How modular porous metal augments have changed the management of acetabular bone loss at primary or revision total hip arthroplasty.

The advent of modular porous metal augments has ushered in a new form of treatment for acetabular bone loss. The function of an augment can be seen as reducing the size of a defect or reconstituting the anterosuperior/posteroinferior columns and/or allowing supplementary fixation. Depending on the function of the augment, the surgeon can decide on the sequence of introduction of the hemispherical shell, before or after the augment. Augments should always, however, be used with cement to form a unit with the acetabular component. Given their versatility, augments also allow the use of a hemispherical shell in a position that restores the centre of rotation and biomechanics of the hip. Progressive shedding or the appearance of metal debris is a particular finding with augments and, with other radiological signs of failure, should be recognized on serial radiographs. Mid- to long-term outcomes in studies reporting the use of augments with hemispherical shells in revision total hip arthroplasty have shown rates of survival of > 90%. However, a higher risk of failure has been reported when augments have been used for patients with chronic pelvic discontinuity.

Cup positioning and its effect on polyethylene wear of vitamin E- and non-vitamin E-supplemented liners in total hip arthroplasty: radiographic outcome at 5-year follow-up.

BACKGROUND: Aseptic loosening remains a challenging problem after total hip arthroplasty. Accurate cup placement and supplementation of antioxidants in acetabular liners might reduce material failure rates. The aim of this study is to assess the effect of the cup position on the wear behaviour of UHMWPE-XE and UHMWPE-X liners in vivo using virtual radiographs. METHODS: We conducted a prospective, randomized, controlled, multicenter trial. Clinical data of 372 probands were analyzed. Anteroposterior pelvic X-rays of 324 patients immediately postoperatively and after 1 and 5 years were evaluated by the RayMatch® analysis software regarding cup position and wear behaviour. RESULTS: Mean cup anteversion was 20.3° (± 7.4) and inclination was 41.9° (± 7.0) postoperatively. 62.3% of all patients had an anteversion and inclination within the Lewinnek safe zone. Anterior and anterolateral approaches led to significantly higher cup anteversion compared to lateral approaches (27.3° ± 5.5; 20.9° ± 7.2; 17.5° ± 6.6; p < 0.001 and p = 0.001, respectively). Mean anteversion increased to 24.6° (± 8.0) after 1 year (p < 0.001). Only one revision occurred because of implant dislocation. Wear rates from UHMWPE-X and UHMWPE-XE did not differ significantly. Anteversion angles ≥ 25° correlated to increased polyethylene wear (23.7 µm/year ± 12.8 vs. 31.1 µm/year ± 22.8, p = 0.012) and this was amplified when inclination angles were ≥ 50° (23.6 µm/year ± 12.8 vs. 38.0 µm/year ± 22.7, p = 0.062). CONCLUSION: Anterior approaches lead to the highest inaccuracy of cup placement, but cup positioning outside the Lewinnek safe zone does not necessarily cause higher dislocation rates. Moreover, mean anteversion increased by approximately four degrees within the first year after operation, which is expected to be functional due to a regularization of pelvic tilt after intervention. Mid-term wear rates of UHMWPE-X and UHMWPE-XE liners are comparable, but steep cup positions lead to significantly increased polyethylene wear. In summary, a re-evaluation of target zones for intraoperative cup positioning might be considered. In the long-term reduced oxidative embrittlement could lead to superior wear behaviour of vitamin E-blended liners.

Fix and replace: Simultaneous fracture fixation and hip replacement for acetabular fractures in older patients.

INTRODUCTION: Displaced acetabular fractures in the elderly present significant treatment challenges. The 'fix and replace' concept involves open reduction and internal fixation of the acetabulum, providing bony stability to accept the press-fit of an acetabular cup, with a cemented femoral stem. This allows early mobilisation and the advantages this confers. This study of 57 patients treated with fix and replace describes our technique, outcomes, and survival analysis. METHODS: A retrospective review of 57 'fix and replace' procedures in patients aged over 60 was performed. Data was collected on mechanism, fracture type, demographics, time to surgery, comorbidity index, complications, EQ-5D and Oxford hip scores (OHS). Radiographs were reviewed for fracture healing, implant loosening, cup migration, and heterotopic ossification. RESULTS: 57 patients aged 60 to 95 had fix and replace surgery. The median ASA score was 3. The mean Charlson Index was 4.8. 45 patients had a low-energy fall, 6 had a road traffic accident, 3 fell off a bicycle, and 1 mechanism was unclear. The fracture patterns were anterior column posterior hemitransverse (67%), associated both columns (9%), posterior column (9%), posterior column and posterior wall (9%), and transverse (2%). The mean time to surgery was 8.4 days (0-14). 26 out of 57 (46%) received a blood transfusion. Mean length of stay was 17.6 days (7-86). The mean follow-up was 35.5 months. 4 dislocations were treated with closed reduction, whilst 1 required excision arthroplasty. 2 infections resolved with debridement, antibiotics, and implant retention (DAIR), whilst 1 required a two-stage revision. 1 acetabular component had migrated requiring revision. The median pre-injury OHS was 44 (26-48) compared to 37.3 (28-48) at 1 year. There were no deaths at 30-days, whilst at 1 year 7 patients had died. Kaplan Meier survival analysis showed mean survival was 1984.5 days. Implant survival was 90% at 1 year. CONCLUSION: While fix and replace is conceptually attractive, this medically complex patient group requires considerable support peri­ and post-operatively. Further studies are required to provide clinicians with more information to decide on how best to provide a holistic management strategy for such injuries in this frail patient cohort.

A novel hip joint prosthesis with uni-directional articulations for reduced wear.

A novel polymer-on-metal hip joint prosthesis design that makes use of uni-directional articulations was developed and tested in this work. The new implant was tested using two polymer variants, virgin ultra-high molecular weight polyethylene (UHMWPE), and Vitamin E-infused highly crosslinked polyethylene (VEHXPE). The degrees of freedom of the ball-and-socket are reproduced by three cylindrical orthogonally-aligned articulations. This unconventional design leverages on the molecular orientation hardening mechanisms of the polyethylene and increased contact area to minimize wear. An experimental hip joint simulator was used to compare the gravimetric wear of the conventional ball-on-socket and the new implant. The new prosthesis including UHMWPE components produced a 78% reduction in wear, whereas the new prosthesis with VEHXPE components produced a 100% reduction in wear, as no measurable wear was detected. Machining marks on the acetabular cups of the new prosthesis were retained for both polyethylene variants, further demonstrating the low levels of wear exhibited by the new implants. Both polyethylene materials produced particles in the range of 0.1-1.0 µm, which are the most biologically active. Nonetheless, the extremely low wear rates are likely to induce minimal osteolysis effects. Furthermore, the novel design also offers an increase of more than 24% in the range of motion in flexion/extension when compared to a dual-mobility hip implant. A prototype of the prosthesis was implanted into a Thiel-embalmed human cadaver during a mock-surgery, which demonstrated high resistance to dislocation and the possibility of performing a figure of four position.

Fracturas por epilepsia en el hospital Víctor Lazarte Echegaray / Epilepsy Fractures at Víctor Lazarte Echegaray Hospital

Introducción: Las convulsiones pueden producir una tensión muscular significativa capaz de fracturar el hueso. Se halló que el aumento significativo en la incidencia de fracturas se encuentra dentro del grupo de edad entre 45 a 64 años, lo que demuestra que los epilépticos no solo son más vulnerables a las fracturas, sino que tienen un comienzo de fractura más precoz. Las medidas de prevención comprenden suplementos de calcio, vitamina D, densitometría ósea y tratamiento con bifosfonatos, que deben reforzarse en pacientes con epilepsia que tienen riesgo de osteoporosis. Objetivo: Presentar casos de fracturas extracapsular e intracapsular de la cadera por convulsiones epilépticas, atendidos en el hospital Víctor Lazarte Echegaray, Trujillo, Perú, en el periodo comprendido entre 2013 y 2019. Presentación de los casos: Se reporta dos casos de fractura de cadera por convulsiones epilépticas, uno con fractura del acetábulo e iliaco izquierdo y otro a nivel del cuello femoral y subtrocantérica. Conclusiones: Las personas con convulsiones epilépticas poseen un mayor peligro de fracturas, por consiguiente se recomienda a los médicos que maximicen su conciencia sobre las fracturas relacionadas a convulsiones, en especial a pacientes con dolor postictal, debido a que los síntomas pueden ser inespecíficos y una mala interpretación puede impedir la rehabilitación(AU)

Introduction: Seizures can produce significant muscle tension capable of fracturing the bone. The significant increase in the incidence of fractures was found to be within the age group between 45 and 64 years, which shows that epileptics are not only more vulnerable to fractures, but also have earlier fracture onset. Prevention measures include calcium supplements, vitamin D, bone densitometry, and bisphosphonate treatment that should be reinforced in patients with epilepsy who are at risk for osteoporosis. Objective: To present cases of hip fractures due to epileptic seizures, treated at Víctor Lazarte Echegaray Hospital, Trujillo, Peru, from 2013 to 2019. Case report: Cases of hip fracture due to epileptic seizures have been reported, one with fracture of the acetabulum and left iliac and another at the level of the femoral and subtrochanteric neck. Conclusions: Individuals with epileptic seizures have greater risk of fractures, it is recommended that physicians maximize their awareness of seizure-related fractures, especially in patients with postictal pain, since the symptoms can be nonspecific and misinterpretation can prevent rehabilitation(AU)

Vitamin E-blended highly cross-linked polyethylene liners in total hip arthroplasty: a randomized, multicenter trial using virtual CAD-based wear analysis at 5-year follow-up.

BACKGROUND: Progressive oxidation of highly cross-linked ultra-high molecular weight (UHMPWE-X) liners is considered to be a risk factor for material failure in THA. Antioxidants such as vitamin E (alpha-tocopherol) (UHMWPE-XE) were supplemented into the latest generation of polyethylene liners. To prevent inhomogenous vitamin E distribution within the polymer, blending was established as an alternative manufacturing process to diffusion. The purpose of the present study was to investigate the in vivo wear behavior of UHMWPE-XE in comparison with conventional UHMWPE-X liners using virtual CAD-based radiographs. METHODS: Until now, 94 patients from a prospective, randomized, controlled, multicenter study were reviewed at 5-year follow-up. Of these, 51 (54%) received UHMWPE-XE and 43 (46%) UHMWPE-X liners. Anteroposterior pelvic radiographs were made immediately after surgery and at 1 and 5 years postoperatively. The radiographs were analyzed using the observer-independent analysis software RayMatch® (Raylytic GmbH, Leipzig, Germany). RESULTS: The mean wear rate was measured to be 23.6 µm/year (SD 13.7; range 0.7-71.8 µm). There were no significant differences between the two cohorts (UHMWPE-X: 23.2 µm/year vs. UHMWPE-XE: 24.0 µm/year, p = 0.73). Cup anteversion significantly changed within the 1st year after implantation independent from the type of polyethylene liner [UHMWPE-X: 18.2-23.9° (p = 0.0001); UHMWPE-XE: 21.0-25.5° (p = 0.002)]. No further significant changes of cup anteversion in both groups were found between year 1 and 5 after implantation [UHMWPE-X (p = 0.46); UHMWPE-XE (p = 0.56)]. CONCLUSION: The present study demonstrates that the addition of vitamin E does not adversely affect the midterm wear behavior of UHMWPE-X. The antioxidative benefit of vitamin E is expected to become evident in long-term follow-up. Cup anteversion increment by 5° within the 1st year is likely a result of the released hip flexion contracture resulting in an enhanced posterior pelvic tilt. Therefore, a reassessment of target values in acetabular cup placement might be considered.

Acetabular avascular necrosis following high-dose steroid treatment and chemotherapy for leukemia : Computer tomography analysis of treatment with impaction bone grafting.

Avascular necrosis (AVN) of the bone is thought to be a serious complication of treatment for acute lymphoblastic leukemia (ALL). The acetabulum is an unusual area to be affected by AVN, and there are currently no reports of successful joint salvage procedures found in the literature. We present a case of a 20-year-old man with ALL who was diagnosed with debilitating AVN of both acetabula 2 years following initial diagnosis of ALL and treatment with a multi-agent chemotherapy regimen including high-dose corticosteroids. After unsuccessful treatment with bisphosphonate therapy, the acetabular AVN underwent bilateral curettage and impaction bone grafting to prevent collapse of subchondral fractures with the hope of salvaging both hip joints. Computer tomography (CT) of the AVN affected areas, pre- and post-bone impaction grafting, demonstrated healing of the subchondral fractures and a doubling of bone density that was maintained at 2 years after surgery. The patient resumed full weight-bearing at 3 months after first surgery, continues to ambulate unrestricted, and remains pain free 3 years post-surgery.

Adapter Sleeves Are Not Needed to Reduce the Risk of Fracture of a New Ceramic Head Implanted on a Well-Fixed Stem.

The purpose of this study was to assess (1) the prevalence of the fracture of ceramic heads implanted on used trunnions of well-fixed stems without using a titanium adapter sleeve; (2) the prevalence of trunnionosis secondary to fretting and/or corrosion at the trunnion of the well-fixed stem; and (3) clinical and radiographic results and the survival rate of the revised acetabular components. Eighty-eight patients (100 hips) underwent isolated revision of the acetabular components for polyethylene wear and osteolysis of the acetabulum. The study group consisted of 70 men and 18 women with a mean age of 52.8 years (range, 31-54 years) when the primary total hip arthroplasty was performed. Evidence of fretting and corrosion of the trunnion of all prostheses was examined macroscopically using a magnifying lens. Degree of fretting and corrosion of the trunnion was assessed using a 4-point scoring technique. A new 36-mm alumina delta ceramic head was implanted on the trunnion of a well-fixed stem without using a titanium adapter sleeve in all hips. The mean follow-up after revision of the acetabular component was 12.8 years (range, 10-14 years). Among the 100 new ceramic heads implanted on a well-fixed stem, no fracture of the ceramic head occurred at a mean follow-up of 12.8 years. The median fretting and corrosion scores for the trunnions were 1.5±1.1 and 1.3±0.9 points, respectively. The mean Harris hip score at the final follow-up was 89±15 points (range, 63-100 points). Survivorship of the revised acetabular components at 14 years was 95% (95% confidence interval, 87.6%-98.6%). [Orthopedics. 2018; 41(3):158-163.].

Modified Stoppa approach for operative treatment of acetabular fractures: 10-year experience and mid-term follow-up.

INTRODUCTION: The (modified) Stoppa approach for acetabular fracture surgery has gained significant popularity and early results have been encouraging but clinical outcome at extensive follow-up is scarce. The purpose of this study is to provide an update on our experience with this approach for operative treatment of acetabular fractures and to assess clinical outcome at mid-term follow-up. METHODS: In this retrospective study, all patients treated operatively for an acetabular fracture using the Stoppa approach over a 10-year period were included. Surgery details were reviewed and patients were contacted and requested to return for follow-up. Primary outcome was native hip survivorship, secondary outcome measures included; functional outcome (Merle d'Aubiginé, Harris hip) scores, health-related quality of life (short-form 36) and radiographic outcome (heterotopic ossification, hip osteoarthritis). RESULTS: Forty-five patients received operative fixation for 47 acetabular fractures using the Stoppa approach. Complications requiring surgical intervention were found in one patient (with a vascular lesion) intra-operatively and 3 patients (with wound infections (2) and diffuse bleeding (1)) post-operatively. Follow-up was 83% and 29/39 (74%) native hips survived at mean 59 months (SD 49) postoperatively. Excellent-good functional scores were found in 88% (Merle d'Aubiginé) and 76% (Harris hip) of patients who had retained their native hip. Most (6/8) short-form 36 indices in these patients were comparable to population norms. Of 29 native hips with radiographic follow-up (mean 59 months (SD 49), 4 (86%) had no-minimal radiographic abnormalities. CONCLUSION: This study confirms that the Stoppa approach is a safe and effective technique for acetabular fracture fixation. Moreover, at mid-term follow-up, this approach is associated with satisfactory results in terms of hip survivorship as well as functional and radiographic outcome. As such, our findings reinforce the notion that this less invasive technique presents a valuable alternative to the ilioinguinal approach for the surgical treatment of acetabular fractures.

Clinical Outcomes and Bearing-Specific Complications Following Fourth-Generation Alumina Ceramic-on-Ceramic Total Hip Arthroplasty: A Single-Surgeon Series of 749 Hips at a Minimum of 5-Year Follow-Up.

BACKGROUND: The purpose of this study is to evaluate the minimum 5-year outcomes and bearing-specific complications in a single surgeon series of fourth-generation alumina ceramic-on-ceramic total hip arthroplasties (THAs). METHODS: We retrospectively analyzed 667 patients (749 hips) who underwent primary THAs by a single surgeon using fourth-generation alumina ceramic bearings. There were 315 men and 352 women with a mean age of 54.2 years. The surgeon used cementless prostheses with an identical design and BIOLOX Delta ceramics in all hips, using a 36-mm head in 472 hips (63%) and a 32-mm head in 227. The mean follow-up duration was 6.5 years (range, 5 to 8 years). RESULTS: The mean Harris hip score improved from 45.6 points preoperatively to 91.3 points at final follow-up. All but 1 acetabular cup and all femoral stems were well fixed. No radiographic evidence of osteolysis was identified at final follow-up. There were 2 (0.3%) ceramic liner fractures and no ceramic head fractures. A total of 48 hips (6.4%) exhibited audible noise (29 clickings and 19 squeakings), but no patient required revision. Other complications were 1 dislocation, 1 deep infection, 3 iliopsoas tendonitis, and 6 periprosthetic femoral fractures. Kaplan-Meier survivorship for revision for any reason was 98.6% (95% confidence interval, 97.7-99.5) at 6.5 years. CONCLUSION: Delta ceramic-on-ceramic THAs had a high rate of survivorship without radiographic evidence of osteolysis at 6.5-year follow-up. However, we found 0.3% ceramic liner fractures and 6.4% audible noises associated with the use of Delta ceramics.

The Ideal Total Hip Replacement Bearing Surface in the Young Patient: A Prospective Randomized Trial Comparing Alumina Ceramic-On-Ceramic With Ceramic-On-Conventional Polyethylene: 15-Year Follow-Up.

BACKGROUND: The optimum bearing surface for total hip arthroplasty remains debatable. We have previously published our outcome at 10 years and this represents the 15-year follow-up. METHODS: A total of 58 hips (in 57 patients with a mean age of 42 years) were randomized to receive either ceramic-on-ceramic (CoC) or ceramic-on-polyethylene (CoP) total hip arthroplasty. We prospectively followed for survivorship, functional outcomes (using the Harris Hip Score and the St Michael's Hip Score [SMH]), and radiological outcomes. RESULTS: At a minimum of 15 years, 3 patients had died, but not been revised. Seven were lost to follow-up. Five cases from the CoP group were revised (4 for polyethylene wear and osteolysis). Four from the CoC were revised; one each for head fracture, instability, infection, and trunnionosis. Both groups showed statistically significant improvements in Harris Hip Score scores and SMH functional scores, with no difference between the 2 bearings. For the CoP group, there was an improvement from 15.6 to 21.5 in the SMH and from 48.8 to 88.7 (P > .05); and for CoC, this improvement was 15.8 to 23.5 and 50.3 to 94.6 (P > .05), respectively. Mean wear rate of the polyethylene was 0.092 mm/y and for the CoC was 0.018 mm/y. Two patients in the CoC group had evidence of acetabular osteolysis vs 3 in the CoP. Six patients had femoral osteolysis in the CoC group and 12 in the CoP group. CONCLUSION: Survivorship and function of the 2 bearing groups remains comparable; while the polyethylene wear and osteolysis may represent issues in the future.

A Minimum Ten Years of Follow-Up of Alumina Head on Delta Liner Total Hip Arthroplasty.

BACKGROUND: In the early days when delta ceramics were developed, there was a period of using delta ceramic liner and alumina ceramic head. Therefore, the purpose of this study is to investigate the clinical and radiological outcomes of total hip arthroplasty using delta ceramic liner on alumina ceramic head after a minimum of 10 years of follow-up and to evaluate problems of early delta ceramic liner. METHODS: Alumina on delta cementless total hip arthroplasty was performed in 92 hips (85 patients) from August 2005 to March 2007 at our hospital. Bilateral total hip arthroplasty were performed in 7 patients, 30 patients on the left side and 48 patients on the right side. Preoperative diagnosis was osteonecrosis of the femoral head in 34 hips (37%), degenerative arthritis in 31 hips (33.7%), femur neck fracture in 21 hips (22.8%), and rheumatoid arthritis in 6 hips (6.5%). All surgeries were carried out with anterolateral approach. For the clinical evaluation, Harris hip score (HHS), pain, and range of motion were assessed. Radiographs were reviewed by the authors to search for any signs of osteolysis, loosening of implants, and heterotopic ossification. RESULTS: HHS was compared between preoperative and final follow-ups. The mean HHS improved from preoperative 58.3 points (range 27-76) to 92.7 points (range 78-98) on the final follow-up (P = .02). The mean range of hip motion at the final follow-up was flexion 116.9°, adduction 23.8°, abduction 34.6°, internal rotation 16.3°, and external rotation 39.2°. As for the postoperative pain, 1 patient complained of inguinal pain and 4 patients complained of thigh pain. Because of trauma, 3 cases of dislocation were observed in all cases. There are 3 cases with dislocation and 2 cases were treated with conservative treatment without recurrence, but 1 case was required for surgical treatment due to eccentric rim wear of delta liner. The aseptic loosening of acetabular cup and femoral stem was each 1 hip. CONCLUSION: Alumina head-on-delta liner cementless THA, using a large femoral head 32-36 mm in diameter, demonstrated satisfactory clinical and radiological results in the minimum 10 years of follow-up. Eccentric rim wear can occur even in delta ceramic liners that are known to have high strength, and this can lead to dislocation which can, in turn, increase the possibility of linear fracture.

A 28-year clinical and radiological follow-up of alumina ceramic-on-crosslinked polyethylene total hip arthroplasty: a follow-up report and analysis of the oxidation of a shelf-aged acetabular component.

AIMS: Our aim in this study was to describe a continuing review of 11 total hip arthroplasties using 22.225 mm Alumina ceramic femoral heads on a Charnley flanged femoral component, articulating against a silane crosslinked polyethylene. PATIENTS AND METHODS: Nine patients (11 THAs) were reviewed at a mean of 27.5 years (26 to 28) post-operatively. Outcome was assessed using the d'Aubigne and Postel, and Charnley scores and penetration was recorded on radiographs. In addition, the oxidation of a 29-year-old shelf-aged acetabular component was analysed. RESULTS: The mean clinical outcome scores remained excellent at final follow-up. The mean total penetration remained 0.41 mm (0.40 to 0.41). There was no radiographic evidence of acetabular or femoral loosening or osteolysis. There was negligible oxidation in the shelf-aged sample despite gamma irradiation and storage in air. CONCLUSION: These results highlight the long-term stability and durability of this type of crosslinked, antioxidant containing polyethylene when used in combination with a small diameter alumina ceramic femoral head. Cite this article: Bone Joint J 2017;99-B:1286-9.

Reduced survival for uncemented compared to cemented total hip arthroplasty after operatively treated acetabular fractures.

BACKGROUND: Post traumatic arthritis and avascular necrosis of the femoral head are common complications after operatively treated acetabular fractures. This may cause severe disabilities for the patient, necessitating a total hip arthroplasty. Even though an arthroplasty may provide good symptomatic relief, the long-term results are more uncertain and no consensus exists according to preferred prosthetic designs. With this cohort study, we aimed to investigate the medium to long term arthroplasty survival and clinical results of total hip arthroplasty after operatively treated acetabular fractures. METHODS: We included 52 patients treated with a secondary total hip arthroplasty at a median of 2.4 (0.1-14.1) years after an operatively treated acetabular fracture. The median age was 54 (11-82) years. Cemented arthroplasty was used for 33 patients, 10 patients had an uncemented arthroplasty and 9 patients received a hybrid arthroplasty. Average follow up was 8.0 (SD 5.0) years. RESULTS: Ten-year revision free arthroplasty survival was 79%. Uncemented arthroplasties had a significantly worse 10-year survival of 57%. Arthroplasties performed at a centre without a pelvic fracture service also had a significantly worse 10-years survival of 51%. Cox regression showed similar results with an 8-fold increase in risk of revision for both uncemented arthroplasties and operations performed at a non-pelvic trauma centre. CONCLUSION: Total hip arthroplasty secondary to an operatively treated acetabular fracture provides good symptomatic relief. These patients are, however, complex cases and are probably best treated at specialist centres with both pelvic trauma surgeons and arthroplasty surgeons proficient in complex revisions present.

Isolated revision of the acetabular component using alumina-on-alumina bearings without a metal sleeve: A preliminary study.

INTRODUCTION: There has been a debate on the use of ceramic-on-ceramic coupling with the retained femoral stem in isolated acetabular revision. The purpose of this study was to retrospectively review the results and complications of isolated revision of the acetabular component using alumina-on-alumina bearings. METHODS: Between August 2010 and December 2013, 22 patients (23 hips) with a mean age of 60.74 years (40-73) underwent isolated revision of the acetabular component from metal-on-polyethylene to alumina-on-alumina bearings without using a metal sleeve on the undamaged trunnion. All patients completed clinical and radiographic evaluation. RESULTS: At a mean follow-up of 3 years (2-5.5), all patients had a significant improvement in the clinical outcome, including Harris Hip Score (84.9 vs. 43, p < 0.001), West Ontario McMaster University Osteoarthritis Index Score (14.4 vs. 49.2, p < 0.001), and visual analogue pain score (1.42 vs. 6.63, p < 0.001). Complications included one aseptic loosening of the acetabular component and three noisy hips (click only). No fracture of the ceramic bearings, dislocation, infection, or squeaking noise were observed in any of the patients. CONCLUSION: Isolated revision of the acetabular component to alumina-on-alumina bearings on the undamaged trunnion may be considered if there is no available titanium sleeves. Our study showed a satisfactory early outcome with minimal complications. However, a longer term follow-up study is necessary.

The evolution of an uncemented acetabular component in alumina-on-alumina total hip arthroplasty has improved clinical outcome: a prospective, comparative five- to 15-year follow-up study.

AIMS: To determine the effect of a change in design of a cementless ceramic acetabular component in fixation and clinical outcome after total hip arthroplasty PATIENTS AND METHODS: We compared 342 hips (302 patients) operated between 1999 and 2005 with a relatively smooth hydroxyapatite coated acetabular component (group 1), and 337 hips (310 patients) operated between 2006 and 2011 using a similar acetabular component with a macrotexture on the entire outer surface of the component (group 2). The mean age of the patients was 53.5 (14 to 70) in group 1 and 53.0 (15 to 70) in group 2. The mean follow-up was 12.7 years (10 to 17) for group 1 and 7.2 years (4 to 10) for group 2. RESULTS: No hips were revised due to complications related to bearing fracture or to stem loosening. A total of 15 acetabular components were revised for aseptic loosening in group 1 and two in group 2. The survival rate for acetabular component aseptic loosening at eight years was 96.8% (95% confidence interval (CI) 94.8 to 98.7) for group 1 and 99.2% (95% CI 98.0 to 100) for group 2. The risk for aseptic loosening of the acetabular component was higher in group 1 (p = 0.04, Hazard Ratio (HR) 4.99), dysplastic acetabula (p = 0.01, HR 4.12), components outside Lewinnek´s zone (p < 0.001, HR 6.13) and in those with a hip rotation centre distance greater than 5 mm (p = 0.005, HR 4.09). CONCLUSION: Alumina ceramic-on-ceramic THA is an excellent option for young patients. Although newer components appeared to improve fixation, acetabular reconstruction is essential to obtain a satisfactory outcome. Cite this article: Bone Joint J 2017;99-B:749-58.

Internal fixation of acetabular fractures in an older population using the TIMI approach - Midterm results of a prospective study.

INTRODUCTION: The incidence of geriatric acetabular fractures continues to increase due to demographic changes. In the elderly, anterior column fractures are common, and standard approaches are associated with a considerable risk for surgery-associated complications. Therefore, a minimally invasive approach was developed in our department. The aim of this study was to examine early and mid-term results regarding the use of this novel two-incision minimally invasive (TIMI) approach in patients aged over 55 years with acetabular fractures. METHODS: From July 2007 to April 2014, 47 patients aged over 55 years were treated via the TIMI approach; these patients were included in the present prospective study. The patients' characteristics, data, and early phase of care were assessed during acute care. A radiological evaluation comprised pre- and postoperative CT scans and x-rays, including Judet views at follow-up. Follow-up examinations were performed after 6 and 24 months and comprised a clinical and radiological examination and an evaluation of hip function (Harris Hip Score) and health-related quality of life (EQ-5D). RESULTS: The mean age of the patients was 74±11years, with a gender ratio of 35/12 (m/f). The average operation time was 93±30min, and perioperative blood loss amounted to 858±463ml. In total, five (11%) complications associated with the operative procedure occurred, and revision surgery was necessary in three patients. We observed no wound infections, abdominal wall hernias or cases of heterotopic ossification in our sample. The Harris Hip Score at six months after surgery was 81, and it slightly improved to 84 after 24 months. The mean EQ5D index was 0.91 at six months after surgery and 0.92 at 24 months after surgery. CONCLUSION: The TIMI approach represents a valuable alternative to the ilioinguinal and modified Stoppa approach for the treatment of acetabular fractures located in the anterior column, which are often observed in geriatric patients. LEVEL OF EVIDENCE: Therapeutic Level II (Prospective cohort study).

Alumina Delta-on-Highly Crosslinked-Remelted Polyethylene Bearing in Cementless Total Hip Arthroplasty in Patients Younger than 50 Years.

BACKGROUND: The purpose of this retrospective study was to determine the clinical and radiographic results, prevalence of polyethylene wear and osteolysis, and fracture of alumina delta ceramic femoral head or highly crosslinked, remelted polyethylene (HXLPE) liner associated with the use of alumina delta ceramic femoral head-on-HXLPE bearing in cementless total hip arthroplasty in patients younger than 50 years. METHODS: We reviewed the cases of 119 patients (130 hips) who underwent a cementless total hip arthroplasty using alumina delta ceramic-on-HXLPE bearing when they were 50 years or younger at the time of surgery. The most common diagnoses were osteonecrosis (51%) and osteoarthritis secondary to developmental dysplastic hip (39%). Osteolysis and polyethylene wear rates were evaluated with use of radiography and computed tomography. In addition, prevalence of fracture of alumina delta ceramic head and polyethylene line was documented. The mean follow-up was 8.3 years (range, 7-9 years). RESULTS: The mean Harris hip score, Western Ontario and McMaster Universities Osteoarthritis Index score, University of California, Los Angeles activity score were 94 points, 14 points, and 8.1 points, respectively, at the final follow-up. No patient had thigh pain. All acetabular components and all but one femoral components were well fixed. The mean annual penetration rate of femoral head was 0.022 ± 0.003 mm/year. No hip had osteolysis or ceramic head or HXLPE liner fracture. CONCLUSION: Our average 8.3-year results with the use of alumina delta ceramic-on-HXLPE bearing in the patients younger than 50 years suggest that cementless acetabular and femoral components provide a high survival rate without evidence of osteolysis or ceramic head or AXLPE liner fracture.

Alumina Delta-on-Alumina Delta Bearing in Cementless Total Hip Arthroplasty in Patients Aged <50 Years.

BACKGROUND: There are limited studies to evaluate long-term clinical and radiographic outcomes of alumina delta ceramic-on-ceramic bearings in cementless total hip arthroplasty (THA). The purpose of this study was to evaluate the clinical and radiographic results, prevalence of osteolysis, squeaking, and fracture of ceramic material associated with the use of the alumina delta ceramic-on-alumina delta ceramic bearing in cementless THA in patients aged <50 years. METHODS: We reviewed the cases of 277 patients (334 hips) who underwent a cementless THA using alumina delta ceramic-on-alumina delta ceramic when they were 50 years or younger at the time of surgery. Demographic data; Harris Hip Score; Western Ontario McMaster Universities Osteoarthritis Index; and University of California, Los Angeles activity score were recorded. Radiographic and computerized tomographic evaluations were used to evaluate implant fixation and osteolysis. Squeaking sound and ceramic fracture were documented. The mean follow-up was 13.1 years (range, 10-14). RESULTS: The mean postoperative Harris Hip Score, Western Ontario and McMaster Universities Osteoarthritis Index score, University of California, Los Angeles activity score were 93 points, 15 points, and 8.6 points, respectively. Two patients had thigh pain (grade 7 points). All acetabular components and all but 2 femoral components were well fixed. Thirty-three hips (10%) exhibited clicking sound, and 2 hips (0.6%) exhibited squeaking sound. No hip had osteolysis or ceramic head or liner fracture. CONCLUSION: Our minimum 10-year follow-up results with the use of alumina delta ceramic-on-alumina delta ceramic bearings in patients aged <50 years suggest that cementless THA provides a high rate of survivorship without evidence of osteolysis or fracture of ceramic material.

Acetabular distraction: an alternative for severe acetabular bone loss and chronic pelvic discontinuity.

Acetabular bone loss is a challenging problem facing the revision total hip replacement surgeon. Reconstruction of the acetabulum depends on the presence of anterosuperior and posteroinferior pelvic column support for component fixation and stability. The Paprosky classification is most commonly used when determining the location and degree of acetabular bone loss. Augments serve the function of either providing primary construct stability or supplementary fixation. When a pelvic discontinuity is encountered we advocate the use of an acetabular distraction technique with a jumbo cup and modular porous metal acetabular augments for the treatment of severe acetabular bone loss and associated chronic pelvic discontinuity.