Objective
To investigate whether preoperative T1 slope (T1S) in MRI can predict the changes of cervical curvature after expansive open-door laminoplasty (EOLP) in patients with cervical spondylotic myelopathy, so as to make up for the shortcomings of difficult measurement in X-ray film.
Methods
The clinical data of 36 patients with cervical spondylotic myelopathy who underwent EOLP were retrospectively analysed. There were 21 males and 15 females with an average age of 55.8 years (range, 37-73 years) and an average follow-up time of 14.3 months (range, 12-24 months). The preoperative X-ray films at dynamic position, CT, and MRI of cervical spine before operation, and the anteroposterior and lateral X-ray films at last follow-up were taken out to measure the following sagittal parameters. The parameters included C2-C7 Cobb angle and C2-C7 sagittal vertical axis (C2-C7 SVA) in all patients before operation and at last follow-up; preoperative T1S were measured in MRI, and the patients were divided into larger T1S group (T1S>19°, group A) and small T1S group (T1S≤19°, group B) according to the median of T1S, and the preoperative T1S, C2-C7 Cobb angle, C2-C7 SVA, and the C2-C7 Cobb angle and C2-C7 SVA at last follow-up, difference in axial distance (the difference of C2-C7 SVA before and after operation), postoperative curvature loss (the difference of C2-C7 Cobb angle before and after operation), the number of patients whose curvature loss was more than 5° after operation, and the number of patients whose kyphosis changed (C2-C7 Cobb angle was less than 0° after operation).
Results
The C2-C7 Cobb angle at last follow-up was significantly decreased when compared with preoperative value (t=8.000, P=0.000), but there was no significant difference in C2-C7 SVA between pre- and post-operation (t=–1.842, P=0.074). The preoperative T1S was (19.69±3.39)°; there were 17 cases in group A and 19 cases in group B with no significant difference in gender and age between 2 groups (P>0.05). The preoperative C2-C7 Cobb angle in group B was significantly lower than that in group A (t=–2.150, P=0.039), while there was no significant difference in preoperative C2-C7 SVA between 2 groups (t=0.206, P=0.838). At last follow-up, except for the curvature loss after operation in group B was significantly lower than that in group A (t=–2.723, P=0.010), there was no significant difference in the other indicators between 2 groups (P>0.05).
Conclusion
Preoperative larger T1S (T1S>19°) in MRI had a larger preoperative lordosis angle, but more postoperative physiological curvature was lost; preoperative T1S in MRI can not predict postoperative curvature loss, but preoperative larger T1S may be more prone to kyphosis.
Objective To evaluate the cl inical outcomes and values of anterior segmental decompression and double-plate fixation (ASDDF) for treatment of ski p cervical spondylotic myelopathy (SCSM). Methods Between June 2005 and June 2008, 17 patients with SCSM were treated with ASDDF. There were 10 males and 7 females with an average age of 58.8 years (range, 41-74 years) and an average disease duration of 9.7 months (range, 6-39 months). According to JapaneseOrthopaedic Association (JOA) score system, 2 patients were rated as extreme severe condition, 7 as severe, 7 as moderate, and 1 as mild. MRI images showed 42 affected cervical disc levels, including 26 disc levels with high-intensity intramedullary lesions on T2, 4 with low-intensity intramedullary lesions on T1, and 12 with significant cord compression but no signal change; according to Nagata classification scale, there were 5 abnormal segments at class I, 21 at class II, and 16 at class III. The rate of fusion, the Cobb angle, and the range of motion (ROM) of the cervical spine were measured preoperatively and postoperatively by the X-ray examinations. The improvement of the neurological function was evaluated by the JOA score. Results The average time of follow-up was 28.6 months (range, 24-58 months). After operation, dysphagia occurred in 2 cases (symptom rel ief after 1 month), hoarseness in 1 case (symptom rel ief after 3 months of methylcobalamin treatment), and degeneration of adjacent segments without symptom in 3 cases. The X-ray films showed the fusion rate of 100% at 12 months after operation without displacement, resorption or collapse of bone graft, and without breakage or loosening of plate and screw. The Cobb angles were (13.3 ± 10.4)° preoperatively, (15.8 ± 10.8)° immediately postoperatively, and (15.4 ± 11.4)° at last follow-up; the ROM of the cervical spine were (41.3 ± 17.4)° preoperatively and (23.8 ± 18.8)° at last follow-up; and the JOA scores were 8.2 ± 2.9 preoperatively, 13.7 ± 3.0 at 12 months postoperatively, and 13.9 ± 2.8 at last follow-up. All indexes showed significant differences between before operation and after operation (P lt; 0.05). The results of JOA scores were excellent in 8 cases, good in 6, fair in 2, and poor in 1 with an average improvement rate of 66.8% (range, 14%-88%) for the neurological function. Conclusion Adequate decompression, high rate of fusion, sol id mechanical stabil ity, improvement of total cervical lordosis,and the neurological function can be achieved through ASDDF for treatment of SCSM.
ObjectiveTo explore the feasibility of posterior debridement, decompression, bone grafting, and fixation in treatment of thoracic spinal tuberculosis with myelopathy, and investigate the effects of surgical timing on postoperative outcomes.MethodsThe clinical data of 26 patients with thoracic spinal tuberculosis with myelopathy between August 2012 and October 2015 was retrospectively analyzed. All patients underwent posterior unilateral transpedicular debridement, decompression, bone grafting, and fixation and were divided into two groups according to surgical timing. Group A included 11 patients with neurological dysfunction lasting less than 3 months; group B included 15 patients with neurological dysfunction lasting more than 3 months. No significant difference was found between the two groups in gender, age, involved segments, preoperative erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), Cobb angle of involved segment, and preoperative American Spinal Injury Association (ASIA) classification (P>0.05). The operation time, intraoperative blood loss, hospitalization stay, perioperative complications, and bone fusion time were recorded and compared between the two groups. The change of pre- and post-operative Cobb angle of involved segments was calculated. Neurological function was assessed according to ASIA classification.ResultsAll patients were followed up 25-60 months (mean, 41.6 months). No cerebrospinal fluid leakage occurred intra- and post-operation. The hospitalization stay and perioperative complications in group A were significantly less than those of group B (P<0.05). There was no significant difference in operation time, intraoperative blood loss, and bone fusion time between the two groups (P>0.05). At last follow-up, there was no significant difference in ESR and CRP between groups A and B (P>0.05), but they were all significantly lower than those before operation (P<0.05). In group A, 1 patient with T6, 7 tuberculosis developed sinus that healed after dressing; the implants were removed at 20 months with bony union and no recurrence was found after 36 months of follow-up. One patient with T4, 5 tuberculosis in group B underwent revision because of recurrence and distal junctional kyphosis of the thoracic spine at 26 months after operation. There was no internal fixation-related complications or tuberculosis recurrence occurred in the remaining patients. At last follow-up, the Cobb angles in the two groups significantly improved compared with those before operation (P<0.05), but there was no significant difference in the Cobb angle and correction degree between the two groups (P>0.05). At last follow-up, the ASIA classification of spinal cord function was grade C in 1 case and grade E in 10 cases in group A, and grade D in 2 cases and grade E in 13 cases in group B; the ASIA classification results in the two groups significantly improved compared with preoperative ones (P<0.05), but no significant difference was found between the two groups (Z=–0.234, P=1.000).ConclusionPosterior unilateral transpedicular debridement, decompression, bone grafting, and fixation is effective in treatment of thoracic spinal tuberculosis with myelopathy. Early surgery can reduce the hospitalization stays and incidence of perioperative complications.
Objective To evaluate the application of surgical strategies for the treatment of cervical ossification of the posterior longitudinal ligament (OPLL) involving the C2 segment. Methods The literature about the surgery for cervical OPLL involving C2 segment was reviewed, and the indications, advantages, and disadvantages of surgery were summarized. Results For cervical OPLL involving the C2 segments, laminectomy is suitable for patients with OPLL involving multiple segments, often combined with screw fixation, and has the advantages of adequate decompression and restoration of cervical curvature, with the disadvantages of loss of cervical fixed segmental mobility. Canal-expansive laminoplasty is suitable for patients with positive K-line and has the advantages of simple operation and preservation of cervical segmental mobility, and the disadvantages include progression of ossification, axial symptoms, and fracture of the portal axis. Dome-like laminoplasty is suitable for patients without kyphosis/cervical instability and with negative R-line, and can reduce the occurrence of axial symptoms, with the disadvantage of limited decompression. The Shelter technique is suitable for patients with single/double segments and canal encroachment >50% and allows for direct decompression, but is technically demanding and involves risk of dural tear and nerve injury. Double-dome laminoplasty is suitable for patients without kyphosis/cervical instability. Its advantages are the reduction of damage to the cervical semispinal muscles and attachment points and maintenance of cervical curvature, but there is progress in postoperative ossification. Conclusion OPLL involving the C2 segment is a complex subtype of cervical OPLL, which is mainly treated through posterior surgery. However, the degree of spinal cord floatation is limited, and with the progress of ossification, the long-term effectiveness is poor. More research is needed to address the etiology of OPLL and to establish a systematic treatment strategy for cervical OPLL involving the C2 segment.
Objective To evaluate the cl inical appl ication value and short-term results of Vertex rod-screw system in cervical expansive open-door laminoplasty. Methods Between February 2008 and January 2010, 28 patients underwent Vertex rod-screw system fixation in cervical expansive open-door laminoplasty, including 15 cases of cervical spondylotic myelopathy, 5 cases of ossification of posterior longitudinal l igament，and 8 cases of cervical spondylosis with spinal stenosis. There were 16 males and 12 females, aged 42-77 years (mean, 61.3 years). The disease duration was 2 months to 11 years. The decompression range of cervical spine was from C3 to C7. The operation time, blood loss, Japanese Orthopedic Association (JOA) scores, and incidence of axial symptom were recorded. Pre- and postoperative curvature angles were demonstrated by the cross angle between posterior vertebral body margins of C2 and C7 on cervical X-ray films. The angle of the opened laminae was measured on CT scan at last follow-up. Results The operation time was (142.5 ± 22.8) minutes, and the blood loss was (288.2 ± 55.1) mL. All incisions healed by first intention. All patients were followed up 14-25 months (mean, 22 months). CT showed that no reclosed open-laminae or loosening and breakage of rod-screw system occurred at 1 week and 1 year after operation. The axial bony fusion rate was 89.3% (25/28). The improvement rate of JOA scores at 1 week after operation (29.5% ± 15.0%) was significantly smaller than that at 1 year after operation (64.9% ± 28.1%) (t=0.810, P=0.000). No case presented with C5 nerve root palsy. The cervical curvature angle was (24.29 ± 5.04)° before operation, was (23.89 ± 3.57)° at 1 week, and was (23.41 ± 3.35)° at 1 year after operation, showing no significant difference between pre- and postoperative angles (P gt;0.05). The angle of the opened laminae was (27.90 ± 4.74)° at 1 week after operation, and was (28.07 ± 4.21)° at 1 year after operation, showing no significant difference (P gt; 0.05). Conclusion Vertex rod-screw system in cervical expansive opendoor laminoplasty is effective in preventing reclosed open-laminae, which can reduce the loss of cervical curvature angle.
ObjectiveTo investigate the effect of prophylactic C4, 5 foraminal dilatation in posterior cervical open-door surgery on postoperative C5 nerve root palsy syndrome.MethodsThe clinical data of patients with cervical spondylotic myelopathy (cervical spinal cord compression segments were more than 3) who met the selection criteria between March 2016 and March 2019 were retrospectively analyzed. Among them, 40 patients underwent prophylactic C4, 5 foraminal dilatation in posterior cervical open-door surgery (observation group) and 40 patients underwent simple posterior cervical open-door surgery (control group). There was no significant difference between the two groups (P>0.05) in gender, age, disease duration, Nurick grade of spinal cord symptoms, and preoperative diameter of C4, 5 intervertebral foramen, Japanese Orthopaedic Association (JOA) score, and visual analogue scale (VAS) score. The occurrence of C5 nerve root paralysis syndrome was recorded and compared between the two groups, including incidence, paralysis time, recovery time, and spinal cord drift. VAS and JOA scores were used to evaluate the improvement of pain and function before operation and at 12 months after operation.ResultsThe incisions of the two groups healed by first intention, and there was no early postoperative complications such as cerebrospinal fluid leakage. Patients of both groups were followed up 12-23 months, with an average of 17.97 months. C5 nerve root paralysis syndrome occurred in 8 cases in the observation group (3 cases on the right and 5 cases on the left) and 2 cases in the control group (both on the right). There was significant difference of the incidence (20% vs. 5%) between the two groups (χ2=4.114, P=0.043). Except for 1 case in the observation group who developed C5 nerve root palsy syndrome at 5 days after operation, the rest patients all developed at 1 day after operation; the recovery time of the observation group and the control group were (3.87±2.85) months and (2.50±0.70) months respectively, showing no significant difference between the two groups (t=–0.649, P=0.104). At 12 months after operation, the JOA score and VAS score of cervical spine in the two groups significantly improved when compared with those before operation (P<0.05); there was no significant difference in the difference of the cervical spine JOA score and VAS score between at 12 months after operation and before operation and the degree of spinal cord drift between the two groups (P>0.05).ConclusionProphylactic C4, 5 foraminal dilatation can not effectively prevent and reduce the occurrence of postoperative C5 root palsy, on the contrary, it may increase its incidence, so the clinical application of this procedure requires caution.
ObjectiveTo evaluate the effectiveness of cervical disc replacement for cervical myelopathy. MethodsBetween October 2006 and October 2008, 20 patients (26 segments) with cervical myelopathy underwent single-level (14 segments) or bi-level (6 segments) cervical disc replacement. There were 8 males and 12 females with an average age of 46 years (range, 26-65 years). The disease duration ranged 2-18 months (mean, 7 months). The effectiveness was evaluated using visual analogue scale (VAS) score, cervical range of motion (ROM), and the Odom et al. criteria. Heterotopic ossification (HO), osteophyte formation, and prosthesis loosening were observed. ResultsAll incisions healed by first intention, with no severe complication. Twenty patients were followed up 30-48 months (mean, 34 months). At 28 months after operation, according to Odom et al. criteria, the results were excellent in 17 cases and good in 3 cases. The VAS scores of the neck, shoulder, and upper limb were significantly improved when compared with preoperative scores (P lt; 0.05). At 30 months after operation, X-ray films showed that 20 replaced segments were mobile and ROM was (10.6 ± 4.5)°, showing no significant difference (P gt; 0.05) when compared with that of upper adjacent segment (10.8 ± 3.7)° and lower adjacent segment (7.5 ± 4.2)°. HO occurred in 10 cases (13 segments). No displacement, subsidence, or loosening occurred except 1 case of retrodisplacement of the prosthesis. ConclusionCervical disc replacement can obtain good effectiveness. It can maintain normal cervical ROM and physiological curvature. But it needs further long-term follow-up to evaluate the function and the influence on the adjacent segments.
Objective
To assess the mid-term effectiveness of anterior decompression and fusion with nano-hydroxyapatite/polyamide 66 (n-HA/PA66) cage in treatment of cervical spondylotic myelopathy.
Methods
A retrospective study was made on 48 patients with cervical spondylotic myelopathy who underwent anterior decompression and fusion with n-HA/PA66 cage between August 2008 and January 2010. There were 33 males and 15 females with an average age of 54.5 years (range, 42-72 years). The disease duration was 3-12 months (mean, 6 months). The affected segments included 35 cases of single segment (C3, 4 in 7, C4, 5 in 18, and C5, 6 in 10) and 13 cases of double segments (C3-5 in 7 and C4-6 in 6). Of 48 patients, 28 was diagnosed as having intervertebral disc protrusion, 12 as having ossification of posterior longitudinal ligament, and 8 as having vertebral osteophyte; 35 patients underwent single segmental anterior corpectomy and fusion, and 13 patients underwent single segmental anterior discectomy and fusion. The pre- and post-operative radiographs (cervical anteroposterior and lateral X-ray films and three-dimensional CT scans) were taken to measure the segmental height and lordosis angle. Brantigan et al assessment standard and visual analogue scale (VAS) and Japanese Orthopaedic Association (JOA) scores were used to evaluate the graft fusion and the improvement of clinical symptoms, respectively.
Results
All patients were followed up for 46 months on average (range, 36-54 months). No cage breaking, displacement, or sliding was found. At last follow-up, 36 cases were rated as Brantigan grade E, 10 cases as grade D, and 2 cases as grade C; the fusion rate was 96%. Both segmental height and lordosis angle were corrected significantly at immediate and 6 months after operation and last follow-up than those before operation (P lt; 0.05), but no significant difference was found among different time points after operation (P gt; 0.05). At last follow-up, the cage subsidence was (1.3 ± 1.0) mm. The VAS and JOA scores at 6 months after operation and last follow-up were significantly improved when compared with preoperative scores (P lt; 0.05), and the scores at last follow-up were superior to ones at 6 months after operation (P lt; 0.05).
Conclusion
The mid-term effectiveness of anterior decompression and fusion with the n-HA/PA66 cage in patients with cervical spondylotic myelopathy is satisfactory because it can effectively restore and maintain segmental height and lordosis angle and promote osseous fusion.
ObjectiveTo analyze the clinical outcome of anterior cervical discectomy and fusion using a Zero-profile interbody fusion and fixation device (Zero-P) for cervical spondylotic myelopathy.
MethodsBetween April 2011 and September 2013, 26 cases of cervical spondylotic myelopathy underwent anterior cervical discectomy and fusion with the Zero-P. Of 26 cases, 12 were male and 14 were female, aged 43-82 years (mean, 58.3 years). The disease duration was from 3 months to 10 years (mean, 5.9 years). The involved segments included C3,4 in 5 cases, C4,5 in 3 cases, C5,6 in 6 cases, and C6,7 in 12 cases. The clinical outcome was evaluated using visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, and Neck Disability Index (NDI) score before operation and after operation.
ResultsThe operations were successful and the operation time was 75-140 minutes (mean, 105 minutes); and blood loss was 20-150 mL (mean, 45 mL). There was no complications of infection, neural injury, esophageal fistula, prevertebral hematoma, or leakage of cerebrospinal. Dysphagia occurred in 1 case within 1 week after operation,and disappeared after 1 month. All patients were followed up for an average of 15.3 months (range, 12-18 months). The clinical symptoms were relieved after operation. During follow-up, no implant displacement or subsidence, screw breakage, and cervical instability were observed. At 3 and 12 months after operation, the VAS score and NDI reduced significantly (P<0.05); the JOA score increased significantly (P<0.05); and the intervertebral space height and the cervical Cobb angle improved significantly (P<0.05). But there was no significantly difference between at 3 and 12 months (P>0.05). According to JOA evaluation, the results were excellent in 14 cases, good in 10 cases, and fair in 2 cases, with an excellent and good rate of 92.3% at last follow-up.
ConclusionThe clinical outcome of anterior cervical discectomy and fusion using a Zero-P is satisfactory and reliable in the treatment of cervical spondylotic myelopathy. It can restore the cervical physiological curve and the intervertebral space height and decrease the incidence of postoperative dysphagia.
Objective To evaluate the cl inical effects of anterior segmental decompression and autograft fusion in treating multi-level cervical spondylotic myelopathy (CSM). Methods Between January 2007 and May 2009, 23 patients with multi-level CSM were treated with anterior segmental decompression, autograft fusion, and internal fixation. There were 16 males and 7 females with an average age of 58 years (range, 49-70 years). Consecutive 3 segments of C3,4, C4, 5, and C5, 6 involvedin 15 cases and C4, 5, C5, 6, and C6, 7 in 8 cases. All patients suffered sensory dysfunction in l imbs and trunk, hyperactivity of tendon reflexes of both lower extremities, walking with l imp, and weakening of hand grip. Cervical MRI showed degeneration and protrusion of intervertebral disc and compression of cervical cord. The disease duration was 6 to 28 months (12.5 months on average). Japanese Orthopaedic Association (JOA) score system was adopted for therapeutic efficacy evaluation. JOA scores were recorded preoperatively, 1 week, 3 months, and 12 months postoperatively. Results Dura tear occurred in 1 case and was treated by fill ing with gelatinsponge during operation; no cerebrospinal fluid leakage was observed after operation. All the incisions healed by first intention. All cases were followed up 12 to 24 months (15.1 months on average), and no vertebral artery injury or recurrent laryngeal nerve injury occurred. The nervous symptoms in all cases were improved significantly within 1 week after operation. Lower l imb muscle strength increased, upper l imb abnormal sensation disappeared, and l imb moved more agile. A 2-mm collapses of titanium mesh into upper terminal plate were found in 1 case and did not aggravated during followup.The other internal fixator was in appropriate situation, and the fusion rate was 100%. The JOA score increased from 9.1 ±0.3 preoperatively to 14.3 ± 0.4 at 12 months postoperatively with an improvement rate of 65.8% ± 0.2%, showing significant difference (P lt; 0.01). According to Odom evaluation scale, the results were excellent in 10 cases, good in 8 cases, fair in 4 cases, and poor in 1 case. Conclusion Anterior segmental decompression and autograft fusion is a recommendable technique for multi-level CSM, which can make full decompression, conserve the stabil ity of cervical cord, and has high fusion rate.
