3D-printed vertebral body in anterior spinal reconstruction after total spondylectomy for patients with cervical chordoma / 北京大学学报(医学版)

OBJECTIVE@#To investigate whether 3D-printed artificial vertebral body can reduce prosthesis subsidence rate for patients with cervical chordomas, through comparing the rates of prosthesis subsidence between 3D printing artificial vertebral body and titanium mesh for anterior spinal reconstruction after total spondylectomy.@*METHODS@#This was a retrospective analysis of patients who underwent surgical treatment for cervical chordoma at our hospital from March 2005 to September 2019. There were nine patients in the group of 3D artificial vertebral body (3D group), and 15 patients in the group of titanium mesh cage (Mesh group). The patients' characteristics and treatment data were extracted from the medical records, including age, gender, CT hounsfield unit of cervical vertebra and surgical information, such as the surgical segments, time and blood loss of surgery, frequency and degree of prosthesis subsidence after surgery. Radiographic observations of prosthesis subsidence during the follow-up, including X-rays, CT, and magnetic resonance imaging were also collected. SPSS 22.0 was used to analysis the data.@*RESULTS@#There was no significant difference between the two groups in gender, age, CT hounsfield unit, surgical segments, time of surgery, blood loss of posterior surgery and total blood loss. Blood loss of anterior surgery was 700 (300, 825) mL in 3D group and 1 500 (750, 2 800) mL in Mesh group (P < 0.05). The prosthesis subsidence during the follow-up, 3 months after surgery, there was significant difference between the two groups in mild prosthesis subsidence (P < 0.05). The vertebral height of the 3D group decreased less than 1 mm in eight cases (no prosthesis subsidence) and more than 1 mm in one case (mild prosthesis subsidence). The vertebral height of the Mesh group decreased less than 1 mm in five cases (no prosthesis subsidence), and more than 1 mm in eight cases (mild prosthesis subsidence). Two patients did not have X-rays in 3 months after surgery. There was a statistically significant difference between the two groups in the prosthesis subsidence rate at the end of 12 months (P < 0.01). The vertebral height of eight cases in the 3D group decreased less than 1 mm (no prosthesis subsidence) and one case more than 3 mm (severe prosthesis subsidence). Four of the 15 cases in the Mesh group decreased less than 1 mm (no prosthesis subsidence), two cases more than 1 mm (mild prosthesis subsidence), and nine cases more than 3 mm (severe prosthesis subsidence). There was a statistically significant difference between the two groups in the prosthesis subsidence rate at the end of 24 months (P < 0.01). The vertebral height of seven cases in the 3D group decreased less than 1 mm (no prosthesis subsidence), one case more than 3 mm (severe prosthesis subsidence), and one case died with tumor. One case in the Mesh group decreased less than 1 mm (no prosthesis subsidence), one case more than 1 mm (mild prosthesis subsidence), 11 case more than 3 mm (severe prosthesis subsidence), one case died with tumor and one lost the follow-up. Moreover, at the end of 12 months and 24 months, there was significant difference between the two groups in severe prosthesis subsidence rate (P < 0.01).@*CONCLUSION@#3D-printed artificial vertebral body for anterior spinal reconstruction after total spondylectomy for patients with cervical chordoma can provide reliable spinal stability, and reduce the incidence of prosthesis subsidence after 2-year follow-up.

Two-Year Outcomes of Midline lumbar Fusion Versus Minimally Invasive Transforaminal Lumbar Interbody Fusion in the Treatment of L4-L5 Degenerative Disease / 生物医学与环境科学（英文）

Objective@#We aimed to compare the clinical and radiological outcomes of midline lumbar fusion (MIDLF) versus minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) in patients with degenerative spondylolisthesis and/or stenosis in L4-L5 two years after surgery.@*Methods@#Consecutively treated patients with lumbar pathology who underwent MIDLF ( @*Results@#The mean operative time and hematocrit (HCT, Day 1) were significantly shorter and lower in MIDLF cases (174 min @*Conclusion@#MIDLF is comparable to MI-TLIF at L4-5 in clinical outcomes and fusion rates, and the results verified the meaningful advantage of using MIDLF for the elderly with osteoporosis.

Effect of decompression range on decompression limit of cervical laminoplasty / 中华医学杂志(英文版)

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.

Efficacy and safety of applying ultrasonic osteotome in cervical expansive open-door laminoplasty / 北京大学学报(医学版)

OBJECTIVE@#To investigate the safety and efficacy of applying ultrasonic osteotome in patients undergoning cervical expansive open-door laminoplasty (CEOL).@*METHODS@#In the study, 94 consecutive patients who were administrated in the spine group of Orthopedic Department of Peking University Third Hospital from March 2015 to March 2016 were reviewed retrospectively. All the patients were diagnosed as multilevel cervical spondylosis myelopathy and underwent CEOL. These patients were divided into two groups: ultrasonic osteotome group and traditional group, by whether the ultrasonic osteotome device was used in operation. The parameters we studied were as follows: the duration of operation, blood loss in operation, volume of drainage on the first postoperative day, days of remaining the drainage tube, preoperative and postoperative Japanese Orthopedic Association (JOA) scores, complications of cerebrospinal fluid leak and hinge bone nonunion.@*RESULTS@#Compared with the traditional group, the duration of operation of the ultrasonic osteotome group was increased, but the blood loss in operation, volume of drainage on the 1st postoperative day and days of remaining the drainage tube of the ultrasonic osteotome group were all reduced. There was no obvious difference between the two groups when considering the cerebrospinal fluid leak. At the end of the 3-month follow-up, the JOA score and improvement rate of the JOA score were of no obvious difference between the two groups. But the hinge bone union of the traditional group was better than the ultrasonic osteotome group. At the end of the 12-month follow-up, all the JOA score, the improvement rate of the JOA score and the hinge bone union were not obviously different between the two groups.@*CONCLUSION@#Applying ultrasonic osteotome in patients undergoing cervical expansive open-door laminoplasty is both safe and effective. Compared with the rongeur, ultrasonic osteotome can cause the delayed union of the hinge bone, but it reduces the blood loss in operation, volume of postoperative drainage and days of remaining the drainage tube.

Treatment of subcutaneous fistula secondary to cerebrospinal fluid leakage in thoracic spinal stenosis cases / 北京大学学报(医学版)

OBJECTIVE@#To investigate the treatment strategy for subcutaneous fistula secondary to cerebrospinal fluid leakage (CSFL) in thoracic spinal stenosis (TSS) cases.@*METHODS@#In the study, 186 CSFL cases diagnosed with TSS and operated in general spine group of Department of Orthopedics, Peking University Third Hospital from January 2005 to December 2014 were retrospectively reviewed, of which eleven had subcutaneous fistula secondary to CSFL and were regularly followed up. Treatment strategy for subcutaneous fistula depended on the severity of CSFL and the recovery rate of thoracic myelopathy. Japanese Orthopedic Association (JOA) score was utilized to evaluate the neurologic status of these patients preoperatively and postoperatively. Statistical analysis was conducted between preoperative and postoperative JOA scores.@*RESULTS@#All of the 11 patients were regularly followed up for at least 24 months. Six of them had ossification of the posterior longitudinal ligament (OPLL) combined with ossification of ligamentum flavum (OLF), all of them undertook "cave-in" 360° circumferential decompression of the spinal cord with instrumentation. Five cases had OLF only, and received En bloc resection of lamina and OLF and fixation. The follow-up period ranged from 30 months to 131 months, and averaged at (85±34) months. Preoperative symptoms lasted from 3 months to 8 years, and the median was 18 months. Drainages were placed for 2-6 days, and averaged at (4.2±1.1) days. Ten cases appeared with fever during the perioperative period, the maximum body temperature was (37.3-39.7) °C. Prolonged antibiotics were applied in two cases with high fever. Ten cases were treated with conservative methods, CSFL were completely absorbed during the follow-up time, of which compressive dressing was utilized in 8 cases, and punctures combined with compressive dressing were used in 2 cases. For only 1 case, conservative therapy failed and reoperation was required because of neurological deterioration arising from CSF pseudocyst. For these 11 cases, preoperative JOA score arose from (3.8±1.6) preoperatively to (8.9±1.2) at the end of the final follow-up, the recovery rate was 70.8%. No infection of wound or central nerve system were noticed, and neither were unhealing wound.@*CONCLUSION@#Most TSS cases with subcutaneous fistula secondary to CSFL could be cured by conservative methods, and reoperation is required only if myelopathy caused by cerebrospinal fluid pseudocyst is identified.

Recurrence Factors in Giant Cell Tumors of the Spine / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Giant cell tumors (GCTs) are benign, locally aggressive tumors. We examined the rate of local recurrence of spinal GCTs and sought to identify recurrence factors in patients who underwent surgery.</p><p><b>METHODS</b>Between 1995 and 2014, 94 mobile spine GCT patients were treated at our hospital, comprising 43 male and 51 female patients with an average age of 33.4 years. Piecemeal intralesional spondylectomy and total en bloc spondylectomy (TES) were performed. Radiotherapy was suggested for recurrent or residual GCT cases. Since denosumab was not available before 2014 in our country, only interferon and/or zoledronic acid was suggested.</p><p><b>RESULTS</b>Of the 94 patients, four underwent conservative treatment and 90 underwent operations. Seventy-five patients (79.8%) were followed up for a minimum of 24 months or until death. The median follow-up duration was 75.3 months. The overall recurrence rate was 37.3%. Ten patients (13.3%) died before the last follow-up (median: 18.5 months). Two patients (2.6%) developed osteogenic sarcoma. The local recurrence rate was 80.0% (24/30) in patients who underwent intralesional curettage, 8.8% (3/34) in patients who underwent extracapsular piecemeal spondylectomy, and 0 (0/9) in patients who underwent TES. The risk factors for local recurrence were lesions located in the cervical spine (P = 0.049), intralesional curettage (P < 0.001), repeated surgeries (P = 0.014), and malignancy (P < 0.001). Malignant transformation was a significant risk factor for death (P < 0.001).</p><p><b>CONCLUSIONS</b>Cervical spinal tumors, curettage, and nonintact tumors were risk factors for local recurrence. Intralesional curettage and malignancy were the most important significant factors for local recurrence and death, respectively.</p>

Etiological analysis, preventional and therapeutical strategies for the unsatisfied cervical posterior decompression surgery / 中国骨伤

<p><b>OBJECTIVE</b>To discuss the causes of unsatisfied cervical posterior decompression surgery and describe the overhauling strategies and precaution.</p><p><b>METHODS</b>The clinical data of 14 patients required revision surgery were retrospectively analyzed, and these patients with unsatisfied effects were due to cervical posterior decompression surgery from January 2012 to December 2014. Overhauling reasons were analyzed and then different revision procedures were performed. The functions of cervical cord and ambulation were evaluated respectively by modified Japanese Orthopedic Association(mJOA) score and Nurick grade according to the course order:preoperative for the first time, pre-revision and at final follow-up. Improvement rate of nerves function were calculated before and after operation for the first time, before and after revision. Above data were statistically analyzed by SPSS16.0 software.</p><p><b>RESULTS</b>Reoperation reasons including 2 patients with the insufficiency width of laminectomy, 2 patients with the inadequate length of decompression, 2 patients with nerve root and spinal cord compression caused by fractured collapse, 4 patients with closed the door of vertebral lamina, 1 patient with less open-door angle, 2 patiens with ossification of posterior longitudinal ligament (1 case complicated with close the door), 2 patients with cervical spine kyphotic deformity aggravating (1 case complicated with close the door), 1 patient with nerve root canal stenosis caused by uncovertebral joint hyperplasia. Preoperative for the first time, pre-revision and at final follow-up, mJOA scores were 11.89±1.67, 13.11±1.09, 15.61±0.59, and Nurick grades were 4.21±0.58, 3.57±0.51, 1.71±0.47, respectively. There was significant difference between final follow-up and preoperative for the first time, pre-revision(<0.05). Improvement rate of nerve function was (22.33±9.49)% with bad before and after operation for the first time, and (64.60±9.88)% with good before and after revision, with statistical significance(<0.05).</p><p><b>CONCLUSIONS</b>Individualized revision surgery based on different causes for unsatisfied cervical posterior decompression can improve the function of spinal cord. Preoperative carefully analyzing the etiological factors, thoroughly decompression can reduce the revision rate.</p>

Cervical disc arthroplasty with ProDisc-C artificial disc: 5-year radiographic follow-up results / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cervical disc arthroplasty is an alternative surgery to standard cervical decompression and fusion for disc degeneration. Different types of cervical disc prosthesis are used in China. The aim of this study was to evaluate the radiographic outcomes of cervical arthroplasty using the ProDisc-C prosthesis.</p><p><b>METHODS</b>Radiographic evaluation, including static and dynamic flexion-extension lateral images, was performed at baseline and at final follow-up.</p><p><b>RESULTS</b>Twenty six patients who had single-level ProDisc-C arthroplasty were followed up for a mean period of 63 months (56-76 months). The range of motion at the operated level was 9.3°±3.7° at baseline and 7.3°±3.5° at final follow-up, with a significant difference (P < 0.05). Seventeen of 26 levels (65.4%) developed heterotopic ossification: three were classified as grade II, 13 were classified as grade III, and 1 as grade IV, according to McAfee's classification. Forty nine adjacent segments were evaluated by lateral X-ray and 18 (36.7%) segments developed adjacent segment degenerations.</p><p><b>CONCLUSIONS</b>ProDisc-C arthroplasty had acceptable radiographic results at 5-year follow-up. The range of motion was preserved. However, more than 60% of the patients developed heterotopic ossification.</p>

Longterm outcome after the decompressive surgery for thoracic myelopathy due to the ossification of the ligamentum flavum / 中华外科杂志

<p><b>OBJECTIVES</b>To investigate the long-term surgical outcome of thoracic myelopathy caused by the ossification of the ligamentum flavum (OLF) and evaluate the related risk factors.</p><p><b>METHODS</b>Forty-four patients who underwent decompressive laminectomy with thoracic OLF between January 1990 and December 2005 and got more than 5 years follow-up were retrospectively reviewed. Among these 44 cases, there were 29 male and 15 female whose ages at operation were 52 years averagely (27-68 years). The 2-year follow-up results and long-term outcomes were classified according to the modified Epstein's standard, and then the rates of excellent or good (REG) were calculated. The correlation between the long-term REG and the patients' ages, durations of symptoms, decompressed levels, and dural leak were analyzed.</p><p><b>RESULTS</b>The mean follow-up period of these 44 cases was 8.5 years (5-19 years). The REG at 2 years after laminectomy was 77.3% (34/44), while the long-term REG was 65.9% (29/44). There was one case who had suffered from an acute spinal cord injury got a poor post-operative outcome. The other 43 cases had chronic durations, including 22 cases whose pre-operative durations of symptoms were less than 12 months and 21 cases whose durations were equal to or more than 12 months. And the long-term REG of these two groups were 77.3% (17/22) and 57.1% (12/21) respectively (P>0.05). The REG of those cases whose decompression levels were limited in T1-T9 was 78.9% (15/19), while that of those cases whose laminectomy was relevant to thoracolumbar segment (T10-L2) was 58.3% (14/24) (P>0.05). There were 7 cases who had excellent or good short-term results and poor long-term outcomes. The reasons of these changes included coexistence of lumbar spinal stenosis in three cases and the growth of the OLF at the adjacent levels in four cases.</p><p><b>CONCLUSIONS</b>Although the short-term results of the decompressive surgery for thoracic OLF is good, the regular long-term follow-up is necessary because the symptoms may reoccur or deteriorate secondary to lumbar spinal stenosis or the growth of OLF at the adjacent levels near former decompressive levels; the duration of symptoms which is more than one year and the decompression levels that is involved to T10-L2 segments are possibly related to the poor long-term outcomes.</p>

Reoperation to the ossification of the posterior longitudinal ligament / 中华外科杂志

<p><b>OBJECTIVE</b>To discuss surgical approaches of ossification of the posterior longitudinal ligament (OPLL) of cervical spine.</p><p><b>METHODS</b>Between June 2005 to July 2010, 36 patients with OPLL of cervical spine were reoperated. There were 23 male, 13 female, age from 39 to 72 years (mean 57 years). The time of the first operation to the reoperation were 4 months to 24 years, an average of 3.9 years. Among 20 patients underwent anterior corpectomy and fusion (ACD) at first operation, 14 cases combined stenosis of cervical spinal canal, 10 cases were insufficient decompression of OPLL, 5 cases injured of cervical spinal cord during the first operation, 1 case was adjacent disc herniation. Among 14 cases underwent expensive open-door laminoplasty (ELAP) at first operation, 6 cases were insufficient decompression of OPLL, 4 cases were inadequate decompressed segment, 2 cases were cervical segmental kyphosis, 2 cases were progression of OPLL combined with disc herniation. Among 2 cases underwent combined approach at first operation, 1 case was insufficient decompression of OPLL, the other was adjacent disc herniation. Their pre- and post-operative X-ray, CT and MRI were analyzed. The complications of reoperation were recorded.</p><p><b>RESULT</b>There were 30 patients followed-up, with a period of 1.5 - 4.0 years, average 1.8 years. With 36 patients, none had deterioration, 2 patients had no recovery post-reoperation, 34 patients had 31.2% Japanese Orthopedic Association score improve rate. Among 22 cases underwent ELAP at second operation, 3 cases had postoperative segmental palsy. Among 14 cases underwent ACD at second operation, 3 cases had intraoperative dural defects.</p><p><b>CONCLUSION</b>Surgical strategy for OPLL of cervical spine should consider the type of OPLL and stenosis of cervical spinal canal.</p>

Comparison of adjacent segment degeneration five years after single level cervical fusion and cervical arthroplasty: a retrospective controlled study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cervical arthroplasty is indicated to preserve cervical motion and prevent accelerated adjacent segment degeneration. Whether accelerated adjacent segment degeneration is prevented in the long term is unclear. This trial compared adjacent segment degeneration in Bryan disc arthroplasty with that in anterior cervical decompression and fusion five years after the surgery.</p><p><b>METHODS</b>We studied patients with single level degenerative cervical disc disease. The extent of adjacent segment degeneration was estimated from lateral X-rays.</p><p><b>RESULTS</b>Twenty-six patients underwent single level Bryan disc arthroplasty and twenty-four patients underwent single level anterior cervical decompression and fusion. All patients were followed up for an average of sixty months. In the Bryan arthroplasty group, nine (17.6%) segments developed adjacent segment degeneration, which was significantly lower than that (60.4%) in the anterior cervical decompression and fusion group. Eleven segments in the Bryan arthroplasty group developed heterotopic ossification according to McAfee's classification and two segments had range of motion less than 2°. In the heterotopic ossification group, four (19.5%) segments developed adjacent segment degeneration, similar to the number in the non-heterotopic ossification group (16.7%). Adjacent segment degeneration rate was 50% in grade IV group but 11.8% in grade II to III.</p><p><b>CONCLUSIONS</b>Adjacent segment degeneration was accelerated after anterior cervical decompression and fusion. However, Bryan disc arthroplasty avoided accelerated adjacent segment degeneration by preserving motion. Patients with grade IV heterotopic ossification lost motion, and the rate of adjacent segment degeneration was higher than that in patients without heterotopic ossification.</p>

Assessing validation of dual fluoroscopic image matching method for measurement of in vivo spine kinematics / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Accurate knowledge of the spinal structural functions is critical to understand the biomechanical factors that affect spinal pathology. Many studies have investigated the human vertebral motion both in vitro and in vivo. However, determination of in vivo motion of the vertebrae under physiologic loading conditions remains a challenge in biomedical engineering because of the limitations of current technology and the complicated anatomy of the spine.</p><p><b>METHODS</b>For in vitro validation, a human lumbar specimen was imbedded with steel beads and moved to a known distance by an universal testing machine (UTM). The dual fluoroscopic system was used to capture the spine motion and reproduce the moving distance. For in vivo validation, a living subject moved the spine in various positions while bearing weight. The fluoroscopes were used to reproduce the in vivo spine positions 5 times. The standard deviations in translation and orientation of the five measurements were used to evaluate the repeatability of technique. The accuracy of vertebral outline matching with metallic marks matching technology was compared.</p><p><b>RESULTS</b>The translation positions of the human lumbar specimen could be determined with a mean accuracy less than 0.35 mm and a mean repeatability 0.36 mm for the image matching technique. The repeatability of the method in reproducing in vivo human spine six degrees of freedom (6DOF) kinematics was less than 0.43 mm in translation and less than 0.65° in rotation. The accuracy of metallic marks and vertebral outline matching did not show significant difference.</p><p><b>CONCLUSIONS</b>Combining a dual fluoroscopic and computerized tomography imaging technique was accurate and reproduceable for noninvasive measurement of spine vertebral motion. The vertebral outline matching technique could be a useful technique for matching of vertebral positions and orientations which can evaluate and improve the efficacy of the various surgical treatments.</p>

Circumspinal decompression through a single posterior incision to treat thoracolumbar disc herniation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Various surgical approaches have been successfully used in the treatment of thoracolumbar disc herniation (TLDH). Although the anterior transthoracic approach has a reputation for better visualization than the posterolateral and lateral approaches, it involves the manipulation of the thoracic and pulmonary structures. Thus, this approach is technically demanding and prone to compromising the respiratory system. An ideal approach would involve adequate visualization and be accomplished through the posterior midline approach that is familiar to spine surgeons. The objective of this retrospective preliminary clinical study was to introduce a new surgical procedure, circumspinal decompression through a single posterior incision, for the treatment of TLDH (T10/11-L1/2) and to evaluate the surgical outcome of this procedure by comparing it to the conventional anterior transthoracic approach.</p><p><b>METHODS</b>In this study, 15 patients (10 males, 5 females; mean age 51 years) with symptomatic TLDH underwent the circumspinal decompression through a single posterior incision procedure between January 2008 and December 2009. Altogether, 17 herniated discs were excised, with 2 discs at T10/11, 4 discs at T11/12, 5 discs at T12/L1 and 6 discs at L1/2. Of these patients, 13 were followed up with a mean follow-up period of 23.5 months. Clinical outcomes, including operative time, blood loss, perioperative complications, postoperative time of hospitalization, neurologic status improvement, back pain and correction of local kyphosis, were investigated by comparing these data with the results from patients who underwent the anterior transthoracic approach for TLDH during the same period. The patients' neurologic status was evaluated by a modified Japanese Orthopedic Association (JOA) scoring system of 11 points. Neurologic status improvement after the surgery was assessed by calculating the recovery rate, which was equal to the (postoperative JOA score-preoperative JOA score)/(11-preoperative JOA score)×100%. The rates of patients who improved at the final follow-up were also assessed.</p><p><b>RESULTS</b>The mean operative time was 183 minutes, the mean blood loss was 1067 ml, and the mean postoperative hospitalization time was 8.4 days. Three patients suffered perioperative complications, but none of these complications involved the respiratory system. Local kyphotic angles at the fusion levels were reduced. Of the 13 patients that were followed up, 12 improved at the final follow-up, with a mean recovery rate of 52.8%. Patients who underwent the circumspinal decompression procedure showed a higher percentage of improvement at the final follow-up, a higher degree of local kyphosis correction and a lower percentage of complications (especially respiratory complications) compared to patients who underwent the anterior transthoracic decompression procedure.</p><p><b>CONCLUSIONS</b>The circumspinal decompression through a single posterior incision procedure is an effective and safe technique that is comparable to anterior tranthoracic approach for the surgical treatment of TLDH patients. It could be an attractive choice in certain circumstances.</p>

Intraoperative ultrasonography in "cave-in" 360° circumferential decompression for thoracic spinal stenosis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The surgical outcomes of decompression for thoracic spinal stenosis (TSS) are unfavorable. The purpose of this study was to determine the efficacy of intraoperative ultrasonography during "cave-in" 360° circumferential decompression surgery in patients with TSS.</p><p><b>METHODS</b>Thirteen patients with TSS underwent "cave-in" 360° circumferential decompression surgery between May 2010 and November 2010. Intraoperative ultrasonography was used after removal of the posterior wall of thoracic spinal canal to assess the morphologic restoration of the spinal cord and the anterior surface of the spinal canal. In seven patients, ultrasonography was used again after circumferential decompression to compare the cross-sectional area of the spinal cord before and after circumferential decompression.</p><p><b>RESULTS</b>The average period of follow-up was (12 ± 2) months (range 9 - 15 months). The Japanese Orthopedic Association score was significantly higher at the final follow-up (8.5 ± 2.1, range 3 - 10) than preoperatively (5.2 ± 1.1, range 3 - 7; P < 0.01). The cross-sectional area of the spinal cord was (30.8 ± 6.6) mm2 before and (53.6 ± 19.1) mm2 after circumferential decompression (P < 0.01). For five patients with TSS caused by thoracic disc herniation, the levels of circumferential decompression performed corresponded to those expected preoperatively. In contrast, for eight patients with TSS caused by ossification of the posterior longitudinal ligament, on average 1.6 ± 0.9 fewer levels of circumferential decompression were performed than expected preoperatively.</p><p><b>CONCLUSIONS</b>"Cave-in" 360° circumferential decompression is an effective therapeutic option for TSS. Intraoperative ultrasonographic evaluation may reduce the levels of circumferential decompression and ensure sufficient decompression, and increase the efficacy of this surgical technique.</p>

Risk factors for lower limb swelling after primary total knee arthroplasty / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Total knee arthroplasty (TKA) is a successful surgical technique for patients with advanced knee osteoarthritis; however, some peri-operative complications can not be predicted or avoided completely. This study aimed to investigate the factors affecting limb swelling after primary total knee arthroplasty, to guide and improve patient rehabilitation.</p><p><b>METHODS</b>Using a hospital database, we retroactively analyzed the mean changes in limb circumferences of 286 consecutive patients who underwent primary unilateral total knee arthroplasty between October 2007 and August 2009. The lower limb circumference change was calculated and analyzed statistically. The influence of age, gender, body mass index, the presence of deep vein thrombosis, methods of anti-coagulation, operation time, hidden blood loss, and type of prosthesis on post-operative lower limb swelling was studied.</p><p><b>RESULTS</b>Swelling was most pronounced from the third to the fifth post-operative day and usually occurred in both lower limbs. Swelling was significantly more pronounced in the operated limb than in the non-operated limb. The swelling above the knee was also significantly greater than that below the knee. The change in limb circumference at 10 cm above the knee was significantly different between the patients with body mass index ≤ 25 kg/m(2) and those with body mass index > 25 kg/m(2). However, the change in limb circumference at 10 cm below the knee was not significantly different between the two groups. There was no statistically significant difference in limb swelling between different age groups (P > 0.05). Similarly, gender, methods of anti-coagulation, the presence of deep vein thrombosis, the type of prosthesis, and operation time did not significantly affect post-operative limb swelling. Multivariate linear regression showed that the factors affecting post-operative limb swelling were body mass index and hidden blood loss.</p><p><b>CONCLUSIONS</b>Lower limb swelling after total knee arthroplasty is related to early post-operative hidden blood loss. The patient's hemoglobin level should be monitored. The degree of limb swelling is correlated with the patient's body mass index and the amount of hidden blood loss. Early intramuscular deep vein thrombosis formation has little effect on limb swelling.</p>

Impact factors for hidden blood loss after primary total knee arthroplasty / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the relative factors for hidden blood loss (HBL) after primary total knee arthroplasty (TKA).</p><p><b>METHODS</b>A retrospective study of 422 consecutive patients who underwent primary TKA between October 2007 and August 2009 was carried on. There were 60 male and 362 female patients with a mean age of 65.7 years. The HBL was calculated according to Gross formula. The effect of patient gender, age, body mass index (BMI), pre-operative diagnosis, unilateral or simultaneous bilateral TKA, tourniquet time, type of prosthesis, postoperative anticoagulation method and deep vein thrombosis (DVT) on the postoperative HBL were analyzed.</p><p><b>RESULTS</b>The HBL in patients underwent unilateral TKA was significantly lower than that in those underwent simultaneous bilateral TKA [(1284 ± 207) ml vs. (2248 ± 504) ml, P = 0.000]. Unvaried analysis showed that the HBL were associated with BMI, tourniquet time, prosthesis type and postoperative anticoagulation method. Multivariate linear regression analysis showed that the impact factors of postoperative HBL include BMI, tourniquet time and prosthesis type.</p><p><b>CONCLUSIONS</b>BMI, bilateral simultaneous TKA, tourniquet time and intercondylar open prosthesis impact the HBL after primary TKA. However, the influence of gender, age, diagnosis, postoperative anticoagulation method and DVT on the HBL are not significant.</p>

Morphological features of complicated thoracolumbar fractures and fixation technology of injured vertebra / 中华外科杂志

<p><b>OBJECTIVES</b>To study the morphological feature of complicated thoracolumbar fractures and the fixation technology of injured vertebra.</p><p><b>METHODS</b>From January 2005 to December 2007, 61 patients with type B and C thoracolumbar fractures according to AO classification were treated. There were 53 males and 8 females, with a mean age of 33.2 years (range, 9 to 65 years). Based on ASIA grading system of neurologic deficit, Grade A was found in 41 cases, grade B in 5 cases, Grade C in 5 cases, Grade D in 6 cases and Grade E in 4 cases. The injured vertebra located at thoracic region in 13, thoracolumbar in 39 and lumbar in 9 cases. The patients were divided into two groups: 32 cases with pedicle screws in the injured vertebra and 29 cases without pedicle screw in the injured vertebra. The analyses on the morphological features of injured vertebra were performed, and comparisons were carried out on the outcome regarding the reduction and correction of the injured vertebra, and the difference of Denis scale in pain domain and work status domain, between the two groups.</p><p><b>RESULTS</b>All the patients were followed up for an average of 3 years (range, 1.5 to 4.5 years). There were significance statistical difference in the correction loss of Cobb angle, sagittal index, correction of dislocation index, and the Denis pain scale between the two groups (P < 0.05). A better outcome was observed in the injured vertebra fixation group than the injured vertebra non-fixation group.</p><p><b>CONCLUSIONS</b>Inserting pedicle screws in the injured vertebra is effective and useful in the correction of complicated thoracolumbar fractures. It improves biomechanical stability of the spine after the operation.</p>

Application of cervical arthroplasty with Bryan cervical disc: long-term X-ray and magnetic resonance imaging follow-up results / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cervical disc arthroplasty is a new technique for treating degenerative cervical disease. Its goal is to avoid the degeneration of adjacent levels by preserving motion at the treated level. The aims of this study were to evaluate the radiologic outcomes of Bryan cervical disc replacement and the degenerative status of adjacent segments.</p><p><b>METHODS</b>Twenty-two patients at a single center underwent discectomy and implantation of Bryan cervical disc. The mean follow-up period was 60 months (57 - 69 months). Twenty patients underwent single-level arthroplasty and two underwent arthroplasty at two levels. The levels of surgery included C3/4 (3 levels), C4/5 (2 levels), C5/6 (18 levels) and C6/7 (1 level). Radiographic evaluation included dynamic X-ray examination and magnetic resonance imaging (MRI) at baseline and at final follow-up.</p><p><b>RESULTS</b>On X-ray examination, the range of motion (ROM) at the operated level was 7.2° (2.5° - 13.0°) at baseline and 7.8° (1.0° - 15.0°) at final follow-up (P > 0.05). Heterotopic ossification around the prosthesis was observed in eight levels, and two levels showed loss of motion (ROM < 2°). MRI showed worsening by a grade at the upper level in 2/22 patients, and worsening by a grade at the lower level in 3/22, according to Miyazaki's classification. No further impingement of the ligamentum flavum into the spinal canal was observed at adjacent levels, though the disc bulge was slightly increased at both the adjacent upper and lower levels at final follow-up.</p><p><b>CONCLUSIONS</b>Arthroplasty using Bryan cervical disc prosthesis resulted in favorable radiologic outcomes in this study. Disc degeneration at adjacent levels may be postponed by this technique.</p>

The application of cervical spine arthroplasty with Bryan disc and mid-term clinical and radiological follow-up results / 中华外科杂志

<p><b>OBJECTIVE</b>To study the clinical and radiological outcome of Bryan cervical disc replacement and the degenerative status on adjacent segments.</p><p><b>METHODS</b>The data of 26 cases of single level disc replacement with minimal 2 years follow-up were reviewed. CLINICAL OUTCOME was assessed with the JOA 17 score scale and Odom's score. Radiological assessment including range of motion and heterotopic ossification of operated level were recorded. Adjacent level degeneration on X-ray and MRI scan at baseline and at follow-up were compared.</p><p><b>RESULTS</b>(1) CLINICAL OUTCOME: the average JOA score was 16 with 84% improvement ratio at final follow-up in 18 cases of cervical myelopathy. Eight cases of radiculopathy were fully recovered. According to the Odom's criteria 15 cases had an excellent outcome, 7 good, 4 fair, and no case of poor result. (2) On X-ray: The range of motion (ROM) at operated level was 6.9 degrees (2 degrees-12 degrees) at baseline and 7.8 degrees (1 degree-14 degrees) at final follow-up. The heterotopic ossification around the prosthesis was observed in 7 cases and only 1 case lost movement. The average ROM was 5.3 degree in other 6 cases. There was no obvious change of disc height at adjacent levels. (3) On MRI: There was no deterioration of disc degeneration at adjacent levels at final follow-up according to Pfirrmann's classification. There was no further ligamentum flavum impingement into spinal canal observed at adjacent levels but the disc movement slightly increased at both upper and lower adjacent level at final follow-up.</p><p><b>CONCLUSIONS</b>The motion at operated level is preserved after minimal 2 years Bryan disc replacement with satisfied clinical outcome. The deterioration of disc degeneration at adjacent levels may be postponed.</p>

Histologic study of local infiltration of spinal bone giant cell tumor and chordoma / 中华外科杂志

<p><b>OBJECTIVE</b>To study the local infiltration length of spinal bone giant cell tumor and chordoma in various para-tumorous tissues.</p><p><b>METHODS</b>Surgical specimens from 7 patients with bone giant cell tumor and 10 patients with chordoma were divided into 6 groups: cortical bone group (CBG, para-tumorous tissue is bone cortex with periosteum), cartilage group (CG, para-tumorous tissues contain intervertebral disc, cartilage endplate and facet joint cartilage), trabecular bone group (TBG), paraspinal muscle tissue group (MTG), adipose tissue group (ATG) and scar tissue group (STG). Macroscopically margin (MSM) in the fresh specimens, histological margin (HLM) in the H&E sections and molecular margin (MCM) in the immunohistochemical staining sections were measured respectively. Three types of the margins of each group and MSM-HLMs, and MSM-MCMs among all groups were compared.</p><p><b>RESULTS</b>Analysis of Variance comparing MSM, HLM and MCM within each group showed that there were significant differences in all groups (P < 0.05) except for CBG and CG. MSMs were significantly longer than HLMs and MCMs in TBG and MTG (P < 0.05), and MSMs were significantly longer than MCMs in ATG and STG (P < 0.05). MSM-HLMs and MSM-MCMs of TBG and ATG were significantly larger than those of CG and CBG. MSM-HLMs and MSM-MCMs of MTG and STG were significantly larger than those of CG; in addition, MSM-MCM of STG was significantly larger than CBG's. The maximum of tumor infiltration length in CBG, MTG, ATG and STG were 11.68 mm, 13.08 mm, 8.64 mm and 9.98 mm respectively.</p><p><b>CONCLUSIONS</b>Each vertebra can be seen as a compartment, so total spondylectomy is an optimal procedure when bone giant cell tumor and chordoma localized in the compartment. To achieve a wide resection, a 1.3 cm wide margin in para-tumorous cancellous bone, a 1.5 cm wide margin in para-tumorous muscle and 1.0 cm wide margin in adipose tissues are necessary. First-time resection should be more aggressive and avoid tumor cell contamination. The surgical extent of salvage revision should contain para-tumorous scar tissue with the margin no less than 1.0 cm.</p>