United States

Background: Minimal clinically important differences (MCID) reflect significant changes in the health-
related quality of life after a clinical intervention. Although MCID is widely used in spine literature, few studies have been done to establish the radiographic and clinical predictors of achieving MCID in elderly
patients undergoing surgery for adult spinal deformity (ASD) correction. This study assesses preoperative and post-operative radiographic parameters, comorbidities and peri-operative complications as potential predictors of MCID in elderly patients ≥65yr with ASD. We hypothesized that patients who failed to meet MCID thresholds for ASD surgery are more likely to have significant
preoperative spinal imbalance and clinical co-morbidities.

Methods: Patients included were ≥65yr with ASD, had ≥5 levels fusion including the lumbosacral junction, and had complete preoperative, postoperative and 2yr Oswestry Disability Index (ODI), Visual Analog Scale (VAS), and radiographic measurements. Patients with 2yr postoperative improvement of ODI &gt;10 or VAS &gt;2.5 when compared with preoperative baseline were considered to meet MCID. A Student t test was used to assess the difference of variables across patients that achieved MCID and those that did not.

Results:104 patients ≥65yr surgically managed for ASD were separated into 2 cohorts: 67 patients that met MCID and 37 patients that did not. Patients that met MCID had significantly lower preoperative sagittal alignment (8.66 vs 11.88 cm, p=0.05) when compared with those without improvement. Other preoperative radiographic parameters such as coronal balance and T1-pelvic angle were not significantlydifferent. Post-operative radiographic parameters were all similar between the two groups. Patients meeting MCID had a lower rate of previous spinal surgery (22.3%) vs the non-improved group (51.4%) (p&lt;0.01). The MCID group also had a lower rate of pre-existing stroke (3%) compared with the non- improved group (13.5%) (p=0.04). Achieving MCID is also more likely in patients with scoliosis as
compared to kyphosis (84% vs 45% p=0.03).

Conclusion: Preoperative sagittal mal-alignment, a predominantly kyphotic deformity, revision surgery,
and a history of stroke are predictive of failure to meet MCID in deformity surgery for patients ≥65yr. Knowledge of these characteristics can be beneficial in counseling patients about prognosis after surgery and post-operative expectations.

AMA Research Challenge 2022

Predictors of Minimally Clinical Importance Difference in Elderly Patients (≥ 65 years of age) Undergoing Spinal Deformity Surgery

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Ricardo Correa, MD, EdD
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Stephanie Strohbeen, MD
 
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Jessica Li, MD/PhD Candidate
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Charles Lopresto, DO

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Registration Is Required

Welcome to the largest national, multi-specialty research event featuring research from 750 medical students, residents and fellows, and international medical graduates.


Background: Minimal clinically important differences (MCID) reflect significant changes in the health-
related quality of life after a clinical intervention. Although MCID is widely used in spine literature, few studies have been done to establish the radiographic and clinical predictors of achieving MCID in elderly
patients undergoing surgery for adult spinal deformity (ASD) correction. This study assesses preoperative and post-operative radiographic parameters, comorbidities and peri-operative complications as potential predictors of MCID in elderly patients ≥65yr with ASD. We hypothesized that patients who failed to meet MCID thresholds for ASD surgery are more likely to have significant
preoperative spinal imbalance and clinical co-morbidities.

Methods: Patients included were ≥65yr with ASD, had ≥5 levels fusion including the lumbosacral junction, and had complete preoperative, postoperative and 2yr Oswestry Disability Index (ODI), Visual Analog Scale (VAS), and radiographic measurements. Patients with 2yr postoperative improvement of ODI >10 or VAS >2.5 when compared with preoperative baseline were considered to meet MCID. A Student t test was used to assess the difference of variables across patients that achieved MCID and those that did not.

Results:104 patients ≥65yr surgically managed for ASD were separated into 2 cohorts: 67 patients that met MCID and 37 patients that did not. Patients that met MCID had significantly lower preoperative sagittal alignment (8.66 vs 11.88 cm, p=0.05) when compared with those without improvement. Other preoperative radiographic parameters such as coronal balance and T1-pelvic angle were not significantlydifferent. Post-operative radiographic parameters were all similar between the two groups. Patients meeting MCID had a lower rate of previous spinal surgery (22.3%) vs the non-improved group (51.4%) (p<0.01). The MCID group also had a lower rate of pre-existing stroke (3%) compared with the non- improved group (13.5%) (p=0.04). Achieving MCID is also more likely in patients with scoliosis as
compared to kyphosis (84% vs 45% p=0.03).

Conclusion: Preoperative sagittal mal-alignment, a predominantly kyphotic deformity, revision surgery,
and a history of stroke are predictive of failure to meet MCID in deformity surgery for patients ≥65yr. Knowledge of these characteristics can be beneficial in counseling patients about prognosis after surgery and post-operative expectations.

poster

Background. The peroneus longus (PL) and peroneus brevis (PB) tendons comprise the lateral compartment of the leg and work to stabilize the foot during weight-bearing. Peroneal tendinopathy can precipitate persistent lateral ankle pain and induce substantial functional disability. The process by which peroneal pathology can progress to significant lateral ankle dysfunction is thought to stem from asymptomatic, subclinical peroneal tendinopathy. As such, there is substantial clinical benefit to identifying asymptomatic patients with this condition before it progresses to disability. Various ultrasound (US) characteristics have been observed in peroneal tendinopathy. The purpose of this study is to identify the frequency of subclinical tendinopathic characteristics in asymptomatic peroneal tendons. 
Methods. A total of 170 participants underwent bilateral US examination of the foot and ankle. These images were assessed for abnormalities of the PL and PB tendons by a group of physicians, and frequencies of abnormalities were recorded. This team consisted of an orthopedic surgeon specializing in foot and ankle surgery, a fifth-year orthopedic surgery resident, and a family medicine physician with musculoskeletal sonographer certification.
Results. 340 PL and 340 PB tendons were assessed. Of these, 68 (20%) PL and 41 (12.1%) PB tendons had abnormal traits. Specifically, 24 PLs (7.1%) and 22 PBs (6.5%) had circumferential fluid, 16 PLs (4.7%) and 9 PBs (2.6%) had noncircumferential fluid, 27 PLs (7.9%) and 6 PBs (1.8%) had thickening, 36 PLs (10.6%) and 12 PBs (3.5%) had heterogenicity, 10 PLs (2.9%) and 2 PBs (0.6%) had hyperemia, and 1 PL (0.3%) had calcification. 
Conclusion. Of the 170 participants, 34% had at least one abnormal PL characteristic identified on US. Twenty-two percent of participants were found to have at least one abnormal PB trait. In the study population, heterogenicity was the most prevalent abnormality found in PL tendons, while circumferential fluid was the most common abnormal trait in PB tendons. Understanding the frequency of abnormalities in asymptomatic peroneal tendons may aid clinicians in identifying subclinical tendinopathy before it progresses to dysfunction.

Prevalence of Abnormal Ultrasound Findings in Asymptomatic Peroneal Tendons

Background: Scoliosis is a common spinal malformation, which is typically diagnosed and assessed for severity by measuring the Cobb angle on a plain radiograph. Although manual methods are still considered the gold standard, recent studies have shown that PACS (picture archiving and communication systems methods) have comparable intraobserver and interobserver reliability levels for experienced clinicians. However, there is limited data for these reliability measures in less experienced medical personnel, especially with digital methods like PACS.

Methods: 10 radiographic images of scoliosis patients were obtained via a retrospective chart review. After a brief training exercise, Cobb angle measurements were performed twice on each radiograph, separated by one week, using the PACS method. Subject groups ranged in their level of prior training and experience with Cobb angle measurements from inexperienced medical students, to more experienced resident physicians, and highly experienced orthopedic surgeons and radiologists. Data was compared for interrater reliability levels within groups and between groups, and for individual intra-rater reliability levels. Intra-class correlation coefficient (ICC) between averaged measured were calculated and a Cronbach’s α obtained. An α of ≥ 0.9 is considered excellent agreement, 0.9 > α ≥ 0.8 is good, 0.8 > α ≥ 0.7 is acceptable, 0.7 > α ≥ 0.6 is questionable and α < 0.6 is poor or unacceptable reliability. 

Results: Resident physicians, orthopedic surgeons, and radiologist subject groups had significant levels of between-group and within-group inter-rater reliability as well as individual intra-rater reliability levels (α ≥ 0.9, p<0.001). Inexperienced medical student raters had poor within-group interrater reliability (α = -0.176). One medical student had a significant level of individual intra-rater reliability (α > 0.9, p<0.001) while the other had poor intra-rater reliability (α < 0.6, p=0.035). Between-group inter-rater reliability for medical students and more experienced professionals was poor (α < 0.6).

Conclusions: While PACS has been shown to be a reliable method for measuring Cobb angle and an acceptable substitute for conventional manual techniques, it is not a reliable method in less experienced trainees such as medical students.

Reliability of Cobb angle measurement using PACS in less-experienced medical personnel

Abstract Title: 
Reverse Total Shoulder Arthroplasty: The Impact of Implant Design on Postoperative Internal Rotation

Background
Reverse total shoulder arthroplasty (rTSA) is a ubiquitous surgical procedure indicated for numerous glenohumeral pathologies. Repeated evidence demonstrates its efficacy in improving shoulder function and reducing pain; however, improvements in rotational motion have been inconsistent. Attention has recently shifted toward internal rotation (IR) as an important component of activities of daily living (ADL). Subsequently, IR has been strongly associated with post-operative patient satisfaction. To date, there has been little discussion regarding implant design on IR. As the community shifts toward more lateralized center-of-rotation and varus humeral implants, it is unclear how this will impact rotational motion.

Methods
A systematic review was performed following PRISMA guidelines. Search strategies were implemented in PubMed with the keywords (internal rotation) AND (reverse) AND (shoulder). Inclusion criteria included a minimum 12-month follow-up, reporting of IR, and implant description. Exclusion criteria included rTSA solely for proximal humerus fractures, oncologic reconstruction, or severe glenoid deformity, revision rTSA, and procedures including latissimus dorsi or tendon transfers. After review, 56 studies from 332 unique citations were selected.

Results
Analysis was performed on 56 studies consisting of 7788 shoulders treated with rTSA at a mean follow-up of 42.4 months. IR was reported for 7288 shoulders (94%). Measurement systems were highly heterogeneous necessitating conversion to a common metric. This permitted comparative analysis of 46 studies encompassing 6123 shoulders (79%).

Varus (135°) humeral implant neck shaft angles (NSA) were associated with the greatest post-operative IR, though intermediate (145-147°) and valgus (150-155°) NSA produced comparable results. Varus and intermediate NSA outperformed valgus NSA in terms of mean change in IR.

Accounting for humeral NSA, lateralized glenospheres resulted in greater post-operative IR. When classifying implant systems with the Werthel global offset system, highly lateralized and very highly lateralized systems produced greater post-operative IR than medialized systems.

Conclusion
The results of this systematic review indicate that lateralization of the center-of-rotation and varus humeral NSA optimize IR. A classic Grammont-style rTSA, a medialized center-of-rotation with a valgus NSA, was associated with predictably poor IR. This review suggests trends toward lateralized center of rotation and varus NSA will result in improved IR.


Reverse Total Shoulder Arthroplasty: The Impact of Implant Design on Postoperative Internal Rotation

Risk Factors and Characteristics of Recalcitrant Osteomyelitis Following Appropriate Surgical and Antibiotic Treatment

Introduction: The purpose of this study was to compare osteoarthritis (OA) diagnosis prevalence between isolated anterior cruciate ligament (ACL) reconstruction and ACL reconstruction with meniscus involvement (meniscus repair (MR), partial meniscectomy (APM), both isolated and combined). We hypothesized that meniscus injury in combination with ACL injury would have increased OA prevalence. 
Methods: The PearlDiver Mariner database was used in this study which contains insurance claims information on more than 91 million orthopaedic patients. Five cohorts were identified for this study using Current Procedural Terminology (CPT) codes and included those between the ages of 16 and 60 that underwent isolated ACL reconstruction, isolated MR, ACL+MR, isolated APM, or ACL+APM repair. Groups were matched by patient age, sex, and presence of diagnosis codes for obesity and morbid obesity with each group consisting of 10,125 patients (4685 females and 5440 males). OA prevalence and odds ratio were compared against isolated ACL reconstruction. 
Results: A significantly greater proportion of APM and ACL+APM patients were diagnosed with knee OA within five years of surgery when compared to isolated ACL patients (APM= 735/10,125 (7.3%) and ACL+APM= 459 (4.5%) vs ACL= 338 (3.3%), p=<0.0001 for both comparisons). The odds of knee OA were also greater in APM and ACL+APM patients when compared to isolated ACL patients (Odds Ratio: APM= 2.27 and ACL+APM= 1.38). Patients undergoing isolated MR also demonstrated a slight, yet still statistically significant, increase in OA prevalence and odds within five years of surgery (MR= 396 (3.9%), Odds Ratio= 1.18, p=0.03). Patients undergoing ACL+MR showed a decrease in prevalence of OA when compared to isolated ACL reconstruction (ACL+MR= 254 (2.5%), odds ratio= 0.75, p=0.0005).
Conclusions: Our results support the hypothesis that meniscus injury at arthroscopy significantly increases the risk of developing diagnosed OA within five years. APM, whether isolated or combined with ACL reconstruction, demonstrated the greatest incidence of OA within 5 years when compared to matched groups of patients that underwent ACL reconstruction and/or meniscus repair. These “big data” results confirm previous reports from prospective ACL cohorts, and further support efforts to repair the menisci whenever possible. Interestingly, the lowest incidence of subsequent OA diagnosis was in the group that underwent combined ACL reconstruction and meniscus repair. Future research is needed to better understand the biological and biomechanical mechanisms that contribute to the potentially protective effect of combined ACL reconstruction and meniscus repair.

Save the Meniscus! Incidence of Osteoarthritis Diagnosis Greatest Following Partial Meniscectomy, Either Isolated or in Combination with ACL Reconstruction

Introduction: Despite the prevalence of osteoarthritis in patients with multiple sclerosis (MS) being equivalent to that of the general population, very little research exists on outcomes and complications following shoulder arthroplasty in patients with this condition. The purpose of the current study was to utilize a national database to determine the effect of MS on implant related complications following anatomic and reverse shoulder arthroplasty procedures and evaluate for any differences in complications between the two prosthesis types. 

Methods: Patients with MS who underwent anatomic total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RSA) were identified in a national insurance database using the appropriate ICD-9 and ICD-10 diagnostic codes. Patients who underwent TSA, RSA, and RSA for fracture with a diagnosis of MS were identified and compared to non-MS cohorts in a 5:1 manner. Each cohort was then assessed for revision surgery, periprosthetic joint infection, and prosthetic dislocation and compared.

Results: Patients with MS undergoing RSA for fracture experienced increased rates of periprosthetic joint infection compared to those undergoing RSA for fracture without MS (OR 3.6, CI 1.47-8.91, p = 0.035). There were no other significant differences when comparing complications between patients with MS undergoing shoulder arthroplasty procedures compared to controls without the disorder, or any significant differences when comparing complications between patients with MS undergoing TSA and RSA (p > 0.05).

Conclusions: Patients undergoing RSA for fracture with MS appear to be at increased risk for postoperative periprosthetic joint infection compared to patients without MS, and should be counseled accordingly. However, MS does not appear to confer a statistically significant increased risk for the remainder of the studied complications following TSA, RSA, and RSA for fracture. The current study suggests that surgeons should not alter their treatment strategies or implant selection for patients undergoing shoulder arthroplasty based on a diagnosis of MS.

Shoulder Arthroplasty in Patients with Multiple Sclerosis - Complications Stratified by Arthroplasty Type

Obesity, defined as a body mass index (BMI) ≥ 30, is associated with musculoskeletal injuries. Past literature assumed low BMI was a risk factor for fractures, and high BMI was protective against fractures. However, present studies suggest that the relationship between obesity and the risk of fracture is site-specific. To our knowledge, no study has considered the impact of obesity on tibial plateau fracture, the proximal end of the tibia. Therefore, this study aims to investigate if obese patients are at higher risk of developing open proximal tibia fractures when compared with non-obese patients with a similar mechanism of injury.
A retrospective study was performed at a level one trauma hospital, and we identified patients with proximal tibia fracture from January 1, 2015, to December 31, 2019. We reviewed electronic records for demographic variables, fracture type (open or closed) and categorized patients into obese for BMI ≥30 kg/m2 or non-obese for BMI 18.5-24.9 kg/m2. We categorized the mechanism of injury into four injury patterns: assault, fall, motor vehicle accident (MVC), and motorcycle accident. For statistical analysis, we performed t-tests and p-value of 0.05 to be statistically significant.
Sixty patients with proximal tibia fractures were included, and seven percent sustained open proximal tibia fractures. The mean BMI was 32 kg/m2. Overall, 63% of the patients had an obese BMI, and 37% had a non-obese BMI. One hundred percent of patients with open proximal tibia fracture had BMI ≥30 kg/m2; however, the type of fracture (open vs. closed) was not statistically significant (p = 0.286) between the obese and non-obese groups. We also observed that all the patients with open proximal tibia fractures were involved in MVC. However, we observed no statistically significant relationship (p = 0.357) when we looked at the effect of being obese on the likelihood of having an open fracture for those whose mechanism of injury is MVC.

Research on obesity and lower extremity fractures has provided varying and complicating results. Our study demonstrated that obese individuals do not have an increased risk of developing open proximal tibia fractures than non-obese individuals following the same mechanism of injury.


The Association between Open Proximal Tibia Fractures and Obesity

The Association Between Preoperative Diabetes Status and Adverse Events Following Primary Anterior Cruciate Ligament Reconstruction

Introduction: 
Anatomic total shoulder arthroplasty (ATSA) has proven to be a successful treatment for glenohumeral osteoarthritis (GHOA). Nonetheless, it is uncertain if there is a correlation between pre-operative rotator cuff muscle atrophy on post clinical outcomes in patients who get an ATSA. The purpose of this study is to evaluate if there is a correlation between pre-operative rotator cuff muscle volume and clinical outcomes following ATSA for GHOA. 

Methods:
In this study, 198 shoulders underwent ATSA for GHOA with a minimum of 2 years follow up identified by a maintained prospective registry. Each rotator cuff muscle was assessed and measured on a standardized preoperative magnetic resonance image (MRI), using OsiriX image analysis, to generate an area of total muscle volume. The pre and postoperative patient reported clinical outcomes are the American Shoulder and Elbow standardized shoulder assessment (ASES), Single Assessment Numerical Evaluation (SANE), range of motion (ROM), and pain level. The above outcomes were assessed for correlations with preoperative rotator cuff muscle volume.

Results: 
A total of 198 patients with a mean age of 62.0 ± 7.3 years (range: 42-78), underwent ATSA for GHOA with a minimum follow up of 2 years. MRIs were evaluated for a quantitative measurement of muscle atrophy. A univariate analysis did not show any significant findings when evaluating for supraspinatus, teres minor, and infraspinatus muscle volume in relation to clinical outcomes. There was a negative correlation in subscapularis muscle volume and its impact on postoperative internal rotation (R= -.142, P = 0.046). Furthermore, the size ratio of the posterior cuff to subscapularis muscle volume demonstrated a significant negative correlation for change in SANE scores (R= -.141, P= 0.047), external rotation (R= -0.149, P= 0.036), and internal rotation (R= -0.190, P=0.007). Nonetheless, there were no correlations between size ratio and other clinical outcomes. 

Conclusion: 
Preoperative rotator cuff muscle volume does not have an obvious correlation on clinical outcomes. However, there is a negative association with the ratio of the posterior cuff to subscapularis, consistent with prior studies that have assessed volume in patients undergoing reverse total shoulder arthroplasty. 


The Effect of Rotator Cuff Integrity on Clinical Outcomes Following Anatomic Total Shoulder Arthroplasty

Abstract Title: 
The Single Assessment Numeric Evaluation (SANE), PROMIS-UE, & QuickDASH for Elective Hand Surgeries
Background:
Validated patient-reported outcome measures provide important insight into condition-specific clinical outcomes, but they place a considerable time burden on patients, clinicians, and other staff. In response, efforts have been made to validate single-question surveys, such as the Single Assessment Numeric Evaluation (SANE) score, across orthopedic conditions, but few prospective studies have evaluated the SANE questionnaire for hand conditions specifically. Therefore, the purpose of this study was to validate the use of the SANE score in patients undergoing routine elective hand surgeries. We hypothesized that SANE scores would positively correlate with two other validated upper extremity surveys, PROMIS-UE and Quick-DASH. 
Methods:
Patients scheduled to undergo carpal tunnel release and trigger finger release surgery completed three surveys (SANE, the Patient-Reported Outcomes Measurement Information System Upper Extremity (PROMIS-UE) item bank, and the shortened Disabilities of the Arm, Shoulder and Hand (QuickDASH) questionnaire) preoperatively and at two postoperative time points (2-4 weeks postop and >90 days postop). Based on an a priori power calculation and values from previous studies, a minimum sample of 82 patients was needed to achieve 80% power to detect a change after treatment or intervention of the minimal clinically important difference (MCID) or greater on the QuickDASH with a 2-sided level of significance of .025.
Results:
A total of 89 patients completed all three timepoints. There were strong positive correlations between the changes in QuickDASH scores and the changes in PROMIS-UE scores between all three timepoints, which we expected since these surveys served as our controls. There was also a strong positive correlation between the changes in the SANE scores and the changes in QuickDASH scores when comparing early post-op to late post-op (Pearson coefficient 0.529187631, p-value <0.0001). All other timepoint comparisons had a moderate positive correlation between SANE and the validated surveys. 
Conclusion:
One possible explanation as to why most of our correlations were moderate rather than strong is because of the difference in scaling. SANE’s 0%-100% scale allowed for a much larger percent change than the other two surveys’ (SANE's percent change range was 0-2900%, whereas QuickDASH's was 0-115.8% and PROMIS-UE's was 0-154.2%). Future studies are recommended to determine if changing the SANE scale to 1-10 would remedy this and lead to stronger correlations. With this in mind, our data still suggest that SANE can successfully evaluate elective hand surgery outcomes in the early and late postoperative periods.

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Prevalence of Abnormal Ultrasound Findings in Asymptomatic Peroneal Tendons

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