From mobility to intimacy: assessing the effects of periacetabular osteotomy on sexual function in patients with hip dysplasia

Abstract

Aims

Developmental dysplasia of the hip (DDH) often leads to early osteoarthritis, causing pain and functional limitations that may impair sexual function. This study investigates the impact of periacetabular osteotomy (PAO) on sexual function in DDH patients, assessing changes from preoperative impairments to postoperative improvements.

Methods

This retrospective study analyzed data from DDH patients treated with PAO between January 2015 and June 2017 at a single orthopaedic university centre. Data included radiological parameters and patient-reported outcome measures: International Hip Outcome Tool (iHOT-12), Subjective Hip Value, Hip disability and Osteoarthritis Outcome Score (HOOS) and its sub-scores, and Numeric Pain Scale. Sexual function was specifically assessed using iHOT-12 item nine, asking, “How much trouble do you have with sexual activity because of your hip?”

Results

The study included 120 hips in 107 patients, predominantly female (85.1%). Radiological improvements post PAO were significant, with increases in the lateral centre-edge angle (LCEA) (16.6° (SD 6.0°) to 29.4° (SD 5.8°); p < 0.001) and reductions in the Tönnis angle (13.3° (SD 6.7°) to 1.2° (SD 7.4°); p < 0.001). Patient-reported outcomes demonstrated significant improvements postoperatively. Specifically, the iHOT-12 sexual function item showed substantial improvement from a mean preoperative score of 54.3 (SD 33.7) to a postoperative score of 75.0 (SD 27.1) (p < 0.001). Females reported significant enhancements in sexual function (p < 0.001), whereas improvements in males did not reach statistical significance (p = 0.181). Cases of under-correction (LCEA < 25°) demonstrated significantly higher impairments in sexual function postoperatively compared with adequately corrected cases, indicating the importance of achieving optimal anatomical correction.

Conclusion

PAO significantly enhances sexual function and overall hip-related quality of life in patients with symptomatic DDH. The findings underscore the necessity of precise surgical techniques and highlight that outcomes may vary by sex, suggesting a need for a sex-sensitive approach in both clinical practice and research.

Cite this article: Bone Jt Open 2025;6(4):440–445.

Introduction

Developmental dysplasia of the hip (DDH) is recognized as the primary cause of early, secondary osteoarthritis in the hip, leading to pain and functional limitations within the joint.¹ While the direct impact of these functional limitations and hip-related symptoms on sexual activity remains to be fully understood, it is hypothesized that they could potentially impair sexual function due to associated pain, instability, and reduced hip function. As advancements in the understanding of hip dysplasia’s pathology, treatment options, and diagnostics have evolved, patients are increasingly being presented to orthopaedic surgeons in a timely manner for joint-preserving surgery.

Periacetabular osteotomy (PAO) has emerged as the standard for surgical, joint-preserving treatment in cases of hip dysplasia.^2,3 This surgical intervention has demonstrated significant improvements in joint function and pain relief, alongside ensuring long-term preservation of the joint.^2-6 Patients undergoing PAO are typically young and of reproductive age, highlighting the importance of investigating the broader impacts of the surgery, including on sexual health.⁷ While the primary goal of PAO is to improve hip joint function and preserve the native joint, the potential impact on sexual activity and associated patient-reported outcomes has not been extensively studied.

Given the limited understanding of how hip dysplasia affects sexual function and the potential impact of PAO, this study aims to assess the prevalence of hip-related impairment of sexual function in DDH patients as well as the impact of PAO on sexual function in patients with symptomatic DDH, exploring both preoperative impairments and postoperative improvements. Additionally, the study aims to identify patient-specific factors that influence the impairment of sexual function in patients with hip dysplasia.

We hypothesized that: 1) PAO significantly improves sexual function in patients with symptomatic DDH in mid-term follow-up, mitigating preoperative impairments and enhancing postoperative outcomes; and 2) specific patient characteristics, including demographic, anatomical, and functional parameters, significantly correlate with the degree of sexual function impairment in patients with hip dysplasia both before and after periacetabular osteotomy.

Methods

Study design

We performed a retrospective analysis of prospectively collected data from the institutional PAO database of a single orthopaedic university centre. Prior to initiation of the study, approval of the local ethics committee was obtained (EA1/052/21). The study was conducted in accordance with the STROBE guidelines.⁸ Included were patients with a primary diagnosis of DDH treated with PAO between January 2015 and June 2017 who had completed hip-specific questionnaires, including data on hip-related impairment of sexual function, as well as informed consent. Exclusion criteria were a primary diagnosis other than DDH (i.e. acetabular retroversion), prior surgery on the ipsilateral hip, or incomplete data at follow-up. Only complete datasets were included in the final analysis. To be able to report a mid-term follow-up, the inclusion period was chosen accordingly.⁹

Study cohort

During the study period, a total of 202 PAOs were performed. Of these, six were operated on for a diagnosis other than DDH, 73 cases were lost to follow-up, and three had incomplete data, resulting in a final cohort of 120 hips in 107 patients. Bilateral PAO was performed in 13 patients. A detailed overview of patient selection is shown in Figure 1. Of these cases, 85.1% (102 hips) were female, and 14.9% (18 hips) were male. PAO was performed on the right hip in 52% (62 hips) of cases. PAO was performed through a single-incision minimally invasive approach according to the Bernese technique.^10-12

Fig. 1.

CONSORT flowchart illustrating patient selection and reasons for exclusion. DDH, developmental dysplasia of the hip; PAO, periacetabular osteotomy.

Radiological data assessment

Radiological assessments were conducted using anterior-posterior pelvis radiographs to measure parameters indicative of hip dysplasia: lateral centre-edge angle (LCEA),¹³ Tönnis angle (TA),¹³ anterior wall index (AWI),¹⁴ posterior wall index (PWI),¹⁴ and femoral head extrusion (FHEI).¹³

Clinical data and assessment of sexual function impairment

Pre- and postoperative patient-reported outcome measures (PROMs) included the International Hip Outcome Tool (iHOT-12),¹⁵ Subjective Hip Value (SHV),^16,17 and the Hip disability and Osteoarthritis Outcome Score (HOOS) along with its sub-scores.¹⁸ Sexual function was specifically assessed using item nine of the iHOT-12. The exact wording of this item was: “How much trouble do you have with sexual activity because of your hip?”.¹⁵ In this assessment, lower scores indicate greater impairment of sexual function, while higher scores reflect less impairment.

Statistical analysis

Descriptive statistics (means, SD, frequencies) were used to summarize patient characteristics and outcomes. The normal distribution of data was tested using the Shapiro-Wilk test. Pre- and postoperative comparisons of radiological and clinical data were conducted using paired t-tests for normally distributed data, and the Mann-Whitney U test for non-normally distributed data. Changes in sexual function scores were analyzed using the Wilcoxon signed-rank test for non-parametric data. Associations between impairments in sexual function and patient-specific factors were investigated using bivariate correlation analysis. Group comparisons with more than two groups were performed using the Kruskal-Wallis test followed by a Bonferroni correction. A p-value < 0.05 was considered statistically significant. For documentation of the collected data, Excel v.16.16.2 (Microsoft, USA) was used. Data analysis was performed using SPSS v.29 (IBM, USA).

Results

The mean follow-up was 62.8 months (SD 10). The mean age of the patients was 28.9 years (SD 8.6). The cohort included 102 females and 18 males.

Radiological findings

The relevant radiological parameters showed significant improvement from preoperative to postoperative assessments. Specifically, the LCEA increased (p < 0.001), the Tönnis angle decreased (p < 0.001), the FHEI reduced (p < 0.001), the AWI increased (p = 0.031), and the PWI decreased (p = 0.013). These changes reflect substantial radiological enhancements post-surgery. Detailed data on each parameter are presented in Table I.

Table I.

Summary of pre- and postoperative radiological parameters.

Radiological parameter	Preoperative, mean (SD)	Postoperative, mean (SD)	p-value*
Lateral centre-edge angle, °	16.6 (6.0)	29.4 (5.8)	< 0.001
Tönnis angle. °	13.3 (6.7)	1.2 (7.4)	< 0.001
Femoral head extrusion, %	23.9 (8.2)	9.7 (8.5)	< 0.001
Anterior wall index	0.38 (0.15)	0.46 (0.14)	0.031
Posterior wall index	0.83 (0.19)	0.74 (0.25)	0.013

^*Mann-Whitney U test was used to compare pre- and postoperative radiological parameters. Level of significance was defined as p < 0.05.

Patient-reported outcomes and hip function

Hip function, as measured by multiple PROMs, demonstrated significant improvements from preoperative to postoperative evaluations. Specifically, the iHOT-12, SHV, and Numeric Pain Scale¹⁹ showed significant improvements (p < 0.001). The HOOS sub-scores for symptoms, pain, function in daily living, and quality of life were also significantly enhanced (p < 0.001). Detailed pre- and postoperative data are summarized in Table II.

Table II.

Summary of pre- and postoperative patient-reported outcome measures.

PROM	Preoperative, mean (SD)	Postoperative, mean (SD)	p-value*
iHOT-12	41.1 (22.4)	72.0 (23.6)	< 0.001
Subjective Hip Value	42.7 (24.3)	80.1 (17.9)	< 0.001
Numeric Pain Scale	7.2 (1.9)	2.2 (2.1)	< 0.001
HOOS - Symptoms	51.6 (26.9)	71.7 (18.9)	< 0.001
HOOS - Pain	43.7 (23.8)	79.3 (19.7)	< 0.001
HOOS - Daily Living	55.1 (28.8)	83.6 (18.9)	< 0.001
HOOS - Quality of Life	29.7 (23.3)	61.6 (25.9)	< 0.001

^*Mann-Whitney U test was used to compare pre- and postoperative patient-reported outcome measures. Level of significance was defined as p < 0.05.

HOOS, Hip disability and Osteoarthritis Outcome Score; iHOT-12, International Hip Outcome Tool; PROM, patient-reported outcome measure.

Hip-related impairment of sexual functioning

According to item nine of the iHOT-12, patients experienced a significant improvement in their sexual function after PAO (p < 0.001). Preoperatively, patients had a mean score of the item nine of the iHOT-12 of 54.3 (SD 33.7), while postoperatively, the mean was 75.0 (SD 27.1) on a scale of zero to 100.

Influence of sex on impairment of sexual function

Females reported preoperative impairment of sexual function with a mean score of 52.4 (SD 33.1), while males reported a mean score of 65.0 (SD 36.2; p = 0.118), indicating greater impairment in female patients. Postoperatively, females showed reduced impairment of sexual function with a mean score of 74.6 (SD 27.4), and males with a mean of 77.2 (SD 26.1; p = 0.617). While females showed a significant increase from preoperative to postoperative scores (p < 0.001), males did not show a significant postoperative improvement (p = 0.181).

Influence of age on hip-related impairment of sexual functioning

No age-associated differences were seen in female patients for the hip-related impairment of sexual functioning preoperatively (p = 0.080) and postoperatively (p = 0.809). However, significant differences were seen for the improvement of hip-related impairment of sexual function from pre- to postoperatively (p = 0.038). In post-hoc testing with Bonferroni correction, females aged between 20 and 30years improved significantly more compared with those aged > 40years (p = 0.030).

Moreover, significant differences were observed within the respective age groups. For female patients aged under 20 years (n = 17), the preoperative mean was 56.6 (SD 2.62) and the postoperative mean was 81.2 (SD 2.55), showing a significant improvement (p = 0.001). In the group aged 20 to 30 years (n = 48), the preoperative mean was 54. 8 (SD 3.51) and the postoperative mean was 72.6 (SD 2.84), also with significant improvement (p = 0.001). Similarly, for patients aged 30 to 40 years (n = 27), the preoperative mean was 59.7 (SD 3.34) and the postoperative mean was 75.3 (SD 2.75), indicating a significant improvement (p = 0.001). However, for patients aged over 40 years (n = 10), the preoperative mean was 30.0 (SD 3.35) and the postoperative mean was 73.6 (SD 2.34), with the improvement not reaching statistical significance (p = 0.149).

Influence of patient-specific parameters on hip-related impairment of sexual functioning

The bivariate analysis revealed that the preoperative pain (NRS) with a correlation coefficient of −0.404 (p < 0.001) and hip joint function as measured by the SHV with a correlation coefficient of 0.398 (p < 0.001) significantly influenced hip-related impairment of sexual function. These measures reflect substantial impacts on sexual function prior to surgery. Radiological parameters such as the preoperative LCEA, Tönnis angle, AWI, PWI, FHEI, and Tönnis grade of osteoarthritis, as well as demographic factors such as age and BMI, showed no significant association with preoperative sexual function.

Postoperatively, both pain (NRS) with a correlation coefficient of −0.428 (p < 0.001) and hip joint function as measured by the SHV with a correlation coefficient of 0.511 (p < 0.001) showed significant relationships in the bivariate analysis. These results indicate a significant influence on the hip-related impairment of sexual function by these functional parameters.

The radiological parameters achieved postoperatively through PAO also demonstrated significant correlations with hip-related impairment of sexual function. The postoperative LCEA in particular correlated significantly with a correlation coefficient of 0.213 (p = 0.036).

More specifically, patients with an under-correction defined by a LCEA < 25° (n = 20) postoperatively showed a significantly higher impairment of hip-related sexual function as measured by item nine of the iHOT-12 (p = 0.033) compared with the rest of the cohort without under-correction (mean 77.8 (SD 25.3)), while the cohorts of patients with under-correction did not differ preoperatively (mean 52.0 (SD 33.7)) from the comparison group (mean 54.7 (SD 33.5); p = 0.691).

Age and BMI also showed no significant relationship with hip-related impairment of sexual function postoperatively, suggesting that these demographic factors may have less influence on postoperative sexual function.

Discussion

The most important findings from this research indicate that sexual function is significantly impaired in symptomatic DDH patients, and that PAO not only alleviates pain and improves joint function, but also significantly enhances sexual function postoperatively in these cases. A substantial majority of patients reported improved sexual activity outcomes, as reflected by the improvements in the iHOT-12 item specific to sexual function, which is consistent with the overall enhancements in PROMs observed.

Our initial hypotheses are supported by the findings of this study. Specifically, PAO significantly improved sexual function, mitigating preoperative impairments and enhancing postoperative outcomes. Moreover, specific patient characteristics, such as preoperative and postoperative pain and hip function, significantly correlated with the degree of sexual function impairment both before and after surgery. The results also highlighted that the corrections achieved through PAO had a significant impact not only on hip function but also on sexual function. Postoperative improvements in radiological parameters, particularly the LCEA, were significantly associated with improvements in hip-related impairment of sexual function. Notably, patients with an under-correction (LCEA < 25°) exhibited significantly greater impairment postoperatively compared to those without under-correction. This suggests that the degree of correction achieved through surgery may play a crucial role not only in hip function and joint preservation, as previously described in the literature, but also in mitigating impairments of sexual function.^20-22 While existing studies on the impact of PAO on sexual function are sparse, our findings contribute to this limited body of knowledge. Klit et al²³ assessed various patient outcomes, including sports, social, and sexual activity after PAO. The authors reported that both females and males experienced enhancements in their sex life at nine to 12 years following PAO surgery. Importantly, the improvements observed in females were statistically significant, in contrast with those observed in males, which did not reach the same level of statistical significance.²³ This disparity between the sexes is in line with the findings of our study and suggests sex variability in outcomes, which is a crucial aspect for further investigation in clinical research and practice. Looking beyond the specific context of PAO, insights from other areas of hip preservation surgery reveal similar trends in sexual function impairments among young individuals with different hip pathologies. A study by Smith et al²⁴ explored the outcomes concerning sexual function in patients with femoroacetabular impingement before and after hip arthroscopy. This research found significant improvements in sexual function of both female and male patients postoperatively. Notably, female patients experienced greater improvements compared with their male counterparts. The authors suggested that differences in sexual positioning, which often require more flexion, abduction, and rotation in females than in males, might explain these sex disparities. This explanation seems plausible in the context of DDH and PAO as well.

Another study conducted by Valenzuela et al⁷ aimed to investigate the impact of PAO on sexual activity, pregnancy, and childbirth, involving a cohort of 90 female patients who underwent PAO. While no male patients were assessed for sexual function pre- or postoperatively, their research revealed that between 25% and 40% of female patients experienced improvements in sexual function and satisfaction post-surgery, highlighting the potential benefits of PAO beyond traditional mobility and pain relief outcomes. While this study did not assess sexual function and the related impact of PAO in detail, the study findings underscore the significance of considering broader quality-of-life aspects when evaluating the success of PAO. Our study aligns with and expands upon these findings by linking anatomical corrections, notably improvements in the LCEA, to enhanced sexual function. This correlation suggests the importance of addressing potential quality-of-life enhancements, including sexual health, in clinical discussions with patients undergoing PAO.

This study offers valuable insights into the benefits of PAO on sexual function, yet there are several limitations to consider. The retrospective design limits causal interpretations between PAO and improvements in sexual function; prospective studies are needed to confirm these results and clarify the progression of symptoms. Although the sample size was suitable for preliminary exploration, the male subgroup was too small for a more detailed sex-based analysis. Moreover, the reliance on patient-reported outcomes for assessing sexual function could introduce bias. The use of only one item from the iHOT-12 to assess sexual function represents a further limitation, as it may not capture the multifaceted nature of sexual health. Future studies should consider using a broader range of validated instruments and potentially include assessments that explore psychological aspects, such as anxiety, to provide more comprehensive evaluations. These approaches would likely offer more accurate assessments and a fuller understanding of the impact of PAO on sexual function.

In conclusion, this study demonstrates that PAO not only improves pain and joint function, but also significantly enhances sexual function in patients with symptomatic hip dysplasia. By correcting anatomical impairments, PAO plays a crucial role in alleviating physical discomfort and enhancing sexual health, a vital aspect of overall quality of life.

The direct correlation between the degree of anatomical correction and improvements in sexual function underscores the importance of precise surgical techniques for optimal outcomes. Additionally, the findings suggest that sex impacts PAO outcomes, with female patients experiencing more pronounced improvements in sexual function, highlighting the need for a sex-sensitive approach in clinical practice and research.

Take home message

- This study highlights that periacetabular osteotomy significantly improves sexual function in patients with hip dysplasia, underlining the broader impact of surgical intervention beyond pain relief and mobility.

Data Availability

The data that support the findings for this study are available to other researchers from the corresponding author upon reasonable request.