1 Introduction

As its indications have expanded over recent years, hip arthroscopy has increased in prevalence and emerged as a primary treatment option for several pathologies of the hip.^1–3 Femoroacetabular impingement (FAI) syndrome is one such condition that can cause significant hip pain and dysfunction and has been linked to the development of hip osteoarthritis.^4,5 Arthroscopic intervention for pathologies such as FAI has several advantages, including low complication and reoperation rates, expedited rehabilitation, high return to sport rates, and favorable patient-reported outcomes (PROs).^6,7 Consequently, the utilization of hip arthroscopy has increased as a preferred treatment modality over traditional open techniques for select pathologies.^6–8 As a result, there is a growing need to optimize outcomes, particularly PROs, after hip arthroscopy. With increasing evidence that less easily modifiable factors such as mental health negatively impact outcomes after hip arthroscopy, identifying potential areas for surgeon-driven interventions to improve outcomes after hip arthroscopy is particularly of interest.^9–13

Preoperative patient expectations have been identified as an important determinant of PROs within several orthopaedic subspecialites.^14–21 However, this relationship remains understudied in the context of patients undergoing hip arthroscopy. The results from previous studies of preoperative expectations in patients undergoing hip arthroscopy have been mixed. Most studies in hip arthroscopy patients have found no association between preoperative expectations and satisfaction; however, one study found a significant association between higher preoperative expectations and improvements in the modified Harris Hip Score (mHHS) and Hip Outcomes Score-Activities of Daily Living Subscale (HOS-ADL) at 1 year postoperatively.^22,23 Further studies are needed to better establish the relationship between preoperative expectations and PROs for patients undergoing hip arthroscopy for FAI and other indications.

The purpose of this study was to explore the relationship between preoperative patient expectations and PROs in patients undergoing hip arthroscopy. Specific aims were to determine the preoperative factors associated with patient expectations, as well as to determine the relationship between preoperative expectations and PROs at 2 years postoperatively. We hypothesized that higher preoperative patient expectations would predict better PROs 2 years after hip arthroscopy.

2 Methods

After Institutional Review Board (IRB) approval, a prospectively maintained registry at a single academic institution was queried retrospectively for all patients who underwent hip arthroscopy from October 2015 to October 2021.²⁴ Procedures for labral tear and/or FAI syndrome were included for analysis, which included arthroscopic femoroplasty (69 %), labral repair (65 %), and chondroplasty, abrasion arthroplasty, and/or labral resection (27 %). All procedures were performed by one of three board-certified, sports-fellowship trained surgeons. All surgeons adhered to similar postoperative rehabilitation protocols. Informed consent was obtained from each patient prior to enrollment in the registry.

PROs were obtained via electronic survey at baseline and 2 years postoperatively. A minimum of 3 reminders were sent to each patient via email, text, and/or phone call. Patients who failed to respond to the follow-up survey by 3 years postoperatively were considered lost to follow-up. PRO measures included 6 Patient-Reported Outcomes Measurement Information System (PROMIS)²⁵ computer adaptive test (CAT) domains – Physical Function (PF), Pain Interference (PI), Fatigue, Social Satisfaction (SS), Anxiety, and Depression. Surveys assessed pain and activity by using the numeric pain scale (NPS)²⁶ and the Marx activity rating scale (MARS) for the lower extremity.²⁷ Surveys also allowed patients to self-report sociodemographic data. The electronic medical record was used to supplement surveys and complete relevant demographic data. Comorbidities and preoperative health status, including body mass index (BMI), were also gathered from the electronic medical record. All study data were collected and managed using REDCap electronic data capture tools hosted at the study institution.^28,29

Preoperative patient expectations were measured using the expectations domain of the Musculoskeletal Outcomes Data Evaluation and Management System (MODEMS),^30,31 which is a low burden instrument that has been validated in an orthopaedic population. Preoperatively, MODEMS assesses a patient's expected results of treatment in 6 key areas: relief from symptoms, doing household activities, sleeping more comfortably, returning to work, exercising and recreation, and preventing disability. Each item is measured on a 5-point Likert scale, with responses ranging from “not at all likely” to “extremely likely”. Missing items or items marked “not applicable” are not scored. The average score across all items was calculated and converted to a scale from 0 to 100, with a higher score representing higher levels of preoperative expectations.

Continuous variables were reported as mean and standard deviation, and categorical variables were reported as frequency and percentage. Preoperative patient expectation scores were not normally distributed; therefore, nonparametric testing with Wilcoxon Rank-Sum and Kruskal-Wallis tests was performed to compare mean preoperative patient expectations between categorical variables with 2 groups, or more than 2 groups, respectively. Spearman's rank correlation coefficient was used to assess the relationship between preoperative patient expectations and continuous variables. Additionally, patient expectations were compared between patients who completed the 2-year follow-up survey and those who did not. Preoperative patient expectations were also compared between those that achieved a minimal clinically important difference (MCID) in each PRO 2 years postoperatively and those that did not. Published anchor-based values in comparative populations were used where possible. These values were 5.1 and 10.9 for the PROMIS PF and PI domains, respectively,³² 1.5 for NPS,³³ and 12.5 for MARS.³⁴ MCID for PROMIS Fatigue, SS, Anxiety, and Depression was calculated as one-half the standard deviation of these PROs baseline distribution. Lastly, linear regression models were created using standard least squares to identify the effect of preoperative expectations on 2-year outcomes when controlling for possible confounding variables. A priori variables included age, sex, smoking status, prior ipsilateral hip surgery, and preoperative patient expectations. BMI and baseline MARS for the lower extremity were also included based on the results of the bivariate analysis. Non-significant variables were removed from the initial models in backwards fashion until only significant variables remained. All statistical tests were 2-tailed with an alpha level of 0.05. Analyses were performed using JMP Pro, Version 17 software (JMP®, Version 17.0.0. SAS Institute Inc., Cary, NC, 1989–2023).

3 Results

A total of 117 patients were enrolled in the registry. Of the initial 117 patients, 12 patients did not complete the baseline expectations survey. There were 27 patients lost to follow up, leading to a final cohort of 78 patients (74 %). The median time to follow up was 25 months (Range 24–32 months). Patients overall had high preoperative expectations of hip arthroscopy (Table 1). The majority of patients for each expectations question answered, “Extremely likely.” Patients had the highest expectations for exercising and recreation (76 % answering “Extremely likely”) and the lowest expectations for returning to work and preventing disability (54 % and 55 % respectively answering “Extremely likely”).

Patients were mostly female (72 %) with an average age of 34.3 years (SD = 12.2, Table 2). The majority of patients were white (88 %), college educated (61 %), employed (66 %) with an income >$70,000 (63 %), and had private insurance (84 %). The cohort was overall healthy, as most had never smoked (80 %), were not obese (73 %), and had an American Society of Anesthesiologists (ASA) score of I-II (97 %). A small proportion of patients (14 %) had a history of anxiety or depression, however, there was no statistically significant difference in preoperative expectations based on mental health history. Patients who were obese (BMI ≥30) had statistically significantly lower preoperative expectations (77.2 ± 20.9) compared to patients who were overweight or healthy weight (93.0 ± 10.0 and 91.9 ± 11.5 respectively, p = .004). Otherwise, there were no statistically significant associations between demographic variables and preoperative expectations.

Table 3 demonstrates correlations between preoperative expectations and baseline PROs. Higher preoperative expectations correlated with worse baseline MARS lower extremity scores (rs = −.30, p = .01). There were no other statistically significant correlations between preoperative expectations and baseline PROs. Table 4 reports the correlations between preoperative expectations and postoperative PROs. Higher preoperative expectations correlated with better 2-year scores for PROMIS Fatigue (rs = −.31, p = .01), PROMIS Anxiety (rs = −.32, p = .005), PROMIS Depression (rs = −.25, p = .03), and NPS for the operative hip (rs = −.24, p = .04). Higher preoperative expectations also correlated with better 2-year MARS lower extremity activity scores (rs = .27, p = .02). Additionally, higher preoperative expectations correlated with greater improvement in PROMIS PI (rs = −.24, p = .04), PROMIS Fatigue (−.34, p = .002), NPS for the operative hip (rs = −.25, p = .04), and MARS lower extremity (rs = .44, p < .001) at 2 years compared to baseline.

Table 5 compares the preoperative expectations of patients who did and did not meet MCID for each of the PROs at 2 years postoperatively. Patients who met MCID at 2 years for PROMIS Fatigue were significantly more likely to have higher preoperative expectations compared to those who did not meet MCID (92.6 ± 14.1 vs 82.0 ± 15.8, p = .003). This was also true for MARS lower extremity scores (95.3 ± 8.82 vs 86.2 ± 16.7, p = .014). Meeting MCID for all other PROs trended toward higher preoperative expectations but did not reach statistical significance.

On multivariable linear regression, higher preoperative expectations were a statistically significant independent predictor of better PROMIS Fatigue, SS, and Anxiety at 2 years. Specifically, for every 10-point increase in preoperative expectations there was a predicted 2.6-point improvement in PROMIS Fatigue, 2.4-point improvement in PROMIS SS, and 2.4-point improvement in PROMIS Anxiety (Table 6). Smoking status was also predictive of worse PROMIS Fatigue and Anxiety at 2 years postoperatively. Daily smoking predicted a 13.01-point higher PROMIS Fatigue score and a 10.74-point higher PROMIS Anxiety score at 2 years as compared to no history of smoking. Preoperative expectations did not independently predict PROMIS PF, PROMIS PI, PROMIS Depression, NPS, or MARS lower extremity at 2 years.

4 Discussion

This study found that higher preoperative expectations were an independent predictor of better PROMIS Fatigue, SS, and Anxiety 2 years after hip arthroscopy. Preoperative expectations were not found to independently predict PROMIS PF, PROMIS PI, PROMIS Depression, NPS, or MARS lower extremity at 2 years. To our knowledge, this is the first study to find a significant relationship between MODEMS preoperative expectations and PROMIS psychosocial outcomes 2 years postoperatively in a hip arthroscopy population. Based on our findings, setting positive expectations preoperatively may be an important tool for enhancing psychosocial health for hip arthroscopy patients up to 2 years postoperatively.

The relationship between psychosocial health and baseline function as well as postoperative PROs has been previously reported in patients undergoing hip arthroscopy. Worse baseline mental health status has been found to be associated with worse baseline pain, activity, function, and satisfaction in several studies of patients with FAI syndrome or patients undergoing preoperative evaluation for hip arthroscopy.^9,10,35–38 Poor mental health status has also been linked to worse postoperative PROs, including pain, function, and activity.^9–13 In spite of these results, Saks et al. found that while patients with psychological distress had lower postoperative PROs, they can still have a meaningful clinical benefit from hip arthroscopy for FAI syndrome.¹⁰ The present study found that higher preoperative expectations in patients undergoing hip arthroscopy were an independent predictor of better psychosocial outcomes. Given these findings, establishing positive expectations during the preoperative counseling period could assist with improving psychosocial outcomes, which are known to impact other outcomes such as pain, function, and activity.

Unsurprisingly, daily smoking was predictive of worse PROMIS Fatigue and Anxiety scores at 2 years postoperatively relative to no history of smoking. It is well established in the hip arthroscopy literature that patients who are smoking at the time of surgery have worse postoperative PROs and higher complication rates.^13,39–41 However, Lee et al. demonstrated that patients who quit smoking prior to hip arthroscopy have similar improvements in postoperative PROs compared to their counterparts who have never smoked.⁴² In the present study, quitting smoking was predictive of higher levels of fatigue and anxiety at follow-up relative to no history of smoking; however, the effect size was smaller than daily smoking. Even when controlling for preoperative expectations, patients with any smoking history may experience worse fatigue and anxiety 2 years postoperatively. Interestingly, patients who reported daily smoking also reported high preoperative expectations, suggesting a mismatch in the expectations and outcomes in this subpopulation. These findings demonstrate the importance of smoking cessation counseling and appropriate expectation management prior to hip arthroscopy to aid patients in achieving the best possible outcome.

Chahla et al. investigated the relationship between preoperative expectations and 1-year PROs for patients undergoing hip arthroscopy specifically for FAI syndrome.²² They found that patients with higher preoperative expectations were more likely to achieve clinically significant improvements in 1-year HOS-ADL and mHHS. The present study similarly found a significant relationship between higher preoperative expectations and achieving MCID at 2 years for PROMIS Fatigue and MARS lower extremity scores. Also, the present study still demonstrated this relationship with non-hip specific PROs, which adds to the growing evidence that PROMIS PROs correlate with and are as accurate as hip-specific PROs for patients with FAI.^43–45 More studies are needed to determine whether this relationship continues beyond 2-year follow-up.

In contrast, Factor et al. found no significant relationship between preoperative expectations and iHOT-33 scores or satisfaction at 2 years postoperatively in patients undergoing hip arthroscopy for FAI syndrome.²³ One possible explanation for this difference in findings is that the population in Factor et al. was majority male, while the populations in Chahla et al.²² and the present study were majority female. However, there is growing evidence that gender does not have a significant impact on achieving clinically meaningful improvements in PROs after hip arthroscopy.^46–49 The investigation of different PROs in the current study and previous studies may also explain variability in observed associations with preoperative expectations. Future studies with larger sample sizes and a mix of legacy hip-specific PROs and PROMIS measures could more firmly establish the relationship between preoperative expectations and PROs after hip arthroscopy.

There are several limitations to this study. First, this study used PROs that are not specific to the hip joint, which may be less sensitive than hip-specific PROs in a hip arthroscopy population. However, there is growing evidence that PROMIS outcome scores correlate with and are as accurate as hip-specific PROs for patients with FAI syndrome.^43–45 Second, while MODEMS is a validated and generalizable measure of patient expectations, high overall expectations in this cohort may suggest a ceiling effect that limits the ability to accurately capture the range of expectations. Third, the sample size of this study is relatively small. However, the loss to follow up was only 26 %, which is lower than the national average for arthroscopy registries,⁵⁰ and this sample size compares favorably to the hip arthroscopy literature. Also, this study noted multiple significant relationships between variables confirming an acceptable sample size. Fourth, the patients in this study are from three academic surgeons operating at a single urban center. As a result, these findings may not be generalizable to other patient populations. Despite the above limitations, this study demonstrated a significant relationship between preoperative expectations and psychosocial outcomes 2 years after hip arthroscopy.

5 Conclusion

Higher preoperative expectations were an independent predictor of better PROMIS Fatigue, SS, and Anxiety 2 years after hip arthroscopy. Establishing positive expectations during the preoperative counseling period may be an important tool for enhancing psychosocial health up to 2 years postoperatively for patients undergoing hip arthroscopy.

CRediT authorship contribution statement

Leah E. Henry: Conceptualization, Investigation, Methodology, Writing – original draft, Writing – review & editing. Brandon Leon: Data curation, Writing – original draft, Writing – review & editing. Dominic J. Ventimiglia: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Project administration, Writing – original draft, Writing – review & editing. Michael A. McCurdy: Writing – review & editing. Stefan Dabic: Writing – review & editing. Natalie L. Leong: Investigation, Writing – review & editing. Jonathan D. Packer: Investigation, Writing – review & editing. R. Frank Henn: Investigation, Supervision, Writing – review & editing. Sean J. Meredith: Conceptualization, Investigation, Project administration, Supervision, Writing – review & editing.

Ethics approval

This study was approved by the Institutional Review Board (IRB) Committee at the University of Maryland, Baltimore (HP-00062261).

Consent

Informed consent was obtained from all patients for participation in the study.

Funding

This work was supported by a grant from The James Lawrence Kernan Hospital Endowment Fund, Incorporated (BL1941007WS). This work was also supported in part by Career Development Award Number IK2 BX004879 from the United States (U.S.) Department of Veterans Affairs Biomedical Laboratory R&D (BLRD) Service.