Revision total hip arthroplasty using the Kerboull acetabular reinforcement device for Paprosky type III defects involving the inferior margin of the acetabulum: a minimum five-year follow-up study.

Aims: The purpose of this retrospective study was to evaluate the minimum five-year outcome of revision total hip arthroplasty (THA) using the Kerboull acetabular reinforcement device (KARD) in patients with Paprosky type III acetabular defects and destruction of the inferior margin of the acetabulum. Patients and Methods: We identified 36 patients (37 hips) who underwent revision THA under these circumstances using the KARD, fresh frozen allograft femoral heads, and reconstruction of the inferior margin of the acetabulum. The Merle d'Aubigné system was used for clinical assessment. Serial anteroposterior pelvic radiographs were used to assess migration of the acetabular component. Results: At a mean follow-up of 8.2 years (5 to 19.3), the mean Merle d'Aubigné score increased from 12.5 (5 to 18) preoperatively to 16.5 (10 to 18) (p < 0.0001). The survival rate at ten years was 95.3% (sd 4.5; 95% confidence interval (CI) 86.4 to 100) and 76.5% (sd 9.9, 95% CI 57.0 to 95.9) using aseptic loosening and radiological loosening as the endpoints, respectively. Conclusion: These results show that the use of the KARD with reconstruction of the inferior margin of the acetabulum in revision THA is associated with acceptable clinical results and survival at mid-term follow-up with, however, a high rate of migration of the acetabular component of 21.6%. Cite this article: Bone Joint J 2018;100-B:725-32.

Current recommendations for assessing the reliability of a measurement tool: a survival guide for orthopaedic surgeons.

UNLABELLED: Previous standards for assessing the reliability of a measurement tool have lacked consistency. We reviewed the most current American Society for Testing and Materials and International Organisation for Standardisation (ISO) recommendations, and propose an algorithm for orthopaedic surgeons. When assessing a measurement tool, conditions of the experimental set-up and clear formulae used to compile the results should be strictly reported. According to these recent guidelines, accuracy is a confusing word with an overly broad meaning and should therefore be abandoned. Depending on the experimental conditions, one should be referring to bias (when the study protocol involves accepted reference values), and repeatability (sr, r) or reproducibility (SR, R). In the absence of accepted reference values, only repeatability (sr, r) or reproducibility (SR, R) should be provided. TAKE HOME MESSAGE: Assessing the reliability of a measurement tool involves reporting bias, repeatability and/or reproducibility depending on the defined conditions, instead of precision or accuracy.

A randomised controlled trial comparing highly cross-linked and contemporary annealed polyethylene after a minimal eight-year follow-up in total hip arthroplasty using cemented acetabular components.

Most published randomised controlled trials which compare the rates of wear of conventional and cross-linked (XL) polyethylene (PE) in total hip arthroplasty (THA) have described their use with a cementless acetabular component. We conducted a prospective randomised study to assess the rates of penetration of two distinct types of PE in otherwise identical cemented all-PE acetabular components. A total of 100 consecutive patients for THA were randomised to receive an acetabular component which had been either highly XL then remelted or moderately XL then annealed. After a minimum of eight years follow-up, 38 hips in the XL group and 30 hips in the annealed group had complete data (mean follow-up of 9.1 years (7.6 to 10.7) and 8.7 years (7.2 to 10.2), respectively). In the XL group, the steady state rate of penetration from one year onwards was -0.0002 mm/year (sd 0.108): in the annealed group it was 0.1382 mm/year (sd 0.129) (Mann-Whitney U test, p < 0.001). No complication specific to either material was recorded. These results show that the yearly linear rate of femoral head penetration can be significantly reduced by using a highly XLPE cemented acetabular component.

A comparison of patient-specific and conventional instrumentation for total knee arthroplasty: a multicentre randomised controlled trial.

In this study we randomised 140 patients who were due to undergo primary total knee arthroplasty (TKA) to have the procedure performed using either patient-specific cutting guides (PSCG) or conventional instrumentation (CI). The primary outcome measure was the mechanical axis, as measured at three months on a standing long-leg radiograph by the hip-knee-ankle (HKA) angle. This was undertaken by an independent observer who was blinded to the instrumentation. Secondary outcome measures were component positioning, operating time, Knee Society and Oxford knee scores, blood loss and length of hospital stay. A total of 126 patients (67 in the CI group and 59 in the PSCG group) had complete clinical and radiological data. There were 88 females and 52 males with a mean age of 69.3 years (47 to 84) and a mean BMI of 28.6 kg/m(2) (20.2 to 40.8). The mean HKA angle was 178.9° (172.5 to 183.4) in the CI group and 178.2° (172.4 to 183.4) in the PSCG group (p = 0.34). Outliers were identified in 22 of 67 knees (32.8%) in the CI group and 19 of 59 knees (32.2%) in the PSCG group (p = 0.99). There was no significant difference in the clinical results (p = 0.95 and 0.59, respectively). Operating time, blood loss and length of hospital stay were not significantly reduced (p = 0.09, 0.58 and 0.50, respectively) when using PSCG. The use of PSCG in primary TKA did not reduce the proportion of outliers as measured by post-operative coronal alignment.

A cemented acetabular component with a reinforcement cross provides excellent medium-term fixation in total hip arthroplasty after pelvic irradiation.

Conventional cemented acetabular components are reported to have a high rate of failure when implanted into previously irradiated bone. We recommend the use of a cemented reconstruction with the addition of an acetabular reinforcement cross to improve fixation. We reviewed a cohort of 45 patients (49 hips) who had undergone irradiation of the pelvis and a cemented total hip arthroplasty (THA) with an acetabular reinforcement cross. All hips had received a minimum dose of 30 Gray (Gy) to treat a primary nearby tumour or metastasis. The median dose of radiation was 50 Gy (Q1 to Q3: 45 to 60; mean: 49.57, 32 to 72). The mean follow-up after THA was 51 months (17 to 137). The cumulative probability of revision of the acetabular component for a mechanical reason was 0% (0 to 0%) at 24 months, 2.9% (0.2 to 13.3%) at 60 months and 2.9% (0.2% to 13.3%) at 120 months, respectively. One hip was revised for mechanical failure and three for infection. Cemented acetabular components with a reinforcement cross provide good medium-term fixation after pelvic irradiation. These patients are at a higher risk of developing infection of their THA.

Revision of primary total hip arthroplasty for peri-prosthetic fracture: A prospective epidemiological study of 249 consecutive cases in France.

BACKGROUND: Revision total hip arthroplasty (reTHA) for peri-prosthetic fracture (PPF) is increasingly performed but still ranks fourth among reasons for reTHA in registries. In France, no specific registry is available and the frequency of PPF among reasons for THA revision is therefore unknown. Here, our objectives were to determine the relative frequency of PPF as a reason for reTHA, to identify patient-related and primary-THA-related factors associated with reTHA for PPF, to describe reTHA modalities for PPF, and to determine the morbidity and mortality associated with reTHA for PPF. HYPOTHESIS: PPF is the second most common reason for reTHA, after loosening. METHODS: Consecutive reTHA procedures performed in 30 French centres over a 2-year period were collected prospectively. Repeat revisions and revisions of hemi-arthroplasties were excluded. The epidemiological, clinical, and surgical data needed to answer the questions of the study were collected. RESULTS: PPF was the second leading reason for reTHA (249/2107, 11.8%). Vancouver type B2 fractures were the most common (n=127 [51.5%]). Compared to patients who underwent reTHA for reasons other than PPF, those with reTHA for PPF were older at primary THA (67.9 years versus 57.7 years) and more often had intra-operative complications (16.9% versus 11.6%); furthermore, the primary THA was more often cementless (62.7% versus 42.7%) with a dual-mobility cup (20.6% versus 11.1%). At reTHA, the patients with PPF were older (77.6 years versus 69.2 years), had worst medical condition (mean ASA score, 2.4 versus 2.1) and less physically active (mean Devane score, 2.1 versus 2.4). The patients with reTHA for PPF had a shorter time to revision (9.8 years versus 11.4 years), a longer operative time (144 minutes versus 128 minutes), and more frequent use of the posterior approach (77% versus 67%) with a cementless dual-mobility cup (78% versus 60%) and a cementless revision femoral stem (72% versus 50%). Morbidity and mortality rates were high (5.9% operative complication rate and 12% of surgical complications with 4.8% mortality within the first 3 months) however, these results were similar to those in the rest of the cohort. DISCUSSION AND CONCLUSION: PPF is the second most common reason for reTHA, a result that is at variance with data in national registries. LEVEL OF EVIDENCE: Level IV, prospective observational cohort study.

Oxinium femoral head damage generated by a metallic foreign body within the polyethylene cup following recurrent dislocation episodes.

Oxinium femoral heads are supposed to be more scratch-resistant thanks to their oxidized layer. However, damages to this thin layer can jeopardize implant's properties. Following revision total hip arthroplasty performed for recurrent posterior dislocations, the Oxinium femoral head initially implanted was observed to be dramatically damaged. A metallic foreign body from a trochanteric fixation wire was found within the polyethylene cup. Only few cases of damaged Oxinium femoral heads have been reported and all were related to either dislocation or reduction of THA. The aim of this report is to describe a non-reported mechanism of damaged Oxinium femoral head due to a broken trochanteric fixation wire device. Any broken metallic wire from a transtrochanteric approach should be carefully followed to detect migration within the polyethylene cup. If such a migration occurs, revision surgery should be rapidly scheduled.

Primary total hip arthroplasty revision due to dislocation: prospective French multicenter study.

INTRODUCTION: Dislocation following total hip arthroplasty (THA) may require surgical revision, and is one of the most frequent causes for revision in national registers. The goals of this study were to determine the characteristics of revision THA for dislocation and identify the typical features of hips revised due to dislocation. MATERIALS AND METHODS: A prospective multicenter study (30 centers) was performed in first revision THA performed between January 1, 2010 and December 31, 2011 (multiple revisions were excluded). RESULTS: Two hundred nineteen (10.4%) of all first revisions (2153 cases in 2107 patients) were for dislocation, which was the fifth cause of revision. There were 135 men and 84 women, mean age 65.9 years old (24.3-92.4) at primary THA and 72.9 years old (31.9-98.8) at revision. Revision surgery was performed a mean 7.1 years (± 7.1) after primary THA. The predictive risk factors for dislocation were: a 22.2mm diameter femoral head (risk × 2.4), a posterolateral approach (risk × 1.7), older age (risk × 1.1), an elevated rim liner for primary THA (risk × 6.6). The use of a dual mobility cup did not influence the rate of revision for dislocation (8.8%) compared to the use of a flat rim liner (9.1%). DISCUSSION: The 10.4% rate of revision of THA for dislocation seems markedly lower than the results in the literature both for frequency and ranking. The use of elevated rim or constrained liners designed to decrease the risk of dislocation does not improve results compared to standard liners. LEVEL OF EVIDENCE: Level IV, prospective prognostic study without a control group.

Infection as a cause of primary total hip arthroplasty revision and its predictive factors.

INTRODUCTION: Infection is a serious complication of total hip arthroplasty (THA) and is one of the most frequent causes of failure. The goal of this study was to evaluate the importance of infection among the different causes of revision THA and identify any risk factors specifically associated with this cause of revision. MATERIALS AND METHODS: All patients who underwent a first revision of THA were included in a prospective multicenter study. Postoperative clinical and radiological evaluation and follow-up of morbidity and mortality were performed at 3 months. RESULTS: Two hundred forty out of 2107 revisions (11.4%) were performed for infected THA, which was the third cause after aseptic loosening (42.3%) and peri-prosthetic fractures (11.8%). These patients had a higher BMI associated with co-morbidities and lower clinical scores than patients with other causes of revision. One-stage revision was performed in most cases (66%) with replacement of the complete implant in 86% of cases, resulting in longer surgery compared to that for other causes. Male gender (OR 2.3), avascular necrosis (OR 2.4), arthroplasties with dual mobility cups (OR 2.5) and a Rottinger anterolateral approach (OR 3.4) were all associated with an increased risk of infection. DISCUSSION: Some of these risk factors are not or have rarely been reported in the literature. They should be taken into consideration to help in the prevention and continuing battle against THA infection. LEVEL OF EVIDENCE: Level IV, prospective cohort study.

An unreported cause of early postoperative dislocation following total hip revision: massive intra-capsular oedema related to inferior vena cava filter thrombosis.

Inferior vena cava (IVC) filters are widely used to prevent pulmonary embolism (PE) in patients with an absolute or relative contraindication for anticoagulants, during the peri-operative period of trauma or total joint replacement. No complication specific to the orthopaedic's aspect of this practice has been described. We report the case of a patient who had major femoral head/cup separation mimicking dislocation following revision total hip arthroplasty related to massive intra-capsular oedema produced by IVC filter thrombosis. The patient could be successfully treated non-operatively. Orthopaedic surgeons should identify and refer patients with a complicated IVC filter, to identify any migration or occlusion, and also be aware that removable filters must not be kept in situ, once the high-risk phase of developing PE is past.

Is the so-called 'French paradox' a reality?: long-term survival and migration of the Charnley-Kerboull stem cemented line-to-line.

We have evaluated the in vivo migration patterns of 164 primary consecutive Charnley-Kerboull total hip replacements which were undertaken in 155 patients. The femoral preparation included removal of diaphyseal cancellous bone to obtain primary rotational stability of the stem before line-to-line cementing. We used the Ein Bild Roentgen Analyse femoral component method to assess the subsidence of the femoral component. At a mean of 17.3 years (15.1 to 18.3) 73 patients were still alive and had not been revised, eight had been revised, 66 had died and eight had been lost to follow-up. The mean subsidence of the entire series was 0.63 mm (0.0 to 1.94). When using a 1.5 mm threshold, only four stems were considered to have subsided. Our study showed that, in most cases, a highly polished double-tapered stem cemented line-to-line does not subside at least up to 18 years after implantation.

Impaction grafting in association with the Charnley-Kerboull cemented femoral component: operative technique and two- to 16-year follow-up results.

We describe 129 consecutive revision total hip replacements using a Charnley-Kerboull femoral component of standard length with impaction allografting. The mean follow-up was 8.2 years (2 to 16). Additionally, extramedullary reinforcement was performed using struts of cortical allograft in 49 hips and cerclage wires in 30. There was one intra-operative fracture of the femur but none later. Two femoral components subsided by 5 mm and 8 mm respectively, and were considered to be radiological failures. No further revision of a femoral component was required. The rate of survival of the femoral component at nine years, using radiological failure as the endpoint, was 98%. Our study showed that impaction grafting in association with a Charnley-Kerboull femoral component has a low rate of subsidence. Reconstruction of deficiencies of distal bone with struts of cortical allograft appeared to be an efficient way of preventing postoperative femoral fracture for up to 16 years.

[Should monobloc cemented stems be systematically revised during revision total hip arthroplasty? A prospective evaluation]. / Faut-il systématiquement changer une pièce fémorale monobloc cimentée lors d'une reprise d'arthroplastie totale ? Evaluation prospective.

PURPOSE OF THE STUDY: The main reason for revision of Charnley type total hip arthroplasty is socket loosening related to high polyethylene wear and periacetabular osteolysis. In these situations, the monobloc cemented stem is frequently not loosened and it is not clear whether the femoral component can be retained during the revision procedure. The aim of this study was to evaluate surface and sphericity damage to the femoral head of a prospective and consecutive series of revision total hip arthroplasties during which the cemented monobloc femoral component has been systematically revised. MATERIALS AND METHODS: We performed 22 revisions of both components of Charnley type cemented total hip arthroplasties. In all cases, the 22.2 mm head of the monobloc femoral component was made of 316 L stainless steel. The international standard for such femoral heads includes an average surface roughness (Ra) of 0.05 microm, a total roughness (Rt) value of 0.5 microm and a sphericity of +/-5 microm. The mean age of the patients at the time of the index arthroplasty was 51.3 years. The average time to revision was 14.8 years (seven to 25 years). The reasons for revision included isolated socket loosening (12), extensive periacetabular osteolysis without socket loosening (two), recurrent dislocation associated with socket loosening (one), sepsis without implant loosening (one), loosening of both components (one), and isolated loosening of the femoral component (five). Hence, 15 of the 22 (68.2%) femoral components could theoretically have been retained. The surface roughness of the femoral heads was evaluated using a contact-type profilometer. For each head, the apex and two zones, either macroscopically scratched or with loss of the mirror finish, were analyzed. Moreover, the sphericity of the heads was measured using a spherometer. RESULTS: The stem explanted after recurrent dislocation was analyzed separately as the femoral head had major scratches. The mean Ra and Rt of the series at the apex was 0.029 and 0.876 microm, respectively. The mean Ra and Rt of the series for the macroscopically damaged areas was 0.05 microm and 1.540 microm, respectively. The mean sphericity of the series was 7.2 microm. Hence among the 22 explanted stems, 10 femoral heads (45.4%) had Ra or Rt apex and 18 (81.8%) Ra or Rt scratched area values beyond ISO standards, respectively. Sphericity was greater than +/-5mm for 13 of the 22 femoral heads (59.1%). With the numbers available, the age at the time of the index arthroplasty, the BMI, the time and the reason for revision were not significantly associated with the degree of femoral head damage for both roughness and sphericity parameters. DISCUSSION: Retaining the femoral component during revision of the total hip arthroplasty including a monobloc femoral component is theoretically an interesting alternative. However, femoral head surface damage occurring in vivo would have lead us to retain severely scratched heads in over 80% of the hips, and heads with abnormal roughness and sphericity values in over 90% of the hips. Bases upon our results, we recommend systematically revising the femoral component during revision THA including a monobloc stem, irrespective of the reason for revision.

A comparison of the penetration rate of two polyethylene acetabular liners of different levels of cross-linking. A prospective randomised trial.

We carried out a prospective randomised study designed to compare the penetration rate of acetabular polyethylene inserts of identical design but different levels of cross-linking at a minimum of four years follow-up. A total of 102 patients (102 hips) were randomised to receive either highly cross-linked Durasul, or contemporary Sulene polyethylene inserts at total hip replacement. A single blinded observer used the Martell system to assess penetration of the femoral head. At a mean follow-up of 4.9 years (4.2 to 6.1) the mean femoral head penetration rate was 0.025 mm/year (SD 0.128) in the Durasul group compared with 0.106 mm/year (SD 0.109) in the Sulene group (Mann-Whitney test, p = 0.0027). The mean volumetric penetration rate was 29.24 mm(3)/year (SD 44.08) in the Durasul group compared with 53.32 mm(3)/year (SD 48.68) in the Sulene group. The yearly volumetric penetration rate was 55% lower in the Durasul group (Mann-Whitney test, p = 0.0058). Longer term results are needed to investigate whether less osteolysis will occur.

[Clinical evaluation tools of total hip arthroplasties]. / Outils d'évaluation clinique des arthroplasties totales de hanche.

Total hip arthroplasty is one of the most efficient hip surgery procedures enabling improved function in the vast majority of operated patients. The major long-term complication is aseptic loosening due to an inflammatory response to particle wear debris coming from the bearings. Polyethylene is the key culprit. Currently two solutions are proposed: eliminating polyethylene from the prosthetic articulation or reducing material wear. This leads to the need for reliable tools for evaluating short-term results, predictive of long-term outcome. When the innovation concerns reduction of polyethylene wear, short-term wear should be measured with software methods or radiostereometry. If the innovation concerns improvement of polyethyleneless implants, then short-term migration should be measured with EBRA or radiostereometry. In addition, the long-term retrospective evaluation of large series of patients remains of major interest provided that it is performed with survival analysis. These different methods are detailed in this study, indicating the pros and cons for each solution.

[Early femoral osteolysis following Charnley-Kerboull total hip arthroplasty combining a 22-mm zirconia head on polyethylene]. / Ostéolyse fémorale précoce après arthroplastie totale de hanche Charnley-Kerboull a tête zircone 22 sur polyéthylène.

PURPOSE OF THE STUDY: New bearings have been developed to reduce polyethylene wear. Zirconia ceramic is one proposal with attractive tribologic properties. The purpose of this prospective study was to evaluate the clinical and radiological results at least two years after implantation in a continuous series of total hip arthroplasties combining a zirconia head with polyethylene socket. MATERIAL AND METHODS: The series included 56total hip arthroplasties performed in 51 patients (30 females and 21 males), mean age 52.2 +/- 12 years (25-76 years). Prostheses were implanted for primary degenerative disease (43%) and dysplasia (27%). The femoral component was a stainless steel stem with a Morse cone measuring 11degrees 25' for 27 hips and 5 degrees 40' for 28 hips. A 22-mm stabilized yttrium tetragonal polycrystalline zirconia head (Y-TZP) was used. The transtrochanteric approach was used for all arthroplaties with implantation of a cemented Charnley-Kerboull prosthesis. Clinical outcome was assessed with the Postel-Merle-d'Aubligné (PMA) score. Acetabular cup wear and periprosthetic osteolysis were measured on successive AP x-rays of the pelvis. RESULTS: Mean follow-up was 32 months (24-48). None of the patients were lost to follow-up. Mean function score at last follow-up was 17.8 +/- 0.2 (16-18) versus 12.2 +/- 2.6 preoperatively (Wilcoxon, p < 0.0001). There were no cases of implant migration (femoral or acetabular). An endosteal defect by femoral osteolysis in the calcar femoral was observed in 19 of 55 cases. It appeared early between first and second post-operative year and did not progress later. Its surface remained less than 1 cm2 in all cases. We were unable to identify any factor predictive of these osteolytic lesions. DISCUSSION: The short-term clinical results with this type of arthroplasty was comparable with earlier results described with classical Charnely-Kerboull implants using a metal-polyethylene bearing. The Merkel osteolysis observed in this series occurred early for one-third of the hips with no measurable polyethylene wear. We suggest surgeons should be cautious about using the zirconia head. We are continuing our surveillance of these patients.

DNA microarray allows molecular profiling of rheumatoid arthritis and identification of pathophysiological targets.

This study was undertaken to evaluate the possibility to obtain a molecular signature of rheumatoid arthritis (RA) comparatively osteoarthritis (OA), and to lay the bases to develop new diagnostic tools and identify new targets. Microarray technology was used for such an analysis. The gene expression profiles of synovial tissues from patients with confirmed RA, and patients with OA were established and compared. A set of 63 genes was selected, based, more specifically, on their overexpression or underexpression in RA samples compared to OA. Results for six of these genes have been verified by quantitative PCR using both samples identical to those used in the microarray experiments and entirely separate samples. Expression profile of the 48 known genes allowed the correct classification of additional RA and OA patients. Furthermore, the distinct expression of three of the selected genes was also studied by quantitative RT-PCR in cultured synovial cells. Detailed analysis of the expression profile of the selected genes provided evidence for dysregulated biological pathways, pointed out to chromosomal location and revealed novel genes potentially involved in RA. It is proposed that such an approach allows valuable diagnosis/prognostics tools in RA to be established and potential targets for combating the disease to be identified.

Total hip arthroplasty for Crowe type IV developmental hip dysplasia: a long-term follow-up study.

A consecutive series of 118 total hip arthroplasties was performed for Crowe type IV developmental hip dysplasia in 89 patients. The mean age of the patients was 52 years. All procedures were carried out through a transtrochanteric approach by the same surgeon. In all cases, the acetabular component was placed at the level of the true acetabulum. The mean lengthening of the operated limb was 3.8 cm. The average follow-up of the whole series was 12.8 years. At the last follow-up evaluation, 29 patients (35 hips) had died or were lost to follow-up at a mean of 11 years. Sixty patients (83 hips) were still alive at a mean follow-up of 16 years. At the time of last follow-up, the mean Merle d'Aubigné hip score was 17.4 compared with 10.6 preoperatively. The survival rate, with revision for any reason as the endpoint, was 78% at 20-year follow-up.