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Objective To investigate biomechanical differences of two posterior occipitocervical internal fixation techniques for treating basilar invagination with atlantoaxial dislocation (BI-AAD). Methods Intra-articular cage + posterior occipital plate+C2 pedicle screw (Cage+C2PS+OP), and intra-articular cage+C1 lateral mass screw+C2PS (Cage+C1LMS+C2PS) models were established based on occipitocervical CT data of the BI-AAD and clinical operation scheme, and the stability of atlantoaxial joint and stress distribution characteristics of C2 endplate and implanted instruments under different motion states were analyzed. Results Compared with the Cage+C1LMS+C2PS model, the atlantoaxial range of motion ( ROM) under flexion, extension, lateral bending and axial rotation in the Cage+C2PS+OP model were reduced by 5. 26% , 33. 33% , 43. 75% , -5. 56% , and stress peak of screw-rod fixation system were reduced by 47. 81% , 60. 90% , 48. 45% , 39. 14% , respectively. Under two internal fixation modes, stresses of C2 endplate and cage were mainly distributed on the compressive side during the motion, and both the screw-bone interface and the caudal side of screw subjected to large loading. Conclusions Two internal fixation methods could provide similar stability. However, the stress concentration of screw-rod system was more obvious and the possibility of screw loosening and fracture was greater under Cage+ C1LMS+C2PS fixation.
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Atlantoaxial dislocation (AAD) is a kind of life-threatening atlantoaxial structural instability and a series of neurological dysfunction caused by common multidisciplinary diseases. The operation risk is extremely high because it is adjacent to the medulla oblongata and the location is deep. With the increase of the number of operations in the upper cervical region, postoperative complications such as failure of internal fixation, non fusion of bone graft and poor prognosis gradually increase.Incomplete primary operation, non fusion of bone graft, infection and congenital malformation are the potential causes. In addition, considering the objective factors such as previous graft, scar formation and anatomical marks changes, revision surgery is further difficult. However, there is currently no standard or single effective revision surgery method. Simple anterior surgery is an ideal choice in theory, but it has high risk and high empirical requirements for the operator;simple posterior surgery has some defects, such as insufficient reduction and decompression;anterior decompression combined with posterior fixation fusion is a more reasonable surgical procedure, but many problems such as posterior structural integrity and multilevel fusion need to be considered.This article reviews the causes and strategies of AAD revision surgery.
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Humans , Atlanto-Axial Joint/surgery , Joint Dislocations/surgery , Joint Instability/surgery , Reoperation/adverse effects , Spinal Fusion/methods , Treatment OutcomeABSTRACT
Objective To investigate the feasibility of absorbable magnesium alloy screws in atlantoaxial dislocation fixation. Methods Four kinds of screws with triangular, rectangular, trapezoidal and zigzag thread were designed with WE43 magnesium alloy. The finite element simulation analyses were performed on the screw- polyurethane model and atlantoaxial fixation system model. The stress and displacement distributions on the models were obtained. Results The pull-out force simulations were carried out on four kinds of magnesium alloy screws according to ASTM F543 standard specification. The stresses of screws with triangular, rectangular, trapezoidal and zigzag thread were 146.20, 185.22,194.98, 264.55 MPa, respectively. The pull-out strength of the screw with triangular thread was the largest, and the peak stress was the smallest. The magnesium alloy screw with triangular thread used for atlantoaxial fixation could meet the strength requirements of flexion/extension, rotation and bending of the neck. The peak stress of the screw was reduced by 17.16 MPa after adding hydroxyapatite (HA) coating on the surface, and the stress on the screw was within the range of bonding strength between coating and magnesium alloy substrate. Conclusions Under the same loading condition, the screw with triangular thread has good stability and the best pull-out force performance. After heat treatment, the strength of magnesium alloy screw with triangular thread meets the load-bearing requirements for atlantoaxial dislocation fixation. HA coating on screw surface can optimize mechanical properties of the screw, and there exits good bonding strength between the coating and the screw.
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BACKGROUND: In patients undergoing transoral atlantoaxial reduction and internal fixation, anterior atlantoaxial plate placement, soft tissue swelling and other factors may affect oropharyngeal space. Up to now no anatomical factors regarding dysphagia or dyspnea after anterior approach for atlantoaxial dislocation have been reported. OBJECTIVE: To observe the spatial changes of oropharyngeal airway after atlantoaxial dislocation and internal fixation with transoral atlantoaxial reduction screw-rod system and analyze the related influencing factors. METHODS: Sixty-six patients with atlantoaxial dislocation undergoing transoral atlantoaxial reduction screw-rod system surgery were retrospectively included from January 2012 to December 2016 in the General Hospital of Southern Theater Command. There were 38 males and 28 females aged from 11 to 71 years. All patients signed the informed consent. This study was approved by the Hospital Ethics Committee. The narrowest oropharyngeal airway space, thickness of soft tissue before C2 vertebra, anterior atlantodental interval, O-C2 angle, and C2-C6 angle were measured in the neutral position before and after surgery. Changes of postoperative data and their effects on the narrowest airway distance in oropharynx were analyzed. RESULTS AND CONCLUSION: (1) The narrowest airway distance in oropharynx, anterior atlantodental interval and C2-C6 angle were significantly decreased after surgery compared with that before surgery (P <0.001). Thickness of soft tissue before C2 vertebra and O-C2 angle increased significantly after surgery compared with that before surgery (P < 0.001). (2) In the multiple regression analysis, the change in the anterior atlantodental interval (0=7.070) and thickness of soft tissue before C2 vertebra 03=0.387) were significant variables related to the change in the narrowest airway distance in oropharynx. On the contrary, there was no significant correlation with the O-C2 angle. (3) It is indicated that reduction of atlantoaxial dislocation and the thickness of soft tissue before C2 vertebrae have negative effect on the oropharyngeal airway space. Therefore, reduction of atlantoaxial dislocation during transoral reduction screw-rod surgery may cause postoperative dysphagia despite maintenance of the O-C2 angle.
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BACKGROUND: Atlantoaxial dislocation often needs surgery for reduction, and posterior screw-rod fixation fusion is the most commonly used surgery. However, the current screw-rod fixation system often increases the reduction effect by increasing the degree of curvature of connecting rod, causing great difficulty of placing rod, which increases the probability of spinal cord injury. OBJECTIVE: To evaluate the preliminary results of fulcrum screws for atlantoaxial dislocation. METHODS: From January 2017 to December 2018,11 patients with atlantoaxial dislocation were selected from General Hospital of Southern Theater Command of PLA, including 4 males and 7 females, at the age of 8-51 years. All patients were treated with posterior screw-rod fixation fusion: Conventional posterior cervical screws were implanted on both sides of the atlas and pivot screws were implanted on both sides of the axis. Atlantodental interval and Japanese Orthopaedic Association scores were recorded before and after operation. Patients were followed up and underwent X-ray and CT to estimate reduction, fixation and bone graft fusion. This study was approved by the Ethics Committee of General Hospital of Southern Theater Command of PLA. RESULTS AND CONCLUSION: (1) Eleven patients underwent operations successfully without vertebral artery or spinal nerve injury. (2) All patients were followed up for 3-12 months, with an average of 6 months. The symptoms of neck pain and neurological dysfunction were improved in varying degrees. All patients obtained atlantoaxial bone fusion, with an average fusion time of 6 months. (3) At postoperative 1 week, X-ray and CT images showed that atlantoaxial reduction was satisfactory and internal fixation was in good position. (4) Atlantodental interval reduced from preoperatively (6.8±1.5) mm to postoperatively (2.4±0.9) mm (f=17.854, P=0.000). Japanese Orthopaedic Association score increased from preoperatively (14.1±1.3) to postoperatively (15.9±0.9) (f=-10, P=0.000). (5) No complication occurred during follow-up, without recurrence or dislocation. (6) These results showed that using fulcrum screw in posterior screw-rod fixation fusion has an effective reduction for treating atlantoaxial dislocation and its preliminary clinical effects are satisfactory.
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Objective: To investigate reliability and short-term effectiveness of axis laminar screws for reducible atlantoaxial dislocation (RAAD). Methods: A clinical data of 41 patients with RAAD who were admitted between February 2013 and February 2018 and met the inclusion criteria was retrospectively analyzed. The atlases in all patients were fixated by lateral mass screws, and the axes were fixed by laminar screws in 13 cases (LS group) and by pedicle screws in 28 cases (PS group). There was no significant difference in gender, age, and preoperative Japanese Orthopedic Association (JOA) score between the two groups ( P>0.05). The effectiveness was estimated by post-operative JOA score; and the accuracy of the axis screw, atlantoaxial bone graft fusion, and the fixation stability were examined by X-ray film and CT. Results: All incisions healed by first intention. All patients were followed up 12-17 months (mean, 13.8 months) in LS group and 12-20 months (mean 14.1 months) in PS group, and the difference in follow-up time was not significant ( Z=-0.704, P=0.482). At last follow-up, JOA scores were 13.9±1.6 in LS group and 14.3±1.8 in PS group, which significantly improved when compared with the pre-operative scores in the two groups ( t=-9.033, P=0.000; t=-15.835, P=0.000); while no significant difference was found between the two groups ( t=-0.630, P=0.532). Twenty-five screws of 26 screws in LS group and 54 screws of 56 screws in PS group were implanted accurately, with no significant difference in the accuracy of the axis screw between the two groups ( Z=-0.061, P=0.951). All patients obtained atlantoaxial bone graft fusion, except 1 case in PS group. There was no significant difference in the atlantoaxial bone graft fusion between the two groups ( Z=-0.681, P=0.496). Conclusion: For RAAD, Axis laminar screws can maintain the atlantoaxial primary stability and had a good short-term effectiveness. So, it could be an alternative and reliable technique for axis screw.
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OBJECTIVE@#To explore and compare the safety depths of perpendicular and oblique acupuncture at Yamen (GV 15) in patients with atlantoaxial dislocation (AAD) and healthy volunteers.@*METHODS@#One bundred and seventy-seven patients with atlantoaxial dislocation were selected as an AAD group, and 207 patients without atlantoaxial dislocation and with normal anatomical structure were selected as a normal group. All participants were moderately sized. The MRI scanning of the cervical vertebra was performed, and the safety depth of perpendicular and oblique acupuncture at Yamen (GV 15) was calculated on the sagittal image.@*RESULTS@#In the AAD group, the safety depth of men was (45.33±5.17) mm for perpendicular acupuncture and (48.58±4.41) mm for oblique acupuncture; the safety depth of women was (44.17±7.80) mm for perpendicular acupuncture and (47.49±7.32) mm for oblique acupuncture. In the normal group, the safety depth of men was (47.72±5.06) mm for perpendicular acupuncture and (42.69±5.53) mm for oblique acupuncture; the safety depth of women was (44.63±5.85) mm for perpendicular acupuncture and (39.88±6.18) mm for oblique acupuncture. The safety depth of men and women for oblique acupuncture was longer than that for perpendicular acupuncture in the AAD group (0.05); the safety depth of perpendicular and oblique acupuncture for men was longer than that for women in the normal group (0.05), while the safety depth of oblique acupuncture in the AAD group was longer than that in the normal group (<0.01).@*CONCLUSION@#The safe depth of acupuncture at Yamen (GV 15) has significantly changed under AAD, so during the clinical acupuncture the needle insertion should be less than its safe depth.
Subject(s)
Female , Humans , Male , Acupuncture Points , Acupuncture Therapy , Cervical Vertebrae , Joint Dislocations , Therapeutics , Neck Injuries , Therapeutics , NeedlesABSTRACT
Objective: To evaluate the clinical result of atlantoaxial reduction and fixation guided by the intraoperative CT.Methods: Sixteen cases were retrospectively studied, including seven males and nine females, with the mean age of 49.9 years.Twelve cases were diagnosed as chronic atlantoaxial instability or dislocation, while four cases as acute odontoid fracture and dislocation.Among the sixteen cases, fourteen underwent atlantoaxial fusion, while two underwent temporary atlantoaxial fixation without fusion.The intraoperative CT was used in the setting of: 1.Evaluating the atlantoaxial reduction before the screw insertion;2.Guiding the C1 and C2 pedicle drilling (two cases using additional three-dimensional printing drilling template);3.Evaluating the position of the screws and reduction after the atlantoaxial fixation.In addition, three-dimensional drilling template combined with intraoperative CT was used in two cases.CT scanning frequency was calculated.To evaluate the accuracy rate of screw fixation under the intraoperative CT, 19 cases without the intraoperative CT were studied as the control group.Results: Averaged CT scanning frequency was 1.4 times (Once in eleven cases, twice in four and three times in one).Among the sixteen cases, mal-positioned C1 screws were found and revised in two cases.No spinal cord injury or vertebral artery injury occurred.The follow-up ranged from three to ten months, with the mean of 6.7 months.Fourteen cases achieved solid osseous fusion, and two with temporary fixation had odontoid fracture union.Anatomic reduction was achieved in all the cases.Eleven cases with preoperative myelopathy had postoperative improvement and their mean JOA scores improved from 12.1 to 14.4.To the last follow-up, no hardware complications were found including screw broken, rod broken or fixation loosening.All the screws of intraoperative CT group had good positions.For 19 cases of the control group, there were two cases of mal-positioned screws (10.5%).Conclusion: Advantages of atlantoaxial reduction and fixation guided by the intraoperative CT included: improving the accuracy of the atlantoaxial screws, exactly evaluating the reduction of the atlantoaxial joint, immediately discovering the mal-positioned screws and avoiding the revision surgery.A good clinical result was found in the preliminary study.
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Objective The study was to investigate the value of deduction and application of anterior compression index in evaluation of atlantoaxial dislocation and restoration. Method Twenty-eight cases of the control group and 28 cases of atlantoaxial dislocation treated with posterior restoration and screw-rod internal fixation technique before and af?ter surgery were recruited in this study and their data was retrospectively analyzed. All of the people underwent sagittal computerized tomography scan films. The anterior compression index was measured in all cases. Results The mean value of anterior compression index of the control group was 87.86±24.98. The mean value of anterior compression index of the preoperative patients was 230.44 ± 97.60 and the mean value of the postoperative patients was 106.27 ± 73.53. There was significant difference in those two parameters between the preoperative patients and the controls(t=-7.50,P<0.0001). There was no significant difference between the postoperative patients and the control group (t=-1.26, P=0.2171). Anteri?or compression index were significantly lower after surgical operation (t=10.35, compared with before, P<0.0001). Con?clusion Anterior compression index can be an excellent measurement tool for the assessment of relationship of atlas and axis in atlantoaxial dislocation patients before and after posterior restoration operation.
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STUDY DESIGN: Four patients had C2-3 vertebral fusion and radiologically demonstrated cord compression at C3-4 level related to disc bulge with or without association of osteophytes and C1-2 posterior facetal dislocation. The outcome of treatment by atlantoaxial and subaxial facetal fixation is discussed. PURPOSE: The article evaluates the significance of atlantoaxial facetal instability in cases having C2-3 vertebral fusion and cord compression at the level of C3-4 disc. OVERVIEW OF LITERATURE: C2-3 vertebral fusions are frequently encountered in association with basilar invagination and chornic atlantoaxial dislocations. Even when basilar invagination and atlantoaxial dislocation are not identified by conventional parameters, atlantoaxial instability can be the nodal point of pathogenesis in cases with C2-3 vertebral fusion. METHODS: Between June 2013 and November 2014 four patients having C2-3 fusion presented with progressive symptoms of myelopathy that were related to cord compression at the level opposite the C3-4 disc space. Further investigations revealed C1-2 posterior facetal dislocation. RESULTS: All patients were males. Ages ranged from 18 to 50 years (average, 36 years). All patients were treated by atlantoaxial facetal plate and screw, and subaxial single or multi-segmental transarticular screw fixation. Follow-up (average, 15 months) using a recently described clinical grading system and the Japanese Orthopaedic Association scoring system confirmed marked improvement of symptoms. CONCLUSIONS: Identification and treatment of atlantoaxial facetal instability may be crucial for a successful outcome in cases having C2-3 fusion and high cervical (C3-4) disc related cord compression.
Subject(s)
Humans , Male , Asian People , Joint Dislocations , Follow-Up Studies , Osteophyte , Spinal Cord DiseasesABSTRACT
STUDY DESIGN: Four patients had C2-3 vertebral fusion and radiologically demonstrated cord compression at C3-4 level related to disc bulge with or without association of osteophytes and C1-2 posterior facetal dislocation. The outcome of treatment by atlantoaxial and subaxial facetal fixation is discussed. PURPOSE: The article evaluates the significance of atlantoaxial facetal instability in cases having C2-3 vertebral fusion and cord compression at the level of C3-4 disc. OVERVIEW OF LITERATURE: C2-3 vertebral fusions are frequently encountered in association with basilar invagination and chornic atlantoaxial dislocations. Even when basilar invagination and atlantoaxial dislocation are not identified by conventional parameters, atlantoaxial instability can be the nodal point of pathogenesis in cases with C2-3 vertebral fusion. METHODS: Between June 2013 and November 2014 four patients having C2-3 fusion presented with progressive symptoms of myelopathy that were related to cord compression at the level opposite the C3-4 disc space. Further investigations revealed C1-2 posterior facetal dislocation. RESULTS: All patients were males. Ages ranged from 18 to 50 years (average, 36 years). All patients were treated by atlantoaxial facetal plate and screw, and subaxial single or multi-segmental transarticular screw fixation. Follow-up (average, 15 months) using a recently described clinical grading system and the Japanese Orthopaedic Association scoring system confirmed marked improvement of symptoms. CONCLUSIONS: Identification and treatment of atlantoaxial facetal instability may be crucial for a successful outcome in cases having C2-3 fusion and high cervical (C3-4) disc related cord compression.
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Humans , Male , Asian People , Joint Dislocations , Follow-Up Studies , Osteophyte , Spinal Cord DiseasesABSTRACT
It is a well-know fact that type 2 odontoid fractures frequently go into nonunion. If left untreated, patients may develop irreducible atlantoaxial dislocation (AAD). We describe the surgical management of two patients with neglected odontoid fractures and irreducible AAD treated with single stage anterior release followed by posterior instrumented fusion. Both patients presented with history of neglected trauma and progressive myelopathy. Traction under anesthesia failed to achieve reduction of AAD. Anterior release was done by trans-oral approach in one patient and retrophayngeal approach in the other. Posterior fixation was performed with transarticular screws in both the patients. Both patients had full neurological recovery and demonstrated fusion at follow-up. Anterior release followed by posterior instrumented correction may be an effective alternative to the traditional means of treating irreducible dislocations associated with neglected odontoid fractures.
Subject(s)
Humans , Anesthesia , Atlanto-Axial Joint , Joint Dislocations , Follow-Up Studies , Odontoid Process , Spinal Cord Diseases , TractionABSTRACT
<p><b>OBJECTIVE</b>To retrospectively analyze the surgical methods and its clinical effects and explore a clinical classification and treatment strategy for atlantoaxial dislocation(AAD).</p><p><b>METHODS</b>The clinical data of 89 patients with atlantoaxial dislocation were analyzed from September 2005 to September 2013. There were 49 males and 40 females, aged from 13 to 67 years with an average of 48.1 years. According to the reductive effects with preoperative cervical dynamic radiograph and high weight skeletal traction under general anesthesia, the dislocations were classified into three types:easy reduction type, hard reduction type and irreducible type. The patients with easy reduction type were treated with posterior screw rod internal fixation after manual reduction, while the patients with hard reduction type were treated with posterior screw rod fixation after high weight skeletal traction reduction under general anesthesia. The patients with irreducible type were treated with transoral atlantoaxial joint release or depression and posterior internal fixation and fusion. According to JOA scores to evaluate the neurological status and treatment outcome.</p><p><b>RESULTS</b>Thirty patients were classified as easy reduction type, 55 patients as hard reduction type, and 4 patients as irreducible type. The preoperative JOA score was 8.2±3.1 on average, while the postoperative score was 14.2±2.4. The improvement rate was 40.1% to 82.5% with an average of 62.5%. Eighty nine patients were followed up from 6 to 37 months with a mean of 17.3 months. Eighty two cases obtained anatomical reduction and 85 cases obtained bony fusion. One case complicated with hyponatremia after operation and 1 case combined with Guillain-Barre syndrome, 4 cases complicated with delayed union wounds, 1 case died of for respiratory failure 2 years after operation. No wound infections were found in the patients approach for transoral operation.</p><p><b>CONCLUSIONS</b>According to the cervical dynamic radiograph and high weight skeletal traction under general anesthesia to classify for atlantoaxial dislocation, and adopting well strategies to treat the patients, can achieve satisfactory effects.</p>
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<p><b>OBJECTIVE</b>To explore the clinical effects of surgical treatment with cable dragged reduction and cantilever beam internal fixation by posterior approach for odontoid fracture associated with atlantoaxial dislocation.</p><p><b>METHODS</b>The clinical data of 12 patients with odontoid fracture associated with atlantoaxial dislocation from January 2008 to December 2013 were retrospectively analyzed. There were 8 males and 4 females, ranging in age from 21 to 53 years with an average of 37.2 years. Eleven cases were fresh fracture and 1 case was old fracture, all patients complicated with atlantoaxial anterior dislocation. According to Anderson-D' Alonzo typing method modified by Grauer, 3 cases were type IIA, 5 cases were type IIB, 3 cases were type IIC, and 1 case was type IIIA. All patients underwent surgical treatment with cable dragged reduction and cantilever beam internal fixation by posterior approach. JOA score and ADI method were respectively used to evaluate the nerve function and reductive condition of atlantoaxial dislocation.</p><p><b>RESULTS</b>All patients were followed up from 6 months to 2 years with an average of 1 year and 3 months. At 1 week, 6 months after operation, and final follow up, JOA scores were 13.2±1.3, 13.5±1.4, 14.3±1.5, respectively, and these data were obviously better than that of preoperative 8.3±1.4(<0.05). Postoperative X rays and CT showed satisfactory reduction of atlantoaxial dislocation. At 1 week, 6 months after operation, and final follow up, ADI were (2.2±0.4), (2.4±0.6), (2.3±0.5) mm, respectively, and these data were obviously better than that of preoperative.(5.8±1.2) mm(<0.05). All screws and cables had good location without looseness and breakage, and bone graft got fusion.</p><p><b>CONCLUSIONS</b>Surgical treatment with cable dragged reduction and cantilever beam internal fixation by posterior approach for odontoid fracture associated with atlantoaxial dislocation is a good method, with advantage of firm fixation and high safety. It could obtain good clinical effects.</p>
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OBJECTIVES: The transoral atlantoaxial reduction plate system treats irreducible atlantoaxial dislocation from transoral atlantoaxial reduction plate-I to transoral atlantoaxial reduction plate-III. However, this system has demonstrated problems associated with screw loosening, atlantoaxial fixation and concealed or manifest neurovascular injuries. This study sought to design a set of individualized templates to improve the accuracy of anterior C2 screw placement in the transoral atlantoaxial reduction plate-IV procedure. METHODS: A set of individualized templates was designed according to thin-slice computed tomography data obtained from 10 human cadavers. The templates contained cubic modules and drill guides to facilitate transoral atlantoaxial reduction plate positioning and anterior C2 screw placement. We performed 2 stages of cadaveric experiments with 2 cadavers in stage one and 8 in stage two. Finally, guided C2 screw placement was evaluated by reading postoperative computed tomography images and comparing the planned and inserted screw trajectories. RESULTS: There were two cortical breaching screws in stage one and three in stage two, but only the cortical breaching screws in stage one were ranked critical. In stage two, the planned entry points and the transverse angles of the anterior C2 screws could be simulated, whereas the declination angles could not be simulated due to intraoperative blockage of the drill bit and screwdriver by the upper teeth. CONCLUSIONS: It was feasible to use individualized templates to guide transoral C2 screw placement. Thus, these drill templates combined with transoral atlantoaxial reduction plate-IV, may improve the accuracy of transoral C2 screw placement and reduce related neurovascular complications. .
Subject(s)
Adult , Humans , Atlanto-Axial Joint/injuries , Bone Screws , Cervical Vertebrae/surgery , Joint Dislocations/surgery , Orthopedic Procedures/instrumentation , Bone Plates , Cadaver , Equipment Design , Feasibility Studies , Imaging, Three-Dimensional , Internal Fixators , Medical Illustration , Orthopedic Procedures/methods , Reference Values , Reproducibility of Results , Tomography, X-Ray ComputedABSTRACT
We report a rare case of tuberculosis as a cause of secondary basilar impression. A 35-year-old man was admitted to our hospital complaining of severe neck pain and motor weakness on both sides (upper and lower limbs). CT and MRI demonstrated C1/C2 subluxation, basilar impression, and an abscess occupying the prevertebral space. We performed a single-stage operation, comprising anterior removal of the abscess, posterior fixation, and fusion. The patient was discharged five weeks after surgery without any neurologic deficits or complications. Only few reports have been published worldwide describing cases of tuberculosis as a cause of secondary basilar impression. Tuberculosis of the craniovertebral (CV) junction should be considered, especially in young patients with mid- to long-term histories of neck pain without clear origins, to allow for early intervention.
Subject(s)
Adult , Humans , Abscess , Early Intervention, Educational , Neck Pain , Neurologic Manifestations , Platybasia , TuberculosisABSTRACT
Craniovertebral junction (CVJ) tuberculosis is a rare disease, potentially causing severe instability and neurological deficits. The authors present a case of CVJ tuberculosis with atlantoaxial dislocation and retropharyngeal abscess in a 28-year-old man with neck pain and quadriparesis. Radiological evaluations showed a widespread extradural lesion around the clivus, C1, and C2. Two stage operations with transoral decompression and posterior occipitocervical fusion were performed. The pathological findings confirmed the diagnosis of tuberculosis. Treatment options in CVJ tuberculosis are controversial without well-defined guidelines. But radical operation (anterior decompression and posterior fusion and fixation) is necessary in patient with neurological deficit due to cord compression, extensive bone destruction, and instability or dislocation. The diagnosis and treatment options are discussed.
Subject(s)
Adult , Humans , Cranial Fossa, Posterior , Decompression , Diagnosis , Joint Dislocations , Neck Pain , Quadriplegia , Rare Diseases , Retropharyngeal Abscess , TuberculosisABSTRACT
Atlantoaxial rotatory dislocation (AARD) is an uncommon disorder of childhood in which clinical diagnosis is generally difficult and often made late. It is very rare in adults because of the unique biomechanical features of the atlantoaxial articulation. We report a case of post-traumatic AARD in an adult. Reduction was difficult to obtain by skull traction and gentle manipulation. Therefore, the patient was treated surgically by an open reduction, transpedicular screw fixation, and posterior C1-2 wiring with graft. The normal atlantoaxial relation was restored with disappearance of torticollis. Postoperatively, the patient remains neurologically intact and has radiographic documentation of fusion. Atlantoaxial transpedicular screw fixation can be one of the treatment options for the AARD.
Subject(s)
Adult , Humans , Diagnosis , Joint Dislocations , Skull , Torticollis , Traction , TransplantsABSTRACT
[Objective]To discuss the causes and preventive measures of early complications after using Vertes technique in treating dens axis fracture with atlantoaxial dislocation.[Method]Eighteen cases performed Vertex technique were included in this study.The early complications(postoperative or at surgery) included vertebral artery injury(2 cases),logagnosia(1 case),anopsia(1 case),hematorrhea(1 case) and wrong instrumentation(1 case).The causes of these complications and how to prevent were analyzed.[Result]All these complications were treated in time,and no sequela was found.[Conclusion]The early complications of Vertex technique in treating dens axis fracture with atlantoaxial joint dislocation can be prevented.The timely treatment must be performed when it occurs,and the effect would be satisfactory.
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Objective To establish a three-dimensional finite element model and make mechanical analysis of "V"-type atlantoaxial reduction and internal fixation. Methods According to "V"-type atlantoaxial and internal fixation,based on screw-type Ⅱ design parameters,and using Pro/E 2001 and MSC.Patran 2005 software,we set up a finite element model and calculated the region containing the node scope of the force as the sites binding and 100N mechanics adding. Results The model looked realistic,geometric similarity.The deformation stress field mainly concentrated in the reset device V-tip arm bending and stability.The strength of its maximum stress was 4.78MPa,and the scope had 2794 nodes.V-type wing of the acute angle point of convergence of the premises to bear the stress intensity followed.It was 0.31MPa,and the scope had 1953 nodes.V-type wing by the end of edge was the smallest for the 1.22?10-3MPa,and there was the scope of 1730 nodes. Ⅱ-shaped fixed nail stress concentrated at the central parts of tooth and the art on both sides of teeth,with maximum stress intensity of 1.68?10-2MPa,and there was the scope of 1146 nodes. Conclusion The reduction and fixation devices to load at the time of recovery deformation forces and mechanical characteristics adapted to Ni-Ti shape memory alloy material functions and super-elasticity completely,which meets the clinical needs.