postoperatively; at 2 yr, this rate was 91%. Improvements were seen in Nurick scores, from 3.16 ± 0.9 preoperatively to 1.94 ± 0.8 at 2 yr; NDI score from 28.7% ± 9% preoperatively to 20.8% ± 9.6% at 2 yr; visual analog scale from2.8 ± 1.2 preoperatively to 1.7 ± 0.9 at 2 yr; and SF-36 physical component summary from 27.9±10 preoperatively to 37.8±11.9 at 2 yr. All values reached significance at all follow-up points (P < .05) with the exception of 6-mo NDI values (P = .062). No C5 palsy, graft complications, or reclosure was observed in any patient during the follow-up period.

CONCLUSION: Laminoplasty with autograft is a safe and effective method to treat cervical myelopathy,with good medium-term clinical outcome. No reclosures were observed. Bony fusion was seen in all cases on CT scan. Our study found good outcomes in the performance of open-door laminoplasty without hardware, in the treatment of cervical stenosis.

 

Cervical laminoplasty developments and trends, 2003–2013: a systematic review

Laminoplasty

J Neurosurg Spine 23:24–34, 2015

Despite extensive clinical experience with laminoplasty, the efficacy of the procedure and its advantages over laminectomy remain unclear. Specific clinical elements, such as incidence or progression of kyphosis, incidence of axial neck pain, postoperative cervical range of motion, and incidence of postoperative C-5 palsies, are of concern. The authors sought to comprehensively review the laminoplasty literature over the past 10 years while focusing on these clinical elements.

Methods The authors conducted a literature search of articles in the Medline database published between 2003 and 2013, in which the terms “laminoplasty,” “laminectomy,” and “posterior cervical spine procedures” were used as key words. Included was every single case series in which patient outcomes after a laminoplasty procedure were reported. Excluded were studies that did not report on at least one of the above-mentioned items.

Results A total of 103 studies, the results of which contained at least 1 of the prespecified outcome variables, were identified. These studies reported 130 patient groups comprising 8949 patients. There were 3 prospective randomized studies, 1 prospective nonrandomized alternating study, 15 prospective nonrandomized data collections, and 84 retrospective reviews. The review revealed a trend for the use of miniplates or hydroxyapatite spacers on the open side in Hirabayashi-type laminoplasty or on the open side in a Kurokawa-type laminoplasty. Japanese Orthopaedic Association (JOA) scoring was reported most commonly; in the 4949 patients for whom a JOA score was reported, there was improvement from a mean (± SD) score of 9.91 (± 1.65) to a score of 13.68 (± 1.05) after a mean follow-up of 44.18 months (± 35.1 months). The mean preoperative and postoperative C2–7 angles (available for 2470 patients) remained stable from 14.17° (± 0.19°) to 13.98° (± 0.19°) of lordosis (average follow-up 39 months). The authors found significantly decreased kyphosis when muscle/posterior element–sparing techniques were used (p = 0.02). The use of hardware in the form of hydroxyapatite spacers or miniplates did not influence the progression of deformity (p = 0.889). An overall mean (calculated from 2390 patients) of 47.3% loss of range of motion was reported. For the studies that used a visual analog scale score (totaling 986 patients), the mean (cohort size–adjusted) postoperative pain level at a mean follow-up of 29 months was 2.78. For the studies that used percentages of patients who complained of postoperative axial neck pain (totaling 1249 patients), the mean patient number–adjusted percentage was 30% at a mean follow-up of 51 months. The authors found that 16% of the studies that were published in the last 10 years reported a C-5 palsy rate of more than 10% (534 patients), 41% of the studies reported a rate of 5%–10% (n = 1006), 23% of the studies reported a rate of 1%–5% (n = 857), and 12.5% reported a rate of 0% (n = 168).

Conclusions Laminoplasty remains a valid option for decompression of the spinal cord. An understanding of the importance of the muscle-ligament complex, plus the introduction of hardware, has led to progress in this type of surgery. Reporting of outcome metrics remains variable, which makes comparisons among the techniques difficult.

Anterior corpectomy versus posterior laminoplasty for multilevel cervical myelopathy

cervical spine stenosis

Eur Spine J (2014) 23:362–372

Surgical strategy for multilevel cervical myelopathy resulting from cervical spondylotic myelopathy (CSM) or ossification of posterior longitudinal ligament (OPLL) still remains controversial. There are still questions about the relative benefit and safety of direct decompression by anterior corpectomy (CORP) versus indirect decompression by posterior laminoplasty (LAMP).

Objective To perform a systematic review and metaanalysis evaluating the results of anterior CORP compared with posterior LAMP for patients with multilevel cervical myelopathy. Methods Systematic review and meta-analysis of cohort studies comparing anterior CORP with posterior LAMP for the treatment of multilevel cervical myelopathy due to CSM or OPLL from 1990 to December 2012. An extensive search of literature was performed in Pubmed, Embase, and the Cochrane library. The quality of the studies was assessed according to GRADE. The following outcome measures were extracted: pre- and postoperative Japanese orthopedic association (JOA) score, neurological recovery rate (RR), surgical complications, reoperation rate, operation time and blood loss. Two reviewers independently assessed each study for quality and extracted data. Subgroup analysis was conducted according to the mean number of surgical segments.

Results A total of 12 studies were included in this review, all of which were prospective or retrospective cohort studies with relatively low quality. The results indicated that the mean JOA score system for cervical myelopathy and the neurological RR in the CORP group were superior to those in the LAMP group when the mean surgical segments were<3, but were similar between the two groups in the case of the mean surgical segments equal to 3 or more. There was no statistical difference in the surgical complication rate between the two groups when the mean surgical segments<3, but were significantly higher incidences of surgical complications and complication-related reoperation in the CORP group compared with the LAMP group in the case of the mean surgical segments equal to 3 or more. Besides, the operation time in the CORP group was longer than that in the LAMP group, and the average blood loss was significantly more in the CORP group compared with the LAMP group.

Conclusion Based on the results above, anterior CORP and fusion is recommended for the treatment of multilevel cervical myelopathy when the involved surgical segments were<3. Given the higher rates of surgical complications and complication-related reoperation and the higher surgical trauma associated with multilevel CORP, however, it is suggested that posterior LAMP may be the preferred method of treatment for multilevel cervical myelopathy when the involved surgical segments were equal to 3 or more. In addition, taking the limitations of this study into consideration, it was still not appropriate to draw a strong conclusion claiming superiority for CORP or LAMP. A well-designed, prospective, randomized controlled trial is necessary to provide objective data on the clinical results of both procedures.

Outcomes of surgical intervention for cervical spondylotic myelopathy accompanying local kyphosis

cervical kyphosis

Eur Spine J (2014) 23:341–346

The surgical strategy for cervical spondylotic myelopathy (CSM) accompanying local kyphosis is controversial. The purpose of the present study was to compare and evaluate the outcomes of two types of surgery for CSM accompanying local kyphosis: (1) laminoplasty alone (LP) and (2) posterior reconstruction surgery (PR) in which we corrected the local kyphosis using a pedicle screw or lateral mass screw.

Methods Sixty patients who presented with local kyphosis exceeding 5º were enrolled. LP and PR were each performed on a group of 30 of these patients; 30 CSM patients without local kyphosis, who had undergone LP, were used as controls. The follow-up period was 2 years or longer. Preoperative local kyphosis angles in LP and PR were 8.3 ± 4.4 and 8.8 ± 5.7, respectively. Preoperative C2–7 angles in LP, PR and controls were -1.7 ± 9.6, -0.4 ± 7.2 and -12.0 ± 5.6, respectively. The recovery rate of the JOA score, local kyphosis angle and C2–7 angle at post-op and follow-up were compared between the groups.

Results The recovery rate of the JOA score in the LP group (32.6 %) was significantly worse than that in the PR group (44.5 %) and that of controls (53.8 %). Local kyphosis angles in the PR and LP groups at follow-up were 4.0 ± 8.6 and 8.0 ± 6.0, respectively. However, although the C2–7 angle at follow-up was improved to -11.1 ± 12.7 in PR, and maintained at -11.6 ± 6.2 in controls, it deteriorated to 0.5 ± 12.7 in LP.

Conclusions The present study is the first to compare the outcomes between LP alone and PR for CSM accompanying local kyphosis. It revealed that PR resulted in a better clinical outcome than did LP alone. This result may be due to reduction of local kyphosis, stabilization of the unstable segment, and/or the maintenance of C2–7 angle until follow- up in the PR group.

Ultrasonographic quantification of spinal cord and dural pulsations during cervical laminoplasty in patients with compressive myelopathy

Eur Spine J (2012) 21:2450–2455

Pulsatile movements of the dura mater have been interpreted as a sign that the cord is free within the subarachnoid space, with no extrinsic compression. However, the association between restoration of pulsation and adequate decompression of the spinal cord has not been established. The present study investigated the relationship between the extent of spinal cord decompression and spinal cord and dural pulsations based on quantitative analysis of intraoperative ultrasonography (US).

Methods Eighty-five consecutive patients (55 males, 30 females; mean age, 64 ± 13 years) who underwent cervical double-door laminoplasty to relieve compressive myelopathy were enrolled. Spinal cord decompression status was classified as: Type 1 (non-contact), the subarachnoid space was retained on the ventral side of the cord, Type 2 (contact and apart), the cord showed both contact with and separation from the anterior element of the cervical spine, or Type 3 (contact), the cord showed continuous contact with the anterior element of the cervical spine. Spinal cord and dura mater dynamics were quantitatively analyzed using automatic video-tracking software. Furthermore, the intensity of spinal and dural pulsation was compared with the recovery of motor function at 1 year after surgery as measured by increase in the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ).

Results Spinal cord pulsation amplitude ranged from 0.01 to 0.84 mm (mean 0.30 ± 0.16 mm) and dural pulsation amplitude ranged from 0.01 to 0.38 mm (mean 0.14 ± 0.08 mm). Average spinal cord pulsation amplitude in Type 2 patients was significantly larger than that in the other groups, whereas, average dural pulsation amplitudes were similar for all three groups. There was a significant correlation between spinal cord and dural pulsation amplitudes in Type 1 patients, but not in Type 2 or Type 3 patients. Type 3 patients showed a particularly poor correlation between spinal cord and dural pulsations. Spinal cord pulsation amplitude was moderately correlated with the recovery of motor function evaluated by JOACMEQ.

Conclusion The present results suggest that restoration of dural pulsation is not an adequate indicator of sufficient decompression of the spinal cord following a surgical procedure.

Complications associated with the surgical treatment of cervical spondylotic myelopathy

J Neurosurg Spine 16:425–432, 2012. (http://thejns.org/doi/abs/10.3171/ 2012.1.SPINE11467) 

Rates of complications associated with the surgical treatment of cervical spondylotic myelopathy (CSM) are not clear. Appreciating these risks is important for patient counseling and quality improvement. The authors sought to assess the rates of and risk factors associated with perioperative and delayed complications associated with the surgical treatment of CSM.

Methods. Data from the AOSpine North America Cervical Spondylotic Myelopathy Study, a prospective, multicenter study, were analyzed. Outcomes data, including adverse events, were collected in a standardized manner and externally monitored. Rates of perioperative complications (within 30 days of surgery) and delayed complications (31 days to 2 years following surgery) were tabulated and stratified based on clinical factors.

Results. The study enrolled 302 patients (mean age 57 years, range 29–86) years. Of 332 reported adverse events, 73 were classified as perioperative complications (25 major and 48 minor) in 47 patients (overall perioperative complication rate of 15.6%). The most common perioperative complications included minor cardiopulmonary events (3.0%), dysphagia (3.0%), and superficial wound infection (2.3%). Perioperative worsening of myelopathy was reported in 4 patients (1.3%). Based on 275 patients who completed 2 years of follow-up, there were 14 delayed complications (8 minor, 6 major) in 12 patients, for an overall delayed complication rate of 4.4%. Of patients treated with anterior-only (n = 176), posterior-only (n = 107), and combined anterior-posterior (n = 19) procedures, 11%, 19%, and 37%, respectively, had 1 or more perioperative complications. Compared with anterior-only approaches, posterior-only approaches had a higher rate of wound infection (0.6% vs 4.7%, p = 0.030). Dysphagia was more common with combined anterior-posterior procedures (21.1%) compared with anterior-only procedures (2.3%) or posterior-only procedures (0.9%) (p < 0.001). The incidence of C-5 radiculopathy was not associated with the surgical approach (p = 0.8). The occurrence of perioperative complications was associated with increased age (p = 0.006), combined anterior-posterior procedures (p = 0.016), increased operative time (p = 0.009), and increased operative blood loss (p = 0.005), but it was not associated with comorbidity score, body mass index, modified Japanese Orthopaedic Association score, smoking status, anterior-only versus posterior-only approach, or specific procedures. Multivariate analysis of factors associated with minor or major complications identified age (OR 1.029, 95% CI 1.002–1.057, p = 0.035) and operative time (OR 1.005, 95% CI 1.002–1.008, p = 0.001). Multivariate analysis of factors associated with major complications identified age (OR 1.054, 95% CI 1.015–1.094, p = 0.006) and combined anterior-posterior procedures (OR 5.297, 95% CI 1.626–17.256, p = 0.006).

Conclusions. For the surgical treatment of CSM, the vast majority of complications were treatable and without long-term impact. Multivariate factors associated with an increased risk of complications include greater age, increased operative time, and use of combined anterior-posterior procedures.

Can Elderly Patients Recover Adequately After Laminoplasty?

Spine 2012 ; 37 : 667 – 671 

This was a prospective clinical comparative study of surgical outcomes for patients with cervical spondylotic myelopathy (CSM).

Objective. The purpose of this study was to compare the surgical outcomes between nonelderly and elderly patients with CSM who underwent laminoplasty.

Summary of Background Data. Age at the time of surgery influences the surgical outcome. We designed a large-scale study of the surgical outcome for CSM from a single operative procedure used exclusively in elderly patients.

Methods. A total of 520 consecutive patients with CSM (331 men; 189 women) who underwent double-door laminoplasty were included. Mean age was 62 years (range, 23–93), and mean duration of disease was 20.1 ± 32.0 months. Average postoperative followup period was 33.3 ± 15.7 months. Patients were divided into 3 groups by age: nonelderly ( < 65 years), young-old (65–74 years), and old-old ( ≥ 75 years). The number of patients in each group was 287, 143, and 90. Pre- and postoperative neurological status was evaluated using the Japanese Orthopaedic Association scoring system for cervical myelopathy (JOA score).

Results. Mean pre- and postoperative JOA scores in nonelderly, young-old, and old-old groups were 11.0 and 14.4, 10.2 and 13.2, and 8.7 and 11.8 points, respectively. The elderly group showed significantly low recovery rates of JOA scores compared with the nonelderly group ( P < 0.0001). However, mean achieved JOA scores (postoperative JOA score − preoperative JOA score) were 3.4, 3.0, and 3.1 in nonelderly, young-old, and old-old groups, respectively, with no significant difference among these groups ( P = 0.17).

Conclusion. Pre- and postoperative JOA scores were low in elderly patients. However, the achieved JOA score was almost similar among the 3 groups. Thus, elderly patients could obtain reasonable recovery after cervical laminoplasty.

A Prospective, Randomized Trial Comparing Expansile Cervical Laminoplasty and Cervical Laminectomy and Fusion for Multilevel Cervical Myelopathy

Neurosurgery 70:264–277, 2012 DOI: 10.1227/NEU.0b013e3182305669

Controversy exists as to the best posterior operative procedure to treat multilevel compressive cervical spondylotic myelopathy.

OBJECTIVE: To determine clinical, radiological, and patient satisfaction outcomes between expansile cervical laminoplasty (ECL) and cervical laminectomy and fusion (CLF).

METHODS: We performed a prospective, randomized study of ECL vs CLF in patients suffering from cervical spondylotic myelopathy. End points included the Short Form-36, Neck Disability Index, Visual Analog Scale, modified Japanese Orthopedic Association score, Nurick score, and radiographic measures.

RESULTS: A survey of academic North American spine surgeons (n = 30) demonstrated that CLF is the most commonly used (70%) posterior procedure to treat multilevel spondylotic cervical myelopathy. A total of 16 patients were randomized: 7 to CLF and 9 to ECL. Both groups showed improvements in their Nurick grade and Japanese Orthopedic Association score postoperatively, but only the improvement in the Nurick grade for the ECL group was statistically significant (P < .05). The cervical range of motion between C2 and C7 was reduced by 75% in the CLF group and by only 20% in the ECL group in a comparison of preoperative and postoperative range of motion. The overall increase in canal area was significantly (P < .001) greater in the CLF group, but there was a suggestion that the adjacent level was more narrowed in the CLF group in as little as 1 year postoperatively.

CONCLUSION: In many respects, ECL compares favorably to CLF. Although the patient numbers were small, there were significant improvements in pain measures in the ECL group while still maintaining range of motion. Restoration of spinal canal area was superior in the CLF group.

Cervical Laminoplasty as a Management Option for Patients With Cervical Spondylotic Myelopathy: A Series of 40 Patients

Neurosurgery 67:272-277, 2010 DOI: 10.1227/01.NEU.0000371981.83022.B1

Cervical spondylotic myelopathy (CSM) is one of the leading causes of spinal cord dysfunction in the adult population. Laminoplasty is an effective decompressive procedure for the treatment of CSM.

OBJECTIVE:We present our experience with 40 patients who underwent cervical laminoplasty using titanium miniplates for CSM.

METHODS:We performed a retrospective review of the medical records of a consecutive series of patients with CSM treated with laminoplasty at the University of Rochester Medical Center or Rochester General Hospital. We documented patient demographic data, presenting symptoms, and postoperative outcome. Data are also presented regarding the general cost of constructs for a hypothetical 3-level fusion.

RESULTS: Forty patients underwent cervical laminoplasty; all were available for follow-up. The mean number of levels was 4. All patients were myelopathic, and 17 (42.5%) had signs of radiculopathy preoperatively. Preoperatively, 62.5% of patients had a Nurick grade of 2 or worse. The average follow-up was 31.3 months. The median length of stay was 48 hours. On clinical evaluation, 36 of 40 patients demonstrated an improvement in their myelopathic symptoms; 4 were unchanged. Postoperative kyphosis did not develop in any patients.

CONCLUSION: The management of CSM for each of its etiologies remains controversial. As demonstrated in our series, laminoplasty is a cost-effective, decompressive procedure for the treatment of CSM, providing a less destabilizing alternative to laminectomy while preserving mobility. Cervical laminoplasty should be considered in the management of multilevel spondylosis because of its ease of exposure, ability to decompress, effective preservation of motion, maintenance of spinal stability, and overall cost.

Short-term Progressive Spinal Deformity Following Laminoplasty Versus Laminectomy for Resection of Intradural Spinal Tumors: Analysis of 238 Patients

Neurosurgery 66:1005-1012, 2010 DOI: 10.1227/01.NEU.0000367721.73220.C9

Gross total resection of intradural spinal tumors can be achieved in the majority of cases with preservation of long-term neurological function. However, postoperative progressive spinal deformity complicates outcome in a subset of patients after surgery. We set out to determine whether the use of laminoplasty (LP) vs laminectomy (LM) has reduced the incidence of subsequent spinal deformity following intradural tumor resection at our institution.

METHODS:We retrospectively reviewed the records of 238 consecutive patients undergoing resection of intradural tumor at a single institution. The incidence of subsequent progressive kyphosis or scoliosis, perioperative morbidity, and neurological outcome were compared between the LP and LM cohorts.

RESULTS: One hundred eighty patients underwent LM and 58 underwent LP. Patients were 46 ± 19 years old with median modified McCormick score of 2. Tumors were intramedullary in 102 (43%) and extramedullary in 102 (43%). All baseline clinical, radiographic, and operative variables were similar between the LP and LM cohorts. LP was associated with a decreased mean length of hospitalization (5 vs 7 days; P = .002) and trend of decreased incisional cerebrospinal fluid leak (3% vs 9%; P = .14). Following LP vs LM, 5 (9%) vs 21 (12%) patients developed progressive deformity (P = .728) a mean of 14 months after surgery. The incidence of progressive deformity was also similar between LP vs LM in pediatric patients < 18 years of age (43% vs 36%), with preoperative scoliosis or loss of cervical/lumbar lordosis (28% vs 22%), or with intramedullary tumors (11% vs 11%).

CONCLUSION: LP for the resection of intradural spinal tumors was not associated with a decreased incidence of short-term progressive spinal deformity or improved neurological function. However, LP may be associated with a reduction in incisional cerebrospinal fluid leak. Longer-term follow-up is warranted to definitively assess the long-term effect of LP and the risk of deformity over time.

Surgical results of cervical myelopathy in patients older than 80 years of age

J Neurosurg Spine 11:421–426, 2009. DOI: 10.3171/2009.4.SPINE08584

In this prospective analysis the authors describe the clinical results of surgical treatment in patients > 80 years of age in whom spinal function was evaluated with motor evoked potential (MEPs) monitoring.

Methods. The authors included 57 patients > 80 years of age who were suspected of having cervical myelopathy. The mean age of the patients was 83.0 years (range 80–90 years). The central motor conduction time (CMCT) was calculated from the latencies of the MEPs following transcranial magnetic stimulation and from M and F waves fol- lowing peripheral nerve stimulation.

Results. Preoperative electrophysiological evaluation demonstrated significant elongation of CMCT or abnor- malities in MEP waveforms in 37 patients (65%), and 35 patients of these underwent laminoplasty. In 30 patients cervical spondylotic myelopathy was diagnosed and 5 patients ossification of the posterior longitudinal ligament was diagnosed. The preoperative mean Japanese Orthopaedic Association Scale score was 8.6 (range 3–12.5) and the mean postoperative score was 12.6 (range 6–14.5) with an average recovery rate of 45% (range −21 to 100%). There were no major complications in any of the patients during the operative period and there were no cases of death resulting from operative intervention.

Conclusions. Sufficient clinical results are expected even in patients with myelopathy who are older than 80 years of age, provided the patients are correctly selected by electrophysiological evaluation with MEPs and CMCT.