Anatomic Considerations of Intervertebral Disc Perspective in Lumbar Posterolateral Approach via Kambin's Triangle: Cadaveric Study.

STUDY DESIGN: Anatomical study. PURPOSE: To evaluate the anatomy of intervertebral disc (IVD) area in the triangular working zone of the lumbar spine based on cadaveric measurements. OVERVIEW OF LITERATURE: The posterolateral percutaneous approach to the lumbar spine has been widely used as a minimally invasive spinal surgery. However, to our knowledge, the actual perspective of disc boundaries and areas through posterolateral endoscopic approach are not well defined. METHODS: Ninety-six measurements for areas and dimensions of IVD in Kambin's triangle on bilateral sides of L1-S1 in 5 fresh human cadavers were studied. RESULTS: The trapezoidal IVD area (mean±standard deviation) for true working space was 63.65±14.70 mm2 at L1-2, 70.79±21.88 mm2 at L2-3, 99.03±15.83 mm2 at L3-4, 116.22±20.93 mm2 at L4-5, and 92.18±23.63 mm2 at L5-S1. The average dimension of calculated largest ellipsoidal cannula that could be placed in IVD area was 5.83×11.02 mm at L1-2, 6.97×10.78 mm at L2-3, 9.30×10.67 mm at L3-4, 8.84×13.15 mm at L4-5, and 6.61×14.07 mm at L5-S1. CONCLUSIONS: The trapezoidal perspective of working zone of IVD in Kambin's triangle is important and limited. This should be taken into consideration when developing the tools and instruments for posterolateral endoscopic lumbar spine surgery.

Effect of early surgery in high surgical risk geriatric patients with femoral neck fracture and taking antiplatelet agents.

AIM: To investigate the effect of early surgical intervention on the high surgical risk elderly patients who sustained femoral neck fracture (FNF) and taking concomitant antiplatelet agents. METHODS: Between 2010 and 2012, a prospective study was conducted on 49 geriatric patients, who took antiplatelet agents, sustained FNF and underwent surgery within 72 h [early surgery (ES) group], and these were compared with a retrospective consecutive case series of patients with similar characteristics (45 cases) who had delayed surgery (DS group) after 72 h during an earlier 3-year period. Postoperative outcomes were followed for one year and compared. RESULTS: There were non-significant differences in perioperative blood loss, blood transfusion, intensive care unit requirement and postoperative mortality (P > 0.05 all). There were 2 patients (4%) in the DS group who died after surgery (P = 0.23). However, the ES group showed a significantly better postoperative outcome in terms of postoperative complications, length of hospital stay, and functional outcome (P < 0.05 all). CONCLUSION: Early hip surgery in geriatric hip fracture patients with ongoing antiplatelet treatment was not associated with a significant increase of perioperative blood loss and postoperative mortality. Moreover, ES resulted in a better postoperative surgical outcome. In early hip surgery protocol, the antiplatelet agents are discontinued and the patient is operated on within 72 h after admission, which is safe and effective for the medically fit patients.

The Impacts of Early Hip Surgery in High-Risk Elderly Taking Antithrombotic Agents and Afflicted with Intertrochanteric Fracture.

OBJECTIVE: To compare the outcome of early hip surgery in intertrochanteric fracture between high surgical risk patients receiving antiplatelet and anticoagulant drugs and those who did not. DESIGN: Retrospective study. MATERIAL AND METHOD: One hundred and four elderly patients with intertrochanteric fracture and having American Society of Anesthesiologist grade III-IV who underwent early hip surgery (within 72 hours after admission) with proximalfemoral nail anti-rotation (PFNA), were recruited and allocated into two group: antiplatelet and anticoagulant (AA-AC) group (n = 65), and no drug group (n = 39). Perioperative and postoperative outcomes were recorded and analyzed. RESULTS: The mean age was 81?8 years. The overall 1-year mortality was 6.7% (7 patients: 5 AA-AC group, and 2 no drug group, p = 0.7). Intra-operative blood loss in AA-AC group and No drug group were 87 ± 70 and 91 ± 65 ml, respectively (p = 0.74). There was no significant difference in blood transfusion, postoperative complications, and 1-year ambulatory status between both groups (p > 0.05 all). However, AA-AC group showed significant longer in duration of hospital stay compared with no drug group (p = 0.02). CONCLUSION: Early hip fracture surgery with PFNA in patients who received antiplatelet and anticoagulant medications is safe and does not significantly increase perioperative blood loss, blood transfusion, and postoperative mortality and morbidity.

The Association of Bone Mineral Density and G2014A Polymorphism in the Estrogen Receptor Alpha Gene in Osteoporotic Hip Fracture in Thai Population.

OBJECTIVE: This study aimed to determine the association of a recent identified G2014A single nucleotide polymorphism (SNP) genotype distribution in exon 8 of the estrogen receptor in postmenopausal Thai women. MATERIAL AND METHOD: A prospective study was conducted at Ramathibodi Hospital between July 2005 and July 2006. Postmenopausal Thai women, aged more than 55 years and had sustained osteoporotic hipfracture, were included. Exclusion criteria were renal and metabolic bone diseases. Age, body mass index (BMI), blood tests for metabolic bone disease, and G2014A SNP genotype, bone mineral density (BMD) were collected. The relationship between the degree of osteoporosis (normal, osteopenia, and osteoporosis) and SNP genotype was analyzed by Fisher's exact test. RESULTS: Sixty-five postmenopausal women with osteoporosis were included. The average age was 76.2 ± 10.9 years old, and the average BMI was 21.3 ± 3.5 kg/m2. The data expressing the genotype distribution of gene G2014A SNP were G/G 23.1%, G/A 29.2% and A/A 47.7%. There was no statistical difference between age and BMI in each genotype. Gene G2014A was associated with osteoporosis of lumbar spine, femoral neck, ward triangle, and femoral neck. CONCLUSION: It could be concluded that a G2014A SNP genotype in exon 8 of the estrogen receptor was associated with postmenopausal women who had osteoporotic hip fracture.

Morphometric evaluation of subaxial cervical spine using multi-detector computerized tomography (MD-CT) scan: the consideration for cervical pedicle screws fixation.

BACKGROUND: Cervical pedicle screw (CPS) insertion is a technically demanding procedure. The quantitative understanding of cervical pedicle morphology, especially the narrowest part of cervical pedicle or isthmus, would minimize the risk of catastrophic damage to surrounding neurovascular structures and improve surgical outcome. The aim of this study was to investigate morphology and quantify cortical thickness of the cervical isthmus by using Multi-detector Computerized Tomography (MD-CT) scan. METHODS: The cervical CT scans were performed in 74 patients (37 males and 37 females) with 1-mm slice thickness and then retro-reconstructed into sagittal and coronal planes to measure various cervical parameters as follows: outer pedicle width (OPW), inner pedicle width (IPW), outer pedicle height (OPH), inner pedicle height (IPH), pedicle cortical thickness, pedicle sagittal angle (PSA), and pedicle transverse angle (PTA). RESULTS: Total numbers of 740 pedicles were measured in this present study. The mean OPW and IPW significantly increased from C3 to C7 while the mean OPH and IPH of those showed non-significant difference between any measured levels. The medial-lateral cortical thickness was significantly smaller than the superior-inferior one. PTA in the upper cervical spine was significantly wider than the lower ones. The PSA changed from upward inclination at upper cervical spine to the downward inclination at lower cervical spine. CONCLUSIONS: This study has demonstrated that cervical vertebra has relatively small and narrow inner pedicle canal with thick outer pedicle cortex and also shows a variable in pedicle width and inconsistent transverse angle. To enhance the safety of CPS insertion, the entry point and trajectories should be determined individually by using preoperative MD-CT scan and the inner pedicle width should be a key parameter to determine the screw dimensions.

Using a reconstruction locking compression plate as external fixator in infected open clavicle fracture.

Open clavicle fracture is an uncommon injury mostly caused by severe direct trauma. It is often associated with multiple organ injuries. Generally, surgical intervention with debridement and fracture repair is always indicated in order to prevent infection, non-union, and malalignment. In situations of bony exposure and significant contamination concomitant with severe soft tissue damage, the external fixation is the treatment of choice because of the possibility it offers of providing stable fixation with minimal local tissue damage resulting in excellent union rates and better soft tissue outcome. Nevertheless, traditional external fixation encountered some potential problems as its bulkiness and sharp edges caused discomfort to the patient. In this study, we present an interesting case of a polytraumatized patient with a gunshot injury with complex open clavicle fracture that was successfully treated with external fixation using reconstruction with a locking compression plate as definitive treatment.

Non-union and avascular necrosis of delayed reduction and screw fixation in displaced femoral neck fracture in young adults.

OBJECTIVE: Management of displaced femoral neck fracture is crucial and vulnerable to develop complications. The present study was performed to evaluate the clinical outcome of delayed reduction with multiple screw fixations in young patients who had displaced femoral neck fracture. MATERIAL AND METHOD: The authors conducted a retrospective study in young patients, aged less than 50 years old, who underwent delayed fixation for traumatic displaced femoral neck fracture (Garden classification III or IV) at Phetchabun Hospital between 1997 and 2002. Either closed or open reduction was performed to achieve an acceptable alignment and fixed with 2 or 3 cancellous screws. Study factors were age, gender Garden classification, time to reduction, type of reduction, number of screw fixation and Garden alignment index. Non-union and avascular necrosis was assessed by clinical and radiographic findings. RESULTS: There were 26 eligible patients. The average duration of delayed surgery was 13 days (range 2 to 30 days). Twenty-three patients had completed followed-up at average 28.4 months (range 14-52 months). All patients revealed complete union and independently ambulated within 10-16 months postoperatively. Clinical and radiographic avascular necroses of the femoral head developed in 2 patients (8.7%) at 20 and 24 months after surgery. Three patients who had early fixation failure underwent hemiarthroplasty except one patient refused to re-operate. CONCLUSION: Within 30-day delayed reduction and screw fixation for the treatment of displaced femoral neck fracture in the young is still good alternative treatment to preserve the femoral head with low rate of avascular necrosis.

Treatment of acute tuberculous spondylitis by the spinal shortening osteotomy: a technical notes and case illustrations.

Surgical treatment for spinal tuberculosis is necessary in particular cases that a large amount of necrotic tissue is encountered and there is spinal cord compression. A spinal shortening osteotomy procedure has previously been described for the correction of the sagittal balance in a late kyphotic deformity, but there have been no reports on this as a surgical treatment in the acute stage. Thus, the aim of this report is to present the surgical techniques and clinical results of 3 patients who were treated with this procedure. Three patients with tuberculous spondylitis at the thoracic spine were surgically treated with this procedure. All the patients presented with severe progressive back pain, kyphotic deformity and neurological deficit. The patients recovered uneventfully from surgery without further neurological deterioration. Their pain was improved and the patients remained free of pain during the follow-up period. In conclusion, posterior spinal shortening osteotomy is an alternative method for the management of tuberculous spondylitis.

A genetic association study between growth differentiation factor 5 (GDF 5) polymorphism and knee osteoarthritis in Thai population.

OBJECTIVE: Osteoarthritis (OA) is a multi-factorial disease and genetic factor is one of the important etiologic risk factors. Various genetic polymorphisms have been elucidated that they might be associated with OA. Recently, several studies have shown an association between Growth Differentiation Factor 5(GDF5) polymorphism and knee OA. However, the role of genetic predisposing factor in each ethnic group cannot be replicated to all, with conflicting data in the literatures. Therefore, the aim of this study was to investigate the association between GDF5 polymorphism and knee OA in Thai population. MATERIALS AND METHODS: One hundred and ninety three patients aged 54-88 years who attended Ramathibodi Hospital were enrolled. Ninety cases with knee OA according to American College of Rheumatology criteria and one hundred and three cases in control group gave informed consent. Blood sample (5 ml) were collected for identification of GDF5 (rs143383) single nucleotide polymorphism by PCR/RFLP according to a standard protocol. This study protocol was approved by the Ethics Committee on human experimentation of Ramathibodi Hospital Faculty of Medicine, Mahidol University. Odds ratios (OR) and 95% confidence intervals were calculated for the risk of knee OA by genotype (TT, TC and CC) and allele (T/C) analyses. RESULTS: The baseline characteristics between two groups including job, smoking and activity were not different, except age and BMI. The entire cases and controls were in Hardy-Weinberg equilibrium (p > 0.05). The OA knee group (n = 90) had genotypic figure which has shown by TT 42.2% (n = 38), TC 45.6% (n = 41) and CC 12% (n = 11), whereas the control group (n = 103) revealed TT 32% (n = 33), TC 45.6% (n = 47), and CC 22.3% (n = 23), respectively. Genotypic TT increased risk of knee OA as compared to CC [OR = 2.41 (P = 0.04, 95%CI = 1.02-5.67)]. In the allele analysis, the T allele was found to be significantly associated with knee OA [OR = 1.53 (P = 0.043, 95%CI = 1.01-2.30)]. CONCLUSION: These data suggested that GDF5 polymorphism has an association with knee OA in Thai ethnic. This finding also supports the hypothesis that OA has an important genetic component in its etiology, and GDF5 protein might play important role in the pathophysiology of the disease.

Functional outcome after decompression and instrumented arthrodesis in degenerative lumbar spinal stenosis: factors influencing unsuccessful outcome change.

OBJECTIVE: To determine functional outcome after decompressive laminectomy and instrumented arthrodesis in patients with degenerative lumbar spinal stenosis and identify predictors of failed clinical outcome in these patients. MATERIAL AND METHOD: A retrospective cohort data were collected from January 1999 to February 2004. Degenerative lumbar spinal stenosis patients who had decompressive laminectomy and instrumented fusion with pedicular screw system and completed at least 2 years follow-up were enrolled in the present study. Outcomes included Oswestry Disability Index (ODI), Roland Morris score and patient satisfaction. Factors evaluated as outcome variables were age, gender onset, patient income, associated diseases, smoking, diagnosis of spondylolisthesis or scoliosis, number of levels of instrumentation and presence of S1 fusion. Univariate analysis for factors influencing failed clinical outcome used Chi-square and Fisher exact test and multivariate analysis used the logistic regression. RESULTS: One-hundred and fifty-eight patients were included in the present study. Mean follow-up was 2.64 years (range, 2-5 years). The mean age of the patients at the time of surgery was 60.3 years (range, 34-87 years) and 129 cases (81.7%) were female. According to the US FDA, the criteria of significant successful clinical outcome change is reduction of ODI at least 15%, the proportion of patients reporting significant successful clinical outcome change was 63.9%. Multivariate analysis identified age > 65 years, onset > 24 months and number of levels of instrumentation > 4 as the factors of failed clinical outcome change (p < 0.05). CONCLUSION: Decompression and instrumented arthrodesis in degenerative lumbar spinal stenosis gained satisfactory functional outcome. Older age, prolonged onset and long level of instrumentation were the factors of failed clinical outcome change.

The results of decompression and instrumented fusion with pedicular screw plate system in degenerative lumbar scoliosis patients with spinal stenosis: a prospective observational study.

OBJECTIVE: To study pain relief curve correction, and functional outcomes after decompression and instrumented arthrodesis in degenerative lumbar scoliosis patients with spinal stenosis. MATERIAL AND METHOD: Thirty-one degenerative scoliosis patients with symptom of spinal stenosis who underwent decompression and fusion with pedicular screw plate instrumentation and completed at least 2-year follow-up were included in this study Functional outcomes were obtained using Oswestry Disability Index (ODI) and Roland Morris score. The VAS pain relief walking ability and curve correction were collected as a result of the surgery. RESULTS: Average age of the patients at the time of surgery was 64.87years (range, 50-87years) and mean follow-up was 32 months (range, 24-60 months). There was significant improvement in all outcome parameters including pain scales, walking ability, ODI, and Roland Morris score (p < 0.05) Five patients had major complications with two cases requiring re-operation. CONCLUSION: Degenerative scoliosis with spinal stenosis is a complex spinal disease that requires decompression and stabilization procedures. Wide decompressive laminectomy and instrumented arthrodesis with pedicular screw plate system provided satisfied outcome included pain relief and functional restoration.

The evaluation of short fusion in idiopathic scoliosis.

BACKGROUND: Selective thoracic fusion in type II curve has been recommended by King et al. since 1983. They suggested that care must be taken to use the vertebra that is neutral and stable so that the lower level of fusion is centered over the sacrum. Since then there has been the trend to do shorter and selective fusion of the major curve. This study was conducted to find out whether short posterior pedicle instrumentation alone could provide efficient correction and maintain trunk balance comparing to the anterior instrumentation. MATERIALS AND METHODS: A prospective study was conducted during 2005-2007 on 39 consecutive cases with idiopathic scoliosis cases King 2 and 3 (Lenke 1A, 1B), 5C and miscellaneous. Only the major curve was instrumented unless both curves were equally rigid and of the same magnitude. The level of fusion was planned as the end vertebra (EVB) to EVB fusion, although minor adjustment was modified by the surgeons intraoperatively. The most common fusion levels in major thoracic curves were T6-T12, whereas the most common fusion levels in the thoraco-lumbar curves were T10-L3. Fusion was performed from the posterior only approach and the implants utilized were uniformly plate and pedicle screw system. All the patients were followed at least 2 years till skeletal maturity. The correction of the curve were assessed according to type of curve (lenke IA, IB and 5), severity of curve (less than 450, 450-890 and more than 900), age at surgery (14 or less and 15 or more) and number of the segment involved in instrumentation (fusion level less than curve, fusion level as of the curve and fusion more than the curve) RESULTS: The average long-term curve correction for the thoracic was 40.4% in Lenke 1A, 52.2% in Lenke 1B and 56.3% in Lenke 5. The factors associated with poorer outcome were younger age at surgery (<11 years or Risser 0), fusion at wrong levels (shorter than the measured end vertebra) and rigid curve identified by bending study. However, all patients had significant improved trunk balance and coronal hump at the final assessment at maturity. Two patients underwent late extension fusion because of junctional scoliosis. CONCLUSIONS: With modern instrumentations, the EVB of the major curve can be used at the end of the instrumentation in most cases of idiopathic scoliosis. In those cases with either severe trunk shift, younger than 11 years old, or extreme rigid curve, an extension of one or more levels might be safer. In particular situations, the concept of centering the lowest vertebra over the sacrum should be adopted.

Cervical neurofibromatosis with quadriparesis: Management by fibular strut graft.

This is a case report of an eight-year old boy with neurofibromatosis and a 120 degrees dystrophic kyphosis of the cervical spine. He presented with progressive quadriparesis caused by spondyloptosis of the C2/C3, and was successfully treated by skull traction and one-stage anterior fibular strut graft lying between the tubercle of the atlas through the C2 body slot and lower vertebrae. At seven years follow-up there was, loosening of lower vertebral screws which allowed growth and residual mobility of lower vertebral joints while the fusion of upper cervical spines was still solid.

Floor activities and degenerative spinal diseases.

BACKGROUND: The typical oriental life style in Thailand involves significant time spent on activities on the floor. This introduces an abnormal load against the spine and can cause the low back pain leading to the degenerative change of the lumbosacral region. OBJECTIVE: To determine whether various floor activities in the early adult life could result in late degenerative lumbar stenosis in the elderly patients. A case-controlled study was conducted. The patients having undergone spinal surgery according to the degenerative spinal stenosis were the case subjects. The control group consisted of the subjects having no significant back pain. The cases and the controls were matched by age, gender, and residence location. The data were collected from their medical records, roentgenograms and the standardized questionnaire. A variety of floor activities categorized by common behaviors in the Thai life style was recorded. RESULTS: There were 65 matches of cases and controls. Fifty-four patients were female performing floor activities for more than 28 times/week or more than 2 hours/week for longer than 10 years significantly increased the risk of degenerative spinal diseases by more than 15 times when being compared to the control. The most predictable activities related to the degenerative spinal diseases were occupational, cooking, and latrine use. CONCLUSION: Floor activities increased the risk of symptomatic degenerative spinal diseases in the Thai population. The question whether the prolonged postures of these routine activities could result in lumbar spinal stenosis needs more investigation in further studies.

A comparison between the Cotrel-Dubousset and the pedicle screw-plate instrumentations in the adolescent idiopathic scoliosis.

BACKGROUND: The Cotrel-Dubousset instrumentation (CD) is one of the standard instrumentations in the scoliosis surgery. Since the pedicle screw-plate system (PSP) was developed, it has resulted in the three-planar and three-dimensional correction with the minimal neurological complications. However, the correction effectiveness between these two methods is still open to question. OBJECTIVE: To compare the results of using the CD and the PSP in the treatment of adolescent idiopathic scoliosis. MATERIAL AND METHOD: A retrospective cohort study was conducted in all patients having an adolescent idiopathic scoliosis who underwent the surgery with either the CD or the PSP instrumentation at the Department of Orthopedics, Ramathibodi Hospital, during 1991 to 1998. The data of the Cobb angle, kyphotic angle, plumb line, rib hump difference and vertebral rotation were collected pre-operatively, post-operatively, and at the last follow-up. RESULTS: Forty-three patients having an adolescent idiopathic scoliosis were included. Eighteen patients: 16 females and 2 males were operated by the CD multiple hooks, and 25 patients: 23 females and 2 males were operated by the PSP instrumentation. The PSP system significantly reduced the Cobb angle and de-rotated the vertebrae in comparison with the CD group (p-value < or = 0.05). The percentage of the correction in King Type III, IV and T-L curve was higher than the other types. Both instrumentations could restore thoracic kyphosis without any major complications. CONCLUSION: The PSP system was more effective in the sagital correction, vertebral derotation and rib hump compared to the CD instrumentation. Although the PSD is a technically demanded operation, the PSP system is currently one of the most appropriate instrumentation for the adolescent idiopathic scoliosis treatment.

Association of estrogen receptor-alpha single-nucleotide polymorphism (codon 594 G-->A) and Thai patients affected by knee osteoarthritis.

BACKGROUND: Estrogen receptor-alpha single-nucleotide polymorphism (ER-alpha SNP) has previously shown its susceptibility to knee osteoarthritis (OA) but this association cannot be applied to ethnic groups with different genetic backgrounds. OBJECTIVE: To characterize the genetic association between ER-alpha SNP and knee OA in the Thai. MATERIAL AND METHOD: A case-control study was conducted at Ramathibodi Hospital from August 2007 to May 2008. Altogether, 104 cases affected by knee OA and 104 controls were included in this study. SNP rs2228480 (codon 594 G!A) on the ER-alpha gene was genotyped by a PCR-RFLP-based technique. Genotype frequencies were analyzed by logistic regression. RESULTS: ER-alpha SNP was normally distributed through the Hardy-Weinberg Equilibrium (HWE). The risk of knee OA was genetically associated to AG an AA genotypes compàred with homozygous wild-type GG (OR: 1.02, 95% CI: 0.60-1.80 for AG; OR: 1.27, 95% CI: 0.30-4.90 for AA). CONCLUSION: Our study showed that these genetic alterations might be associated with knee osteoarthritis in the Thai population. Further investigation on other informative SNPs on the ER-alpha gene should be performed to create a reliable haplotype that might provide a stronger link between genetic profiles and clinical picture.