Drill and Fill Technique for the Treatment of Scaphoid Delayed Unions and Nonunions.

Background This article reviews the results of a surgical technique using three iterations of drilling , autologous cancellous bone grafting ( filling ), and use of an intraosseous compression screw for the treatment of nondisplaced or minimally displaced scaphoid delayed unions or nonunions. Methods Part 1-Cadaveric study: Three cadaveric scaphoids underwent stained cancellous bone graft packing and headless cannulated compression screw placement using a single iteration of drilling and graft packing. Three additional scaphoids were allocated to the triple "drill and fill" group, and underwent three iterations of drilling and graft packing before screw insertion. Graft particle distribution on mid-sagittal sections was assessed under fluorescence microscopy. Comparison of normalized areas between the single and triple "drill and fill" groups was performed using repeated measures ANOVA and Tukey's post hoc test. Part 2-Clinical study: Twelve patients with minimally displaced scaphoid delayed unions and nonunions treated between April 2007 and December 2013 with the triple "drill and fill" technique were included. The average follow-up was 60.4 weeks. Two fellowship-trained musculoskeletal radiologists independently reviewed images for fracture healing. Results By the histomorphometric analysis, there was improved autograft distribution along the screw tract, particularly within the proximal pole, with three iterations of drilling and filling. Clinically, 11 of 12 delayed unions and nonunions had healed. Conclusion Our results support the use of the "drill and fill" technique as an option for the treatment of select nondisplaced or minimally displaced scaphoid nonunions and delayed unions at the waist without avascular necrosis of the proximal pole. Level of Evidence This is a Level IV study.

The Relationship Between Body Mass Index and Fluoroscopy Time During Intraarticular Hip Injection: A Multicenter Cohort Study.

BACKGROUND: Higher body mass index (BMI) is associated with difficulty in obtaining imaging studies. While there is a small body of literature regarding the relationship between fluoroscopy time and BMI during injections for pain management, this has not been studied for intraarticular (IA) hip injections. Further, in academic training centers, trainee involvement may affect this relationship. OBJECTIVE: To determine the relationship between BMI and fluoroscopy time during IA hip injections, both with and without involvement of a trainee. STUDY DESIGN: Multicenter retrospective cohort study. SETTING: Three academic, outpatient musculoskeletal and pain medicine centers. METHODS: Patients who underwent fluoroscopically guided IA hip injections with encounter data regarding fluoroscopy time during the procedure and BMI were included. Mean and standard deviation fluoroscopy time were recorded. Comparisons were made between BMI categories of normal (18.5 - 24.9 kg/m2), overweight (25.0 - 29.9 kg/m2), and obese (greater than or equal to30.0 kg/m2). Statistical significance was set at P = 0.01 due to multiple comparisons. RESULTS: A total of 559 IA hip injections are represented in this cohort. Patients had a mean age of 58 (standard deviation [SD] 14) years and 63% were women. There was no significant difference in fluoroscopy time when comparing BMI categories (P = 0.02). However, when trainees were not involved in the injection, fluoroscopy times were significantly shorter with decreasing BMI category, with normal weight patients requiring the shortest fluoroscopy times (P = 0.01). LIMITATIONS: This study evaluated total fluoroscopy time, not radiation dose exposure per injection, which provides more direct and precise information with regard to provider and patient radiation exposure and overall safety. Future study of the impact of BMI on radiation dose during fluoroscopically guided IA hip injections is needed. CONCLUSIONS: Fluoroscopy times during IA hip injections increase with higher BMI categories in a statistically significant manner when performed by experienced clinicians but this relationship is not observed when injections are performed with a trainee in a teaching institution. This finding appears to be related to longer fluoroscopy time required to complete an IA hip injection in patients with lower BMI when a trainee is involved. KEY WORDS: Hip, injections, obesity, overweight, body mass index, fluoroscopy, radiation, pain.

Does Trainee Involvement in Fluoroscopic Injections Affect Fluoroscopic Time, Immediate Pain Reduction, and Complication Rate?

BACKGROUND: Patients have expressed concern about undergoing procedures involving trainees, even with direct attending physician supervision. Little literature has examined the effect of trainee involvement on patient outcomes. OBJECTIVE: We aimed to evaluate the effect of trainee involvement on patient complications, immediate pain reduction, and fluoroscopic time for different fluoroscopic injection types. DESIGN: Retrospective review. SETTING: Four academic outpatient institutions with Accreditation Council for Graduate Medical Education (ACGME)-accredited residency (physical medicine and rehabilitation, or anesthesiology) or fellowship (sports medicine or pain medicine) programs from 2000 to 2015. PATIENTS: All patients receiving fluoroscopically guided hip (HI), sacroiliac joint (SIJI), transforaminal epidural (TFEI), and/or interlaminar epidural injections (ILEI, performed at only 1 institution). METHODS: Outcome measures were examined based on the presence or absence of a trainee during the procedure. MAIN OUTCOME MEASUREMENTS: The primary outcome was the number of immediate complications, with secondary outcomes being fluoroscopic time per injection (FTPI) and immediate numeric rating scale percentage improvement. RESULTS: Trainees were involved in 67.0% of all injections (N = 7,833). Complication rates or improvements in numeric rating scale scores showed no significant differences with trainee involvement for any injection type (P > .05). Trainee involvement was associated with increased FTPI for ILEIs (18.2 ± 10.1 seconds with trainees versus 15.1 ± 8.5 seconds without trainees, P < .001), but not for HIs (P = .60) or SIJIs (P = .51). Trainee involvement with TFEIs was dependent on institution for outcome with respect to FTPI (P < .001), with 28.1 ± 17.9 seconds with trainees and 32.1 ± 22.1 seconds without trainees (P = 0.51). CONCLUSIONS: This large multicenter study of academic institutions demonstrates that trainee involvement in fluoroscopically guided injections does not affect immediate patient complications or pain improvement. Trainee involvement does not increase fluoroscopic time for most injections, although there is an institutional difference seen. This study supports the notion that appropriate trainee supervision likely does not compromise patient safety for fluoroscopically guided injections. LEVEL OF EVIDENCE: II.

Is There a Relationship Between Body Mass Index and Fluoroscopy Time During Cervical Interlaminar Epidural Steroid Injections?

BACKGROUND: The challenge of obtaining medical imaging in individuals with higher body mass index (BMI) is described, but there is minimal data regarding the relationship between BMI and fluoroscopy time during cervical interlaminar epidural steroid injection (CIESI). OBJECTIVE: To determine the relationship between BMI and fluoroscopy time during CIESI. METHODS: Retrospective cohort study of patients who underwent fluoroscopically guided CIESI between January 2014 and February 2015 at an academic pain medicine center. Fluoroscopy time data were collected. Comparisons based on analysis of variance were made between patients with normal (<25.0 kg/m 2 ), overweight (25.0-29.9 kg/m 2 ), and obese (≥30.0 kg/m 2 ) BMI. RESULTS: Of 399 procedure encounters, 366 had documented BMI and fluoroscopy time data and were included for analysis. Mean age (± SD) in this cohort was 53 ± 13 years, including 189 females (52%) and 205 first-time injections. Mean fluoroscopy time for all injections was 18 ± 10 seconds. Separated by categorical BMI class, the mean fluoroscopy time was 18 ± 9 seconds for normal weight patients, 17 ± 10 seconds for overweight patients, and 20 ± 11 seconds for obese patients, respectively. Post hoc analysis showed that fluoroscopy time was significantly longer only in obese compared with overweight patients ( P = 0.02). Trainee involvement and first-time vs repeat injection did not significantly alter fluoroscopy time ( P = 0.17 and P = 0.12, respectively). CONCLUSIONS: The findings of this study indicate that BMI does not appear to have a clinically significant impact on fluoroscopy time during cervical interlaminar epidural steroid injection procedures. Future study is needed to directly quantify radiation exposure in patients and practitioners, as well as the associated health risk.

The Impact of Body Mass Index on Fluoroscopy Time During Lumbar Epidural Steroid Injection; A Multicenter Cohort Study.

Objective: This study aimed to assess the relationship between BMI and fluoroscopy time during lumbar epidural steroid injections (LESIs) performed for lumbosacral radicular pain. Design: Multicenter retrospective cohort study. Setting: Three academic, outpatient pain treatment centers. Subjects: Patients who underwent fluoroscopically guided LESI. Methods: Mean and standard deviation (SD) fluoroscopy time were compared between patients with normal (18.5-24.9 kg/m2), overweight (25.0-29.9 kg/m2), and obese (≥30.0 kg/m2) BMI. Statistical significance was set at P=0.01 due to multiple comparisons. Results: A total of 2,930 procedure encounters were included, consisting of 598 interlaminar LESIs and 2,332 transforaminal LESIs. Fluoroscopy time was significantly longer in the obese patients compared to normal and overweight patients during interlaminar LESI (P < 0.01). Fluoroscopy time was significantly longer with each increasing BMI category in during transforaminal LESI (P < 0.01). These relationships remained when a trainee was involved (P < 0.01; P<0.01), during repeat injections (P < 0.01; P < 0.01), and during bilateral transforaminal LESIs (P < 0.01). While longer fluoroscopy times were required in high BMI categories during L5-S1 transforaminal LESI (P < 0.01), there was no relationship between fluoroscopy time and BMI during L4-L5 and S1 transforaminal LESI (P = 0.02; P = 0.13). Fluoroscopy time during interlaminar LESI compared to transforaminal LESI was significantly lower within all BMI categories (all P<0.01). Conclusions: The findings of this study indicate that fluoroscopy time is increased during interlaminar LESIs and during L5-S1 transforaminal LESIs in patients who are obese. These relationships are not affected by injection number, performance of bilateral injections, or trainee involvement. Further study is needed to determine if this increase in fluoroscopy time is indicative of a clinically significant associated increase in radiation dose.

Is There a Relationship Between Body Mass Index and Fluoroscopy Time During Sacroiliac Joint Injection? A Multicenter Cohort Study.

OBJECTIVE: To determine the relationship between BMI and fluoroscopy time during intra-articular sacroiliac joint (SIJ) injections performed for a pain indication. DESIGN: Multicenter retrospective cohort study. SETTING: Three academic, outpatient pain treatment centers. SUBJECTS: Patients who underwent fluoroscopy guided SIJ injection with encounter data regarding fluoroscopy time during the procedure and body mass index (BMI). MAIN OUTCOME MEASURE: Median and 25-75% Interquartile Range (IQR) fluoroscopy time. RESULTS: 459 SIJ injections (350 patients) were included in this study. Patients had a median age of 57 (IQR 44, 70) years, and 72% were female. The median BMI in the normal weight, overweight, and obese groups were 23 (IQR 21, 24), 27 (IQR 26, 29), and 35 (IQR 32, 40), respectively. There was no significant difference in the median fluoroscopy time recorded between these BMI classes (p = 0.45). First-time SIJ injection (p = 0.53), bilateral injection (p = 0.30), trainee involvement (p = 0.47), and new trainee involvement (trainee participation during the first 2 months of the academic year) (p = 0.85) were not associated with increased fluoroscopy time for any of the three BMI categories. CONCLUSIONS: Fluoroscopy time during sacroiliac joint injection is not increased in patients who are overweight or obese, regardless of whether a first-time sacroiliac joint injection was performed, bilateral injections were performed, a trainee was involved, or a new trainee was involved.

Transdermal scopolamine and perioperative anisocoria in craniofacial surgery: a report of 3 patients.

Postoperative nausea and vomiting (PONV) is a common complaint after plastic and reconstructive surgery. Transdermal scopolamine is a commonly used agent for prevention of PONV. Anisocoria from transdermal scopolamine use is an adverse effect that has not been reported in the plastic surgery literature. We present a series of 3 craniofacial patients in which ipsilateral mydriasis occurred and spontaneously resolved after removal of the scopolamine patch. Given the various causes and potentially grave implications of unilateral mydriasis, we discourage the use of transdermal scopolamine in craniofacial surgery, and especially in orbital surgery. However, if transdermal scopolamine is decided to be used for PONV prophylaxis, we recommend educating the patient, the operating room staff, and the surgical team regarding this potential adverse effect and to avoid finger-to-eye contamination after patch manipulation.

Biased assimilation, homophily, and the dynamics of polarization.

We study the issue of polarization in society through a model of opinion formation. We say an opinion formation process is polarizing if it results in increased divergence of opinions. Empirical studies have shown that homophily, i.e., greater interaction between like-minded individuals, results in polarization. However, we show that DeGroot's well-known model of opinion formation based on repeated averaging can never be polarizing, even if individuals are arbitrarily homophilous. We generalize DeGroot's model to account for a phenomenon well known in social psychology as biased assimilation: When presented with mixed or inconclusive evidence on a complex issue, individuals draw undue support for their initial position, thereby arriving at a more extreme opinion. We show that in a simple model of homophilous networks, our biased opinion formation process results in polarization if individuals are sufficiently biased. In other words, homophily alone, without biased assimilation, is not sufficient to polarize society. Quite interestingly, biased assimilation also provides a framework to analyze the polarizing effect of Internet-based recommender systems that show us personalized content.

Cold ischemia in microvascular breast reconstruction.

INTRODUCTION: A major drawback to microvascular free flap breast reconstruction is the length of operation-up to 9 hours or more for bilateral reconstruction. This takes a significant mental and physical toll on the surgical team, producing fatigue that may compromise surgical outcome. To facilitate the operation we have incorporated a period of cold ischemia of the flaps such that members of the surgical team can alternate a brief respite during the operation. METHODS: We retrospectively reviewed our series of microvascular free flap breast reconstructions performed over a four-year period in which cold ischemia of the flaps were induced. RESULTS: Seventy patients underwent free flap breast reconstruction with 104 flaps. Mean cold ischemia time for all flaps was 2 hours 36 min. Average rest time per surgeon per case was 35 min. Complications included two total flap losses (1.9%), one partial flap loss (1.0%), one anastomotic thrombosis (1.0%), two hematomas (1.9%), three fat necrosis (2.9%), and two delayed healing (1.9%). Statistical analysis revealed that the probability of complications is inversely related to cold ischemia time (P = 0.0163). CONCLUSION: Cold ischemia facilitates breast reconstruction by allowing the surgical team to alternate breaks during the operation. This helps reduce surgeon fatigue and is well tolerated by the flap. Thus, we believe that the use of cold ischemia is safe and advantageous in microvascular breast reconstruction.

Transverse Singapore flap for reconstruction of a congenital rectovaginal fistula in an 18-month-old infant.

Many different types of flaps have been used for reconstruction of rectovaginal fistulae. This is the first report of using a transverse Singapore flap for repairing a large 3 cm by 3-cm complex congenital rectovaginal fistula in an 18-month-old infant with VATER syndrome. A right transverse Singapore flap was used to reconstruct both the posterior wall of the vagina and the anterior wall of the rectum while simultaneously joining the 2 structures to the perineum. Despite minor postoperative delayed healing which resolved, the patient has maintained a functionally and cosmetically satisfactory result at 20-month follow-up. For complex rectovaginal fistulae reconstruction in the pediatric patient, the transverse Singapore flap is a reliable and viable option for the reconstructive surgeon.

Internally calibrated quantification of protein analytes in human serum by fluorescence immunoassays in disposable elastomeric microfluidic devices.

Herein we report on reliable reproducible quantification of protein analytes in human serum by fluorescence sandwich immunoassays in disposable PDMS microfluidic chips. The system requires 1,000 times less sample than typical clinical blood tests and is specifically shown to measure ferritin down to 250 pM in human serum. The in-built calibration method of spiking the serum with known concentrations of commercially available antigen avoids common sources of error and improves the reliability of the test results. The reported microfluidic system is an important new tool for fundamental scientific research, offering sensitive immunoassay measurements in small but complex biosamples. The system is also a further step towards comprehensive affordable "point-of-care" biomedical diagnostics.

Acute myocardial infarction and Friedreich's ataxia.

While cardiac disease is noted in 90% of patients with Friedreich's ataxia (FRDA), the finding of coronary artery disease is unusual. To the best of our knowledge only two cases of acute myocardial infarction (AMI) has been reported in patients with FRDA. Large vessel CAD has not been reported previously in patients with FRDA. We report a young patient with AMI and obstruction of large epicardial arteries.