Effect of patient-reported allergies on reverse total shoulder arthroplasty outcomes at over two years follow-up

Background/aims

Understanding the factors that lead to poor outcomes after reverse total shoulder arthroplasty (rTSA) is important to appropriate patient counseling. While patient-reported allergies (PRAs) have been shown to be associated with poorer outcomes after both TKA and THA, their effect on rTSA outcomes remains unclear. This study investigated the effect of zero, one, and two or more preoperative PRAs on clinical outcomes after rTSA at over two years follow-up in a cohort of fifty-two patients from our institution.

Methods

Patients who underwent rTSA and had a minimum follow-up time of two years were identified from an institutional database. Patients were split into cohorts of zero, one, and two or more PRAs. Range of motion (ROM) was assessed by degrees of forward elevation, external rotation, and internal rotation. Patient-reported outcomes (PROs) were assessed by the Visual Analog Scale (VAS), American Shoulder and Elbow Surgeon (ASES) score, and Simple Shoulder Test (SST) score.

Results

Fifty-two patients, 10 of whom reported one allergy and 11 of whom reported two or more allergies, were included in our analysis. Mean ROM and PROs improved after rTSA in each cohort. Differences in ROM and PROs between cohorts did not reach statistical significance; however, patients with PRAs tended to have worse preoperative forward elevation, VAS score, and ASES score. Two patients in the zero-allergy cohort required revision (6 %).

Conclusion

This study found no statistically significant difference in clinical outcomes among cohorts of patients with zero, one, or two or more preoperative PRAs after rTSA at over two years follow-up. However, patients with PRAs tended to have lower preoperative functional scores. We postulate that this may be the result of psychosomatic factors at play in these patients. PRAs should not dissuade patients or clinicians from pursuing rTSA.

Mid-term outcomes following reverse total shoulder arthroplasty

PURPOSE

The utilization of reverse total shoulder arthroplasty now exceeds the incidence of anatomic shoulder arthroplasty. Previous mid-to-long-term studies on rTSA have reported a decrease in shoulder function as follow-up increased. The purpose of this study was to provide data on mid-term outcomes and implant survival in a series focusing on reverse total shoulder arthroplasty.

MATERIALS AND METHODS

Demographic information such as age at surgery, revision surgery status, BMI, and smoking status were recorded. The clinical endpoints measured in this study were range of motion scores (forward elevation, external rotation, internal rotation) and patient reported outcomes (VAS, ASES, SST). Radiographic variables captured included preoperative glenoid morphology, humeral lucency, and glenoid loosening.

RESULTS

Fifty-six shoulders were included in this study. The overall mean age at surgery was 72.5 ± 7.2 years with an average follow-up time of 6.8 ± 3.5 years. The mean BMI was 28.1 ± 5.5. All measurements of range of motion saw significant and sustained improvements. Overall, forward elevation improved from 82° preoperatively to 133° postoperatively (p < 0.01). External rotation improved from 23° preoperatively to 36° (p < 0.01), while internal rotation improved from L3 to L1 (p = 0.05). ASES scores improved from 31 preoperatively to 70 postoperatively (p < 0.01). SST scores improved from 2 preoperatively to 7 (p < 0.01). VAS pain index scores improved from 6 to 2 following surgery (p < 0.01). Postoperative scapular notching was seen in 18 patients at final follow-up. Glenoid loosening was seen in 3 shoulders. Humeral loosening was seen in 18 shoulders. Tuberosity resorption was seen in 8 shoulders. The 5 year survival estimate was 98%, and the 10 year survival estimate was 83%.

CONCLUSION

In this series, we found that rTSA provides mid-term improvements in range of motion in patients while reducing pain levels. When considered together, this demonstrates that most patients undergoing rTSA can have excellent use of their shoulder from age at surgery to end-of-life.

Use of Spinal Anesthesia during Thoracic Endovascular Aortic Repair

BACKGROUND

The purpose of this study was to assess outcomes after spinal anesthesia (SA) versus general anesthesia (GA) in patients undergoing thoracic endograft placement and to evaluate the adjunctive use of cerebrospinal fluid drainage (CSFD) placement.

METHODS

A single-center retrospective review of patients that underwent thoracic endograft placement from 2001 to 2019 was performed. Patients were stratified based on the type of anesthesia they received: GA, SA or epidural, GA with CSFD, and SA with CSFD. Primary outcomes included 30-day mortality and length of stay (LOS). Baseline characteristics were analyzed with Student's t-test and Pearson's chi-squared test. Multivariate logistic regression analysis was performed to identify risk factors for 30-day mortality and longer LOS.

RESULTS

A total of 333 patients underwent thoracic endograft placement; 104 patients received SA, 180 patients received GA, 30 patients received GA and CSFD, and 19 patients received SA and CSFD. Of the total patients, 16.2% underwent thoracic endograft placement for type B aortic dissection, 3.3% for type A aortic dissection, and 12.3% for penetrating ulcer. The mean age of the study population was 68.7 years old. Patients undergoing SA were older with a mean age of 73.4 years versus 64.7 years for patients undergoing GA (P < 0.001). Spinal anesthesia (SA) was preferred in patients at high risk for GA (>75 years old: 52.9% vs. 33.3%, P < 0.001; renal comorbidities: 20.6% vs. 10.6%, P = 0.03, and current smokers: 26.7% vs. 9.6%, P < 0.001). Length of stay (LOS) was decreased in the SA group (4.29 days vs. 9.70 days, P < 0.001). There was a lower incidence of spinal cord ischemia in the SA group (1.0% vs. 2.2%, P = 0.44), as well as significantly decreased 30-day mortality (0% vs. 5.6%, P = 0.01), reintervention (19.2% vs. 26.8%, P = 0.02), and return to the operating room (6.8% vs. 12.7%, P = 0.02). Of the 19 patients that had SA + CSFD, there were no signs and symptoms of spinal cord ischemia and decreased incidence of perioperative complications (0% vs. 33.3%, P = 0.01). There was no difference in the risk for intraoperative complications, neurologic complications, or 30-day mortality between GA + CSFD patients versus SA + CSFD patients. Age >75 (P = 0.002), intraoperative complications (P < 0.001), and perioperative complications (P = 0.02) were associated with increased mortality after thoracic endograft placement per multivariate logistic regression analysis.

CONCLUSIONS

Spinal anesthesia (SA) in select high-risk patients was associated with reduced 30-day mortality, neurologic complications, and LOS compared to GA. The concurrent use of spinal drainage and SA had satisfactory results compared to spinal drainage and GA.

Most cited articles involving lacrosse since 1990 primarily focus on concussion and traumatic brain injury

OBJECTIVES

The purpose of this study was to identify the 50 most-cited publications relating to lacrosse since 1990 and conduct a bibliometric analysis of the identified studies.

METHODS

Clarivate Analytics Web of Science database was queried to identify all publication titles, abstracts, and keywords for the term 'lacrosse' on 9 June 2023. The resulting articles were sorted by total number of citations. Titles and abstracts were included based on their relevance to lacrosse. Once the 50 most cited articles were identified, each article was further analyzed to obtain author name, publication year, country of origin, journal name, article type, research topic, competition level, total number of citations, and the level of evidence. Citation density (total number of citations/years since publication) was calculated and recorded for each of the most-cited studies.

RESULTS

The 50 most-cited articles were cited 4237 of times with an average of 84 citations per article. The most cited article was cited 637 (15.0%) times. The articles came from 2 different countries, with the United States and Australia comprising 49 and 1 articles, respectively. All articles were published in English. The American Journal of Sports Medicine published the most articles (n = 21, 42.0%). The most studied topic was concussion/traumatic brain injury (n = 18) followed by studies assessing all injuries (n = 7). Collegiate-level lacrosse was the most studied level of competition (n = 22), while high school-level followed (n = 12).

CONCLUSIONS

The majority of the 50 most-cited articles related to lacrosse since 1990 focus on the prevalence, diagnosis and identification of concussion/traumatic brain injury in high school and collegiate-level athletes. These articles are predominantly epidemiological or cohort studies with Level III or IV evidence that almost unanimously originate from the United States.

The 50 most-cited articles in reverse shoulder arthroplasty

Background

Citation analyses have been used to understand the impact that a group of publications has on its field. As the techniques and indications of reverse total shoulder arthroplasty (RTSA) continue to expand, it is important to identify articles that can orient readers to the history, evolution, and current status of the body of RTSA literature. The purpose of this study was to identify and analyze the 50 most-cited articles related to RTSA.

Methods

Various Boolean queries were searched on the Clarivate Analytics Web of Science. Information collected included author name, publication year, country of origin, journal name, article type, total number of citations, and level of evidence.

Results

Top 50 most-cited articles amassed a total of 10,521 citations. The most-cited article was cited a total of 766 times. The most common study designs were case series (28) and cohort studies (9). Authors from the United States (24) contributed the most to included papers, followed by France (19) and Switzerland (8).

Discussion

The most-cited articles on RTSA are expert opinions, case studies, and cohort studies published by American authors. As RTSA continues to grow over the next decade, studies with higher levels-of-evidence may overtake articles included in this analysis.

Improved functional, radiographic and patient-reported outcomes at midterm follow-up for shoulder arthroplasty patients 75 years and older

Background

Current discussion centers around the appropriateness of shoulder arthroplasty in elderly patients, and whether anatomic and reverse total shoulder arthroplasty yield acceptable results in this population. The purpose of this study was to examine midterm outcomes in patients 75 years and older who underwent either procedure.

Methods

A retrospective review was performed on patients who underwent anatomic total shoulder arthroplasty (aTSA) or reverse total shoulder arthroplasty (rTSA) between 2000 and 2018. Inclusion criteria was patient age ≥75 years at time of surgery and ≥1 years postoperative follow-up. Primary outcomes were differences in Simple Shoulder Test (SST), American Shoulder and Elbow Surgeons (ASES) score, Visual Analog Scale (VAS) pain score, and range of motion. A secondary outcome was revision surgery.

Results

22 patients who underwent aTSA and 17 patients who underwent rTSA were included. Mean age at surgery was 79 and 80 in the aTSA and rTSA groups, respectively. Mean postoperative follow-up was 6.6 years across both cohorts. Anatomic TSA patients experienced improvements in VAS (7 preop vs. 1 postop; p < 0.001), ASES (16 vs. 75; p < 0.001), and SST (2 vs. 8; p < 0.001) scores. Reverse TSA patients also experienced improvements in VAS (7 vs. 1; p < 0.001), ASES (29 vs. 74; p < 0.001), and SST (1 vs. 7; p < 0.001) scores. Anatomic TSA patients experienced improved external rotation (17° vs. 53°; p < 0.001), forward elevation (108° vs. 155°; p < 0.001), and internal rotation (L5 vs. T10; p < 0.001). Reverse TSA patients experienced improved forward elevation (52° vs. 126°; p < 0.001). 21 aTSA patients (100%) and 16 rTSA patients (94%) experienced survival free from revision. 100% of aTSA and rTSA patients experienced survival free from loosening.

Conclusion

Both aTSA and rTSA can be performed in the elderly population with acceptable midterm outcomes, suggesting that implant survival and patient satisfaction have the potential to endure through the end of life.

Level of evidence

IV.

Revision Total Knee Arthroplasty for Ballistic Component Damage From an Intra-articular Missile

Gunshot wounds (GSWs) and total knee arthroplasty (TKA) are increasingly common, yet a GSW to a TKA is a rare injury. A 60-year-old man sustained an intra-articular GSW to a prior TKA. The patient was scheduled for irrigation and debridement with polyethylene liner exchange. Intraoperatively, the new polyethylene liner was unable to engage the tibial tray. Damage to the locking mechanism on the tibial tray was suspected so total revision proceeded. Upon inspection of the explanted components, it was noted that a bullet fragment offline from the missile trajectory had blocked the locking of the polyethylene liner in the tibial tray. Expeditious antibiotics should be given and meticulous debridement should be performed to avoid unnecessary total component revision.

Influence of thoracic radiology training on classification of interstitial lung diseases

INTRODUCTION

Interpretation of high-resolution CT images plays an important role in the diagnosis and management of interstitial lung diseases. However, interreader variation may exist due to varying levels of training and expertise. This study aims to evaluate interreader variation and the role of thoracic radiology training in classifying interstitial lung disease (ILD).

METHODS

This is a retrospective study where seven physicians (radiologists, thoracic radiologists, and a pulmonologist) classified the subtypes of ILD of 128 patients from a tertiary referral center, all selected from the Interstitial Lung Disease Registry which consists of patients from November 2014 to January 2021. Each patient was diagnosed with a subtype of interstitial lung disease by a consensus diagnosis from pathology, radiology, and pulmonology. Each reader was provided with only clinical history, only CT images, or both. Reader sensitivity and specificity and interreader agreements using Cohen's κ were calculated.

RESULTS

Interreader agreement based only on clinical history, only on radiologic information, or combination of both was most consistent amongst readers with thoracic radiology training, ranging from fair (Cohen's κ: 0.2-0.46), moderate to almost perfect (Cohen's κ: 0.55-0.92), and moderate to almost perfect (Cohen's κ: 0.53-0.91) respectively. Radiologists with any thoracic training showed both increased sensitivity and specificity for NSIP as compared to other radiologists and the pulmonologist when using only clinical history, only CT information, or combination of both (p < 0.05).

CONCLUSIONS

Readers with thoracic radiology training showed the least interreader variation and were more sensitive and specific at classifying certain subtypes of ILD.

SUMMARY SENTENCE

Thoracic radiology training may improve sensitivity and specificity in classifying ILD based on HRCT images and clinical history.

High Thoracic Tortuosity Is Associated With CT-Markers of Degeneration of the Descending Thoracic Aortic Wall

Objective/Introduction

Increased vascular tortuosity may be an independent marker of generalized aortic pathology. This study investigates the association between descending thoracic aortic tortuosity, aneurysm pathophysiology, and outcomes following EVAR in AAA patients.

Methods

Patients who underwent elective EVAR between 2004 and 2018 were reviewed. Thoracic tortuosity index (TTI) was measured using 3D reconstruction software. Patients were dichotomized across the median TTI into high tortuosity [HT] (TTI >1.27, Figure1(a) ) and low tortuosity [LT] (TTI ≤1.27, Figure 1(b) ) groups. Perioperative complications, postoperative outcomes, and CT-based features of thoracic aortic wall degeneration ( Figure 1(c)-(e) ) were collected and analyzed.

Results

136 patients underwent treatment: 70 HT patients, including 54 males and 16 females (mean age: 77 years), and 66 LT patients, including 62 males and 4 females (mean age: 70 years) (age; P < .001). LT patients exhibited greater prevalence of hypercholesterolemia and diabetes (P = .045, P = .01). Presence of degenerative aortic wall markers was greater in HT patients (P = .045). HT patients had higher incidence of multiple aneurysms concurrently present in their aorta compared to LT (32.8% vs 11.3%; P = .002). Frequency of AAA rupture/dissection was 4.3% for HT and 1.5% for LT (P = .339). A trend was observed in all cause 30-day mortality in the HT group (P = .061). Other perioperative complications and postoperative outcomes were similar between groups.

Conclusion

High TTI was associated with older age at time of EVAR, greater prevalence of degenerative markers in the descending thoracic aortic wall, and widespread aorto-iliac dilation. While not predictive of EVAR outcomes, TTI can provide valuable information regarding aneurysm pathophysiology.

Does body mass index influence long-term outcomes after anatomic total shoulder arthroplasty?

BACKGROUND

As of 2018, upwards of 42% of the US adult population was considered obese based on body mass index (BMI) scales. With the annual number of total joint replacements increasing, this study aimed to evaluate the impact BMI has on anatomic total shoulder arthroplasty (aTSA) outcomes.

METHODS

This was a retrospective analysis of 128 shoulders requiring primary aTSA. Patients were stratified into 3 cohorts based on their BMI at surgery: underweight/normal weight (U/NW; BMI ≤25.0), overweight (25.0 < BMI ≤ 30.0), and obese (BMI >30.0). BMI was separately analyzed as a continuous variable. Clinical endpoints were range of motion scores, including forward elevation, external rotation, and internal rotation, and patient-reported outcomes, including visual analog scale (VAS) scores, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) scores, and the Simple Shoulder Test (SST). Survivorship curves were calculated using Kaplan-Meier analysis.

RESULTS

Forty-four, 50, and 34 patient shoulders were in the U/NW, overweight, and obese cohorts, respectively. The mean follow-up time was 11.4 years. The U/NW cohort had more females (73%) compared with the overweight (34%; P = .0030) and obese (35%; P = .0015) groups; no differences were seen in revision rates. BMI was negatively correlated with age at surgery (r = -0.19, P = .014); it was not correlated with any of the 6 postoperative clinical endpoints. All 3 cohorts saw significant improvements in forward elevation, external rotation, internal rotation and VAS, ASES, and SST scores when compared preoperatively to postoperatively (P < .001). There were no significant differences between the 3 cohorts with respect to postoperative range of motion. Postoperative ASES scores were higher for the overweight cohort (82.6 ± 18.6) compared with both the U/NW (63.0 ± 25.1) and obese cohorts (70.5 ± 26.8) (P < .001). The overweight cohort also had higher SST (P = .0012) postoperative scores compared with the U/NW and obese cohorts; VAS scores were comparable between groups (P = .12). The nonobese (BMI <30) group (n = 94) showed 5-, 10-, and 15-year implant survival of 98.9%, 94.9%, and 83.9%, respectively compared to 97.1%, 93.7%, and 87.0% in the obese (BMI ≥30) group (n = 34). The log rank test revealed no significant difference in survival curves (P = .82).

CONCLUSION

To our knowledge, this is the longest follow-up study analyzing clinical endpoints stratified by BMI for aTSA. We saw that patients with a higher BMI required shoulder replacement at a significantly younger age. However, we also report that regardless of BMI, all patients saw significant improvements in patient-reported outcomes and range of motion scores postoperatively.

Identifying modifiable and nonmodifiable cost drivers of ambulatory rotator cuff repair: a machine learning analysis

INTRODUCTION

Implementing novel tools that identify contributors to the cost of orthopedic procedures can help hospitals maximize efficiency, minimize waste, improve surgical decision-making, and practice value-based care. The purpose of this study was to develop and internally validate a machine learning algorithm to identify key drivers of total charges after ambulatory arthroscopic rotator cuff repair and compare its performance with a state-of-the-art statistical learning model.

METHODS

A retrospective review of the New York State Ambulatory Surgery and Services Database was performed to identify patients who underwent elective outpatient rotator cuff repair (RCR) from 2015 to 2016. Initial models were constructed using patient characteristics (age, gender, insurance status, patient income, Elixhauser Comorbidity Index) as well as intraoperative variables (concomitant procedures and services, operative time). These were subsequently entered into 5 separate machine learning algorithms and a generalized additive model using natural splines. Global variable importance and partial dependence curves were constructed to identify the greatest contributors to cost.

RESULTS

A total of 33,976 patients undergoing ambulatory RCR were included. Median total charges after ambulatory RCR were $16,017 (interquartile range: $11,009-$22,510). The ensemble model outperformed the generalized additive model and demonstrated the best performance on internal validation (root mean squared error: $7112, 95% confidence interval: 7036-7188; logarithmic root mean squared error: 0.354, 95% confidence interval: 0.336-0.373, R²: 0.53), and identified major drivers of total charges after RCR as increasing operating room time, patient income level, number of anchors used, use of local infiltration anesthesia/peripheral nerve blocks, non-White race/ethnicity, and concurrent distal clavicle excision. The model was integrated into a web-based open-access application capable of providing individual predictions and explanations on a case-by-case basis.

CONCLUSION

This study developed an ensemble supervised machine learning algorithm that outperformed a sophisticated statistical learning model in predicting total charges after ambulatory RCR. Important contributors to total charges included operating room time, duration of care, number of anchors used, type of anesthesia, concomitant distal clavicle excision, community characteristics, and patient demographic factors. Generation of a patient-specific payment schedule based on the Agency for Healthcare Research and Quality risk of mortality highlighted the financial risk assumed by physicians in flat episodic reimbursement schedules given variable patient comorbidities and the importance of an accurate prediction algorithm to appropriately reward high-value care at low costs.

Efeito da COVID-19 na artroplastia de ombro em um centro médico terciário na cidade de Nova York

Objetivo A pandemia de COVID-19 causou uma pausa sem precedentes em cirurgias eletivas, inclusive artroplastia de ombro. Procuramos determinar as possíveis diferenças clínicas e/ou demográficas entre os pacientes que realizaram artroplastia de ombro durante a pandemia em comparação com o ano anterior (2019).

Métodos Os registros institucionais foram consultados para obtenção de informações sobre pacientes submetidos a artroplastia de ombro entre 1° de março a 1° de julho de 2019 e 2020. Dados demográficos, amplitude de movimento, duração da cirurgia, tempo de hospitalização, condições à alta e manejo pós-operatório foram analisados.

Resultados O tempo médio de cirurgia foi de 160 ± 50 minutos em 2020 e de 179 ± 54 minutos em 2019 (p = 0,13). O tempo médio de internação foi de 36 ± 13 horas em 2020 e de 51 ± 40 horas em 2019 (p = 0,04). Em 2019, 96% dos pacientes fizeram fisioterapia, enquanto 71% o fizeram em 2020 (p = 0,003). Todos os pacientes de 2019 e 86% dos pacientes de 2020 participaram do acompanhamento pós-operatório presencial (p = 0,006). Os pacientes de 2019 retornaram para a consulta médica em média 14 ± 11 dias após a cirurgia; os pacientes de 2020 retornaram para o acompanhamento em 25 ± 25 dias (p = 0,10). A amplitude de movimento, a idade, a pontuação da American Society of Anesthesiologists (ASA, na sigla em inglês) e as taxas de complicações não diferiram entre as coortes.

Conclusão Os pacientes submetidos a cirurgia na fase inicial da pandemia eram demográfica e clinicamente semelhantes aos pacientes de 2019. No entanto, o tempo de internação diminuiu de forma significativa durante a pandemia de COVID-19. O acompanhamento pós-operatório e a fisioterapia foram adiados em 2020, mas isso não levou a diferenças nas taxas de complicações ou de reinternações em comparação às da coorte de 2019.

Nível de Evidência III.

Hartmann's reversal: factors affecting complications and outcomes

AIM

Hartmann's procedure is commonly performed emergently for infectious, inflammatory, or malignant processes. Most patients historically do not undergo reversal, and those who do have been found to suffer significant morbidity. The aim of this study was to study factors associated with complications after Hartmann's reversal and to provide information and guidance to surgeons.

METHOD

A retrospective review of patients undergoing Hartmann's reversal between May 2002 and October 2017 was conducted at a tertiary medical center. Data included patient characteristics at the time of surgery and intra- and postoperative complications. Chi-square test was used for categorical variables. The Wilcoxon signed rank or t test where appropriate was used for multivariate analysis.

RESULTS

Two hundred forty-nine patients were included. Mean age at reversal was 58.8 years, and 114 (58%) were male. Sixty-two (31.8%) patients experienced a major complication following reversal. Eight (4%) patients had an anastomotic leak. Thirteen (6.67%) patients had an intra-abdominal abscess which required either IR or operative drainage. Patients who experienced a major complication were more likely to have an ASA 4 at time of reversal (14.3% vs. 4.24%, p = 0.019), liver disease (6.6% vs. 0.8%, p = 0.021), and BMI < 30 (35% vs. 17.3%, p = 0.020).

CONCLUSIONS

Nearly one-third of patients who had reversal surgery experienced a major complication. Four percent of patients undergoing reversal had an anastomotic leak, comparable to previously reported rates. Patients with ASA 4, liver disease, and BMI < 30 were at higher risk of a major complication following reversal. Patients who underwent laparoscopic reversal had no significant difference in outcomes.

AIM

What does this paper add to the literature? The decision of whether to reverse a colostomy after Hartmann's procedure. Our study aims to identify risk factors associated with complications after Hartmann's reversal to better guide surgeon's facing the dilemma of whether or not to reverse the stoma.

Comparison of Subacromial Injection and Interscalene Block for Immediate Pain Management After Arthroscopic Rotator Cuff Repair

PURPOSE

To compare the efficacy of a subacromial injection (SAI) with a single-shot interscalene block (ISB) for immediate postoperative pain relief after outpatient arthroscopic rotator cuff repair (ARCR).

METHODS

We performed a retrospective chart review of consecutive patients who underwent ARCR. Patients received either an ISB before the procedure or an SAI after the procedure. Preoperative baseline patient characteristics were collected and compared. Visual analog scale (VAS) pain scores were recorded preoperatively, at 15-minute intervals over a 120-minute period in the postanesthesia care unit (PACU), and at discharge. Differences in VAS scores between groups were compared with known values of the minimal clinically important difference, and the percentage of patients with VAS scores below the patient acceptable symptom state was tabulated. Differences between preoperative characteristics were assessed using the Mann-Whitney U, Fisher exact, or χ² test. The Mann-Whitney U test was also used to evaluate VAS scores and total time spent in the PACU between groups.

RESULTS

The median VAS score was significantly lower in the ISB group at PACU admission, at all intervals throughout the PACU stay, and at discharge (P < .0001). The median total time in the PACU was 107 minutes (25th percentile-75th percentile, 90-120 minutes) and 210 minutes (25th percentile-75th percentile, 175-274 minutes) in the ISB and SAI groups, respectively (P < .0001). Between-group differences in VAS scores were greater than the values of the minimal clinically important difference at each measured interval. A total of 98% and 67% of patients in the ISB and SAI groups, respectively, were discharged with VAS scores below the patient acceptable symptom state of 3.

CONCLUSIONS

Patients receiving an ISB experience significantly less pain than those receiving an SAI. In addition, they are discharged home from the PACU in half the time as patients receiving an SAI. On the basis of the comparative efficacy, an SAI cannot replace an ISB after ARCR. The ISB should therefore remain the standard of care as an adjunct to postoperative analgesia for patients who undergo outpatient ARCR.

LEVEL OF EVIDENCE

Level III, retrospective, comparative therapeutic trial.

Supplemental systemic oxygen support using an intestinal intraluminal membrane oxygenator

An intraluminal membrane oxygenator (IMO) prototype was surgically inserted in the ileum and evaluated as a method of supporting systemic oxygenation in an acutely hypoxemic porcine model. Animals were assigned randomly to the test (n = 12) or the control (n = 8) groups, which underwent identical protocols with the exception of the O2 flow in the IMO device, which was shut off in the control group. In each case, hypoxia was induced by a reduction in the inspired oxygen fraction (FiO2) to 0.14. A highly significant improvement (p < 0.005) in arterial and venous O2 content and lower arteriovenous O2 difference (p < 0.05), cardiac output, and hemoglobin (p < 0.005) were found in the test group during hypoxia. The results show that it is possible to meet a physiologically significant portion of the body's O2 demands via the intestine during respiratory hypoxia and suggests that similar devices may be of significant potential value as a supplemental oxygenation device in cases of respiratory distress.

Piezoelectricity in cementum, dentine and bone

Unlike the dental hard tissues, bone remodels when subjected to orthodontic forces. Bone is also piezoelectric (generates a surface electrical charge upon application of force). In dentine and cementum from sperm whale teeth (which gave samples of sufficient size), the existence and magnitude of piezoelectricity were examined and compared with human bone. Both dental tissues were found to be piezoelectric with coefficients of 0.027 and 0.028 pC/N, respectively; the coefficient of human bone was eight times greater (0.22 pC/N). Thus the strength of the piezoelectric effect was correlated with the known capacities of the tissues to undergo adaptive remodelling. This result is consistent with the theory that piezoelectricity mediates orthodontically induced alveolar remodelling.

Gout and pseudogout of the temporomandibular joint

The temporomandibular joint is rarely affected by gout or pseudogout. The following article presents two case reports that demonstrate gout and pseudogout of the temporomandibular joint. The surgical treatment and diagnostic criteria for these entities are presented and discussed.

Electrical stimulation of mandibular osteotomies in rabbits

The use of electrical stimulation to accelerate mandibular healing was studied in rabbits that had undergone bilateral mandibular slot osteotomies. Stimulation on the day of surgery and for 3 successive days thereafter (2 hours per day) produced accelerated healing as evaluated histologically 8 days after surgery. Stimulation during the entire postoperative period did not result in accelerated healing. Intermittent stimulation in the early postoperative period may be clinically useful for accelerating the healing of mandibular fractures.

Isolated fracture of the first rib associated with facial trauma

Isolated fractures of the first rib are rare and often, though not always, indicative of severe trauma. The causes of first rib fracture are various, as are the sometimes serious complications of such a fracture. Since the oral and maxillofacial surgeon is involved many times in the primary care of the trauma patient, he must consider the possibility of first rib fracture and be alerted to the possible sequelae.

Giant cell tumor of the mandible

A case of giant cell tumor of the mandible is presented, with treatment and follow-up for two and a half years. Although the lesion had characteristics of giant cell granuloma described by Jaffe, its aggressive clinical behavior influenced the diagnosis and treatment. Prosthetic rehabilitation was accomplished with a mandibular staple bone plate placed through a bone graft.

The dynamic Morris biphase appliance for stabilization of flail facial bones

This report presents our experience with a modification of the Morris biphase appliance. We have modified the device to let the patient open his or her mouth immediately after surgery to allow for intraoral suture line care. The device prevents deviation of the remaining mandible toward the operated side of the face. We believe this has lessened the esthetic, masticatory, and speech difficulties of the two patients in whom we used the device. We conclude the device deserves further testing.

Unicystic ameloblastoma

The unicystic ameloblastoma should be considered a distinct entity and treated conservatively. The following case report emphasizes the use of computerized axial tomography in the diagnosis of this lesion. The detailed histology and conservative surgical therapy is discussed.

Adynamic ileus as a complication of iliac bone removal: report of two cases

This report described two cases of postoperative adynamic ileus after iliac bone autografts. The etiology, treatment, and differentiation of this problem from mechanical obstruction are discussed.

Use of pocket inlay grafts and tuberoplasty in maxillary prosthetic construction

A method of surgical and prosthetic rehabilitation of the severely atrophic maxillae using pocket inlay grafts and tuberoplasty is presented. At 2 1/2 years postoperatively, the denture in a patient treated in this manner remains stable with good retention and function. The principles presented may be applied in a variety of situations to achieve greater retention and stability of the maxillary denture.

Use of intradiploic cranial screws with a biphase appliance as a modified headframe

An alternative method to using a standard headframe has been presented. A case has been presented demonstrating the application of the extracranial fixation using the biphase appliance. The basic acrylic headframe can be modified for traction wires as needed to produce maxillomandibular fixation.

Solitary subcutaneous lipoma: report of case

A submental lipoma in a 66-year-old black man is presented. The etiology of the lesion is discussed and related to our case. The solitary subcutaneous lipoma is treated by excision. Recurrence is rare, and sarcomatous degeneration seldom occurs. Most other lesions of similar presentation and location occur in a younger age group than that of our patient.

A histologic evaluation of bone response to bur cutting with and without water coolant

Thirty-six bony cuts were made in the lateral aspect of the mandibles of mongrel dogs. Irrigation was employed in eighteen cuts, while the remaining eighteen were cut without irrigation. Histologic specimens were obtained at 1 hour, 1 day, 3 days, 1 week, and 3 weeks. Early specimens showed marked clot retraction from the bony walls in the nonirrigated cuts, while irrigated cuts demonstrated more firmly adherent and better organized clots. In later specimens, bone formation was less mature in the defects made without irrigation. Inflammation and necrosis of bone were minimal or absent in all sections. Defects made without irrigation exhibited delayed healing in this study.

Bone-induction potential of mineralized collagen gel xenografts

Mineralized collagen gel xenografts may supply a mechanical and biochemical substrate for cell growth and hard tissue formation. This might be translated into a means of producing onlaid bone formation where clinically applicable.

Dentigerous cyst with mural ameloblastoma

A case of a 14-year-old black girl with a lesion that appeared to be a dentigerous cyst is presented. Radiographic appearance, findings of a bone scan and biopsy by aspiration are discussed. Histologic findings showed that the lesion was an ameloblastoma that is believed to have arisen from the dentigerous cyst wall.

Mucosal grafting over Proplast-augmented edentulous ridges: a pilot study

Full-thickness mucosal grafts were placed over Proplast-augmented alveolar ridges in six mongrel dogs. Five of the six grafts were successful, indicating that properly prepared recipient sites over Proplast provide adequate blood supply to support free grafts. A thicker keratinizing graft such as palatal mucosa may provide greater protection for the implant under the stress of a prosthesis.

The surgical sequence of combined total maxillary and mandibular osteotomies

In many instances, orthognathic surgical cases require multiple osteotomies in the maxilla and mandible to achieve the most desirable result. When the entire maxilla and mandible are freed from their relationship with the remaining craniofacial complex, accurate repositioning and adequate stabilization can present problems. These problems can be minimized by operating in the proper sequence or by staging the procedure. Staging should be considered for the more complicated cases; in any instance, the maxilla should be operated on first.

Cutaneous necrosis of the chin following mandibular advancement and genioplasty. (Case report)

A case of necrosis of the soft tissue over the chin following mandibular advancement and genioplasty is presented. The aetiology, pathology, and clinical management of pressure sores is discussed.

Cat scratch disease. Report of a case

Members of the health care professions who examine the head and neck regions should be familiar with cat scratch disease and consider it in a differential diagnosis. This article summarizes the history, literature, diagnosis, and treatment of cat scratch disease.

Ludwig's angina due to bacteroides

This case presentation concerns a 21-year-old Negro man in whom Ludwig's angina developed after a dental infection. The many serious complications encountered with such an infection are described in some detail. The involvement of anaerobic Bacteroides in infections of the head and neck is also noted and the approach to treatment is described.