Does total hip replacement affect sexual quality of life?

Background Total Hip Replacement (THR) is an effective treatment for end-stage hip osteoarthritis. Since the introduction of total joint replacement, the effect on the Sexual Quality of Life (SQoL) following THR has been addressed in scant studies. The aim of our study was to systematically review the literature, to summarise effects of THR on patients’ SQoL. Methods We searched PubMed, EMBASE and PsycINFO between January 1970 and February 9th, 2015 with search terms including Total Hip, Osteoarthritis, SQoL, and THR. Eligible studies were identified and two independent authors extracted data including details of SQoL, study quality and risk of bias. Results There were 12 eligible studies, which included a total of 2099 patients with an age range of 20–85 years. The methodological quality of ten studies was rated as low, and of two as moderate. Amongst the majority of patients, SQoL improved after surgery, both in terms of physical-functional and psychosocial well-being. However, changes between pre-operative and postoperative SQoL ranged extensively: for example, Sexual Dysfunction Δ 8–51 % and Sexual Activity (SA) Δ 0–77 %. Three studies reported that some patients never resumed SA again after surgery. Conclusion In over 40 years of THR treatment, scant studies have examined the effect of THR on patients’ SQoL. This review suggests that SQol improves after THR, although the magnitude of effects varies highly. However, the quality of the supporting evidence was rated as low to moderate. This suggests a need for more high quality evidence about the effects of THR on SQoL.


Background
Hip Osteoarthritis (HA) causes pain and affects function, social interactions and Sexual Function (SF) in patients [1,2]. It has been established that these functions can generally be restored by Total Hip Replacement (THR) [3,4]. The improvement in surgical techniques and the durability of the implants today have led to a growing number of patients undergoing joint replacement. Consequently, this patient population is growing and becoming both older and younger [5][6][7].
The effect of THR can-in part-be measured in terms of health-related quality of life [3,4]. Quality of Life (QoL) is a subjective and multidimensional indicator: it comprises a range of domains including functional ability and physical, emotional and social well-being [8]; it also includes Sexual Quality of Life (SQoL) [9]. The World Health Organization (2006) defines Sexual Health as "a state of physical, emotional, mental and social well-being in relation to sexuality" [10]; hence, it can be said that SQoL is an important part of general well-being, and improvements in SQoL have indeed been associated with improvements in general health related quality of life [10,11].
As human beings can be sexually active at all ages [12], the total number of sexually active patients undergoing THR will increase. Given the fact that SF is seldom discussed, [12], Sexual Difficulty (SD) might be under-diagnosed in patients with HA; however, while there are some recent international studies into this topic [13][14][15], an overview of the literature is lacking. The aim of this study, therefore, was to provide a systematic review of the literature, with the aim of summarising the effects of THR on patients' SQoL.

Methods
This systematic review was undertaken in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) system [16].

Data sources and searches
We searched electronically in PubMed, EMBASE and PsycINFO (by EBSCO). We also performed a hand search of reference lists of included articles to identify additional relevant studies. The search strategy was developed in collaboration with a medical database specialist (EPJ). The PubMed search strategy, which can be found in Appendix 1, was adapted for the other databases. The search included articles from January 1970 until February 9th, 2015. The searches included MeSH terms in PubMed, EMtree in EMBASE, thesaurus terms in PsycINFO as well as free text terms. Search terms expressing "total hip" and "osteoarthritis" were used in combination with "sexual quality of life" and "THR" treatment. Search results were imported to a reference manager (Mendeley), and duplicates were removed.

Study selection
Titles and abstracts were screened using the following eligibility criteria: Studies describing SQoL in patients with primary and or secondary HA undergoing THR were included if they measured SQoL after or before and after THR; studies that only assessed SQoL before surgery were excluded. Homogeneous cohorts of Ankylosing Spondylitis (AS) or Rheumatoid Arthritis (RA) in combination with SQoL were excluded because of the systemic illness and multiple joint involvements interfering with SQoL. Studies describing SQoL in patients undergoing THR and Total Knee Replacement (TKR) were excluded if data could not be split up. Studies solely assessing expectations about SQoL before and or after surgery were excluded. Studies not written in English, German or Dutch were excluded, because of capacity reasons. Reviews, editorials, case studies and legal cases were excluded. Studies with no full text available through the Dutch Interlibrary Loan System (IBL) were also excluded.
Two reviewers (RH and EPJ) independently applied the eligibility criteria to the titles and abstracts. Where there was uncertainty about eligibility, the full text was examined. Titles and abstracts that were identified as potentially eligible were selected for full-article review. The two reviewers independently screened the full-text articles for final study inclusion. Disagreements would have been resolved by a third author (TH), but this did not occur.
There are no other data found in supplementary files. Al data that support our findings are contained within this manuscript.

Data extraction
Two reviewers (RH and IS) extracted data from the included studies, independently and into pre-determined forms, and included the patients' demographics, such as disease characteristics, study aims and information about study designs (e.g. sample size, response rate, ages, gender, duration of follow-up, and analysis methods). SQoL outcomes were subsequently extracted and categorised into two dimensions of SQoL: physical-functional wellbeing and psychosocial well-being. We summarised the data into outcomes quantifying SQoL before and after surgery, as a result of surgery (changes in SQoL) and as postoperative (cross-sectional) outcomes.

Assessment of methodological quality
Two reviewers (RH and IS) independently scored the methodological quality of the included studies. Quality was assessed by using 17 of the 23-items quality checklist previously employed by Schouffoer [17] and Tilbury [18]. This checklist is based on Hayden [19] and Shamlyan [20] and is divided into 3 categories: selection bias (items 1-6), information bias (items [7][8][9][10][11][12][13][14], and statistical analysis bias (items [15][16][17]. This quality checklist can be found in Appendix 2. Items concerning multiple determinants were not included. Risk of bias was considered to be present if one or more of the items within one category were scored as "unclear", "negative" or "not described". When the study represented "high" quality on all items per category, the quality was rated as "0" (absence of risk of bias). When risk of bias was present, or items were not completely or not clearly described, it was rated as "1". The quality of the study was rated as "high" if there was no risk of selection bias, information bias, or statistical analysis bias. The quality was rated as "moderate" if there was evidence of risk of bias in one of the three categories, and as "low" if there was risk of bias in two or all categories.

Data syntheses
We planned to statistically pool data from studies that were clinically and methodologically homogeneous. However, because of the methodological heterogeneity of the studies, further statistical pooling of data was not possible.

Results
We identified 250 references (88 in PubMed, 159 in EMBASE, 3 in PsycINFO, and 3 additional records by reference checking) and removed 67 duplicates, after which 12 papers met the eligibility criteria for final analysis. The PRISMA flowchart is presented in Fig. 1.

Study characteristics
Studies were published between 1973 and 2015. Four studies were undertaken in North America and Canada, three of which in the USA [15,21,22] and one in Canada [4]. Six were undertaken in Europe: two in the UK [23,24], one in Denmark [25], one in Sweden [3], one in France [26], and one in the Netherlands [27]; two were undertaken in Asia: one in South Korea [13] and one in China/Japan [14].
Seven of the studies were longitudinally designed [3,4,14,21,24,25,27], and five retrospectively [15,22,23,26,28], comprising a total of 2099 patients undergoing THR, 60 % of which were males and 40 % females. Seven of the included studies described SQoL before and or after THR multi-dimensionally, and as the main question [13-15, 22-24, 26]; the other five described SQoL more indirectly, as one of the outcomes of a broader research question [3,4,21,25,27]. For example, two studies focused on Quality of Life (QoL) after THR [3,4], one on function and pain after THR [21]; one translated and validated the Oxford Hip Score questionnaire into Dutch [27], and one focused on alternative outcome measures after THR in young patients [25]. The number of participants in the studies ranged from 22 [21] to 791 [15] and their ages from 20 [22] to 86 [21]. Seventeen RA patients (divided into 5 studies) and five AS patients (indicated in 1 study) are present in this review, as they were part of a group of respondents of which the results were not presented separately. The duration of follow-up ranged between the first post-operative routine visit [22] to a mean of 2.3 (+0,8) years after THR [15]. The characteristics of the included studies that assessed SQoL in patients after THR are presented in Table 1.

Methodological quality
The methodological quality was rated as "moderate" in two studies [14,15] and "low" in ten studies [3,4,13,[21][22][23][24][25][26][27]. A full description of the methodological quality of all the studies is shown in Table 2, and the individual scores on all items of the methodological quality assessment can be found in Appendix 3. Unclear study participation, sampling and study attrition caused a risk of selection bias in five studies [13,[21][22][23]26]: for example, poor response rates or loss of follow up (more than 30 % was considered inappropriate), unrepresentative cohort study populations (e.g. including only satisfied patients) and unclear presented study details about reasons for loss to follow-up.

Outcomes
Studies used a number of terms to describe SQoL, and these terms were categorised into two main-groups, and several subgroups of SQoL: A. Physical-functional well-being, categorised into three sub-groups: Sexual Dysfunction (SD), Sexual Function (SF), and terms categorised as Sexual Activity (SA), for example, "coital frequency", "resuming time of SA", and "hip interfering with SA". B. Psychosocial well-being of SQoL, categorised into six sub-groups as: "Need for information" (or "not able to obtain information"), "SD was an argument to undergo THR", "Effects on relationship", "Effects on sexual satisfaction", "Effects on sex quality", and "Concerns" (e.g. "concerns from partner", "fear of dislocation", "decreased sexual desire", "arousal difficulty", "loss of libido", and "felt hip slipping out" during SA).
Subsequently, we summarised the differences between pre-and postoperative outcomes in Table 3 as "Changes in SQoL after THR", and the cross-sectional measured postoperative outcomes of SQoL were summarised in Table 4.
Two studies reported changes in psychosocial outcomes of SQoL [14,24]. One of those, reported an increase in the patients' "need for information" after THR of Δ 28 % [24]; the other study (only males) reported reduced "impairment of relationship" (Δ -37 %) (p = 0.026) and a change on "sexual satisfaction of patients" of Δ 40 % (p = 0.018) [14]. One study assessed associations between     Only SA patients were included f OHS = Oxford Hip Score: scale 0-6 (score 0 means "due to other reason than hip"; this was not included in statistics) Thus, 1 = no sex life able due to hip; 6 never disabled by the hip)  (7,9 %) pre-and postoperative SQoL and clinical and demographic characteristics, and found no correlation (p > 0.05) between these variables and postoperative SQoL [14].

Discussion
In this systematic literature review we summarised the effects of THR on SQoL as reported in 12 studies published between January 1970 and early 2015. We found that overall the majority of studies included in this review saw an improvement in SQoL after surgery for the majority of patients, in terms of both physical-functional and psychosocial well-being. However, the magnitude of this effect varied highly, which may be due to methodological and cultural differences between studies.
The difference between pre-operative and postoperative SD ranged from Δ 8-51 % [22,25], and the difference between pre-operative and postoperative SA ranged even more extensively: Δ 0-77 % [14,24]. This review further suggests that there are differences between men and women and between European/North American and Asian patients in terms of resuming SA. In addition, four studies reported that the majority of patients (50-80 %) did not receive sufficient information about what to expect of SQoL after THR [13,[22][23][24]. One study reported that the patients' need for information changed after the operation (Δ 28 %): the patients would have liked more information after surgery. Another subject of possible misinformation is the time to resume SA again and the fear of hip dislocation after THR [13]. Surprisingly, some studies described SF as an adverse event of THR: one study reported 4 % erectile dysfunction in males after THR [25], and two (retrospective) studies reported some patients who never resumed SA again after surgery [15,26]. This finding was somewhat unexpected; however, we found one additional study that supported this finding [29]. This additional study reported that 26.1 % of the males lost the erectile function they had preoperatively, while 6.7 % never regained normal erections again after surgery [29]. We did not find evidence for a true association or a causal link between erectile dysfunction and the surgery itself, and the author suggests his findings could be the result of major surgery at a higher age [29].
We found some gender differences in postoperative SA-men resumed sooner than women. We also found geographic differences [22,26]: the majority of Western (Europe and North America) patients resumed SA within 2 months, in accordance with recommendations of Western orthopaedic surgeons [24,30]; the majority of Eastern (Asia) patients resumed after 6.9 months [13]. We found neither recommendations nor additional literature of Asian orthopaedic surgeons. It is possible that discussing sexuality with physicians is a sensitive topic in Asian cultures [13,31]. However, it has been reported that Western patients do not raise the subject spontaneously either [32]: even surgeons rarely address the issue [30]. Therefore, problems with SQoL in patients undergoing THR could be under-diagnosed in the East and the West alike.
Some studies reported additional comments of patients: two studies reported that in nearly 20 % of patients SD was an argument to undergo THR [22,26]. Four studies mentioned that patients stated they would have welcomed a booklet with additional information [2,22,23,26]. In addition, Currey (1970) suggests that patients want to be adequately informed and prefer to obtain the information from the person with the most knowledge of the pathology [1]. However, it has been described that addressing SQoL is difficult and uncommon for both doctors and patients [33,34]. We suggest that this lack of communication causes unnecessary concerns: for example, it appears that patients are fearful of hip dislocation after surgery [13].
Dahm, Jacofsky and Lewallen found that 20 % of the members of the American Association of Hip and Knee Surgeons reported knowledge of patients experiencing dislocation during SA [30]. However, we found no literature indicating SA as a direct cause of dislocation, nor evidence-based guidelines about safely resuming SA after THR. We did find a recent (2014) motion-capture study that analyses the kinematics of the hip joint during the twelve"most common sexual positions" [35]. This study provides guidance on safe sexual positions, by gender, and describes that sexual positions for women require more hip mobility, and therefore have a higher risk for dislocation. This is confirmed by Lavernia et al. [36]. We suggest that it is a task of orthopaedic surgeons to provide good guidelines, as patients might otherwise try to seek information from the so-called "grey" literature that is available on the Internet. This "grey" information is potentially both inadequate and inaccurate [37].

Comparisons with other studies
Our systematic review is, to our knowledge, the first that summarises SQoL after THR. However, we are aware of one recent narrative review that reports the same beneficial but heterogenic effects of THR on SQoL [38], and we found a literature review of RA and sexuality, published in 1999, which reviewed 19 eligible papers with predominantly the same results [39]. Nonetheless, studies into SQoL and surgical hip treatment in the orthopaedic literature are few and far between: The first study was published in 1970, which corresponds to the time that the THR technique was being developed and gradually became safer [1]. However, since then, scant studies have acknowledged SQoL, and of the twelve studies included in this review, five were published more than 20 years ago. Although the methodology of the newer studies (after 2005) is more advanced, and recent studies show more depth of analyses of the topic, the overall results of the studies do not differ essentially between older and more recent studies.

Methodological implications
We rated ten of the twelve included studies methodologically as "low" because they had numerous sources of risk of bias; and eleven studies lacked multivariate analyses methods. Five of the twelve studies were retrospectively designed, however, in our opinion, these studies were useful for focussing on the study question of SQoL more thoroughly, identifying detailed information and "feasibility issues for future longitudinal research" about SQoL after THR [40]. Generally speaking, we suppose investigating SQoL is complex because it is a sensitive issue. However, Fenton et al. (2001) suggest that sexual behaviour research is as difficult as other areas of self-reported behaviour, including diet, smoking, and alcohol consumption" [41], and they conclude that "continued methodological research is needed to better identify the sources of measurement error." [41].
Additionally, the included studies paid little attention to comorbidities and other potential confounders. For example, a review concerning SQoL in psoriasis patients found that diabetes, hypertension or depression could play an important causal role towards erectile dysfunction [42], and another review suggests that the use of beta-blockers and diuretics may also have negative effects on SF [43]. Given the average age of THR patients, these confounders will likely be present in a considerable part of the hip population. The available studies further paid little attention to gender-specific complaints and outcomes; in addition, whereas females generally outnumber males in THR treatment [7], our review includes 60 % males, which indicates selection bias, and this is only partly explained by the fact that one great cohort-study included only men [14].

Strengths and weakness
Our review was characterized by a number of different − prospectively and retrospectively measured − heterogeneously defined factors of SQoL. This caused marked heterogeneity; consequently that data synthesis was not possible. Moreover, we may have missed potentially eligible studies in other languages as well as studies on QoL that mention SQoL in the full text only. Although we intended to exclude studies about SQoL in RA and or AS patients (because of the systemic illness and the multiple joint involvements interfering with SQoL), we decided to include 5 studies in which the majority of the patients had OA, but a minority were RA or AS patients (between 2 and 11 % of the population). In these studies data were not presented separately for the different diagnosis and therefore the total samples were included in this review. This may have slightly biased the results of our review.

Directions for further research
SQoL in patients with HA, before and after THR, is gaining importance as the total number of patients increases and the age range of patients broadens. Given the rising number of patients worldwide, we feel that SQoL should be better quantified routinely, for example by using Patient Reported Outcome Measures (PROMs) that are validated for this particular purpose. Longitudinal representative cohort studies would be helpful to accurately understand SD, beginning at the early stages, through to end-stage HA and postoperatively after THR.

Conclusion
This systematic review covers scant research of over more than 40 years. The limited number of studies show an overall improvement of SQoL after THR, however with a very large range in the magnitude of the effect. The quality of evidence in the included studies was low to moderate. Our results do indicate that patients have a need for more information, and with the total amount and growing yearly numbers of THR procedures worldwide, it is now clear that more research is warranted to provide information about the effects of THR on SQoL. It is only with this accurate information that we can effectively inform patients about what to expect for their SQoL after THR.

Ethics and consent to participate
Ethics approval and consent to participate was not required for this study, because this is a systematic review of previously published studies.

Consent to publish
Not applicable.

Availability of data and materials
Al data that support our findings are contained within the manuscript.