Single door laminoplasty plus posterior fusion for posterior atlantoaxial dislocation with congenital malformation:A case report and review of literature

BACKGROUND Posterior atlantoaxial dislocation(PAD)is a rare type of upper cervical spine disease.We sought to describe a unreported case of old PAD with os odontoideum(OO)and atlas hypoplasia(AH)and our unique treatment approach consisting of C1 single door laminoplasty with C1-3 posterior fixation and fusion.CASE SUMMARY A 70-year-old male patient who suffered from progressive aggravating numbness and limb weakness for 4 years without trauma,was diagnosed with old PAD with OO and AH.The patient underwent closed reduction and C1 single door laminoplasty with C1-3 posterior fixation and fusion instead of C1 laminectomy with occipitocervical fusion.During the 3-year follow-up,he was able to walk by himself instead of using a wheelchair and with a±25°range of head rotation as well as a±10°range of flexion-extension.Three-year follow-up images showed satisfactory reduction and fusion.CONCLUSION C1 single door laminoplasty with cervical fusion in PAD combined with spinal cord compression could be a suitable and effective surgical option.Compared with laminectomy and occipitocervical fusion,it retains more cervical range of motion,has a smaller incision and provides an adequate bone grafting space for atlantoaxial fusion.

CLINICAL OBSERVATION ON AURICULAR ACUPUNCTURE COMBINED WITH LOCAL ANAESTHESIA IN CERVICAL LAMINOPLASTY FOR CERVICAL SPONDYLISIS

Auricular acupuncture combined with local anaesthesia in cervical larninoplasty was studied. The aim of the study was to observe the analgesic action of this anaesthesia and the effects on respiratory and circulatory function. 70 patients were included in the study. There were 55 male and 15 female patients, aged between 39 and 67 years old. The unilateral otopoints including Shenmen, cervical vertebrae, sympathetic, subcortex, external lung and kidney points were used. The sterilized filiform needle of 1 - 1. 5 cm were inserted into each otopoint and connected to 57 - 6 electrcrpulse stimulator being stimulated with continuous wave. Local infiltration anaesthesia was also used with 1 - 2 g/L Lignocaine. The results showed that all the patients were conscious, quiet and co-operative with doctors.The respiration, blood pressure and heart rate were all stable. Analgesie action was rather definite. All the patients recovered quickly after operation. We consider that this anaesthesia is a very simple and effective method for cervical laminoplasty.

Subdural fluid collection rather than meningitis contributes to hydrocephalus after cervical laminoplasty:A case report

BACKGROUND Hydrocephalus following dural tear after spinal surgery is rare.Although a few cases of obstructive hydrocephalus caused by subdural fluid collection and communicating hydrocephalus associated with meningitis have been reported,the mechanism remains uncertain.Herein we describe a patient complicated with hydrocephalus after cervical laminoplasty in whom subdural fluid collection in the cervical spine and posterior cranial fossa rather than chronic meningitis was the main mechanism.CASE SUMMARY A 45-year-old man underwent cervical laminoplasty for cervical spondylotic myelopathy at a local hospital.Ten days postoperatively,a high fever occurred and magnetic resonance imaging(MRI)showed cerebrospinal fluid(CSF)leakage.Pseudomeningocele liquid test showed high levels of protein and white blood cell(WBC)count with negative bacterial culture.The patient was treated with shortterm intravenous antibiotic and discharged with normal body temperature.The patient was uneventful during the first 8 mo follow-up although repeated MRI showed persistent pseudomeningocele.At the 9th mo postoperatively,the patient gradually presented with dizziness and headache accompanied by recurrent weakness of his left arm.Imaging examinations demonstrated hydrocephalus and a cystic lesion around the cervical spinal cord.CSF test from lumbar puncture indicated chronic meningitis.MRI on 1 d after pseudomeningocele drainage showed a significant decrease in the cystic volume,suggesting that the cystic lesion would be subdural fluid collection rather than adhesive arachnoiditis.After dural defect repair,the patient’s symptoms completely resolved and hydrocephalus gradually disappeared.CSF analysis at the 21-mo follow-up revealed significantly decreased protein level and WBC count.CONCLUSION Subdural fluid collection rather than meningitis contributes to the hydrocephalus formation after cervical laminoplasty.

Development and prospects of cervical laminoplasty

Cervical laminoplasty surgery is an alternative to laminectomy. It can increase the space of the spinal cord available by raising the lamina, and achieve the indirect decompression effect to treat cervical spondylosis. Various techniques of laminoplasty have since been developed after two prototype techniques: Hirabayashi's open-door laminoplasty and Kurokawa's double-door laminoplasty. Several studies report superior biomechanical stability of the cervical spine after laminoplasty compared with laminectomy. Recent development in laminoplasty is preservation of muscle attachment, which enabled dynamic and static stabilization of the cervical spine by neck extensor muscles. After treatment with new laminoplasty techniques with active postoperative neck muscle exercises, postoperative instability, kyphosis, axial neck pain, and loss of ROM become minimal. The development,complications and future trends of cervical laminoplasty are summarized below.

Effect of decompression range on decompression limit of cervical laminoplasty

Backgrounds:Cervical posterior decompression surgery is used to relieve ventral compression indirectly by incorporating a backward shift of the spinal cord, and this indirect decompression is bound to be limited. This study aimed to determine the decompression limit of posterior surgery and the effect of the decompression range.Methods:We retrospectively reviewed the data of 129 patients who underwent cervical open-door laminoplasty through 2008 to 2012 and were grouped as follows: C4-C7 ( n = 11), C3-C6 ( n = 61), C3-C7 ( n = 32), and C2-C7 ( n = 25). According to the relative location of spinal levels within a decompression range, the type of decompression at a given level was categorized as external decompression (ED;achieved at the levels located immediately external to the decompression range margin), internal decompression (ID;achieved at the levels located immediately internal to the decompression range margin), and central decompression (CD;achieved at the levels located in the center, far from the decompression range margin). The vertebral-cord distance (VCD) was used to evaluate the decompression limit. The C2-C7 angle and VCD on post-operative magnetic resonance images were analyzed and compared between groups. The relationship between VCD and decompression type was analyzed. Moreover, the relationship between the magnitude of the ventral compressive factor and the probability of post-operative residual compression at each level for different decompression ranges was studied. Results:There was no significant kyphosis in cervical curvature (>-5°), and there was no significant difference among the groups ( F = 2.091, P = 0.105). The VCD of a specific level depended on the decompression type of the level and followed this pattern: ED < ID < CD ( P < 0.05). The decompression type of a level was sometimes affected by the decompression range. For a given magnitude of the ventral compressive factor, the probability of residual compression was lower for the group with the larger VCD at this level. Conclusions:Our study suggests that the decompression range affected the decompression limit by changing the decompression type of a particular level. For a given cervical spinal level, the decompression limit significantly varied with decompression type as follows: ED < ID < CD. CD provided maximal decompression limit for a given level. A reasonable range of decompression could be determined based on the relationship between the magnitude of the ventral compressive factor and the decompression limits achieved by different decompression ranges.

Comparison of the anterior and posterior approach in treating four-level cervical spondylotic myelopathy

Background:The optimal surgical approach for four-level cervical spondylotic myelopathy remains controversial.The purpose of this study was to compare clinical and radiological outcomes and complications between the anterior and posterior approaches for four-level cervical spondylotic myelopathy.Methods:A total of 19 patients underwent anterior decompression and fusion and 25 patients underwent posterior laminoplasty and instrumentation in this study.Perioperative information,intraoperative blood loss,clinical and radiological outcomes,and complications were recorded.Japanese Orthopedic Association(JOA)score,36-item short form survey(SF-36)score and cervical alignment were assessed.Results:There were no significant differences in JOA scores between the anterior and posterior group preoperatively(11.6±1.6 vs.12.1±1.5),immediately postoperatively(14.4±1.1 vs.13.8±1.3),or at the last follow-up(14.6±1.0 vs.14.2±1.1)(P>0.05).The JOA scores significantly improved immediately postoperatively and at the last follow-up in both groups compared with their preoperative values.The recovery rate was significantly higher in the anterior group both immediately postoperatively and at the last follow-up.The SF-36 score was significantly higher in the anterior group at the last follow-up compared with the preoperative value(69.4 vs.61.7).Imaging revealed that there was no significant difference in the Cobb angle at C2-C7 between the two groups preoperatively(-2.0°±7.3°vs.-1.4°±7.5°).The Cobb angle significantly improved immediately postoperatively(12.3°±4.2°vs.9.2°±3.6°)and at the last follow-up(12.4°±3.5°vs.9.0°±2.6°)in both groups compared with their preoperative values(P=0.00).Three patients had temporary dysphagia in the anterior group and four patients had persistent axial symptoms in the posterior group.Conclusions:Both the anterior and posterior approaches were effective in treating four-level cervical spondylotic myelopathy in terms of neurological clinical outcomes and radiological features.However,the JOA score recovery rate and SF-36 score in the anterior group were significantly higher.Persistent axial pain could be a major concern when undertaking the posterior approach.