Increased metal allergy in patients with failed metal-on-metal hip arthroplasty and peri-implant T-lymphocytic inflammation.

BACKGROUND: In 16 patients with revised metal-on-metal arthroplasty and peri-implant lymphocytic inflammation, we verified the role of metal hypersensitivity by patch testing (PT) and lymphocyte transformation test (LTT). METHODS: In the 16 patients with lymphocyte dominated periprosthetic inflammation, allergy history was obtained by a questionnaire, specific serum IgE to aeroallergens was measured to assess atopy, PT to standard and metal series was performed and metal sensitivity was further assessed by LTT using blood mononuclear cells. RESULTS: Revision surgery was performed because of pain (8/16), osteolysis (4/16), dislocation (3/16) and loosening of the stem (1/16). Histological examination showed perivascular infiltrates of T lymphocytes, high endothelial venules, fibrin exudation and accumulation of macrophages with drop-like inclusions. Five patients had a history of cutaneous metal allergy and atopy was found in 25% of the patients. In 13/16 patients (81%), systemic metal sensitivity was found based on PT and/or LTT. Patch test reactions were seen in 11/16 patients (69%; partly multiple reactions/patient): 7/16 to Cobalt (Co), 7/16 to Chromium (Cr), 4/16 to Nickel (Ni), and one each to Molybdenum (Mo) and Manganese (Mn). Ten of 16 patients (62%) showed enhanced LTT reactivity to metals: 7/16 to Ni, 7/16 to Co, 5/16 to Cr, 5/16 to Mo and 4/16 to Mn. CONCLUSIONS: The lymphocyte dominated peri-implant inflammation may well reflect an allergic hyper-reactivity in these patients, given the high rate of concomitantly found metal allergy. Despite the overall incidence of metal implant allergy being low, allergic reactions should be included as differential diagnosis in failed metal-on-metal arthroplasty.

[Pathological findings in tissue surrounding revised metal/metal articulations]. / Pathologische Veränderungen im umgebenden Gewebe von revidierten Metall-Metall-Gleitpaarungen.

INTRODUCTION: The aim of the current study was to elucidate the incidence of allergic reactions to metal/metal articulations in revised total hip arthroplasties. MATERIALS AND METHODS: Between 1 January 1997 and 31 January 2002 a consecutive series of tissue samples from 13 revised total hip arthroplasties with metal/metal articulations were histopathologically examined for signs of delayed type hypersensitivity (DTH). Mean age at the time of revision of the eight women and five men was 58.7 years. The prostheses were revised after a mean follow-up of 45 months. Indications for revision were progressive osteolysis of the proximal femur in 12 cases and instability in one case. All patients were clinically and radiologically evaluated after a mean follow-up of 52 months (min. 22, max. 74) after revision. RESULTS: No signs of infection were found in either histopathological or microbiological examinations. In ten cases, perivascular lymphocytic infiltrates could be found as a sign of DTH. After revision and changing of the articulation all osteolyses healed. CONCLUSION: In 10/13 cases (76.9%) signs of DTH could be detected. The fact that all osteolyses healed after changing the articulation may give a strong hint that there is an immunological contribution to this radiological changes. Metal/metal articulations cannot be recommended as the optimum implant for young patients, as the number of patients with allergic reactions to nickel, chrome or cobalt is increasing continuously.

An unusual lymphocytic perivascular infiltration in tissues around contemporary metal-on-metal joint replacements.

BACKGROUND: Metal-on-metal bearing surfaces have been reintroduced for use during total hip replacement. To assess tissue reactions to various types of articulations, we studied the histological appearance of periprosthetic tissues retrieved from around metal-on-metal and metal-on-polyethylene total hip replacements and compared these findings with the appearance of control tissues retrieved at the time of primary arthroplasty. METHODS: Periprosthetic tissues were obtained at the time of revision of twenty-five cobalt chromium-on-cobalt chromium, nine cobalt chromium-on-polyethylene, and ten titanium-on-polyethylene total hip arthroplasties. Control tissues were obtained from nine osteoarthritic hips at the time of primary total hip arthroplasty. Each tissue sample was processed for routine histological analysis, and sections were stained with hematoxylin and eosin. Quantitative stereological analysis was performed with use of light microscopy. RESULTS: Tissue samples obtained from hips with metal-on-metal implants displayed a pattern of well-demarcated tissue layers. A prominent feature, seen in seventeen of twenty-five tissue samples, was a pattern of perivascular infiltration of lymphocytes. In ten of the tissue samples obtained from hips with metal-on-metal prostheses, there was also an accumulation of plasma cells in association with macrophages that contained metallic wear-debris particles. The surfaces of tissues obtained from hips with metal-on-metal prostheses were more ulcerated than those obtained from hips with other types of implants, particularly in the region immediately superficial to areas of perivascular lymphocytic infiltration. The lymphocytic infiltration was more pronounced in samples obtained at the time of revision because of aseptic failure than in samples retrieved at the time of autopsy or during arthrotomy for reasons other than aseptic failure. Total-joint-replacement and surface-replacement designs of metal-on-metal prostheses were associated with similar results. Tissue samples obtained from hips with metal-on-polyethylene implants showed far less surface ulceration, much less distinction between tissue layers, no pattern of lymphocytic infiltration, and no plasma cells. The inflammation was predominantly histiocytic. Tissues retrieved from hips undergoing primary joint replacement showed dense scar tissue and minimal inflammation. CONCLUSIONS AND CLINICAL RELEVANCE: The pattern and type of inflammation seen in periprosthetic tissues obtained from hips with metal-on-metal and metal-on-polyethylene implants are very different. At the present time, we do not know the prevalence or clinical implications of these histologic findings, but we suggest that they may represent a novel mode of failure for some metal-on-metal joint replacements.

Intracellular measurement of polyethylene particles. A histomorphometric study.

A histological and histomorphometric study was carried out on pseudo-capsules retrieved from patients during revision surgery of cementless total hip replacement. Polyethylene loading and areal polyethylene particle size in different cells of the reticuloendothelial cell line were determined within the tissue by histomorphometry. In the reticuloendothelial cell line, foreign-body giant cells are considered to be the result of confluence of mononuclear macrophages caused by large particles or other unknown stimuli. The aim of this study was to investigate whether polyethylene particle size and polyethylene loading are different in mononuclear macrophages and foreign-body giant cells. The specimens were examined under the light-optical microscope with plain and polarized light. The polyethylene loading of 329 macrophages (mononuclear), 81 small foreign-body giant cells (2-5 visible nuclei), and 103 large foreign-body giant cells (6 or more visible nuclei) was determined and the intracellular polyethylene particle size analyzed by histomorphometry. The mean polyethylene loading was 13 +/- 8 microm2, 25 +/- 16 microm2, and 49 +/- 42 microm2, respectively. This difference was statistically significant (Student's t-test, P < 0.05). The mean polyethylene particle size was 2.34 +/- 3.2 microm2, 3.02 +/- 3.46 microm2, and 4.70 +/- 11.25 microm2, respectively. This difference was statistically significant between macrophages and large foreign-body giant cells (t-test, P < 0.05). The findings of this light-optical study show that the mean intracellular polyethylene particle size is greater in foreign-body giant cells. In addition, absolute polyethylene loading tends to be higher in foreign-body giant cells than in mononuclear macrophages.

[Experiences with the German Endoprosthesis Register]. / Erfahrungen mit dem Endoprothesenregister.

The German Endoprostheses Register started its documentation of primary and revision surgery on major joints in 1997. About 7000 primary arthroplasties and 1100 revisions on hip joints as well as 3000 primary arthroplasties and 250 revisions on knee joints are registered annually by 41 hospitals, which amounts to 60% in primary or 80% in revision surgery of the Swedish arthroplasty register. 95% of the revisions are performed on implants which have not been primarily operated on by the hospitals enrolled to the register, normally recruiting the classical "lost-to-follow-up-cases". Especially the removed implants show a conspicuous diversity of models. More than 10 specimens were removed in only 24 of 173 different types of hip-stems and 21 of 133 different types of hip-sockets. Thus, in order to cover not only a small number of types of implants by statistical analysis, large numbers of surgery have to be registered to yield case-numbers which can not be achieved by registers of small countries like the Scandinavian. Germany with approximately 1900 relevant clinical departments owns a slumbering potential that could easily be recruited.

Migration of polyethylene wear debris in one type of uncemented femoral component with circumferential porous coating: an autopsy study of 5 femurs.

This autopsy study analyzed the migration of polyethylene wear debris adjacent to uncemented femoral components with circumferential porous coating. Five femoral specimens retrieved at autopsy from 3 patients were investigated. Two stems were 40% porous coated, 2 were 80% porous coated, and 1 was 100% porous coated. The implants' time in situ ranged from 53 to 132 months (average, 94.8 months). All patients were followed clinically and radiographically until death. Radiographically, 3 of the stems were bone ingrown with proximal bone loss, 1 stem was mainly fibrous encapsulated, and 1 stem was completely fibrous encapsulated. Histologic examination of bone adjacent to the middle and distal sections of the femoral implant revealed no polyethylene wear debris or granulation tissue in any of the specimens. In 2 bone-ingrown cases, a small number of polyethylene particles and small areas of granulation tissue were present at the proximal level. This granulation tissue, however, did not cause major osteolysis. The findings in this study imply that circumferential porous coating of cementless femoral components could prevent distal migration of polyethylene wear debris along the bone-implant interface in both bone-ingrown and fibrous-encapsulated femoral implants.

Osseointegration of cemented and noncemented implants in artificial hip replacement: long-term findings in man.

Implant fixation is of utmost importance for pain-free function of endoprostheses. Primary fixation is achieved during implantation, whereas secondary fixation is a result of repair and bone remodelling during the healing process comparable to fracture healing. The chronologic course of the healing process follows three overlapping phases: (i) an initial phase with destruction and necroses of bone, (ii) a phase of repair with integration of the implant into the bone, and (iii) a phase of stabilization of the permanent implant bed with adaptation to load transfer and possible reactions to irritations of the interface like sepsis, mechanical instability, corrosion and degradation of implant materials, and wear products from articulating and anchoring surfaces.

Unsuccessful surgical treatment of hip dislocation in congenital sensory neuropathy with anhidrosis. A case report.

A six-year-old girl with congenital sensory neuropathy with anhidrosis (CSNA) presented with bilateral hip dysplasia and subluxation on the right side. Conservative treatment of the hips by closed reduction and a plaster cast was unsuccessful. When aged seven years the patient had an intertrochanteric varus rotation osteotomy on the right side, but subluxation was again evident after five months. A Salter-type pelvic osteotomy was carried out followed by immobilisation, but one year later subluxation was present in the right hip and dislocation in the left. At the age of nine years, the right femoral head resembled a Charcot joint, although walking ability was preserved. In patients with CSNA, surgery may not always be advisable.

Longitudinal limb deficiencies and the sclerotomes. An analysis of 378 dysmelic malformations induced by thalidomide.

The pathogenesis of longitudinal reduction deformities of the limbs, or dysmelia, is still a matter of debate. Their morphological pattern was defined from a large collection of radiographs of children with dysmelia following the thalidomide disaster. We compared radiographs of 378 of these limbs with the sclerotomes which are areas of segmental sensory innervation of the limb skeleton defined by the radiation of referred pain. The pattern of dysmelia matched the sclerotomes closely in 279 limbs (73.5%). The principles of skeletal reduction in dysmelia are explained by the arrangement of the sclerotomes. The congruence between two separate and independent data sets shows that both patterns are expressions of the underlying segmental sensory innervation of the skeleton, and that the sensory nervous system is involved in the process of limb morphogenesis and teratogenesis.

Centralization of the femoral component in cemented hip arthroplasty using guided stem insertion.

In order to improve the positioning of the stem within the femur, to centralize it within the cement and to achieve a complete and homogeneous cement mantle, a new hip endoprosthesis with guided stem insertion was developed. The femoral component has a longitudinal channel that takes up a guidewire which directs it during insertion into the centre. The guidewire is attached to the cement stopper which is positioned in the marrow cavity before applying the bone cement. The first 100 endoprostheses of this type with an observation period of at least 6 years were assessed radiologically and clinically. The clinical evaluation according to the hip scores of Merle d'Aubigne and Harris revealed a marked improvement between preoperative and postoperative values for all criteria. On radiological assessment 94% of the stems had a neutral position within the femur; 98% of the stems were found to be ideally centred within the cement distally, 80% distally and proximally; 74% of the cement cuffs had a complete and homogeneous cement layer between 2 and 5 mm medially and laterally, while 25% had partially a dimension of more than 5 mm, predominantly proximally. In only 3 cases was one part of the cement mantle found to be less than 2 mm. The radiological follow-up was also documented according to the delineated zones of Gruen. It revealed zonal radiolucent lines in 15 cases, combined in 11 cases with reactive lines, never extending up to 4 zones out of 14. Five prostheses had subsided moderately between 2 and 3 mm, and only one 8 mm. None of these radiological signs was associated with clinical symptoms. There were five cement fractures. Two stems were symptomatic, radiologically loose and revised. Beside these two cases of aseptic loosening there was one septic case, so that in total 97% of the implants are still functioning well.

An oblong revision cup for large acetabular defects: design rationale and two- to seven-year follow-up.

Loosening and migration of acetabular components often lead to extensive bony defects with an elongated, oval acetabular cavity. In these cases standard implants will not reestablish and maintain sufficient stability without leaving bone defects or using massive bone grafts or excess cement and additional metal rings or shells, disadvantages that are overcome by using an oblong revision cup without cement. The titanium shell is available in different sizes, is screwed to the autochthonous acetabular bone and houses an oblong polyethylene inlay, designed to reestablish the normal anatomic hip center. Of 109 consecutive revision cups, 102, implanted for American Academy of Orthopaedic Surgeons (AAOS) defects types I-IV, were followed up clinically and radiologically for 2 to 7 years (mean, 3.6 years). Primary stability was achieved in all cases. In 40% no bone grafting was necessary at all. The radiological follow-up revealed good remodeling of the surrounding bone and osseointegration of the implants. Zonal radiolucent lines, always smaller than 2 mm, were seen in 18 cases, only once completely and in only 5 cases partially progressing. Six cups migrated slightly (< or =2 mm), two moderately (3-5 mm), all without clinical symptoms, and two more than 5 mm. Migration and radiolucencies were mainly seen in patients with allografts and major defects, which indicates that bone ingrowth appears more unlikely in such cases. Few asymptomatic cases showed zonal sclerotic lines. There were two aseptic loosenings, one in a case with pelvic discontinuity, the other in a patient with severe rheumatoid arthritis following two previous revisions. Survivorship analysis based on implant removal because of aseptic loosening as the endpoint shows a cumulative success rate of 98.1% at 8 years.

Photopenia in chronic vertebral osteomyelitis with technetium-99m-antigranulocyte antibody (BW 250/183).

UNLABELLED: Photon-deficient areas in 99mTc/111 in white blood cell (WBC) images for diagnosing vertebral osteomyelitis have been published often. This study retrospectively evaluated whether the use of 99mTc-labeled monoclonal antigranulocyte antibodies (BW 250/183) is superior to WBC and whether it offers higher specificity. METHODS: The study included 81 patients (46 men, 35 women; mean age 55 +/- 2 yr; from 1989 to 1995) with clinically suspected vertebral osteomyelitis who underwent scintigraphic imaging after intravenous injection of 555 MBq 99mTc-labeled monoclonal antigranulocyte antibodies. Forty patients suffered from osteomyelitis (20 men, 20 women; mean age 56 +/- 6 yr), 6 patients had metastases, 28 patients had spondylosis and disk herniation and 5 patients vertebral compression fractures. Diagnosis was not histologically verified in 2 patients. Planar imaging was performed at 4 and 24 hr postinjection. Histology of osteomyelitis was available in 30 patients, clinical follow-up in 10 patients. Visual uptake scores and quantitative uptake scores of the suspected areas were calculated. The results were compared to a semiquantitative histological score (high, medium, low grade) as well as to the scintigraphic scores. RESULTS: Scintigraphy showed photopenia in all patients with histologically proven vertebral osteomyelitis, independent of the grade of infection. A quantitative evaluation of 4 and 24 hr postinjection demonstrated a 58% increase of the uptake score in cases of histologically proven high-grade infections. This increase was seen predominantly in the thoracic spine but not in lumbar spine. All nonosseous paravertebral abscesses (n = 2) showed positive images and an increasing uptake over 24 hr. CONCLUSION: Paravertebral soft tissue infections can be differentiated excellently, whereas vertebral osteomyelitis, vertebral tumors or fractures can be localized, but no differentiation is possible.

Clinical wear behaviour of ultra-high molecular weight polyethylene cups paired with metal and ceramic ball heads in comparison to metal-on-metal pairings of hip joint replacements.

In the course of 30 years of hip endoprosthetics, a number of material combinations for the cups and balls of total hip prostheses have proven successful under clinical conditions. Favourably priced hip prostheses with polyethylene cups and metal balls are available for older patients with a moderate range of activity. Polyethylene wear of 100-300 microns/year is to be expected with these models. Ceramic balls (aluminium oxide for diameters 32 and 28 mm and zirconium oxide for 22 mm) paired with polyethylene cups are recommended for patients with a life expectancy of 10 to 20 years, because the expected polyethylene wear rate with this material combination is only 50-150 microns/year. In other words, the life cycle of the polyethylene cup is doubled, when it is paired with a ceramic ball. A similar polyethylene wear rate is also to be expected with oxygen-deep-hardened TiAlNb metal balls, which are currently the subject of a clinical field study. Last but not least, CoCrMoC metal-metal and Al2O3 ceramic ceramic pairings, which have the lowest wear rate of 2-20 microns/year, are available for highly active patients with a life expectancy of more than 20 years. As far as the cup-ball pairing is concerned and under the current pressure of costs, the surgeon should be able to select the optimum hip prosthesis model for every patient from these three categories.

Radiosynoviorthesis with rhenium-186 in rheumatoid arthritis: a prospective study of three treatment regimens.

The aim of this study was to evaluate the efficiency of radiation synovectomy with rhenium-186 in rheumatoid arthritis. In this prospective, randomized trial we compared three different treatment regimens for shoulder, elbow, wrist, hip and ankle joints: group 1, injection of rhenium-186; group 2, injection of rhenium-186 in combination with triamcinolone hexacetonide; group 3, injection of triamcinolone hexacetonide alone. Each treatment group included 50 joints. Patients included in the study had to fulfil the following criteria: (1) they had to have a diagnosis of rheumatoid arthritis (ARA criteria 1988), (2) their disease-modifying drug had to be methotrexate, started at least 6 months prior to injection therapy and given for the entire study time, (3) their nonsteroidal anti-inflammatory drug had to be diclofenac given at a dose of 150 mg/day or less and (4) they were also given prednisolone at a dose of 7.5 mg/day or less. After 3 years of follow-up, 79 joints met these criteria, i.e. 71 joints were excluded from the study: 26 joints because the patients changed the disease-modifying drug (12 joints from group 1, 4 joints from group 2 and 10 joints from group 3); 45 joints because of recurrent synovitis and second-stage treatment (21 joints from group 1, 5 joints from group 2 and 19 joints from group 3). During the follow-up period, joints were assessed for pain, synovitis, joint motion and stage of radiological destruction. Best clinical results and slowest progression in radiological destruction were achieved with the combined injection of rhenium-186 and triamcinolone hexacetonide. Therefore, we recommend this treatment for articulosynovitis with the exception of severe forms, the latter because of the effective penetration range of rhenium-186.

Crevice corrosion of cemented titanium alloy stems in total hip replacements.

Twenty-eight cemented Müller straight femoral stems of titanium forged alloys were mainly revised for causing pain in the patient. The pain pattern differed from aseptic loosening and pain recurred only 14.5 months on average after implantation. The character of pain was dull, permanent, and increased at rest. Some patients reported pain relief while walking. Revisions were performed on average 25.5 months after primary implantation. Data from medical records, radiographs, histology of tissues taken at revision surgery, intraoperative pH measurements, examination of retrieved stems and bone cement fragments were gathered. In the radiographs debonding was visible only in 3 cases; a spindle shaped thickening of the femora occurred 9 months on average after recurrence of pain. After a further 11 months (average), scalloping osteolyses appeared. Abraded particles like metallic titanium alloy, titanium corrosion products, polymethylmethacrylate, xray contrast medium, and polyethylene were detected. Metallic particles dominated in the joint capsule whereas more corrosion products impregnated the cement to bone interface. The distal surfaces of the stems were corroded at a higher rate, whereas the proximal regions more often were subject to abrasion. Measurements of the pH of the corroded stems revealed values of high acidity. Recurrence of pain and subperiosteal apposition of bone are due to diffusion of acid; subsequent scalloping osteolyses develop due to particle induced foreign body granulomas. The mechanism of crevice corrosion of cemented titanium based alloys does not seem applicable to cobalt and iron based implant alloys. Titanium alloys can no longer be recommended for cementation, but are as safe as ever for anchorage without cement.

Wear behavior and histopathology of classic cemented metal on metal hip endoprostheses.

The authors reviewed their collection of retrieved all metal hip joints (9 McKee-Farrar, 7 Müller, and 3 Huggler type prostheses) and tissues from the joint capsules and implant beds. The amount of wear was measured, and the total volume was calculated. The tissues were analyzed by atomic absorption spectral analysis or inductively coupled plasma mass spectrometry and examined by light and scanning electron microscopy. The size of particles was measured with a texture analysis system. The articulating surfaces showed many delicate scratches which represent normal wear. The calculated annual wear averaged approximately 5 mm3 per year, which is low compared with polyethylene. The cellular reaction to metal wear particles was regarded as mild. The cellular reaction to scattered and worn bone cement was always more pronounced than to metallic debris. Scanning electron microscopy confirmed the irregular shapes and mostly submicron size of the metal particles. The analytically detected metal content of the periarticular tissue was relatively low and in accordance with the wear measurements from the articulating surfaces. The excess of chromium in the tissues is discussed in the light of the elimination of cobalt as well as the relation between elements representing either corrosion products or elements still bound in wear particles.

[Clinical Wear Behaviour of UHMW Polyethylene Cups Paired with Metal and Ceramic Ball Heads in Comparison to Metal-on-Metal Pairings of Hip Joint Replacements.]. / Klinisches Verschleissverhalten von UHMW Polyethylen Pfannen in Paarung mit Metall und Keramik Kugeln im Vergleich zur Metallgegen-Metall Paarung beim Hüftgelenkersatz.

In the course of 30 years' hip endoprosthetics, a number of material combinations for the cups and balls of total hip prostheses have proven successful under clinical conditions. Favourably priced hip prostheses with polyethylene cups and metal balls are available for very old patients with a moderate range of activity. Polyethylene wear of 100-300 microm per year is to be expected with these models. Ceramic balls (aluminium oxide for diameters 32 and 28 mm and zirconium oxide for 22 mm) paired with polyethylene cups are recommended for patients with a life expectancy of 10 to 20 years, because the expected polyethylene wear rate with this material combination is only 50-150 microm per annum. In other words, the life cycle of the polyethylene cup is doubled, when it is paired with a ceramic ball. A similar polyethylene wear rate is also to be expected with oxygen-deephardened TiAlNb metal balls, which are currently the subject of a clinical field study. Last but not least, CoCrMoC metal/metal and AI2O3 ceramic/ceramic pairings, which have the lowest wear rate of 2 to 20 microm/year. are available for highly active patients with a life expectancy of more than 20 years. As far as the cup/ball pairing is concerned and under the current pressure of costs, the surgeon should be able to select the optimum hip prosthesis model for every patient from these three categories.