Cost-Effectiveness and Clinical Outcomes of Lateral Lumbar Interbody Fusion With Tricalcium Phosphate and Iliac Bone Graft Compared With Posterior Lumbar Interbody Fusion With Local Bone Graft in Single-Level Lumbar Spinal Fusion Surgery in Thailand.

BACKGROUND: Nowadays, minimally invasive lateral lumbar interbody fusion (LLIF) is used to treat degenerative lumbar spine disease. Many studies have proven that LLIF results in less soft tissue destruction and rapid recovery compared with open posterior lumbar interbody fusion (PLIF). Our recent cost-utility study demonstrated that LLIF was not cost-effective according to the Thai willingness-to-pay threshold, primarily due to the utilization of an expensive bone substitute: bone morphogenetic protein 2. Therefore, this study was designed to use less expensive tricalcium phosphate combined with iliac bone graft (TCP + IBG) as a bone substitute and compare cost-utility analysis and clinical outcomes of PLIF in Thailand. METHODS: All clinical and radiographic outcomes of patients who underwent single-level LLIF using TCP + IBG and PLIF were retrospectively collected. Preoperative and 2-year follow-up quality of life from EuroQol-5 Dimensions-5 Levels and health care cost were reviewed. A cost-utility analysis was conducted using a Markov model with a lifetime horizon and a societal perspective. RESULTS: All enrolled patients were categorized into an LLIF group (n = 30) and a PLIF group (n = 50). All radiographic results (lumbar lordosis, foraminal height, and disc height) were improved at 2 years of follow-up in both groups (P < 0.001); however, the LLIF group had a dramatic significant improvement in all radiographic parameters compared with the PLIF group (P < 0.05). The fusion rate for LLIF (83.3%) and PLIF (84%) was similar and had no statistical significance. All health-related quality of life (Oswestry Disability Index, utility, and EuroQol Visual Analog Scale) significantly improved compared with preoperative scores (P < 0.001), but there were no significant differences between the LLIF and PLIF groups (P > 0.05). The total lifetime cost of LLIF was less than that of PLIF (15,355 vs 16,500 USD). Compared with PLIF, LLIF was cost-effective according to the Thai willingness-to-pay threshold, with a net monetary benefit of 539.76 USD. CONCLUSION: LLIF with TCP + IBG demonstrated excellent radiographic and comparable clinical health-related outcomes compared with PLIF. In economic evaluation, the total lifetime cost was lower in LLIF with TCP + IBG than in PLIF. Furthermore, LLIF with TCP + IBG was cost-effective compared with PLIF according to the context of Thailand. CLINICAL RELEVANCE: LLIF with less expensive TCP + IBG as bone graft results in better clinical and radiographic outcomes, less lifetime cost, and cost-effectiveness compared with PLIF. This suggests that LLIF with TCP + IBG could be utilized in lower- and middle-income countries for treating patients with degenerative disc disease.

Pseudarthrosis risk factors in lumbar fusion: a systematic review and meta-analysis.

This study presents a systematic literature review and meta-analysis of pseudarthrosis risk factors following lumbar fusion procedures. The odds ratio (OR) and 95% confidence interval (95% CI) were used for outcome measurements. The objective of this study was to identify the independent risk factors for pseudarthrosis after lumbar spinal fusion, which is crucial for mitigating morbidity and reoperation. Systematic searches in PubMed, Embase, and Scopus (1990-July 2021) were conducted using specific terms. The inclusion criteria included prospective and retrospective cohorts and case‒control series reporting ORs with 95% CIs from multivariate analysis. The quality assessment utilized the Newcastle-Ottawa scale. Meta-analysis, employing OR and 95% CI, assessed pseudarthrosis risk factors in lumbar fusion surgery, depicted in a forest plot. Of the 568 abstracts identified, 12 met the inclusion criteria (9 retrospective, 2006-2021). The 17 risk factors were categorized into clinical, radiographic, surgical, and bone turnover marker factors. The meta-analysis highlighted two significant clinical risk factors: age (95% CI 1.02-1.11; p = 0.005) and smoking (95% CI 1.68-5.44; p = 0.0002). The sole significant surgical risk factor was the number of fused levels (pooled OR 1.35; 95% CI 1.17-1.55; p < 0.0001). This study identified 17 risk factors for pseudarthrosis after lumbar fusion surgery, emphasizing age, smoking status, and the number of fusion levels. Prospective studies are warranted to explore additional risk factors and assess the impact of surgery and graft type.

Lipid Peroxidation, Reduced Glutathione, and Glutathione Peroxidase Levels in Intervertebral Discs of Patients with Lumbar Degenerative Disc Disease.

BACKGROUND Either a reduction in antioxidant levels or an accumulation of reactive oxygen species can heighten susceptibility to oxidative damage in disc cells. To date, no research has investigated the levels of lipid peroxidation products (thiobarbituric acid reactive substances [TBARs]), reduced glutathione (GSH), and glutathione peroxidase (GPx) in excised human lumbar disc tissues affected by degenerative disease. Therefore, this study aimed to evaluate lipid peroxidation products in excised disc tissues from patients with degenerative disc disease. MATERIAL AND METHODS Forty-two patients were enrolled. Patients were divided into lumbar disc degeneration (LDD) and nonlumbar disc degeneration (nonLDD) groups according to Pfirrmann classification. Intervertebral discs were obtained from all patients during the operation and were homogenized for analysis. TBARs levels were measured using fluorometry. GSH levels and GPx activity were quantified spectrophotometrically using a kinetic method. RESULTS TBARs levels in excised discs from LDD patients (5.18±4.14) were significantly higher than those from nonLDD patients (2.56±1.23, P=0.008). The levels of TBARs tended to increase with the severity of degeneration according to the Pfirrmann classification. However, these 2 groups showed no significant differences in reduced glutathione levels or glutathione peroxidase activity (P>0.05). Patients with LDD exhibited a worse health-related quality of life, reflected in lower utility and EQ-VAS scores and higher Oswestry disability index scores. CONCLUSIONS There was a notable increase in lipid peroxidation products in the excised intervertebral discs of patients with LDD. This finding suggests that oxidative stress may contribute to the development of disc degeneration.

Vertical Relationship Ratio (VRR): A High Reliability and Accuracy Radiographic Measurement for Basilar Invagination in Rheumatoid Arthritis.

BACKGROUND Previous radiographic measurements for diagnosis of a basilar invagination or impression (BI) in rheumatoid arthritis (RA) were used as reference values based on anatomical reference distances. Due to the obscured anatomical landmarks, our group proposed a new radiographic measurement based on anatomic ratios to identify BI. MATERIAL AND METHODS The vertical relationship ratio (VRR) was developed and evaluated. The VRR is the relationship between the distance obtained with the modified Ranawat method and the C3 vertebral body height. VRR was used to assess its ability to distinguish BI in 3 patient groups (28 RA with BI, 37 RA without BI, and 56 non-RA patients). The intra- and inter-observer reliability, the sensitivities, and specificities of all measurements were analyzed. The cutoff value of VRR measurement was calculated by using the receiver operating characteristic (ROC) curve. RESULTS The VRR measurement showed excellent intra- and inter-observer reliabilities. The VRR could significantly distinguish RA patients with BI from RA patients without BI. The mean VRR of RA patients with BI (1.82±0.20) was less than for the non-RA patients (2.26±0.19) and the RA patients without BI (2.24±0.19). The cutoff value of VRR from the ROC curve was below 2.025. Its sensitivity was 92.85%, specificity was 97.85%, positive predictive value was 92.86%, and negative predictive value was 97.84%. CONCLUSIONS VRR has excellent intra-/inter-observer reliability and can distinguished BI in RA patients. We recommend using VRR in preference to the other available methods for assessment and screening BI in rheumatoid arthritis.

An effectiveness and economic analyses of tricalcium phosphate combined with iliac bone graft versus RhBMP-2 in single-level XLIF surgery in Thailand.

STUDY DESIGN: Retrospective study. OBJECTIVES: To perform effectiveness and economic analyses using data from a retrospective study of patients who underwent XLIF surgery using tricalcium phosphate combined with iliac bone graft (TCP + IBG) or BMP-2 in Thailand. METHODS: Data were collected from retrospective review of the medical charts and the spine registry of Siriraj Hospital, Bangkok, Thailand. The patients were divided into two groups (TCP + IBG group and BMP-2 group). Demographic, perioperative data, radiographic, clinical results, and quality of life related to health were collected and analyzed at 2-year follow-up. All economic data were collected during the perioperative period and presented as total charge, bone graft, implant/instrumentation, operative service, surgical supply, transfusion, medication, anesthesia, laboratory, and physical therapy. RESULTS: Twenty-five TCP + IBG and 30 BMP-2 patients with spondylolisthesis and spinal stenosis as primary diagnosis were included. There were no significant differences in all demographic parameters (gender, age, underlying disease, diagnosis, and level of spine) between these two groups. During the perioperative period, the TCP + IBG group had more mean blood loss and more postoperative complications compared to the BMP-2 group. At 2 years of follow-up, there were no significant differences between the radiographic and clinical outcomes of the TCP + IBG and BMP-2 groups. The fusion rate for TCP + IBG and BMP-2 at 2 years of follow-up was 80% and 96.7%, respectively, and no statistically significant differences were observed. All clinical outcomes (Utility, Oswestry Disability Index, and EuroQol Visual Analog Scale) at 2-year follow-up improved significantly compared to preoperative outcomes, but there were no significant differences between the TCP + IBG and BMP-2 groups, either at preoperatively or at 2-year follow-up. The total charge of TCP + IBG was statistically significantly lower than that of BMP-2. Furthermore, the charges of TCP + IBG and BMP-2 during the perioperative period in Thailand were up to three times less than those in the United States. CONCLUSIONS: Using TCP + IBG as a standalone bone substitution for XLIF surgery with additional posterior instrumentation resulted in significantly lower direct medical charge compared to those using BMP-2 in the perioperative period. However, we could not detect a difference in the long-term radiographic and clinical outcomes of patients with TCP + IBG and BMP-2. These suggest that TCP + IBG may be a valuable alterative bone graft, especially in low- and middle-income countries.

Midterm outcome after en bloc resection of C2 chordoma with transoral mandibular split and mesh cage reconstruction: a case report.

INTRODUCTION: Chordomas are rare, locally aggressive tumors that often occur in the axial spine, especially in the sacrum. The treatment of chordomas located in the upper cervical spine is challenging. En bloc resection is the preferred surgical option for total tumor removal. CASE PRESENTATION: We report the case of a C2 chordoma in a 47-year-old Thai woman. She was treated with a two-stage, anterior-posterior, C2 total spondylectomy with titanium mesh cage reconstruction and radiotherapy. The first stage involved posterior stabilization from the occiput to C5, a total laminectomy, and removal of the posterior rings of the bilateral foramen transversarium to preserve the bilateral vertebral arteries. The second stage comprised a transoral mandibular split with en bloc resection of C2, followed by titanium mesh cage reconstruction and kick-off anterior cervical plating. At the 5 year follow-up, no tumor recurrence was identified on magnetic resonance imaging. The patient had no neurological deficits but still had minor complications from the anterior transoral mandibular split. CONCLUSIONS: Excellent midterm results were obtained using a transoral mandibular split with reconstruction and posterior spinal fusion from the occiput to the lower cervical spine coupled with adjuvant radiotherapy. We recommend this approach as the treatment of choice for chordoma in the upper cervical spine.

Comparative effectiveness of different pedicle screw density patterns in spinal deformity correction of small and flexible operative adolescent idiopathic scoliosis: inverse probability of treatment weighting analysis.

PURPOSES: An optimal pedicle screw density for spinal deformity correction in adolescent idiopathic scoliosis (AIS) remains poorly defined. We compared radiographic correction, operative time, estimated blood loss, and implant cost among different screw density patterns in operatively treated AIS patients. METHODS: A retrospective observational cohort study of AIS patients who underwent posterior spinal fusion using all-pedicle screw instrumentation was conducted from January 2012 to December 2018. All patients were categorized into three different pedicle screw density groups: the very low density (VLD), the low density (LD), and the high density (HD) group. The comparative effectiveness between each pairwise comparison was performed under the inverse probability of the treatment weighting method to minimize the possible confounders imbalance among treatment groups. The primary endpoints in this study were the degrees of correction and deformity progression at 2 years postoperatively. RESULTS: A total of 174 AIS patients were included in this study. The adjusted treatment effects demonstrated similar degrees of deformity correction after 2 years in the three treatment groups. However, the VLD and LD group slightly increased the curve progression at 2 years compared to the HD group by 3.9° (p = 0.005) and 3.2° (p = 0.044), respectively. Nevertheless, the limited screw density patterns (VLD and LD) significantly reduced the operative time, estimated blood loss, and implant cost per operated level. CONCLUSION: The limited pedicle screw pattern (VLD and LD) in relatively flexible AIS spinal deformity correction results in similar coronal and sagittal radiological outcomes while reducing operative time, estimated blood loss, and implant cost compared to the high-density pedicle screw instrumentation.

Lateral lumbar interbody fusion (LLIF) reduces total lifetime cost compared with posterior lumbar interbody fusion (PLIF) for single-level lumbar spinal fusion surgery: a cost-utility analysis in Thailand.

BACKGROUND: Lumbar interbody fusion techniques treat degenerative lumbar diseases effectively. Minimally invasive lateral lumbar interbody fusion (LLIF) decreases soft tissue disruption and accelerates recovery better than standard open posterior lumbar interbody fusion (PLIF). However, the material cost of LLIF is high, especially in Thailand. The cost-effectiveness of LLIF and PLIF in developing countries is unclear. This study compared the cost-utility and clinical outcomes of LLIF and PLIF in Thailand. METHODS: Data from patients with lumbar spondylosis who underwent single-level LLIF and PLIF between 2014 and 2020 were retrospectively reviewed. Preoperative and 1-year follow-up EuroQol-5D-5L and healthcare costs were collected. A cost-utility analysis with a lifetime time horizon was performed using a societal perspective. Outcomes are reported as the incremental cost-effectiveness ratio (ICER) and quality-adjusted life-year (QALY) gained. A Thai willingness-to-pay threshold of 5003 US dollars (USD) per QALY gained was used. RESULTS: The 136 enrolled patients had a mean age of 62.26 ± 11.66 years. Fifty-nine patients underwent LLIF, while 77 underwent PLIF. The PLIF group experienced greater estimated blood loss (458.96 vs 167.03 ml; P < 0.001), but the LLIF group had a longer operative time (222.80 vs 194.62 min; P = 0.007). One year postoperatively, the groups' Oswestry Disability Index and EuroQol-Visual Analog Scale scores were improved without statistical significance. The PLIF group had a significantly better utility score than the LLIF group (0.89 vs 0.84; P = 0.023). LLIF's total lifetime cost was less than that of PLIF (30,124 and 33,003 USD). Relative to PLIF, LLIF was not cost-effective according to the Thai willingness-to-pay threshold, with an ICER of 19,359 USD per QALY gained. CONCLUSIONS: LLIF demonstrated lower total lifetime cost from a societal perspective. Regard to our data, at the 1-year follow-up, the improvement in patient quality of life was less with LLIF than with PLIF. Additionally, economic evaluation modeling based on the context of Thailand showed that LLIF was not cost-effective compared with PLIF. A strategy that facilitates the selection of patients for LLIF is required to optimize patient benefits.

Total neurological recovery after surgical decompression and treatment with denosumab of large unresectable spinal giant cell tumour expanding to mediastinum.

There is a controversy over the medical treatment of unresectable spinal giant cell tumour (GCT) regarding dosing and duration. We studied a spinal GCT case that had expanded to the thoracic spinal canal and mediastinum and was successfully treated by surgical decompression and denosumab. A woman in her 30s presented with weakness in both the lower extremities. MRI revealed a large tumour in the posterior mediastinum expanding from the thoracic vertebrae (T3-6), which compressed the spinal cord. The patient underwent urgent spinal decompression with instrumentation and her tissue was sent for a pathology study. Histologically and immunohistochemistry confirmed the diagnosis of GCT. Since it was an unresectable tumour, this patient was treated with denosumab. Her neurological problem resolved after 6 months of treatment. After 4 years of follow-up, the patient displayed no further progression and no side effects from long-term denosumab usage.

Epidemiologic Study of Operative Treatment for Spinal Metastasis in Thailand : A Review of National Healthcare Data from 2005 to 2014.

OBJECTIVE: To study the factors relating to operative treatment for spinal metastasis in Thailand during 2005-2014 and to determine the hospital costs, mortality rate, and incidence of perioperative complication. METHODS: Inpatient reimbursement data from 2005 to 2014 was reviewed from three national healthcare organizations, including the National Health Security Office, the Social Security Office, and the Comptroller General's Department. The search criteria were secondary malignant neoplasm of bone and bone marrow patients (International Classification of Diseases 10th revision, Thai modification codes [ICD 10-TM], C79.5 and C79.8) who underwent spinal surgical treatment (ICD 9th revision, clinical modification procedure with extension codes [ICD 9-CM], 03.0, 03.4, 03.09, and 81.0) during 2005-2014. Epidemiology, comorbidity, and perioperative complication were analyzed. RESULTS: During the study period, the number of spinal metastasis patients who underwent operative treatment was significantly increased from 0.30 to 0.59 per 100000 (p<0.001). More males (56.14%) underwent surgical treatment for spinal metastasis than females. The most common age group was 45-64 (55.1%). The most common primary tumor sites were the unknown origin, lung, breast, prostate, and hepatocellular/bile duct. Interestingly, the proportion of hepatocellular/bile duct, breast, and lung cancer was significantly increased (p<0.001). The number of patients who had comorbidity or in-hospital complication significantly increased over time (p<0.01); however, the in-hospital mortality rate decreased. CONCLUSION: During the last decade, operative treatment for spinal metastasis increased in Thailand. The overall in-hospital complication rate increased; however, the in-hospital mortality rate decreased.

Clinical Effectiveness and Safety of Microdecompression in Thai Lumbar Spinal Stenosis Patients.

Background: Microdecompression (MD) is a minimally invasive spine surgery for lumbar spinal stenosis (LSS). However, there was no long-term outcome study of this procedure in Thailand. Objective: The aim of this study was to evaluate the safety, complications, and surgical outcomes in Thai patients who underwent MD for LSS. Material and Method: A single-institution database was reviewed for Thai patients with LSS who underwent MD during the 2005 to 2014 study period. We analyzed demographic data and clinical data, intraoperative and postoperative data, and immediate complications. Oswestry Low Back Disability Index (ODI) and EQ-5D-5L were used to measure outcomes. Results: Seventy patients were enrolled (43 female and 27 male), with an average age of 64.1+10.6 years. Mean operative time was 99.5+31.6 minutes per level. Average length of stay was 5.2+2.8 days. Estimated blood loss was 90.5+65.6 ml. The most common level was L4-5. The average follow-up was 47.5+33.8 months. All postoperative patient-reported outcome measures were statistically significantly improved compared to preoperative measures (p<0.05). Average preoperative and postoperative ODI score was 60.8+20.6 and 15.9+15.7, respectively. Average pre-operative and postoperative EQ-5D-5L scores were 35.2+23.4 and 92.2+10, respectively. Immediate complications were found in 7 patients, including 5 incidental dural tear, 1 epidural hematoma, and 1 superficial wound infection. Late complications were found in 5 patients, including 1 cerebrospinal fluid leakage and 4 additional fusion surgeries. Of note, 14 patients had grade I degenerative spondylolisthesis (DS) before surgery although none of these patients complained of significant back pain. However, 3 of 4 cases that underwent additional fusion had pre-operative DS. Conclusion: Microdecompression surgery was found to be effective for treating patients with degenerative spinal stenosis. This procedure should be cautiously used in patients with spondylolisthesis, even in the absence of significant back pain.

A Prospective Randomized Controlled Trial Comparing Posterolateral Lumbar Fusion With and Without Bone Marrow Concentrate Augmentation in Single-Level Lumbar Spondylolisthesis.

Background: Bone marrow (BM), which is a good source of stem cells and biological factors, has the potential to enhance bone fusion. Simple centrifugation technique is one of the procedures used to concentrate BM aspirate for increasing number of cells. However, there are limited clinical study for using BM concentrate augmentation in spinal fusion. Objective: This study was designed to examine the spinal fusion enhancement effects of bone marrow (BM) concentrate augmentation on poster lateral lumbar fusion (PLF) with autologous local bone graft in terms of both quality and quantity, as compared with a control procedure without BM concentrate augmentation. Material and Method: Twelve patients with L4-L5 spondylolisthesis scheduled for PLF after decompressive laminectomy and pedicle screw instrumentation were included in this study. This prospective randomized controlled trial was conducted at Siriraj Hospital during the 2009 to 2012 study period. Patients were randomly assigned to two groups. One group underwent PLF with local bone graft with BM concentrate augmentation (BM group) and the other group underwent PLF with local bone graft only (non-BM group). Clinical outcomes were evaluated by the Oswestry Disability Index (ODI) preoperatively and at 3 and 6 months after PLF. Bone fusion quality was evaluated by bony bridging on 3D-CT imaging. Fusion mass volumes were measured on quantitative 3D-CT scans at 1 week and 6 months, postoperatively. Results: Clinical outcome scores did not differ between groups. Six-month postoperative 3D-CT imaging showed complete PLF bridging in 58.3% and 100% of patients in the BM and non-BM groups, respectively. PLF mass volumes were decreased at 6 months by 51.1% in the BM group and by 48.5% in the non-BM group. One patient in the BM group had local inflammation at the BM aspiration site. Conclusion: Bone marrow concentrate augmentation in this small randomized controlled trial failed to demonstrate positive effects on autologous local bone graft in posterolateral lumbar fusion relative to both quality and quantity. The high percentage of incomplete bridging should also be noted and further investigated.

Incidence of symptomatic pulmonary embolism in spinal surgery.

BACKGROUND: Pulmonary embolism (PE) is a serious condition in orthopedic surgery. The incidence of PE, which is a sequelae of VTE in spinal surgery, is quite low. In the limited available published data, incidence rates of PE in spinal surgery are comparable to that of hip or knee arthroplasty surgery. The role of pharmacologic thomboprophylaxis remains controversial in spinal surgery. OBJECTIVE: The present study was designed to evaluate the incidence of symptomatic pulmonary embolism in spinal surgery at a single tertiary care institute. MATERIAL AND METHOD: A retrospective study of the medical records of patients that were diagnosed with symptomatic pulmonary embolism in spinal surgery from 2002-2012. The reviewed data were retrieved from the database of the Faculty of Medicine Siriraj Hospital, Mahidol University in Bangkok, Thailand. RESULTS: Three cases of symptomatic pulmonary embolism were found from 9,184 spinal surgery cases. The incidence rate was 0.033%. There were two patients with lumbar spine surgery and one case with thoracolumnbar surgery. All three cases had different underlying conditions, operations, and clinical course. One case of fatal pulmonary embolism was found in our study. CONCLUSION: Although there is a very low incidence of symptomatic pulmonary embolism, this is a catastrophic condition for affected patients and their families. PE can occur in spinal surgery cases at all levels of severity and complexity, even with no apparent risk factors.

Core decompression with bone marrow injection for the treatment of femoral head osteonecrosis.

BACKGROUND: Core decompression has been recommended in treatment of non-traumatic femoral head necrosis in early stage. Injection with patient's own bone marrow from the iliac crest might promote bone formation in the femoral head. OBJECTIVE: To evaluate the result of patients treated by this technique. MATERIAL AND METHOD: Retrospective review of a series cases by the medical records and radiographic pictures. RESULTS: There were 34 procedures from 32 patients. Mean follow-up time was 24.6 months in stage 2 and 27.8 months in stage 3. Radiographic progression was observed in 76% and 69% of stage 2 and 3. Twenty one percent of stage 2 hips underwent other surgeries when 46% of stage 3 did at last follow-up. Pain relief was observed in all cases after the surgery. CONCLUSION: The proposed technique yielded only fair results. Probably due to most patients had steroid related pathology.

Safety area for proximal metatarsal procedures.

BACKGROUND: Forefoot and tarsometatarsal surgery may be performed on the first and second metatarsal through the intermetatarsal space. However, no study has identified the safety area of the proximal metatarsal bone to avoid vascular injury. METHODS: One hundred and twenty-two uninjured embalmed feet of 31 female and 33 male cadavers aged 15 to 91 years (mean, 69.9 years) were studied. The dorsalis pedis artery was identified and dissected from its origin to the deep plantar artery. The distances from the artery to the dorsomedial aspect of first metatarsal bone, from the artery to the first tarsometatarsal joint, and from dorsalis pedis artery to the most plantar surface of second metatarsal bone were measured. RESULTS: The distance from the artery to the first tarsometatarsal joint averaged 23.1 mm (range, 12-31 mm) and the distance from the artery to the most plantar surface of the second metatarsal bone averaged 6.3 mm (range, 3-13 mm). CONCLUSIONS: The safety area for proximal metatarsal procedure is about a 69-mm(2) triangular area (23 mm from first tarsometatarsal joint and 6 mm from the most plantar surface of the second metatarsal bone). CLINICAL RELEVANCE: The study provides information of normal location and variation of deep plantar artery is which related to medial midfoot complex. This information may be used during proximal metatarsal procedures.

Core decompression and concentrated autologous bone marrow injection for treatment of osteonecrosis of the femoral head.

BACKGROUND: Osteonecrosis of the femoral head is a deficiency of blood supply resulting in femoral head collapse and joint destruction. This usually found in young adults as the leading cause of hip arthroplasty. Core decompression has been reported to reduce the bone marrow pressure for treatment of stage I and II of disease. Later, addition of concentrated bone marrow injection was proposed and reported good result. The purpose of the present study was to report the result of core decompression and concentrated bone marrow injection. MATERIAL AND METHOD: Twelve patients with osteonecrosis of femoral head underwent a core decompression and concentrated autologous bone marrow injection. Data of age, sex, underlying disease, risk of osteonecrosis were collected. Patients were followed at 3 months, 6 months, 1 year and then yearly. Radiographic data were recorded. RESULTS: Thirteen hips in 12 patients underwent the procedure. Two cases were excluded due to loss of follow-up. Mean age was 36.2 (12-56). One hip were in stage I, five in stage II and five in stage III. Risk factor included steroid usage in 6 hips and alcohol consumption in 3 hips. Underlying diseases were SLE (5), dermatitis (1), post-traumatic (1). Average nucleated cell from marrow was 91.58 x 10(6)/ml (+/- 55.9). CD34 was 17.25 x 10(6)/ml cells and percentage of recovery of mononuclear cell was 70.4%. Mean follow-up time was 3.6 years (range 1-7 years). All cases had good pain relief initially. At the last followup 8 hips (72%) had progression and 2 underwent surgery. No infection occurred. No adverse effect detected. CONCLUSION: This report showed low success rate of core decompression with concentrated autologous bone marrow grafting. The effect of delayed progression is not clear. However, the procedure appeared to be safe without immediate complication.

Complications in vertebroplasty.

BACKGROUND: Vertebroplasty is one of the minimally invasive surgery that benefit in pain relief from the osteoporotic or malignancy related vertebral compression fractures. However, many literatures reported both asymptomatic and serious complications. The aim of the present study was to summarize, collect data and report the complication ofvertebroplastyfrom our experience at a single institute. MATERIAL AND METHOD: Three hundred and twenty five vertebroplasty procedures from 236 patients performed in our institute were retrospectively reviewed. Data of diagnosis, age at the time of procedure were collected. All complications found were reviewed in detail. RESULTS: Commonly performed procedures were at thoracolumbar junction (51.4%). Osteoporosis was the most common cause of fracture. The present study found 88 (27%) complications with 26 (8%) symptomatic patients. Most common complication was cement leakage, which intervertebral disc was the most common site (42.9). Spinal canal leakage was found in 14 cases (20%). Four out of 14 cases had neurological complications and need further managements. Two cases had neurologic complications from needle injury.Adjacent level collapse found in 13 patients (4%) and remote segment collapse occurred in 5 patients (1.5%). Three had progressive kyphosis required later surgical treatment. One asymptomatic cement pulmonary embolism was found in the present study. CONCLUSION: The complications of vertebroplasty were mostly asymptomatic, but serious complication such as neurologic injury could occur. Vertebroplasty could be considered a quite safe treatment for osteoporotic vertebral fracture. Meticulous technique should be executed during the procedure to avoid the leakage complication.

Minimally invasive lumbar disectomy with the tubular retractor system: 4-7 years follow-up.

BACKGROUND: Herniated nucleus pulposus (HNP) is a common cause of low back pain. The conventional technique could injure to the surrounding structures. The tubular retractor system (METRx-X tube, Medtronic, Inc, Minneapolis, USA) is instrument to improve visualization and limited soft tissue damage for minimal invasive lumbar discetomy. OBJECTIVE: To evaluate the surgical outcomes, complications, reoperation rates and patient satisfaction for using tubular retractor system in lumbar disectomy in long term follow-up at least 4 years. MATERIAL AND METHOD: Forty-five patients who had been operated for lumbar microdisectomy with tubular retractor system between Jan 2004-Dec 2007. Demographic data, ODI, VAS scores of back pain and leg pain were collected at the date of admission, 1st week, 1st month, 3rd month and every 6 months until 48 months follow-up. RESULTS: Forty-two patients (26 males with average age 30.4; range 20-45 years, 16 females with average age 32.6; range 23-54 years) were included in the present study by excluding 3 loss follow-up patients. The average operating time with tubular retractor system was 90.5 (range 60-250) minutes.Average blood loss was about 45 (range 30-100) milliliters. Length of stay in the present study was about 4.6 days (2-10 days). The average size of incision was about 2.4 (range 2.0-3.5) centimeters. The average follow-up time of all cases was 4 years 7 months (4-7 years). The VAS score of back pain was significantly improved at 1st month post-operation (p < or = 0.05). The VAS score of leg pain was significantly improved at 1st week post-operation (p < or = 0.05). The ODI score was significantly improved at 1st month post-operation (p < or = 0.05). The complication rate was about 9.5% (4 patients) and the recurrent disc that need to re-operation rate was about 4.9% (2 patients). CONCLUSION: The tubular retractor system has the advantage over the conventional open technique. The result of operation with the tubular retractor was satisfied by the surgeons and the patients. However, This system is quite expensive and need technological equipment. Besides experience of the surgeons, using tubular retractor system also should be carefully considered for the most benefit to the patients, the surgeons and budgets of the institute.