Abstract
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.
Keywords: Sex differences, Arthroscopic rotator cuff repair, Shoulder, Utilization, Outcomes, Trends, NSQIP
Although healthcare providers strive for equal treatment of all patients, research suggests that implicit bias may disproportionately affect patient care based on race, ethnicity, sex, and socioeconomic status.1,2,21,28 In particular, several studies examining sex differences among patients undergoing orthopedic surgeries report that females present in more advanced disease states, which is subjectively reflected by a greater degree of baseline pain-related physical dysfunction.38,47 Moreover, female patients report higher perioperative pain scores and may be at greater risk for chronic opioid use following surgery.38,40 Whether sex differences across patient-reported outcome measures are secondary to differences in delivery of patient care founded in physician bias or simply due to incongruent baseline morphology remains a topic of discussion.43 Nevertheless, it is critical to recognize such differences as they may influence clinical decision-making and patient expectations following surgical treatment.31
Sex differences among those undergoing arthroscopic rotator cuff repair are particularly important to recognize due to the increasing popularity of the procedure. Advances in minimally invasive surgical techniques have allowed surgeons to repair an increasing proportion of rotator cuff tears arthroscopically, and a recent national database study revealed that the volume of total rotator cuff repairs increased by 188% between 2007 and 2015.14,16 Sabo et al41 studied patient-reported outcomes between men and women undergoing rotator cuff surgery and found no differences in functional outcomes or pain scores within 12 months postoperatively. While this study analyzed sex differences in a small subset of patients undergoing arthroscopic rotator cuff repair, there remains an absence of studies examining this topic utilizing a large, national cohort of patients.
The purpose of this study was, therefore, to retrospectively analyze a national database to investigate sex-related differences in utilization and several perioperative outcomes among patients following arthroscopic rotator cuff repair. Additionally, sex differences in total operative time, length of total hospital stay, and time from surgery to discharge were examined.
Materials and methods
This retrospective cohort study was conducted using data from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database for the years 2010-2019. The ACS-NSQIP is a nationally validated, outcomes-based registry containing voluntarily provided data concerning more than 300 perioperative variables from over 700 participating medical institutions, including academic and private, community and tertiary, and inpatient and outpatient centers.24,36,45 No attention is paid to payer type to promote a reasonably representative sample of United States payer types, including private, public, and self-pay patients. Baseline characteristics and 30-day perioperative outcomes are recorded directly from the electronic medical record by a team of well-trained surgical clinical reviewers through a process consistently shown to demonstrate excellent inter-rater reliability.8,9,46 As data from the ACS-NQSIP is deidentified and relies on no direct patient contact, this study was granted institutional review board approval by Mass General Brigham IRB Protocol #2021P001230.
Adult patients aged 18 years or older who underwent primary arthroscopic rotator cuff repair were identified using current procedural terminology code 29827. Baseline demographic (patient age, sex, body mass index (BMI), race, smoking status) and clinical (American Society of Anesthesiologists [ASA] class, diabetes mellitus, steroid use for chronic condition, severe chronic obstructive pulmonary disease [COPD], congestive heart failure [CHF], hypertension requiring medication) data were recorded. Collected data were subsequently analyzed to determine sex-related differences in (1) utilization rates, (2) total operative time, (3) length of total hospital stay, (4) days from operation to discharge, (5) rates of 30-day readmission, and (6) rates of 30-day adverse events. Adverse events were further classified as serious or minor in accordance with previous ACS-NSQIP analyses.10,27,29 Explicitly, serious adverse events included death, reoperation, pulmonary complications (unplanned intubation, mechanical ventilation >48 hours), pneumonia, cardiac complications (cardiac arrest, myocardial infarction), renal complications (progressive renal insufficiency, acute renal failure), thromboembolic complications (deep vein thrombosis /thrombophlebitis, pulmonary embolism), deep wound complications (deep incisional surgical site infection [SSI], joint space infection, wound dehiscence), and sepsis, while minor adverse events consisted of superficial SSI and urinary tract infection. Sex-specific trends in procedure utilization rates, length of stay, and serious adverse events over time were also assessed.
Statistical analysis
Statistical analyses were conducted using SAS software version 9.4 (SAS Institute, Cary, NC, USA). Continuous variables are reported as means and standard deviations, and categorical variables are reported as percentages. Baseline unadjusted analyses were performed using Student t-tests for continuous variables and Pearson chi-square or Fisher’s exact tests for categorical variables as appropriate to determine sex-related differences. To adjust for differences in baseline demographic and clinical characteristics other than sex, multivariate analyses were performed using binomial logistic regression, and results are reported as odds ratios (ORs), mean differences (MDs), and rate ratios with 95% confidence intervals (CIs). Additionally, sex-by-year interactions were added to the models via Cochran–Armitage Trend testing to assess trends in disparities over time.3,11 P values < .05 were considered significant.
Results
In total, 42,443 patients undergoing arthroscopic rotator cuff repair between 2010 and 2019 met the inclusion criteria, including 24,483 (57.7%) male and 17,960 (42.3%) female patients. Overall, female patients were older (P < .001) and less healthy than their male counterparts as indicated by higher ASA class (P < .001) and greater rates of obesity (52.0% vs. 47.8%, P < .001), history of COPD (4.0% vs. 2.7%, P < .001), and steroid use for chronic conditions (2.7% vs. 1.6%, P < .001). Rates of smoking within one year prior to surgery were lower among females, however (14.2% vs. 15.6%, P < .001). Notably, the female cohort also consisted of a greater proportion of Black or African American patients than the male cohort (12.7% vs. 8.5%, P < .001). No differences between groups were observed for rates of diabetes mellitus, history of CHF, or hypertension requiring medication. A complete summary of baseline demographic and clinical characteristics is provided in Table I.
Table I.
Demographic and clinical characteristics of male and female patients undergoing arthroscopic rotator cuff repair.
| Variables | Total N = 42,443(%) | Female N = 17,960(%) | Male N = 24,483(%) | P value |
|---|---|---|---|---|
| Age group (y) | <.001∗ | |||
| 0-24 | 203 (0.5) | 60 (0.3) | 143 (0.6) | |
| 25-34 | 719 (1.7) | 203 (1.1) | 516 (2.1) | |
| 35-44 | 3223 (7.6) | 1112 (6.2) | 2111 (8.6) | |
| 45+ | 38,297 (90.2) | 16,584 (92.3) | 21,713 (88.7) | |
| Race | <.001∗ | |||
| Black or African American | 4353 (10.3) | 2280 (12.7) | 2073 (8.5) | |
| White | 38,090 (89.7) | 15,680 (87.3) | 22,410 (91.5) | |
| BMI category | <.001∗ | |||
| Normal (≤24.9 kg/m2) | 6559 (15.6) | 3554 (19.9) | 30,05 (12.4) | |
| Overweight (25.0-29.9 kg/m2) | 14,706 (34.9) | 5018 (28.1) | 9688 (39.8) | |
| Obese (≥30.0 kg/m2) | 20,910 (49.6) | 9273 (52.0) | 11,637 (47.8) | |
| Diabetes mellitus | .884∗ | |||
| No | 35,461 (83.5) | 15,000 (83.5) | 20,461 (83.6) | |
| Yes | 6982 (16.5) | 2960 (16.5) | 4022 (16.4) | |
| ASA class | <.001∗ | |||
| 1 | 3269 (7.7) | 1049 (5.8) | 2220 (9.1) | |
| 2 | 24,310 (57.3) | 10,271 (57.2) | 14,039 (57.4) | |
| 3 | 14,844 (35.0) | 6632 (36.9) | 8212 (33.6) | |
| Smoker (within past 1 y) | <.001∗ | |||
| No | 36,082 (85.0) | 15,413 (85.8) | 20,669 (84.4) | |
| Yes | 6361 (15.0) | 2547 (14.2) | 3814 (15.6) | |
| History of severe COPD | <.001∗ | |||
| No | 41,059 (96.7) | 17,234 (96.0) | 23,825 (97.3) | |
| Yes | 1384 (3.3) | 726 (4.0) | 658 (2.7) | |
| History of CHF | .758∗ | |||
| No | 42,382 (99.9) | 17,933 (99.8) | 24,449 (99.9) | |
| Yes | 61 (0.1) | 27 (0.2) | 34 (0.1) | |
| Hypertension requiring medication | .373∗ | |||
| No | 22,392 (52.8) | 9430 (52.5) | 12,962 (52.9) | |
| Yes | 20,051 (47.2) | 8530 (47.5) | 11,521 (47.1) | |
| Steroid use for chronic condition | <.001∗ | |||
| No | 41,567 (97.9) | 17,470 (97.3) | 24,097 (98.4) | |
| Yes | 876 (2.1) | 490 (2.7) | 386 (1.6) |
ASA, American Society of Anesthesiologists; BMI, body mass index; CHF, congestive heart failure; COPD, chronic obstructive pulmonary disease.
P-values < .05 were considered statistically significant.
Chi-square test.
Perioperative outcomes of arthroscopic rotator cuff repair
Significant sex-related differences in total operative time, length of total hospital stay, and days from operation to discharge following arthroscopic rotator cuff repair were noted on unadjusted analyses (Table II). Despite achieving shorter operative times than male patients (83.1 ± 43.4 vs. 94.1 ± 47.1 minutes, P < .001), female patients demonstrated longer total hospital stays (0.20 ± 3.1 vs. 0.14 ± 1.7 days, P < .001) and greater time from operation to discharge (0.16 ± 1.3 vs. 0.12 ± 1.5 days, P < .001) compared to male patients. Female patients were less likely to experience serious adverse events (0.67% vs. 0.95%, P = .002), as rates of reoperation (0.21% vs. 0.33%, P = .016), myocardial infarction (0.03% vs. 0.09%, P = .017), deep incisional SSI (0.01 % vs. 0.05%, P = .034), and joint space infection (0.01% vs. 0.04%, P = .031) were higher among males. In contrast, overall rates of minor adverse events were higher among females (0.43% vs. 0.23%, P < .001), though this was apparently a reflection of an increased incidence of urinary tract infection (0.34% vs. 0.09%, P < .001) as there was no difference between males and females in incidence of superficial SSI (0.09% vs. 0.14%, P = .140).
Table II.
Comparison of outcomes between male and female patients following arthroscopic rotator cuff repair.
| Variables | Total N = 42,443(%) | Female N = 17,960(%) | Male N = 24,483(%) | P value |
|---|---|---|---|---|
| Total operation time | <.001§ | |||
| N | 42,403 | 17,944 | 24,459 | |
| Mean ± SD (minutes) | 89.5 ± 45.9 | 83.1 ± 43.4 | 94.1 ± 47.1 | |
| Length of total hospital stay | <.001§ | |||
| N | 42,433 | 17,957 | 24,476 | |
| Mean ± SD (days) | 0.2 ± 2.4 | 0.20 ± 3.1 | 0.14 ± 1.7 | |
| Days from operation to discharge | <.001§ | |||
| N | 42,443 | 17,960 | 24,483 | |
| Mean ± SD | 0.13 ± 1.4 | 0.16 ± 1.3 | 0.12 ± 1.5 | |
| Readmission | .166† | |||
| No | 40,503 (98.93) | 17,181 (99.01) | 23,322 (98.87) | |
| Yes | 437 (1.07) | 171 (0.99) | 266 (1.13) | |
| Serious adverse events | .002† | |||
| No | 42,090 (99.17) | 17,839 (99.33) | 24,251 (99.05) | |
| Yes | 353 (0.83) | 121 (0.67) | 232 (0.95) | |
| Death | .340‡∗ | |||
| No | 42,433 (99.98) | 17,954 (99.97) | 24,479 (99.98) | |
| Yes | 10 (0.02) | 6 (0.03) | 4 (0.02) | |
| Reoperation | .016† | |||
| No | 42,325 (99.72) | 17,923 (99.79) | 24,402 (99.67) | |
| Yes | 118 (0.28) | 37 (0.21) | 81 (0.33) | |
| Unplanned intubation | .949† | |||
| No | 42,419 (99.94) | 17,950 (99.94) | 24,469 (99.94) | |
| Yes | 24 (0.06) | 10 (0.06) | 14 (0.06) | |
| Ventilator >48 Hours | .778† | |||
| No | 42,430 (99.97) | 17,955 (99.97) | 24,475 (99.97) | |
| Yes | 13 (0.03) | 5 (0.03) | 8 (0.03) | |
| Pneumonia | .974† | |||
| No | 42,386 (99.87) | 17,936 (99.87) | 24,450 (99.87) | |
| Yes | 57 (0.13) | 24 (0.13) | 33 (0.13) | |
| Cardiac arrest | .142‡∗ | |||
| No | 42,436 (99.98) | 17,955 (99.97) | 24,481 (99.99) | |
| Yes | 7 (0.02) | 5 (0.03) | 2 (0.01) | |
| Myocardial infarction | .017† | |||
| No | 42,417 (99.94) | 17,955 (99.97) | 24,462 (99.91) | |
| Yes | 26 (0.06) | 5 (0.03) | 21 (0.09) | |
| Progressive renal insufficiency | .656‡∗ | |||
| No | 42,438 (99.99) | 17,957 (99.98) | 24,481 (99.99) | |
| Yes | 5 (0.01) | 3 (0.02) | 2 (0.01) | |
| Acute renal failure | .268‡∗ | |||
| No | 42,440 (99.99) | 17,960 (100.0) | 24,480 (99.99) | |
| Yes | 3 (0.01) | 0 (0.00) | 3 (0.01) | |
| DVT/Thrombophlebitis | .167† | |||
| No | 42,378 (99.85) | 17,938 (99.88) | 24,440 (99.82) | |
| Yes | 65 (0.15) | 22 (0.12) | 43 (0.18) | |
| Pulmonary embolism | .056† | |||
| No | 42,375 (99.84) | 17,939 (99.88) | 24,436 (99.81) | |
| Yes | 68 (0.16) | 21 (0.12) | 47 (0.19) | |
| Deep incisional SSI | .034† | |||
| No | 42,429 (99.97) | 17,958 (99.99) | 24,471 (99.95) | |
| Yes | 14 (0.03) | 2 (0.01) | 12 (0.05) | |
| Wound dehiscence | .729‡∗ | |||
| No | 42,435 (99.98) | 17,956 (99.98) | 24,479 (99.98) | |
| Yes | 8 (0.02) | 4 (0.02) | 4 (0.02) | |
| Joint space infection | .031‡∗ | |||
| No | 42,432 (99.97) | 17,959 (99.99) | 24,473 (99.96) | |
| Yes | 11 (0.03) | 1 (0.01) | 10 (0.04) | |
| Sepsis | .856† | |||
| No | 42,428 (99.96) | 17,954 (99.97) | 24,474 (99.96) | |
| Yes | 15 (0.04) | 6 (0.03) | 9 (0.04) | |
| Minor adverse events | <.001† | |||
| No | 42,309 (99.68) | 17,883 (99.57) | 24,426 (99.77) | |
| Yes | 134 (0.32) | 77 (0.43) | 57 (0.23) | |
| Superficial SSI | .140† | |||
| No | 42,393 (99.88) | 17,944 (99.91) | 24,449 (99.86) | |
| Yes | 50 (0.12) | 16 (0.09) | 34 (0.14) | |
| Urinary tract infection | <.001† | |||
| No | 42,359 (99.80) | 17,899 (99.66) | 24,460 (99.91) | |
| Yes | 84 (0.20) | 61 (0.34) | 23 (0.09) |
DVT, deep vein thrombosis; SD, standard deviation; SSI, surgical site infection.
Exact test.
Chi-square test.
Fisher’s exact test.
Negative binomial model.
After adjusting to control for age, race, BMI, ASA class, smoking status, history of COPD, and steroid use for chronic conditions, differences in perioperative outcomes between male and female patients remained significant. Compared to males, total operation time was 11.5 minutes shorter for females (P < .001), while length of total hospital stay (MD 0.03 days, P < .001) and days from operation to discharge (MD 0.03 days, P < .001) were also increased (Table III). Moreover, rates of readmission (OR, 0.80; 95% CI, 0.66-0.97; P = .025) and serious adverse events (OR, 0.69; 95% CI, 0.55-0.86; P = .001) were 20% and 31% lower among female than male patients, respectively, though rates of minor adverse events were 75% higher (OR, 1.75; 95% CI, 1.24-2.47; P = .001; Table IV).
Table III.
Adjusted analyses comparing perioperative outcomes between male and female patients undergoing arthroscopic rotator cuff repair.
| Outcomes | Sex | Adjusted rate ratio (95% CI) | P Value | Estimated mean difference |
|---|---|---|---|---|
| Total operation time | Female vs Male | 0.88 (0.88-0.89) | <.001 | −11.50 minutes |
| Length of total hospital stay | Female vs Male | 1.24 (1.13-1.36) | <.001 | 0.03 days |
| Days from operation to discharge | Female vs Male | 1.26 (1.16-1.38) | <.001 | 0.03 days |
CI, confidence interval.
Note: Adjusted for age, race, body mass index, American Society of Anesthesiologists class, smoking status, history of COPD, and steroid use for chronic condition.
Table IV.
Adjusted analyses comparing postoperative outcomes between male and female patients following arthroscopic rotator cuff repair.
| Outcomes | Gender | Adjusted OR (95% CI) | P Value |
|---|---|---|---|
| Readmission | Female vs Male | 0.80 (0.66-0.97) | .025 |
| Serious adverse events | Female vs Male | 0.69 (0.55-0.86) | .001 |
| Minor adverse events | Female vs Male | 1.75 (1.24-2.47) | .001 |
CI, confidence interval; OR, odds ratio.
Note: Adjusted for age, race, body mass index, American Society of Anesthesiologists class, smoking status, history of severe COPD, and steroid use for chronic condition.
Trends in arthroscopic rotator cuff repair
The proportion of arthroscopic rotator cuff repair procedures performed for male and female patients varied from year to year; however, analysis of trends in relative utilization rates revealed the proportion of procedures performed for female patients slightly decreased between 2010 and 2019 at an average rate of 0.011% annually (P = .008; Table V, Fig. 1). Length of total hospital stay decreased over the study period for both male (coefficient −0.10, P < .001) and female (coefficient −0.08, P < .001) patients, though disparities between sexes persisted (ptrend = 0.509). Additionally, rates of serious adverse events for male (coefficient 0.005, P = .900) and female (coefficient 0.007, P = .807) patients, as well as disparities between the two sexes (ptrend = 0.967), remained largely unchanged.
Table V.
Rates of arthroscopic rotator cuff repair utilization.
| Year | Total N | Female N (%) | Male N (%) |
|---|---|---|---|
| Total (2010-2019) | 42,433 | 17,960 (42.3) | 24,483 (57.7) |
| 2010 | 1128 | 482 (41.7) | 646 (57.3) |
| 2011 | 1481 | 608 (41.1) | 873 (58.9) |
| 2012 | 2193 | 966 (44.0) | 1227 (56.0) |
| 2013 | 2984 | 1325 (44.4) | 1659 (55.6) |
| 2014 | 3938 | 1669 (42.4) | 2269 (57.6) |
| 2015 | 4973 | 2108 (42.4) | 2865 (57.6) |
| 2016 | 5982 | 2592 (43.3) | 3390 (56.7) |
| 2017 | 6662 | 2825 (42.4) | 3837 (57.6) |
| 2018 | 6355 | 2597 (40.9) | 3758 (59.1) |
| 2019 | 6747 | 2788 (41.3) | 3959 (58.7) |
Figure 1.
Trends in relative utilization of arthroscopic rotator cuff repair among males and females between 2010 and 2019.
Discussion
The development of arthroscopic methods for rotator cuff repair has enabled surgeons to substantially increase procedural volume while maintaining excellent outcomes.14,16,30 Although arthroscopic repair has been shown to offer patients quicker recovery with potentially less pain and morbidity relative to more traditional open and mini-open techniques,19,20,48,49 whether males and females equitably benefit from such methodological advances remains uncertain. The present study therefore compared rates of utilization, operative time, length of hospital stay, readmission, and adverse events between sexes using the ACS-NSQIP registry. Between 2010 and 2019, female patients comprised a smaller proportion of arthroscopic rotator cuff repair procedures relative to male patients. Total operative time was shorter among females, though measures of length of total hospital stay and time from operation to discharge were each longer than for males. Moreover, female patients exhibited higher rates of minor adverse events within 30 days of surgery, whereas male patients were more likely to experience serious adverse events and readmission. As a secondary analysis, trends in relative utilization, length of total hospital stay, and rates of serious adverse events were examined. Results indicate the proportion of procedures performed for female patients slightly decreased over the study period, whereas both sexes experienced similar reductions in the length of total hospital stay, and rates of adverse events remained stable. These findings warrant the consideration of clinicians and researchers alike as they show sex-related disparities in utilization and perioperative outcomes exist as more than merely a reflection of differences in baseline demographic or clinical characteristics, highlighting the need for further research to identify root causes and address inequality in arthroscopic rotator cuff repair.
Numerous differences in baseline demographic and clinical characteristics were noted between male and female cohorts. Female patients were generally older and less healthy, exhibiting higher rates of obesity, COPD, and steroid use for chronic conditions than males. Racial differences were also noted, as the female cohort consisted of a relatively larger proportion of Black and African American patients. However, such inconsistencies did not explain disparities in perioperative outcomes. Instead, sex differences in total operative time, length of total hospital stay, time from operation to discharge, readmission, and incidence of serious and minor adverse events persisted even after adjusting for age, race, BMI, ASA class, smoking status, history of COPD, and steroid use for chronic conditions.
To our knowledge, this study is the first to explore sex differences in arthroscopic rotator cuff repair utilization and outcomes in a large, nationwide cohort of patients. Disparities identified herein build upon previous research comparing patient-reported outcomes between male and female patients, which has produced mixed findings to date. In a study of 283 patients, Daniels et al13 observed women to report higher pain and lower shoulder function scores than men both preoperatively and within 3 months following surgery, translating to increased need for narcotic pain medication. Nevertheless, women did achieve greater improvements than males in both scores following surgery, demonstrating the benefit of arthroscopic repair for female patients. In contrast, Sabo et al41 more recently demonstrated no significant differences in patient-reported pain or function at any timepoint within one year of surgery, though results may have been limited by a smaller sample size. Interestingly, the authors noted women were more likely to undergo rotator cuff repair on the dominant arm, have smaller tear size, and have full rotator cuff repair than men. However, the extent to which these factors impact patient-reported outcomes is a topic of debate. Rather, Wylie et al50 determined mental health to be more strongly associated with patient-reported outcomes than tear characteristics, and differences in gender-based societal norms concerning pain expression and activity demands have also been postulated as potential influences.13,39,41 Thus, though findings of the current study demonstrate significant sex differences in objective measures of total operative time, length of hospital stay, and rates of adverse events among a much larger patient cohort, the underlying factors responsible for such disparities remain to be fully understood.
It is interesting that female patients constituted a smaller percentage of arthroscopic rotator cuff repair procedures with growing disparity over the study period, particularly as women have been shown to display higher rates of multidirectional shoulder instability and generalized joint laxity which may predispose to rotator cuff injury.5,12,32 This supports the notion that shoulder pathology is not explained solely by sex-related anatomic differences but more likely stems from a complex interplay of multiple causes including the effects of sex hormones and inflammatory mediators.23 Genetic factors have also been implicated, as Figueiredo et al17 reported variation in collagen haplotype and dysregulation of matric metalloproteinases to impact injury risk in males and females, respectively. Moreover, the prevalence of asymptomatic rotator cuff pathology may differ between males and females, further contributing to differential need for arthroscopic rotator cuff repair.37 Another noteworthy finding of the present study was that although female patients experienced higher rates of minor adverse events within 30 days, women exhibited lower rates of serious adverse events and readmission compared to men even after adjusting for baseline characteristics. The greater rate of minor adverse effects among females is evidently driven by an increased incidence of urinary tract infection, and this difference is likely a consequence of anatomic and hormonal contributions that naturally place females at greater risk rather than secondary to surgical intervention. The finding that males experience a higher rate of severe adverse events is in accordance with previous literature demonstrating similarly increased risk of death, myocardial infarction, and sepsis following orthopedic procedures including total shoulder arthroplasty,25,42 lower extremity arthroplasty,35,44 and spine surgery.4,34 There are a number of possible explanations for these results. For example, various risk factors have been shown to differentially affect risk for myocardial infarction among males and females.33 Thus although analyses were adjusted for patient demographics and comorbidities, baseline risk for myocardial infarction may still be greater among men than women prior to surgery. Differences in joint space infection rates may stem from an increased risk for Cutibacterium acnes infection among males, as male gender is a known risk factor for C acnes infection particularly following shoulder procedures, with up to 71% of cases occurring in men.6 While there was insufficient data to delineate the reasons for differences in serious adverse event rates between male and female patients in the present study, it is not surprising that increased risk for severe adverse events was paired with higher rates of readmission among men.
There are several limitations to consider when interpreting the results of this study. Alhough the ACS-NSQIP registry is a high-quality source of nationwide data validated by clinically trained reviewers, patient outcomes are only followed for 30 days following surgery, limiting capture of complications beyond this period and potentially underestimating rates of postoperative adverse event. Moreover, rates of adverse events are only captured for patients who seek care at an institution participating in the ACS-NSQIP. Information concerning surgeon experience, preoperative assessment, hospital volume, and procedural details were not documented, nor were more detailed clinical characteristics such as size and chronicity of rotator cuff tear, number of tendons affected, and extent of arthritis. Thus, their potential impact on arthroscopic rotator cuff repair utilization and perioperative outcomes could not be assessed. Relatedly, variation in postoperative rehabilitation was not evaluated despite their potential to attenuate risk for certain complications (eg, deep vein thrombosis). As a consequence of the large number of patients included in this study, analyses may produce results that are statistically but not clinically significant. For example, the mean difference in time between operation and discharge between male and female patients was statistically significant but measured only 0.03 days. Nevertheless, the ACS-NSQIP database remains an excellent resource for analysis of surgical utilization and short-term outcomes.7,9,15,18,22,26
Conclusion
As the use of arthroscopic techniques for rotator cuff repair continues to rise, it is imperative to recognize and characterize differences in procedure utilization and perioperative outcomes across patient groups. The present study focuses specifically on sex differences and demonstrates women to constitute a relatively smaller proportion of arthroscopic rotator cuff repair procedures, experience shorter operative time and longer hospital stay, and face greater risk of early postoperative minor adverse events, whereas male patients are at greater risk for severe adverse events and readmission following surgery. By highlighting sex-related disparities in rotator cuff repair, this study indicates the need for further research to understand and address the root causes of inequality and optimize orthopedic care for all.
Acknowledgments
The authors would like to express their gratitude to Yanzhi Wang, PhD, from the University of Illinois College of Medicine Research Services for her assistance with statistical analyses.
Disclaimers
Funding: This study was supported by the Conine Family Fund for Joint Preservation.
Conflicts of interest: The authors, their immediate families, and any research foundation with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.
Footnotes
This study was approved by Mass General Brigham IRB Protocol #2021P001230, “Analyzing Sports Medicine Treatment Outcomes in NSQIP Data”.
References
- 1.Amen T.B., Varady N.H., Rajaee S., Chen A.F. Persistent racial disparities in utilization rates and perioperative metrics in total joint arthroplasty in the U.S.: a comprehensive analysis of trends from 2006 to 2015. J Bone Joint Surg Am. 2020;102:811–820. doi: 10.2106/JBJS.19.01194. [DOI] [PubMed] [Google Scholar]
- 2.Amen T.B., Varady N.H., Shannon E.M., Chopra A., Rajaee S., Chen A.F. Racial and ethnic disparities in hip fracture surgery care in the United States from 2006 to 2015: a nationwide trends study. J Am Acad Orthop Surg. 2021;30:e182–e190. doi: 10.5435/jaaos-d-21-00137. [DOI] [PubMed] [Google Scholar]
- 3.Armitage P. Tests for linear trends in proportions and frequencies. Biometrics. 1955;11:375–386. [Google Scholar]
- 4.Basques B.A., Hijji F.Y., Khechen B., Haws B.E., Mayo B.C., Massel D.H., et al. Sex differences for anterior cervical fusion: complications and length of stay. Spine (Phila Pa 1976) 2018;43:1025–1030. doi: 10.1097/BRS.0000000000002512. [DOI] [PubMed] [Google Scholar]
- 5.Beasley L., Faryniarz D.A., Hannafin J.A. Multidirectional instability of the shoulder in the female athlete. Clin Sports Med. 2000;19:331–349. doi: 10.1016/s0278-5919(05)70207-6. x. [DOI] [PubMed] [Google Scholar]
- 6.Berthelot P., Carricajo A., Aubert G., Akhavan H., Gazielly D., Lucht F. Outbreak of postoperative shoulder arthritis due to Propionibacterium acnes infection in nondebilitated patients. Infect Control Hosp Epidemiol. 2006;27:987–990. doi: 10.1086/507287. [DOI] [PubMed] [Google Scholar]
- 7.Bohl D.D., Basques B.A., Golinvaux N.S., Miller C.P., Baumgaertner M.R., Grauer J.N. Extramedullary compared with intramedullary implants for intertrochanteric hip fractures: thirty-day outcomes of 4432 procedures from the ACS NSQIP database. J Bone Joint Surg Am. 2014;96:1871–1877. doi: 10.2106/jbjs.N.00041. [DOI] [PubMed] [Google Scholar]
- 8.Bohl D.D., Russo G.S., Basques B.A., Golinvaux N.S., Fu M.C., Long W.D., 3rd, et al. Variations in data collection methods between national databases affect study results: a comparison of the nationwide inpatient sample and national surgical quality improvement program databases for lumbar spine fusion procedures. J Bone Joint Surg Am. 2014;96 doi: 10.2106/JBJS.M.01490. [DOI] [PubMed] [Google Scholar]
- 9.Bohl D.D., Singh K., Grauer J.N. Nationwide databases in orthopaedic surgery research. J Am Acad Orthop Surg. 2016;24:673–682. doi: 10.5435/JAAOS-D-15-00217. [DOI] [PubMed] [Google Scholar]
- 10.Bovonratwet P., Ondeck N.T., Nelson S.J., Cui J.J., Webb M.L., Grauer J.N. Comparison of outpatient vs inpatient total knee arthroplasty: an ACS-NSQIP analysis. J Arthroplasty. 2017;32:1773–1778. doi: 10.1016/j.arth.2017.01.043. [DOI] [PubMed] [Google Scholar]
- 11.Cochran W.M. Some methods for strengthening the common χ2 tests. Biometrics. 1954;10:35. [Google Scholar]
- 12.Cody E.A., Strickland S.M. Multidirectional instability in the female athlete. Oper Tech Sports Med. 2014;22:34–43. doi: 10.1053/j.otsm.2014.02.003. [DOI] [Google Scholar]
- 13.Daniels S.D., Stewart C.M., Garvey K.D., Brook E.M., Higgins L.D., Matzkin E.G. Sex-based differences in patient-reported outcomes after arthroscopic rotator cuff repair. Orthop J Sports Med. 2019;7 doi: 10.1177/2325967119881959. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Day M.A., Westermann R.W., Bedard N.A., Glass N.A., Wolf B.R. Trends associated with open versus arthroscopic rotator cuff repair. HSS J. 2019;15:133–136. doi: 10.1007/s11420-018-9628-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 15.Eberlin C.T., Varady N.H., Kucharik M.P., Naessig S.A., Best M.J., Martin S.D. Comparison of perioperative complications following surgical treatment of shoulder instability. JSES Int. 2022;6:355–361. doi: 10.1016/j.jseint.2022.01.001. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Ensor K.L., Kwon Y.W., Dibeneditto M.R., Zuckerman J.D., Rokito A.S. The rising incidence of rotator cuff repairs. J Shoulder Elbow Surg. 2013;22:1628–1632. doi: 10.1016/j.jse.2013.01.006. [DOI] [PubMed] [Google Scholar]
- 17.Figueiredo E.A., Loyola L.C., Belangero P.S., Campos Ribeiro-Dos-Santos A.K., Emanuel Batista Santos S., Cohen C., et al. Rotator cuff tear susceptibility is associated with variants in genes involved in tendon extracellular matrix homeostasis. J Orthop Res. 2020;38:192–201. doi: 10.1002/jor.24455. [DOI] [PubMed] [Google Scholar]
- 18.Fox H.M., Best M.J., Mikula J.D., Aziz K.T., Srikumaran U. Short-term complications and readmission following total shoulder arthroplasty: a National Database Study. Arch Bone Jt Surg. 2021;9:323–329. doi: 10.22038/abjs.2020.48852.2426. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.Gartsman G.M., Brinker M.R., Khan M. Early effectiveness of arthroscopic repair for full-thickness tears of the rotator cuff: an outcome analysis. J Bone Joint Surg Am. 1998;80:33–40. [PubMed] [Google Scholar]
- 20.Gartsman G.M., Khan M., Hammerman S.M. Arthroscopic repair of full-thickness tears of the rotator cuff. J Bone Joint Surg Am. 1998;80:832–840. doi: 10.2106/00004623-199806000-00007. [DOI] [PubMed] [Google Scholar]
- 21.Gianakos A.L., George N., Pinninti A., Kwan S., LaPorte D., Mulcahey M.K. Sex- and gender-specific analysis in orthopaedic studies. Clin Orthop Relat Res. 2020;478:1482–1488. doi: 10.1097/CORR.0000000000001172. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22.Harris A.B., Best M.J., Weiner S., Gupta H.O., Jenkins S.G., Srikumaran U. Hospital readmission rates following outpatient versus inpatient shoulder arthroplasty. Orthopedics. 2021;44:e173–e177. doi: 10.3928/01477447-20200925-03. [DOI] [PubMed] [Google Scholar]
- 23.Hart D.A., Frank C.B., Kydd A., Ivie T., Sciore P., Reno C. In: Maffulli N., Renström P., Leadbetter W.B., editors. Springer London; London: 2005. Neurogenic, mast cell, and gender variables in tendon biology: potential role in chronic tendinopathy. (Tendon Injuries: Basic Science and Clinical Medicine). 40-48. ISBN: 978-1-84628-050-4. [Google Scholar]
- 24.Khuri S.F. The NSQIP: a new frontier in surgery. Surgery. 2005;138:837–843. doi: 10.1016/j.surg.2005.08.016. [DOI] [PubMed] [Google Scholar]
- 25.Knapp B.M., Botros M., Sing D.C., Curry E.J., Eichinger J.K., Li X. Sex differences in complications and readmission rates following shoulder arthroplasty in the United States. JSES Int. 2020;4:95–99. doi: 10.1016/j.jseint.2019.11.007. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26.Kucharik M.P., Varady N.H., Best M.J., Rudisill S.S., Naessig S.A., Eberlin C.T., et al. Comparison of outpatient vs. inpatient anatomic total shoulder arthroplasty: a propensity score-matched analysis of 20,035 procedures. JSES Int. 2022;6:15–20. doi: 10.1016/j.jseint.2021.09.015. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 27.Lan R.H., Samuel L.T., Grits D., Kamath A.F. Contemporary outpatient arthroplasty is safe compared with inpatient surgery: a propensity score-matched analysis of 574,375 procedures. J Bone Joint Surg Am. 2021;103:593–600. doi: 10.2106/JBJS.20.01307. [DOI] [PubMed] [Google Scholar]
- 28.Larson A.N. CORR insights(R): sex- and gender-specific analysis in orthopaedic studies. Clin Orthop Relat Res. 2020;478:1489–1490. doi: 10.1097/CORR.0000000000001304. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 29.Leroux T.S., Basques B.A., Frank R.M., Griffin J.W., Nicholson G.P., Cole B.J., et al. Outpatient total shoulder arthroplasty: a population-based study comparing adverse event and readmission rates to inpatient total shoulder arthroplasty. J Shoulder Elbow Surg. 2016;25:1780–1786. doi: 10.1016/j.jse.2016.04.006. [DOI] [PubMed] [Google Scholar]
- 30.MacDermid J.C., Bryant D., Holtby R., Razmjou H., Faber K., Canada J., et al. Arthroscopic versus mini-open rotator cuff repair: a randomized trial and meta-analysis. Am J Sports Med. 2021;49:3184–3195. doi: 10.1177/03635465211038233. [DOI] [PubMed] [Google Scholar]
- 31.Magnuson J.A., Wolf B.R., Cronin K.J., Jacobs C.A., Ortiz S.F., Bishop J.Y., et al. Sex-related differences in patients undergoing surgery for shoulder instability: a Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability cohort study. J Shoulder Elbow Surg. 2019;28:1013–1021. doi: 10.1016/j.jse.2019.02.020. [DOI] [PubMed] [Google Scholar]
- 32.Maier SPR S.S., Wright C.L., Daniell H.D., Lydston M., O’Donnell E.A. Sex differences in shoulder anatomy and biomechanics: a systematic review and meta-analysis. J Women’s Sports Med. 2022;2:5–17. doi: 10.53646/jwsm.v2i1.19. [DOI] [Google Scholar]
- 33.Manfrini O., Yoon J., van der Schaar M., Kedev S., Vavlukis M., Stankovic G., et al. Sex differences in modifiable risk factors and severity of coronary artery disease. J Am Heart Assoc. 2020;9 doi: 10.1161/JAHA.120.017235. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 34.Manoharan S.R., Baker D.K., Pasara S.M., Ponce B., Deinlein D., Theiss S.M. Thirty-day readmissions following adult spinal deformity surgery: an analysis of the National Surgical Quality Improvement Program (NSQIP) database. Spine J. 2016;16:862–866. doi: 10.1016/j.spinee.2016.03.014. [DOI] [PubMed] [Google Scholar]
- 35.Mantilla C.B., Horlocker T.T., Schroeder D.R., Berry D.J., Brown D.L. Frequency of myocardial infarction, pulmonary embolism, deep venous thrombosis, and death following primary hip or knee arthroplasty. Anesthesiology. 2002;96:1140–1146. doi: 10.1097/00000542-200205000-00017. [DOI] [PubMed] [Google Scholar]
- 36.Molina C.S., Thakore R.V., Blumer A., Obremskey W.T., Sethi M.K. Use of the national surgical quality improvement program in orthopaedic surgery. Clin Orthop Relat Res. 2015;473:1574–1581. doi: 10.1007/s11999-014-3597-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 37.Moosmayer S., Smith H.J., Tariq R., Larmo A. Prevalence and characteristics of asymptomatic tears of the rotator cuff: an ultrasonographic and clinical study. J Bone Joint Surg Br. 2009;91:196–200. doi: 10.1302/0301-620X.91B2.21069. [DOI] [PubMed] [Google Scholar]
- 38.Nandi M., Schreiber K.L., Martel M.O., Cornelius M., Campbell C.M., Haythornthwaite J.A., et al. Sex differences in negative affect and postoperative pain in patients undergoing total knee arthroplasty. Biol Sex Differ. 2019;10:23. doi: 10.1186/s13293-019-0237-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 39.Razmjou H., Holtby R., Myhr T. Gender differences in quality of life and extent of rotator cuff pathology. Arthroscopy. 2006;22:57–62. doi: 10.1016/j.arthro.2005.10.014. [DOI] [PubMed] [Google Scholar]
- 40.Rhon D.I., Snodgrass S.J., Cleland J.A., Sissel C.D., Cook C.E. Predictors of chronic prescription opioid use after orthopedic surgery: derivation of a clinical prediction rule. Perioper Med (Lond) 2018;7:25. doi: 10.1186/s13741-018-0105-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 41.Sabo M.T., LeBlanc J., Hildebrand K.A. Patient gender and rotator cuff surgery: are there differences in outcome? BMC Musculoskelet Disord. 2021;22:838. doi: 10.1186/s12891-021-04701-y. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 42.Saltzman B.M., Basques B., Leroux T., Frank R.M., Nicholson G.P., Verma N.N., et al. The influence of gender on early adverse events, hospital charges and length of stay after shoulder arthroplasty. Int Orthop. 2018;42:149–155. doi: 10.1007/s00264-017-3547-6. [DOI] [PubMed] [Google Scholar]
- 43.Salvo J.P., Nho S.J., Wolff A.B., Christoforetti J.J., Van Thiel G.S., Ellis T.J., et al. Sex-dependent differences in preoperative, radiographic, and intraoperative characteristics of patients undergoing hip arthroscopy: results from the multicenter arthroscopic study of the hip group. Arthroscopy. 2018;34:844–852. doi: 10.1016/j.arthro.2017.09.044. [DOI] [PubMed] [Google Scholar]
- 44.Santaguida P.L., Hawker G.A., Hudak P.L., Glazier R., Mahomed N.N., Kreder H.J., et al. Patient characteristics affecting the prognosis of total hip and knee joint arthroplasty: a systematic review. Can J Surg. 2008;51:428–436. [PMC free article] [PubMed] [Google Scholar]
- 45.Schilling P.L., Hallstrom B.R., Birkmeyer J.D., Carpenter J.E. Prioritizing perioperative quality improvement in orthopaedic surgery. J Bone Joint Surg Am. 2010;92:1884–1889. doi: 10.2106/JBJS.I.00735. [DOI] [PubMed] [Google Scholar]
- 46.Shiloach M., Frencher S.K., Jr., Steeger J.E., Rowell K.S., Bartzokis K., Tomeh M.G., et al. Toward robust information: data quality and inter-rater reliability in the American College of Surgeons National Surgical Quality Improvement Program. J Am Coll Surg. 2010;210:6–16. doi: 10.1016/j.jamcollsurg.2009.09.031. [DOI] [PubMed] [Google Scholar]
- 47.Siccoli A., Staartjes V.E., de Wispelaere M.P., Schroder M.L. Gender differences in degenerative spine surgery: do female patients really fare worse? Eur Spine J. 2018;27:2427–2435. doi: 10.1007/s00586-018-5737-3. [DOI] [PubMed] [Google Scholar]
- 48.Stollsteimer G.T., Savoie F.H., 3rd Arthroscopic rotator cuff repair: current indications, limitations, techniques, and results. Instr Course Lect. 1998;47:59–65. [PubMed] [Google Scholar]
- 49.Tauro J.C. Arthroscopic rotator cuff repair: analysis of technique and results at 2- and 3-year follow-up. Arthroscopy. 1998;14:45–51. doi: 10.1016/s0749-8063(98)70119-7. [DOI] [PubMed] [Google Scholar]
- 50.Wylie J.D., Suter T., Potter M.Q., Granger E.K., Tashjian R.Z. Mental health has a stronger association with patient-reported shoulder pain and function than tear size in patients with full-thickness rotator cuff tears. J Bone Joint Surg Am. 2016;98:251–256. doi: 10.2106/JBJS.O.00444. [DOI] [PubMed] [Google Scholar]