Aims

This study investigates head-neck taper corrosion with varying head size in a novel hip simulator instrumented to measure corrosion related electrical activity under torsional loads.

Aims

Cam and pincer morphologies are potential precursors to hip osteoarthritis and important contributors to non-arthritic hip pain. However, only some hips with these pathomorphologies develop symptoms and joint degeneration, and it is not clear why. Anterior impingement between the femoral head-neck contour and acetabular rim in positions of hip flexion combined with rotation is a proposed pathomechanism in these hips, but this has not been studied in active postures. Our aim was to assess the anterior impingement pathomechanism in both active and passive postures with high hip flexion that are thought to provoke impingement.

Aims

This study aims to assess the feasibility of conducting a pragmatic, multicentre randomized controlled trial (RCT) to test the clinical and cost-effectiveness of an informal caregiver training programme to support the recovery of people following hip fracture surgery.

Aims

Bone marrow-derived mesenchymal stem cells obtained from bone marrow aspirate concentrate (BMAC) with platelet-rich plasma (PRP), has been used as an adjuvant to hip decompression. Early results have shown promise for hip preservation in patients with osteonecrosis (ON) of the femoral head. The purpose of the current study is to examine the mid-term outcome of this treatment in patients with precollapse corticosteroid-induced ON of the femoral head.

Periprosthetic joint infections (PJI) are challenging complications following arthroplasty. Staphylococci are a frequent cause of PJI and known biofilm producers.

Reoperations for PJI of the hip or knee between 2012 and 2015 performed at Sahlgrenska University Hospital were identified. Medical records were reviewed, and clinical parameters recorded for patients whose intraoperative bacterial isolates had been stored at the clinical laboratory. Staphylococcal strains isolated from reoperations due to first-time PJI were characterised by their ability to form biofilms using the microtiter plate test.

The study group included 49 patients (70 bacterial strains) from first-time PJI, whereof 24 (49%) patients had recurrent infection. Strong biofilm production was significantly associated with recurrent infection. Patients infected with strong biofilm producers had a five-fold increased risk for recurrent infection.

Strong biofilm production was significantly associated with increased antimicrobial resistance and PJI recurrence. This underscores the importance of determining biofilm production and susceptibility as part of routine diagnostics in PJI. Strong staphylococcal biofilm production may have implications on therapeutic choices and suggest more extensive surgery. Furthermore, despite the increased biofilm resistance to rifampicin, results from this study support its use in staphylococcal PJI.

Prosthetic joint infections (PJIs) with prior multiple failed surgeries for re-infection (PMFSR) represented a huge challenge for surgeons because of poor vascular supply and biofilm formation. This study aims to determine the results of single-stage revision using intra-articular antibiotic infusion for treatment of PJIs with PMFSR.

A retrospective analysis included 78 PJIs (29 hips; 49 knees) with PMFSR, who were treated with single-stage revision using intra-articular antibiotic infusion. Previous failure was defined as infection recurrence requiring surgical intervention. Besides intravenous pathogen-sensitive agents, a intra-articular infusion of vancomycin, imipenem or voriconazole was performed post-operatively. The antibiotic solution was soaked into the joint for 24 hours then extracted before next injection. Recurrence of infection and clinical outcomes were evaluated.

Of these 78 patients, 59 had more than twice failed debridement and implant retentions, 12 patients had a failed arthroplasty resection, 3 hips underwent a failed two-stage revision and 4 cases had a failed one-stage revision before their single-stage revision. A total of 68 patients (87.1%) were free of infection at a mean follow-up time of 85 months. No significant difference in infection control rate was observed between hip and knee PJIs (89.7% versus 85.7%). The mean postoperative Harris hip score was 76.1 points and HSS score was 78. 2 at the most recent assessment.

Single-stage revision with intra-articular antibiotic infusion can provide high antibiotic concentration in synovial fluid therefore overcome poor vascular supply and biofilm formation, which can be a viable option in treating PJI with PMFSR.

Previous work has demonstrated increased implant failure in patients with DDH compared to osteoarthritis with historic methods and implants. This study examines outcomes of modern total hip arthroplasty (THA) techniques using uncemented fixation and cross-linked PE (XLPE) bearings for DDH.

A consecutive series of 879 patients with DDH who underwent primary THA with uncemented components and a XLPE bearing at a single institution between 1999 and 2016 were identified. Mean age at index arthroplasty was 51 years, with 78% females. Mean follow-up was 8 years.

5- and 10-year survivorships free of revision were 98.4% and 98%, respectively. 5- and 10-year survivorships free of reoperation for any reason were 97% and 96%, respectively. Survivorship free of acetabular revision for aseptic loosening was 99.8% at 5 and 10 years, while survivorships free of femoral revision for aseptic loosening were 99.7% at 5 years and 99.5% at 10 years. Survivorship free of reoperation for PE damage (2 liner fractures, 2 rim damage from impingement) was 99.3% at 10 years. There were no revisions for bearing surface wear or osteolysis. 13% of patients experienced complications (4% dislocation, 3.3% wound complication rate). Ten-year survivorship free of reoperation for instability was 99.2%. 8 patients developed infection requiring operation (<1%). 100 patients had a prior pelvic osteotomy (11%), which did not increase rate of complications (p=0.22) or reoperations (p=0.51).

Fixation with modern uncemented implants has dramatically reduced implant loosening in patients with DDH, and the use of XLPE bearings has markedly reduced revision for PE wear/osteolysis in this young patient population, leading to dramatically improved mid/long-term survivorship compared to historic series.

Patients may be able to return to higher level activities following hip arthroplasty with modern techniques and prostheses, but the Oxford hip score, the standard PROM used by the NJS exhibits severe skew and kurtosis. The commonest score is 48/48. Most patients score above 40 preventing any discrimination between approaches or prostheses. We therefore sought both subjective and objective metrics which were relevant and valid without skew or high kurtosis in postoperative patients. The Metabolic Equivalent of Task (MET) reports energy usage in kcal/min burnt across a range of activities, condensed into a score of 0–25. A MET over 8 is considered ‘conditioning exercise’ tethered to life expectancy. A 2 point difference in average MET is considered a clinically relevant difference. Walking speed is a simple valid metric tethered to life expectancy, with a 0.1m/sec difference in walking speed equates to a clinically important difference.

Oxford Hip Score (OHS), and the MET were prospectively recorded in 221 primary hip arthroplasty procedures pre-operatively and at 1-year using a web based application. Pre and postoperative Gait analysis was undertaken on a subgroup of 34 patients, in comparison with age and sex matched controls.

Post-operatively, the OHS demonstrated significant skewed distributions with ceiling effects of 41% scoring 48/48. The MET was normally distributed around a mean of 10.3, with a standard deviation of 3.8 and no ceiling effect. Walking speed was normally distributed around a mean of 1.8m/sec, with a standard deviation was 0.15 m/sec

The MET is a simple patient reported score, which is normally distributed in patients following hip arthroplasty, around a mean of 10.3 with a standard deviation of 3.8. This valid activity metric correlates well with fast walking speed. This is also normally distributed with a standard deviation of over 0.1m/sec confirming low kurtosis. These simple measures have face validity: undertaking less active pastimes and being unable to keep up with other walkers are obviously inadvisable. The normal kurtosis of these metrics suggest that they may able to detect clinically relevant differences in outcome which are undetectable with commonly used PROMs. For surgeons developing less invasive approaches or using novel stems, these measures may detect clinically important improvements undetectable by the Oxford Hip Score.

First-time revision acetabular components have a 36% re-revision rate at 10 years in Australia, with subsequent revisions known to have even worse results. Acetabular component migration >1mm at two years following revision THA is a surrogate for long term loosening. This study aimed to measure the migration of porous tantalum components used at revision surgery and investigate the effect of achieving press-fit and/or three-point fixation within acetabular bone.

Between May 2011 and March 2018, 55 patients (56 hips; 30 female, 25 male) underwent acetabular revision THR with a porous tantalum component, with a post-operative CT scan to assess implant to host bone contact achieved and Radiostereometric Analysis (RSA) examinations on day 2, 3 months, 1 and 2 years. A porous tantalum component was used because the defects treated (Paprosky IIa:IIb:IIc:IIIa:IIIb; 2:6:8:22:18; 13 with pelvic discontinuity) were either deemed too large or in a position preventing screw fixation of an implant with low coefficient of friction. Press-fit and three-point fixation of the implant was assessed intra-operatively and on postoperative imaging.

Three-point acetabular fixation was achieved in 51 hips (92%), 34 (62%) of which were press-fit. The mean implant to host bone contact achieved was 36% (range 9–71%). The majority (52/56, 93%) of components demonstrated acceptable early stability. Four components migrated >1mm proximally at two years (1.1, 3.2, 3.6 and 16.4mm). Three of these were in hips with Paprosky IIIB defects, including 2 with pelvic discontinuity. Neither press-fit nor three-point fixation was achieved for these three components and the cup to host bone contact achieved was low (30, 32 and 59%).

The majority of porous tantalum components had acceptable stability at two years following revision surgery despite treating large acetabular defects and poor bone quality. Components without press-fit or three-point fixation were associated with unacceptable amounts of early migration.

Residual Legg-Calve-Perthes (LCP) deformities represent one of the most challenging disorders in hip reconstructive surgery. We assessed mid-term PROMs, radiographic correction, complications and survivorship of combined surgical dislocation (SD) and periacetabular osteotomy (PAO) for the treatment of complex LCP deformities.

A longitudinal cohort study was performed on 31 hips with complex LCP deformities undergoing combined SD/PAO. Treatment included femoral head reshaping, trochanteric advancement and relative neck lengthening, management of intra-articular lesions and PAO. Twenty-seven (87.1%) had minimum 5-year follow up. Average age was 19.8 years with 56% female and 44% having previous surgery.

At a mean 8.4 years, 85% (23/27) of the hips remain preserved (no conversion to THA). The survivorship estimates at 5 and 10 years were 93% and 85%, respectively. The median and interquartile range for mHHS increased from 64 [55–67] to 92 [70–97] (p<0.001), the WOMAC-pain improved from 60 [45–75] to 86 [75–100] (p= 0.001). An additional 19% (n=5) reported symptoms (mHHS <70) at final follow-up. UCLA activity score increased from a median of 8 [6–10] to 9 [7–10] (p=0.207). Structural correction included average improvements of acetabular inclination 15.3^o ± 7.6, LCEA 20.7° ± 10.8, ACEA 23.4° ± 16.3, and trochanteric height 18 mm ± 10 mm (all, p<0.001). Complications occurred in two (7%) patients including one deep and one superficial wound infection.

At intermediate follow-up of combined SD/PAO for complex LCP deformities, 85% of hips are preserved. This procedure provides reliable deformity correction, major pain relief, improved function and acceptable complication/failure rates.

The purpose of this study was to precisely measure the 10-year polyethylene wear rate of primary total hips using Radiostereometric analysis (RSA) comparing Oxidized Zirconium (OxZi) to cobalt chrome (CoCr) femoral heads articulating with highly cross-linked polyethylene (XLPE).

RSA was performed on 46 patients who underwent total hip arthroplasty − 23 who received OxZi femoral heads and 23 who received CoCr heads in combination with XLPE at a minimum of 10 years follow-up. All patients had identical THR systems implanted except for the femoral head utilized. The Centre Index method was utilised to assess total wear rates (from index surgery until final evaluation) using a dedicated RSA Software program (UmRSA Digital Measure v.2.2.1). In addition, the Martell technique was used to subtract head penetration occurring in the first 1–2 years (i.e. bedding-in phase) to allow calculation of the ‘steady state’ wear rates.

There were no significant differences in demographics (i.e age, BMI, gender) between the groups. The average time from surgery of the RSA examinations was 11.7 and 12.6 years for the CoCr and OxZi groups respectively. Using the Centre Index Method to calculate total head penetration, wear rates were slightly higher in the OxZi group (0.048 +/− 0.021mm/year) compared to the CoCr group (0.035 +/− 0.017mm/year) with no statistical difference between the groups (p= 0.02). After correction for the bedding-in period, there was no statistically significant difference in mean ‘steady-state’ wear rate between OxZi (0.031 +/− 0.021mm/year) and CoCr (0.024 +/− 0.019mm/year) at 10 year follow up (p= 0.24). A comparison of preoperative and postoperative SF12, HHS, and WOMAC scores showed no statistical difference between the groups.

RSA demonstrated the 10 year in-vivo wear rates of both bearing combinations to be well below the threshold for osteolysis. There was no significant difference between either the total or ‘steady-state’ wear rates of the OxZi and CoCr groups at 10 years.

Young patients are at increased risk of revision after primary THA (THA). The bearing surface may be of importance for the longevity of the joint.

We aimed to compare the risk of revision of primary stemmed cementless THA with MoM and CoC with metal-on-highly-crosslinked-polyethylene (MoXLP) bearings in patients between 20–54 years.

From NARA, we included 2,153 MoM, 4,120 CoC and 10,329 MoXLP THA operated between 1995 and 2017. Kaplan-Meier estimator was used for calculation of THA survivorship and Cox regression to estimate the hazard ratio (HR) of revision (95% CI) due to any and specific causes. MoXLP was reference.

The median follow-up was 10.3 years for MoM, 6.6 years for CoC and 4.8 years for MoXLP. 15 years postoperatively the Kaplan-Meier survival estimates were 80% (78–83%) for MoM, 92% (91–93%) for CoC and 94% (93–95%) for MoXLP. The 0–2, 2–7 and 7–15 years adjusted HRs of revision by any cause were 1.4 (0.9–2.4), 3.2 (2.1–5.1) and 3.9 (1.9–7.9) for MoM and 1.1 (0.8–1.4), 1.0 (0.7–1.3) and 2.5 (1.3–4.8) for CoC bearings. After 7–15 years follow-up, the unadjusted HR of revision due to aseptic loosening was 5.4 (1.2–24) for MoM and 4.2 (0.9–20) for CoC THA. MoM and CoC had a 7–15 year adjusted HR of revision due to ‘other’ causes of 4.8 (1.6–14) and 2.1 (0.8–5.8).

MoXLP bearings were associated with better survival than MoM and CoC bearings, mainly because of lower risk of revision due to aseptic loosening and ‘other’ causes.

The purpose of this randomized controlled trial was to evaluate serum metal ion levels in patients undergoing THA with either a standard or modular dual-mobility bearing.

Patients undergoing primary THA for osteoarthritis were randomized to receive either a modular dual-mobility or a standard polyethylene bearing. All patients received the same titanium acetabular and femoral component and a ceramic femoral head. Only patients without a prior history of metal implants in their body were eligible for inclusion, thus isolating serum metal ions to the prosthesis itself. Serum metal ion levels were drawn pre-operatively and at 1 year postoperatively. Power analysis determined that 40 patients (20 in each group) were needed to identify a clinically relevant difference in serum cobalt of 0.35 ng/ml (ppb) at 90% power assuming a pooled standard deviation of 0.31 ppb and alpha=0.05; an additional 30% were enrolled to account for potential dropouts.

53 patients were enrolled, with 22 patients in the modular dual-mobility group and 20 in the standard cohort with data available at one-year. No differences in the serum cobalt (0.17 ppb [range 0.07 to 0.50] vs. 0.19 ppb [range 0.07 to 0.62], p = 0.51) or chromium levels (0.19 ppb [range 0.05 to 0.56] vs. 0.16 ppb [range 0.05 to 0.61], p = 0.23) were identified.

At 1 year postoperatively, no differences in serum cobalt or chromium levels were identified with this design of a modular dual mobility bearing when compared to a standard polyethylene bearing.

To design osteoarthritis (OA) care based on prognosis, we need to identify individuals who are most likely of disease progression. We estimated survival time of the native hip and knee joint and evaluated what patient-related and OA disease-related factors associated with progression to joint replacement surgery.

We included 72,069 patients referred to first-line OA intervention (patient education and exercise) during 2008 and 2016 and registered in the Swedish quality register Better Management of Patients with Osteoarthritis (BOA). Kaplan–Meier survival analyses were used to estimate joint survival time. Hazard ratios (HR) with 95% confidence interval [CI] were calculated using multiple Cox regression.

The 5-year survival time of the native joint was 56% for hip OA and 80% for knee OA. Disease-related factors were more strongly associated with progression to joint replacement (e.g. willingness for surgery HR; hip 2.9 [95% CI, 2.7–3.1], knee 2.7 [2.6–2.9] and walking difficulties (HR; hip 2.2 [2.0–2.5], knee 1.9 [1.7–2.2]), than patient-related factors such socioeconomic factors (e.g. highest income quartile HR; hip 1.3 [1.2–1.3], knee 1.3 [1.2–1.4]) and comorbidities (e.g. ≥6 conditions HR; hip: 0.7 [0.6–0.7], knee; 1.1 [1.0–1.2]).

Patients with hip OA were more likely to undergo surgery and at an earlier time compared with those with knee OA. Progression was strongly influenced by factors associated with the OA disease, but other patient-related factors are important. However, a large proportion of patients with OA do not seem to require surgery, especially among those with knee OA.

Acetabular retroversion is a recognised cause of hip impingement. Pelvic tilt influences acetabular orientation and is known to change in different functional positions. While previously reported in patients with developmental dysplasia of the hip, positional changes in pelvic tilt have not been studied in patients with acetabular retroversion.

We retrospectively analysed supine and standing AP pelvic radiographs in 22 patients with preoperative radiographs and 47 with post-operative radiographs treated for symptomatic acetabular retroversion. Measurements were made for acetabular index (AI), lateral centre-edge angle (LCEA), crossover index, ischial spine sign, and posterior wall sign. The change in pelvic tilt angle was measured both by the Sacro-Femoral-Pubic (SFP) angle and the Pubic Symphysis to Sacro-iliac (PS-SI) Index.

In the supine position, the mean calculated pelvic tilt angle (by SFP) was 1.05° which changed on standing to a pelvic tilt of 8.64°. A significant increase in posterior pelvic tilt angle from supine to standing of 7.59° (SFP angle) and 5.89° (PS –SI index) was calculated (p<0.001;paired t-test). The mean pelvic tilt change of 6.51° measured on post-operative Xrays was not significantly different (p=.650). There was a good correlation in pelvic tilt change between measurements using SFP angle and PS-SI index (rho .901 in pre-op group, rho .815 in post-op group). Signs of retroversion were significantly reduced in standing x-rays compared to supine: Crossover index (0.16 vs 0.38; p<0.001) crossover sign (19/28 vs 28/28 hips; p<0.001), ischial spine sign (10/28 hips vs 26/28 hips; p<0.001) and posterior wall sign (12/28 vs 24/28 hips; p<0.001).

Posterior pelvic tilt increased from supine to standing in patients with symptomatic acetabular retroversion, in keeping with previous studies of pelvic tilt change in patients with hip dysplasia. The features of acetabular retroversion were much less evident on standing radiographs. The low pelvic tilt angle in the supine position is implicated in the appearance of acetabular retroversion in the supine position. Patients presenting with symptoms of hip impingement should be assessed by supine and standing pelvic radiographs so as not to miss signs of retroversion and to assist with optimising acetabular correction at the time of surgery.

Developmental dysplasia of the hip (DDH) is defined as abnormal, pathological relations between the elements of the hip joint, resulting from disorders of its development. Since 1984, periacetabular bernese osteotomy (PAO) has been a method of treating DDH. The aim of this study was to evaluate the results of the PAO in persistent deformity from childhood and primary late dysplasia in adolescents and adults.

Patients were divided into four groups: A - adolescent patients not operated of DDH in childhood, B – adolescent patient after a surgical treatment of DDH in childhood, C - adults with hip dysplasia not previously operated, D - control group. Radiological evaluation of standard AP view of hip joints was performed before and after the surgery and included parameters: Wiberg angle (CEA), femoral head cover (FHC), medialization, distalisation, the ilio-ischial angle.

Improvement in radiological parameters and statistical significance were achieved in all measurements in all patients. The greatest improvement was achieved in: CEA − 19˚ in Group B, Medialization − 3mm in Group C, Distalization − 6mm in Group B, FHC − 17% in Group B, Ilio-ischial angle − 5˚ in Group B.

The greatest correction of radiological parameters was obtained in children operated in childhood. Surgical treatment of DDH in childhood worsens the operating conditions in adolescents and adults due to scars, adhesions and altered bone anatomy but leaves the need for less deformity correction. The surgical treatment of DDH in childhood has a beneficial effect on the final outcome of the treatment of patients undergoing PAO surgery in adolescents and young adults.

This retrospective study was to investigate radiographic and clinical outcomes in treatment of hip instability in children and young adults undergoing periacetabular osteotomy (PAO) with or without femoral osteotomy.

19 patients (21 hips) with CP were treated with PAO with or without femoral osteotomy The mean age was 16.2 years old (7 to 28 years). Five patients (5 hips) received PAO, Six patients (7 hips) PAO with femoral derotation osteotomy, Eight patients (9 hips) PAO with varus derotational osteotomy (VDRO). Anteroposterior pelvic radiographs and CT were taken to assess the migration percentage (MP), lateral center-edge angle (LCEA), Sharp angle, femoral neck anteversion, neck-shaft angle. Gross Motor Function Classification System (GMFCS) was assessed pre- and post-surgery. Complications were recorded. The mean follow-up time was 41.2 months (range, 24 to 86 months).

All hips but one were pain free at final visit. The GMFCS improved by one level in 10 of 19 patients. MP improved from a mean of 76.6% to 18.6% at the final follow-up(p<0.001). The mean pre-operative LCEA and Sharp angle were −33.5 ? and 35 ? respectively, improved to 21.5 ? and 11.8 ? at the final follow-up (p < 0.001). There were six patients (7 hips) had re-subluxation at latest follow-up. Nervus cutaneus femoris lateralis was impaired in four patients after surgery. There was no re-dislocation, AVN, or infections in this group.

Satisfactory clinical and radiologic results can be obtained by PAO with or without femoral osteotomy minor complications.

With the approval of our institute, we reviewed all the robot-assisted hip revision during October 2019 and August 2021. MAKO joint arthroplasty system was used to perform the hip revision surgery.

Seventy-one robot-assisted hip revision cases were included. Cup revisions were carried out in 68 patients while stem revisions were also carried out in 68 patients. Three types of registration techniques (extra acetabular bone surface based, liner based, metal shell based or cage surface based) on the acetabular side. The extra acetabular bone surface was the commonest used for registration (48/70, 68.6%, mean accuracy 0.37mm), followed by liner surface (11/70, 15.7%, mean accuracy 0.36mm), acetabulum cup (10/70, 14.3%, mean accuracy 0.37mm), and cage surface (1/70, 1.4%, accuracy 0.40mm). We succeeded cup registration and robotic arm guided cup insertion in all the cases. The average cup inclination and anteversion after revision were 40.87°±4.39° and 13.87°±4.24°, respectively. Cups in 62 cases (62/68, 91.2%) were within the Lewinnek safe zone while in 55 cases (55/68, 80.9%) were within the Callanan safe zone.

The Mako robot-assisted system could bring favorable cup reconstruction in hip revision with acceptable surgical time and blood loss. Accurate registration could be achieved by different methods.

Imageless computer navigation systems in total hip arthroplasty (THA) improve acetabular cup position, thereby reducing the risk of revision surgery for all causes as well as dislocation. We aimed to evaluate the registration accuracy of 3 alternate registration planes.

A prospective, observational study was conducted with 45 THA in the supine position using two imageless navigation systems and 3 registration planes. Patient position was registered sequentially using an optical system (Stryker OrthoMap) and an inertial sensor-based system (Navbit Sprint) with 3 planes of reference: (Plane 1) an anatomical plane using the anterior superior iliac spines (ASISs) and the pubic symphysis; (Plane 2) a functional plane parallel to the line between the ASISs and the table plane; and, (Plane 3) a functional plane that was perpendicular to the gravity vector and aligned with the longitudinal axis of the patient. The 3 measurements of acetabular cup inclination and anteversion were compared with the measurements from postoperative computed tomography (CT) scans.

For inclination, the mean absolute error was significantly lower for Plane 3 (1.80°) than for Plane 2 (2.74°), p = .038 and was lower for both functional planes than for the anatomical plane (3.75°), p < .001.

For anteversion, the mean absolute error was significantly lower for Plane 3 (2.00°) than for Plane 2 (3.69°), p = .004 and was lower for both functional planes than for the anatomical plane (8.58°), p < .001.

Patient registration using functional planes more accurately measured the acetabular cup position than registration using anatomic planes.

To compare complications, survivorship and results in 2 groups of Furlong-HAP Active, one with ceramic-ceramic and the other with metal-XLPE friction pair

Prospective, non-randomized, comparison of 2 series of JRI uncemented prosthesis, implanted with identical protocol by 1 surgeon in 1 hospital from 2006 to 2014. Friction pair was ceramic (Biolox Forte or Delta) in 35 patients of 53.7+/−10.6 years (25–69) (21 males, 60%), and CrCo-XLPE in 65 cases of 69.0+/−8.9 years (42–81) (36 males, 55%); there were significant differences in age (p<0.00001) but not in sex (p=0.6565).

Head diameter: Ce-Ce with 19 of 28mm, 9 of 32 and 7 of 36mm; Me-PE with 63 of 28mm, 1 of 32 and 1 of 36. Follow-up averaged 10.5+/−3.1 years (1–15) in ceramic and 9.8+/−3.8 years (2–15) in XLPE group. Pearson, Fisher, Kolmogorov-Smirnov, Student, Mann-Whitney, calculated with the informatic tools Microsoft Excel 2007 and https://www.socscistatistics.com/tests/.

Complications in ceramic joints: 2 late infections (Fisher exact test=0.6101) (1 DAIR, 1 one-stage exchange); 1 dislocation (Fisher exact test=0.2549) (closed reduction); 1 Vancouver C fracture (ORIF) (Fisher exact test=0.6548). Complications in Me-XLPE joints: 2 late infections (Fisher=0.6101) (1 DAIR, 1 two-stage exchange); 7 dislocations (Fisher=0.2549) (2 early, open reduction) (5 late: 3 closed reduction, 1 cup revision, 1 constrained cup); 4 Vancouver B fractures (Fisher=0.6548) (2 intraoperative, cerclages; 2 late, exchange).

Final follow-up: Harris Hip Score averaged 93.2+/−13.7 (23–100) in ceramic and 94.3+/−8.7 (65–100) in XLPE joints (p=0.64552).

Wear: 0.06+/−0.38mm (0–1.5) in ceramic and 0.16+/−0.5mm (0–2) in Me-PE THAs (p=0.30302).

Osteolysis in Charnley-De Lee zones: 8 zones (6 patients) (17%) in ceramic cups, 25 zones (15 patients) (23%) in XLPE cups (p=0.980127).

Survivorship without any surgery or closed reduction after 15 years: 91.0% in ceramic joints, 83.8% in Me-XLPE joints.

Survivorship without component exchange after 15 years: 93.9% in ceramic joints, 93.6% in Me-XLPE joints.

At least after 10 years follow-up of Furlong-HAP Active, metal-XLPE and ceramic-ceramic joints present no significant differences in complications, clinical score, wear, acetabular osteolysis, or survivorship without component exchange. On the contrary, survivorship without any surgery or closed reduction is different because of the high rate of dislocation in 28mm metal-poly joints.

Fracture risks are the most common argument against the use of Ceramic on ceramic (CoC) hip implants. Question: is ceramic material at risk in case of severe local trauma?

Over a long period, we tried to identify patients with a CoC prosthesis (Ceraver Osteal°)who did sustain a trauma. This was conducted in three different institutions.

Eleven patients were found: 9 males and 2 females aged 17 to 70 years at time of index surgery. Accident occurred 6 months to 15 years after index: one car accident, five motorcycle accident, five significant trauma after a fall, including one ski board accident. Consequences of these trauma were: six fractures of the acetabulum with socket loosening in 4 that needed revision, two femoral shaft fracture, one orifed and one stem exchanged, one traumatic hip dislocation associated to loosening of the socket revised at 10 years, and one traumatic loosening of the socket. Ten had no consequence on ceramic integrity. One experienced a fracture of the patella from a dashboard trauma, a liner shipping was discovered during socket revision 2 years later. This is the only case of possible relation between trauma and ceramic fracture. In a more recent longitudinal study on 1856 CoC prosthesis performed from 2010 to 2021, 29 severe traumas were identified with no consequence on Ceramic material.

From this limited case study, it can be assumed that Pure Alumina Ceramic well designed and manufactured, will not break after a significant trauma.

Adverse spinopelvic mobility (SPM) has been shown to increase risk of dislocation of primary total hip arthroplasty (THA). In patients undergoing THA, prevalence of adverse SPM has been shown to be as high as 41%. Stiff lumbar spine, large posterior standing pelvic tilt and severe sagittal spinal deformity have been identified as risk factors for increased hip instability. Dislocation rates for dual mobility articulations have been reported to be 0% to 1.1%. The aim of this study was to determine the early survivorship from the Australian National Joint Replacement Registry (AOANJRR) of patients with adverse SPM who received a dual mobility articulation.

A multicentre study was performed using data from 229 patients undergoing primary THA, enrolled consecutively. All the patients who had one or more adverse spine or pelvic mobility parameters had a dual mobility articulation inserted at the time of their surgery. Average age was 76 (22 to 93) years and 63% were female. At a mean of 2.1 (1 – 3.3) years post-op, the AOANJRR was analysed for follow-up. Reasons for revision and types of revision were identified.

The AOANJRR reported two revisions. One due to infection and the second due to femoral component loosening. No revisions for dislocation were reported. One patient died with the prosthesis in situ. Kaplan Meier survival was 99.3% (CI 98.3% − 100%) at 2 years.

DM bearings reduce the risk of dislocation of primary THA in patients with adverse spine and pelvic mobility.

Known risk factors for early periprosthetic femur fracture (PFF) following total hip arthroplasty (THA) include poor bone quality, surgical approach and cementless implants. The association between femoral component size and alignment and the risk of early PFF is not well described. We evaluated radiographic parameters of femoral component sizing and alignment as risk factors for early PFF.

From 16,065 primary cementless THA, we identified 66 cases (0.41%) of early PFF (<90 days from index THA) at a single institution between 2016–2020. The stem was unstable and revised in all cases. We matched 60 cases of early PFFs (2:1) to 120 controls based on femoral component model, offset, surgical approach, age, BMI, and sex. Mean age was 67 years; 60% were female. Radiographic assessment of preoperative bone morphology and postoperative femoral component parameters including stem alignment, metaphyseal fill, and medial congruence with the calcar. A multivariable logistic regression was built to identify radiographic risk factors associated with early PPF.

Markers of poor preoperative bone quality including canal calcar ratio (p=0.003), canal flare index (p<0.001), anteroposterior canal bone ratio (CBR) (p<0.001) and lateral CBR (p<0.001) were statistically associated with PFF. Valgus alignment (23% versus 12%) (p<0.001) was more prevalent in the PFF group compared to controls, as well as varus alignment of the implant (57% versus 43%). Distance between the medial aspect of the implant and the calcar was greater in cases of PFF (2.5 mm versus 1.4 mm) (p<0.001). Multivariate analysis demonstrated that valgus implant alignment (Odds Ratio (OR) 5) and medial implant-calcar incongruity (OR 2) increased the risk of early PFF.

Medial implant-calcar incongruity and valgus alignment of the femoral component were risk factors for early PFF following cementless THA after controlling for age, sex, BMI, approach, proximal femoral morphology, and implant design.

Special acetabular polyethylene (PE) liners are intended to increase the stability of the artificial hip joint, yet registry studies on them are limited. The pupose of this study was to investigate differences in revision rates for mechanical complications in primary cementless total hip arthroplasty (THA) with standard and special PE acetabular liners in patients with ostheoarthritis.

Data from the German Arthroplasty Registry (EPRD) between 2012 until 2020 were analysed. Patients with diagnosed ostheoarthritis of the hip without relevant prior surgeries, who received a primary cementless THA with a ceramic/PE bearing articulation were included. Cumulative incidences of revision for mechanical complications for Standard and 4 special PE liners (Lipped, Increased Offset, Angulated, Angulated|Increased Offset) were determined using the Kaplan-Meier Estimator. Confounding factors were investigated with a Cox proportional-hazards model.

In total 151.104 cases were included. 7-year unadjusted revision-free survival for mechanical complications compared to Standard liners (97.7%) was lower for Angulated (97.4%), Lipped (97.2%) and Angulated|Increased Offset liners (94.7%), but higher for Increased Offset liners (98.1%). Risk of revision for mechanical complications was not significantly different between Standard, Lipped and Angulated liners. Increased Offset liners (HR=0.68; 95% CI=0.5–0.92) reduced, while Angulated|Increased Offset liners (HR= 1.81; 95% CI=1.38–2.36) increased the risk. Higher age at admission and an Elixhauser comorbidity index greater zero increased the risk, whereas a larger liner share slightly reduced the risk.

Only the use of Increased Offset liners reduced the risk of revision for mechanical complications compared to Standard liners — other special liners did not.

To compare the incidence of Bone Cement Implantation Syndrome (BCIS), perioperative thromboembolic events and mortality in patients with a femoral neck fracture (FNF) treated with a hybrid total hip arthroplasty (THA) without intraoperative unfractioned heparin (UFH) (control) versus a group of patients who received intraoperative UFH before femoral cementation.

We retrospectively reviewed 273 patients who underwent hybrid THA due to a FNF between 2015 and 2020. We compared a group of 139 patients without intraoperative administration of UFH (group A) with 134 patients who underwent THA with intraoperative administration of 10 UI/kg UFH (group B). UFH indication was dependent on surgeon´s preference. We assessed the advent of BCIS and 30-day thromboembolic events, as well as 90-day and 1-year mortality.

BCIS was observed in 51 cases (18%), defined as Grade 1 (O2% < 94% or fall in systolic blood pressure of 20% to 40%) in 37 cases (13%) and Grade 2 (O2% < 88% or fall in systolic blood pressure of > 40%) in 14 cases (5%). Forty-seven BCIS (35%) were observed in the group that received UFH and 4 BCIS (3%) in the control group (p <0.001). Multivariate regression model showed that intraoperative UFH (OR=18, CI95% 6–52) and consumption of oral anticoagulants (OR=3.3, CI95% 1–10) had an increased risk of developing BCIS. Five patients developed a pulmonary embolism in the UFH group while 2 patients presented this complication in the non UFH group (p=0.231). Mortality was 1% for both groups at 90 days PO (p= 0.98), 2% at 1 year for group A and 3% for group B (p =0.38).

BCIS in our series was 18%. We found a paradoxically 17-fold significant increase of BCIS with the use of UFH. Heparin did not prevent BCIS, thromboembolic events and mortality in this group of patients.

A growing number of recent investigations on the human genome, gut microbiome, and proteomics suggests that the loss of mucosal barrier function, particularly in the gastrointestinal tract, may substantially affect antigen trafficking, ultimately influencing the close bidirectional interaction between the gut microbiome and the immune system. This cross-talk is highly influential in shaping the host immune system and ultimately clinical infections. The hypothesis of the current study was that a change in microbiome and/or breach in GI epithelial barrier could be partially responsible for development of periprosthetic joint infections (PJI).

Multiple biomarkers of gut barrier disruption were tested in parallel in plasma samples collected as part of a prospective cohort study of patients undergoing revision arthroplasty for aseptic failures or PJI (As defined by the 2018 ICM criteria). All blood samples were collected before any antibiotic was administered. Samples were tested for Zonulin, soluble CD14 (sCD14), and lipopolysaccharide (LPS) using commercially available enzyme-linked immunosorbent assays. Statistical analysis consisted of descriptive statistics, Mann-Whitney t-test, and Kruskal-Wallis test.

A total of 134 patients were consented and included in the study. 44 were classified as PJI (30 chronic and 14 acute), and 90 as aseptic failures (26 primaries and 64 aseptic revisions). Both Zonulin and sCD14, but not LPS, were found to be significantly increased in the PJI group compared to non-infected cases (p<0.001; p=0.003). Higher levels of Zonulin were found in acute infections compared to chronic PJI (p=0.005

This prospective ongoing study reveals a possible link between gut permeability and the ‘gut-immune-joint axis’ in PJI. If this association continues to be born out with larger cohort recruitment and more in-depth analysis, it would have an immense implication in managing patients with PJI. In addition to administering antimicrobials, patients with PJI and other orthopedic infections may require gastrointestinal modulators such as pro and prebiotics.

Recent case reports have described V40 taper failure with clinically relevant adverse reaction to metal debris (ARMD). The real incidence of V40 taper damage and potential consequences are currently unclear, however. Aim of this study is therefore, to evaluate the long-term incidence of pseudotumors in a consecutive series of THA with V40 taper and identify potential influencing factors.

From 2006 to 2007 a total number of 120 patients (127 hips) received either an uncemented (Accolade©) or cemented hip stem (ABGII©), both with V40 taper (Stryker© Mahwah, New Jersey, USA). They all were combined with 36 mm Vitallium (CoCrMo) heads and uncemented cups (Trident©) with XLPE inlays. 11,2 +/− 0,5 years post-op 82 patients with 87 hips (mean age 74 years, 58 % female) underwent clinical (PROMs) and radiographic evaluation. In 71 patients (75 hips) MARS- MRI of the hip was performed. 38 patients were lost to follow-up. In 81 patients (86 hips) chrome and cobalt levels were determined.

MRI-investigation revealed 20 pseudotumors (26%) and 18 of them had a diameter of >2cm. Patients with pseudotumors had significant higher median cobalt ion levels compared to those without (2,85 μg/l vs. 1,32 μg/l; p=0,022) and a significant correlation between pseudotumors and cobalt levels was found. Radiographic osteolysis was associated with pseudotumors as well (p= 0,014). Neither approach, BMI, gender, age, type of stem, head length, inclination nor heterotope ossification showed a significant correlation to pseudotumor occurrence.

Due to the high incidence of local ARMD in in asymptomatic patients with V40 taper and metal heads we recommend regular post-operative follow-up investigations including routine metal ion screening and consecutive MRI investigation upon elevation.

We designed a study to evaluate whether (1) there were differences in PROMs between different reasons for revision THA at baseline, (2) there was a different interaction effect for revision THA for all PROMs, and (3) complication and re-revision rates differ between reason for revision THA.

Prospective cohort of 647 patients undergoing rTHA, with a minimum of 2 years FU. The reason for revision were classified as infection, aseptic loosening, dislocation, structural failure and painful THA with uncommon causes. PROMs (EQ-5D score, Oxford hip score (OHS), VAS pain, complication and failure rates were compared between different groups.

Patients with different reason for revision had improvement of PROMs’ over time. Preoperatively, patients revised due to infection and aseptic loosening had poorer OHS and EQ-5D than patients with other reason for revision. Pain scores at baseline were highest in patients revised due to dislocation. Infection and aseptic loosening groups also showed a significant interaction effect over time in both OHS and EQ-5D. No PROMs significant differences between groups were observed 2 years postoperatively. Overall complications, and re-revision rates were 35.4 and 9.7% respectively.

The reason for revision THA did not associate with clinical outcomes. Good outcomes were reached regardless of the reason for revision, as patients with the poorest pre-operative scores had the best improvement in PROMs over time. Complication and re-operation rates were relatively high, in line with previous reports, but did not differ between different reasons for revision THA.

Until today it is unknown whether preservation of the joint capsule positively affects patient reported outcome (PROs) in DAA-THA. A recent RCT found no clinical difference at 1 year. Since 2015 we preserve the capsule suture it at the end. We here evaluate whether this change had any effect on PROs and revisions, 2 years post-operatively.

Two subsequent cohorts operated by the senior author were compared. The capsule was resected in the first cohort (January 2012 – December 2014) and preserved in the second cohort (July 2015 – December 2017). No other technical changes have been introduced between the two cohorts. Patient demographics, Charlson Comorbidity Index (CCI), and surgical data were collected from our clinical information system. 2-years PROs questionnaires (OHS, COMI Hip) were obtained. Data was analyzed with generalized multiple regression analysis.

430 and 450 patients were included in the resected and preserved cohorts, respectively. Demographics, CCI surgical time and length of stay were equal in both groups. Blood loss was less in the preserved cohort (p<.05). Four patients had a revision (1 vs 3, n.s.). Once corrected for demographics, capsule preservation had significant worse PROs: +0.24 COMI (p<.001) and −1.6 OHS points (p<.05), however, effects were much smaller than the minimal clinically important difference (0.95 and 5 respectively). The date of surgery (i.e. surgeon's age) was not a significant factor.

In this large retrospective study, we observed statistically significant, but probably clinically not relevant, worse PROs with capsule preservation. It might be speculated that the not resected hypertrophied capsule could have caused this difference.

Femoral head necrosis in the context of high impact gymnastics of young adolescents is rare but seems a more serious complication compared to a Perthes like necrosis.

Between 2017 and 2019, three young females aged from12 to 14 years were referred due incapacitating hip pain and severe collapsing femoral head necrosis. The indication of hip preserving surgery was based on the extent of the necrosis, presence of a vital lateral pillar and joint subluxation.

In one of our 3 cases total head involvement made THR necessary, which was performed elsewhere. In the remaining 2 cases, head reduction osteotomy plus periacetabular osteotomy led to a good and a fair result.

Repetitive impact between the main supplying vessels on the posterolateral femoral neck and the posterior acetabular wall in hyperextension/ external rotation could be the cause of severe femoral head necrosis in three adolescent female gymnasts we are reporting on. Supra-selective angiography or sonography may be helpful to improve indication. Targeted adaptation of training methods should be discussed. Due to the severe vascular insult, results have to be considered moderate.

The purpose of this study is to understand the lived experience of mature patients who undergo a periacetabular osteotomy (PAO), a major surgical procedure that treats symptomatic hip dysplasia by realigning the acetabulum. Our aim was to better understand how the PAO impacted the lives of the patients and their families, with a long-term goal of improving the experience.

We utilized a phenomenological approach with in-depth, semi-structured interviews to investigate the experience of seven women, ages 25–40, who underwent a PAO. A modified intensity sampling method coupled with criterion sampling was used. Inclusion criteria included raising at least one child and being in a committed relationship with a partner.

Analysis of interview transcripts revealed eight themes, each of which falls into one of three chronological periods.

From the start of dysplasia symptoms until meeting the PAO surgeon: (1) frustration with symptoms disrupting daily activities, (2) discouragement from misdiagnoses and lack of explanation for symptoms, and (3) fear of the PAO operation.

During the PAO decision-making process: (1) the importance of education regarding the PAO procedure and full understanding of its purpose, and (2) the utility of social media to learn from past PAO patients in order to feel more confident about the decision to undergo PAO.

Post-operation through recovery: (1) feelings of helplessness, isolation and difficulty asking for help, (2) relying heavily on family and/or close friends for assistance, and (3) desire for more support and communication from the healthcare team.

Our findings suggest that the psychosocial burden of PAO surgery is great, with major impact on the patient and family. Many important issues lie outside the scope of what healthcare teams currently address.

This study aimed to analyse the incidence, the operative findings and outcomes of hip arthroscopy after periacetabular osteotomy (PAO).

We conducted a retrospective study of prospective collected data to report the operative findings and outcomes of hip arthroscopy for recurrent pain following PAO for acetabular dysplasia. Demographic data, radiographic and arthroscopic findings were analysed. Pre- and post-operative patient reported outcome measures (PROMs) were collected.

Of 184 PAO patients, 15 hips in 15 patients (8.2%) underwent post-PAO hip arthroscopy with 2 males and 13 females at a mean time of 3.9 ±2.9(0.3–10) years. Hip arthroscopy findings included labral tears (15 hips, 100%), chondral damage (11 hips, 73%) with one Beck 1, two Beck 2, four Beck 4, and four Beck 5 damage. There were 8 (53%) isolated labral debridement, 7 (47%) labral repair, and 2 (13%) adhesiolysis. A femoral osteochondroplasty was performed in 4 (27%) hips. Four hips (27%) were finally converted to total hip replacement at a mean delay of 2.3 ±1.4 (0.7–3.2) years post hip arthroscopy and these 4 patients were significantly older than those who were not (p=0.02). There were no significant differences in PROMs pre and post hip scope.

8.2% of patients undergoing a PAO required a hip scope for persistent hip pain. Common post-PAO hip arthroscopy findings included labral tears, chondral changes and femoroacetabular impingement. 27% of patients finally underwent conversion to total hip replacement at a mean follow-up of 4.5 years post hip scope.

Reported incidence of blood transfusion following primary and revision total hip arthroplasty (pTHA, rTHA) has decreased considerably compared to historical rates. However, it is not known if further adoption of techniques to limit transfusions has resulted in further reduction on a large scale. The purpose of this study was to assess recent trends in blood transfusions and contemporary risk factors for transfusions using a large, national database.

The American College of Surgeons National Surgical Quality Improvement Program was queried to identify patients undergoing pTHA and rTHA between 2011 to 2019. pTHA for fracture, infection, tumor, and bilateral procedures were excluded. Only aseptic rTHA were included. Annual incidence of transfusions and proportion of patients with optimized preoperative hematocrit (HCT) (defined as ≥33%) were assessed. Risk factors for transfusion were evaluated with 2018 and 2019 data using multivariate analyses.

234,352 pTHA and 16,322 rTHA were included. Transfusion following pTHA decreased from 21.4% in 2011 to 2.5% in 2019 and from 33.5% in 2011 to 12.0% in 2019 for rTHA (p<0.0001). Patients with optimized HCT increased for pTHA (96.7% in 2011 vs 98.1% in 2019, p<0.0001) and did not change for rTHA (91.5% in 2011 vs 91.6% in 2019, p=0.27). Decreased HCT was most strongly associated with transfusions, with each three-point change corresponding to odds ratio of 1.90 and 1.78 for pTHA and rTHA, respectively. Increased age, female sex, history of bleeding disorders or preoperative transfusion, ASA score ≥3, non-spinal anesthesia, and longer operative times were also associated with increased odds for transfusion.

Incidence of blood transfusion has continued to decrease following pTHA and rTHA. Despite care improvements, transfusions still occur in certain high-risk patients. While transfusion in pTHA may have reached the lower asymptote, further reduction in rTHA may be possible through further improvements in preoperative optimization and surgical technique.

The goal of the study was to describe the features of the aseptic loosening of the cup in CoC THR and to determine factors that affect the time to revision.

It is a retrospective study including all patients who had a revision of CoC THR for aseptic failure fixation of the cup, between 2007 and 2017. 55 patients (27 women, 28 men) (56 hips) were included in the study. Eight hips (13 %) had also a stem exchange. At the primary T HR, the mean age of the patients was 47.9 years (17–72), 28 press fit cups had screws, the mean diameter of the cup was 51.2 mm (46–62) and the mean inclination was 52° (37–67). Clinical and radiological data were retrospectively recorded by an observer different to the initial operators.

The mean age of the patients at the revision was 55.4 years (26–84). The mean time to revision was 90.1 months (14–240), and was significantly greater in patients aged less than 52 years, in cups without screws and with a 28mm head. The trend curve of the time to cup revision showed a bimodal distribution at three and ten years. 20 cups had migrated (33%). Bone loss was rated type 1 in 41 hips (73.0%), type 2 in 12 hips and type 3 in three hips). The mean diameter of the new cup was 52.3 mm (46–64). It was inferior to that of the initial cup in 26 hips (46.4%). 31 cups were impacted (55.5%) and 25 needed to be cemented (45.5%). No macroscopic wear was detected on the ceramic implant.

Aseptic loosening of the cup in CoC THA does not appear to increase over time, supporting the fact that the failure is unrelated to wear and is not due to a biological mechanism. The occurrence of two peaks of frequency over time may suggest that different mechanisms occur.

To date there is no medical treatment alternative to surgery for osteolysis after THA. In this proof-of-concept clinical trial we examined the effect of a human monoclonal antibody against osteoclasts versus placebo on osteolytic lesion activity in patients undergoing revision surgery.

Patients scheduled for revision for symptomatic osteolysis were randomised (1:1) to receive either denosumab 60mg or placebo subcutaneously eight weeks prior to operation. At surgery, biopsies from the osteolytic membrane-bone interface were taken for histomorphometric analysis of osteoclast number. Secondary outcome measures included systemic bone turnover markers.

22 subjects completed the study (10 denosumab). The denosumab group had 83% (−63 to −97), P=0.011 fewer osteoclasts at osteolytic lesion sites, 87% lower osteoclast surface (−65 to −95, P=0.009), and 72% lower eroded surface (−35 to −93, P=0.020) versus the placebo group. At surgery, serum CTX-I, TRAP5b and PINP were 80% (−65 to −95, p<0.001), 57% (−40 to −90, p<0.001), and 44% (−41 to −65, p<0.001) lower in the denosumab versus placebo groups, respectively. The rate of adverse events (denosumab 6, placebo 7) were similar between groups (P>0.05).

These data provide a biological basis for a definitive clinical trial using pain, function and prosthesis survival as the study endpoints. As osteolysis/ aseptic loosening is the leading cause of prosthesis failure world-wide, the establishment of a non-surgical solution would reduce patient suffering and dramatically reducing the cost to healthcare economies.

To estimate the clinical and economic burden of primary total hip arthroplasty (THA) dislocation in England.

Retrospective propensity score-matched evaluation of patients with and without dislocation following primary THA using the UK Clinical Practice Research Datalink linked and Hospital Episode Statistics datasets with a 2-year follow-up.

13,044 patients with total hip replacements met the inclusion criteria (mean age 69.2, 60.9% female) of which 154 (1.18%) suffered at least one postoperative hip dislocation. The mean number of dislocations per patient was 1.44 with a maximum of 4. Approximately one-third of the patients with dislocation (32.5%) had more than one dislocation. Among patients with a hip dislocation 148 patients (96.7%) had at least one closed reduction and 20 patients (13.1%) had revision surgery. Two-year median direct medical costs were £14,748 (95% confidence interval [CI] £12,028 to £20,638) higher with vs. without dislocation (+227%). On average, patients with a dislocation had significantly greater healthcare resource utilization and significantly less improvement in EuroQol-5D (EQ-5D) index (0.24 vs. 0.45; p<0.001) and Visual Analogue Scale (VAS) (1.58 vs. 11.23; p=0.010) scores and Oxford Hip Scores (13.02 vs. 21.98; p<0.001).

This is the first study to estimate the economic burden of dislocation in the UK throughout the entire patient pathway. Dislocation following total hip replacement is a costly complication, both in terms of economic costs and to the functional quality of life of the patient. Efforts to reduce the risks of dislocation should remain at the forefront of hip research.

This study reports the ten-year outcomes of a three-arm, multicentre randomised controlled trial comparing Cobalt-Chrome (CoCr) and Oxidised Zirconium (OxZr) femoral heads with ultra-high molecular weight polyethylene (UHMWPE) versus highly cross-linked polyethylene (XLPE) liners in total hip arthroplasty (THA).

Patients undergoing THA from four institutions were prospectively randomised into three groups. Group A received a CoCr femoral head and XLPE liner; Group B received an OxZr femoral head and XLPE liner; and Group C received an OxZr femoral head and UHMWPE liner. The outcomes of 262 study patients were analysed at ten years follow-up.

At ten years, increased linear wear rates were recorded in group C compared to group A (0.133 ± 0.21 mm/yr vs 0.031 ± 0.07 mm/yr respectively, p<0.001) and group B (0.133 ± 0.21 mm/yr vs 0.022 ± 0.05 mm/yr respectively, p<0.001). Patients in group C had increased risk of osteolysis and aseptic loosening requiring revision surgery compared with group A (7/133 vs 0/133 respectively, p=0.007) and group B (7/133 vs 0/135 respectively, p=0.007). There was a non- significant trend towards increased liner wear rates in group A compared to group B (0.031 ± 0.07 mm/yr vs 0.022 ± 0.05 mm/yr respectively, p=0.128). All three groups were statistically comparable preoperatively and at ten years follow-up from a clinical score perspective.

The use of UHMWPE was associated with progressively increased annual liner wear rates. At ten years follow-up, this translated to an increased incidence of osteolysis and aseptic loosening requiring revision, compared with XLPE. Femoral heads composed of OxZr were associated with a non-significant trend towards reduced wear rates compared to CoCr, but this did not translate to any differences in osteolysis, functional outcomes, or revision surgery between the two treatments groups.

The clinical success of THA is accepted, however wide variation in implant usage and outcomes is reported across the world. The Getting It Right First Time initiative in the UK has recommended increased use of cemented constructs in patients over 70. A clear clinical directive has been proposed aiming to reduce revision rates, improve outcomes and increase cost effectiveness.

This study compares the outcomes of cemented, hybrid and cementless THA from a high-volume single center at long-term follow-up.

A prospective database identified 1,699 cemented, 5,782 hybrid and 2,631 cementless THAs. Mean follow-up was 8.1 years, 5.3 years and 6.3 years respectively. Primary endpoint was revision for any reason.

47 (1.79%) cemented, 93 (1.60%) hybrid and 39 (1.48%) cementless THAs underwent revision. The difference in overall revision rate was statistically significant (P=0.002). Mean time to revision was 4.5 years in the cemented group, 2.1 years in the hybrid group and 2.6 years in the cementless group.

1 year survivorship was 99.2% in the cemented group, 99.0% in the hybrid group and 98.9% in the cementless group. 3 year survivorship was 98.6% in the cemented group, 98.8% in the hybrid group and 98.9% in the cementless group. At 10 years it was 97.0%, 97.6% and 97.9% respectively. (Difference not statistically significant (p=0.09). Of relevance cemented fixation showed the lowest 10-year survivorship in patients over 70, over 75 and over 80. (not statistically significant P=0.5, 0.6 and 0.47 respectively).

In a high-volume center, excellent outcomes were achieved at 10 years with all three constructs. Cemented THA had the lowest survivorship compared to hybrid, then cementless fixation. Cemented fixation did not outperform cementless fixation in any age group. Surgeons should monitor their outcomes. Use of a philosophy that works best in their own hands should be supported.

We evaluated an anatomical uncemented stem, SP-CL, (Static Physiologicus – CementLess) designed to facilitate insertion and to avoid stress concentration at solitary contact points in a randomized controlled trial, with use of the Corail stem as control. The SPÅ-Cl stem has been on the market since 2014 but is still not well documented.

79 patients (80 hips) were primarily recruited and 71 patients (72 hips, 36 SP-CL, 36 Corail) attended the last follow up at 2 years. The clinical evaluation included several types of PROMs with Oxford Hip Score (OHS) as primary outcome. In addition, repeated measurements of stem migration, changes in bone mineral density and development of radiolucencies were studied with RSA, DXA and conventional radiography.

At two years the Oxford Hip Score did not differ between the SP-CL and Corail stem (estimated mean difference: −0.70 (95% CI: −4.28 – 2.89). In both groups Oxford hip score had almost doubled at 3 months, continued to increase up to 6 months and was about equal at 2 years (SP-CL; median 46 (17–48), Corail; median 47 (19–48)). At 2 years the SP-CL stems showed a median distal migration of −0.23 (−5.2 – 0.1) and the Corail stems of − 0.11 (−4.4 – 0.4). The SP-CL stems showed slightly more loss of bone mineral density in Gruen region 7 (p = 0.003).

We found no difference in clinical results with use of either of the two stems. Bone mineral density loss tended to be higher with use of the SP-CL stem and the early subsidence tended to be more pronounced, which turned out to be compatible with about the same stem stability reached between 1 and 2 years. As a next step we think that the SP-CL stem should be studied in a multi-center setting, before accepted for general use.

The increasing number of total hip arthroplasty (THA) used in young patients will inevitably lead to more revision procedures at younger ages, especially since the outcome of primary THA in young patients is already inferior compared to older patients. However, these data are lacking in literature. The aim of this study was to determine the survival of both acetabular and femoral components placed during primary and revision hip arthroplasty in patients under 55 years using Dutch Arthroplasty Register (LROI) data.

All primary THA registered in the LROI between 2007–2018 in patients under 55 years were selected (n=25,682). Subsequent cup- and stem revision procedures were included. Kaplan-Meier survival analyses were used to estimate the survival probability of primary and revised cup- and stem components.

Mean follow-up of primary cups and stems was 5.8 years (SD 3.2) and 5.9 years (SD 3.2), respectively. In total, 659 cup revision procedures and 532 stem revision procedures were registered. Most common reason for cup revision was acetabular loosening (n=163), most common reason for stem revision was femoral loosening (n=202). Primary cup survival for any reason at 10 years follow-up was 96.1% (95%CI: 95.7–96.4). For primary stems, 10 year survival for any reason was 97.1% (95%CI: 96.7–97.3). Mean follow-up of all revision procedures was 4.1 years (SD 2.9). Out of 659 cup revisions, 113 cup re-revisions were registered. Survival of revised cups, with end-point cup re-revision for any reason was 82.2% (95%CI: 78.8–85.1) at 5 years follow-up. Out of 532 stem revisions, 89 stem re-revisions were registered. For revised stems, survival at 5 year follow-up, with endpoint stem re-revision for any reason was 82.0% (95%CI: 78.2–85.2).

The outcome of revised acetabular and femoral components is worrisome, with a survival of 82% at 5 years follow-up. This information is valuable to provide realistic expectations for these young patients at time of primary THA.

In recent years, there has been increasing interest in the use of simultaneous hip arthroplasty compared to staged procedures in patients with bilateral pathology. The aim of this study was to compare simultaneous and staged hip arthroplasty in patients with bilateral pathology by assessing the transfusion rate, postoperative hemoglobin drop, length of stay (LOS), in-hospital complications, 30-days readmissions, leg length difference and early functional outcome.

We conducted a retrospective cohort study that included all patients who were undergoing primary total hip arthroplasty (THA) by a single surgeon in a high-volume arthroplasty center between 2015 and 2020 as simultaneous or staged procedures. Staged bilateral arthroplasties were performed within 12 months and were stratified by the time between procedures. Data was acquired through the electronic files at the Orthopädische Chirurgie München (OCM). For functional outcome we compared the ability of the patients to walk independently on the ward and the ability to walk a set of stairs alone which was recorded daily by the attending physiotherapist.

In total n=290 patients were assessed for eligibility and included in this study. One hundred and thirty eight patients were allocated to the staged arthroplasty group. The second staged procedure was performed within 12 months of the first procedure. One hundred and fifty two patients were allocated to the simultaneous arthroplasty group. No statistical difference was found between the two groups regarding demographic data. Primary outcome measurements: There was no significant difference in transfusion rate or complication rate (p=0.1147). In both groups the transfusion rate was actually 0%. Secondarily, no statistically significant difference was found between the postoperative hemoglobin drop (p=0.1147) and the functional outcome (p=0.7249), nor the length of stay (LOS) (p=: 0.6415), as well as the 30 days readmission rate between both groups. No difference was found in leg length in the simultaneous group. The OR time in the simultaneous group ranged from 62min to 111min with an average of 77min. No surgery exceeded a 120min window.

We observed no significant differences in transfusion rate, in hospital complications, as well as readmission rate between both groups. The early functional outcome showed no significant difference in mobility. Simultaneous hip arthroplasty is as safe as a staged procedure, with no higher risk for the patient, in a specialized high volume center with a specialized surgeon and an adequate team. Level of evidence: Level IV

Detection of clinical situations are the most difficult for primary THA and factors which determine the complexity.

Results of 2368 primary THA performed by one surgeon in 1923 patients with various hip pathologies from 2004 to 2016 were analyzed. The time of the surgery, the bloodloss, the features of the surgical technique, the implants used, and the incidence of complications and revisions were assessed and X-ray analysis was performed.

Difficult cases of primary hip arthroplasty include severe dysplasia (types B2, C1, and C2 according to the Hartofilakidis classification), post-traumatic segmental acetabular defects and pelvic discontinuity, protrusio acetabuli, iatrogenic bone ankylosis and consequences of proximal femur fractures with significant shortening of the limb.

X-ray signs of difficulty included an interruption of the Shenton line of 2 cm or more (except for acute fractures of proximal femur), the femoral neck-shaft angle less than 100°, and the horizontal distance from Kohler line to center of rotation less than 20% of the diameter of the femoral head. An additional burdening factor is the previous surgical interventions on the hip joint.

The ten-year survival rate for standard cases was 94.9%, and for complex cases − 92.3%. The odds ratio development of complications in complex cases compared to standard cases is OR = 8.402 (95% CI from 4.614 to 15.300). In standard cases mean HHS increased from 42.9 points before surgery to 95.3 after surgery. In complex cases mean HHS before surgery was 38.9 and after surgery improved to 81.6 points, p <0.001.

The complexity of the operation cannot be determined on the basis of only the etiological factor, it is necessary to take into account the severity of anatomical changes.

Highly crosslinked polyethylene (HXLPE) has been used with great clinical success in total hip arthroplasty (THA) since its debut in the late 1990's. However, reports regarding this bearing couple in its second decade of service are still scant. The aim of this study was to 1. Determine the long term clinical and radiological results and 2. Investigate what factors affect wear rates using a metal-on-HXLPE bearing articulation.

55 THA's using a single brand of HXLPE liner, cementless cup and 28mm hip ball were performed in 44 patients. Age, sex, and Charlson Comorbidity Index (CCI) and need for revision surgery were recorded. Linear and volumetric wear was determined using the Martell method.

Mean age at operation was 51.2 (29–73 +/− 12.1) years. Mean duration of follow up was 16.9 years (range 15.0–20.1 +/− 1.1 years). Osteolysis was not present in the latest follow up radiographs.

Median linear and volumetric wear rate was 0.035mm/year (95% CI 0.031–0.047) and 7.12mm³/year (95% CI 6.92–17.25) respectively. Acetabular component position was not found to be related to both linear and volumetric wear. No significant difference was found in the linear and volumetric wear rates of thinner and thicker liners (8mm or below and > 8mm) (p=0.827 and p=0.843 respectively).

HXLPE is associated with very low linear and volumetric wear rates which has virtually obviated osteolysis and has translated to excellent survivorship even at long term follow up. In-vivo oxidation does not appear to be of clinical concern at this point in its service cycle.

The purpose of this study was to compare oxinium versus metal-on-polyethylene wear in two consecutive prospective randomized series of low friction total hip arthroplasty at a minimum 10-year follow-up.

A total of 100 patients with a median age of 60.9 years were randomized to receive either oxinium (50 hips) or metal (50 hips) femoral head. The polyethylene socket was EtO sterilized in the first 50 patients, whereas it was highly cross-linked and remelted (XLPE) in the following 50 patients. The primary criterion for evaluation was linear head penetration measurement using the Martell system by an investigator blinded to the material. Also, a survivorship analysis was performed using wear related loosening revised or not as the end point.

Complete data were available for analysis in 40 hips at a median follow-up of 12.9 years (11 to 14), and in 36 hips at a median follow-up of 12.3 years (10 to 13) in the EtO sterilized and XLPE series, respectively.

In the EtO sterilized series, the mean steady-state wear rate was 0.245 ± 0.080 mm/year in the oxinium group versus 0.186 ± 0.062 mm/year in the metal group (p = 0.009). In the XLPE series, the mean steady-state wear rate was 0.037±0.016 mm/year in the oxinium group versus 0.036±0.015 mm/year in the metal group (p = 0.94). The survival rate at 10 years was 100% in both XLPE series, whereas it was 82.9% (IC 95%, 65–100) and 70.5% (IC95%, 50.1–90.9) in the metal-EtO and oxinium-EtO series, respectively.

This RCT demonstrated that up to 14-year follow-up, wear was significantly reduced when using XLPE, irrespective of the femoral head material. Also, no osteolysis related complication was observed in the XLPE series. In the current study, oxinium femoral heads showed no advantage over metal heads and therefore their continued used should be questioned related to their cost.

The aim of this study is the comparative assessment of long term clinical (subjective and objective), functional and quality of life outcome data between primary and revision THA.

122 patients (130 hips) who underwent cementless revision THA of both components (TMT cup, Wagner SL stem, Zimmer Biomet) for aseptic loosening only (Group A) were compared to a matched group of 100 patients (100 hips) who underwent cementless primary THA for osteoarthritis (Synergy stem, R3 cup, Smith & Nephew) (Group B). Outcomes were evaluated with survival analysis curves, Harris hip score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Oxford hip score (OHS), Short form-12 health survey (SF-12) and EQ-5D-5L scales. Mobility was assessed with walking speed, timed up and go test (TUG), Parker mobility, Lower extremity function score (LEFS) and UCLA scores.

At a mean follow up of 14.4 years (10 to 20) a cumulative success rate of 96% (95% CI 96 to 99%) in Group A and 98% (95% CI 97 to 99%) in Group B with operation for any reason as an end point was recorded. Statistically significant differences between groups were developed for WOMAC (Mann-Whitney U test, p= 0.014), OHS (Mann-Whitney U test, p= 0.020) and physical component of SF-12 scores (Mann-Whitney U test, p= 0.029) only. In Group A, in multiple regression analysis, patients’ cognition (p=0.001), BMI (p=0.007) and pain (p=0.022) were found to be independent factors influencing functional recovery (WOMAC). Similarly, pain (p=0.03) was found to influence quality of life (EQ-5D-5).

In the long term, revision THA shows satisfactory but inferior clinical, functional, and quality of life outcomes when compared to primary THA. Residual pain, BMI and cognitive impairment independently affect functional outcomes.

The management of prosthetic joint infection (PJI) has been widely performed for total hip arthroplasties (THA), but none has compared it with hip resurfacing arthroplasty (RSA). We also carried out a retrospective case-control study comparing the surgical treatment of PJI by surgical debridement and implant retention between RSA and THA in order to clarify whether there was a difference in terms of (1) successful healing of PJI (2) functional scores after recovery (3) risk factors for recurrence of PJI. Our hypothesis was that simple debridement with prosthesis retention regardless of the timeframe allowed to obtain a higher success rate for RSA compared to THA.

From 2010 to 2018, a single-center case-control study based on 3056 RSA found 13 PJI were age-matched (based on the 139 THA PJI treated) with 15 THA PJI (mean age of 53 years old (47–58) for THA and 59 (45–66) for RSA (p=0.34)). We compared their survival (absence of infectious recurrence) and the means differences between the 2 groups (demographical, clinical and biological data).

There was no difference between the 2 groups concerning: age (p=0.3), BMI (p=0.4), initial diagnosis (p=0.4), operating time for primary surgery (p=0.3), the presence of a postoperative hematoma (p=0.4), the type of bacteria (p=0.5), the total duration of antibiotic therapy (p=0.9) and the type of antibiotic therapy (p=0.6). Early postoperative infections (less than 6 weeks) occurred in 7/13 RSA cases (54%) compared to 11/15 THA cases (73%). At the mean follow-up of 5 years (2–7), the success rate without recurrence was significantly higher in the RSA group 100% versus 66.7% (10/15) for the THA group (p=0.044). At the last follow-up, the Oxford Hip Score was higher in the RSA versus THA group's (14 versus 22 p=0.004).

Simple surgical debridement an RSA without changing implants after PJI can be done regardless of the time to onset of infection. This is secondary to the absence of metaphyseal bone invasion and the low content of joint fluid.

Two-stage exchange revision total hip arthroplasty performed in case of infection has been considered during many years the gold standard for treatment of chronic infection. Nevertheless, during the last decade, concerns have risen regarding its safety and its efficiency. The purpose of our study was to, first investigate the spacer complications, then to analyze their risks factors.

We retrospectively included 125 patients with chronic hip periprosthetic joint infection who underwent a two stage exchange revision arthroplasty performed between January 2013 and December 2019. All spacer complications were systematically collected and risk factors were analyzed. Statistical evaluation were performed using the Student and Mann-Whitney tests.

Our study confirms the hypothesis of a high-risk strategy with 42% of patients who had a mechanical spacer failure and a 20% recurrence of infection during the average two years period of follow-up. We found a high rate of spacer migration (23%) and a low rate of spacer fracture (8%) compared to literature.

The most important finding was that the majority of spacer complications and failures were found in a population with high medical comorbidities as highlighted by the ASA, Charlson and Lee score associations, as well as with the cardiac, pulmonary, kidney or hepatic chronic conditions.

This study showed that a two-stage hip exchange revision is a high-risk procedure regarding complications and mechanical failures of PMMA spacers.

In patients with high medical comorbidities, other strategies may be considered and interdisciplinary cooperation with other facilities are needed to identify and control each risk factor.

In health care, several studies have suggested worse outcomes in African-Americans. Our objective was to study the relationships of race with outcomes in a series of total hip arthroplasty (THA) cases.

A consecutive series of 2,435 total hip/knee arthroplasties (primaries and revisions) performed in a single hospital by a single surgeon were studied. Revisions due to infections were excluded. Data on race was available for 718 THAs which were finally included. Cases of African-Americans (AA) (n=55) and Whites (n=663) were compared on baseline demographics, Charlson, ASA, preoperative-diagnosis; preoperative and postoperative pain intensity/frequency visual-analogue-scale, QWB-7, SF-36, WOMAC, Hip Harris, Postel-D'Aubigne scores; and on postoperative transfusion rates. T-tests, Chi-Square, MANCOVA (age, ethnicity, BMI, and preoperative-diagnosis adjustments) were used. Mean follow-up: 3 years. Alpha was set at 0.05.

At baseline and compared to Whites, African-Americans were significantly younger (mean, 67 vs. 59 years), had fewer Hispanics (61% vs. 26%), and had higher BMI (28.5 vs. 30.6 Kg/m²) (all p≤0.048), respectively. Preoperative diagnoses were significantly different (p<0.001). There were no significant differences between the groups on preoperative scores after adjusting for confounders. Postoperatively, SF-36 bodily-pain (70 vs. 57), SF-36 mental-component-summary (56 vs. 53), WOMAC-total (5 vs. 12), and WOMAC-stiffness (0.14 vs. 0.57) were significantly worse in African-Americans (all p≤0.043), respectively. African-Americans underwent more transfusions (28% vs. 65%, p=0.001).

Compared to Whites, African-Americans underwent THA earlier in life, with higher BMI, and different preoperative-diagnosis. They also had worse postoperative scores and more transfusions. Race seems to be strongly associated with outcomes.

Although periacetabular osteotomies are widely used for the treatment of symptomatic acetabular dysplasia, the surgical outcomes after long term follow-up are still limited. Thus, we assessed hip survival and patient-reported outcomes (PROMs) at 20 years after the transposition osteotomy of acetabulum (TOA).

Among 260 hips in 238 patients treated with TOA, 172 hips in 160 patients were evaluated at average 20.8 years, excluding patients who died or lost to follow-up. Kaplan-Meier analysis was used to assess survivorship with an end-point of THA. PROMs were evaluated using the VAS satisfaction, VAS pain, Oxford hip score (OHS), and Forgotten joint score (FJS). The thresholds of favorable outcomes of FJS and OHS were obtained using the receiver-operating characteristic curve with VAS satisfaction ≥ 50 and VAS pain < 20 as anchors.

Thirty-three hips (19.2%) underwent THA at average 13.3 years after TOA. Kaplan-Meier analysis revealed hip survival rate at 20 years was 79.7%. Multivariate analysis showed the preoperative Tönnis grade significantly influenced hip survival. Survival rates with Tönnis grade 0, grade 1, and grade 2 were 93.3%, 86.7%, and 54.8% at 20 years, respectively. More than 60% of the patients showed favorable PROMs (VAS satisfaction ≥ 50, VAS pain < 20, OHS ≥ 42, FJS ≥ 51). Advanced Tönnis grade at the latest follow-up and higher BMI were significantly associated with unfavorable OHS, but not with other PROMs.

This study demonstrated the durability of TOA for hips with Tönnis grade 0–1 and favorable satisfaction in majority of the patients at 20 years after surgery. Current presence of advanced osteoarthritis is associated with the lower hip function (OHS), but not necessarily associated with subjective pain and satisfaction. Higher BMI also showed a negative impact on postoperative function.

Hemiarthroplasty (HA) and total hip arthroplasty (THA) have both been well described as effective methods of management for displaced femoral neck fractures in the elderly. THA has superior functional outcomes and lower long-term revision rates, while HA is associated with lower dislocation rates and faster operative times. While HA remains an appropriate management option in low-demand patients, it is commonly complicated by acetabular erosion. However, there is no consensus about the preferred method of treatment in self-sufficient, physically active patients with normal cognition. The aim of this study was to evaluate the impact of age in geriatric patients with acetabular wear after bipolar HA.

We retrospectively reviewed the records of all cases of femoral neck fractures treated with bipolar HA in our institution, during the period 2013 – 2020. According to the age at the time of fracture, patients were separated in 3 groups: Group A (age 70 – 75), group B (age 75 – 80) and group C (age > 80). Acetabular wear was defined as failure of the acetabulum, which needed revision to THA.

A total of 1410 patients (861 females and 549 males, mean age 77,2 years) were included in the study. 359 patients were included in Group A, 592 in Group B and 459 in Group C. Mean follow-up was 3.2 years. There were no significant differences in sex distribution, injury side, fracture pattern, BMI, ASA score, bipolar head diameter and leg length discrepancy among the 3 groups. The incidence of acetabular wear and need for revision to THA was 6.13%, 4.22% and 1.96% respectively (p = 0.009).

The higher rate of acetabular wear in patients less than 75 years suggests that THA is a more viable option for these patients. In group 75–80 years old decision for HA or THA should be made upon patient's activity status and biological age while above the age of 80 years old, Hemi seems to be the preferred solution.