[Treatment of acute unstable proximal clavicular fracture with hook plate of sternoclavicular joint].

OBJECTIVE: To investigate clinical effect of sternoclavicular hook plate in treating acute proximal clavicle fracture. METHODS: The clinical of 12 patients with acute unstable proximal clavicle fracture from June 2016 to June 2019 were retrospectively analyzed. There were 8 males and 4 females, aged from 46 to 63 years old. Ten patients caused by car accident and 2 patients caused by high falling. All patients had multiple injuries;the time from injury to surgery ranged from 2 to 14 d. All patients were treated with domestic sternoclavicular joint hook plate. The operative time ranged from 40 to 115 min. The intraoperative bleeding volume ranged from 30 to 110 ml, follow-up time ranged from 10 to 36 months, the fracture healing time ranged from 8 to 18 weeks. At the latest follow-up, the efficacy was evaluated by using shoulder joint function score (Rockwood score). RESULTS: All 12 patients were followed up, with no obvious pain at the latest follow-up. The rockwood scores of the affected shoulder ranged from 13 to 14, and the healthy shoulder ranged from 14 to 15. CONCLUSION: The sternocleidoclavicular joint plate is fixed with preformed plate. The cantilever is designed to retain the motion of the sternoclavicular joint. It's safe and simple, avoid, the injury of important organs during operation, and has a good prognosis. It is an ideal fixation method for the treatment of proximal clavicle fracture.

[Wiltse approach combined with contralateral transforaminal lumbar interbody fusion and conventional surgery for lumbar disc herniation:a case-control study].

OBJECTIVE: To compare the clinical effecty of Wiltse approach combined with contralateral transforaminal lumbar interbody fusion (TLIF) and traditional TLIF in the treatment of lumbar disc herniation and its affect on injury of multifidus muscle. METHODS: From June 2014 to September 2017, 90 patients with lumbar disc herniation combined with lumbar spine instability were divided into two groups (Wiltse approach group and traditional group) depend on the procedure of operation. Wiltse approach group was treated with Wiltse approach screw placement in one side combined with contralateral TLIF. There were 50 patients in Wiltse approach group, including 36 males and 14 females, aged 45 to 72 yearswith an average of (60.4± 3.1) years. The traditional group was treated with traditional TLIF operation. There were 40 patients in the traditional group, including 25 males and 15 females, aged 45 to 74 years with an average of (62.1±3.4) years. The operative time, intraoperative blood loss, accuracy of screw implantation, postoperative drainage volume and drainage tube removal time were recorded in two groups. Visual analogue scale (VAS) and Oswestry Disability Index (ODI)were observed before and 12 months after operation. All patients underwent CT examination preoperative and 12 months postoperative, and the CT values of bilateral multifidus muscle were measured. RESULTS: All the patients were followed up, 40 patients in traditional group were 12 to 18 months with an average of (15.3±4.3) months; and 50 patients in Wiltse approach group were 13 to 24 months with an average of (16.5± 4.1) months. There were no statistically significant differences in operative time and intraoperative blood loss between two groups (P>0.05). The accuracy of screw implantation in Wiltse approach group was higher than traditional group (P<0.05).There was no significant difference in preoperative VAS score and ODI between two groups, and 12 months after operation, VAS score and ODI in Wiltse approach group was significantly lower than traditional group (P <0.05). The postoperative drainage and drainage tube placement time in Wiltse approach group were lower than the traditional group(P<0.05). There was no statistically significant difference in CT value of multifidus muscle before operation between two groups (P>0.05), while there was statistically significant difference after operation (P<0.05). Postoperative CT values of multifidus muscles on decompression and non-decompression side were obviously reduced in traditional group (P<0.05). The CT value of the multifidus muscle on the decompression side of the Wiltse approach group was significantly lower than that before operation(P<0.05), and there was no significant difference before and after the operation on the non-decompression side (P>0.05). CONCLUSION: Compared with traditional surgical procedures, the Wiltse approach nail placement combined with contralateral TLIF has the advantage of accurate nail placement, reducing multifidus muscle damage, and reducing the incidence of postoperative intractable low back pain.

[Case control study of unilateral and bilateral intervertebral space release in the treatment of lower lumbar spondylolisthesis].

OBJECTIVE: To analyze the clinical efficacy of unilateral and bilateral intervertebral space release in the treatment of lower lumbar spondylolisthesis. METHODS: The clinical data of 41 patients with lumbar spondylolisthesis treated by surgery from October 2012 and May 2016 were retrospcetive analyzed. The patients were divided into two groups, 18 cases were enrolled in unilateral intervertebral release group, there were 7 males and 11 females, aged from 47 to 75 years old with an average of (59.3±6.4) years; according to Meyerding classification, 9 cases of I degree, 7 cases of II degree, 2 cases of III degree. And 23 cases were bilateral release group, there were 11 males and 12 females, aged from 51 to 76 years old with an average of (58.2±5.7) years; according to Meyerding classification, 11 cases of I degree, 10 cases of II degree, 2 cases of III degree. The operation time, intraoperative blood loss, bone graft fusion rate of the patients were recorded in the patients. Pre- and post-operative back and leg pain were evaluated by visual analogue scale (VAS) between two groups. The slip rate, slip angle, posterior height of intervertebral space, height of intervertebral foramen, distance of anterior and posterior displacement of vertex of intervertebral foramen were measured on X-ray and CT. And the above radiographic data were analyzed by intra-group or inter-group. RESULTS: All the patients were followed up from 9 to 24 months with an average of 12 months. The entire 41 patient obtained bone fusion at 12 months after operation. There was no statistical significance in VAS at 12 months after operation, intraoperative blood loss and operation time between two groups(P>0.05). There were statistical significance in sliding angle, posterior height of intervertebral space, height of intervertebral foramen, distance of anterior and posterior displacement of vertex of intervertebral foramen of all patients before and after operation(P<0.05). There was no statistical significance in spondylolisthesis rate in unilateral release group between pre- and post-operative(P>0.05), but there was significant difference in bilateral release group. There was statistical significance in postoperative slip angle, posterior height of intervertebral space, distance of anterior and posterior displacement of vertex of intervertebral foramen between two groups(P=0.001, 0.045, 0.001). The height of intervertebral foramen increased and the slippage rate decreased in both groups after operation, but there was no significant difference between two groups(P=0.248). CONCLUSIONS: Unilateral and bilateral intervertebral space release for the treatment of lumbar spondylolisthesis can obviously reduce the rate of spondylolisthesis, restore foraminal height and achieve better clinical efficacy. Bilateral release group can better restore the slip angle, increase posterior height of intervertebral space, reduce the distance of anterior and posterior displacement of vertex of intervertebral foramen. Especially for grade II or above degree of slippage is more appropriate.

[Research progress on pathogenesis of temporary osteoporosis in hip].

Transient osteoporosis of the hip(TOH) is classified as a type of bone marrow edema syndrome. TOH is lack of previous study and there is still controversy about his pathogenesis. In recent years, with the development of multi-discipline, such as imaging, pathology, molecular biology, the study has found that the pathological mechanism is complex, while its mechanism is still not clear, which need further research. This paper summarizes the research progress on the pathogenesis of TOH from neurogenic, osteonecrosis, abnormal vascular function, subchondral fracture, heredity and regional acceleration and son on.

Results of a modified posterolateral approach for the isolated posterolateral tibial plateau fracture.

BACKGROUND: There are few posterolateral approaches that do not require the common peroneal nerve (CPN) dissection. With the nerve exposure, it would pose a great challenge and sometimes iatrogenic damage over the surgical course. The purpose was to present a case series of patients with posterolateral tibial plateau fractures treated by direct exposure and plate fixation through a modified posterolateral approach without exposing the common peroneal nerve (CPN). MATERIALS AND METHODS: 9 consecutive cases of isolated posterior fractures of the posterolateral tibial plateau were operated by open reduction and plate fixation through the modified posterolateral approach without exposing the CPN between June 2009 and January 2012. Articular reduction quality was assessment according to the immediate postoperative radiographs. At 24 month followup, all patients had radiographs and were asked to complete a validated outcome measure and the modified Hospital for Special Surgery (HSS) Knee Scale. RESULTS: All patients were followedup, with a mean period of 29 months (range 25-40 months). Bony union was achieved in all patients. In six cases, the reduction was graded as best and in three cases the reduction was graded as middle according to the immediate postoperative radiographs by the rank order system. The average range of motion arc was 127° (range 110°-134°) and the mean postoperative HSS was 93 (range 85-97) at 24 months followup. None of the patients sustained neurovascular complication. CONCLUSIONS: The modified posterolateral approach through a long skin incision without exposing the CPN could help to expand the surgical options for an optimal treatment of this kind of fracture, and plating of posterolateral tibial plateau fractures would result in restoration and maintenance of alignment. This approach demands precise knowledge of the anatomic structures of this region.

Conservative and Operative Treatment in Extension Teardrop Fractures of the Axis.

STUDY DESIGN: A retrospective case series describing teardrop fracture of the axis. OBJECT: The purpose of the study was to clarify the clinical features, the mechanism of injury, and the potential instability of extension teardrop fractures of the axis, so as to emphasize the importance of recognizing this injury as a separate entity. SUMMARY OF BACKGROUND DATA: Teardrop fractures of the axis are rare spinal fractures, comprising only a small percentage of all injuries of the cervical spine. The stability of this fracture pattern has been a matter of debate leading to controversy regarding treatment strategies and the need for stabilization. METHODS: We retrospectively reviewed data collected from 16 patients to document the mechanism of injury, neurological deficit, treatment and clinical outcome, and imaging findings. RESULTS: Extension teardrop fractures accounted for approximately 8.9% of the upper cervical spinal injuries and 12.7% of axis fractures at the authors' institution over the same period. Six patients (4 males and 2 females) underwent surgery (4 by an anterior approach, 2 by a posterior approach). Ten cases underwent Halo-vest immobilization for a period between 6 and 12 weeks. At final follow-up, 14 cases achieved excellent results, whereas 2 patients complained of mild residual neck pain. Maximum cranial-caudal dimensions of the fragments were between 5 and 24 mm (average, 12.9 mm), and the transverse dimensions were between 5 and 22 mm (average, 11.1 mm). Fragment displacement ranged from 1 to 9 mm (average, 3.5 mm), whereas fragment rotation ranged from 10 to 52 degrees (average, 24.4 degrees) in the sagittal plane. CONCLUSIONS: Most patients with an extension teardrop fracture of the axis can be treated conservatively. On the basis of this case series, the authors suggest that large fragment size, displacement or angulation, intervertebral disk injury, neurologic deficit, or signs of instability are reasonable indications for surgical treatment.

[Mini-open trans-spatium intermuscular versus percutaneous short-segment pedicle fixation for the treatment of thoracolumbar mono-segmental vertebral fractures].

OBJECTIVE: To compare the clinical effects and radiographic outcomes of mini-open trans-spatium intermuscular and percutaneous short-segment pedicle fixation in treating thoracolumbar mono-segmental vertebral fractures without neurological deficits. METHODS: From August 2009 and August 2012, 95 patients with thoracolumbar mono-segmental vertebral fractures without neurological deficits were treated with short-segment pedicle fixation through mini-open trans-spatium intermuscular or percutaneous approach. There were 65 males and 30 females, aged from 16 to 60 years old with an average of 42 years. The mini-open trans-spatium intermuscular approach was used in 58 cases (group A) and the percutaneous approach was used in 37 cases (group B). Total incision length, operative time, intraoperative bleeding, fluoroscopy, hospitalization cost were compared between two groups. Visual analog scale (VAS) and radiographic outcomes were compared between two groups. RESULTS: All patients were followed up from 12 to 36 months with an average of 19.6 months. No complications such as incision infection, internal fixation loosening and breakage were found. In group A, fluoroscopy time was short and hospitalization cost was lower than that of group B (P<0.05). But the total incision length in group B was smaller than that of group A (P<0.05). There was no significant differences in operative time, intraoperative bleeding, postoperative VAS and radiographic outcomes between two groups (P>0.05). Postoperative VAS and radiographic outcomes were improved than that of preoperative (P<0.05). CONCLUSION: The mini-open trans-spatium intermuscular and percutaneous short-segment pedicle fixation have similar clinical effects and radiographic outcomes in treating thoracolumbar mono-segmental vertebral fractures without neurological deficits. However, in this study, the mini-open trans-spatium intermuscular approach has a short learning curve and more advantages in hospitalization cost and intraoperative radiation exposure times, and is recommendable.

[Clinical application of anterior transpediclar screw reconstruction in treating lower cervical spine fracture and dislocation].

OBJECTIVE: To investigate the clinical effects of anterior transpediclar screw (ATPS) fixation in treating lower cervical spine fracture and dislocation. METHODS: From January 2009 to December 2011, 18 patients with lower cervical spine fracture and dislocation were treated with ATPS technique, including 12 males and 6 females, aged from 17 to 47 years old with an average of 38.2 years. Severity score of lower cervical spine injuries (SLIC) ranged from 6 to 9 points with an average of 7.5 points. According to ASIA grade of spinal cord injury, 2 cases were classified in grade A, 8 cases in grade B, 6 cases in grade C and 2 cases in grade D. X-ray and CT scan were done after surgery in order to evaluate the safety of ATPS and observe the stability and fusion of injured segment. Spinal cord function was evaluated according to ASIA grade at 3 months after operation and last follow-up. RESULTS: All patients were followed up for 6 to 15 months with an average of 9.5 months. Three months after operation, in aspect of spinal cord function, 8 cases improved 1 grade, 2 cases improved 2 grades; and at final follow-up, 7 cases improved 1 grade, 4 cases improved 2 grades. All patients obtained bony fusion 6 to 8 months after operation with an average of 6.5 months. After operation, 1 case had transient hoarseness and recovered 2 months later;2 cases felt swallowing discomfort, but the symptoms disappeared after about 3 weeks by inhalation. No internal fixation breakage and loosening as well as nerve, blood vessel and esophageal injuries were found. CONCLUSION: As for three columns injury caused by lower cervical spine fracture and dislocation, treatment with anterior transpediclar screw reconstruction can achieve the effect of decompression thoroughly and restore the cervical spine height and physiological curvature. Moreover, this kind of treatment has good stability and can create the favorable conditions for the recovery of spinal cord function.

Function-preserving reduction and fixation of unstable Jefferson fractures using a C1 posterior limited construct.

STUDY DESIGN: This is a retrospective, clinical, and radiologic study of posterior reduction and fusion of the C1 arch in the treatment of unstable Jefferson fractures. OBJECTIVE: The aim of the study was to describe a new motion-preserving surgical technique in the treatment of unstable Jefferson fracture. SUMMARY OF BACKGROUND DATA: The management of unstable Jefferson fractures remains controversial. The majority of C1 fractures can be effectively treated nonoperatively with external immobilization unless there is an injury to the transverse atlantal ligament (TAL). Conservative treatment usually involves immobilization for a long time in Halo vest, whereas surgical intervention generally involves C1-C2 fusion, eliminating the range of motion of the upper cervical spine. We propose a novel method for the treatment of unstable Jefferson fractures without restricting the range of motion. METHODS: A retrospective review of 12 patients with unstable C1 fractures between April 2008 and October 2011 was performed. They were treated by inserting bilateral posterior C1 pedicle screws or lateral mass screws interconnected by a transversal rod to achieve internal fixation. There were 8 men and 4 women, with an average age of 35.6 years (range, 20-60 y). Presenting symptoms included neck pain, stiffness, and decreased range of motion but none had neurological injury. Seven patients had bilateral posterior arch fractures associated with unilateral anterior arch fractures (posterior 3/4 Jefferson fracture, Landells type II), and 5 had unilateral anterior and posterior arch fractures (half-ring Jefferson fracture, Landells type II). Seven patients had intact TAL, and 5 patients had fractures and avulsion of the attachment of TAL (Dickman type II). RESULTS: A total of 24 screws were inserted. Five cases had screws placed in the lateral mass: 3 because of posterior arch breakage, and 2 because the height of the posterior arch at the entry point was <4 mm. The remaining 7 cases had pedicle screw fixation. One patient had venous plexus injury during exposure of lower margin of the posterior arch; however, successful hemostasis was achieved with Gelfoam. Postoperative x-ray and computed tomography scan showed partial breach of the transverse foramen caused by a screw in 1 case, and breach of the inner cortex of the pedicle caused by screw displacement in 1 case; however, no spinal cord injury or vertebral artery injury was found. The remaining screws were in good position. Patients were followed up for 6-40 months (average, 22 mo). All cases had recovery of range of motion of the cervical spine to the preinjury level by 3-6 months after surgery, with resolution of pain. At 6 months follow-up, plain radiographs and computed tomography scans revealed satisfactory cervical alignment, no implant failure, and satisfactory bony fusion of the fractures; no C1-C2 instability was observed on the flexion-extension radiographs. CONCLUSIONS: C1 posterior limited construct is a valid technique and a feasible method for treating unstable Jefferson fractures, which allows preservation of the function of the craniocervical junction, without significant morbidity.

[Analysis of epidural hematoma formative reason and its preventive measure after anterior cervical operation].

OBJECTIVE: To explore the risk factors,preventive measure of epidural hematoma after anterior cervical operation. METHODS: From June 2005 and December 2012, 1,452 patients underwent anterior cervical operation in our hospital. Epidural hematoma occurred in 5 cases after operation and the incidence rate was 0.34%. There were 4 males and 1 female with an average age of 46.4 years (ranged, 33 to 55); 3 cases with cervical myelopathy, 1 case with cervical myelopathy and C5 vertebral angeioma, 1 case with ossification of cervical posterior longitudinal ligament. The occurred time,main clinical situation,duration of symptoms,operative management of epidural hematoma were analyzed. RESULTS: Five patients with epidural hematoma occurred within 24 h; the average interval between onset of symptoms and surgery was 4 h (ranged, 2 to 7). Operative treatment was accomplished in 5 cases by exploration and hematoma evacuation. There was significant improvement in all patients after reoperation. Epidural hematoma occurred again in one patient at 5 h after hematoma evacuation, and reoperation were performed to treat it. All patients were followed up from 6 to18 months with an average of 13.8 months. No recurrence was found. CONCLUSION: Intensive care in 24 h postoperatively is important because of epidural hematoma often occurs in this period,especialy in the period of 6-8 h postoperativey. Clinical findings and MRI can early diagnose epidural hematoma and help treatment. Once it is identified and surgical evacuation would be performed on time.

Accuracy and complications associated with the freehand C-1 lateral mass screw fixation technique: a radiographic and clinical assessment.

OBJECT: The aims of this study were to evaluate a large series of posterior C-1 lateral mass screws (LMSs) to determine accuracy based on CT scanning findings and to assess the perioperative complication rate related to errant screw placement. METHODS: Accuracy of screw placement was evaluated using postoperative CT scans obtained in 196 patients with atlantoaxial instability. Radiographic analysis included measurement of preoperative and postoperative CT scans to evaluate relevant anatomy and classify accuracy of instrumentation placement. Screws were graded using the following definitions: Type I, screw threads completely within the bone (ideal); Type II, less than half the diameter of the screw violates the surrounding cortex (safe); and Type III, clear violation of transverse foramen or spinal canal (unacceptable). RESULTS: A total of 390 C-1 LMSs were placed, but 32 screws (8.2%) were excluded from accuracy measurements because of a lack of postoperative CT scans; patients in these cases were still included in the assessment of potential clinical complications based on clinical records. Of the 358 evaluable screws with postoperative CT scanning, 85.5% of screws (Type I) were rated as being in the ideal position, 11.7% of screws (Type II) were rated as occupying a safe position, and 10 screws (2.8%) were unacceptable (Type III). Overall, 97.2% of screws were rated Type I or II. Of the 10 screws that were unacceptable on postoperative CT scans, there were no known associated neurological or vertebral artery (VA) injuries. Seven unacceptable screws erred medially into the spinal canal, and 2 patients underwent revision surgery for medial screws. In 2 patients, unilateral C-1 LMSs penetrated the C-1 anterior cortex by approximately 4 mm. Neither patient with anterior C-1 penetration had evidence of internal carotid artery or hypoglossal nerve injury. Computed tomography scanning showed partial entry of C-1 LMSs into the VA foramen of C-1 in 10 cases; no occlusion, associated aneurysm, or fistula of the VA was found. Two patients complained of postoperative occipital neuralgia. This was transient in one patient and resolved by 2 months after surgery. The second patient developed persistent neuralgia, which remained 2 years after surgery, necessitating referral to the pain service. CONCLUSIONS: The technique for freehand C-1 LMS fixation appears to be safe and effective without intraoperative fluoroscopy guidance. Preoperative planning and determination of the ideal screw insertion point, the ideal trajectory, and screw length are the most important considerations. In addition, fewer malpositioned screws were inserted as the study progressed, suggesting a learning curve to the technique.

[Progress on cervical anterior transpedicular screw fixators for lower cervical vertebrae].

Compared with the traditional anterior and posterior operation,anterior transpedicular screw fixation (ATPS) has many advantages of hiomechanics, relative safety. Both problems of decompression and reconstruction can be resolved only through an anterior approach. A rather peculiar anatomic channel was used in ATPS, but no special tools was used in system supporting for anterior pedicle screw to place,so the indications of ATPS of lower cervical vertebrae is relatively narrow,it cannot replace of traditional anterior and posterior surgery. Problems of accurately inserting screws and the development of internal fixation device about ATPS is a hot spot of current research and a future direction. In recent years,many scholars have systematically studied the technique, and applied it in clinic gradually and achieved good effects. In order to improve the level of application,recent articles were analyzed retrospectively in this paper,and the studies of anatomy,biomechanical and clinical application of ATPS were reviewed.

[The anatomical feasibility analysis of posterior laminar screw fixation techniques in upper thoracic vertebrae].

OBJECTIVE: To investigate the anatomical feasibility and the technique of T(1)-T(3) crossing laminar screws fixation in the adult population. METHODS: There were 33 dry upper thoracic vertebras specimen which included respectively T(1), T(2), T(3) were studied. Spinous process height (Hs), bilateral laminar height (H), length of superior laminar screws (Ls), length of inferior laminar screws (Li), bilateral thickness of laminar (TL) and crossing angle the laminar (A) were measured. On the basis of modified Kretze's technique, T(1) crossing laminar screws implantation was performed under visual control. The crossing laminar screws position were evaluated by X-ray and visualizing. RESULTS: The mean Hs of T(1) was the highest which was (15.7 ± 1.6) mm; the mean H of T(3) was the highest which was (18.7 ± 1.1) mm; the TL and A of T(1) were (6.3 ± 0.9) mm and 101.8° ± 4.5°, that of T(2) were (6.9 ± 1.0) mm and 101.9° ± 4.3°, that of T(3) were (6.5 ± 0.9) mm and 102.9° ± 4.4°, respectively. There were no significant differences between the values of the H and TL on left and right sides (P > 0.05). The Ls of T(1), T(2), T(3) were shorter than Li of that [(31.7 ± 2.4) mm vs. (37.3 ± 2.3) mm, (25.8 ± 2.2) mm vs. (32.3 ± 2.7) mm, (25.3 ± 2.7) mm vs. (31.2 ± 2.9) mm, respectively]. There was significant statistically difference between the values of the Ls and Li on the same vertebra (P < 0.05). The mean TL of T(2) was the thickest, which was significant statistically thicker than that of T(1) (t = 8.876, P < 0.01), which was not significant statistically thicker than that of T(3) (t = 1.919, P > 0.05). The T(1) crossing laminar screws were successfully placed, without impingement of the spinal canal. CONCLUSIONS: It is feasible to place T(1), T(2), T(3) crossing laminar screws in most people. This study provides anatomic guidelines to allow for accurate screw selection and insertion.

[Radiological studies on the best entry point and trajectory of anterior cervical pedicle screw in the lower cervical spine].

OBJECTIVE: To explore the best entry point and trajectory of anterior cervical screw in the cervical screw by radiological studies, and provide reference for clincal application. METHODS: From January 2008 to December 2010,50 patients were scanned by cervical CT and confirmed no obvious defect of lower cervical spine. Of them, 27 cases were males and 23 were females, ranged the age from 38 to 83 years ( mean 58.5 years). On horizontal axis, the camber angle of C3-C7 anterior lower cervical pedicle of vertebral arch axis (alpha) and distance between (axial length, AL) of anterior cervical pedicle axial line was measured from C3 to C7. Vertebral were divided into four areas, and from measured side of pedicle of vertebral began to record, orderly 1 to 4, the area of pedicle vertebral arch intersert into vertebral were recorded. On sagittal view, the head or tail angle (beta) and length (sagittal length, SL) of anterior cervical pedicle axial line was also measured from C3 to C7. Vertebral were divided into four areas, and from measured side of pedicle of vertebral began to record, orderly 1 to 4, the area of pedicle vertebral arch arch intersert into vertebral were recorded. The above data were statistically analyzed to find the best entry point and trajectory of anterior cervical screw in the cervical screw and insert pedicle screw. RESULTS: The lateral angle of lower cervical spine was 38 degrees to 45 degrees on transverse plane, C3 to C5 increasing gradually, C5 to C7 decreasing. On sagittal view, C3,C4 pedicle were head tulting, C5 were basic level, C6,C7 were tail. C3 to C5 decreasing gradually, C5 to C7 increasing gradually. C3 to C7 in AL and SL increased gradually. On horizontal axis, the intersection of C3,C4 and C5 were in the second area, the number of C6 in the second and third area were the same, but C7 were in the third area. The intersection in the first and forth area were less. On sagittal view,the intersection of C3,C4 and C5 were in the first area,the number of C6 in third and forth area were less. Six pedicle screws of 3 cases were insert into lower cervical spine, and obtained good effects, no complications occurred. CONCLUSION: The best entry point of C3,C4 and C5 were located in the center line and slightly to opposite vertebral body side and upper 1/4 area; C7 were located the vertebral body side and upper 2/4 area; C6 were located between them. The best insertion point were extraversion 38 degrees to 45 degrees, C3 to C5 increased graduallly, C5 to C7 decreased on horizontal axis; On sagittal view, C3,C4 for head 5 degrees to 10 degrees, C5 were basic level, C6,C7 for tail 5 degrees to 10 degrees. The anterior cervical pedicle screw for lower cervial spine is a good and feasible internal fixation.

Short-term clinical observation of the Dynesys neutralization system for the treatment of degenerative disease of the lumbar vertebrae.

OBJECTIVE: To explore the safety and short-term efficacy of the posterior approach of the Dynesys dynamic neutralization system for degenerative disease of the lumbar vertebrae. METHODS: From March 2008 to March 2010, 32 cases of degenerative lumbar vertebral disease, 19 men and 13 women, (mean age 58 ± 5.2, range, 43-78 years), were treated with posterior laminectomy and Dynesys internal fixation. All patients had a history of over 3 months waist or leg pain that had not been relieved by conservative treatment. There were 10 cases of single lumbar intervertebral disc protrusion, 14 of degenerative lumbar spinal stenosis, 5 of degenerative lumbar isthmic spondylolisthesis, and 3 of recurrent lumbar disc protrusion after surgery. A visual analogue score (VAS) was used for pain assessment, and the Oswestry disability index (ODI) for functional evaluation of clinical outcomes. RESULTS: All patients were followed up for 6-23 months (mean, 16.4 ± 5.5 months). Forty-one segments in 32 patients were stabilized; 23 cases (71.9%) underwent single-segmental stabilization, and 9 (28.1%) two-segmental stabilization. VAS of leg pain, root and low back pain was significantly improved postoperatively. The ODI improved from preoperative 69% ± 12.6% to postoperative 28% ± 15.7% (P < 0.001). On the stabilized segment and adjacent segments above and below, the range of movement showed no statistical difference; no loosening of screws, cord and polyester spacer occurred. CONCLUSION: The Dynesys dynamic neutralization system combined with decompression can achieve satisfactory short-term clinical results in lumbar degenerative disease. This procedure system not only reduces back and leg pain, but also preserves the mobility of fixed segments, minimizes tissue injury and avoids taking bone for spinal fusion.

A new technique for anterior cervical pedicle screw implantation.

OBJECTIVE: To introduce and evaluate a new technique, anterior pedicle screw implantation, for anterior cervical reconstruction. METHODS: Seven patients (five men and two women) with an average age of 65 years were included in this group. After carefully preparation, anterior pedicle screws were implanted under fluoroscopy in all patients. The position of the anterior pedicle screws was evaluated three days postoperatively by X-ray and CT imaging. The mean recovery rate as assessed by the Japanese Orthopaedic Association (JOA) score was recorded at final follow-up. RESULTS: A total of fourteen anterior pedicle screws were implanted in our group. The average follow up period was 8 months. The mean JOA score was 12.5 preoperatively and 14.8 postoperatively. The mean improvement in the JOA score was 50.5% at final follow-up. The average local alignment improved from 4.0 of kyphosis preoperatively to 6.5 of lordosis at final follow-up. Early bony union was observed in four cases that were followed up for more than 3 months. There were no serious complications. No "pedicle perforation" was observed in any of the fourteen anterior pedicle screws, whereas one screw exposure occurred. CONCLUSION: Anterior cervical pedicle screw implantation is a feasible method for selected cases. It provides another choice for strong anterior cervical reconstruction.

[Proximal femoral nail for the treatment of unstable intertrochanteric femoral fractures].

OBJECTIVE: To investigate the clinical results of the proximal femoral nail antirotation (PFNA) system in the treatment of unstable intertrochanteric femoral fractures. METHODS: From September 2006 to September 2009, 90 patients (40 males and 50 females, ranged in age from 64 to 95 years with an average of 73.2 years with unstable intertrochanteric femoral fractures were surgically treated with PFNA. Fifty patients had the fractures in the right hip, and 40 patients had the fractures in the left hip. The fractures were classified according to the AO classification: 11 patients were type A2.1, 21 patients were type A2.2,25 patients were type A2.3 9 patients were type A3.1,6 patients were A3.2 and 18 patients were A3.3. The patients underwent surgery within a mean of 3.2 days(ranged,2 to 20.1 days) from injury. The mean hospital stay was 12.8 days(ranged,7 to 24 days). Closed reduction was achieved in all the patients. Harris hip score were used for the evaluation of clinical effects. RESULTS: The mean operation time was 36.8 min (ranged, 23 to 110 min) and the mean blood loss was 150 mi (ranged, 100 to 500 ml). The mean follow-up period was 12 months (ranged, 6 to 24 months). All the patients had fracture union. Sixty-nine patients got excellent reduction, 14 good and 7 bad. The mean collodiaphysial angle was 135.60 (ranged, 1260 to 1470). Postoperative complications included secondary varus in 2 patients,calcification at the tip of the greater trochanter in 5 patients, medial thigh pain in 7 patients,and screw cut-out in 1 petient. Ten patients had femoral shortness (mean 9.3 mm,ranging from 8 to 14 mm). The mean Harris hip score was (80.5 +/- 9.8). According to Harris hip scores evaluation system, 26 patients reached an excellent result, 37 good, 18 poor and 9 bad. CONCLUSION: Due to advantages of high union rate, short operation time, and early postoperative mobilization, PFNA osteosynthesis is an idea method for surgical treatment of unstable intertrochanteric femoral fractures.

[Case-control study on acute colonic pseudo-obstruction after total hip or knee arthroplasty].

OBJECTIVE: To investigate the incidence, predisposing factors and therapeutic modalities of acute colonic pseudo-obstruction (ACPO) in patients after total hip arthroplasties (THA) and total knee arthroplasties (TKA). METHODS: From January 2006 to December 2009, 12 patients with ACPO after THA and TKA operation were investigated retrospectively,who were viewed as the ACPO group. There were 10 males and 2 females with an average age of (78 +/- 12) years in the ACPO group. Other 853 patients without ACPO after THA and TKA operation were viewed as the control group treated at the same period. The incidence of ACPO was calculated. The clinical data were collected and compared between the two groups including patient age, gender, procedure, anesthetic class, clinical presentation, radiographic findings, duration from index surgery to diagnosis of ACPO, treatment, postoperative mobilization time, and length of hospital stay. RESULTS: The incidence of ACPO was 1.4%. The incidence of primary THA (1.3%) was higher than that of primary TKA (0.4%); the incidence of hip and knee revisions (5.0%) was higher than that of primary THA and TKA (1.0%); there was no difference in incidence between hip revisions (5.5%) and knee revisions (4.0%). The mean age was (78 +/- 12) years old in ACPO group and (71 +/- 13) in the control group. The male/female ratio was 5:1 in ACPO group and 2:3 in control group. There were statistical differences in mean age and gender ratio between the two groups. No association was found with respect to anesthetic class. On average, ACPO occurred at 2.5 days after index surgery. The abdominal distention occurred in all 12 cases, nausea or vomiting in 8 cases and abdominal pain in 3 cases. Radiographically cecal dilation occurred in all cases and intestinal dilation in 3 cases. All patients initially were treated conservatively with immediate cessation of oral intake,a nasogastric tube and oral mineral oil. Three patients received a rectal tube. Only 1 patient required endoscopic decompression. There were no deaths after ACPO in the series. Mean mobilization time after surgery averaged (5.0 +/- 2.2) days in ACPO group compared with (2.5 +/- 1.1) days in the control group. Mean hospital stay averaged (16.5 +/- 6.4) days in ACPO group compared with (10.5 +/- 4.5) days in the control group. There were statistical differences in mean mobilization time after surgery and mean hospital stay between two groups. CONCLUSION: ACPO mainly happened in old male patients. The majority cases response to conservative treatment and their prognoses are good. But ACPO will delay mobilization time after surgery and increase hospital stay.