Higher risk of 2-year cup revision of ceramic-on-ceramic versus ceramic-on-polyethylene bearing: analysis of 33,454 primary press-fit total hip arthroplasties registered in the Dutch Arthroplasty Register (LROI)

Background and purpose: The influence of bearing on short-term revision in press-fit total hip arthroplasty (THA) remains under-reported. The aim of this study was to describe 2-year cup revision rates of ceramic-on-ceramic (CoC) and ceramic-on-polyethylene (CoPE). Patients and methods: Primary press-fit THAs with one of the three most used cups available with both CoC or CoPE bearing recorded in the Dutch Arthroplasty Register (LROI) were included (2007–2019). Primary outcome was 2-year cup revision for all reasons. Secondary outcomes were: reasons for revision, incidence of different revision procedures and use of both bearings over time. Results: 2-year Kaplan-Meier cup revision rate in 33,454 THAs (12,535 CoC; 20,919 CoPE) showed a higher rate in CoC (0.67% [95% CI, 0.54–0.81]) compared to CoPE (0.44% [95% CI, 0.34–0.54]) ( p = 0.004). Correction for confounders (age, gender, cup type, head size) resulted in a hazard ratio (HR) of 0.64 [95%CI, 0.48–0.87] ( p = 0.019). Reasons for cup revision differed only by more cup revision due to loosening in CoC (26.2% vs.1 3.2%) ( p = 0.030). For aseptic loosening a revision rate of 0.153% [95% CI, 0.075–0.231] was seen in CoC and 0.058% [95%CI 0.019–0.097] in CoPE ( p = 0.007). Correction for head size resulted in a HR of 0.475 [95% CI, 0.197–1.141] ( p = 0.096). Incidence of different revision procedures did not differ between bearings. Over time the use of CoPE has increased and CoC decreased. Conclusions: A higher 2-year cup revision rate in press-fit THA was observed in CoC compared to CoPE. Cup loosening was the only significantly different reason for revision and seen more often in CoC and mostly aseptic. Future randomised controlled trials need to confirm causality, since the early cup revision data provided has the potential to be useful when choosing the bearing in press-fit THA, when combined with other factors like bone quality and patient and implant characteristics.

Age as a predictor of additional surgeries following initial closed reduction for children with developmental dysplasia of the hip: the 10-year experience of a national paediatric orthopaedic unit

Background and purpose: Dislocated and unstable hip joints which do not stabilize in an orthosis in the neonatal period require operative intervention to achieve a stable concentric joint. The aim of this study is to assess the requirement for further operative intervention in patients who have undergone successful closed reduction to treat developmental dysplasia of the hip (DDH). Methods: We identified all patients who had undergone closed reduction of an unstable hip joint at our institution within 10 years, with further identification of patients who underwent a second procedure. We used logistic regression to evaluate correlation between age at closed reduction and the probability of secondary procedures. Results: A total of 694 patients (84.5% females) who underwent a closed reduction in the study period were identified. 235 were excluded (patients with underlying genetic conditions, neuromuscular disorders, syndromic disorders). 250 patients had closed reductions only. 209 patients (45.5%) had at least 1 secondary procedure after their initial closed reduction. In multivariable analysis, female gender (OR 0.310; 95% CI, 0.108–0.885; p = 0.029) and patients aged ⩽12 months at the time of first surgery (OR 0.055; 95% CI, 0.007–0.423; p = 0.005) independently predicted being less likely to require a second surgery for their DDH. Discussion: In conclusion, we found that a significant proportion of children (45.5%) who underwent closed reduction of a dislocated hip required additional surgical intervention in early childhood. Our data show that those children who undergo later closed reduction of a dislocated hip in DDH after 12 months of age, and male infants, have a significantly higher incidence of additional surgical intervention.

Does total hip arthroplasty with high hip centre in dysplasia compromise acetabular bone stock?

Background: The placement of uncemented acetabular components during total hip arthroplasty (THA) in Crowe II and Crowe III dysplasia can be at the anatomic or high hip centre position. Purposes: Using computerised tomography data, we simulated acetabular cup placement at the anatomic hip centre and the high hip centre positions to assess whether there is a difference between the 2 in terms of bone loss from acetabular reaming and in acetabular coverage by host bone. Methods: The study population included a consecutive cohort of 19 patients (22 hips) with Crowe II or III dysplasia. 3-dimensional models of the pelvis were created for each patient and digital templating was used to determine the anatomic and high hip centre positions. The coordinates of the digitally templated cup positions were fed into an image processing software to estimate the amount of bone reamed, the cup coverage by host bone and the elevation from tear drop. Results: The mean volume of bone reamed was greater in the high hip centre position as compared to the anatomic position (27.3 ± 11. 4 cm3 vs. 19.4 ± 12.2 cm3, p < 0.0001). The coverage of the acetabular cup by host bone was greater in the high hip centre position (87.3 ± 5.9% vs. 68.3 ± 10%). The mean elevation in the high hip centre group was 13 mm with 3 hips having a breach of the medial wall. Conclusions: In Crowe II and III dysplasia, placement of acetabular cups at the anatomic hip centre better preserves bone stock as compared to high hip centre placement and should be preferred in young patients requiring THA.

Survivorship and functional outcome of a cemented acetabular component with bulk roof autograft for severe acetabular dysplasia: 12- to 23-year follow-up

Aims: Primary aim was to determine survival of a cemented acetabular component with bulk roof autograft with a minimum of 12 years follow-up. The secondary aim was to determine the clinical outcome. Methods: A cohort of 62 consecutive patients (74 hips) undergoing cemented total hip arthroplasty with acetabular bulk roof autograft for acetabular dysplasia were retrospectively identified. The group consisted of 57 female patients (67 hips) and 5 male patients (7 hips) with a mean age at operation of 45 years. No patient was lost to follow-up, however 9 patients died had during the study period. The Oxford Hip Score (OHS), Forgotten Joint Score (FJS), EuroQol 5-Dimensional Score (EQ-5D), Short Form (SF-12) physical score and patient satisfaction were used to assess clinical outcome for patients with a surviving prosthesis. Results: The median follow-up was 16.6 (13.4–19.1) years. 6 revisions were performed during the follow-up period, all of which were due to aseptic loosening of the acetabular component. The all-cause Kaplan Meier survival rate for the acetabular component was 99% at 10 years, 95% at 15 years and 83% at 20 years. Neither age, gender, femoral osteotomy or polyethylene (UHMW vs. cross-linked) were significant predictors of aseptic revision of the acetabular component. There were no case of graft resorption and all grafts were radiologically incorporated. 45 patients were available for functional assessment at a mean follow-up of 18.2 years. The mean OHS was 37.8, FJS was 55.7, EQ5D was 0.73, and SF-12 physical component was 43.2. No patient was dissatisfied, with 2 patients reporting a neutral satisfaction, 7 stating they were satisfied and the remaining 36 were very satisfied. Conclusions: A cemented acetabular component with bulk roof autograft for dysplasia offers excellent survival with good to excellent functional outcome with high patient satisfaction in the medium- to long-term.

The walls of the femoral neck as an auxiliary tool for femoral stem positioning

Background: Femoral anteversion is a major contributor to functionality of the hip joint and is implicated in many joint pathologies. Accurate determination of component version intraoperatively is a technically challenging process that relies on the visual estimation of the surgeon. The following study aimed to examine whether the walls of the femoral neck can be used as appropriate landmarks to ensure appropriate femoral prosthesis version intraoperatively. Methods: We conducted a retrospective study based on 32 patients (64 hips) admitted to our centre between July and September 2020 who had undergone a CT scan of their lower limbs. Through radiological imaging analysis, the following measurements were performed bilaterally for each patient: anterior wall version, posterior wall version, and mid-neck femoral version. Anterior and posterior wall version were compared and evaluated relative to mid-neck version, which represented the true version value. Results: Mean anterior wall anteversion was 20° (95% CI, 17.6–22.8°) and mean posterior wall anteversion was −12° (95% CI, −15 to −9.7°). The anterior walls of the femoral neck had a constant of −7 and a coefficient of 0.9 (95% CI, −9.8 to −4.2; p < 0.0001; R2 0.77). The posterior walls of the femoral neck had a constant of 20 and a coefficient of 0.7 (95% CI, 17.8–22.5; p < 0.0001; R2 0.60). Conclusions: Surgeons can accurately obtain femoral anteversion by subtracting 7° from the angle taken between the anterior wall and the posterior femoral condyles or by adding 20° to the angle taken between the posterior wall and the posterior femoral condyles.

Greater trochanteric pain syndrome: focused shockwave therapy versus an ultrasound guided injection: a randomised control trial

Background: Greater trochanteric pain syndrome (GTPS) is a common problem with an incidence of 1.8–5.6 per 1000 population. Physiotherapy, anti-inflammatories, corticosteroid injections and surgery have all been described in the management of GTPS, with limited, temporal success. Extracorporeal shockwave therapy (ESWT) has been proposed as a potential non-invasive management option for this difficult presentation. Method: We ran a prospective, 2-arm, single-blinded, randomised control trial comparing focused shockwave therapy (f-ESWT) to an ultrasound guided corticosteroid injection. Primary outcome measure was the visual analogue pain score. Secondary outcome measures included the Harris Hip Score (HHS) and Trendelenburg test for function; SF-36 for quality of life (QoL); and a Likert scale question for subjective assessment of symptom improvement. Results: 104 patients (10 males and 94 females), of mean age 61.5 years were recruited. 53 were randomised to receive ESWT and 51 to receive an image-guided injection. 11 patients were lost to follow-up. There were no significant differences in baseline scores between groups. At 3 months, pain, function and QoL scores had improved in both groups but were not statistically significant. The Trendelenburg test was significantly improved in the f-ESWT group with 80% patients being negative compared to 20% at baseline ( p < 0.001). At 12 months, across all outcomes, the ESWT group had significantly improved scores compared to the injection group; VAS 37.1 versus 55.0 ( p = 0.007, 95% confidence interval [CI], 6.3–30.8), HHS 69.7 versus 57.5 ( p = 0.002, 95% CI, −20.0 to −4.6) and SF-36 52.4 versus 47.7 ( p = 0.048, 95% CI, −9.31 to −0.04). The improvement in Trendelenburg test was maintained in the ESWT group, but the injection group had reverted to baseline ( p < 0.001). Conclusions: We have shown f-ESWT is an effective treatment for patients with GTPS. We would advocate f-ESWT as an effective non-invasive treatment modality for this challenging patient population. Trial Registration No. ISRCTN8338223

Key performance and training parameters in primary total hip arthroplasty – an expert consensus using the Delphi technique

Aims: Primary total hip arthroplasty (THA) is a commonly performed and successful operation which orthopaedic trainees must demonstrate competence in prior to completion of surgical training. An assessment of agreement between surgical trainers regarding the critical steps of a primary THA has never been undertaken. The aim of this study was to define and rank the key steps of a primary THA regards ease of teaching and their importance in achieving the best patient outcome. Materials and methods: The Delphi technique with 3 iterative rounds was used to establish expert group consensus. The benchmark for consensus was set at an 80% agreement in any category for each step of a THR. The intra-class correlation coefficient (ICC) was used to report on the inter- and intra-rater reliabilities between and within participants responses respectively in rounds 2 and 3. Results: 50 consultant orthopaedic hip surgeons completed round 2, and 28 completed round 3. Overall, 27 steps (54 parameters) were identified, with 16 parameters achieving consensus agreement for their impact on patient outcome, and 17 for ease of teaching. The inter-rater ICC for patient outcome parameters was 0.89 and 0.92 in rounds 2 and 3 respectively while for teaching parameters it was 0.82 and 0.73. 50% of surgeons agreed that acetabular reaming, assessing and accurately restoring leg length, and acetabular cup anteversion were the 3 most difficult steps to teach trainees, while 90% agreed these 3 steps were substantially important to patient outcome. Another 5 steps achieved consensus for their substantial impact on patient outcome but failed to achieve consensus for ease of teaching. Conclusions: The results of this expert consensus have produced a rank-order list of the key steps in primary THA, which may be used for orthopaedic curriculum development and guiding focused improvements for surgical training in primary THR including simulation.

Primary total hip arthroplasty complications and costs in liver transplant recipients: a matched analysis using a national database

Background: The number of liver transplant recipients (LTR) is worldwide increasing and, as the survival is improving as well, there is an increasing number of patients needing total hip arthroplasty (THA). There might be increased risks for this specific group of patients and due to their comorbidities costs might be higher too. Using a big national database outcome and cost of THA should be compared between liver transplant recipients and the general population. Methods: The study was performed using a collection of Medicare, Medicaid, and private insurance claims. Length of stay (LOS), 30-day readmissions, complications rates up to 5 years, and 90-day total cost of care between liver transplant recipients and matched non-transplant patients should be compared. All primary THAs from 2010 to 2019 were identified. 513 patients with a liver transplant before their THA were matched to 10,759 patients without a history of solid organ transplant at a 1:20 ratio based on age, sex, Charlson Comorbidity Index, obesity, and diabetes status. Results: LTR had a longer average LOS (4.2 vs. 3.4 days, p < 0.001). There was no difference in the thirty-day readmissions (5.7% vs. 4.1%, p = 0.117) and 90-day dislocation rates (2.9% vs. 2.4%, p = 0.600). Total costs in the first ninety days after THA were not different between the LTR and controls ( p = 0.756). Conclusions: These findings suggest that complications and costs are no major point of concern in patients with liver transplant that are operated with THA.

Prevalence of frailty and associated factors among community-dwelling older adults after total hip arthroplasty

Objective: To evaluate the prevalence of frailty and associated factors among community-dwelling older adults who have undergone total hip arthroplasty (THA). Materials and methods: This study, which employed a cross-sectional, observational design, was conducted between April and November 2020. The participants were older adults (⩾65 years) who had undergone primary THA at the study hospital. Based on Fried’s modified phenotype, frailty was stratified into 3 degrees according to the presence of 3 or more of the following components: weight loss, weakness, exhaustion, low activity level, and slow walking speed. Multinomial logistic regression was used to analyse the associations of frailty with its potential risk factors. Results: The data of 518 participants were analysed. The overall prevalence of frailty and prefrailty was 11.4% and 51.0%, respectively. The multinomial logistic regression analysis showed that calf circumference (odds ratio [OR] 0.716, 95% confidence interval [CI], 0.611–0.839; p < 0.001), fall history (OR 2.435, 95% CI, 1.114–5.322; p = 0.026), hip abductor muscle strength (OR 0.962, 95% CI, 0.938–0.987; p = 0.003), knee extensor muscle strength (OR 0.980, 95% CI, 0.964–0.996; p = 0.013), and Timed Up and Go test (TUG) performance (OR 1.802, 95% CI, 1.458–2.228; p < 0.001) were associated with frailty. Conclusions: Frailty was highly prevalent in community-dwelling older adults after THA. Further, its potential associations with calf circumference, hip abductor and knee extensor muscle strength, TUG performance, and fall history highlight the significance of these factors for interventions.

Survival of the dysplastic hip after periacetabular osteotomy: a meta-analysis

Background: Periacetabular osteotomy (PAO) has become a popular procedure for re-orientation of the acetabulum in patients with a developmental pathomorphology. Since its first description by Reinhold Ganz in 1988, many institutions worldwide have adopted the procedure for the treatment of developmental hip dysplasia (DDH) and have subsequently reported their results. The aim of this study was to provide a meta-analysis of the likelihood of long-term survival of a dysplastic hip after PAO. Methods: A systematic literature review was conducted using Medline, Cochrane and “Web of Science” databases to identify articles reporting survival estimates for PAO in patients with DDH. To be included in the analysis, studies had to include patient cohorts aged <40 years, with Osteoarthritis grade < Tönnis III and no form of neuromuscular dysplasia. Adjustment for cohort overlap was performed. Quality assessment included level of evidence (LOE) according to the oxford center for LOE criteria and the “Methodological index for non-randomized studies (MINORS)”. After data extraction, a random-effects meta-analytical model was applied to provide weighted mean estimates of survival at 5 years, 10 years, 15 years and 20 years. Results: Nine relevant articles included 2268 dysplastic hips that underwent PAO in 9 institutions. Of the included studies, 5 presented level III evidence and 4 presented level IV evidence. The MINORS score was 11 for 3 studies, 12 for 4 studies and 13 for 2 studies. The 5-year survival after PAO was 96.1% (95% CI, 94.9–97.3), the 10-year survival was 91.3% (95% CI, 87.7–94.8), 15-year survival 85.0% (95% CI, 78.9–91.1), 20-year survival 67.6% (95% CI, 53.9–81.3). Conclusions: The results provide a representative survival estimate of a dysplastic hip after PAO based on global evidence. This should provide clinicians and patients with an adequate reflection of prognostic expectations after this kind of surgery.