Sex- and Gender-specific Analysis in Orthopaedic Studies

A bibliometric analysis of the top 50 cited studies related to acromioclavicular joint instability

Background

Acromioclavicular joint (ACJ) injury is a common orthopaedic condition accounting for over 40 % of all shoulder injuries. The purpose of this study is to assess the research trends and characteristics of the top 50 cited articles on ACJ instability.

Methods

A systematic search was conducted in Web of Science to identify articles primarily related to ACJ injury or instability. Characteristics including citation number, country of origin, journal and institution of publication, impact factor, authorship, level of evidence, patient demographics, and study type were analyzed and recorded.

Results

Research output on ACJ instability has been steadily increasing, with the top 50 cited studies predominantly presenting Level IV evidence. These studies primarily focused on treatment outcomes which included predominantly male patients and exhibited a large variation in citation counts. The American Journal of Sports Medicine was the most productive journal, and the USA was the most productive nation.

Conclusion

There is an increasing number of publications in the ACJ instability literature, primarily concentrated in a few institutions and journals, and focusing mainly on treatment outcomes. A significant portion of these publications are of low scientific quality, and there is a notable lack of research on outcomes for females.

Inclusion of Sex and Gender to Improve the State of the Science in Women's Health

ABSTRACT

The influence of sex and gender-related factors on health and disease at all levels of scale, across all health conditions, and throughout the entire life course is increasingly clear. A series of policies instituted by the National Institutes of Health (NIH) that require researchers to include appropriate populations and to analyze the data accordingly have strengthened the evidence base around the health of women. Translating these advances to the entire research ecosystem can catalyze rigorous biomedical discovery that can improve health. We encourage journals, publishers, and funders to align their policies and expectations regarding sex and gender considerations in research with those of the NIH and other international funding agencies.

Sex-specific analysis in patients undergoing Talar OsteoPeriostic grafting from the Iliac Crest (TOPIC) for large osteochondral lesions of the talus

PURPOSE

The purpose of the present study is to assess the gender-specific differences in the presentation and outcomes following Talar OsteoPeriostic grafting from the Iliac Crest (TOPIC) between male and female patients.

METHODS

A prospective comparative analysis was performed comparing consecutive female and male patients having been treated by the press-fit TOPIC procedure. Clinical comparative assessment preoperatively and at 12 months of follow-up included determination of the Numeric Rating Scale (NRS) scores for pain during walking (primary outcome), at rest and during stair-climbing. The Foot and Ankle Outcome Score (FAOS) was also assessed. A computed tomography (CT) scan was performed for lesion size, morphology and localization determination preoperatively as well as 10-12 weeks postoperatively to assess the union of the osteotomy site and at 1 year postoperatively to assess consolidation of the graft as well as intra-graft cyst development.

RESULTS

A total of 48 patients (30 women, 18 men) were eligible for inclusion. Both men and women demonstrated significant functional improvements postoperatively concerning the clinical outcomes with no significant differences between men and women (n.s.) except for a significantly greater improvement in postoperative FAOS pain scores in women. Men presented with OLTs significantly larger in both surface area (208 mm2 for males versus 155 mm2 for females, p < 0.05) as well as lesion volume (3.0 cm3 for males versus 1.8 cm3 for females, p < 0.05). At 1-year postoperatively, all patients showed graft consolidation. Cyst formation was present in 11 females (37% of the group) and 10 males (59% of the group), respectively (n.s.).

CONCLUSION

Both males and females showed clinically relevant improvements in the clinical outcomes after undergoing the TOPIC procedure with significant differences in preoperative lesion size. The TOPIC procedure is a good treatment strategy for large OLTs in both men and women.

LEVEL OF EVIDENCE

Level III, comparative prospective clinical cohort.

Systematic Review of Gender and Sex Terminology Use in Arthroplasty Research: There Is Room for Improvement

BACKGROUND

There is increasing appreciation of the distinction between gender and sex as well as the importance of accurately reporting these constructs. Given recent attention regarding transgender and gender nonconforming (TGNC) and intersex identities, it is more necessary than ever to understand how to describe these identities in research. This study sought to investigate the use of gender- and sex-based terminology in arthroplasty research.

METHODS

The 5 leading orthopaedic journals publishing arthroplasty research were reviewed to identify the first twenty primary clinical research articles on an arthroplasty topic published after January 1, 2022. Use of gender- or sex-based terminology, whether use was discriminate, and whether stratification or adjustment based on gender or sex was performed, were recorded.

RESULTS

There were 98 of 100 articles that measured a construct of gender or sex. Of these, 15 articles used gender-based terminology, 45 used sex-based terminology, and 38 used a combination of gender- and sex-based terminology. Of the 38 articles using a combination of terminology, none did so discriminately. All articles presented gender and sex as binary variables, and 2 attempted to explicitly define how gender or sex were defined. Of the 98 articles, 31 used these variables for statistical adjustments, though only 6 reported stratified results.

CONCLUSIONS

Arthroplasty articles infrequently describe how gender or sex was measured, and frequently use this terminology interchangeably. Additionally, these articles rarely offer more than 2 options for capturing variation in sex and gender. Future research should be more precise in the treatment of these variables to improve the quality of results and ensure findings are patient-centered and inclusive.

Investigating and Practicing Orthopedics at the Intersection of Sex and Gender: Understanding the Physiological Basis, Pathology, and Treatment Response of Orthopedic Conditions by Adopting a Gender Lens: A Narrative Overview

In the biomedical field, the differentiation between sex and gender is crucial for enhancing the understanding of human health and personalizing medical treatments, particularly within the domain of orthopedics. This distinction, often overlooked or misunderstood, is vital for dissecting and treating musculoskeletal conditions effectively. This review delves into the sex- and gender-specific physiology of bones, cartilage, ligaments, and tendons, highlighting how hormonal differences impact the musculoskeletal system's structure and function, and exploring the physiopathology of orthopedic conditions from an epidemiological, molecular, and clinical perspective, shedding light on the discrepancies in disease manifestation across sexes. Examples such as the higher rates of deformities (adolescent idiopathic and adult degenerative scoliosis and hallux valgus) in females and osteoporosis in postmenopausal women illustrate the critical role of sex and gender in orthopedic health. Additionally, the review addresses the morbidity-mortality paradox, where women, despite appearing less healthy on frailty indexes, show lower mortality rates, highlighting the complex interplay between biological and social determinants of health. Injuries and chronic orthopedic conditions such osteoarthritis exhibit gender- and sex-specific prevalence and progression patterns, necessitating a nuanced approach to treatment that considers these differences to optimize outcomes. Moreover, the review underscores the importance of recognizing the unique needs of sexual minority and gender-diverse individuals in orthopedic care, emphasizing the impact of gender-affirming hormone therapy on aspects like bone health and perioperative risks. To foster advancements in sex- and gender-specific orthopedics, we advocate for the strategic disaggregation of data by sex and gender and the inclusion of "Sexual Orientation and Gender Identity" (SOGI) data in research and clinical practice. Such measures can enrich clinical insights, ensure tailored patient care, and promote inclusivity within orthopedic treatments, ultimately enhancing the precision and effectiveness of care for diverse patient populations. Integrating sex and gender considerations into orthopedic research and practice is paramount for addressing the complex and varied needs of patients. By embracing this comprehensive approach, orthopedic medicine can move towards more personalized, effective, and inclusive treatment strategies, thereby improving patient outcomes and advancing the field.

Rates of Reporting and Analyzing Patient Sex in Sports Medicine Research: A Systematic Review

BACKGROUND

Sex differences in sports medicine are well documented. However, no studies to date have reviewed the rate at which sex is reported and analyzed in the athlete-specific orthopaedic sports medicine literature.

PURPOSE

To determine the rates of reporting and analyzing patient sex in athlete-specific sports medicine literature.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

Articles published by the 3 journals of the AOSSM (American Journal of Sports Medicine [AJSM], Orthopaedic Journal of Sports Medicine, and Sports Health: A Multidisciplinary Approach) between 2017 and 2021 were considered for inclusion. Original sports medicine research studies that isolated athletes were included. Studies that isolated sports that are predominantly single sex at the college and/or professional levels (football, baseball, softball, and wrestling) were excluded.

RESULTS

Of the 5140 publications screened, 559 met the inclusion criteria. In total, 93.9% of all studies reported patient sex, and 34.7% of all studies analyzed patient sex. However, 143 studies only included males and 50 studies only included females (n = 193). When excluding these single-sex studies, analysis of the remaining 366 studies found that the rate of sex-specific analysis increased to 53.0%. Rates of reporting patient sex did not significantly differ by journal or by year. Similarly, rates of analyzing patient sex did not differ by year, but Sports Health analyzed sex the most frequently, and AJSM analyzed sex the least frequently (P = .002). Studies that isolated college (84.1%), youth (66.7%), or recreational (52.6%) athletes analyzed sex at or above the overall rate of 53.0%, but studies of elite athletes (35.7%) tended to analyze sex less frequently.

CONCLUSION

Patient sex is well reported in the athlete-specific sports medicine literature (93.9% of included studies reported sex), demonstrating that most studies include sex as a demographic variable. However, patient sex was analyzed only in 53.0% of studies that included both male and female patients. Given that athlete-specific sex differences are known to exist within the field of sports medicine, many studies that could benefit from using patient sex as a variable for analysis likely fail to do so.

American Shoulder and Elbow Surgeons score: what does it tell us about patients selecting operative treatment of a rotator cuff injury?

Background

As shared decision-making rises in importance and minimum clinically important differences become benchmarks for treatment success or failure based on the increased usage of patient-reported outcomes, it is important to understand the breadth of starting points for patients as that should affect the interpretation of individual postoperative score changes.

Methods

This is a retrospective data review of prospectively collected American Shoulder and Elbow Surgeons (ASES) score of patients electing to undergo rotator cuff repair with 1-year follow-up. A residual improvement: possible to achieve ratio (RIPAR) was calculated to demonstrate what percent of maximal possible improvement was gained at 1 year. A minimal clinically important difference (MCID) of 12 was used.

Results

Three hundred thirty-five patients with an age range of 32-79 years form the population. Baseline ASES score ranged from 0 to 97.5, with a mean of 47.8. At 1 year, the mean was 84.7 (range, 30-100). There was no statistical difference by age, but men reported more overall preoperative dysfunction than women (50.3 vs. 44.1, P < .001). The RIPAR was on average 67%. Seventy-eight percent of the population demonstrated RIPAR scores >50% which showed improvement of over half of their preoperative deficit. Eighty-nine percent of patients achieved a positive MCID and 3% achieved a negative MCID.

Conclusions

The ASES scores showed a broad range of baseline scores for patients choosing to undergo rotator cuff repair highlighting the need for individual patient rather than population review of patient-reported outcome measures. As shared decision-making is taking on a larger role in clinical care, it is important to counsel patients accurately. Evaluating the ASES score by MCID and maximal possible improvement provides different population perspectives with the concept of RIPAR allowing for personalization of decision-making on the individual patient level.

Autologous Osteochondral Transplantation for Osteochondral Lesions of the Talus-Does Sex Play a Role?

Autologous osteochondral transplantation (AOT) is used in the treatment of osteochondral lesions (OCL) of the talus. The purpose of this study was to compare the differences in the presentation of talar OCLs and outcomes following AOT between male and female patients. Eighty-seven consecutive patients, ages 16 to 65 years, who underwent AOT were retrospectively reviewed. Patients were divided into 2 groups based on sex. Demographic data and OCL defect characteristic data were recorded. Functional outcomes were assessed pre- and postoperatively using the Foot and Ankle Outcome Score (FAOS). The Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score was used to assess cartilage incorporation. Fifty-six (64%) males and 31 (36%) females with mean clinical follow-up of 47.2 months were included in this study. OCL defect size was significantly larger in male patients (112.8 mm²) when compared with female patients (88.7 mm²) (p < .001). Male patients presented with a lesion associated with a recognized trauma (p < .006) when compared with female patients who typically presented with associated chronic ankle instability. Mean FAOS improved pre- to postoperatively from 50 to 81 (p < .001) with a statistically significant increase found in male patients (p < .001). The mean MOCART score was 82.1 in male and 86.7 female patients (p < .001). Our study demonstrates potential gender-related differences in the presentation and mechanism of injury in the development of OCLs. It is also not unreasonable to suggest that there may also be differences in treatment and rehabilitation strategies to reduce the risk of developing OCLs in men and women.

Sports-Related Shoulder Injuries Among Female Athletes

PURPOSE OF REVIEW

The objectives of this review are to explore the recent literature evaluating sports-related shoulder injuries among female athletes.

RECENT FINDINGS

Recent literature has highlighted sex-related differences in injury trends and patterns among athletes. Increased participation of women in both recreational and professional sports has resulted in increased exposure to injury. While men experience greater rates of shoulder injury overall, women tend to experience more overuse-related injuries. Evidence also suggests women are more susceptible to shoulder laxity and rotator cuff tears. In comparison to their male counterparts, women note poorer function, increased pain, and decreased activity level following shoulder injuries. Women may also be more likely to experience worse outcomes following surgical intervention. Sex-related differences in injury patterns and outcomes results from a combination of molecular and environmental influences, including hormone pathways, shoulder morphology, and differing rates of participation in, and athletic regulations among, certain sports. Sex-related differences occur in how athletes sustain, experience, and recover from sports-related injuries. A comprehensive understanding of sex-related injuries enhances clinical decision making, treatment, and recovery. Further research is needed to clarify sex as an independent variable when evaluating sports-related shoulder injuries.

In Vivo Anatomical Research by 3D CT Reconstruction Determines Minimum Acromiohumeral, Coracohumeral, and Glenohumeral Distances in the Human Shoulder: Evaluation of Age and Sex Association in a Sample of the Chinese Population

Accurate measurement of the minimum distance between bony structures of the humeral head and the acromion or coracoid helps advance a better understanding of the shoulder anatomical features. Our goal was to precisely determine the minimum acromiohumeral distance (AHD), coracohumeral distance (CHD), and glenohumeral distance (GHD) in a sample of the Chinese population as an in vivo anatomical analysis. We retrospectively included 146 patients who underwent supine computed tomography (CT) examination of the shoulder joint. The minimum AHD, CHD, and GHD values were quantitatively measured using three-dimensional (3D) CT reconstruction techniques. The correlation between minimum AHD, CHD, and GHD value and age with different sexes was evaluated using Pearson Correlation Coefficient. The mean value of minimum AHD in males was greater than that in females (male 7.62 ± 0.98 mm versus female 7.27 ± 0.86 mm, p = 0.046). The CHD among different sexes differed significantly (male 10.75 ± 2.40 mm versus female 8.76 ± 1.38 mm, p < 0.001). However, we found no statistical differences in GHD with different sexes (male 2.00 ± 0.31 mm versus female 1.96 ± 0.36 mm, p > 0.05). In terms of age correlation, a negative curve correlation existed between age and AHD among the different sexes (male R2 = 0.124, p = 0.030, female R2 = 0.112, p = 0.005). A negative linear correlation was found in CHD among the different sexes (male R2 = 0.164, p < 0.001, female R2 = 0.122, p = 0.005). There were no differences between age and minimum GHD in both sexes. The 3D CT reconstruction model can accurately measure the minimum AHD, CHD, and GHD value in vivo and is worthy of further investigation for standard clinical anatomical assessment. Aging may correlate with AHD and CHD narrowing for both sexes.

Impact of gender on outcomes following single-level anterior lumbar interbody fusion

Background

There have been a multitude of studies attempting to identify the relationship between gender and postoperative outcomes; however, few studies have examined how this relationship may affect outcomes after anterior lumbar interbody fusion (ALIF) surgery. We aim to better characterize the impact that self-reported gender may have on patient reported outcome measures (PROMs) and achievement rates of minimum clinically important difference (MCID) after ALIF.

Methods

A retrospective database of a single spine surgeon was searched for patients who had undergone single-level ALIF. Indications for surgery including acute trauma, infection, or malignancy were excluded. The population was separated into cohorts by self-reported gender, female or male. PROMs were recorded and compared within groups to their preoperative baselines and between groups. MCID achievement rate was compared between groups.

Results

140 patients were identified for this study, with 68 patients self-identifying as female gender. The male gender cohort was found to have a significantly greater prevalence of hypertension (p = 0.018). Both cohorts showed significant improvement during at least one or more postoperative time points for each evaluated outcome measure (p ≤ 0.048, all). No significant difference in mean PROM scores was noted between cohorts at any time point for any measured outcome. The female gender cohort had significantly greater MCID achievement rates for visual acuity scale (VAS) back pain overall and at the 6-month time point (p ≤ 0.043, both). The female gender cohort also had significantly greater achievement of MCID at the 1-year time point for VAS leg pain (p = 0.017).

Conclusion

Both female and male gender cohorts demonstrated significant improvement in all outcomes measured at one or more postoperative time points. Postoperative outcomes did not differ by gender. MCID achievement was more common in female patients. Female patients may experience more tangible clinical improvement after ALIF compared to male patients.

Sex Differences in Utilization and Perioperative Outcomes of Arthroscopic Rotator Cuff Repair

Background

As the volume and proportion of patients treated arthroscopically for rotator cuff repair increases, it is important to recognize sex differences in utilization and outcomes.

Methods

Patients who underwent arthroscopic rotator cuff repair between 2010 and 2019 were identified in the American College of Surgeons National Surgical Quality Improvement Program registry. Baseline demographic and clinical characteristics were collected, and information concerning utilization, operative time, length of hospital stay, days from operation to discharge, readmission, and adverse events were analyzed by sex.

Results

Of 42,443 included patients, 57.7% were male and 42.3% were female. Comparably, females were generally older (P < .001) and less healthy as indicated by American Society of Anesthesiologists class (P < .001) and rates of obesity (52.0% vs. 47.8%, P < .001), chronic obstructive pulmonary disease (4.0% vs. 2.7%, P < .001), and steroid use (2.7% vs. 1.6%, P < .001). Females experienced shorter operative times (mean difference [MD] 11.5 minutes, P < .001), longer hospital stays (MD 0.03 days, P < .001), longer times from operation to discharge (MD 0.03 days, P < .001), and more minor adverse events (odds ratio [OR], 1.75; 95% confidence interval [CI], 1.24-2.47) after baseline adjustment. Conversely, rates of serious adverse events (OR, 0.69; 95% CI, 0.55-0.86) and readmissions (OR, 0.88; 95% CI, 0.66-0.97) were lower among females. Disparities in utilization increased over the study period (P = .008), whereas length of stay (P = .509) and adverse events (P = .967) remained stable.

Conclusion

Sex differences among patients undergoing arthroscopic rotator cuff repair are evident, indicating the need for further research to understand and address the root causes of inequality and optimize care for all.

Sex-related differences in stemless total shoulder arthroplasty

Background

Methods

Results

Conclusion

Male Sex Is Associated with Higher Mortality and Increased Risk for Complications after Surgical Treatment of Proximal Humeral Fractures

AIMS

The best surgical treatment of multi-fragmentary proximal humeral fractures in the elderly is a highly controversial topic. The aim of this study is to assess for sex-related differences regarding mortality and complications after reverse total shoulder arthroplasty (RTSA) and locking plate fixation (LPF).

PATIENTS AND METHODS

All patients from the largest German healthcare insurance (26.5 million policy holders) above the age of 65 years that were treated with LPF or RTSA after a multi-fragmentary proximal humerus fracture between January 2010 and September 2018 were included. Multivariable Cox regression models were used to assess the association of sex with overall survival, major adverse events and surgical complications.

RESULTS

A total of 8264 (15%) men and 45,707 (85%) women were followed up for a median time of 52 months. After 8 years, male patients showed significantly higher rates for death (65.8%; 95% CI 63.9-67.5% vs. 51.1%; 95% CI 50.3-51.9%; p < 0.001) and major adverse events (75.5%; 95% CI 73.8-77.1% vs. 61.7%; 95% CI 60.9-62.5%; p < 0.001). With regard to surgical complications, after adjustment of patient risk profiles, there were no differences between females and males after LPF (p > 0.05), whereas men showed a significantly increased risk after RTSA (HR 1.86; 95% CI 1.56-2.22; p < 0.001) with more revision surgeries performed (HR 1.76, 95% CI 1.46-2.12; p < 0.001) compared to women.

CONCLUSION

The male sex is an independent risk factor for death and major adverse events after both LPF and RTSA. An increased risk for surgical complications after RTSA suggests that male patients benefit more from LPF. Sex should be considered before making treatment decisions.

Gender-Specific Response in Pain and Function to Biologic Treatment of Knee Osteoarthritis: A Gender-Bias-Mitigated, Observational, Intention-to-Treat Study at Two Years

Knee osteoarthritis is a major cause of disability worldwide. Newer modalities of treatment with less morbidity, such as intra-articular injection of microfragmented fat (MFAT), are showing promise. We report on our novel observation that women show a greater improvement in pain and function to MFAT than men. Traditionally, women have been underrepresented in studies and studies with both sexes regularly fail to analyze the results by sex. To mitigate for this bias and quantify it, we describe a technique using reproducible statistical analysis and replicable results with Open Access statistical software R to calculate the magnitude of this difference. Genetic, hormonal, environmental, and age factors play a role in our observed difference between the sexes. There is a need for further studies to identify the molecular basis for this difference and be able to utilize it to improve outcome for both women and men.

Sex-Specific Analysis Is Lacking in Abstracts Presented at Arthroscopy Association of North America and American Orthopaedic Society for Sports Medicine Annual Meetings From 2016 to 2019

Purpose

To evaluate the presence of sex-specific analysis (SSA) in abstracts accepted for podium presentation at the Arthroscopy Association of North America (AANA) and American Orthopaedic Society for Sports Medicine (AOSSM) annual meetings from 2016 to 2019.

Methods

Abstracts accepted for podium presentation at the AANA and AOSSM annual meetings from 2016 to 2019 were selected for review. Studies that included sex as a variable in a multifactorial statistical model were considered to have performed adequate SSA. Secondary data collected included whether the abstract had a female lead or senior author, the degrees of the female authors, and the anatomic focuses of studies with SSA.

Results

Of the 891 total abstracts accepted for podium presentation at the AANA and AOSSM annual meetings from 2016 to 2019, 90 (10%) included SSA. There were 284 AANA abstracts, 24 (8%) of which reported SSA. Of the 607 AOSSM abstracts, 66 (11%) reported SSA. There were 43 female first authors (15%) and 33 female senior authors (12%) of the AANA abstracts compared with 92 female first authors (15%) and 39 female senior authors (6%) of the AOSSM abstracts. Of the 891 total abstracts, 135 (15%) listed a female lead author and 72 (8%) had a female senior author. Of the 135 female first authors, 92 (68%) had an M.D., whereas 40 of the 72 female senior authors (56%) had an M.D. Analysis of all abstracts combined showed a positive correlation between SSA and a female first author (Pearson correlation coefficient = 0.035, P = .147), as well as between SSA and a female senior author (Pearson correlation coefficient = 0.052, P = .059).

Conclusions

From 2016 to 2019, only 10% of abstracts accepted for podium presentation at the AANA and AOSSM annual meetings included SSA. Altogether, women represented 15% of first authors and 8% of senior authors.

Clinical Relevance

This study highlights the low percentage of SSA in abstracts presented at the AANA and AOSSM annual meetings from 2016 to 2019. Future studies should attempt to perform SSA when relevant to better evaluate differences in outcomes between male and female patients.