Primary Total Hip Arthroplasty, Primary Total Hip Replacement
Conditions
Keywords
total hip arthroplasty, THA, total hip replacement, THR, randomised controlled trial, RCT, unipolar cup, dual-mobility cup
Brief summary
THA comprises the replacement of the damaged bone and cartilage with prosthetic components. The proximal end of the femur is replaced with a stem and ball/head, while the acetabulum is most commonly replaced with a unipolar cup (UP) that consists of a liner inside of a metal shell. UP cups are associated with risks of dislocations, especially in elderly and female patients, as well as in patients with lumbar stiffness or operated for femoral neck fractures. In fact, one of the most common reasons for early revision of UP cups are dislocations. Dual-mobility (DM) cups were introduced in the 1970s by the French surgeon Gilles Bousquet, as an alternative to UP cups. They are made up of two articulations, a femoral head moving inside a mobile polyethylene liner, which in turn moves inside a metal shell. This design allows for a greater jump distance and range of motion (ROM) compared to UP cups, thus resulting in reduced rates of dislocation. A recent systematic review that evaluated 5 case-control studies (549 DM cups vs 649 UP cups) and 3 registry studies (5935 DM cups vs 217362 UP) found that in case-control studies, the dislocation rates were 0.2% for DM cups versus 7.1% for UP cups (p=0.009). Furthermore, in registry studies the revision rates due to dislocation were 0.2% for DM cups versus 0.5% for UP cups (p=0.050). Nonetheless, there have been some concerns associated with the use of DM cups, including intra-prosthetic dislocations (IPD), polyethylene wear, and iliopsoas impingement. Since the early 2000s, new improvements in the design of DM cups have nearly eliminated the risk of IPD, and the use of ultra-high molecular weight polyethylene (UHMWPE) has greatly reduced wear rates, even in young and active patients. Lastly, although some studies have reported iliopsoas impingement with DM cups, the impingement is usually against the optional fixations, and not against the mobile polyethylene insert. The hypothesis of the present interventional randomised controlled trial (RCT) is that THA using DM cups will not provide inferior outcomes compared to THA using UP cups, in terms of hip awareness measured using the forgotten joint score (FJS).
Interventions
PROCEDUREPrimary total hip arthroplasty using dual-mobility cup
Replacement of hip articulating surface.
PROCEDUREPrimary total hip arthroplasty using unipolar cup
Replacement of hip articulating surface.
Sponsors
Elsan
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Intervention model description
This study is a patient-blinded prospective monocentric interventional comparative randomised trial in parallel groups, to evaluate the non-inferiority of DM cups compared to unipolar cups for THA.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* men and women aged ≥18 years old * set to undergo elective primary THA via direct anterior approach (DAA) * affiliated with a social security scheme * able to answer questionnaires and to communicate freely in French * who have been informed and have provided free, informed, and written consent (no later than the day of inclusion and before any examination required by the study)
Exclusion criteria
* with prior ipsilateral hip surgery * with prior contralateral hip surgery * that require acetabular cup diameters ≤50mm (because DM cups are not available from the same manufacturer for diameters ≤50mm, and UP cups require head diameters of 36mm and thus minimum cup diameters of 52mm) * undergoing emergency or trauma surgery (e.g. femoral neck fractures) * with any concomitant disease or disorder which, in the opinion of the surgeon, may put the patient at risk, notably of hip instability or dislocation (hip dysplasia, neuromuscular deficit, fracture sequelae…) or may influence the result of the study * that are pregnant or breastfeeding * under legal protection (guardianship or curatorship or deprived of liberty).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Forgotten Joint Score between DM cup group and UP cup group | 2 years | The primary outcome is defined as patient-reported hip awareness at 2 years postoperatively, measured using the Forgotten Joint Score (FJS). The FJS is a validated self-administered questionnaire that measures the patients' ability to forget about a joint as a result of successful treatment. The questionnaire comprises 12 items. Each item is scored using a 5-point Likert scale, ranging from "never" (0 points) to "mostly" (4 points). The final FJS score is calculated as the addition of all items, divided by the number of items answered. The mean score is then multiplied by 25, and that value is subtracted from 100. The FJS ranges from 0 to 100, with 100 corresponding to the best score: the patient has forgotten about their joint. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Forgotten Joint Score between DM cup group and UP cup group | 3 months and 1 year | Patient-reported hip awareness at 3 months and 1 year postoperatively, measured using the FJS. The FJS is a validated self-administered questionnaire that measures the patients' ability to forget about a joint as a result of successful treatment. The questionnaire comprises 12 items. Each item is scored using a 5-point Likert scale, ranging from "never" (0 points) to "mostly" (4 points). The final FJS score is calculated as the addition of all items, divided by the number of items answered. The mean score is then multiplied by 25, and that value is subtracted from 100. The FJS ranges from 0 to 100, with 100 corresponding to the best score: the patient has forgotten about their joint. |
| To compare the patient's hip/groin pain between DM cups versus UP cups, as well as to compare the net change from baseline | preoperatively, at 3 months, 1 year and 2 years | Patient-reported hip/groin pain preoperatively and at 3 months, 1 year and 2 years postoperatively, measured using a numeric rating scale (NRS). The net change will be calculated at 3 months, 1 year and 2 years taking the preoperative value as baseline. The NRS ranges from 0 to 10, with 0 representing no pain, and 10 representing the maximum pain imaginable. |
| To compare the patient's hip function between DM cups versus UP cups | preoperatively, at 3 months, 1 year and 2 years | Patient-reported hip function preoperatively and at 3 months, 1 year and 2 years postoperatively, measured using the Oxford hip score (OHS). The OHS is a validated self-administered questionnaire that assesses disability, in terms of function and pain, in patients undergoing THA. The questionnaire comprises 12 items. Each item is scored using a 5-point Likert scale, from 0 to 4 points, with 0 representing the worst outcome and 4 the best. The final OHS score is calculated as the addition of all items. The OHS ranges from 0 to 48, with 48 corresponding to the best score. Clinician-reported hip ROM preoperatively and at 3 months and 1 year postoperatively. ROM will be measured in degrees, in flexion, extension, internal rotation, external rotation, abduction, adduction. |
| To compare the patient's sports activity between DM cups versus UP cups | 1 year | Patient-reported return to sports (yes/no) and time to return to sports (months) will be assessed at 1 year postoperatively. |
| To compare the patient's sexual activity between DM cups versus UP cups | 1 year | Patient-reported return to sexual activity (yes/no) and time to return to sexual activity (months) will be assessed at 1 year postoperatively. |
| To compare the patient's satisfaction with surgery between DM cups versus UP cups | 1 year | Patient-reported satisfaction with surgery at 1 year postoperatively, measured using a NRS. The NRS ranges from 0 to 10, with 0 representing extremely dissatisfied, and 10 representing extremely satisfied. |
| To compare adverse events (that may impact the objectives of the study) between DM cups versus UP cups | intraoperatively, at 3 months, 1 year and 2 years | Adverse events that may impact the objectives of the study, as well as complications (e.g. fracture, infection, hematoma, limb length discrepancy, aseptic loosening, articular noise), reoperations, and implant revisions, will be collected throughout the study period, specifying the incidence, severity, and relationship to the surgery performed. Adverse events of interest will be dislocations and iliopsoas impingement. |
Countries
France
Contacts
CONTACTNicolas Verdier
CONTACTCharlène Py
Outcome results
None listed