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Severe metallosis due to abnormal abrasion of the femoral head in a dual bearing hip prosthesis
S e v e r e M e t a l l o s i s D u e to A b n o r m a l A b r a s i o n o f t h e F e m o r a l H e a d in a D u a l B e a r i n g H i p Prosthesis A Case Report Yasutaka Matsuda,
MD,* Takao Yamamuro,
Yoshitaka Matsusue,
MD,* Ryuichi Kasai, MD,*
MD,* and Hideo Okumura,
MDt
Abstract: The authors report on a patient with a case of severe metallosis due to an abnormal abrasion of the femoral head. A primary arthroplasty was performed using a dual bearing hip prosthesis with acetabular bone grafting by ceramic screws. At the time of the revision surgery the synovia was black, and an analysis using a scanning electron microscope and scanning electron microscope-electron probe micro-analyzer revealed numerous small particles of small alumina ceramic on the inner surface of the bearing insert of high-density polyethylene. These particles, which came from the broken ceramic screws due to proximal migration of the prosthesis, scraped the femoral head away. A line and area analysis of the black synovia revealed that the synovia contained metal particles of a cobalt-chromium alloy as well as a cobalt ion. The patient's serum showed elevated concentrations of cobalt, chromium, and molybdenum that dramatically reduced 2 months after the revision surgery. Key words: metallosis, total hip arthroplasty, alumina ceramic, dual bearing hip prosthesis, Co-Cr alloy.
Metallosis, defined as aseptic fibrosis, local necrosis, or loosening of a device due to metallic corrosion and the release of wear debris, 5 has often been experienced in patients with m e t a l - o n - m e t a l total hip arthroplasty (THA), such as the McKee-Farrar prosthesis.ll Recently, h o w e v e r , because m a n y prostheses have adopted the m e t a l - o n - p o l y m e r or ceramic-on-polymer design, metallosis is rarely encountered. There was a recent report of a case in which abrasion of a titanium alloy femoral head occurred without corresponding loosening, 5 and several reports have identified metallosis as a contribut-
ing factor in the clinical failure of the THA. However, abrasions of cobalt-chromium (Co- Cr) femoral heads in metal-on-polymer THA is very rare. We report a case of THA with severe metallosis. The Co-Cr femoral head was w o r n up to 2.09 mm, and particles of alumina ceramic, from the screws used for fixation of the bone graft in the dysplastic acetabulum, were embedded into the inner surface of the bearing insert of high-density p o l y e t h y l e n e (HDP).
Case Report From the *Department of Orthopaedic Surgery, Faculty of Medicine, Kyoto University, Kyoto, Japan, and tthe Department of Orthopaedic Surgery, Faculty of Medicine, Ehime University, Ehime, Japan. Reprint requests: Yasutaka Matsuda, Department of Orthopaedic Surgery, Faculty of Medicine, KyotoUniversity, 54 Kawaharacho, Shogoin, Sakyo-ku, Kyoto, 606, Japan.
A 22-year-old w o m a n experienced pain in her left hip joint in January 1983 and was diagnosed as having osteoarthritis of the hip joint due to dysplasia in
439
440
The Journal of Arthroplasty Vol. 7 Supplement 1992
Fig. 1. Anteroposterior radiograph of the hip joint. (A) On first admission, deformity of the hip joint was remarkable. (B) Immediately after the first operation. (C) Before revision, proximal migration of the prosthesis was noted and the fractured ceramic screw migrated into the hip joint. The prosthesis became loose.
the acetabulum. As the severity of pain increased she became unable to walk. In May 1984, she had a dual bearing hip prosthesis made of Co-Cr alloy (Bateman UPF, 3M, Minnesota) was implanted and a bone graft was performed in the dysplastic acetabulum using two ceramic screws made of monocrystal alumina ceramic (Sapphire Screw, Kyocera, Kyoto, Japan). Fixation of the femoral stem was accomplished using the press-fit technique without bone cement. Her postoperative course was uneventful and the pain disappeared completely with good range of motion. However, radiographs taken in February 1990 revealed a fracture of the ceramic screw due to proximal migration of the outer head and loosening of the femoral prosthesis. A revision arthroplasty was performed in May 1990 (Fig. 1). During surgery the synovia was found to be black and loosening of the femoral stem was considerable. The femoral head was worn to the shape of a rugby ball. The bearing insert of HDP showed wear of 0.51 mm and had numerous small particles of alumina ceramic on its inner surface. A mixture of autogenous and artificial bone (apatite-wollastonite containing glass ceramic, Nippon Electric Glass, Otsu, Japan) as well as fibrin glue were applied to the bone defect of the acetabulum. The Bateman UPF prosthesis was replaced by a ceramic-on-polymer dual bearing prosthesis made of titanium alloy (Physio-Hip System, Kyocera, Kyoto, Japan). Six months after surgery the
pain in her hip joint disappeared completely and she was able to walk again.
Examination of the Specimen The femoral head was worn up to 2:09 m m on the weight-bearing surface, but the bearing insert of HDF revealed wear of 0.51 mm. On the inner surface of the bearing insert, numerous small particles were observed (Fig. 2). The outer head showed some striation due to contact with the screw. Histologically, numerous extracellular particles were found in the black-stained synovia, and the histiocytes contained the same particles intracellularly. A low grade of inflammation was confirmed (Fig. 3). Scanning electron microscopic (SEM) examination of the inner surface of the bearing insert revealed fragments with sharp corners attached to the bearing insert. A line analysis of these particles by scanning electron microscope-electron probe micro-analyzer (SEM-EPMA) displayed a single peak of aluminum. As the ceramic screw was the only item that contained aluminum around her hip joint, these fragments were considered to be alumina ceramic (Fig. 4). Macroscopically, though the outer surface of the pseudocapsule was white, the inner surface (the synovia) was stained black. The boundary line between the white and black areas was relatively clear. When a line analysis of the black synovia was performed, not only were many peaks of cobalt (Co), chromium
Severe Metallosis Due to Abnormal Abrasion of Femoral Head -
-
• 22¢~
Matsuda et al. .................
~'\
Fig. 2. (A,B) The femoral head. Wear of 2.09 m m was observed on the weight-bearing surface. (C,D) The bearing insert. Wear of 0.51 m m was observed.
A
\
(ram)
--..
B =
"
~
- 36.12
/
i i 51
"
I C
Fig. 3. Photomicrograph of the black synovia. There are numerous metal particles extracellularly and histiocytes that contain metal particles intracellularly. (hematoxylin and eosin, original magnification x 200).
D
441
442
The Journal of Arthroplasty Vol. 7 Supplement 1992
J
SEM
A k-RAY:
0
....I0 . keLJ
Live:
50s Preset:
Real:
55s
.....
50s Remainin_q:
0 ~s
9% Oea(i
AI2
L 5.020
keg lO. I K eh 512= 6 ctsl O05-R . . . . . . . . . . .
B
EPMA
Fig. 4. (A) Scanning electron micrograph of the inner surface of the HDP. Fragments with sharp corners are embedded into the inner surface of the bearing insert. (B) An analysis of the EPMA of the fragment. The peak of aluminium is observed.
(Cr), and m o l y b d e n u m (Mo) ~found, but these peaks also corresponded to each other. The small particles in the black synovia were confirmed to be of Co-Cr alloy, because the particles and the femoral head had a similar metallic composition (Fig. 5). In addition, a SEM-EPMA line analysis traversing the boundary line between the black and white areas revealed that there were few peaks of Co in the white area, with
the content of Co decreasing while progressing away from the boundary line. Thus the process of releasing Co ions was confirmed (Fig. 6). An inductively coupled plasma-mass spectrometer (ICP-Mass, VGE, Winsford, England) was used to analyze the metal content of the patient's serum. Before operation the serum contained elevated concentrations of Co (3.6ppm), Cr (1.9ppm), and Mo
Severe Metallosis Due to Abnormal Abrasion of Femoral Head
•
Matsuda et al.
443
zs[ 20-
@
15~
t
5r
I
Fig. 5. Line analysis of the black synovia by SEM-EPMA. The peaks of Co, Cr, and Mo correspond to each other.
Y,
0.5. ~; 0
Fe so~m
t
I
I
I
I
I
I
I
i
(0.4ppm), although the patient did not have any effects due to these metals. However, 2 m o n t h s after surgery these values decreased r e m a r k a b l y to Co (0.03ppm), Cr (0.09ppm), and Mo (0.6ppm). Discussion W h e n w e a r might occur between the Co-Cr alloy and HDP in a THA, HDP should w e a r out first. In this case, the femoral head of the Co-Cr alloy was worn, a l t h o u g h the bearing insert of HDP s h o w e d little wear. A l u m i n u m was found to exist on the inner surface of the bearing insert through SEM and SEM-
i
i
i
EPMA analyses. As oxygen has too small an atomic weight to detect by using SEM-EPMA, the a l u m i n u m on the inner surface of the bearing insert proved to be alumina ceramic f r o m the fractured ceramic screw. Thinking of the clinical course, the process of abrasion of the femoral h e a d was assumed to have occurred in the following way. At first, the outer head came in direct contact with the ceramic screw due to proximal migration of the prosthesis. Then the ceramic screw broke and the particles of a l u m i n a ceramic were scattered into the joint. These particles were sucked into the articulating interface b e t w e e n the femoral head and the bearing insert and t h e n
444
The Journal of Arthroplasty Vol. 7 Supplement 1992
. . . . . . . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
i,-Flr?1- r
.
F---F. . . .
,]] '!! I
li ,//ii 50 pm
_
~,
F-,.
@
(X,)
1.0.
White
10
06
0 8
0.6
,l t
!,,1 :
04
0.4 ::).2 0.2
; - . . . . . . . . . . . . T ........ T ..... !:l-.-_~
.....
i .H
J
_
Fig. 6. Analysis of SEM-EPMA traversing the black and white area. There are many peaks of Co in the black area, however, peaks of Co are scarcely seen in the white area. The concentration of Co gradually decreases while progressing away from the boundary line.
embedded into the inner surface of the bearing insert. Finally, these particles scraped" the femoral head away, like sand paper, up to 2.09 mm. The black synovia was found to contain metal particles, and the white pseudocapsule contained few particles of metal. The line analysis, traversing the boundary line between the black and white areas, revealed that the concentration of Co decreased while progressing away from the boundary line, thus ions of Co became disengaged from the metal particles in the black synovia. Preoperatively, the concentrations of Co, Cr, and Mo increased in the patient's serum in this manner. Bartolozzi and Black 2 and Black et al. 4 reported postoperative elevated metal content in the serum of patients w h o had metal-on-polymer THAs fixated by bone cement. All of the released metals could have biological effects on the h u m a n body according to dosage, although the patients have revealed no sign of such effects to date. These effects are classified into three categories: metabolic, immunogenic, and oncogenic. 3 Though Co and Cr are essential in sugar metabolism and vitamin Blx synthesis, respectively, these
metals could b e c o m e toxic d e p e n d i n g o n the amount. Aluminum competes with magnesium in polymerizing tubulin, one of the primary structural proteins in the central and peripheral nervous system. The state of a l u m i n u m - r i c h / m a g n e s i u m - p o o r serum could cause disorders of the nervous system. 9 As biomaterials they should be used very carefully. Cobalt, c h r o m i u m (in b o t h + 3 and + 6 valence states), and nickel (Ni) are haptens, which are capable of binding with proteins to form i m m u n e complexes. 7 Several reports have asserted the clinical immunologic effects of nickel. Postoker et al. 13 reported dermatitis due to o r t h o p a e d i c implants m a d e of stainless steel. Kumar et al. 8 reported a case of a failed total knee arthroplasty due to metal hypersensitivity. Sax 15 reported that Co, Cr ( + 6 valence state), and Ni proved to be oncogenic in animal studies. In a review of the literature, we found seven reports of sarcomas resulting from total joint arthroplasties. ~,6, 1o,i2,14,16,17 The incidence of sarcomas m a y increase in the future. We should choose less oncogenic materials for orthopaedic implants. As alumina ceramic has good mechanical strength as well as good biocompatibility, recent hip
Severe Metallosis Due to Abnormal Abrasion of Femoral Head
p r o s t h e s e s h a v e a d o p t e d c e r a m i c s . H o w e v e r , cer a m i c s t e n d to b r e a k b e c a u s e of t h e i r b r i t t l e n e s s , sometimes creating numerous small fragments. In t h e case r e p o r t e d here, b e c a u s e small particles of alum i n a c e r a m i c w e r e s u c k e d into t h e a r t i c u l a t i n g interface, severe m e t a l l o s i s a n d t h e release of m e t a l l i c ions i n t o t h e p a t i e n t ' s s e r u m o c c u r r e d . C e r a m i c screws s h o u l d b e u s e d carefully w h e n fixing b o n e grafts in t h e dysplastic a c e t a b u l u m , e s p e c i a l l y in c o m b i n a t i o n w i t h a d u a l b e a r i n g h i p prosthesis, w h i c h m a y m i grate p r o x i m a l l y .
10.
References
11.
1. Bago-Granell J, Aguirre- Canyadell M, Nardi J, Tallada N: Malignant fibrous histiocytoma of bone at the site of a total hip arthroplasty. J Bone Joint Surg 66B:38, 1984 2. Bartolozzi A, Black J: Chromium concentrations in serum, blood clot, and urine from patients following total hip arthroplasty. Biomaterials 6:2, 1985 3. Black J: Does corrosion m a t t e r (editorial). J Bone Joint Surg 70B:517, 1988 4. Black J, Maitin EC, Gelman H, Morris DM: Serum concentrations of chromium, cobalt, and nickel after total hip replacement: a six month study. Biomaterials 4:160, 1983 5. Black J, Sherk H, Bonini J e t al: Metallosis associated with a stable titanium-alloy femoral c o m p o n e n t in total hip replacement. J Bone Joint Surg 72A: 126, 1990 6. Brien WW, Salvati ED, Healey JH et ah Osteogenic
7.
8.
9.
12.
13.
14.
15. 16.
17.
•
Matsuda et al.
445
sarcoma arising in the area of a total hip replacement. J Bone Joint Surg 72A:1097, 1990 Fregert S, Rorsman H: Allergy to chromium, nickel, and cobalt. Acta Derm Venereol (Stockh) 46: 144, 1966 Kumar P, Bryan C, Bowler J, D'Ambrosia R: Failed total knee prosthesis secondary to metal hypersensitivity. Orthopedics 6:1459, I983 MacDonald TL, Humphreys WG, Martin RB: Promotion of tubulin assembly by aluminium ion in vitro. Science 236:183, 1987 Martin A, Bauer TW, Manley MT, Marks KE: Osteosarcoma at the site of total hip replacement. J Bone Joint Surg 70A:I561, 1988 McKee GK: Total hip replacement. Sector, London, 1971 Penman HG, Ring P: Osteosarcoma in association with total hip replacement. J Bone Joint Surg 66B:632, 1984 Postoker G, Robin J, Blamoutier J et ah Dermatitis due to orthopaedic implants. J Bone Joint Surg 69A: 1408, i987 Ryu RKN, Bovill EG Jr, Skinner H, Murray WR: Soft tissue sarcoma associated with aluminium oxide ceramic total hip arthroplasty. Clin Orthop 216:207, 1987 Sax NI: Cancer causing chemicals. Van Norstrand Reinhold, New York, 1981 Swann M: Malignant soft tissue tumor at the site of a total hip replacement. J Bone Joint Surg 66B:629, 1984 Weber PC: Epitheloid sarcoma in association with total knee replacement. J Bone Joint Surg 68B:824, 1986
MD,* Takao Yamamuro,
Yoshitaka Matsusue,
MD,* Ryuichi Kasai, MD,*
MD,* and Hideo Okumura,
MDt
Abstract: The authors report on a patient with a case of severe metallosis due to an abnormal abrasion of the femoral head. A primary arthroplasty was performed using a dual bearing hip prosthesis with acetabular bone grafting by ceramic screws. At the time of the revision surgery the synovia was black, and an analysis using a scanning electron microscope and scanning electron microscope-electron probe micro-analyzer revealed numerous small particles of small alumina ceramic on the inner surface of the bearing insert of high-density polyethylene. These particles, which came from the broken ceramic screws due to proximal migration of the prosthesis, scraped the femoral head away. A line and area analysis of the black synovia revealed that the synovia contained metal particles of a cobalt-chromium alloy as well as a cobalt ion. The patient's serum showed elevated concentrations of cobalt, chromium, and molybdenum that dramatically reduced 2 months after the revision surgery. Key words: metallosis, total hip arthroplasty, alumina ceramic, dual bearing hip prosthesis, Co-Cr alloy.
Metallosis, defined as aseptic fibrosis, local necrosis, or loosening of a device due to metallic corrosion and the release of wear debris, 5 has often been experienced in patients with m e t a l - o n - m e t a l total hip arthroplasty (THA), such as the McKee-Farrar prosthesis.ll Recently, h o w e v e r , because m a n y prostheses have adopted the m e t a l - o n - p o l y m e r or ceramic-on-polymer design, metallosis is rarely encountered. There was a recent report of a case in which abrasion of a titanium alloy femoral head occurred without corresponding loosening, 5 and several reports have identified metallosis as a contribut-
ing factor in the clinical failure of the THA. However, abrasions of cobalt-chromium (Co- Cr) femoral heads in metal-on-polymer THA is very rare. We report a case of THA with severe metallosis. The Co-Cr femoral head was w o r n up to 2.09 mm, and particles of alumina ceramic, from the screws used for fixation of the bone graft in the dysplastic acetabulum, were embedded into the inner surface of the bearing insert of high-density p o l y e t h y l e n e (HDP).
Case Report From the *Department of Orthopaedic Surgery, Faculty of Medicine, Kyoto University, Kyoto, Japan, and tthe Department of Orthopaedic Surgery, Faculty of Medicine, Ehime University, Ehime, Japan. Reprint requests: Yasutaka Matsuda, Department of Orthopaedic Surgery, Faculty of Medicine, KyotoUniversity, 54 Kawaharacho, Shogoin, Sakyo-ku, Kyoto, 606, Japan.
A 22-year-old w o m a n experienced pain in her left hip joint in January 1983 and was diagnosed as having osteoarthritis of the hip joint due to dysplasia in
439
440
The Journal of Arthroplasty Vol. 7 Supplement 1992
Fig. 1. Anteroposterior radiograph of the hip joint. (A) On first admission, deformity of the hip joint was remarkable. (B) Immediately after the first operation. (C) Before revision, proximal migration of the prosthesis was noted and the fractured ceramic screw migrated into the hip joint. The prosthesis became loose.
the acetabulum. As the severity of pain increased she became unable to walk. In May 1984, she had a dual bearing hip prosthesis made of Co-Cr alloy (Bateman UPF, 3M, Minnesota) was implanted and a bone graft was performed in the dysplastic acetabulum using two ceramic screws made of monocrystal alumina ceramic (Sapphire Screw, Kyocera, Kyoto, Japan). Fixation of the femoral stem was accomplished using the press-fit technique without bone cement. Her postoperative course was uneventful and the pain disappeared completely with good range of motion. However, radiographs taken in February 1990 revealed a fracture of the ceramic screw due to proximal migration of the outer head and loosening of the femoral prosthesis. A revision arthroplasty was performed in May 1990 (Fig. 1). During surgery the synovia was found to be black and loosening of the femoral stem was considerable. The femoral head was worn to the shape of a rugby ball. The bearing insert of HDP showed wear of 0.51 mm and had numerous small particles of alumina ceramic on its inner surface. A mixture of autogenous and artificial bone (apatite-wollastonite containing glass ceramic, Nippon Electric Glass, Otsu, Japan) as well as fibrin glue were applied to the bone defect of the acetabulum. The Bateman UPF prosthesis was replaced by a ceramic-on-polymer dual bearing prosthesis made of titanium alloy (Physio-Hip System, Kyocera, Kyoto, Japan). Six months after surgery the
pain in her hip joint disappeared completely and she was able to walk again.
Examination of the Specimen The femoral head was worn up to 2:09 m m on the weight-bearing surface, but the bearing insert of HDF revealed wear of 0.51 mm. On the inner surface of the bearing insert, numerous small particles were observed (Fig. 2). The outer head showed some striation due to contact with the screw. Histologically, numerous extracellular particles were found in the black-stained synovia, and the histiocytes contained the same particles intracellularly. A low grade of inflammation was confirmed (Fig. 3). Scanning electron microscopic (SEM) examination of the inner surface of the bearing insert revealed fragments with sharp corners attached to the bearing insert. A line analysis of these particles by scanning electron microscope-electron probe micro-analyzer (SEM-EPMA) displayed a single peak of aluminum. As the ceramic screw was the only item that contained aluminum around her hip joint, these fragments were considered to be alumina ceramic (Fig. 4). Macroscopically, though the outer surface of the pseudocapsule was white, the inner surface (the synovia) was stained black. The boundary line between the white and black areas was relatively clear. When a line analysis of the black synovia was performed, not only were many peaks of cobalt (Co), chromium
Severe Metallosis Due to Abnormal Abrasion of Femoral Head -
-
• 22¢~
Matsuda et al. .................
~'\
Fig. 2. (A,B) The femoral head. Wear of 2.09 m m was observed on the weight-bearing surface. (C,D) The bearing insert. Wear of 0.51 m m was observed.
A
\
(ram)
--..
B =
"
~
- 36.12
/
i i 51
"
I C
Fig. 3. Photomicrograph of the black synovia. There are numerous metal particles extracellularly and histiocytes that contain metal particles intracellularly. (hematoxylin and eosin, original magnification x 200).
D
441
442
The Journal of Arthroplasty Vol. 7 Supplement 1992
J
SEM
A k-RAY:
0
....I0 . keLJ
Live:
50s Preset:
Real:
55s
.....
50s Remainin_q:
0 ~s
9% Oea(i
AI2
L 5.020
keg lO. I K eh 512= 6 ctsl O05-R . . . . . . . . . . .
B
EPMA
Fig. 4. (A) Scanning electron micrograph of the inner surface of the HDP. Fragments with sharp corners are embedded into the inner surface of the bearing insert. (B) An analysis of the EPMA of the fragment. The peak of aluminium is observed.
(Cr), and m o l y b d e n u m (Mo) ~found, but these peaks also corresponded to each other. The small particles in the black synovia were confirmed to be of Co-Cr alloy, because the particles and the femoral head had a similar metallic composition (Fig. 5). In addition, a SEM-EPMA line analysis traversing the boundary line between the black and white areas revealed that there were few peaks of Co in the white area, with
the content of Co decreasing while progressing away from the boundary line. Thus the process of releasing Co ions was confirmed (Fig. 6). An inductively coupled plasma-mass spectrometer (ICP-Mass, VGE, Winsford, England) was used to analyze the metal content of the patient's serum. Before operation the serum contained elevated concentrations of Co (3.6ppm), Cr (1.9ppm), and Mo
Severe Metallosis Due to Abnormal Abrasion of Femoral Head
•
Matsuda et al.
443
zs[ 20-
@
15~
t
5r
I
Fig. 5. Line analysis of the black synovia by SEM-EPMA. The peaks of Co, Cr, and Mo correspond to each other.
Y,
0.5. ~; 0
Fe so~m
t
I
I
I
I
I
I
I
i
(0.4ppm), although the patient did not have any effects due to these metals. However, 2 m o n t h s after surgery these values decreased r e m a r k a b l y to Co (0.03ppm), Cr (0.09ppm), and Mo (0.6ppm). Discussion W h e n w e a r might occur between the Co-Cr alloy and HDP in a THA, HDP should w e a r out first. In this case, the femoral head of the Co-Cr alloy was worn, a l t h o u g h the bearing insert of HDP s h o w e d little wear. A l u m i n u m was found to exist on the inner surface of the bearing insert through SEM and SEM-
i
i
i
EPMA analyses. As oxygen has too small an atomic weight to detect by using SEM-EPMA, the a l u m i n u m on the inner surface of the bearing insert proved to be alumina ceramic f r o m the fractured ceramic screw. Thinking of the clinical course, the process of abrasion of the femoral h e a d was assumed to have occurred in the following way. At first, the outer head came in direct contact with the ceramic screw due to proximal migration of the prosthesis. Then the ceramic screw broke and the particles of a l u m i n a ceramic were scattered into the joint. These particles were sucked into the articulating interface b e t w e e n the femoral head and the bearing insert and t h e n
444
The Journal of Arthroplasty Vol. 7 Supplement 1992
. . . . . . . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
i,-Flr?1- r
.
F---F. . . .
,]] '!! I
li ,//ii 50 pm
_
~,
F-,.
@
(X,)
1.0.
White
10
06
0 8
0.6
,l t
!,,1 :
04
0.4 ::).2 0.2
; - . . . . . . . . . . . . T ........ T ..... !:l-.-_~
.....
i .H
J
_
Fig. 6. Analysis of SEM-EPMA traversing the black and white area. There are many peaks of Co in the black area, however, peaks of Co are scarcely seen in the white area. The concentration of Co gradually decreases while progressing away from the boundary line.
embedded into the inner surface of the bearing insert. Finally, these particles scraped" the femoral head away, like sand paper, up to 2.09 mm. The black synovia was found to contain metal particles, and the white pseudocapsule contained few particles of metal. The line analysis, traversing the boundary line between the black and white areas, revealed that the concentration of Co decreased while progressing away from the boundary line, thus ions of Co became disengaged from the metal particles in the black synovia. Preoperatively, the concentrations of Co, Cr, and Mo increased in the patient's serum in this manner. Bartolozzi and Black 2 and Black et al. 4 reported postoperative elevated metal content in the serum of patients w h o had metal-on-polymer THAs fixated by bone cement. All of the released metals could have biological effects on the h u m a n body according to dosage, although the patients have revealed no sign of such effects to date. These effects are classified into three categories: metabolic, immunogenic, and oncogenic. 3 Though Co and Cr are essential in sugar metabolism and vitamin Blx synthesis, respectively, these
metals could b e c o m e toxic d e p e n d i n g o n the amount. Aluminum competes with magnesium in polymerizing tubulin, one of the primary structural proteins in the central and peripheral nervous system. The state of a l u m i n u m - r i c h / m a g n e s i u m - p o o r serum could cause disorders of the nervous system. 9 As biomaterials they should be used very carefully. Cobalt, c h r o m i u m (in b o t h + 3 and + 6 valence states), and nickel (Ni) are haptens, which are capable of binding with proteins to form i m m u n e complexes. 7 Several reports have asserted the clinical immunologic effects of nickel. Postoker et al. 13 reported dermatitis due to o r t h o p a e d i c implants m a d e of stainless steel. Kumar et al. 8 reported a case of a failed total knee arthroplasty due to metal hypersensitivity. Sax 15 reported that Co, Cr ( + 6 valence state), and Ni proved to be oncogenic in animal studies. In a review of the literature, we found seven reports of sarcomas resulting from total joint arthroplasties. ~,6, 1o,i2,14,16,17 The incidence of sarcomas m a y increase in the future. We should choose less oncogenic materials for orthopaedic implants. As alumina ceramic has good mechanical strength as well as good biocompatibility, recent hip
Severe Metallosis Due to Abnormal Abrasion of Femoral Head
p r o s t h e s e s h a v e a d o p t e d c e r a m i c s . H o w e v e r , cer a m i c s t e n d to b r e a k b e c a u s e of t h e i r b r i t t l e n e s s , sometimes creating numerous small fragments. In t h e case r e p o r t e d here, b e c a u s e small particles of alum i n a c e r a m i c w e r e s u c k e d into t h e a r t i c u l a t i n g interface, severe m e t a l l o s i s a n d t h e release of m e t a l l i c ions i n t o t h e p a t i e n t ' s s e r u m o c c u r r e d . C e r a m i c screws s h o u l d b e u s e d carefully w h e n fixing b o n e grafts in t h e dysplastic a c e t a b u l u m , e s p e c i a l l y in c o m b i n a t i o n w i t h a d u a l b e a r i n g h i p prosthesis, w h i c h m a y m i grate p r o x i m a l l y .
10.
References
11.
1. Bago-Granell J, Aguirre- Canyadell M, Nardi J, Tallada N: Malignant fibrous histiocytoma of bone at the site of a total hip arthroplasty. J Bone Joint Surg 66B:38, 1984 2. Bartolozzi A, Black J: Chromium concentrations in serum, blood clot, and urine from patients following total hip arthroplasty. Biomaterials 6:2, 1985 3. Black J: Does corrosion m a t t e r (editorial). J Bone Joint Surg 70B:517, 1988 4. Black J, Maitin EC, Gelman H, Morris DM: Serum concentrations of chromium, cobalt, and nickel after total hip replacement: a six month study. Biomaterials 4:160, 1983 5. Black J, Sherk H, Bonini J e t al: Metallosis associated with a stable titanium-alloy femoral c o m p o n e n t in total hip replacement. J Bone Joint Surg 72A: 126, 1990 6. Brien WW, Salvati ED, Healey JH et ah Osteogenic
7.
8.
9.
12.
13.
14.
15. 16.
17.
•
Matsuda et al.
445
sarcoma arising in the area of a total hip replacement. J Bone Joint Surg 72A:1097, 1990 Fregert S, Rorsman H: Allergy to chromium, nickel, and cobalt. Acta Derm Venereol (Stockh) 46: 144, 1966 Kumar P, Bryan C, Bowler J, D'Ambrosia R: Failed total knee prosthesis secondary to metal hypersensitivity. Orthopedics 6:1459, I983 MacDonald TL, Humphreys WG, Martin RB: Promotion of tubulin assembly by aluminium ion in vitro. Science 236:183, 1987 Martin A, Bauer TW, Manley MT, Marks KE: Osteosarcoma at the site of total hip replacement. J Bone Joint Surg 70A:I561, 1988 McKee GK: Total hip replacement. Sector, London, 1971 Penman HG, Ring P: Osteosarcoma in association with total hip replacement. J Bone Joint Surg 66B:632, 1984 Postoker G, Robin J, Blamoutier J et ah Dermatitis due to orthopaedic implants. J Bone Joint Surg 69A: 1408, i987 Ryu RKN, Bovill EG Jr, Skinner H, Murray WR: Soft tissue sarcoma associated with aluminium oxide ceramic total hip arthroplasty. Clin Orthop 216:207, 1987 Sax NI: Cancer causing chemicals. Van Norstrand Reinhold, New York, 1981 Swann M: Malignant soft tissue tumor at the site of a total hip replacement. J Bone Joint Surg 66B:629, 1984 Weber PC: Epitheloid sarcoma in association with total knee replacement. J Bone Joint Surg 68B:824, 1986