Prosthetic knee arthritis due to Granulicatella adiacens after dental treatment.

We report prosthetic knee arthritis in a 55-year-old diabetic man due to Granulicatella adiacens, a micro-organism present in the oral flora, usually described in endocarditis but rarely in prosthesis joint infection. This patient had undergone a dental extraction without antibiotic prophylaxis one month before, and an aseptic loosening of the prosthesis had been diagnosed previously. If antimicrobial prophylaxis against infective endocarditis for dental procedures is well established, such an approach is still controversial for joint prosthesis and should be considered in some conditions.

Occurrence of noise in alumina-on-alumina total hip arthroplasty. A survey on 284 consecutive hips.

BACKGROUND: Alumina-on-alumina bearings have been accepted as a valuable alternative for young and active patients. Alumina fractures, and socket loosening were the main complications reported. But, with the increasing number of prostheses implanted, noise occurrence appeared as a new concern. The primary aim of the present study was to quantify the prevalence of noticing noise in a population having received alumina-on-alumina total hip arthroplasty as well as its eventual impact on outcome. PATIENTS AND METHODS: Two hundred and eighty-four ceramic-on-ceramic hips were performed in 238 patients from January 2003 to December 2004. The average age was 52.4 ± 13.4 years (range, 13 to 74 years). All the hips received the same prosthesis (Ceraver-Osteal™) with alumina bearing components (Ceraver-Osteal™): 32 mm liners were used for cups of 50mm or larger and 28 mm liners for cups smaller than 48 mm; the minimal alumina thickness was 6mm. The acetabular component (Cerafit™) was hemispherical, coated with a hydroxyapatite layer and press-fit fixed. The stem (Cerafit™) was a straight tapered cementless stem, fully coated with a hydroxyapatite layer. Clearance between femoral head and liner was between 20 and 50 microns. A retrospective survey was conducted by an independent surgeon who did not participate to surgery in 2007. He conducted phone interviews of patients using a standard questionnaire. No suggestion was offered on how they could describe the noise and they felt free to use the word that they considered to be the most adapted. Satisfaction was evaluated. When the noise was present, X-rays were taken to assess if sign of bearings fracture was present. RESULTS: Four patients (six hips) died of unrelated causes during the follow-up period. Three patients (three hips) live outside France and could not be followed (1.3%). Nine patients (10 hips) could not be traced and were considered lost to follow-up (3.8%). Two hundred and twenty-two patients with 265 hips, therefore, were included (nine using bearing components in 28 mm diameter and 265 in 32 mm). Twenty-eight hips experienced noise generation (10.6%). It was defined as a snap for six patients, as a cracking sound by six, as rustling by six patients, as a squeaking by seven patients (2.6%), a tinkling by two patients, one patient was unable to define the sound she felt. No factor related to the patient influenced the occurrence of noise. Twelve patients were dissatisfied with the result of their hip prosthesis, five of them experienced noise (41.7%); 210 were satisfied or very satisfied, 23 of them experiencing noise (11%); this difference was significant (P=0.002). CONCLUSION: The origins of noise occurrence are unknown. Squeaking may be related to generation of stripe wear and absence of sufficient lubrication. Other types of noise can be due to microseparation, occult dislocation, impingement between the femoral neck and the acetabular rim. LEVEL OF EVIDENCE: Level IV. Retrospective study.

Alumina-on-alumina hip arthroplasty in patients younger than 30 years old.

UNLABELLED: THA in patients younger than 30 years old presents challenges: the initial technical challenge relates to the initial disease that often causes deformities making reconstruction difficult, while the long-term challenge is wear and subsequent osteolysis and component loosening. Ceramic-on-ceramic prostheses may represent a valuable option to reduce wear. We retrospectively studied 101 patients (132 hips) with ceramic-on-ceramic prostheses implanted from 1977 to 2004. As a result of the long span of time, different implant designs and modes of fixation were used. The average age of the patients was 23.4+/-5 years (range, 13-30 years), and the main indication for THA was femoral head necrosis. The minimum followup was 1 year (mean, 6.9 years; range, 1-26.5 years). We documented 17 revisions (13%) for aseptic loosening. Twelve were for isolated acetabular loosening, two for isolated femoral loosening, and three for loosening of both components. Survivorship was 82.1% at 10 years and 72.4% at 15 years. Inferior survivorship was observed for THA performed after secondary arthritis related to slipped capital epiphysis or trauma. Limited osteolysis was observed in one hip. The main limiting factor in this series was the fixation of the acetabular component. However, improvements in the design and in the mode of fixation of this component should enhance long-term results. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Hybrid alumina total hip arthroplasty using a press-fit metal-backed socket in patients younger than 55 years. A six- to 11-year evaluation.

Between 1990 and 1992, we implanted 71 hybrid alumina-on-alumina hip arthroplasties in 62 consecutive patients under the age of 55 years, with a mean age of 46 years at surgery. There were 56 primary and 15 secondary procedures. The prostheses involved a cemented titanium alloy stem, a 32 mm alumina head, and a press-fit metal-backed socket with an alumina insert. Three patients (four hips) died from unrelated causes. Four hips had revision surgery for either deep infection, unexplained persistent pain, fracture of the alumina head, or aseptic loosening of the socket. The nine-year survival rate was 93.7% with revision for any cause as the end-point and 98.4% with revision for aseptic loosening as the end-point. The outcome in the surviving patients (50 patients, 57 hips) with a minimum five-year follow-up (mean eight years) was excellent in 47 hips (82.5%), very good in eight (14%), good in one and fair in one. A thin, partial, lucent line, mainly in zone III was present in 38% of the sockets and one socket had a complete lucency less than 1 mm thick. One stem had isolated femoral osteolysis. There was no detectable component migration nor acetabular osteolysis. This hybrid arthroplasty gave satisfactory medium-term results in active patients. The press-fit metal-backed socket appeared to have reliable fixation in alumina-on-alumina hip arthroplasty. The excellent results using cemented fixation of the stem may be related to the low production of wear debris.

Prevention of wear and osteolysis: alumina-on-alumina bearing.

Alumina-on-alumina bearings in total hip replacement have been used for 30 years. Excellent tribologic properties and extra low debris generation could, in theory, provide an answer to osteolysis. A review of the authors' experience with alumina-on-alumina bearings showed that, except in a few bearings that had been loose for a long time, osteolysis was not a problem. Although the cemented titanium stem and the alumina-on-alumina couple were not a problem, fixation of the socket had to be improved. To improve the socket fixation system and to avoid the use of a cemented titanium stem that may have created problems in the long-term, a new design was introduced in 1997. The current authors present the preliminary results of the first 96 hips with cementless fully-coated hydroxyapatite titanium alloy stems and sockets, 32-mm alumina femoral head, and alumina liner, both held with a Morse taper. Ninety-six consecutive hips in 89 patients (57 males, 32 females) with a median age of 46 years (range, 14-72 years) were analyzed. One socket was revised at 4 months because of poor primary stability in a patient with a severe acetabular fracture. One patient experienced a traumatic fracture of the implanted femur 3 weeks after surgery. The mean followup was 16 months (range, 4-38 months). One patient died from rupture of an aneurysm. Ninety-three hips in 86 patients were assessed regarding the clinical and radiologic ratings. Two patients (two hips) were interviewed by telephone. The Merle d'Aubigné rating system was 18 in 65 hips (59 patients), 17 in 25 hips (25 patients), and 16 in three hips (three patients) mainly related to a previous disability including limp, sciatic palsy, or stiffness. Examination of 93 available radiographs revealed no ostelolysis, no radiolucent lines at the last examination, and no subsidence. The level of excellent results, even in this young population, and lack of osteolysis and wear are encouraging, even if the followup is too short to allow any conclusions to be made.

Alumina-on-alumina total hip prostheses in patients 40 years of age or younger.

To avoid the consequences of polyethylene wear in a high-risk population, 128 alumina-on-alumina total hip arthroplasties have been done in 104 consecutive patients. The maximum age of patients was 40 years. The main preoperative diagnoses were osteonecrosis and sequellae of congenital hip dislocation (71% of the hips). The same titanium alloy cemented stem was implanted in all of the hips. Four types of alumina acetabular component fixations were used: a cemented plain alumina socket (41 hips), a screw-in ring with an alumina insert (22 hips), a press-fit plain alumina socket (32 hips), and a press-fit titanium metal back with an alumina insert (33 hips). Eight patients (11 hips) died during the followup period. Sixteen revisions have been documented, 12 for acetabular aseptic loosening, three for bipolar loosening (two of which were septic), and one for unexplained pain. Eighty-eight hips in 74 patients have been followed up radiologically for 2 to 22 years. Wear was unmeasurable. Four additional sockets showed definite migration. The respective survival rates after 7 years were 94.1% for the cemented cup, 88.8% for the screw-in ring, 95.1% for cementless press-fit plain alumina socket and 94.3% for the metal-back press-fit component. The 10-year survival rate was 90.4% for the cemented socket and 88.8% for the screw-in ring. The 15-year survival rate was 78.9% for the cemented socket. Grafting was the only prognostic factor, with a survival rate of 62.6% after 10 years for the hips with a bone graft and of 90.1% for hips without a graft. The alumina-on-alumina bearing surfaces seem to be a valuable alternative to the standard metal-on-polyethylene system for young patients. However, an improvement in socket fixation is required to lengthen the life span of the prosthesis to match the life expectancy of this demanding population.

Press-fit metal-backed alumina sockets: a minimum 5-year followup study.

Two hundred thirty-four consecutive alumina-on-alumina hip replacements using a press-fit metal-backed socket, performed on 214 patients (98 women, 116 men) have been reviewed. These included 201 primary procedures and 33 revision procedures. The median age of the patients at the time of surgery was 62 years (range, 21-83 years). Fourteen patients (16 hips) died from unrelated causes. Eleven patients (11 hips) underwent a total hip arthroplasty revision for recurrent dislocation (one hip), deep infection (two hips), fracture of alumina femoral head (one hip), persistent hip pain (one hip) and aseptic loosening (six hips). The survival rate after 9 years was 93.4% when revision of the prosthesis was considered the end point, and 97.4% if revision of the prosthesis for aseptic loosening was considered the end point. Results were assessed in the surviving patients with a minimal 5-year followup (170 patients, 184 hips). At the median followup of 7.8 years, the average Merle d'Aubigné and Postel score had improved from 11.9- to 17.7. Results were graded as excellent in 148 hips (80.5%), very good in 31 hips (17%), good in two hips (1%), and fair in three hips (1.5%). Radiologic data were documented for 134 patients (143 hips). Three sockets (2%) had a complete and nonprogressive radiolucent line less than 1-mm thick, one stem (0.7%) had lucencies involving five zones, and two stems (1.4%) had isolated femoral osteolysis. Neither component migration nor acetabular osteolysis were detected. A press-fit metal-backed socket may offer a good solution for alumina socket fixation when combined with a careful surgical technique of implantation.

[Cementless acetabular fixation with solid alumina sockets. Apropos of 62 total hybrid prostheses with press-fit alumina sockets at 6-year mean follow-up]. / Fixation acétabulaire non cimentée de cupules en alumine massive. A propos de 62 prothèses totales hybrides à frottement alumine/alumine au recul moyen de 6 ans.

PURPOSE OF THE STUDY: In order to avoid polyethylene wear observed in total hip replacement, an alumina-alumina combination has been used since 1977. The aim of this prospective study was to assess the results of an alumina-alumina total hip arthroplasty with a cementless press-fit plain alumina socket and a cemented titanium alloy stem with special attention for socket fixation because of previously encountered problems. MATERIALS AND METHODS: Fifty-five patients (62 hips) were operated on between 1982 and 1990. The main parameter for inclusion was a high level activity demand. The bearing surfaces were a 32 mm alumina head articulating within the alumina socket. Mean follow-up was 6 years. RESULTS: Four revisions occurred in this series: 3 for aseptic loosenings of the socket and 1 for femoral head fracture. Considering acetabular revision for aseptic loosening as the end point, the survival rate was 93.2 % at six years and 78.8 % at six years when considering acetabular loosening as the end point. At a mean of 72.1 month-follow-up, 92.4 % of the remaining hips were graded as very good or good while 44.6 % showed radiolucent lines around the socket and 4 had migrated with no radio-clinical correlation. On the femoral side, there was no radiolucent line nor loosening, and the value of the colar calcar resorption was low (mean 0.4 mm). In all four revisions, the stem was left in place, and there was no bone loss, which allowed simple revisions. DISCUSSION: Thin radiolucent lines around bulk alumina press-fit sockets can be understood as a normal bone reaction to material as the Young's modulus is much higher. They do not necessarily signify mechanical failure of the fixation. However when considering the rate of acetabular loosening, an improvement of the alumina/bone interface is still required.

[Osteoconductive properties of bioactive glasses in a bulk form and as a coating on alumina]. / Evaluation du caractère ostéoconducteur de verres bioactifs sous forme massive et en revêtement sur de l'alumine.

INTRODUCTION: Alumina on alumina friction couple has proven its reliability in the field of total hip arthroplasty. However, loosening of the alumina socket has been responsible for most of the failures. An improvement of the bone/alumina interface could be achieved with the use of an osteconductive material as a coating on alumina. The aim of this study was to evaluate the osteconductive properties of two types of bioactive glasses as a coating on alumina substrates. MATERIALS AND METHODS: Two types of coated implants (silicate glass coated alumina - AVSi, and phosphate glass coated alumina - AVP) were evaluated in a rabbit cancellous bone model. Pure alumina implants (A) were used as negative controls and bulk glasses (silicate - VSi and original 45S5, and phosphate glasses -VP) as negative controls. Sacrifices were performed at 3, 12 and 24 weeks. The interface evaluation included histomorphometry using an image analyzer. RESULTS: Silicate glasses demonstrated high osteoconductive properties. However, non mineralized osteoid tissue was the main tissue in contact with both coated implants and bulk phosphate glasses. This tissue covered over 70 p. 100 after 24 weeks of implantation, while it was never observed around pure alumina implants after 3 weeks. DISCUSSION: Amongst the hypotheses that could explain this mineralization inhibitory process, the one involving an Al(3+) glasses contamination from Al(2) O(3) is the likeliest. The high temperature coating procedure could be responsible for alumina transformation into a more soluble phase.

Ceramic/ceramic total hip arthroplasty.

Alumina-on-alumina total hip arthroplasty has been used for 30 years, mainly in Europe. The theoretical advantages of this combination are represented by its remarkable sliding characteristics, its very low wear debris generation, and its sufficient fracture toughness. These advantages are achieved if the material is properly controlled with high density, high purity, and small grains. The authors summarize the results obtained with ceramic/ceramic total hip arthroplasty. Information is provided about in vivo behavior regarding wear debris characterization and quantification, and histological tissue examinations for inflammatory reactions, which were not encountered except when alumina debris was mixed with metal or cement. Modification of socket fixation resulted in improved clinical outcomes. With a press-fit metal shell and an alumina liner utilized for 10 years, the results are excellent especially in a young and active population. Alumina-on-alumina seems at the moment to be one of the best choices when a total hip arthroplasty has to be performed in young and active patients.

Cementless bulk alumina socket: preliminary results at 6 years.

To avoid polyethylene wear observed in total hip replacement, an alumina-alumina combination has been used since 1977. The aim of this study is to report the results of a hybrid alumina-alumina total hip arthroplasty with a cementless press-fit bulk alumina socket and a cemented titanium alloy stem in 55 patients (62 hips) operated on between 1982 and 1990. The bearing surfaces were a 32-mm alumina head articulating within the alumina socket. Four failures occurred: 3 aseptic loosenings of the socket and 1 femoral head fracture. Considering aseptic loosening as the endpoint, the survival rate was 93.2% after 6 years. At a mean of 72.1 months' follow-up, 92.4% of the surviving hips were graded as very good or good using the Merle d'Aubigné-Postel hip score. Radiolucent lines were observed on the acetabular side in 68.1 of the hips. The future of this interface, which is probably fibrous, remains questionable. With the exception of 1 femoral head fracture, all revisions were related to failure of the bony fixation of the socket, and no problem was encountered related to the alumina-alumina friction coupling. Alumina sockets with other types of cementless fixation have therefore been designed and are presently under clinical investigation.

Ten-year survivorship of cemented ceramic-ceramic total hip prosthesis.

In the first 187 consecutive alumina-alumina combination hip arthroplasties performed from 1977 to 1979, both components were cemented with conventional techniques. At ten-year follow-up evaluation, 87 patients were reviewed or interviewed by telephone, 37 were dead, 39 were lost to follow-up evaluation, and 24 failures were reoperated on before the end of ten years. The major cause of failure was aseptic loosening of the acetabular component (15 failures). Fracture of the socket and of the femoral head occurred in five patients in this series. However, these complications were not seen with components manufactured after 1979. At the end of ten years, survivorship analysis depicted a 82.59% survival rate when reoperation was considered as failure and a 88.57% rate when reoperation for aseptic loosening was considered as failure. The femoral component had a 99.16% survival rate and the acetabular component had an 88.57% survival rate when reoperation for aseptic loosening was considered as failure. Age, appearance of a two- or three-zone demarcation at the intermediate follow-up evaluation, and outer diameter of the acetabular component were the major parameters influencing the results. Better results observed in the population younger than 50 years of age may be related to the small amount of wear debris produced by the alumina-alumina combination. This combination in hip prosthesis is secure, but should be implanted in young and active patients; the outer diameter of the acetabular component must be at least 50 mm. The major problem that remains is the socket's fixation. It could be improved by a design modification, by choosing another mode of fixation, or both.