Faculty Bibliography

ABSTRACT: Study Design. Independent review and classification of therapeutic procedures performed on cadavers by surgeons blinded to purpose of study.Objective. The objective of this study is to determine the rate of facet violation with the placement of percutaneous pedicle screws.Summary of Background Data. Improvements in percutaneous instrumentation and fluoroscopic imaging have led to a resurgence of percutaneous pedicle screw insertion in lumbar spine surgery in an attempt to minimize many of the complications associated with open techniques of pedicle screw placement. Rates of pedicle breech and neurologic injury resulting from percutaneous insertion are reportedly similar to those of open techniques. Postoperative pain due to impingement and instability is believed to result from violation of the facet capsule or facet joint. To the authors' knowledge, however, the rate of facet injury associated with the placement of percutaneous pedicle screws is unreported in the literature.Methods. Percutaneous pedicle screw placement was performed on four cadaveric specimens by four certified orthopaedic surgeons who had clinical experience in the procedure and who were blinded to the study's purpose. The surgeons were instructed to place pedicle screws from L1-S1 using their preferred clinical techniques and a 5.5-mm screw system with which they were all familiar. All surgeons utilized one OEC C-arm for fluoroscopic imaging. After insertion, two independent spine surgeons each reviewed and classified the placement of all facet screws.Results. A total of 48 screws were inserted and classified. The placement of 28 screws (58%) resulted in violation of facet articulation, with 8 of these screws being intra-articular. Interobserver reliability of the classification system was 100%.Conclusion. Percutaneous pedicle screw placement may result in a high rate of facet violation. Facet injury can be reliability classified and therefore, perhaps, easily prevented

STUDY DESIGN.: Retrospective cohort. OBJECTIVE.: To compare survivorship after cement augmentation of refractory osteoporotic vertebral compression fractures (OVCFs) with traditional inpatient pain management and bracing. SUMMARY OF BACKGROUND DATA.: OVCFs can cause debilitating pain and functional decline necessitating prolonged bed rest and high-dose narcotics. Vertebroplasty and kyphoplasty are cement augmentation procedures used to control pain and restore function in patients with OVCF's that are refractory to conservative treatment. Early mobilization is associated with improved survival after other fractures in elderly patients. METHODS.: A university hospital database was used to identify all participants treated with primary diagnosis of OVCF between 1993 and 2006. Chart review and imaging studies were used to confirm demographics, comorbidities, diagnosis, and treatment. Survival time was determined using hospital data, national death indices and patient follow-up. Exact Fisher tests, Mann-Whitney tests, and proportional hazards regression models with Kaplan-Meier plots compared patients treated with cement augmentation with controls treated with inpatient pain management and bracing. Patients with high-energy trauma, tumors or age more than 60 years were excluded. RESULTS.: Within the past 12 years, 46 patients treated with cement augmentation and 129 matched controls met inclusion criteria. They did not differ with respect to age, sex, and comorbidities. A significant survival advantage was found after cement augmentation compared with controls (P < 0.001; log rank), regardless of comorbidities, age, or the number of fractures diagnosed at the start date (P = 0.565). Controlling simultaneously for covariates, the estimated hazard ratio associated with cementation was 0.10 (95% confidence interval [CI] = 0.02-0.43; P = 0.002) for year 1, 0.15 (95% CI = 0.02-1.12; P = 0.064) for year 2, and 0.95 (95% CI = 0.32-2.79; P = 0.919) for subsequent follow-up. The number of OVCFs at the start time of treatment did not affect survival benefit of cementation (P = 0.44). CONCLUSION.: Cement augmentation of refractory OVCF improves survival for up to 2 years when compared with conservative pain management with bed rest, narcotics, and extension bracing, regardless of age, sex, and number of fractures or comorbidities. Therefore, aggressive management should be considered for refractory OVCFs with intractable back pain

BACKGROUND CONTEXT: Many Americans seek and are influenced in their decision making by medical information on the Internet. Past studies have repeatedly found information on most medical Web sites to be deficient and of low quality. Physicians must remain aware of the quality and reliability of the information available on the Internet for patient education purposes. PURPOSE: To assess quality and authorship of Internet Web sites regarding a common cervical spine disorder, cervical disc herniation. STUDY DESIGN: The present study is a systematic quality assessment survey of Web sites concerning cervical disc herniation. METHODS: Fifty relevant and unique sites were identified. The five most popular search engines were used to identify 100 Web sites using the search term, 'cervical disc herniation.' Using a validated technique, three orthopedic surgeons independently generated content quality scores and accuracy scores, then integrated into a single final total summary score for each Web site. RESULTS: Four of the five identified top-scoring Web sites were found to be commercial and one was academic. Most of the Web sites were found to be physician sponsored, followed by academic and commercial. CONCLUSIONS: There is wide variability in Web site quality, with most of the Web sites failing to be sufficiently comprehensive and accurate. Physicians treating patients with cervical disc herniation must remain vigilant in guiding their patients to proper information on the Internet

STUDY DESIGN: Case series. OBJECTIVE: Report long-term outcomes, complications, and surgical technique of cervical myopathy (CM) patients treated with posterior instrumented, cervico-thoracic (C-T) fusions. SUMMARY OF BACKGROUND DATA: CM is a rare, progressive, debilitating condition where weakness of neck extensor muscles results in a dropped head deformity (DHD), or severe flexible, cervico-thoracic kyphosis. Treatment algorithms are currently based on small case reports and only 1 patient's short-term surgical outcome. METHODS: Re-examination at follow-up, chart review, and radiographic analysis was carried out for all CM patients with DHD treated by the senior author. Additional outcome measures included Odom criteria, verbal rating scores for pain, and patient satisfaction ratings. Patients with less than 2-years follow-up, previous cervical spine surgery or intrinsic, structural spinal deformities were excluded. RESULTS: Nine CM patients met the study inclusion criteria with average follow-up of 6 years (range, 2-17 years) and average age 67 years. Four primary and 5 secondary myopathies after radiotherapy underwent deformity correction and posterior arthrodesis with instrumentation from the second cervical level to the upper thoracic spine. Patient presentation, deformity correction, and surgical techniques are described. All pain ratings improved, satisfaction was excellent in 7 and fair in 2 patients, and Odom scores were good to excellent in 7 and fair in 2 patients. Shoulder weakness remained equivalent or improved after surgery and all ambulated independently, though 1 continued to use a walker. Eleven postoperative complications are described. CONCLUSION: Surgical correction with posterior, instrumented C-T spinal fusion is associated with high patient satisfaction rates in CM patients with DHD. Complications are frequent but do not diminish long-term outcomes. New rod and screw instrumentation with bone morphogenic protein may improve arthrodesis and correction

RATIONALE AND OBJECTIVES: The optimal advanced imaging method for detection and characterization of posterior tibialis tendon (PTT) tears is unclear. The purpose of this study was to investigate the utility of ultrasonography (US) and MR imaging in the detection of surgically created PTT tears in cadavers. MATERIALS AND METHODS: This was a prospective blinded study in which 16 fresh cadaveric foot and ankle specimens (3 men, 13 women; average age at death 83.9 years; age range 71-96 years) were scanned with both US and MR imaging before and after the surgical creation of 64 variable length longitudinal tears of the PTT. Ultrasonography was performed with a 12 MHz linear transducer with independent interpretations of static and dynamic studies separately by two blinded and experienced musculoskeletal radiologists. MR imaging was performed at 1.5 T with a standard transmit-receive extremity coil using axial, sagittal, coronal T1-weighted (TR 600, TE 20), and axial fast spin echo proton density and T2-weighted (TR 3000, TE 161/20, ETL 12) images. MR images were reviewed independently by two experienced musculoskeletal radiologists who were blinded to the status of the PTT. RESULTS: Sensitivity, specificity, and accuracy of MR imaging in the diagnosis of PTT tears were 73%, 69%, and 72%, respectively. Dynamic US interpretation yielded values of 69% sensitivity, 81% specificity, and 72% accuracy. Static US interpretation was less reliable than dynamic interpretation, and the only significance of static imaging was a high specificity (94%) for detection of longitudinal tears. The positive predictive value (PPV) for MR imaging and US was 88% and 92% respectively, and the negative predictive value (NPV) was 46% for both MR imaging and US. CONCLUSION: Our results suggest that US and MR imaging perform at the same level for the detection of surgically created longitudinal PTT tears in a cadaveric model. US has a higher specificity compared with MR imaging

Cricothyrotomy is indicated for patients who require an immediate airway and in whom orotracheal or nasotracheal intubation is unsuccessful or contraindicated. Cricothyrotomy is considered safe with cervical spine (c-spine) injury; however, the amount of c-spine movement that occurs during the procedure has not been determined. In this experimental study, an established cadaver model of c-spine injury was used to quantify movement during cricothyrotomy. A complete C5--6 transection was performed by using an osteotome on 13 fresh-frozen cadavers. Standard open cricothyrotomy was performed on each cadaver, with c-spine images recorded in real time on fluoroscopy, then transferred to video and Kodachrome still images. Outcome measures included movement across the C5--6 site with regard to angulation expressed in degrees of rotation and linear measures of axial distraction and anterior-posterior (AP) displacement expressed as a proportion of C5 body width. Data were analyzed by using descriptive statistics to determine mean change from baseline in each of three planes of movement. Significance was assumed if 95% confidence intervals did not include zero. A significant amount of movement was observed with regard to AP displacement (6.3% of C5 width) and axial distraction (-4.5% of C5 width, indicating narrowing of the intervertebral space). These correspond to 1--2 mm AP displacement and less than 1 mm axial compression. No significant angular displacement was observed. In conclusion, cricothyrotomy results in a small but significant amount of movement across an unstable c-spine injury in a cadaver model. This degree of movement is less than the threshold for clinical significance

STUDY OBJECTIVE: Orotracheal intubation (OTI) is commonly used to establish a definitive airway in major trauma victims, with several different cervical spine immobilization techniques and laryngoscope blade types used. This experimental, randomized, crossover trial evaluated the effects of manual in-line stabilization and cervical collar immobilization and 3 different laryngoscope blades on cervical spine movement during OTI in a cadaver model of cervical spine injury. METHODS: A complete C5-C6 transection was performed by using an osteotome on 14 fresh-frozen cadavers. OTI was performed in a randomized crossover fashion by using both immobilization techniques and each of 3 laryngoscope blades: the Miller straight blade, the Macintosh curved blade, and the Corazelli-London-McCoy hinged blade. Intubations were recorded in real time on fluoroscopy and then transferred to video and color still images. Outcome measures included movement across C5-C6 with regard to angulation expressed in degrees of rotation and axial distraction and anteroposterior displacement with values expressed as a proportion of C5 body width. Cormack-Lehane visualization grades were also recorded as a secondary outcome measure. Data were analyzed by using multivariate analysis of variance to test for differences between immobilization techniques and between laryngoscope blades and to detect for interactions. Significance was assumed for P values of less than.05. RESULTS: Manual in-line stabilization resulted in significantly less movement than cervical collar immobilization during OTI with regard to anteroposterior displacement. Use of the Miller straight blade resulted in significantly less movement than each of the other 2 blades with regard to axial distraction. The Cormack-Lehane grade was significantly better with manual in-line stabilization versus cervical collar immobilization; no differences were observed between blades. CONCLUSION: Manual in-line stabilization results in less cervical subluxation and allows better vocal cord visualization during OTI in a cadaver model of cervical spine injury. The Miller laryngoscope blade allowed less axial distraction than the Macintosh or Corzelli-London-McCoy blades. The clinical significance of this degree of movement is unclear