Minimal clinically important difference in the Hip disability and Osteoarthritis Outcome Score (HOOS) for patients undergoing total hip arthroplasty: A multicenter prospective cohort study

Abstract

Background

Total hip arthroplasty (THA) is an effective treatment for hip osteoarthritis (OA), improving pain, function, and quality of life (QOL). The Hip disability and Osteoarthritis Outcome Score (HOOS) is widely used to assess treatment outcomes; however, the minimal clinically important difference (MCID) in the short-term remains unclear. This study aimed to determine MCID values for HOOS at 3 and 6 months post-THA using the anchor method.

Methods

This multicenter prospective cohort study included patients with hip OA undergoing primary unilateral THA. HOOS subscales (symptoms, pain, activities of daily living [ADL], sport and recreation [SR], and QOL) were assessed preoperatively and at 3 and 6 months postoperatively. MCID was determined using receiver operating characteristic analyses with the Global Rating of Change scale as the anchor.

Results

A total of 127 patients were included in the analysis, with 107 patients assessed at 3 months and 102 at 6 months post-THA. At 3 months after THA, the MCID values for the HOOS subscales were 7.50 for symptoms, 8.75 for pain, 4.41 for ADL, 9.38 for SR, and 9.38 for QOL. At 6 months after THA, the corresponding MCID values were 12.50, 11.25, 23.53, 10.00, and 15.63, respectively.

Conclusion

Short-term MCID values for HOOS subscales post-THA were established, aiding early assessment of treatment effectiveness and guiding postoperative care.

Keywords

minimal clinically important difference Hip disability and Osteoarthritis Outcome Score hip osteoarthritis total hip arthroplasty

Introduction

Total hip arthroplasty (THA) is widely performed for individuals with advanced hip disease, especially for those suffering from end-stage hip osteoarthritis (OA), and is known to substantially relieve hip-related symptoms while enabling the restoration of daily function and improvement in overall well-being.¹ Because postoperative recovery trajectories vary, the systematic evaluation of patient outcomes has become increasingly important to inform clinical decision-making. In contemporary practice, treatment benefits are primarily captured using patient-reported outcome measures (PROM), which provide direct insight into how patients perceive changes after THA.² Among these, the Hip disability and Osteoarthritis Outcome Score (HOOS) is a highly reliable, valid, and responsive tool widely applied in clinical settings to evaluate postoperative outcomes.^3–5 HOOS evaluates five subscales—symptoms, pain, activities of daily living (ADL), sport and recreation (SR), and quality of life (QOL)—making it a comprehensive tool to quantify recovery after THA.⁶

Interpreting treatment effects using the minimal clinically important difference (MCID) of HOOS subscales facilitates patient-centered care. Statistical significance does not necessarily imply clinical significance.⁷ MCID represents the smallest change in a measurement that reflects a meaningful improvement following treatment.⁷ A treatment-induced change exceeding the MCID threshold is considered clinically meaningful.⁸ MCID is commonly estimated using anchor-based and distribution-based methods.⁹ Previous studies have reported lower validity for distribution-based MCID values, as they often fall below the minimal detectable change at 80%, 90%, and 95% confidence levels.¹⁰ In contrast, MCID values derived from the anchor-based method effectively distinguish between improved and non-improved patients, demonstrating high area under the curve (AUC) values in receiver operating characteristic (ROC) analysis.¹⁰ Therefore, the anchor-based MCID may provide a more reliable reference for clinical applications.

Although long-term MCID values for HOOS at 1 or 2 years post-THA have been established,^10–12 short-term MCID values at 3 and 6 months remain largely unexplored. Moreover, MCID values for individual HOOS subscales have not been fully elucidated. Establishing short-term MCID values for HOOS would aid early clinical decision-making regarding treatment continuation. Although previously reported MCID values have varied across studies,^10–13 identifying diverse MCID values based on the timing of evaluation, patient demographics, and surgical approaches may help clinicians assess treatment effectiveness more accurately.

This study aimed to determine short-term postoperative MCID values for each HOOS subscale using the anchor method and to evaluate the proportion of patients achieving MCID for each subscale.

Materials and methods

Ethics

This multicenter study received ethical approval through a single institutional review board review process, which covered all participating sites. The study protocol complied with the principles of the Declaration of Helsinki, and only non-invasive assessments required for evaluating functional status were performed. Written informed consent was obtained from all participants prior to enrollment.

Study design

This 6-month follow-up multicenter prospective cohort study determined MCIDs for HOOS subscales at 3 and 6 months post-THA using the anchor method.

Setting

The study was conducted in the rehabilitation department of three facilities. Recruitment, follow-up, and data collection occurred between February 2023 and April 2025.

Participants

Eligible participants were adults diagnosed with hip OA who underwent primary unilateral THA and were able to ambulate independently, either with or without assistive devices, both before and after THA. Individuals were excluded if they had comorbidities or postoperative events likely to affect HOOS scores, including rheumatoid arthritis, systemic lupus erythematosus, cognitive or psychiatric disorders, femoral head necrosis, major complications after THA (such as deep vein thrombosis or periprosthetic fracture), or underwent revision THA.^14–20 Participants with incomplete HOOS data were also excluded from the final dataset.

A unified postoperative rehabilitation protocol was implemented across all facilities. Therapy commenced on postoperative day 1 and comprised progressive lower-limb resistance training, joint range-of-motion exercises, gait training, and targeted muscle strengthening for the hip, knee, and ankle. Following hospital discharge, participants attended outpatient sessions approximately once per week. Supervised rehabilitation was completed within 150 days after THA.

Variables

The primary endpoints were the MCIDs for the HOOS at 3 and 6 months post-THA. The HOOS consists of 40 questions across five subscales: symptoms, pain, ADL, SR, and QOL.³ The HOOS questionnaire includes five questions for symptoms, 10 for pain, 17 for ADL, 4 for SR, and 4 for QOL. Each subscale has five response options, with 0% indicating the worst condition and 100% the best. HOOS is a highly valid, responsive, and reliable PROM for THA.^3,5

Statistical analysis

MCID was calculated using the anchor method, with the Global Rating of Change (GRC) scale as the anchor.²¹ Improvement in each subscale was evaluated using the 11-point GRC scale (−5 to +5), where higher positive values indicated better postoperative recovery. The 11-point GRC scale has high discriminative power.²¹ A change of ≥2 points was considered clinically meaningful.²¹ Patients scoring +2 or more on the GRC scale were classified as the improvement group, whereas those scoring +1 or less were classified as the non-improvement group. ROC curves were constructed using HOOS subscale score changes from preoperative to 3 and 6 months postoperative. MCID was determined using the Youden index.²² The percentage of patients with THA achieving MCID by subscale was also calculated. All statistical analyses were performed using IBM SPSS statistics version 30.0 (IBM Corp., Armonk, NY, USA).

Sample size

Sample size estimation was conducted using MedCalc statistical software version 23.1.7 (MedCalc Software bvba, Ostend, Belgium). The analysis was performed assuming a type I error rate of 0.05, statistical power of 0.80, and a null AUC value of 0.50. The AUC values were interpreted as follows: non-predictive (AUC <0.5), low predictive capacity (0.5≤ AUC <0.7), moderate predictive capacity (0.7≤ AUC <0.9), high predictive capacity (0.9≤ AUC <1), and perfect prediction (AUC = 1).^23,24 Because previous studies investigating MCID after THA have reported AUC values of 0.89–0.93, a conservative expected AUC of 0.80 was selected for the present sample size calculation.²⁵ The allocation ratio for the ROC analysis was informed by published postoperative distributions of improvement and non-improvement groups, setting the proportions at 0.94 and 0.06, respectively.²⁵ Applying these parameters, the minimum total sample size required was estimated to be 101 participants, comprising approximately 94 in the improvement group and 7 in the non-improvement group.

Results

Cohort characteristics

Of the 127 eligible patients, 107 were followed up at 3 months. At 6 months, 102 remained, whereas five were lost to follow-up (Figure 1). Baseline characteristics and HOOS data before and after THA are shown in Tables 1 and 2, respectively.

Figure 1.

Study flow diagram. HOOS, Hip disability and Osteoarthritis Outcome Score; THA, total hip arthroplasty.

Table 1.

Baseline patient characteristics.

Variables	THA study cohort (n = 127)
Age, years	69.26 ± 9.41
Female, n (%)	116 (91.34)
BMI (kg/m²)	25.10 ± 4.41
WHO classification of obesity, n (%)
Underweight	7 (5.51)
Normal weight	60 (47.24)
Pre-obese	44 (34.65)
Obese class I	13 (10.24)
Obese class II	2 (1.57)
Obese class III	1 (0.79)
ASA, n (%)
1	9 (7.09)
2	99 (77.95)
3	18 (14.17)
4	1 (0.79)
CCI, n (%)
0	113 (88.98)
1-2	14 (11.02)
≥3	0 (0)
Surgical approach, n (%)
Anterolateral approach	110 (86.61)
Direct lateral approach	4 (3.15)
Posterolateral approach	13 (10.24)

Values are presented as mean ± standard deviation.

ASA, American Society of Anesthesiologists physical status classification; BMI, body mass index; CCI, Charlson comorbidity index; THA, total hip arthroplasty; WHO, World Health Organization.

Table 2.

HOOS subscale scores pre-THA and at 3 and 6 months post-THA.

HOOS	Pre-THA	3 months post-THA	6 months post-THA
Symptoms	37.40 ± 21.00	69.63 ± 20.77	76.35 ± 19.24
Pain	43.78 ± 19.49	78.69 ± 19.58	86.03 ± 16.58
ADL	39.35 ± 19.95	73.06 ± 17.96	80.95 ± 16.41
SR	18.54 ± 20.07	44.98 ± 26.90	53.61 ± 27.85
QOL	23.72 ± 15.09	58.12 ± 22.85	66.18 ± 21.26

Values are presented as mean ± standard deviation.

ADL, activities of daily living; HOOS, Hip disability and Osteoarthritis Outcome Score; QOL, quality of life; SR, sport and recreation; THA, total hip arthroplasty.

Minimally clinically important difference

At 3 months post-THA, the HOOS MCIDs were 7.50 (symptoms), 8.75 (pain), 4.41 (ADL), 9.38 (SR), and 9.38 (QOL) (Table 3). At 6 months, the MCIDs were 12.50 (symptoms), 11.25 (pain), 23.53 (ADL), 10.00 (SR), and 15.63 (QOL) (Table 4). The diagnostic accuracy of MCID at 3 months postoperatively was excellent for pain (AUC 0.99), ADL (AUC 0.91), and QOL (AUC 0.94), good for symptoms (AUC 0.87), and fair for SR (AUC 0.77) (Table 3). At 6 months, accuracy was excellent for symptoms (AUC 0.97), pain (AUC 0.98), and QOL (AUC 0.98), good for ADL (AUC 0.86), and fair for SR (AUC 0.78) (Table 4). MCID achievement rates ranged from 68.22% to 92.52% at 3 months and 76.47% to 90.20% at 6 months (Tables 3 and 4). For all subscales, both MCID values and achievement rates were higher at 6 months postoperatively than at 3 months postoperatively.

Table 3.

MCID thresholds for HOOS at 3 months post-THA.

HOOS	MCID	Sensitivity	Specificity	AUC (95%CI)	p value	Percent achieving
Symptoms	7.50	0.87	0.80	0.87 (0.77–0.96)	<0.001	80.38
Pain	8.75	0.97	1.00	0.99 (0.97–1.00)	<0.001	89.72
ADL	4.41	0.97	0.75	0.91 (0.80–1.00)	<0.001	92.52
SR	9.38	0.82	0.62	0.77 (0.67–0.86)	<0.001	68.22
QOL	9.38	0.91	0.89	0.94 (0.85–1.00)	<0.001	84.11

ADL, activities of daily living; AUC, area under the curve; CI, confidence interval; HOOS, Hip disability and Osteoarthritis Outcome Score; MCID, minimal clinically important difference; QOL, quality of life; SR, sport and recreation; THA, total hip arthroplasty.

Table 4.

MCID thresholds for HOOS at 6 months post-THA.

HOOS	MCID	Sensitivity	Specificity	AUC (95%CI)	p value	Percent achieving
Symptoms	12.50	0.90	1.00	0.97 (0.94–1.00)	<0.001	83.33
Pain	11.25	0.95	1.00	0.98 (0.95–1.00)	<0.001	90.20
ADL	23.53	0.77	0.80	0.86 (0.69–1.00)	<0.001	77.45
SR	10.00	0.83	0.80	0.78 (0.61–0.95)	0.001	76.47
QOL	15.63	0.92	1.00	0.98 (0.96–1.00)	<0.001	86.27

Discussion

This study determined the MCID of HOOS subscales at 3 and 6 months post-THA, with AUC values of at least 0.77 for all subscales, confirming statistical significance. These findings support the validity of MCID as a measure for assessing postoperative improvements across subscales.

This study is the first to calculate MCID for HOOS subscales at 3 and 6 months post-THA. In previous studies, all MCIDs calculated by HOOS subscale were after 1 year post-THA.^10–12 Compared to prior findings—symptoms (17.0), pain (27.5), ADL (19.1), SR (16.7), and QOL (6.0)¹²—the MCID values observed at 3 months in this study were lower for all subscales except for QOL. At 6 months, the MCIDs for ADL and QOL exceeded the prior 1-year estimate, while the MCIDs for symptoms, pain, and SR remained lower. This difference may be attributed to the progressive improvement in physical function over time following THA.^26,27 Additionally, the higher MCID values for ADL and QOL at 6 months post-THA in this study may reflect differences in patient demographics and treatment methods.

A notable finding of this study was the marked increase in the MCID threshold for the ADL subscale from 3 months (4.41) to 6 months (23.53) post-THA. Although this change may appear substantial, it should be interpreted in the context of the anchor-based MCID methodology. MCID is not a fixed biological constant but is rather a time-dependent construct that reflects patients’ perception of meaningful change relative to their recovery stage. At 3 months post-THA, many patients experienced rapid functional gains, and even small improvements in basic daily activities may be perceived as clinically meaningful. In contrast, by 6 months, functional recovery has progressed substantially, and patients have often recalibrated their internal standards, requiring larger absolute improvements in ADL scores to perceive further change as meaningful. This shift results in a higher MCID threshold despite continued clinical improvement, rather than indicating instability of the measurement itself. Importantly, the diagnostic performance of the ADL MCID at 6 months remained good (AUC = 0.86), supporting the interpretability of this threshold despite its higher absolute value.

The SR subscale demonstrated the lowest MCID achievement rates at both 3 and 6 months compared with the other subscales. This is consistent with the predominantly older study population, for whom high-level activities are less likely to be regained early after THA. Although HOOS was originally designed to accommodate a wide range of functional expectations—including younger or more active patients—older adults may face slower or more heterogeneous recovery patterns in sport-related tasks.²⁸ For older adults seeking to return to SR, individualized interventions may be necessary alongside standard rehabilitation. Furthermore, the AUC for MCID in SR remained below 0.8, warranting caution when interpreting treatment effectiveness.²⁹

The primary strength of this study was the first calculation of MCID by HOOS subscales in the short-term after THA for hip OA. The ability to clarify treatment effects earlier would be beneficial to both clinicians and patients, contributing significantly to patient-centered care. Nevertheless, this study has several limitations. First, the sample size in this study was not sufficient for generalization. Although the study size allowed validation of moderate predictive value, the findings may not have represented the entire population of patients undergoing THA worldwide. In particular, more than 90% of the cohort consisted of female patients. This sex distribution may reflect the epidemiology of hip OA in Japan, where acetabular dysplasia—more common in female—frequently contributes to the development of secondary hip OA and subsequent THA.³⁰ However, the underlying etiology of hip OA (primary age-related vs secondary dysplasia-related) was not systematically assessed in this study. Therefore, it was not possible to stratify MCID values according to disease etiology, and the derived thresholds likely represent aggregated estimates across a heterogeneous hip OA population. Given that both sex and disease etiology may influence postoperative recovery trajectories and patient-reported outcome responses, this imbalance may limit the external validity of the MCID estimates, particularly when applied to male patients or to populations wherein primary OA predominates.³¹ Future studies with larger and more demographically balanced cohorts are needed to establish etiology-specific MCID thresholds and to enhance the generalizability of these findings across diverse patient populations. Second, SR subscale demonstrated only fair discriminative ability at both 3 and 6 months postoperatively (AUC <0.8). This finding is likely attributable to the advanced age of the study cohort and limited engagement in high-demand activities during the early postoperative period. In older patients undergoing THA, the recovery of SR-related functions is often delayed or heterogeneous, which may reduce the ability of short-term score changes to discriminate between clinically meaningful and non-meaningful improvement. Third, adjustments for factors influencing HOOS results, such as socioeconomic determinants and physical activity, remained inadequate. A lower educational level has been associated with worse pain and physical function,³² and inactive patients undergoing THA experience greater improvements in physical activity levels than those who were active before surgery.³³ Future studies should adjust for these factors. Finally, differences in THA techniques and their impact on MCID could not be examined. Variations in functional recovery speed and pain relief may exist across surgical techniques, warranting further investigation.^34,35

Conclusion

In this study, we calculated MCID by HOOS subscales at 3 and 6 months postoperatively for patients undergoing primary unilateral THA for hip OA. These findings may be useful in evaluating the effectiveness of various interventions and treatments for patients who have undergone THA.

Footnotes

ORCID iD

Junji Nishimoto

Funding

The authors received no financial support for the research, authorship, and publication of this article.

Declaration of conflicting interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.*

References

Snell

Dunn

Hooper

. Associations between pain, function and quality of life after total hip arthroplasty. Int J Orthop Trauma Nurs 2024; 54: 101121. https://doi.org/10.1016/j.ijotn.2024.101121

Lan

Bell

Samuel

, et al.

Outcome measures in Total hip arthroplasty: have our metrics changed over 15 years?

Arch Orthop Trauma Surg 2022; 142: 1753–1762. https://doi.org/10.1007/s00402-021-03809-z

Nilsdotter

Lohmander

Klässbo

, et al. Hip disability and osteoarthritis outcome score (HOOS) – validity and responsiveness in total hip replacement. BMC Musculoskelet Disord 2003; 4: 10. https://doi.org/10.1186/1471-2474-4-10

Thorborg

Roos

Bartels

, et al. Validity, reliability and responsiveness of patient-reported outcome questionnaires when assessing hip and groin disability: a systematic review. Br J Sports Med 2010; 44: 1186–1196. https://doi.org/10.1136/bjsm.2009.060889

Satoh

Masuhara

Goldhahn

, et al. Cross-cultural adaptation and validation reliability, validity of the Japanese version of the Hip disability and Osteoarthritis Outcome Score (HOOS) in patients with hip osteoarthritis. Osteoarthr Cartil 2013; 21: 570–573. https://doi.org/10.1016/j.joca.2013.01.015

Paulsen

. Patient reported outcomes in hip arthroplasty registries. Dan Med J 2014; 61: B4845.

Bloom

Kaplan

Mojica

, et al. The minimal clinically important difference: a review of clinical significance. Am J Sports Med 2023; 51: 520–524. https://doi.org/10.1177/03635465211053869

Beaton

Boers

Wells

. Many faces of the minimal clinically important difference (MCID): a literature review and directions for future research. Curr Opin Rheumatol 2002; 14: 109–114. https://doi.org/10.1097/00002281-200203000-00006

Engel

Beaton

Touma

. Minimal clinically important difference: a review of outcome measure score interpretation. Rheum Dis Clin North Am 2018; 44: 177–188. https://doi.org/10.1016/j.rdc.2018.01.011

10.

Lyman

Lee

McLawhorn

, et al.

What are the minimal and substantial improvements in the HOOS and KOOS and JR versions after total joint replacement?

Clin Orthop Relat Res 2018; 476: 2432–2441. https://doi.org/10.1097/CORR.0000000000000456

11.

Kemp

Collins

Roos

, et al. Psychometric properties of patient-reported outcome measures for hip arthroscopic surgery. Am J Sports Med 2013; 41: 2065–2073. https://doi.org/10.1177/0363546513494173

12.

Kuo

Giori

Bowe

, et al. Comparing methods to determine the minimal clinically important differences in patient-reported outcome measures for veterans undergoing elective total hip or knee arthroplasty in veterans health administration hospitals. JAMA Surg 2020; 155: 404–411. https://doi.org/10.1001/jamasurg.2020.0024

13.

Guy

Albright

Only

, et al. Interpreting the Hip osteoarthritis outcome score joint replacement: minimum clinically important difference values vary over time within the same patient population. J Orthop Exp Innov 2022; 2.

14.

Imagama

Tokushige

Seki

, et al. Risk factors associated with short-term clinical results after total hip arthroplasty for patients with rheumatoid arthritis. Orthopedics 2018; 41: e772–e776. https://doi.org/10.3928/01477447-20180828-06

15.

Roberts

Mandl

, et al. Patients with systemic lupus erythematosus have increased risk of short-term adverse events after total hip arthroplasty. J Rheumatol 2016; 43: 1498–1502. https://doi.org/10.3899/jrheum.151373

16.

Viramontes

Luan Erfe

Erfe

, et al. Cognitive impairment and postoperative outcomes in patients undergoing primary total hip arthroplasty: a systematic review. J Clin Anesth 2019; 56: 65–76. https://doi.org/10.1016/j.jclinane.2019.01.024

17.

Park

Zhong

Miley

, et al. Preoperatively predicting failure to achieve the minimum clinically important difference and the substantial clinical benefit in patient-reported outcome measures for total hip arthroplasty patients using machine learning. BMC Musculoskelet Disord 2025; 26: 150. https://doi.org/10.1186/s12891-025-08339-y

18.

Harada

Hamai

Shiomoto

, et al. Patient-reported outcomes after primary or revision total hip arthroplasty: a propensity score-matched Asian cohort study. PLoS One 2021; 16: e0252112. https://doi.org/10.1371/journal.pone.0252112

19.

Dua

Desai

Lee

, et al. National trends in deep vein thrombosis following total knee and total hip replacement in the United States. Ann Vasc Surg 2017; 38: 310–314. https://doi.org/10.1016/j.avsg.2016.05.110

20.

Liu

Cao

, et al. Undetected intraoperative periprosthetic femoral fractures in patients undergoing primary total hip arthroplasty: a retrospective case series and literature review. Orthop Surg 2023; 15: 758–765. https://doi.org/10.1111/os.13646

21.

Kamper

Maher

Mackay

. Global rating of change scales: a review of strengths and weaknesses and considerations for design. J Man Manip Ther 2009; 17: 163–170. https://doi.org/10.1179/jmt.2009.17.3.163

22.

Fluss

Faraggi

Reiser

. Estimation of the Youden index and its associated cutoff point. Biom J 2005; 47: 458–472. https://doi.org/10.1002/bimj.200410135

23.

Swets

. Measuring the accuracy of diagnostic systems. Science 1988; 240: 1285–1293. https://doi.org/10.1126/science.3287615

24.

Nishimoto

Kurahashi

Tamari

, et al. Patient acceptable symptom state (PASS) thresholds for the Hip disability and Osteoarthritis Outcome Score (HOOS) after total hip arthroplasty. J Orthop 2026; 74: 33–38. https://doi.org/10.1016/j.jor.2025.12.056

25.

Paulsen

Roos

Pedersen

, et al. Minimal clinically important improvement (MCII) and patient-acceptable symptom state (PASS) in total hip arthroplasy (THA) patients 1 year postoperatively. Acta Orthop 2014; 85: 39–48. https://doi.org/10.3109/17453674.2013.867782

26.

Rossi

Nannini

Ulivi

, et al. Men and women undergoing total hip arthroplasty have different clinical presentations before surgery and different outcomes at 1-year follow-up. Knee Surg Sports Traumatol Arthrosc 2024; 32: 2635–2643. https://doi.org/10.1002/ksa.12124

27.

Wik

Klaksvik

Husby

, et al. Patient-reported outcome after primary and aseptic revision hip arthroplasty: 1-year follow-up of 3,559 primary and 406 revision THAs in an institutional registry. Acta Orthop 2022; 93: 132–137. https://doi.org/10.2340/17453674.2021.852

28.

Sundén

Lidengren

Roos

, et al. Hip complaints differ across age and sex: a population-based reference data for the Hip disability and Osteoarthritis Outcome Score (HOOS). Health Qual Life Outcomes 2018; 16: 200. https://doi.org/10.1186/s12955-018-1022-8

29.

Çorbacıoğlu

ŞK

Aksel

. Receiver operating characteristic curve analysis in diagnostic accuracy studies: a guide to interpreting the area under the curve value. Turk J Emerg Med 2023; 23: 195–198. https://doi.org/10.4103/tjem.tjem_182_23

30.

Ohfuji

Jingushi

Kondo

, et al. Factors associated with diagnostic stage of hip osteoarthritis due to acetabular dysplasia among Japanese female patients: a cross-sectional study. BMC Musculoskelet Disord 2016; 17: 320. https://doi.org/10.1186/s12891-016-1179-4

31.

Solarino

Bizzoca

Moretti

, et al. Sex and gender-related differences in the outcome of total hip arthroplasty: a current concepts review. Medicina (Kaunas) 2022; 58: 1702. https://doi.org/10.3390/medicina58121702

32.

Lungu

Maftoon

Vendittoli

, et al. A systematic review of preoperative determinants of patient-reported pain and physical function up to 2 years following primary unilateral total hip arthroplasty. Orthop Traumatol Surg Res 2016; 102: 397–403. https://doi.org/10.1016/j.otsr.2015.12.025

33.

Ponzio

Rothermel

Chiu

, et al.

Does physical activity level influence total hip arthroplasty expectations, satisfaction, and outcomes?

J Arthroplast 2021; 36: 2850–2857. https://doi.org/10.1016/j.arth.2021.03.052

34.

Peters

van Beers

LWAH

van Steenbergen

, et al. Similar superior patient-reported outcome measures for anterior and posterolateral approaches after total hip arthroplasty: postoperative patient-reported outcome measure improvement after 3 months in 12,774 primary total hip arthroplasties using the anterior, anterolateral, straight lateral, or posterolateral approach. J Arthroplast 2018; 33: 1786–1793. https://doi.org/10.1016/j.arth.2018.01.055

35.

Loh

Padki

Yew

, et al. Functional outcome of direct anterior versus posterior approach in total hip arthroplasty: a propensity-matched Asian study. Singapore Med J 2024. Online ahead of print. https://doi.org/10.4103/singaporemedj.SMJ-2021-125