Ten-Year Trends in Level of Evidence in Hand Surgery

BACKGROUND

The purposes of this study were to analyze the trends in Oxford level of evidence (LOE), LOE of most-cited articles, and association between LOE and journal impact factor (IF) and SCImago Journal Rank (SJR) over a 10-year period (2009-2018) in 3 prominent hand surgery journals, specifically HAND, Journal of Hand Surgery (American Volume) (JHS), and Journal of Hand Surgery (European Volume) (JHSE).

METHODS

All articles published from 2009 to 2018 in HAND, JHS, and JHSE were reviewed for assigned or available LOE. Data were pooled and analyzed for trends in LOE; relationship among IF, SJR, and LOE; and citation density.

RESULTS

A total of 3921 total publications were tabulated from 2009 to 2018, with the majority of studies being level V (1700, 43%) and fewer studies being level I (146, 4%). Over the 10-year study period, there was no significant change in frequency of level I studies for any journal. HAND trended significantly toward higher LOE, JHS trended toward higher LOE, and JHSE trended toward decreased LOE without significance. Among all journals, the annual number of articles and the average LOE were independent significant predictors of IF and SJR. Statistically significant correlations were found between citation density and LOE for JHS and HAND.

CONCLUSIONS

Higher quality evidence is becoming more prevalent in the hand surgery literature over the past 10 years. Annual articles, average LOE, and level I and II and level IV articles were significant predictors of increasing IF and SJR.

Analysis of the Quality of Prospective Randomized Controlled Trials for Treatment of Boxer's Fractures

BACKGROUND

This study aimed to review level I and II therapeutic studies on boxer's fractures to measure variation in quality among the highest level study designs.

METHODS

We used quantitative measures of study quality to evaluate prospective randomized controlled trials (RCTs) of treatments of boxer's fractures. A search of PubMed, using terms "boxer's fracture" and "fifth metacarpal neck fracture" identified 164 articles from 1961 to 2019. From this list, we identified 6 RCTs. Two observers classified each trial according to 3 systems: the Oxford Levels of Evidence, the modified Coleman Methodology Score, and the revised Consolidated Standards of Reporting Trials (CONSORT) score.

RESULTS

The 2 reviewers were consistent in their use of the Oxford Levels of Evidence (100% agreement). The differences between the average modified Coleman Methodology scores and the average CONSORT scores assigned by the 2 observers were not significant (46.2 vs 45.3 points, κ = 0) and (13.7 vs 14.3 points, κ = 0.33), respectively. Both observers rated all the studies as level I and as unsatisfactory according to the Coleman Methodology Score (100% and 100%), and less than half as unsatisfactory according to the CONSORT score (50% and 17%). Areas of deficiency included randomization, blinding, group comparability, clinical effect measurements, and allocation into treatment arms.

CONCLUSION

Classifying orthopedic scientific reports according to the levels of evidence implies a degree of respect for level I and II studies that may not always be merited. Our data suggest that the quality of higher level studies, namely those involving boxer's fractures, varies and may often be unsatisfactory when critically evaluated.

Hand Surgeons Are Tackling Tougher Scaphoids: A Study of ABOS Candidate Data

BACKGROUND

This study will evaluate whether those who have completed a hand fellowship treat a disproportionate number of scaphoid fractures based on recent American Board of Orthopaedic Surgery (ABOS) data. We hypothesize that surgeons who have completed a fellowship in hand surgery will address most surgically treated scaphoid fractures, particularly those with fracture nonunions or requiring graft.

METHODS

We queried the ABOS database for case log information submitted for part II of the ABOS examination. This search included all cases with Current Procedural Terminology codes for procedures related to scaphoid fixation. Demographic information, case volume, type of case, and complication rate were compared for hand fellowship-trained surgeons and those who had completed other fellowships as well as non-fellowship-trained surgeons.

RESULTS

During the study period, 1686 surgeons reported treating 4244 scaphoid fractures. Of these surgeons, 1180 had completed a hand surgery fellowship. Hand fellowship-trained surgeons were shown to have operatively treated more scaphoid fractures both in total volume and on a per-surgeon basis. Hand fellowship-trained surgeons were also found to have performed a significantly higher proportion of difficult cases, which were those listed as being a malunion/nonunion or those incorporating a pedicle graft. There was no difference in the complication rate between the 2 groups.

CONCLUSION

Among those orthopedic surgeons reporting case information for part II of the ABOS certification examination, statistically significant differences exist in case volume and case difficulty among surgeons with different areas of fellowship training. Complication rates increase with patient age and examination year.

Treatment patterns of ABOS part II candidates: A decline of operative management among geriatric proximal humerus fractures over the decade (2010-2020)

BACKGROUND

The purpose of this study was to assess trends in ABOS part II candidate's operative management of geriatric (≥65 years) proximal humerus fractures over the 2010-2020 decade.

METHODS

This retrospective database cohort study utilized the American Board of Orthopaedic Surgery (ABOS) database for candidates taking Part II of their boards. Surgical coding was reviewed and the ICD10 data was correlated to the CPT code for shoulder arthroplasty or open reduction internal fixation. We investigated the number of proximal humerus fracture operative cases per year, the percent arthroplasty used per year, the stratification of percent arthroplasty per orthopaedic fellowship subspecialty and geographic region.

RESULTS

A total of 2,409 operative cases for proximal humerus fractures in patients 65 years of age and older were submitted by 1,420 ABOS candidates. There was a 37% reduction in operatively managed proximal humerus fractures among ABOS part II candidates between the first half of the decade (2010-2015, 263.2 +/- 13.4) and the second half of the decade (2016-2020, 166 +/- 31.2; p<.05). There also was a downward trend with a 53% reduction in percent treated with arthroplasty as compared to ORIF during those same windows (2010-2015, 34.4 +/-11.7) and (2016-2020, 16.2 +/- 6.4; p<.5). Partitioned by single fellowship training, Shoulder and Elbow (S&E) surgeons performed the highest percent arthroplasty at 25.2%, followed by Sports at 23.1% and the lowest percent arthroplasty was Trauma at 11.7%. The Southeast United States had the lowest percentage arthroplasty at 15.8% as compared to the Midwest (23.8%) and Northeast (25.8%).

CONCLUSION

Despite the rapid growth of both the elderly population and related geriatric proximal humerus fractures, ABOS candidates are treating less with surgery. There has been approximately a 37% decrease in the total number of operatively treated proximal humerus fractures between the first and second half 2010-2020 decade. When operative treatment is performed, there is a trend towards ORIF over an arthroplasty. Trauma fellowship trained surgeons are less likely to perform an arthroplasty as compared to other subspecialties. The Southeast region is least likely to perform an arthroplasty as compared to the Midwest or Northeast.

Treatment trends in distal humerus fractures between ABOS part II candidates

PURPOSE

The purpose of this study was to determine how fellowship training influences the treatment of distal humerus fractures with either total elbow arthroplasty (TEA) or open reduction internal fixation (ORIF).

METHODS

The American Board of Orthopaedic Surgery (ABOS) Part II Examination Database was queried for all orthopaedic surgeons who sat for the Part II examination between the years 2003-2019. Inclusion criteria were ORIF or TEA cases, selected by individual CPT codes for each procedure, and patients of at least age 65 years who sustained acute distal humerus fractures. Analysis was performed for each type of fellowship training completed, total number of procedures performed, the type of procedure performed, patient demographics, and any complications.

RESULTS

There were 149 TEAs and 1306 ORIFs performed for distal humerus fractures between the exam years of 2003-2019. The proportion of TEA to ORIF increased from 7.6% to 11.0%. Partitioned by fellowship training, Hand and Upper Extremity surgeons performed 69 (17.4%) TEAs and 328 (82.6%) ORIFs, Shoulder and Elbow surgeons performed 34 (29.6%) TEAs and 81 (70.4%) ORIFs, Sports Medicine surgeons performed 14 (5.1%) TEAs and 263 (94.6%) ORIFs, and Trauma surgeons performed 16 (4.2%) TEAs and 366 (95.8%) ORIFs. Hand and Upper Extremity surgeons treated the most distal humerus fractures (397, 27.3%), followed by Trauma surgeons (382, 26.3%).

CONCLUSION

Our data suggests that fellowship training does influence the surgical decision-making process for treating distal humerus fractures in elderly populations. Hand and Upper Extremity surgeons performed the greatest number of TEA for acute distal humerus fractures, followed by Shoulder and Elbow surgeons. Conversely, trauma surgeons performed the lowest proportion of TEA to ORIF.

LEVEL OF EVIDENCE

III.

The Epidemiology of Hand and Finger Lacerations in United States Emergency Departments

BACKGROUND

Hand and finger lacerations presenting to U.S. emergency departments (EDs) are common, although the burden of these injuries is not well understood.

OBJECTIVE

Our aim is to describe the epidemiology and causes of hand and finger lacerations in U.S. EDs.

METHODS

This National Electronic Injury Surveillance System database review investigates hand and finger lacerations presenting to EDs in the United States from 2015 to 2019.

RESULTS

Annually, hand and finger lacerations account for 243,844 and 587,451 ED visits, respectively. Affected patients are frequently White (70.5%), male (63.4%), and aged 18 through 44 years (46.3%). The top three products linked to hand and finger lacerations are knives (30.5%), metal containers (4.2%), and drinkware (3.8%), and men are less likely to have injuries from these products than women, especially knives (odds ratio 0.76; 95% confidence interval 0.60-0.96; p < 0.02). Although a minority of hand and finger lacerations involve alcohol (1.2%), men have greater rates of alcohol involvement than women (χ²₁ = 11.7; p < 0.001). Lacerations frequently occur in the home (61.3%). Many patients (44.2%) present to very large hospitals, and nearly one-half of patients younger than 5 years and one-third of patients aged 5 through 17 years present to pediatric hospitals. Most patients (97.4%) are treated and released without admission and 0.2% are transferred to another hospital. Patients with alcohol, drug, or medication involvement are more likely to leave against medical advice, be admitted, or held for observation (p < 0.001).

CONCLUSIONS

Hand and finger lacerations result in a significant number of ED visits. A better understanding of injury trends and presentations can guide injury prevention in manufacturing, education, and public health.

A High-Sensitivity International Knee Documentation Committee Survey Index From the PROMIS System: The Next-Generation Patient-Reported Outcome for a Knee Injury Population

BACKGROUND

Patient-reported outcomes (PROs) measure progression and quality of care. While legacy PROs such as the International Knee Documentation Committee (IKDC) survey are well-validated, a lengthy PRO creates a time burden on patients, decreasing adherence. In recent years, PROs such as the Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function and Pain Interference surveys were developed as computer adaptive tests, reducing time to completion. Previous studies have examined correlation between legacy PROs and PROMIS; however, no studies have developed effective prediction models utilizing PROMIS to create an IKDC index. While the IKDC is the standard knee PRO, computer adaptive PROs offer numerous practical advantages.

PURPOSE

To develop a nonlinear predictive model utilizing PROMIS Physical Function and Pain Interference to estimate IKDC survey scores and examine algorithm sensitivity and validity.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 3.

METHODS

The MOTION (Military Orthopaedics Tracking Injuries and Outcomes Network) database is a prospectively collected repository of PROs and intraoperative variables. Patients undergoing knee surgery completed the IKDC and PROMIS surveys at varying time points. Nonlinear multivariable predictive models using Gaussian and beta distributions were created to establish an IKDC index score, which was then validated using leave-one-out techniques and minimal clinically important difference analysis.

RESULTS

A total of 1011 patients completed the IKDC and PROMIS Physical Function and Pain Interference, providing 1618 complete observations. The algorithms for the Gaussian and beta distribution were validated to predict the IKDC (Pearson = 0.84-0.86; R² = 0.71-0.74; root mean square error = 9.3-10.0).

CONCLUSION

The publicly available predictive models can approximate the IKDC score. The results can be used to compare PROMIS Physical Function and Pain Interference against historical IKDC scores by creating an IKDC index score. Serial use of the IKDC index allows for a lower minimal clinically important difference than the conventional IKDC. PROMIS can be substituted to reduce patient burden, increase completion rates, and produce orthopaedic-specific survey analogs.

C-terminal domain small phosphatase 1 (CTDSP1) regulates growth factor expression and axonal regeneration in peripheral nerve tissue

Peripheral Nerve Injury (PNI) represents a major clinical and economic burden. Despite the ability of peripheral neurons to regenerate their axons after an injury, patients are often left with motor and/or sensory disability and may develop chronic pain. Successful regeneration and target organ reinnervation require comprehensive transcriptional changes in both injured neurons and support cells located at the site of injury. The expression of most of the genes required for axon growth and guidance and for synapsis formation is repressed by a single master transcriptional regulator, the Repressor Element 1 Silencing Transcription factor (REST). Sustained increase of REST levels after injury inhibits axon regeneration and leads to chronic pain. As targeting of transcription factors is challenging, we tested whether modulation of REST activity could be achieved through knockdown of carboxy-terminal domain small phosphatase 1 (CTDSP1), the enzyme that stabilizes REST by preventing its targeting to the proteasome. To test whether knockdown of CTDSP1 promotes neurotrophic factor expression in both support cells located at the site of injury and in peripheral neurons, we transfected mesenchymal progenitor cells (MPCs), a type of support cells that are present at high concentrations at the site of injury, and dorsal root ganglion (DRG) neurons with REST or CTDSP1 specific siRNA. We quantified neurotrophic factor expression by RT-qPCR and Western blot, and brain-derived neurotrophic factor (BDNF) release in the cell culture medium by ELISA, and we measured neurite outgrowth of DRG neurons in culture. Our results show that CTDSP1 knockdown promotes neurotrophic factor expression in both DRG neurons and the support cells MPCs, and promotes DRG neuron regeneration. Therapeutics targeting CTDSP1 activity may, therefore, represent a novel epigenetic strategy to promote peripheral nerve regeneration after PNI by promoting the regenerative program repressed by injury-induced increased levels of REST in both neurons and support cells.

Dorsal Bridge Plate for Distal Radius Fractures: A Systematic Review

PURPOSE

This study presents patient demographics, injury characteristics, outcomes, and complications associated with dorsal bridge plating (DBP) in the treatment of distal radius fractures.

METHODS

A literature search performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines identified 206 articles, 12 of which met inclusion criteria, accounting for 310 patients. Included articles contained the results of DBP for treatment of distal radius fractures with reported outcomes between 1988 and 2018. Data were pooled and analyzed focusing on patient demographics, as well as 3 primary outcomes of complications, range of motion (ROM), and Disabilities of the Arm, Shoulder, and Hand (DASH) and QuickDASH scores.

RESULTS

Average age was 55 years, median follow-up was 24 months, and the most common use was in comminuted (92%) intra-articular (92%) distal radius fracture caused by fall (58%), or motor vehicle collision or motorcycle collision (27%). A minority of patients had open fractures (16%) and most were cases of polytrauma (65%). Median time from placement to DBP removal was 17 weeks (mean, 119 days). At final follow-up, mean wrist ROM was 45° flexion, 50° extension, 75° pronation, and 73° supination. Mean DASH score was 26.1, and mean QuickDASH score was 19.8. The overall rate for any complication was 13%; the most common was hardware failure (3%) followed by symptomatic malunion or nonunion (3%), and persistent pain after hardware removal (2%).

CONCLUSIONS

Dorsal bridge plating was found to be used most commonly in intra-articular, comminuted distal radius fractures with overall functional wrist ROM, moderate patient-reported disability, and a 13% complication rate at follow-up.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Epidemiology and Long-Term Outcomes of Wrist Sprains in Military Academy Cadets

BACKGROUND

The American Society for Surgery of the Hand advises patients that symptoms after wrist sprains resolve in 6 weeks and that recovery is usually excellent; however, there is scant supporting evidence for this reassurance.

PURPOSE

To describe the epidemiology and report long-term outcomes of wrist sprains.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

The US Department of Defense Military Health System Management Analysis and Reporting Tool was queried for wrist sprain International Classification of Diseases, Ninth Revision, codes between 2005 and 2008 among US Military Academy cadets. The electronic medical records were reviewed to obtain demographic information, mechanism of injury, and patient characteristics. A telephone survey was conducted to collect Single Assessment Numeric Evaluation (SANE) score, the shortened version of Disabilities of the Arm, Shoulder and Hand (QuickDASH) score, and ability to return to full military duty.

RESULTS

Of the 90 patients identified, 49 patients (50 wrists) met the final inclusion criteria. The mean patient age was 21 years, the majority were male (86%), and most sprains occurred during athletics (65%) and military activities (20%). Most patients (61%) had radiographs taken after index wrist sprain, and few (14%) underwent magnetic resonance imaging (MRI). After a mean follow-up of 10.4 years, most patients (78%) had no further wrist injury. The average SANE and QuickDASH scores were 88 and 7.5, respectively. Two patients (4%) ultimately were treated with surgical repair. Most patients (96%) were on an upper extremity profile, limiting military duty for a median of 14 days. All patients ultimately returned to full military duty.

CONCLUSION

Patients with a wrist sprain diagnosis were followed for an average of 10 years. Although the majority (96%) of patients required a median of 14 days with limited upper extremity function, MRI is rarely indicated in the acute setting and most patients will never have another wrist injury and can expect excellent wrist recovery outcomes.

Bone Morphogenetic Protein in Scaphoid Nonunion: A Systematic Review

Background  Scaphoid nonunion can lead to carpal collapse and osteoarthritis, a painfully debilitating problem. Bone morphogenetic protein (BMP) has been successfully implemented to augment bone healing in other circumstances, but its use in scaphoid nonunion has yielded conflicting results. Case Description  The purpose of this study is to assess the outcomes and complications of scaphoid nonunion treated surgically with BMP. Literature Review  A literature review of all available journal articles citing the use of BMP in scaphoid nonunion surgery from 2002 to 2019 was conducted. We included studies that used BMP as an adjunct to surgical treatment for scaphoid nonunions in both the primary and revision settings with computed tomography determination of union. Demographic information, dose of BMP, tobacco use, outcomes, and complications were recorded. A total of 21 cases were included from four different studies meeting inclusion criteria. Clinical Relevance  The union rates were 90.5% overall, 100% for primary surgeries, and 77.8% for revision surgeries. Five patients (24%) experienced 11 complications, including four cases (19%) of heterotrophic ossification. Use of BMP in scaphoid nonunion surgery resulted in a 90.5% overall union rate but was also associated with complications such as heterotopic ossification. All included studies used BMP to augment bone graft, screw or wire fixation, or a combination of methods. The efficacy of BMP in scaphoid nonunion is unclear, and a sufficiently powered, randomized controlled trial is needed to determine optimal fixation methods, dosing, and morbidity of the use of BMP. Level of Evidence  This is a Level IC, therapeutic interventional study.

Nerve Reconstruction Using Processed Nerve Allograft in the U.S. Military

BACKGROUND

Processed nerve allograft (PNA) is an alternative to autograft for the reconstruction of peripheral nerves. We hypothesize that peripheral nerve repair with PNA in a military population will have a low rate of meaningful recovery (M ≥ 3) because of the frequency of blasting mechanisms and large zones of injury.

METHODS

A retrospective review of the military Registry of Avance Nerve Graft Evaluating Utilization and Outcomes for the Reconstruction of Peripheral Nerve Discontinuities database was conducted at the Walter Reed Peripheral Nerve Consortium. All adult active duty military patients who underwent any peripheral nerve repair with PNA for complete nerve injuries augmented with PNA visit were included. Motor strength and sensory function were reported as a consensus from the multidisciplinary Peripheral Nerve Consortium. Motor and sensory testing was conducted in accordance with the British Medical Research Council.

RESULTS

A total of 23 service members with 25 nerve injuries (3 sensory and 22 mixed motor/sensory) underwent reconstruction with PNA. The average age was 30 years and the majority were male (96%). The most common injury was to the sciatic nerve (28%) from a complex mechanism (gunshot, blast, compression, and avulsion). The average defect was 77 mm. Twenty-four percent of patients achieved a meaningful motor recovery. Longer follow-up was correlated with improved postoperative motor function (r = 0.49 and P = .03).

CONCLUSIONS

The military population had complex injuries with large nerve gaps. Despite the low rate of meaningful recovery (27.3%), large gaps in motor and mixed motor/sensory nerves are difficult to treat, and further research is needed to determine if autograft would achieve superior results.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic, Level III.

Managing Complex Peripheral Nerve Injuries Within the Military Health System: A Multidisciplinary Approach to Treatment, Education, and Research at Walter Reed National Military Medical Center

INTRODUCTION

Peripheral nerve injuries are a leading cause of disability within the Military Health System (MHS) patient population. Many peripheral nerve injuries (PNIs) are amenable to therapeutic intervention but require a timely diagnosis and prompt referral to a specialty center capable of intervention, as functional outcomes are directly related to the duration between injury and intervention. Even when appropriately identified, PNI management in the MHS is often challenged by the lack of an established pathway for care coordination and a limited awareness of available diagnostic and therapeutic resources. To address these potential shortcomings, the Walter Reed National Military Medical Center Peripheral Nerve Program (WRNMMC PNP) in Bethesda, MD, has been established to provide comprehensive, multidisciplinary care to peripheral nerve-injured patients across the MHS. Additionally, the WRNMMC PNP provides graduate medical education training in PNI management for multiple residency and fellowship programs, and it facilitates critical peripheral nerve research to advance knowledge within the field.

MATERIALS AND METHODS

A retrospective review of all patients evaluated by the WRNMMC PNP between December 2015 and April 2019 was conducted in order to identify pertinent patient demographic information, referral patterns, and PNI etiology data.

RESULTS

The WRNMMC PNP evaluated 356 patients consisting of active duty, dependents, retirees, and Veterans Affairs patients during the designated study period. These patients were referred by providers from more than nine different specialties from 78 commands across eight countries. The majority of these patients (222 patients) were referred for traumatic PNI. The WRNMMC PNP has also evaluated and treated patients with PNIs stemming from congenital and compressive etiologies. One hundred and one patients referred during this period were treated with surgery, while the remainder were managed through nonoperative means.

CONCLUSIONS

The WRNMMC PNP facilitates comprehensive, patient-centered care for PNI patients within the MHS. Moreover, the program helps to prepare the next generation of providers for evaluating and treating PNI patients through its involvement with graduate medical education training. It also conducts critical peripheral nerve research and lays the foundation for collaborations with other institutions involved with peripheral nerve research. In the years ahead, the WRNMMC PNP aims to expand its outreach and capabilities within the MHS through more expansive use of telemedicine consultation and the establishment of satellite peripheral nerve clinic sites.

Incidence of Scaphoid Fractures and Associated Injuries at US Trauma Centers

Backgound  The scaphoid is the most commonly fractured carpal bone and often presents as a diagnostic challenge. Fractures can often go unnoticed on initial radiographic evaluation and clinical presentation can vary significantly among patients. Awareness of high-risk cohorts assists practitioners in making the appropriate clinical diagnosis of acute scaphoid fracture. Materials and Methods  The National Trauma Data Bank is the world's largest trauma data repository. Utilizing the 2016 public use file, we isolated scaphoid fractures by anatomic fracture location by utilizing International Classification of Diseases, 10th revision coding. Reported cases of distal pole (S62.01), waist (S62.02), and proximal pole (S62.03) were included. This data was then queried to determine trends in mechanism of injury, demographic information, and associated injuries. Results  There were a total of 968,665 patients with 2,769 cases of reported scaphoid fractures resulting in 286 scaphoid fractures per 100,000 person-years. Males were more likely to sustain a scaphoid fracture than females. The most commonly encountered associated injuries were distal radius fractures, distal ulnar fractures, and nonscaphoid carpal bone fractures, respectively. Conclusions  Scaphoid fractures presenting to trauma centers are more commonly reported among males and those involved in motor vehicle accidents or falls. Appropriate scaphoid-specific radiographic imaging should be obtained as well as wrist and elbow images to evaluate for concomitant injuries, especially distal radius fractures.

Multifocal Calcific Periarthritis with Distinctive Clinical and Radiological Features in Patients with CD73 Deficiency

OBJECTIVE

Arterial calcification due to deficiency of CD73 (ACDC) is a hereditary autosomal recessive ectopic mineralization syndrome caused by loss-of-function mutations in the 5'-nucleotidase Ecto (NT5E) gene. Periarticular calcification has been reported but the clinical characterization of arthritis as well as the microstructure and chemical composition of periarticular calcifications and synovial fluid crystals has not been systematically investigated.

METHODS

Eight ACDC patients underwent extensive rheumatological and radiological evaluation over a period of 11 years. Periarticular and synovial biopsies were obtained from four patients. Characterization of crystal composition was evaluated by compensated polarized light microscopy, Alizarin red staining for synovial fluid along with x-ray diffraction and x-ray micro tomosynthesis for periarticular calcification.

RESULTS

Arthritis in ACDC patients has a clinical presentation of mixed erosive-degenerative joint changes with a median onset of articular symptoms at 17 years of age and progresses over time to the development of fixed deformities and functional limitations of small peripheral joints with eventually, larger joint and distinct axial involvement later in life. We have identified calcium pyrophosphate (CPP) and calcium hydroxyapatite (CHA) crystals in synovial fluid specimens and determined that CHA crystals are the principal component of periarticular calcifications.

CONCLUSION

This is the largest study in ACDC patients to describe erosive peripheral arthropathy and axial enthesopathic calcifications over a period of 11 years and the first to identify the composition of periarticular calcifications and synovial fluid crystals. ACDC should be considered among the genetic causes of early-onset osteoarthritis, as musculoskeletal disease signs may often precede vascular symptoms.

Generating the American Shoulder and Elbow Surgeons Score Using Multivariable Predictive Models and Computer Adaptive Testing to Reduce Survey Burden

BACKGROUND

The preferred patient-reported outcome measure for the assessment of shoulder conditions continues to evolve. Previous studies correlating the Patient-Reported Outcomes Measurement Information System (PROMIS) computer adaptive tests (CATs) to the American Shoulder and Elbow Surgeons (ASES) score have focused on a singular domain (pain or physical function) but have not evaluated the combined domains of pain and physical function that compose the ASES score. Additionally, previous studies have not provided a multivariable prediction tool to convert PROMIS scores to more familiar legacy scores.

PURPOSE

To establish a valid predictive model of ASES scores using a nonlinear combination of PROMIS domains for physical function and pain.

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 3.

METHODS

The Military Orthopaedics Tracking Injuries and Outcomes Network (MOTION) database is a prospectively collected repository of patient-reported outcomes and intraoperative variables. Patients in MOTION research who underwent shoulder surgery and completed the ASES, PROMIS Physical Function, and PROMIS Pain Interference at varying time points were included in the present analysis. Nonlinear multivariable predictive models were created to establish an ASES index score and then validated using "leave 1 out" techniques and minimal clinically important difference /substantial clinical benefit (MCID/SCB) analysis.

RESULTS

A total of 909 patients completed the ASES, PROMIS Physical Function, and PROMIS Pain Interference at presurgery, 6 weeks, 6 months, and 1 year after surgery, providing 1502 complete observations. The PROMIS CAT predictive model was strongly validated to predict the ASES (Pearson coefficient = 0.76-0.78; R² = 0.57-0.62; root mean square error = 13.3-14.1). The MCID/SCB for the ASES was 21.7, and the best ASES index MCID/SCB was 19.4, suggesting that the derived ASES index is effective and can reliably re-create ASES scores.

CONCLUSION

The PROMIS CAT predictive models are able to approximate the ASES score within 13 to 14 points, which is 7 points more accurate than the ASES MCID/SCB derived from the sample. Our ASES index algorithm, which is freely available online (https://osf.io/ctmnd/), has a lower MCID/SCB than the ASES itself. This algorithm can be used to decrease patient survey burden by 11 questions and provide a reliable ASES analog to clinicians.

Supercharge End-to-Side Nerve Transfer: Systematic Review

Background: To decrease the time to reinnervation of the intrinsic motor end plates after high ulnar nerve injuries, a supercharged end-to-side (SETS) anterior interosseous to ulnar motor nerve transfer has been proposed. The purpose of this study was to compile and review the indications, outcomes, and complications of SETS anterior interosseous to ulnar motor nerve transfer. Methods: A literature search was performed, identifying 73 papers; 4 of which met inclusion and exclusion criteria, including 78 patients. Papers included were those that contained the results of SETS between the years 2000 and 2018. Data were pooled and analyzed focusing on the primary outcomes: intrinsic muscle recovery and complications. Results: Four studies with 78 patients met inclusion and exclusion criteria. Most patients (33.3%) underwent SETS for an ulnar nerve lesion in continuity, the average age was 46.5 years, and the average follow-up was 10 months. The average duration of symptoms before surgery was 99 weeks, all patients had weakness and numbness, nearly all (96%) had atrophy, and half (53%) had pain. Grip and key pinch strength improved 202% and 179%, respectively, from the preoperative assessment. The vast majority (91.9%) recovered intrinsic function at an average of 3.7 months. Other than 8% of patients who did not recover intrinsic strength, no other complications were reported in any of the 78 patients. Conclusions: The SETS is a successful procedure with low morbidity, which may restore intrinsic function in patients with proximal nerve injuries.

The Burden of Fingertip Trauma on the US Military

Fingertip injuries in the military are common and often hinder the fighting force and support personnel. Injuries range from small subungual hematomas to proximal finger amputations. Treatment modalities are dictated by injury patterns, anatomic considerations, and the need to return to duty. Nail bed injuries should be repaired when possible and exposed bone or tendon is treated with appropriate soft tissue coverage. If soft tissue coverage is unobtainable, revision amputation should be performed with attention given to maintaining as much finger length as possible. Antibiotics may not be required, however they are often utilized in the deployed setting.

There Is No Role for Damage Control Orthopedics Within the Golden Hour

INTRODUCTION

Trauma systems within the United States have adapted the "golden hour" principle to guide prehospital planning with the goal to deliver the injured to the trauma facility in under 60 minutes. In an effort to reduce preventable prehospital death, in 2009, Secretary of Defense Robert M. Gates mandated that prehospital transport of injured combat casualties must be less than 60 minutes. The U.S. Military has implemented a 60-minute timeline for the transport of battlefield causalities to medical teams to include Forward Surgical Teams and Forward Resuscitative Surgical Teams. The inclusion of orthopedic surgeons on Forward Surgical Teams has been extrapolated from the concept of damage control orthopedics (DCO). However, it is not clear if orthopedic surgeons have yielded a demonstrable benefit in morbidity or mortality reduction. The purpose of this article is to investigate the function of orthopedic surgeons during the military "golden hour."

MATERIALS AND METHODS

The English literature was reviewed for evidence supporting the use of orthopedic surgeons within the golden hour. Literature was reviewed in light of the 2009 golden hour mandate by Secretary Gates as well as those papers which highlighted the utility of DCO within the golden hour.

RESULTS

Evidence for orthopedic surgery within the "golden hour" or in the current conflicts when the United States enjoys air superiority was not identified.

CONCLUSIONS

Within the military context, DCO, specifically pertaining to fracture fixation, should not be considered an element of golden hour planning and thus orthopedic surgeons are best utilized at more centralized Role 3 facility locations. The focus within the first hour after injury on the battlefield should be maintained on rapid and effective prehospital care combined with timely evacuation, as these are the most critical factors to reducing mortality.

Characterization of traumatized muscle-derived multipotent progenitor cells from low-energy trauma

Background

Multipotent progenitor cells have been harvested from different human tissues, including the bone marrow, adipose tissue, and umbilical cord blood. Previously, we identified a population of mesenchymal progenitor cells (MPCs) isolated from the traumatized muscle of patients undergoing reconstructive surgery following a war-related blast injury. These cells demonstrated the ability to differentiate into multiple mesenchymal lineages. While distal radius fractures from a civilian setting have a much lower injury mechanism (low-energy trauma), we hypothesized that debrided traumatized muscle near the fracture site would contain multipotent progenitor cells with the ability to differentiate and regenerate the injured tissue.

Methods

The traumatized muscle was debrided from the pronator quadratus in patients undergoing open reduction and internal fixation for a distal radius fracture at the Walter Reed National Military Medical Center. Using a previously described protocol for the isolation of MPCs from war-related extremity injuries, cells were harvested from the low-energy traumatized muscle samples and expanded in culture. Isolated cells were characterized by flow cytometry and q-RT-PCRs and induced to adipogenic, osteogenic, and chondrogenic differentiation. Downstream analyses consisted of lineage-specific staining and q-RT-PCR.

Results

Cells isolated from low-energy traumatized muscle samples were CD73+, CD90+, and CD105+ that are the characteristic of adult human mesenchymal stem cells. These cells expressed high levels of the stem cell markers OCT4 and NANOG 1-day after isolation, which was dramatically reduced over-time in monolayer culture. Following induction, lineage-specific markers were demonstrated by each specific staining and confirmed by gene expression analysis, demonstrating the ability of these cells to differentiate into adipogenic, osteogenic, and chondrogenic lineages.

Conclusions

Adult multipotent progenitor cells are an essential component for the success of regenerative medicine efforts. While MPCs have been isolated and characterized from severely traumatized muscle from high-energy injuries, here, we report that cells with similar characteristics and multipotential capacity have been isolated from the tissue that was exposed to low-energy, community trauma.

Flexor Tendon Repair with Adjunctive Botulinum Toxin Administration: A Systematic Review

Chemical denervation with Botulinum toxin has been proposed as an augment therapy to flexor tendon repairs to decrease complications including adhesions and re-rupture. We compiled and analyzed the results and complications for chemical denervation with Botulinum toxin in augmentation of flexor tendon repairs. Reviewed studies were from 1990-2018 and contained a minimum 3-month follow-up. A total of 26 patients were included in this review. All patients were reported to have excellent or good outcomes by the Strickland or Kleinert criteria. Complications were present in 9.3% of fingers including one with a flexion contracture, one with postoperative swelling, one with bowstringing, one with residual hypesthesia and first web contracture. Only one patient required re-operation. There were no cases of re-rupture or adhesions reported. All complications were unrelated to the use of Botulinum toxin. We conclude that Botulinum toxin therapy is a safe and efficacious augmentation to flexor tendon repair. (Journal of Surgical Orthopaedic Advances 30(1):036-039, 2021).

SARS-CoV-2 and limb ischemia: A systematic review

BACKGROUND

Recent spread of severe acute respiratory coronavirus syndrome-2 (SARS-CoV-2) has led to the coronavirus disease (COVID-19) pandemic, resulting in new challenges across all medical specialties. Limb and digit ischemia have been associated with COVID-19 infection. This systematic review includes primary studies of COVID-19 limb ischemia to identify risk factors, comorbidities, case characteristics, and treatment strategies to better understand the nature of this disease and its effects on the extremities.

METHODS

A literature search for studies detailing COVID-19 infected patients with limb or digit ischemia was performed, identifying 157 articles, 12 of which met inclusion criteria, accounting for 47 patients. Inclusion criteria were (1) primary studies, (2) positive disease diagnosis (3) limb ischemia, (4) reported treatment. Demographic data, case characteristics, treatments, outcomes and mortality were collected and pooled.

RESULTS

The average patient age was 67.6 years, predominantly male (79.6%). Of the 44 cases discussing treatment, 13 (30%) patients underwent medical treatment alone, while 23 (52.3%) patients underwent medical plus surgical treatment. Four patients (9.1%) were treated with observation. In 10 of the 12 studies, lab findings, thrombosis, or conclusions supporting a hypercoagulable state as a cause of limb/digit ischemia were cited. Five patients (10.6%) were on vasopressors and 8 patients (17.0%) were on a ventilator. Of those treated with observation alone, there was 100% resolution of symptoms. Of those treated medically without surgical intervention (17 patients), 6 patients (35.3%) were reported to have revascularization, 6 patients (35.3%) died, and the remaining outcomes were not reported. Medical and surgical treatment resulted in one limb amputation (4.4%) and altogether 74% of patients achieved revascularization of the affected limb/digit. Mortality rate was 45%.

CONCLUSIONS

COVID-19 infection may be associated with increased risk of limb or digital ischemia, although the quality of evidence supporting this theory is limited. Evidence of inflammatory-mediated thrombosis and endothelial injury are possible explanations which would support the use of immunotherapy in addition to anticoagulation for treatment or prevention of thromboembolic events. Current outcomes and treatment strategies are variable.

LEVEL OF EVIDENCE

IV.

Wartime Military Orthopaedics

Military orthopaedic surgeons are faced with hardship and decreased morale. Surgeons have frequent deployments and practice inefficiencies resulting in poor retention rates. The purpose of this analysis is to report demographics and factors effecting military retention. A survey was sent to all members of the Society of Military Orthopedic Surgeons. The survey obtained demographic information, as well as factors affecting retention and termination of service. Data was compared between subset groups within the total respondent population. Of active-duty personnel, 38.5% plan on staying in the military until retirement. Most surgeons entered into the military due to a desire to serve their country, while most people leave service due to higher pay as a civilian. A minority of military orthopaedic surgeons achieve military retirement; however, increased pay, increased control over practice, and decreased frequency of deployments are factors that could improve retention rates. (Journal of Surgical Orthopaedic Advances 30(2):116-119, 2021).

A microRNA Signature for Impaired Wound-Healing and Ectopic Bone Formation in Humans

BACKGROUND

Heterotopic ossification (HO) is characterized by the abnormal growth of ectopic bone in soft tissues, frequently occurring within the military population because of extensive orthopaedic combat trauma. MicroRNAs (miRNAs) are small noncoding RNAs that act as post-transcriptional regulators of gene expression. We hypothesized that a clinically relevant miRNA signature could be detected in patients following injury that progressed to form HO (HO+) or did not form HO (HO-).

METHODS

Tissue samples were obtained from injured servicemembers during their initial surgical debridements, and miRNA profiling was performed using a real-time miRNA polymerase chain reaction (PCR) array. Primary mesenchymal progenitor cells (MPCs) were harvested from debrided traumatized human muscle tissue, and cells were isolated and cultured in vitro. Mimic miRNAs were transfected into MPCs, followed by downstream in vitro analyses.

RESULTS

The investigation of the miRNA expression profile in the tissue of HO+ compared with HO- patients demonstrated a molecular signature that included the upregulation of miR-1, miR-133a, miR-133b, miR-206, miR-26a, and miR-125b. Transfection of each of these mature miRNAs into MPCs followed by osteogenic induction demonstrated that miR-1, miR-133a, miR-133b, and miR-206 enhanced osteogenic differentiation compared with control treatments. In silico and in vitro analyses identified the transcription factor SOX9 as a candidate downstream target of miR-1 and miR-206 miRNAs.

CONCLUSIONS

Our data demonstrated a molecular signature of miRNAs in the soft tissue of wounded servicemembers that was associated with the development of HO, providing novel insights into the underlying molecular mechanisms associated with posttraumatic HO.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Morphology and chemical identity of periarticular and vascular calcification in a patient with the rare genetic disease of arterial calcification due to deficiency of CD73 (ACDC)

A 54-year old female patient with the genetic disease of arterial calcification due to deficiency of CD73 was studied under the Undiagnosed Disease Program of the National Institutes of Health. She presented with symptoms of claudication in her 40s and later developed arthritic symptoms, ectopic calcification in her left hand and severe arterial calcifications of the lower extremities. Since little was known about the composition of the calcifications in arterial calcification due to deficiency of CD73, we investigated their chemical identity and microscopic morphology in this patient with imaging and x-ray diffraction analysis. We found that, microscopically, the bulk calcifications consisted of fragments of either solid or porous internal structure. Both periarticular and arterial calcifications were primarily hydroxyapatite crystals of the same crystalline anisotropy, but different crystalline grain sizes. This was consistent with the presence of hydroxyapatite crystals along with birefringent calcium pyrophosphate dihydrate crystals in the synovial fluid of the patients by polarized light microscopy. The result suggests that tissue calcification in both locations follow a similar biochemical mechanism caused by an increase in extracellular tissue-nonspecific alkaline phosphatase activity.

Factors Considered When Ranking Military Orthopedic Surgery Residency Candidates

INTRODUCTION

The intangible personal characteristic grit has become a popular topic of concentration within contemporary psychology studies. Grit is defined as persistent work on a focused topic for an extended period of time until a desired goal is achieved. Its application to physician selection and development is not well known. We sought to determine which factors were considered most important among leadership within the U.S. Army's orthopedic surgical training programs when selecting applications and ascertain if grit was one of the primary factors.

MATERIALS AND METHODS

A standardized, 18-question survey was sent to all program chairs, program directors, and assistant program directors at the six U.S. Army orthopedic surgery residency programs. Questions included demographic factors pertaining to both the individual and their respective training program. Participants were asked to rank, in order, the 10 most important variables when considering applicants. Each variable was ranked using a point system (1-10 with 10 as the best score), referred to as the factor score (FS). Further statistical analyses using descriptive statistics, paired t-test, and ANOVA were performed and reported.

RESULTS

The response rate was 83% (15/18). The most important variable considered was the applicant's performance on their audition rotation (FS = 9.8), which was significantly more important than any other variable (P = 0.001). The second most important variable was the applicant's USMLE scores (FS = 7.13), followed by involvement in research (FS = 5.60) and conscientiousness (FS = 4.73), respectively. Grit was considered the fifth most important variable (FS = 4.27). There was no significant difference in the ranking of grit among the different programs (P = 0.282). In applicants with low United States Medical Licensing Examination scores according to leadership idiosyncrasy, their audition rotation was considered a redeeming portion of their application (P = 0.02) followed by their level of grit.

CONCLUSIONS

The most important factor when considering an orthopedic surgery applicant was how well the applicant performed on an audition rotation, followed by their United States Medical Licensing Examination scores. Grit has become an important consideration in resident selection.

Surgical Repair of Acute TFCC Injury

Triangular fibrocartilage complex tears are a common source of ulnar-sided wrist pain and distal radioulnar joint instability. Symptoms recalcitrant to conservative management or injuries in high-demand athletes may indicate surgical management. Both open and arthroscopic techniques offer improvements in objective measures, patient-centered outcome scores, and return to work, but may be complicated by nerve irritation, persistent wrist instability, and pain. Recently developed knotless arthroscopic techniques are not well studied but may limit morbidity.

Acute Complications in Total Wrist Arthroplasty: A National Surgical Quality Improvement Program Review

Background  The study sought to assess the patient-based variables, surgical risk factors, and postoperative conditions associated with readmission after total wrist arthroplasty (TWA). Materials and Methods  All patients undergoing TWA were identified from the National Surgical Quality Improvement Program dataset from 2005 to 2016. Patient demographics, medical comorbidities, surgical characteristics, and outcomes were examined to isolate predictors for readmission within 30 days postoperatively. Results  A total of 57 patients were identified to have undergone TWA. The average patients were 62.3 (13.8) years old, female (57.7%), and most were treated in the outpatient setting (67.3%). Comorbid conditions included smoking (17.3%), diabetes (15.4%), and chronic steroid therapy (15.4%). No complications were identified in the 30-day postoperative period. There was a trend for increasing utilization of TWA over the years included. Conclusion  TWA is a safe procedure with low complication rates in the acute postoperative period. Increasing utilization is likely a result of improved outcomes and cost-effectiveness of TWA. Level of Evidence  This is a Level II, prognostic study.

Capitolunate Arthrodesis: A Systematic Review

PURPOSE

To compile and review the indications, outcomes, and complications of capitolunate arthrodesis (CLA).

METHODS

We performed a literature search identifying 33 articles, 6 of which met inclusion criteria, including 80 patients. Included publications contained the results of CLA with minimum 12-month follow-up between 2000 and 2018. Data were pooled and analyzed focusing on the primary outcomes of union and complications.

RESULTS

Average age of patients was 48 years (range, 22-86 years), median follow-up was 34 months (range, 12-198 months), and most common indication was scaphoid nonunion advanced collapse (59%). Nearly half underwent a concomitant triquetrum excision (49%). Most patients were pain-free (78%) and returned to work (92%). Grip strength and visual analog pain scale both improved after CLA. Whereas 96% fused within a reported 42 to 210 days (median, 70 days), 11% of patients had complications including nonunion (3.8%) and loose hardware (6.3%). The reoperation rate was 14%, including wrist arthrodeses and wrist arthroplasty.

CONCLUSIONS

Capitolunate arthrodesis is a feasible option for scapholunate advanced collapse and scaphoid nonunion advanced collapse wrists with complications similar to those encountered in 4-corner arthrodesis.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Global Excision of Severe Heterotopic Ossification of the Shoulder: A Case Report

CASE

A 21-year-old man sustained a closed glenohumeral fracture/dislocation as a pedestrian struck by a motor vehicle. He was treated nonoperatively and developed severe post-traumatic heterotopic ossification (HO) with near-complete shoulder ankylosis. We present our technique for safe surgical excision.

CONCLUSIONS

Excision led to improvements in motion and quality of life at 1 year postoperatively. Recommendations for successful HO excision around the shoulder include excision after at least 180 days, appropriate preoperative imaging to include cross-sectional imaging and a 3D model, intraoperative fluoroscopy, well-serviced instruments, preparation for iatrogenic fracture and/or neurovascular injury, meticulous hemostasis, postoperative HO prophylaxis, immediate postoperative therapy, and involvement of a multidisciplinary team.

Outcomes and Return to Work Following Complex Nerve Lacerations in the Volar Forearm in an Underserved Spanish-Speaking Population

Purpose

Lacerations to the ulnar and median nerve in the volar forearm have demonstrated considerable long-term clinical and socioeconomic impacts on patients. The purpose of this study was to evaluate the outcomes of complex volar forearm lacerations involving one or more major peripheral nerves in an economically disadvantaged patient population.

Methods

In this study, a retrospective analysis of 61 patients who sustained lacerations to the median nerve, ulnar nerve, or both with volar wrist lacerations was performed. Each patient’s preinjury and postinjury occupation, dominant extremity, and demographic variables were evaluated. Sensation recovery, motor recovery, Disabilities of the Arm, Shoulder, and Hand scores, visual analog scale scores, cold intolerance, and return to work were evaluated at 3, 6, and 12 months after the injury.

Results

Patients with isolated median nerve injuries demonstrated improved motor recovery compared with patients with isolated ulnar nerve injuries. Patients with combined nerve injuries had worse sensation recovery and motor recovery, and lower rates of return to work than either group of patients with isolated nerve injuries. Manual laborers had worse motor recovery and lower rates of return to work than did patients who were office workers.

Conclusions

Patients with combined median and ulnar nerve injuries have worse functional recovery and lower rates of return to work than do patients with isolated median or isolated ulnar nerve injuries at 1 year. Manual laborers demonstrated worse functional recovery and lower rates of return to work compared with office workers at 1 year.

Type of study/level of evidence

Therapeutic III.

Peripheral nerve repair throughout the body with processed nerve allografts: Results from a large multicenter study

BACKGROUND

Peripheral nerve damage resulting in pain, loss of sensation, or motor function may necessitate a reconstruction with a bridging material. The RANGER® Registry was designed to evaluate outcomes following nerve repair with processed nerve allograft (Avance® Nerve Graft; Axogen; Alachua, FL). Here we report on the results from the largest peripheral nerve registry to-date.

METHODS

This multicenter IRB-approved registry study collected data from patients repaired with processed nerve allograft (PNA). Sites followed their own standard of care for patient treatment and follow-up. Data were assessed for meaningful recovery, defined as ≥S3/M3 to remain consistent with previously published results, and comparisons were made to reference literature.

RESULTS

The study included 385 subjects and 624 nerve repairs. Overall, 82% meaningful recovery (MR) was achieved across sensory, mixed, and motor nerve repairs up to gaps of 70 mm. No related adverse events were reported. There were no significant differences in MR across the nerve type, age, time-to-repair, and smoking status subgroups in the upper extremity (p > .05). Significant differences were noted by the mechanism of injury subgroups between complex injures (74%) as compared to lacerations (85%) or neuroma resections (94%) (p = .03) and by gap length between the <15 mm and 50-70 mm gap subgroups, 91 and 69% MR, respectively (p = .01). Results were comparable to historical literature for nerve autograft and exceed that of conduit.

CONCLUSIONS

These findings provide clinical evidence to support the continued use of PNA up to 70 mm in sensory, mixed and motor nerve repair throughout the body and across a broad patient population.

In vivo model of human post-traumatic heterotopic ossification demonstrates early fibroproliferative signature

Background

The relationship between the tissue injury healing response and development of heterotopic ossification (HO) is poorly understood. Here we compare a rat blast model and human traumatized muscle from a blast injury to study the early signatures of osteogenesis and fibrosis during the formation of HO.

Methods

Rat and human tissues were characterized using histology, scanning electron microscopy, immunohistochemistry, as well as gene and protein expression analysis. Additionally, animals and humans were assessed radiographically for HO formation following injury.

Results

Markers of bone formation were dramatically increased in tissue samples from both humans and rats, and both displayed increased fibroproliferative regions within the injured tissues and elevated expression of markers of tissue fibrosis such as TGF-β1, Fibronectin, SMAD3 and PAI-1. Markers of inflammation and fibrosis (ACTA, TNFα, BMP1 and BMP3) were elevated at the RNA level in both rat and human samples. By day 42, bone formation in the rat blast model appeared similar in radiographs compared to human patients who progressed to develop post-traumatic HO.

Conclusions

Our data demonstrates that a similar early fibrotic response is evident in both the rat blast model and the human tissues following a traumatic injury and demonstrates the relevance of this animal model for future translational studies.

Dispelling the Myth of Work-Related de Quervain's Tenosynovitis

De Quervain's Tenosynovitis (DQT) is a common condition characterized by pain about the dorsal-radial aspect of the wrist, just proximal to the radial styloid. The condition is precipitated by a thickened first dorsal compartment and its tendons. The impression that DQT is caused from work-related injury is misdirected, as no study has established an association between hand usage at work or trauma with DQT. Physicians should exercise caution when discussing the causes and natural history of DQT with symptomatic patients.

Gender Disparities Within US Army Orthopedic Surgery: A Preliminary Report

INTRODUCTION

Women account for approximately 15% of the active duty US Army, and studies show that women may be at an increased risk of musculoskeletal injury during sport and military training. Nationally, the field of orthopedic surgery comprises 14% women, lagging behind other surgical fields. Demographics for US Military orthopedic surgeons are not readily available. Similarly, demographic data of graduating medical students entering Military Medicine are not reported. We hypothesize that a gender disparity within military orthopedics will be apparent. We will compare the demographic profile of providers to our patients and hypothesize that the two groups are dissimilar. Secondarily, we examine the demographics of military medical students potentially entering orthopedics from the Uniformed Services University of the Health Sciences (USUHS) or the Health Professions Scholarship Program.

METHODS

A census was formed of all US Army active duty orthopedic surgeons to include staff surgeons and residents, as well as US Army medical student graduates and orthopedic patients.

RESULTS

There are 252 Army orthopedic surgeons and trainees; 26 (10.3%) are women and 226 (89.7%) are men. There were no significant demographic differences between residents and staff. Between 2014 and 2017, the 672 members of the USUHS graduating classes included 246 Army graduates. Of those, 62 (25%) were female. Army Health Professions Scholarship Program graduated 1,072 medical students, with women comprising 300 (28%) of the group. No statistical trends were seen over the 4 yr at USUHS or in Health Professions Scholarship Program. In total, 2,993 orthopedic clinic visits during the study period were by Army service members, 23.6% were women.

CONCLUSION

There exists a gender disparity among US Army orthopedic surgeons, similar to that seen in civilian orthopedics. Gender equity is also lacking among medical students who feed into Army graduate medical education programs. The gender profile of our patient population is not reflected by that of providers. Because patients prefer providers of the same gender, this is a limitation to patient satisfaction and access to care for musculoskeletal injuries. Further study is underway to identify perceptions and potential causes of these disparities, including the critical perspective of our patients. In addition to the inherent benefits offered by diversity (e.g., expanding the talent pool and more perspectives for decision-making), ultimately it affords a greater ability to maintain a fit and ready force.

Outcome measures after medial ulnar collateral ligament reconstructions in a military population

BACKGROUND

Medial ulnar collateral ligament (MUCL) reconstruction outcomes are well described in competitive throwers but not in nonthrowers. This investigation elucidated epidemiologic variables, functional outcomes, and prognostic factors after MUCL reconstruction in young active patients.

METHODS

United States military service members undergoing MUCL reconstruction were isolated using the Management Analysis and Reporting Tool (M2) database from 2009 to 2016. Demographics, injury characteristics, and surgical variables were extracted. Multivariate analysis was performed, discerning variables predictive of postoperative functional outcomes, complications, and reoperation.

RESULTS

Sixty-six patients met inclusion criteria, and 47% participated in throwing sports. Of these, 36.4% reported a throwing mechanism of injury (MOI), 60.6% reported an acute trauma MOI, 59% reported preoperative ulnar nerve symptoms, and 39.4% experienced symptoms postoperatively. At final follow-up, average Disabilities of the Arm, Shoulder and Hand (DASH) and Mayo Elbow Performance Score (MEPS) scores were 10.8 ± 16.2 and 87.6 ± 17.1, respectively. A total of 86.4% reported no disability (DASH < 30), and 83.3% experienced good or excellent outcomes (MEPS >74). Age < 30 years, dominant arm injury, competitive throwing history, and throwing MOI correlated with improved DASH and MEPS scores, push-up count, postoperative pain and instability, and rates of ulnar nerve symptoms (P < .05). Psychiatric diagnosis and preoperative stiffness and instability were associated with lower outcome scores (P < .05). Ulnar nerve interventions did not correlate with presence or absence of postoperative ulnar nerve symptoms.

CONCLUSIONS

MUCL reconstruction demonstrates a high good-to-excellent outcome rate and low complication and revision rates in young active individuals with intense upper extremity demands. Nonthrowing MOIs and psychiatric pathology are associated with postoperative complications and poorer outcomes.

The Differentiation Stage of Transplanted Stem Cells Modulates Nerve Regeneration

In regenerative medicine applications, the differentiation stage of implanted stem cells must be optimized to control cell fate and enhance therapeutic efficacy. We investigated the therapeutic potential of human induced pluripotent stem cell (iPSC)-derived cells at two differentiation stages on peripheral nerve regeneration. Neural crest stem cells (NCSCs) and Schwann cells (NCSC-SCs) derived from iPSCs were used to construct a tissue-engineered nerve conduit that was applied to bridge injured nerves in a rat sciatic nerve transection model. Upon nerve conduit implantation, the NCSC group showed significantly higher electrophysiological recovery at 1 month as well as better gastrocnemius muscle recovery at 5 months than the acellular group, but the NCSC-SC group didn’t. Both transplanted NCSCs and NCSC-SCs interacted with newly-growing host axons, while NCSCs showed better survival rate and distribution. The transplanted NCSCs mainly differentiated into Schwann cells with no teratoma formation, and they secreted higher concentrations of brain-derived neurotrophic factor and nerve growth factor than NCSC-SCs. In conclusion, transplantation of iPSC-NCSCs accelerated functional nerve recovery with the involvement of stem cell differentiation and paracrine signaling. This study unravels the in vivo performance of stem cells during tissue regeneration, and provides a rationale of using appropriate stem cells for regenerative medicine.

Virtual stress testing of fracture stability in soldiers with severely comminuted tibial fractures

Virtual stress testing (VST) provides a non-invasive estimate of the strength of a healing bone through a biomechanical analysis of a patient's computed tomography (CT) scan. We asked whether VST could improve management of patients who had a tibia fracture treated with external fixation. In a retrospective case-control study of 65 soldier-patients who had tibia fractures treated with an external fixator, we performed VST utilizing CT scans acquired prior to fixator removal. The strength of the healing bone and the amount of tissue damage after application of an overload were computed for various virtual loading cases. Logistic regression identified computed outcomes with the strongest association to clinical events related to nonunion within 2 months after fixator removal. Clinical events (n = 9) were associated with a low tibial strength for compression loading (p < 0.05, AUC = 0.74) or a low proportion of failed cortical bone tissue for torsional loading (p < 0.005, AUC = 0.84). Using post-hoc thresholds of a compressive strength of four times body-weight and a proportional of failed cortical bone tissue of 5%, the test identified all nine patients who failed clinically (100% sensitivity; 40.9% positive predictive value) and over three fourths of those (43 of 56) who progressed to successful healing (76.8% specificity; 100% negative predictive value). In this study, VST identified all patients who progressed to full, uneventful union after fixator removal; thus, we conclude that this new test has the potential to provide a quantitative, objective means of identifying tibia-fracture patients who can safely resume weight bearing. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:805-811, 2017.

Quality of healing: defining, quantifying, and enhancing skeletal muscle healing

Skeletal muscle injury is common in everyday physical activity and athletics, as well as in orthopedic trauma and disease. The overall functional disability resulting from muscle injury is directly related to the intrinsic healing properties of muscle and extrinsic treatment options designed to maximize repair and/or regeneration of muscle tissue all while minimizing pathologic healing pathways. It is important to understand the injury and repair pathways in order to improve the speed and quality of recovery. Recent military conflicts in Iraq and Afghanistan have highlighted the importance of successfully addressing muscular injury and showed the need for novel treatment options that will maximize functional regeneration of the damaged tissue. These severe, wartime injuries, when juxtaposed to peacetime, sports-related injuries, provide us with interesting case examples of the two extreme forms of muscular damage. Comparing and contrasting the differences in these healing pathways will likely provide helpful cues that will help physicians recapitulate the near complete repair and regeneration in less traumatic injuries in addition to more severe cases.

Characterization of discrete subpopulations of progenitor cells in traumatic human extremity wounds

Here we show that distinct subpopulations of cells exist within traumatic human extremity wounds, each having the ability to differentiate into multiple cells types in vitro. A crude cell suspension derived from traumatized muscle was positively sorted for CD29, CD31, CD34, CD56 or CD91. The cell suspension was also simultaneously negatively sorted for either CD45 or CD117 to exclude hematopoietic stem cells. These subpopulations varied in terms their total numbers and their abilities to grow, migrate, differentiate and secrete cytokines. While all five subpopulations demonstrated equal abilities to undergo osteogenesis, they were distinct in their ability to undergo adipogenesis and vascular endotheliogenesis. The most abundant subpopulations were CD29+ and CD34+, which overlapped significantly. The CD29+ and CD34+ cells had the greatest proliferative and migratory capacity while the CD56+ subpopulation produced the highest amounts of TGFß1 and TGFß2. When cultured under endothelial differentiation conditions the CD29+ and CD34+ cells expressed VE-cadherin, Tie2 and CD31, all markers of endothelial cells. These data indicate that while there are multiple cell types within traumatized muscle that have osteogenic differentiation capacity and may contribute to bone formation in post-traumatic heterotopic ossification (HO), the major contributory cell types are CD29+ and CD34+, which demonstrate endothelial progenitor cell characteristics.

Human mesenchymal stem cells generate a distinct pericellular zone of MMP activities via binding of MMPs and secretion of high levels of TIMPs

Mesenchymal stem cells (MSCs) are attractive candidates for inclusion in cell-based therapies by virtue of their abilities to home to wound sites. However, in-depth characterization of the specific effects of MSCs on their microenvironments is needed to realize their full therapeutic potentials. Furthermore, since MSCs of varying properties can be isolated from a diverse spectrum of tissues, a strategic and rational approach in MSC sourcing for a particular application has yet to be achieved. For example, MSCs that activate their proteolytic environments may promote tissue remodeling, while those from different tissue sources may inhibit proteases and promote tissue stabilization. This study attempts to address these issues by analyzing MSCs isolated from three adult tissue sources in terms of their effects on their proteolytic microenvironments. Human bone marrow, adipose, and traumatized muscle derived MSCs were compared in their soluble and cellular-associated MMP components and activity. For all types of MSCs, MMP activity associated with the cell surface, but activity levels and MMP profiles differed with tissue source. All MSC types bound exogenous active MMPs at their surfaces. MSCs were also able to activate exogenous proMMP-2 and proMMP-13. This is in marked contrast to the MSC soluble compartment, which strongly inhibited MMPs via endogenous TIMPs. The exact TIMP used to inhibit the exogenous MMP differed with MSC type. Thus, MSCs saturate their environment with both MMPs and TIMPs. Since they bind and activate MMPs at their surfaces, the net result is a very controlled pericellular localization of MMP activities by MSCs.

Inducible expression of neurotrophic factors by mesenchymal progenitor cells derived from traumatically injured human muscle

Peripheral nerve damage frequently accompanies musculoskeletal trauma and repair of these nerves could be enhanced by the targeted application of neurotrophic factors (NTFs), which are typically expressed by endogenous cells that support nerve regeneration. Injured muscle tissues express NTFs to promote reinnervation as the tissue regenerates, but the source of these factors from within the muscles is not fully understood. We have previously identified a population of mesenchymal progenitor cells (MPCs) in traumatized muscle tissue with properties that support tissue regeneration, and our hypothesis was that MPCs also secrete the NTFs that are associated with muscle tissue reinnervation. We determined that MPCs express genes associated with neurogenic function and measured the protein-level expression of specific NTFs with known functions to support nerve regeneration. We also demonstrated the effectiveness of a neurotrophic induction protocol to enhance the expression of the NTFs, which suggests that the expression of these factors may be modulated by the cellular environment. Finally, neurotrophic induction affected the expression of cell surface markers and proliferation rate of the MPCs. Our findings indicate that traumatized muscle-derived MPCs may be useful as a therapeutic cell type to enhance peripheral nerve regeneration following musculoskeletal injury.

Mesenchymal stem cell therapy for attenuation of scar formation during wound healing

Scars are a consequence of cutaneous wound healing that can be both unsightly and detrimental to the function of the tissue. Scar tissue is generated by excessive deposition of extracellular matrix tissue by wound healing fibroblasts and myofibroblasts, and although it is inferior to the uninjured skin, it is able to restore integrity to the boundary between the body and its environment. Scarring is not a necessary process to repair the dermal tissues. Rather, scar tissue forms due to specific mechanisms that occur during the adult wound healing process and are modulated primarily by the inflammatory response at the site of injury. Adult tissue-derived mesenchymal stem cells, which participate in normal wound healing, are trophic mediators of tissue repair. These cells participate in attenuating inflammation in the wound and reprogramming the resident immune and wound healing cells to favor tissue regeneration and inhibit fibrotic tissue formation. As a result, these cells have been considered and tested as a likely candidate for a cellular therapy to promote scar-less wound healing. This review identifies specific mechanisms by which mesenchymal stem cells can limit tissue fibrosis and summarizes recent in vivo studies where these cells have been used successfully to limit scar formation.