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Alvin H Crawford

Publications and source records attributed to Alvin H Crawford.

At least 19 recordsLinked to original sources
PubMed2005

Experience with combined video-assisted thoracoscopic surgery (VATS) anterior spinal release and posterior spinal fusion in Scheuermann's kyphosis.

STUDY DESIGN: Retrospective. OBJECTIVES: To determine whether anterior endoscopic release and posterior spinal fusion could achieve stable correction in Scheuermann's kyphosis. SUMMARY OF BACKGROUND DATA: The initial treatment of choice of Scheuermann's kyphosis is thoracic hyperextension and postural exercises and/or Milwaukee brace. Milwaukee bracing is most efficacious in the early stages when the curvature is flexible and in the skeletally immature. However, it is known that larger curves, vertebral wedging greater than 10 degrees, and skeletally mature patients will not usually respond to this treatment. Surgery is indicated in the skeletally immature with severe deformity where brace treatment has failed to prevent progression. Posterior spinal instrumentation can achieve adequate correction in the less rigid curves. However, the more rigid curves have been shown to be resistant to posterior spinal fusion alone, therefore needing anterior spinal release. METHODS: Between 1995 and 2001, 19 patients underwent video-assisted thoracoscopic surgery and posterior spinal fusion for the treatment of Scheuermann's kyphosis. The average age was 17.4 years with closed triradiate cartilage in all. Average follow-up was 2.7 years. An average of 8.3 discs were released anteriorly; an average of 13 levels were fused posteriorly. RESULTS: Average preoperative kyphosis was 84.8 degrees. Average postoperative kyphosis was 43.7 degrees. Average kyphosis at follow-up was 45.3 degrees. Only 1.6 degrees of correction loss was noted. No junctional kyphosis was present. Two patients developed pleural effusion; one required thoracocentesis. Two patients developed pneumothorax. One patient underwent revision surgery for inferior hook pullout. One required mechanical ventilation. CONCLUSIONS: Combined video-assisted thoracoscopic surgery release and posterior spinal fusion for the treatment of Scheuermann's kyphosis is a viable option for the treatment of the more severe and rigid curves.

Adolescent↗
PubMed2005

Endoscopic mechanical spinal hemiepiphysiodesis modifies spine growth.

STUDY DESIGN: An in vivo porcine model of progressive scoliosis as an inverse analog of a proposed method of early surgical treatment. OBJECTIVES: To test the hypothesis that scoliotic curvatures may be repeatedly created using anatomically based vertebral staples and thoracoscopic surgical procedures. SUMMARY OF BACKGROUND DATA: Staple hemiepiphysiodesis is an established method for treating knee deformities. Similar procedures have so far failed to arrest or correct deformities of the spine. While experimental studies continue to suggest that spine growth is modifiable, no prior clinically translatable method has been shown to clearly and consistently alter vertebral growth. METHODS: Custom spine staples were implanted into midthoracic vertebrae of seven skeletally immature normal pigs. Each staple spanned an intervertebral disc and two growth plates and was fixed to adjacent vertebrae with screws. The animals were anesthetized biweekly for radiography during the 8-week study period. Final radiographs were taken after spine harvest. Initial and final postoperative Cobb angles were compared statistically. RESULTS: Five animals completed the protocol with a weight increase of 142% in 8 weeks. Coronal plane curvatures increased significantly with time, from 0.8 (+/-1.8) to 22.4 (+/-2.8; P = 0.0001). On average, sagittal plane curvatures did not increase with time. CONCLUSIONS: Spinal hemiepiphysiodesis using an anatomically based implant and minimally invasive procedures repeatedly induced spine curvature in a normal porcine model. These techniques may slow, and perhaps even correct, early progressive spine deformity without long rod instrumentation or fusion.

Animals↗
PubMed2005

Video-assisted thoracoscopic surgery: the Cincinnati experience.

Video-assisted thoracoscopic surgery is an alternative to open thoracotomy. We analyzed our experience during a consecutive series of 100 patients who had this procedure and who were available for study at 3-year followup. Video-assisted thoracoscopic surgery was done on patients with the following diagnoses: idiopathic scoliosis (n = 49), neuromuscular spinal deformity (n = 15), Scheuermann kyphosis (n = 15), congenital and infantile scoliosis (n = 5), neurofibromatosis (n = 5), Marfan (n = 1), postradiation scoliosis (n = 1), and repair of pseudoarthrosis (n = 1). Four patients had excision of the first rib to treat thoracic outlet syndrome. One patient had excision of an intrathoracic neurofibroma and one a benign rib tumor. One had anterior arthrodesis after fracture-dislocation of the thoracic spine and another had anterior fusion for vertebral osteomyelitis. The average operative time for the thoracoscopic anterior release with discectomy and arthrodesis was 253 minutes. The average number of discs excised was 8. Final postoperative scoliosis and kyphosis corrections were 68% and 90%, respectively. Complications related to thoracoscopy occurred in eight patients. Video-assisted thoracoscopic surgery provides a safe and effective alternative to open thoracotomy in the treatment of thoracic pediatric spinal deformities.

Adolescent↗
PubMed2005

Anterior surgery in the thoracic and lumbar spine: endoscopic techniques in children.

Therapeutic modalities for disorders of the pediatric spine must include video-assisted thoracoscopy. The endoscopic approach to the spine has involved an evolutionary approach. What began as an isolated drainage of a vertebral abscess has continued as a method of single diskectomy, release of the anulus fibrosus with or without ligation of segmental vessels, rib resection for costoplasty, rib harvesting for intervertebral fusion and, most recently, insertion of correctional implants with or without spinal fusion. Video-assisted thoracoscopic surgery offers the potential to decrease surgical morbidity associated with traditional open procedures. The ability of video-assisted thoracoscopic surgery to achieve spinal release and the results of early outcomes and cost are comparable to those of open thoracotomy. The improvement in video technology with multichip cameras has significantly improved and enhanced the ability to identify structures in the chest through small incisions (portals). This technology allows spine surgeons to perform surgical intervention comparable to thoracotomy. Instead of using a 9- to 12-inch incision, four to five portals of approximately 2 cm are used; thus, the cosmetic efects of the scoliosis surgery are enhanced. The potential benefits of this procedure include diminished postoperative pain, decreased length of hospitalization, increased wound care, and early return to prehospital activities.

Adolescent↗
PubMed2004

The nuchal ligament restrains cervical spine flexion.

STUDY DESIGN: A biomechanical study using a cadaver model was conducted to define the function of the nuchal ligament in the restraint of flexion of the cervical spine. OBJECTIVE: To test the hypothesis that surgical resection of the nuchal ligament significantly reduces the structural restraints to cervical flexion. SUMMARY OF BACKGROUND DATA: Although previous studies have examined the role of the posterior ligaments and capsules on cervical stability, no prior study has quantified the biomechanical significance of the nuchal ligament. The clinical significance may include progressive loss of lordosis or even kyphosis after trauma or posterior surgical procedures such as laminectomy, laminoplasty, or tumor resection. METHODS: Cervical spines from the occiput to the first thoracic vertebra were harvested from 12 human cadavers. Specimens were tested under 3 conditions: all ligaments intact, after resection of the nuchal ligament, and then after additional resection of the supraspinous, interspinous, and yellow ligaments. Flexion moments were applied; load and displacement were measured. Changes in flexion range of motion and tangent stiffness between treatment conditions were statistically compared. RESULTS: The flexion range increased 28% after removing the nuchal ligament. After subsequent resections, the flexion range increased 52% compared with intact (P <0.005). Tangent stiffness decreased 27% after nuchal ligament resection; after all resections, stiffness was 35% lower than intact (P <0.05). CONCLUSION: Resection of the nuchal ligament increased the flexion range of motion and decreased stiffness in flexion. Injury to the nuchal ligament may increase the risk of cervical spine instability and malalignment.

Aged↗
PubMed2004

Early experiences with video-assisted thoracoscopic surgery: our first 70 cases.

STUDY DESIGN: Prospective consecutive series. OBJECTIVE: Analysis of the results and outcomes of patients treated with video-assisted thoracoscopic surgery for spinal pathology. SUMMARY OF BACKGROUND DATA: Video-assisted thoracoscopic surgery is an alternative to open thoracotomy. It has been suggested that the learning curve is substantial. The authors present their early experience in treating a variety of spinal pathologies with this technique. METHODS: Seventy cases were available at the 2-year follow-up. Video-assisted thoracoscopic surgery with the goal of anterior spinal release and fusion was carried out on patients with the following diagnoses: idiopathic scoliosis, neuromuscular spinal deformity, Scheuermann kyphosis, congenital and infantile scoliosis, neurofibromatosis, Marfan syndrome, postradiation scoliosis, and repair of pseudarthrosis. Three patients had excision of the first rib to treat thoracic outlet syndrome. Two patients had excision of intrathoracic neurofibroma and a benign rib tumor. One had anterior fusion following thoracic spine fracture-dislocation. RESULTS: The average operative time for the thoracoscopic anterior release with discectomy and fusion procedure was 256 minutes (range 150-405 minutes). The average number of discs excised was 8 (range 4-11 discs). The average operative time per disc was 32.5 minutes (range 20-45 minutes). The average blood loss during the thoracoscopic anterior release with diskectomy and fusion was 285 mL (range 150-405 mL). Final postoperative scoliosis and kyphosis corrections were 68% (range 41-91%) and 90% (range 47-100%), respectively. Complications related to thoracoscopy occurred in 3 patients. All deformity patients had evidence of anterior fusion radiographically. CONCLUSION: Video-assisted thoracoscopic surgery provides a safe and effective alternative to open thoracotomy in the treatment of thoracic pediatric spinal deformities. The procedure remains time consuming.

Adolescent↗
PubMed2004

Popliteal pterygium syndrome: implications for orthopaedic management.

Popliteal pterygium syndrome (PPS) is a rare genetic disorder that represents the association of a popliteal web with a combination of craniofacial, genitourinary, and extremity malformations. The management of fixed flexion deformity of the knee resulting from popliteal webbing, is of prime interest to the orthopaedist. The degree of popliteal webbing varies greatly. Due to this variable expression, various modalities to treat popliteal webbing exist. The presence of a short sciatic nerve in the free edge of a popliteal pterygium, is a limiting factor in surgical correction of this deformity. The popliteal web is typically the most difficult orthopaedic problem. The purpose of this report is to discuss the orthopaedic management of popliteal pterygium in eight patients.

Child↗
PubMed2004

Non-adjacent spondylolisthesis in ehlers-danlos syndrome.

To report a case of non-adjacent spondylolisthesis in a patient with Ehlers-Danlos syndrome. Clinical case analysis of a case of Ehlers-Danlos with non-adjacent spondylolisthesis. Review of this case reveals progressive lytic non-adjacent spondylolisthesis in a child with Ehlers-Danlos syndrome. There are no other reported cases of Ehlers-Danlos syndrome associated with non-adjacent spondylolisthesis. A review of the pathophysiology of the disease reveals possible mechanisms for this spinal abnormality.

Adolescent↗
PubMed2004

Legg-Calve-Perthes disease and thrombophilia.

BACKGROUND: Thrombophilia has previously been identified as a potential etiologic factor in Legg-Calve-Perthes disease. We prospectively studied the association between Legg-Calve-Perthes disease and coagulation abnormalities by comparing seventy-two children who had the disease with 197 healthy controls. METHODS: A nonselected, consecutive series of seventy-two patients with Legg-Calve-Perthes disease (mean age [and standard deviation], 6.6 +/- 2.6 years) was studied in their order of referral and compared with 197 healthy controls (mean age, 7.6 +/- 5.1 years). Assays were done for factor-V Leiden, prothrombin G20210A, methylenetetrahydrofolate reductase C677T, and plasminogen activator inhibitor-1 4G/5G gene mutations. Levels of anticardiolipin antibodies immunoglobulin G and M (IgG and IgM), homocysteine, protein C, protein S, antithrombin III, and plasminogen activator inhibitor-1 were also measured. RESULTS: The factor-V Leiden mutation was more common in the patients (eight of seventy-two) than in the controls (seven of 197) (chi-square = 5.7, p = 0.017). After we controlled for the false-discovery rate, the case-control difference remained significant (p = 0.017). The odds ratio for the development of Legg-Calve-Perthes disease in the presence of the factor-V Leiden mutation was 3.39 with a 95% confidence interval of 1.18 to 9.73. A high level of anticardiolipin antibodies (IgG and/or IgM) was found in nineteen of the seventy-two patients compared with twenty-two of the 197 controls (chi-square = 9.5, p = 0.002). After we controlled for the false-discovery rate, the case-control difference remained significant (p = 0.002). The odds ratio of patients with Legg-Calve-Perthes disease having one or more abnormalities in factor V, anticardiolipin antibody IgG, or anticardiolipin antibody IgM as opposed to normal values for all three variables was 3.29 (95% confidence interval, 1.73 to 6.24; p = 0.0003). CONCLUSIONS: Two thrombophilic risk factors, the factor-V Leiden mutation and anticardiolipin antibodies, are associated with Legg-Calve-Perthes disease, an association that may reflect causality. LEVEL OF EVIDENCE: Prognostic study, Level II-1 (retrospective study). See Instructions to Authors for a complete description of levels of evidence.

Adolescent↗
PubMed2004

Magnetic resonance imaging in the evaluation of infantile torticollis.

This retrospective study assessed the use of magnetic resonance imaging (MRI) in 58 infants with infantile torticollis. Eighteen patients had nonmuscular causes of torticollis (group 1); MRI identified lesions in 16 patients. Of 40 patients with a diagnosis of congenital muscular torticollis (group 2), 28 had a normal MRI. Five patients had asymmetry of the sternocleidomastoid without noticeable signal changes. Seven patients showd evidence of fibromatosis colli. Asymmetry of the posterolateral skull consistent with plagiocephaly was common. Magnetic resonance imaging did not alter treatment of group 2. Findings of compartment syndrome of sternocleidomastoid were inconsistent. Magnetic resonance imaging is not recommended for asymptomatic patients with infantile torticollis.

Female↗
PubMed2003

Orthopaedic implications in the management of pediatric vertebral and spinal cord tumors: a retrospective review.

STUDY DESIGN: Retrospective review of pediatric patients with vertebral and spinal cord tumors. OBJECTIVES: To identify clinical and radiographic features of diagnostic importance, and to evaluate the effectiveness of surgical treatment with respect to complications in pediatric patients with vertebral and spinal cord tumors. SUMMARY OF BACKGROUND: Vertebral and spinal cord tumors in children are uncommon and present a significant challenge in diagnosis, treatment, and management of complications. Because most signs and symptoms of these tumors are musculoskeletal in nature, it is imperative for orthopedic surgeons to be familiar with them. MATERIALS AND METHODS: Medical charts and radiographic records of 26 pediatric patients with documented vertebral and spinal cord tumors were reviewed retrospectively. RESULTS: There were 10 malignant and 16 benign tumors. Mean age at diagnosis was 10 years, and the male-to-female ratio was 1:1. Mean clinical follow-up was 25.8 months. The average delay in diagnosis was 10.9 months. The two most common reasons for presentation were pain (n = 20, 76%) and neurologic involvement (n = 14, 54%). Initial plain radiographs were positive in 72% of patients, whereas MRI showed the tumor in 96% of studies. Sixteen patients underwent spinal fusion after excision of the tumor. There were no perioperative deaths. Complications were common, with an average of 1.1 complications per patient. At latest follow-up, six patients had neurologic deficits, two patients had died, and one patient was terminally ill. CONCLUSION: Increased awareness of modes of presentation, use of modern imaging techniques, and an aggressive approach to spinal stabilization at the time of laminectomy should decrease morbidity in patients with vertebral and spinal cord tumors.

Adolescent↗
PubMed2003

Spinal deformity associated with carbohydrate-deficient glycoprotein syndrome (Jaeken's syndrome): a report of three cases.

STUDY DESIGN: Case reports are presented. OBJECTIVE: To report the association between carbohydrate-deficient glycoprotein syndrome Type 1a (CDGS Type 1a) and spinal deformity. SUMMARY OF BACKGROUND DATA: Carbohydrate-deficient glycoprotein syndrome Type 1a is an autosomal recessive metabolic disorder that may occur in association with spinal deformity. METHODS: Analyses of three cases are presented, including a review of the natural history of the disease. RESULTS: Three cases were reviewed in which spinal deformities developed in patients with CDGS Type 1a. Two patients required surgical correction of their spinal deformity, and one patient, at this writing, is undergoing conservative treatment. Before surgery, the pediatric hematology service was consulted regarding the patients' CDGD-related hypercoagulability. Of the two patients who underwent surgical correction, one had severe blood loss (7500 mL), and both cases were treated for infection via intravenous antibiotics. CONCLUSIONS: The incidence of CDGS Type 1a is 1 in 80,0000. Spinal deformity appears to be common in patients with CDGS Type 1a. Therefore, young patients with spinal deformities in combination with mental retardation, failure to thrive, abnormal fat distribution, and other symptoms of CDGS Type 1a should be assessed for this disorder, and patients with CDGS Type 1a should be screened also for spinal deformities. If abnormalities are identified early, treatment outcomes may be optimized.

Blood Loss, Surgical↗
PubMed2003

Osteogenic sarcoma of the rib: a case presentation and literature review.

STUDY DESIGN: A case report is presented. OBJECTIVES: Primary tumors of the rib are relatively uncommon in the adult population, and even more rare in children. A case of osteogenic sarcoma of the rib and a literature review are presented. SUMMARY OF BACKGROUND DATA: Osteogenic sarcoma represents approximately 30% of all malignant sarcomas diagnosed in the United States. A single case of osteogenic sarcoma of the rib has been reported in the literature involving a 9-year-old child. METHODS: Clinical data analysis. RESULTS: A 9-year-old white boy presented with a mass of the left posterior thorax. The initial chest radiograph showed a nonhomogeneous mass with calcifications adjacent to the 11th rib. The final diagnosis was osteogenic sarcoma. Chemotherapy was initiated. The patient underwent radical excision of the mass. Given the extent of the patient's resection, it was thought that he would be at high risk for the development of spinal deformity. He was placed in a TLSO brace (Bolt Systems, Orlando, FL) and followed closely. At 15 months after excision of his tumor, he was noted to have progression of a thoracolumbar scoliosis and significant kyphosis. At this writing, it has been 52 months since resection. The patient has no evidence of local recurrence or metastatic disease, and his spinal curvature remains stable. CONCLUSIONS: The patient's short-term (4-year) disease-free survival illustrates the efficacy of neoadjuvant chemotherapy and radical surgical resection. Patients with osteogenic sarcoma of the rib should be monitored closely for the development of spinal deformity if the required resection includes the vertebral column. Casting and bracing may help to limit progression of the deformity.

Bone Neoplasms↗