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Dhruv B Pateder

Publications and source records attributed to Dhruv B Pateder.

10 recordsLinked to original sources
PubMed2006

Spinal fusion after revision surgery for pseudarthrosis in adult scoliosis.

STUDY DESIGN: A retrospective study. OBJECTIVE.: To decipher the incidence, characteristics, functional outcomes, and complications of spinal fusion after revision surgery for recurrent pseudarthrosis in adult patients with scoliosis. SUMMARY OF BACKGROUND DATA: While the rate of spinal fusion has been examined in the past, there have been no studies that have examined the incidence, characteristics, functional outcomes, and complications of spinal fusion after pseudarthrosis repair in adult patients with scoliosis. MATERIALS AND METHODS: A total of 132 patients with failed spinal fusion surgery for adult scoliosis and painful pseudarthroses were studied. Each patient had an average of 3.7 spinal surgeries before undergoing revision at our institution. In addition to clinical assessment and imaging studies, pseudarthrosis was confirmed intraoperatively in all patients. All patients underwent reinstrumentation and fusion along with adjunctive procedures as needed. Spinal fusion was assessed clinically and radiographically after surgery for a minimum of 40 months. Subjective functional outcomes and complications associated with the procedures were also studied. RESULTS: The overall incidence of spinal fusion after revision surgery for pseudarthrosis in adult scoliosis was 90%. There was a propensity for pseudarthrosis to recur at the thoracolumbar and lumbosacral junctions. Increasing thoracolumbar kyphosis and loss of sagittal balance were significant risk factors for recurrent pseudarthrosis after revision surgery (mean thoracolumbar kyphosis of 23 degrees and mean sagittal balance of 7.9 cm anteriorly associated with persistent pseudarthrosis). Additionally, patients with multiple preoperative sites of pseudarthroses were at a higher risk for continued pseudarthrosis after surgery. Cigarette smoking, age, and surgical approach did not have any significant correlation with pseudarthrosis. Seventy-two percent of patients were satisfied with the outcome and 80% would have chosen to undergo surgery again if necessary. Thirty-three percent of patients who underwent surgery had some complication related to the surgery. CONCLUSION: Revision surgery for pseudarthrosis repair in adult scoliosis is most successful at attaining fusion when thoracolumbar and overall sagittal alignment are restored as much as possible.

Adult↗
PubMed2006

Tip of the trade: a method of splinting for surgeons.

Mallet fingers are difficult to treat, especially in surgeons, who need to sterilize their hands continuously and who have constant strains placed on their fingers. We successfully treated a nondominant, fifth-digit, nonbony mallet finger in a surgical resident with a splint method composed of a bent, semitubular, small-fragment plate and Steri-strips (3-M, St. Paul, MN). This splinting method allowed the resident to continue performing surgeries while the injury healed.

Adult↗
PubMed2005

Lumbar nerve root palsy after adult spinal deformity surgery.

STUDY DESIGN: A retrospective study was conducted to investigate the incidence and prognosis of postoperative lumbar nerve root palsy after surgical treatment for adult spinal deformity. OBJECTIVE: To decipher the incidence of postoperative lumbar nerve root palsy and recovery in 361 adult spinal deformity patients who underwent 407 spinal fusion surgeries. SUMMARY OF BACKGROUND DATA: Although lumbar nerve root palsy is a known complication of spinal surgery, there are no large studies that have examined its incidence or prognosis. METHODS: Three hundred and sixty-one consecutive patients who underwent 407 procedures for adult deformity spinal surgery were reviewed. Patients in this study did not have spinal cord injury or nerve root compression on the postoperative imaging study (obtained for change in neurologic examination). The incidence of nerve root palsy was based on postoperative muscle strength, which was followed for a minimum of 3 and an average of 7 years. RESULTS: The overall incidence of lumbar nerve root palsy was 2.9% with a 1.4% incidence in primary and 3.8% incidence in revision surgery. The incidence was 0.9, 1.5, and 7.4% for fusion of <5 levels, 5 to 10 levels, and >10 levels, respectively. The incidence of nerve root palsy for posterior only, same day anterior-posterior, and staged posterior was 1.3, 3, and 7.2%, respectively. While L5 was the most commonly injured nerve root, all other lumbar nerve roots were also involved. There were no S1 injuries. Although there was some recovery in most injuries, Grade IV injuries had the best recovery at 1-year follow-up. CONCLUSION: Patients with increasingly complex spinal deformities are at a higher risk for postoperative lumbar nerve root palsy. These injuries can be treated nonoperatively when there is no identifiable cause on postoperative imaging studies.

Adult↗
PubMed2005

Cervical spine trauma.

Traumatic injuries to the cervical spine are often difficult to detect and are associated with substantial morbidity and mortality. Along with standard trauma radiographs, a thorough physical examination and meticulous documentation are of the utmost importance because many neurologic injuries evolve over time. Although many injuries to the cervical spine can be treated nonoperatively, any injuries with neurologic deficits, instability, or ligamentous injury require instrumentation and fusion. It is crucial to recognize injuries to the cervical spine and the different treatment options. Computed tomography can be very helpful in defining the bony injury and evaluating the spinal canal, whereas magnetic resonance imaging can better evaluate the spinal cord and assess ligamentous injury.

Arthrodesis↗
PubMed2005

Compartment syndrome: time from diagnosis to fasciotomy.

A definitive safe time to fasciotomy for compartment syndrome has not been established. Therefore, the records of 28 patients who had a fasciotomy for compartment syndrome at two trauma centers (18 level I, 10 level II) were reviewed to determine time from diagnosis to fasciotomy and clinical outcome. Average times at the two trauma centers (level I: 160 minutes, range, 50-315 minutes; level II: 105 minutes, range, 51-185 minutes) were significantly different. Ten patients (5 level I, 5 level II) with an average time from diagnosis to fasciotomy of 122 minutes (range, 70-185 minutes) sustained residual deficits. There was no correlation between time from diagnosis to fasciotomy and residual deficits. A time from diagnosis to fasciotomy as short as 70 minutes was associated with residual deficit, but a time as long as 315 minutes (patient with deficits) was associated with no functional deficits.

Adult↗
PubMed2002

Lead alters parathyroid hormone-related peptide and transforming growth factor-beta1 effects and AP-1 and NF-kappaB signaling in chondrocytes.

The skeletal system is an important target for lead toxicity. One of the impacts of lead in the skeleton, the inhibition of axial bone development, is likely due to its effect on the normal progression of chondrocyte maturation that is central to the process of endochondral ossification. Since little is known about the effect of lead on chondrocyte function/maturation, its impact on (1) growth factor-induced proliferation, (2) expression of maturation-specific markers type X collagen and BMP-6, and (3) the activity of AP-1 and NF-kappaB was examined in chick growth plate and sternal chondrocyte models. Exposure to lead alone (1-30 microM) resulted in a dose-dependent inhibition of thymidine incorporation in growth plate chondrocytes. Lead also blunted the stimulation of thymidine incorporation by parathyroid hormone-related peptide (PTHrP) and transforming growth factor-beta1 (TGF-beta1), two critical regulators of chondrocyte maturation. Lead (1 and 10 microM), TGF-beta1 (3 ng/ml) and PTHrP (10(-7) M) all significantly inhibited the expression of type X collagen, a marker of chondrocyte terminal differentiation. However, when in combination, lead completely reversed the inhibition of type X collagen by PTHrP and TGF-beta1. The effect of lead on BMP-6. an inducer of terminal differentiation. was also examined. Independently, lead and TGF-beta1 were without effect on BMP-6 expression, but PTHrP significantly suppressed it. Comparatively, lead did not alter PTHrP-mediated suppression of BMP-6, but in combination with TGF-beta1. BMP-6 expression was increased 3-fold. To determine if lead effects on signaling might play a role in facilitating these events, the impact of lead on NF-kappaB and AP-1 signaling was assessed using luciferase reporter constructs in sternal chondrocytes. Lead had no effect on the AP-1 reporter, but it dose-dependently inhibited the NF-kappaB reporter. PTHrP, which signals through AP-1, did not activate the NF-kappaB reporter and did not affect inhibition of this reporter by lead. In contrast, PTHrP activation of the AP-1 reporter was dose-dependently enhanced by lead. These findings, which establish that chondrocytes are important targets for lead toxicity, suggest that the effects of lead on bone growth are derived from its impact on the modulation of chondrocyte maturation by growth factors and second messenger signaling responses.

Animals↗
PubMed2002

Parathyroid hormone-related Peptide expression in cartilaginous tumors.

Parathyroid hormone-related peptide is one of the most important regulators of chondrocyte proliferation. Although cartilaginous neoplasms express different collagens, including Types II and X, the pathogenesis of these tumors has not been elucidated. The current study examined the hypothesis that parathyroid hormone-related peptide is expressed in cartilaginous neoplasms and its level of expression may correlate with the proliferative rate of cartilaginous neoplasms with higher levels in more malignant tumors and lower levels in benign lesions. Two hundred thirty-four biopsy and resection specimens of benign and malignant cartilage tumors from 179 patients were retrieved from surgical pathology archival material and analyzed immunohistochemically using an antibody to human parathyroid hormone-related peptide. Most cartilaginous neoplasms had some level of expression of parathyroid hormone-related peptide, and tumors with a more proliferative phenotype had higher levels of parathyroid hormone-related peptide. Although benign lesions such as enchondromas and osteochondromas had low levels of parathyroid hormone-related peptide, malignant neoplasms such as extraskeletal myxoid chondrosarcomas, dedifferentiated chondrosarcomas, and mesenchymal chondrosarcomas expressed high levels of parathyroid hormone-related peptide. Parathyroid hormone-related peptide expression correlated with grade of malignancy in chondrosarcoma. Although there were highly significant differences between Grade I chondrosarcoma versus Grade II and Grade III lesions, the difference between Grade II and Grade III chondrosarcomas approached significance. Parathyroid hormone-related peptide may represent a new tumor marker with potential diagnostic use in classifying cartilaginous neoplasms.

Humans↗
PubMed2002

Role of pentoxifylline in preventing radiation damage to epiphyseal growth plate chondrocytes.

Radiation therapy plays an important role as part of multimodality treatment for a number of childhood malignancies. The damaging effects of radiation on bone formation in children have been well documented. Recent work suggests that the postirradiation increase in cytosolic calcium is probably responsible for the deleterious effects of radiation on growth plate chondrocytes because it causes a specific suppression of the mitogen PTHrP. Using an in vitro model of avian growth plate chondrocytes, this study demonstrates that pentoxifylline is effective in increasing basal PTHrP mRNA levels and partially preventing the radiation-induced decrease in PTHrP mRNA. This effect of pentoxifylline is probably due to its ability to lower basal levels of cytosolic calcium and the radiation-induced increase in cytosolic calcium in chondrocytes. Pentoxifylline also prevented the radiation-induced decreases in [3H]thymidine uptake and BCL2 and PTHrP receptor mRNA levels in chondrocytes. The effects of pentoxifylline appear to be specific for the PTHrP signaling pathway because it did not alter basal TGFB mRNA levels or TGFB mRNA expression in irradiated chondrocytes. The results of the current study suggest that by decreasing basal cytosolic calcium levels and curtailing the radiation-induced increase in cytosolic calcium levels in chondrocytes, pentoxifylline is able to sustain PTHrP signaling in chondrocytes and maintains the proliferative signal that is necessary to prevent chondrocytes from undergoing apoptosis.

Animals↗
PubMedDate not supplied

Lateral mass screw fixation for cervical spine trauma: associated complications and efficacy in maintaining alignment.

BACKGROUND CONTEXT: Many studies have documented the efficacy of lateral mass screws, but there are no studies examining the alignment maintenance capability and few large studies examining the complications associated with the use of these devices in cervical spine trauma. PURPOSE: To evaluate complications and alignment maintenance capability associated with lateral mass screw placement for cervical spine trauma by one surgeon at one institution. STUDY DESIGN: A retrospective chart and radiograph review of adult patients who underwent lateral mass screw fixation after traumatic injuries to the cervical spine. PATIENT SAMPLE: Of 34 consecutive patients with cervical spine injuries who were treated surgically at a level-I regional trauma center, 29 met the inclusion criteria and formed the study group. OUTCOME MEASURES: Sagittal alignment, screw placement, and fusion were assessed on postoperative radiographs. METHODS: Inclusion criteria included an unstable cervical vertebral fracture or a fracture-dislocation treated with posterior spine fusion and lateral mass instrumentation and a minimum follow-up of 24 months. A review of hospital charts, operative reports, clinic notes, and plain radiographs for the 29 patients was performed, with an emphasis on operative and postoperative complications and alignment maintenance. RESULTS: For 28 of the 29 patients, the mean change in sagittal alignment from the immediate postoperative to the most recent follow-up radiographic examination was 2 degrees (range, 0 degrees to 6 degrees ). Radiographically, there was one case of instrumentation/fixation failure and loss of sagittal alignment 3 months postoperatively. Other complications included one case of C5 nerve root injury and four wound infections. CONCLUSIONS: The use of lateral mass screws for traumatic injuries of the cervical spine is associated with excellent maintenance of alignment and minimal complications.

Adolescent↗