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Dino Samartzis

Publications and source records attributed to Dino Samartzis.

At least 19 recordsLinked to original sources
PubMed2026

Comparative effectiveness and safety of pharmacological interventions for sleep outcomes in chronic non-cancer pain: a systematic review and network meta-analysis.

Sleep disturbances are highly prevalent among individuals with chronic non-cancer pain and are associated with worse pain severity and poorer prognosis. The comparative trade-offs between the effectiveness and safety of available pharmacotherapies for sleep outcomes in this population remain poorly defined. Ninety-eight RCTs involving 28,920 participants (mean age 53.2 years, 71.2% female) were included. Moderate-certainty evidence demonstrated that melatonin significantly improved sleep quality compared with placebo (standardized mean difference [SMD] = -0.60, 95%CI: -0.98, -0.22). Ten agents (e.g., amitriptyline, oxycodone, gabapentin, pregabalin, duloxetine) also showed statistically significant improvements in subjective sleep quality (SMD = -0.24 to -1.07), but most effects were supported by low-certainty evidence and were accompanied by an increased risk of adverse events (odds ratio [OR] = 1.90 to 37.00). Conversely, melatonin was not associated with an increased risk (OR = 0.88, 95%CI: 0.19, 3.94). Our findings indicate that melatonin shows promise as a safe, adjunctive option for improving sleep quality in this population, but larger, condition-specific trials are warranted to confirm these effects. Other pharmacological agents are limited by lower-certainty and unfavorable safety profiles. These results should be interpreted cautiously given limited direct comparisons, heterogeneous chronic pain populations, the high proportion of trials at high risk of bias, and the predominance of subjective sleep outcomes.

Humans↗
PubMed2006

Superior odontoid migration in the Klippel-Feil patient.

Klippel-Feil syndrome (KFS) is an uncommon condition noted primarily as congenital fusion of two or more cervical vertebrae. Superior odontoid migration (SOM) has been noted in various skeletal deformities and entails an upward/vertical migration of the odontoid process into the foramen magnum with depression of the cranium. Excessive SOM could potentially threaten neurologic integrity. Risk factors associated with the amount of SOM in the KFS patient are based on conjecture and have not been addressed in the literature. Therefore, this study evaluated the presence and extent of SOM and the various risk factors and clinical manifestations associated therein in patients with KFS. Twenty-seven KFS patients with no prior history of surgical intervention of the cervical spine were included for a prospective radiographic and retrospective clinical review. Radiographically, McGregor's line was utilized to evaluate the degree of SOM. Anterior and posterior atlantodens intervals (AADI/PADI), number of fused segments (C1-T1), presence of occipitalization, classification-type, and lateral and coronal cervical alignments were also evaluated. Clinically, patient demographics and presence of cervical symptoms were assessed. Radiographic and clinical evaluations were conducted by two independent blinded observers. There were 8 males and 19 females with a mean age of 13.5 years at the time of radiographic and clinical assessment. An overall mean SOM of 5.0 mm (range = -1.0 to 19.0 mm) was noted. C2-C3 (74.1%) was the most commonly fused segment. A statistically significant difference was not found between the amount of SOM to age, sex-type, classification-type, AADI, PADI, and lateral cervical alignment (P > 0.05). A statistically significant greater amount of SOM was found as the number of fused segments increased (r = 0.589; P = 0.001) and if such levels included occipitalization (r = 0.616; P = 0.001). A statistically significant greater amount of SOM was also found with an increase in coronal cervical alignment (r = 0.413; P = 0.036). Linear regression modeling further supported these findings as the strongest predictive variables contributing to an increase in SOM. A 7.20 crude relative risk (RR) ratio [95% confidence interval (CI) = 1.05-49.18; risk differences (RD) = 0.52] was noted in contributing to a SOM greater than 4.5 mm if four or more segments were fused. Adjusting for coronal cervical alignment greater than 10 degrees , five or more fused segments were found to significantly increase the RR of a SOM greater than 4.5 mm (RR = 4.54; 95% CI = 1.07-19.50; RD = 0.48). The RR of a SOM greater than 4.5 mm was more pronounced in females (RR = 1.68; 95% CI = 0.45-6.25; RD = 0.17) than in males. Eight patients (29.6%) were symptomatic, of which symptoms in two of these patients stemmed from a traumatic event. However, a statistically significant difference was not found between the presence of symptoms to the amount of SOM and other exploratory variables (P > 0.05). A mean SOM of 5.0 mm was found in our series of KFS patients. In such patients, increases in the number of congenitally fused segments and in the degree of coronal cervical alignment were strongly associated risk factors contributing to an increase in SOM. Patients with four or greater congenitally fused segments had an approximately sevenfold increase in the RR in developing SOM greater than 4.5 mm. A higher RR of SOM more than 4.5 mm may be associated with sex-type. However, 4.5 mm or greater SOM is not synonymous with symptoms in this series. Furthermore, the presence of symptoms was not statistically correlated with the amount of SOM. The treating physician should be cognizant of such potential risk factors, which could also help to indicate the need for further advanced imaging studies in such patients. This study suggests that as motion segments diminish and coronal cervical alignment is altered, the odontoid orientation is located more superiorly, which may increase the risk of neurologic sequelae.

Adolescent↗
PubMed2006

Osteochondroma of the sacrum: a case report and review of the literature.

STUDY DESIGN: A case report and review of the literature. OBJECTIVES: To describe the en bloc excision and postoperative outcome of an osteochondroma of the sacrum compressing the neural elements, as well as review the literature on solitary osteochondroma involving the sacrum. SUMMARY OF BACKGROUND DATA: Osteochondroma is the most common primary benign bone tumor. However, this tumor rarely involves the spine and even more rarely involves the sacrum. To the best of our knowledge, en bloc excision of a solitary osteochondroma of the sacrum has not been previously reported. METHODS: An 11-year-old male presented with disabling radicular pain in the right lower extremity. Radiologic studies showed a lesion occurring from the sacral lamina that was compressing the S2 nerve root. The tumor was excised en bloc through a posterior approach. The cavitary defect within the sacrum was reconstructed with crushed cancellous allograft and demineralized bone matrix putty. A literature review of solitary sacral osteochondroma was conducted of the English-based medical literature. RESULTS: Histologic studies showed the tumor to be an osteochondroma. After surgery, pain was completely relieved, and neurologic function was normal. At the last follow-up, the sacroiliac joint remained intact, and there was no evidence of local recurrence. A literature review revealed 4 previous cases addressing osteochondroma of the sacrum. CONCLUSIONS: Osteochondroma is a rare primary benign bone tumor that can occur in the sacrum. Local contamination and, therefore, the likelihood of local recurrence, are decreased when an en bloc, as opposed to an intralesional, excision is performed.

Child↗
PubMed2006

Symptomatic cervical disc herniation in a pediatric Klippel-Feil patient: the risk of neural injury associated with extensive congenitally fused vertebrae and a hypermobile segment.

STUDY DESIGN: A case report. OBJECTIVE: To report the occurrence of a herniated cervical disc following a high-impact activity in a pediatric Klippel-Feil patient who presented with spinal cord compression, myelopathy, and myelomalacia requiring posterior instrumented fusion followed by an anterior discectomy and fusion at the hypermobile nonfused segment. SUMMARY OF BACKGROUND DATA: The primary hallmark of Klippel-Feil syndrome (KFS) is the presence of at least one congenitally fused cervical segment. Studies have reported the potential risk of cervical injury from hypermobility associated with the nonfused cervical segment in KFS. The manifestation of a cervical disc herniation in the pediatric KFS patient is rare. To the authors' knowledge, the development of a symptomatic cervical herniated disc attributed to mechanical fatigue following a high-impact activity has not been addressed in the literature with respect to the pediatric KFS patient having extensive cervical fusion and a hypermobile segment. METHODS: A 16.8-year-old KFS boy with occipitalization of C1 and fusion of C2-C3 and C4-T1 presented with myelopathy, severe cord compression, and myelomalacia stemming from a left-sided herniated cervical disc at C3-C4 with onset following an 8-foot high rooftop jump. On radiographic evaluation, the patient's C3-C4 segment was hypermobile. RESULTS: The patient was operatively managed via a same-day combined posterior-anterior procedure. The posterior aspect of the procedure entailed a posterior lateral mass plate-screw fixation at C3-C4 with autologous iliac crest bone fusion. Anteriorly, a discectomy was performed at C3-C4 with application of an interbody tricortical autograft. After surgery, the patient wore a halo vest for 3 months, followed by a soft collar for an additional 3 months. On final follow-up at 39 months, the patient was asymptomatic with no instrumentation-related complications, fusion of the posterior graft-bed and anterior interbody graft was noted, and cervical alignment was maintained. CONCLUSIONS: A hypermobile segment in the pediatric KFS patient is a risk factor that may lead to cord compression. A symptomatic herniated cervical disc may develop from an excessive mechanical load stress in a pediatric KFS patient with multiple fused segments. In such a patient, a same-day combined posterior-anterior procedure provides cord decompression and stabilizes the spine with a favorable outcome.

Adolescent↗
PubMed2006

Radiographic assessment of segmental motion at the atlantoaxial junction in the Klippel-Feil patient.

STUDY DESIGN: A retrospective review of 33 consecutive Klippel-Feil syndrome (KFS) patients at a single institution. OBJECTIVES: To assess in KFS patients the presence and degree of radiographic segmental motion at the atlantoaxial junction, factors contributing to such motion, and associated clinical manifestations. SUMMARY OF BACKGROUND DATA: Studies suggest that abnormal segmentation in KFS patients may result in cervical hypermobility, increasing the risk of developing neurologic compromise and the need for surgical intervention. The use of the anterior and posterior atlantodens interval (AADI/PADI) has gained interest as a method for assessing atlantoaxial instability and for space available for the cord. Although helpful for identifying instability after trauma, these measurements are not understood in KFS patients. In addition, the effects of the fusion process associated with KFS on atlantoaxial motion and associated clinical findings have not been properly addressed. METHODS: Radiographs were analyzed for the presence of occipitalization, number/location of congenitally fused segments, and the AADI and PADI. RESULTS: There were 15 males and 18 females (mean age, 13.9 years). Occipitalization occurred in 48.5% of patients. A fused C2-C3 segment was noted in 72.7% of cases. More motion with respect to AADI was evident on O-C1 and C2-C3 fusion only patients, which were all asymptomatic. Overall, 24.2% of patients were symptomatic. Mean AADI and PADI difference was 2.0 mm (symptomatic: mean, 1.5 mm; asymptomatic: mean, 2.1 mm) and -1.7 mm (symptomatic: mean, -1.0 mm; asymptomatic: mean, -2.0 mm), respectively (P > 0.05). CONCLUSIONS: Hypermobility of the atlantoaxial junction, as indicated by increased AADI on flexion-extension radiographs, is not necessarily associated with an increased risk for the development of symptoms or neurologic signs in the KFS patient. Occipitalization plays an integral role in the degree of motion at the atlantoaxial region. Greatest AADI values were in patients with occipitalization and a fused C2-C3 segment. The presence of symptoms was not related to the degree of AADI change. Evaluation of the PADI provides additional information for identifying patients at risk for developing symptoms. Nonetheless, KFS patients remain largely asymptomatic.

Adolescent↗
PubMed2006

Anterior cervical discectomy and corpectomy.

OBJECTIVE: The objective of this review article is to describe the authors' operative technique for performing anterior cervical corpectomy and fusion. METHODS: The authors reviewed their operative technique and experience to clearly detail the general methods utilized to safely and effectively perform anterior cervical corpectomy and fusion. Specific nuances peculiar to the authors' technique were identified and highlighted. RESULTS: The operative technique for anterior cervical corpectomy, including nuances for enhancing ease or outcome of surgery, is described in detail. Drawings and photographs are included where appropriate to highlight specific aspects of the procedural technique. CONCLUSION: Anterior cervical corpectomy and fusion is a well known technique that proceeds in a consistent and logical sequence of maneuvers. Specific technical nuances at various points enhance the ease and safety of the technique, as well as the completeness of the eventual result.

Cervical Vertebrae↗
PubMed2006

Nonsurgical management of acute and chronic low back pain.

A variety of nonsurgical treatment alternatives exists for acute and chronic low back pain. Patients should receive appropriate education about the favorable natural history of low back pain, basic body mechanics, and methods (eg, exercises, activity modification, behavioral modification) that can reduce symptoms. Nonprescription medication is efficacious for mild to moderate pain. Nonsteroidal anti-inflammatory drugs, alone or in combination with muscle relaxants, relieve pain and improve overall symptoms of acute low back pain. Exercise therapy has limited value for acute low back pain, but strong evidence supports exercise therapy in the management of chronic low back pain. Moderately strong evidence supports the use of manipulation in acute back pain. Evidence is weak for the use of epidural corticosteroid injections in patients with acute low back pain, strong for short-term relief of chronic low back pain, and limited for long-term relief of chronic low back pain. The use of facet injections in the management of acute low back pain is not supported by evidence, nor is the effectiveness of orthoses, traction, magnets, or acupuncture. Trigger point injections are not indicated for nonspecific acute or chronic low back pain, and sacroiliac joint injections are not indicated in the routine management of low back pain. Conflicting evidence exists regarding the use of transcutaneous electrical nerve stimulation.

Acute Disease↗
PubMed2005

Traumatic fracture-dislocation of C5 on C6 through a previously solid multilevel anterior cervical discectomy and fusion: a case report and review of the literature.

BACKGROUND CONTEXT: Due to the underlying pathology and altered biomechanics, traumatic cervical fractures have been reported in patients with ankylosing spondylitis (AS), diffuse idiopathic skeletal hyperostosis (DISH), ossification of the posterior longitudinal ligament (OPLL), and combination of DISH and OPLL. However, incidence of a fracture-dislocation through a solid multilevel anterior cervical discectomy and fusion (ACDF) construct with no associated underlying pathology of AS, DISH, or OPLL but severe osteopenia has not, to the best knowledge of the authors, been reported in the medical literature. PURPOSE: To report the development of an unstable cervical spine fracture that occurred through a previous multilevel anterior cervical fusion and the challenges associated with the diagnosis and surgical management of these uncommon lesions. STUDY DESIGN/SETTING: A case report and review of the literature. METHODS: A case report entailing the clinical history, operative management, and postoperative course of a 72-year-old male patient with no known AS, DISH, or OPLL who suffered a cervical spine fracture-dislocation, secondary to a motor vehicle accident, through a previous solid three-level ACDF that was performed 20 years earlier. RESULTS: The patient underwent emergent reduction and realignment of the cervical fracture-dislocation, eventual posterior spinal fusion and stabilization with rigid segmental internal fixation, and application of external halo immobilization. At recent follow-up, he has radiographic evidence of fusion and maintenance of sagittal alignment without loss of reduction. CONCLUSIONS: Multilevel cervical fusion constructs are susceptible to traumatic injuries. Many of the same challenges in the management of the previously fused ACDF patient, who sustains a fracture-dislocation, are similar to those found in the patient with mass-inflammatory conditions or metabolic disorders, such as AS, DISH, or OPLL. In many cases, this includes severe osteopenia, long unstable fusion segments, and difficulties associated with prolonged halo vest immobilization. As a result, preoperative surgical planning should take into consideration the difficulties in achieving fracture reduction, decompression, and proper stabilization.

Accidents, Traffic↗
PubMed2005

Multiple and simultaneous spine fractures in ankylosing spondylitis: case report.

STUDY DESIGN: A case report. OBJECTIVE: To report the unique occurrence and treatment of multiple and simultaneous spine fractures in a patient with progressed ankylosing spondylitis and preexisting multilevel spine instrumentation. SUMMARY OF BACKGROUND DATA: Ankylosing spondylitis is a complex inflammatory arthritic condition that renders the spine more susceptible to fracture than individuals who do not have ankylosing spondylitis. To our knowledge, in the patient with ankylosing spondylitis, the occurrence of nonregion-specific multiple and simultaneous spine fractures, and the role of internal instrumentation in subsequent fracture development have not been addressed in the literature. METHODS: An 81-year-old white male with ankylosing spondylitis had 2 low-energy falls, resulting in 3 spine fractures. During the first fall, he had a displaced fracture at the T11-T12 level without a spinal cord injury. Fracture treatment entailed posterior instrumentation with fusion at T8-L2 and immobilization after surgery with a thoracolumbosacral orthosis brace, which led to successful healing of the injury. Approximately 2 years later, the patient had a second fall, and presented with simultaneous displaced fractures at the C6-C7 and L2-L3 levels, and an American Spinal Injury Association-A spinal cord injury. The cervical and lumbar fractures were both treated operatively via a 2-staged approach with posterior segmental instrumentation and fusion at C3-T3 and at L2-L5, respectively. A soft cervical collar and a thoracolumbosacral orthosis brace were worn after surgery. There were no intraoperative complications. RESULTS: Although anatomic reduction and stable fixation of the spinal injuries were achieved, the patient's neurologic status following the second injury remained unchanged. His postoperative course was complicated by pulmonary failure that ultimately resulted in death by the 3-month postoperative time. CONCLUSIONS: Patients with ankylosing spondylitis have a strong susceptibility to spine fracture from minor trauma, which can have devastating outcomes. Nonregion-specific multiple and simultaneous spine fractures can occur, and require thorough radiographic evaluation with imaging of the entire spinal axis, appropriate operative planning, and meticulous perioperative treatment. Preexisting internal spine instrumentation may predispose the ankylosing spondylitis spine to multiple fractures, even following a minor traumatic event. As such, the clinician should be cognizant of the possible existence of multiple and simultaneous fractures in patients with ankylosing spondylitis with preexisting internal spine instrumentation.

Aged, 80 and over↗
PubMed2005

A prospective, randomized, double-blind study evaluating the efficacy of postoperative continuous local anesthetic infusion at the iliac crest bone graft site after spinal arthrodesis.

STUDY DESIGN: Parallel design, prospective, double-blind, randomized, controlled trial composed of two independent groups treated with a continuous infusion catheter (saline vs. Marcaine) placed into the iliac crest bone graft (ICBG) site. OBJECTIVE: To determine the effects of postoperative continuous local anesthetic agent infusion at the ICBG harvest site in reducing pain, narcotic demand and usage, and improving early postoperative function after spinal fusion. SUMMARY OF BACKGROUND DATA: Harvesting iliac crest bone has been shown to be a source of pain and morbidity. Long-term patient complaints may be more closely associated with the procurement of the iliac crest graft rather than the primary surgical site. METHODS: Thirty-seven patients were enrolled in a prospective, randomized, double-blind parallel-designed study after informed consent and IRB approval was obtained. Twenty-eight patients had ICBG harvested for lumbar arthrodesis and nine for cervical arthrodesis. During spinal arthrodesis surgery, patients were randomly assigned to receive 96 mL (2 mL/hr x 48 hours) of either normal saline (control group, n = 22) or 0.5% Marcaine (treatment group, n = 15) delivered via a continuous infusion catheter placed at the ICBG harvest site. All patients received Dilaudid PCA after surgery. Pain scores, narcotic use/frequency, activity level, and length of stay (LOS) were recorded. Physicians, patients, nursing staff, and statisticians were blinded to the treatment. RESULTS: Mean patient age was 60 years and similar between groups. Narcotic dosage, demand frequency, and mean VAS pain score were significantly less in the treatment (Marcaine) group at 24 and 48 hours (P < 0.05). The average LOS was 4.1 days with no difference between Marcaine or control groups. No complications were attributed to the infusion-catheter system. CONCLUSIONS: Continuous infusion of 0.5% Marcaine at the ICBG harvest site reduced postoperative parenteral narcotic usage by 50% and decreased overall pain scores. No complications were attributed to the infusion-catheter system. The use of continuous local anesthetic infusion at the iliac crest may help in alleviating acute graft-related pain, hastening patient recovery and improving short-term satisfaction.

Adult↗
PubMed2005

Is autograft the gold standard in achieving radiographic fusion in one-level anterior cervical discectomy and fusion with rigid anterior plate fixation?

STUDY DESIGN: A review of 66 consecutive patients at a single institution who underwent one-level anterior cervical discectomy and fusion (ACDF) with rigid anterior plate fixation with allograft or autograft. OBJECTIVES: To address the efficacy of allograft to autograft with primary respect to fusion rate and secondary attention to risk factors and clinical outcome in patients undergoing one-level ACDF with rigid anterior plate fixation. SUMMARY OF BACKGROUND DATA: Although autograft is considered the gold standard in achieving optimal fusion, when compared with allograft in noninstrumented one-level ACDF and in plated and nonplated multilevel ACDF, the efficacy of allograft to autograft in one-level ACDF with rigid anterior plate fixation is not thoroughly understood. METHODS: Sixty-six consecutive patients (mean age, 45 years) at a single institution who underwent one-level ACDF with rigid anterior plate fixation with allograft (n = 35) or autograft (n = 31) were reviewed for radiographic fusion (mean, 12 months), risk factors, and clinical outcome (mean, 17 months). Smokers entailed 33.3% of the patients, and 45.5% of all patients presented with a work-related injury. An independent blinded observer reviewed at last follow-up lateral neutral and flexion/extension plain radiographs for radiographic fusion and instrumentation integrity. Clinical outcome was assessed on last follow-up and rated according to the Odom criteria. The threshold for statistical significance was established at P < 0.05. RESULTS: Solid fusion was achieved in 63 patients (95.5%). Fusion was noted in 100% of the allograft patients, whereas 90.3% of the autograft cases achieved fusion. No statistically significant difference was noted between allograft to autograft with regard to fusion rate (P > 0.05). Three patients developed nonunions (1 smoker; 2 nonsmokers) and entailed Orion instrumentation. In the one patient who was a nonsmoker with a nonunion, slight screw penetration into the involved and uninvolved interbody spaces was noted. No other intraoperative, postoperative, or radiographic complication was noted. All of the nonunions occurred early in the series. Postoperatively, excellent results were reported in 19.7%, good results in 71.2%, and fair results in 9.1% of the patients. Satisfactory clinical outcome was noted in all nonunion patients. A nonstatistically significant difference was noted with regard to clinical outcome of fused and nonfused patients, demographics, and the presence of a work-related injury (P > 0.05). The impact of smoking was not a factor influencing fusion or clinical outcome in this series (P > 0.05). A statistically significant difference was noted in plate-type on fusion rate (P < 0.05). CONCLUSION: A 100% and 90.3% radiographic fusion rate was obtained for allograft and autograft in one-level ACDF procedures with rigid anterior plate fixation, respectively. Although autograft achieved a higher incidence of nonunion than allograft, this may be attributed to the use of autograft early in the experience of plate application and fixation in this series. The effects of smoking were not found to be a significant factor influencing fusion in these plated patients. In 90.9% of the patients, excellent and good clinical outcome results were reported. The use of allograft in one-level ACDF with rigid plate fixation yields similar and high fusion rates as autograft. The use of allograft bone eliminates complications and pitfalls associated with autologous donor site harvesting. However, the use of autograft is a viable alternative to avoid the risk of infection, disease transmission, and histocompatibility differences associated with allograft. The use of allograft or autograft bone in properly selected patients for one-level ACDF with rigid anterior plate fixation can result in high fusion rates with excellent and good clinical outcomes.

Adult↗
PubMed2005

A prospective cohort analysis of adjacent vertebral body bone mineral density in lumbar surgery patients with or without instrumented posterolateral fusion: a 9- to 12-year follow-up.

STUDY DESIGN: A prospective, cohort study of 11 patients who underwent either a posterior lumbar spinal fusion with instrumentation (n = 7) or a lumbar laminotomy and discectomy alone (n = 4) and who were evaluated by dual energy radiograph absorptiometry (DEXA) to determine bone mineral density (BMD) at the adjacent three cephalad vertebral levels. OBJECTIVES: To determine long-term BMD changes that occur at the adjacent three levels above an instrumented posterolateral lumbar fusion or an isolated laminotomy and lumbar discectomy. SUMMARY OF BACKGROUND DATA: No long-term prospective study has evaluated the affects of instrumented lumbar fusions on bone remodeling at adjacent vertebral levels. Several studies in animals and humans have reported a decrease in BMD at the adjacent level during the first 6 months after spinal fusion with a return to baseline at 1-year follow-up in up to 60% of patients. METHODS: DEXA was performed initially at a mean postoperative follow-up of 4 years (range, 2.3-5.5 years) and again at a mean of 10.8 years (range, 9.1-2.4 years). Eleven patients were divided into two groups: laminotomy and discectomy (n = 4) and instrumented posterior spinal fusion (n = 7). All patients underwent surgical procedures at the L4-L5 or L5-S1 levels with DEXA analysis being performed on the adjacent three cephalad levels. The discectomy group (mean age, 57.8 years) underwent lumbar hemilaminotomy without fusion whereas the other group (mean age, 60 years) underwent pedicle-screw instrumentation and posterolateral lumbar fusion. Peripheral sites, including the femoral neck, were included in the DEXA analysis to normalize for individual differences in bone mineral metabolism. RESULTS: At the mean 10.8-year follow-up, the fusion group was noted to have at the adjacent level, two levels cephalad, and three levels cephalad normalized BMDs of 1.47, 1.39, and 1.27, respectively. A 14.8%, 10.8%, and 9.5% increase respectively in normalized BMD was observed when compared with the mean 4-year fusion values (P < 0.05). This increase was also noted on comparative T-score, Z-score, and absolute BMD values (P < 0.05). The discectomy group when evaluated revealed no statistically significant change from the mean 4 to 10.8-year follow-up (BMD, normalized BMD, T-score, Z-score). No statistically significant difference was noted in hip BMD at the mean 4-year and 10.8-year follow-up (1.05 versus 1.03), suggesting that the effects were local. CONCLUSIONS: The local BMD adjacent to an instrumented lumbar fusion is increased at a mean of 10.8-years after surgery. There is a gradual decrease in BMD changes with increasing distance from the fusion level. Alterations in fusion site biomechanics and modulus mismatch between the host bone and the spinal instrumentation most likely result in chronic, localized bone remodeling with an increased BMD that decreases the greater the distance from the fusion mass.

Bone Density↗
PubMed2005

Multilevel en bloc spondylectomy and chest wall excision via a simultaneous anterior and posterior approach for Ewing sarcoma.

STUDY DESIGN: A case study of a patient with Ewing sarcoma of T8 and T9 with paravertebral and chest wall involvement, who underwent neoadjuvant chemotherapy and subsequent multilevel en bloc spondylectomy and chest wall excision using a simultaneous anterior and posterior approach. OBJECTIVE: To show the feasibility of treating Ewing sarcoma of the thoracic spine with paravertebral and chest wall extension by multiagent chemotherapy followed by a multilevel en bloc spondylectomy and chest wall excision using a simultaneous anterior and posterior approach. SUMMARY OF BACKGROUND DATA: Ewing sarcoma is a primary malignant bone tumor that occasionally involves the spinal column. Most patients with Ewing sarcoma of the spine are treated with systemic chemotherapy followed by definitive local control. Radiation therapy is the usual mode of local control in these patients because the spinal column has historically been considered a surgically inaccessible site where wide surgical margins are difficult to obtain. However, en bloc spondylectomy techniques have been described that can probably further decrease the risk of local recurrence, thereby minimizing or even eliminating the need for radiation therapy. To our knowledge, a combined en bloc spondylectomy and chest wall excision in a patient with Ewing sarcoma in the spine has not been previously reported. METHODS: Neoadjuvant chemotherapy consisting of vincristine, doxorubicin, and cyclophosphamide was administered. After completion of the chemotherapy, an en bloc spondylectomy of T8 and T9 with removal of the chest wall was achieved using a simultaneous anterior and posterior approach to the spine. A stackable carbon fiber cage filled with autograft and allograft bone was inserted between T7 and T10. The spine was stabilized with anterior and posterior instrumentation. The chest wall was reconstructed with contoured polymethylmethacrylate and polypropylene (Marlex, Textile Development Associates, Inc., Franklin Square, NY) mesh. RESULTS: The patient maintained normal neurologic function, and pain was lessened. The margins were free of tumor, and tumor necrosis was 100%. After surgery, radiotherapy was not administered. No local tumor recurrence or distant metastases were evident at the last follow-up. Balance in the coronal and sagittal planes was maintained. The patient has returned to work and resumed normal activities of daily living. CONCLUSIONS: Multilevel en bloc spondylectomy and chest wall excision performed using a simultaneous anterior and posterior approach is a safe and effective technique that may be used to achieve adequate margins in select patients with malignant tumors involving the thoracic spine and chest wall. This technique can eliminate the need for radiation therapy in patients with Ewing sarcoma and probably decreases the risk of local recurrence compared with radiation therapy alone.

Adult↗