471

ORIGINAL
Middle-term outcome and complications after primary total hip
arthroplasty using a contemporary titanium tapered wedge
cementless femoral stem
Yuto Sugimine1, Shunji Nakano1, Hitoshi Goto1, Ryosuke Sato1, Tetsuya Enishi2, Tomohiro Goto1, and Koichi Sairyo3
Department of Orthopedics, Tokushima Municipal Hospital, Tokushima, Japan, 2Department of Rehabilitation Medicine, Tokushima Municipal Hospital, Tokushima, Japan, 3Department of Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School,
Tokushima, Japan
1

Abstract : The purpose of this study is to evaluate the results and intraoperative or postoperative complicationsof primary total hip arthroplasty (THA) using a contemporary tapered wedge titanium femoral component. A
total of 213 THAs in 187 patients were followed up more than 5 years (mean, 102 months ; range, 60-150). The
mean age at surgery was 64.2 years (range, 20–89 years). These patients were clinically evaluated using the JOA
scoring system and radiographically host bone reactions around the implants, as well as femoral loosening. The
mean JOA score improved from 49 (range, 21–75) to 92 (range, 59–100). All 12 patients with poor results (JOA <75) coexisted with cerebral, spinal, joint, and musculoskeletal disorders. At the final follow-up, implant survival
was 100%. Complications occurred in 23 hips. They consisted of 12 hips with intra-operative fractures, 2 hips withsciatic nerve palsy, one hip with infections, 3 hips with recurrent dislocations, and 8 hips with aseptic cup loosening. In conclusion, we have shown excellent survival rate of the contemporary tapered wedge stem in primary
THA ; however, patients with coexisting diseases could not acquire sufficient improvement in hip function andambulatory ability. J. Med. Invest. 70 : 471-475, August, 2023
Keywords : hip, joint replacement, total hip arthroplasty

INTRODUCTION
Previous studies reported that cementless femoral stems
have excellent results during long-term periods, except for
metal-on-metal total hip arthroplasty (THA) (1-4). Various
types of cementless stems associated with excellent clinical andradiographic outcomes are currently available worldwide (5, 6).
In July 2009, our institute began using a taper wedged cementless femoral stem (Accolade TMZF stem : Stryker Orthopaedics : Mahwah NJ, USA) for THA. Several reports of this stem
documented excellent results during the short to middle-term
period and other papers stated concerning migration with initialinstability, initial rotational instability and distal femoral cortical hypertrophy relating to thigh pain but did not document indetail about complications and unsatisfied results (7-10). Overall, we have good impression of outcome of THA with using thisstem. However, we have several patients with unsatisfactory result and feeling although we have succeeded THA procedure andhave found no abnormal findings in the serial radiographs. We
suspected one of background factors of decreasing clinical hipscore was presence of coexisting diseases at preoperative timeor occurrence of coexisting diseases during follow up periods although there was no apparent abnormal findings and symptoms
around hip joint.
The purpose of the current study was to evaluate the results ofprimary THA using a stem with 5- to 12-year follow up. We also
investigated complications and the background of poor resultswith relationship of coexisting diseases and walking as well as
Received for publication March 13, 2023 ; accepted July 24, 2023.
Address correspondence and reprint requests to Yuto Sugimine,
Department of Orthopedics, Tokushima Municipal Hospital, 2-34 KitaJosanjima, Tokushima 770-0812, Japan and Fax : +81-88-622-9379.
E-mail : yuto.s8906@gmail.com

activities of daily living (ADL) function.

MATERIAL AND METHODSWe retrospectively evaluated the clinical and radiographic
results at pre-operation, after 3-month, 6-month postoperatively
and annual follow-up. Between 2009 and 2014, 273 consecutive primary cementless THAs using contemporary titanium
tapered wedge cementless femoral stem were performed in 242
patients by the same senior surgeon in our hospital and wereretrospectively followed up. Ten patients died (mean follow-up
period, 27.0 months) regardless of the operation within 5 years
postoperatively. They underwent no revision surgery and had noevidence of radiological failure. A total of 43 patients (mean follow-up period, 33.7 months) were lost to follow-up within 5 years,of whom 33 declined to attend for review and the remaining 10
patients had no contact with us by telephone. The mean age ofthe remaining 187 patients with 213hips was 65 years (20–89
years) at the time of the operation, with 167 female and 20 males.
There were 181 osteoarthritic hips, 14 idiopathic osteonecrosis of
the femoral head, 7 rapidly destructive coxarthrosis, 5 osteoarthritis after osteotomy, 5 rheumatoid arthritis, and 1 post-traumatic osteoarthritis. All operations were performed in a verticallaminar flow theater with an aspiration head cover.
The direct lateral approach described by Hardinge (11) wasused in all patients. We used the Accolade TMZF stem, which
consisted of a beta titanium tapered wedge alloy stem with a
PureFix HA coating proximally. We excluded cases with severe
deformity or highly dislocation hip, which required peritrochanteric osteotomy and other types of femoral prosthesis. We useda Trident cup (Stryker Orthopaedics : Mahwah NJ, USA) for
121 hips and a Tritanium cup (Stryker Orthopaedics : Mahwah
NJ, USA) for 92 hips. The cup was press-fit after 1 mm undersize reaming, and supplemental screws were used as needed.

The Journal of Medical Investigation Vol. 70 2023

Y. Sugimine, et al. Clinical outcome of tapered wedge stem

472

Concerning the articular surface, cross-linked polyethylene on
the ceramic interface was used in all but seven cases with ceramic-on-ceramic interface.
Clinical outcomes were assessed according to the Japanese
Orthopaedics Association (JOA) scoring system (12), which consist of pain (40 points), mobility (20 points), gait (20 points), andactivities of daily living (20 points). The results were categorized
as excellent (95-100 points), good (85-94 points), fair (75-84
points), or poor (< 75 points). Owing to investigate how coexisting
cerebral, spinal, musculoskeletal diseases disturbed the improvement of hip function and ambulance ability after THA andleaded to unsatisfactory results and feelings, we classified twogroups to compared clinical outcomes, that is, 89 hips with coexisting cerebral, spinal, musculoskeletal diseases and 124 hipswith no coexisting diseases. We defined coexisting diseases as
diseases disturb the improvement of hip function and ambulanceability except hip diseases. Coexisting disease and concerning
about necessity of walking aids investigated at the latest follow
up time. The onset of these coexisting disease doesn’t matter.
We investigated complications occurring perioperative or
during the follow-up period, especially periprosthetic fracture,
nerve injury, dislocation, and infection.
Radiological outcomes were assessed using serial plain hip
A-P view radiography according to a Gruen zoning system(13). Preoperative radiographs were evaluated the shape of theproximal femoral canal (14), and immediate postoperative radiographs were evaluated for stem positioning (neutral, varus,
valgus) (15). Follow-up radiographs were assessed ectopic ossification (16) and host bone response such as spot welds, cortical
hypertrophy, stress shielding (17) and subsidence.
The intraobserver and interobserver reliabilities of radiographic evaluation were assessed in 30 randomly selectedpatients. All measurements were performed twice by two independent observers who were blinded to the results reported by
the other observers. The intraobserver and interobserver reliability were measured on the basis of the intraclass correlationalcoefficient (ICC) for stem alignment and kappa coefficient forother parameters. Statistically significant differences between
coexisting diseases and no coexisting diseases groups were
examined using the unpaired Student’s t-test. Statistical significance was set at p < 0.05.
The study had ethical approval and all patients gave informed
consent.

RESULTS
One hundred and eighty-seven patients (77.3%) were followed
up for more than 5 years postoperatively.
Clinical evaluation was available in 187 patients with 213 hips
at a mean of 102 months (range, 60–150 months). The mean JOA
score improved from 49 (range, 21-75) to 92 (range, 59-100) at themost recent follow up, which did not have a subsequent revision
for changing the stem implant. The result at the latest follow up
was excellent in 121 hips, good in 46 hips, fair in 34 hips, andpoor in 12 hips (11 patients). The all 11 patients had symptoms
related to cerebral, spinal, and musculoskeletal disorders whichwere unrelated to THA surgery. Eight patients received revision
surgery. Some patients with the poor results tended to sufferfrom pain and muscular weakness of lower extremities. In somecases, cerebral, spinal, musculoskeletal diseases led discomfort
around the hip joint or gait disturbance as well as reduction inlocomotive function in daily life. As shown in Table 1, the coexisting disease group was significantly older at the operative age
and at the latest follow-up age and significantly lower pre JOA
score (especially gait score and ADL score) at final follow-up than
the no coexisting disease group. At the latest follow up time inthis current study, 154 hips (mean age of 69.8 years) were able
to walk without aids and 59 hips (mean age of 80.3 years) used
one or two canes or wheel walker. Complications occurred in 23
hips (Table 2). Intraoperative fracture occurred in 12 hips, which
consisted of 4 femoral shaft fractures and 8 greater trochantericfractures. None of the femoral shaft fracture cases had sinkingof the stem implant. One of the greater trochanteric fracture
cases had no fusion. Sciatic nerve palsy presented immediately
after the operation in two patients. One patient showed complete
improvement within 6 months, but the other had a few weaknesses in dorsiflexion of the ankle and toes. Superficial infection

Table 2. Post-operative complications
Complication

Number (%)

Intra-operative fracture

12 (4.8)

Recurrent dislocation

3 (1.2)

Infection

1 (0.4)

Sciatic nerve palsy

2 (0.8)

Acetabular cup loosening

6 (2.4)Total

24 (9.6)

Table 1. significant difference between coexisting disease group and no coexisting disease group
Hips number

Total

coexisting disease

no coexisting disease

213

91

122

Mean age years at the operation (range)*64.2 (20 to 89)

70.3 (20 to 89)

60.0 (29 to 89)

Mean age years at latest follow-up (range)*

72.7 (32 to 95)

78.5 (32 to 95)

68.3 (36 to 89)

Pre-operative JOA score*(S.D.)

49.3

46.4 (10.8)

51.7 (11.8)

Gait score*(S.D.)

9.0

7.5 (3.9)

10.2 (4.0)

ADL score*(S.D.)

13,0

12.1 (2.6)

13.4 (2.8)

Latest follow-up JOA score*(S.D.)

91.8

83.8 (9.60)

97.7 (3.41)

Gait score*(S.D.)

15.8

10.8 (6.25)

19.6 (1.32)

ADL score*(S.D.)

17.8

15.0 (3.38)

19.9 (9.26)*t-test p < 0.01

The Journal of Medical Investigation Vol. 70 August 2023
occurred in one patient at one week postoperatively. Threepatients had a dislocation at 4 months, 2 and 8 years postoperatively. In the first case, the anteversion of the acetabular metal
cup was decreased, an elevated liner was used, and the diameterof the ceramic head was increased from 28 mm to 32 mm. In
the second and third cases, the dual-mobility system and necklength were increased to 8 mm. None of the cases required stemchange due to malposition of the stem. No further dislocations
were observed.
We experienced 6 hips with aseptic cup loosening consistingof one Trident cup and five Tritanium cup cases. One patientwith the Trident cup was not able to acquire good initial fixation
owing to poor bone quality due to rapidly destructive coxarthritis. She underwent revision surgery with Trabecular metal cup(Zimmer Biomet : Kalamazoo MI, USA) filled with allograft or
trabecular metal augmentation 5 years after primary surgery.
Four patients with the Tritanium cup converted to a trabecular
cup with allograft or trabecular metal augment at 3, 7, 7.5 and 9
years postoperatively. The remaining one patient was refused toundergo revision surgery.
Radiographs were available for evaluation in 213 hips at amean follow-up of 101 (60–148) months. The shape of proximal
femoral canal was classified as 154 hips normal type, 34 champagne-flute type and 25 stovepipe type. The stems in neutralalignment were 182 hips, valgus alignment were 31 hips (normal : champagne-flute : stovepipe type canal ; 23 : 6 : 2). The
valgus alignments weren’t progress in all cases.

473

Grade I or II heterotopic ossification (16) was observed in 30
hips. Four patients of grade III were not clinically significant.
According to Engh’s criteria (17), all the stems were biologically stable. There was no evidence of progressive osteolysis inproximal or distal around the stem on the radiographs.
In 213 hips, there was no radiolucency around the proximal
HA sleeve portion of the stem. There was stress shielding above
these load-bearing areas, most commonly involving zones 1 and
7 in 144 hips.
A radiolucent line was found around the distal aspect of thestem in 31 hips. Cortical hypertrophy was observed around thestem of 70 hips. This predominantly involved zones 2, 3, 5, and
6. Endosteal spot welds were noted in 208 hips. No hips had beenrevised for femoral loosening at the final follow-up, but one stem
had a 5 mm subsidence within one month postoperatively, andthereafter, no progression was observed (Fig 1).
The intraobserver and interobserver reliability, as measured
on the basis of the ICC and kappa coefficient were shown to beat reliable levels.

DISCUSSION
Tapered wedge cementless femoral components have beenused more than 25 years. Several reports have documented excellent short and middle-term outcomes of Accolade TMZF stem
(7, 8). On the other hand, some papers stated things to focus

Figure 1. 65 y. o. female dislocated hip osteoarthoritisa : Preoperative plain A-P view : The cortex in the left femur was less thin than that in the right femur.
b : Immediate postoperative X-ray showed that the cortical thickness of zone 2 was very thin.
c : One week postoperatively, X-ray showed that the cortical thickness of zone 2 was thinner than that of the immediate postoperative one.
d : One month postoperatively, X-ray showed 5 mm of the stem subsidence and cortical defect of zone 2
e : One year postoperatively, X-ray showed spot welds of zone 6
f : Eleven years postoperatively at final follow-up, X-ray showed cortical hypertrophy of zone 3 and 5. Subsidence did not progress since
one month postoperatively.
Arrow show areas to focus on.

474

Y. Sugimine, et al. Clinical outcome of tapered wedge stemon migration with initial instability and host bone reactions
relating to thigh pain (9, 10). Other studies have documented thecharacteristics of tapered wedge femoral components compared
to different types of stems or femoral geometry (19, 20). Ourcurrent study with 8.5 years (5 years to 12.5 years) follows up
had almost same good result as previous reports (7, 8). Although
we recognized the stem as excellent as previous reports of THA
using the stem (7, 8), we have several patients with the poor
clinical results and experienced several complications in thecurrent study.
Radiographic evaluation showed endosteal spot welds confirmed 93% (207 hips) referred to rigid fixation. Based on radiographic results of periprosthetic bone reaction in the current
study, we confirmed that the stem was a good material for biological fixation.
Elderly people tend to suffer from various diseases and havedecreased locomotive function because of degenerative joint
deformity, lower leg dysfunction, equilibrium disturbance or reduced muscle strength (20, 21). In the current study, 137 patientswith 155 hips (mean age, 69.7 years) were able to walk withoutaids and 50 patients with 58 hips (mean age, 80.6 years) usedcane or wheel walker at the latest follow-up. The mean age at thelatest follow-up was 73 (range, 32-95) years old and 58 patientswith 63 hips (30%) belonged to elderly persons more than 80
years old. We suggest that elderly patients aged > 80 years tend
to have decreased walking ability and respond to walking assist
items. Therefore, we had better consider the importance of walking and ADL function in the JOA score or apply other clinicalscoring systems taking low grade weight concerning walking
and ADL function.
Lamb et al. (22) documented that intra-operative periprosthetic fractures, as a well-known complication of THA, increase
the risk of stem revision and mortality. Several studies havereported that femoral component design and length affect theincidence of intraoperative periprosthetic fractures (18, 23). In
the current study, the majority of complications were intraoperative periprosthetic fractures, of which 12 hips consisted of sevennormal, four valgus positions, and one varus position of the stem.
The femoral canal morphology consisted of three stovepipe type,one champagne-flute type, and eight normal femoral canals.
The abnormal position of the stem and abnormal femoral canalmorphology were important factors leading to fracture, withexcessive eccentric loading around the proximal femoral cortex. I
suggested that we must select the proper shape of the stem with
better adaptation to the morphology of the femoral canal by preoperative planning using 3 dimensional CT (24, 25). As the stem
tended to be inserted in the valgus position for patients with astovepipe canal shape, we might select other stems, that is, distal
fixed-type stems or cemented stems. For prevention of intraoperative fracture, especially in elderly patients with severe osteoporosis, we had better take careful maneuvering of the raspingand stem insertion, and considering the selection of other kindsof stems, especially in cases with stovepipe-type femoral canal.
We performed three revision surgeries for recurrent dislocations. Some papers (8) have documented that initial rotational instability and stem neck anteversion may be affected bydislocation events. Intraoperative findings of the anteversion
angle of the stem were within the correct angle. All cases had
a revised cup component and head but no need for a stem. We
think that all complications did not occur by reason of usage ofthis stem and could be prevented by performing careful surgical
technique.
There are some limitations in this study. First, we had radiographic evaluation using only A-P view.
Radiographs were routinely reviewed using serial A-P viewof the hip for evaluation in our institute ; if necessary, we havelateral view of the operated joint. The accolade stem is a straighttapered single-wedged stem, which is designed to engage metaphyseal cortical bone in one plane, medial to lateral, categorized into type 1 according to Khanuja et al.’s classification (5).
Therefore, we think that the evaluation using A-P radiography
is more useful than lateral radiography and that it is enough toevaluate the stability and fixation of the stem. Second, we used
two kinds of acetabular cups, that is, Trident cup and Tritaniumcup. According to a previous report, the latter cup had a significantly higher rate of radiolucent line occurrence around the cup
than the former cup (26). Other papers (27-29) have documented
revision surgery for aseptic loosening of the Tritanium cup.
Although cup components were not documented in this study
in detail, aseptic cup loosening occurred in five Tritanium cups.
Therefore, the type of cup component may have any influenceon clinical outcomes. Third, almost one third of patients of ourcurrent study were more than 80 years old at the latest follow-up.
Because of many coexisting diseases or diseases and poorly daily
activity, they could not visit our hospital’s annual follow-up day.
Therefore, it may be difficult to estimate the clinical outcomesof primary THA using this stem correctly during a long-term
period (more than 10 years).
This study has some limitations. First, the definition of coexisting disease is ambiguous. We defined coexisting diseases
as diseases disturb the improvement of hip function and ambulance ability except hip diseases. However, this is subjective andnot considered how much the diseases influence hip function
or ambulance. Second, the onset of coexisting diseases are notinvestigated because it is cross-sectional study. We investigatedexistence of coexisting diseases at the final follow-up only.
In conclusion, we have shown good clinical outcomes of primary THA using a contemporary tapered wedge titanium femoral
component, which was performed by a senior hip surgeon. We
have an almost good impression of the stem, which provided reliable osteointegration that was durable at a mean of 8.5 years offollow-up. However, we experienced several complications associated with this stem and several patients who felt unsatisfying
results with successful THA procedure at the latest follow up
time. After THA, elderly patients with cerebral, spinal, and musculoskeletal disorders could not acquire sufficient improvementin ambulatory ability and locomotive function.

CONFLICT OF INTERESTS
All authors declare that they have no conflicts of interest.

ACKNOWLEDGEMENTS
This study received no specific grant from and funding agency
in the public, commercial, or not-for-profit sectors.

REFERENCES
1.

2.

3.

Streit MR, Innmann MM, Merle C, Bruckner T, Aldinger
PR, Gotterbarm T : Long-term (20- to 25-year) resultsof an uncemented tapered titanium femoral component
and factors affecting survivorship. Clin Orthop Relat Res
471(10) : 3262-9, 2013
McLaughlin JR, Lee KR : Long-term results of uncemented
total hip arthroplasty with the Taperloc femoral component
in patients with Dorr type C proximal femoral morphology.
Bone Joint J 98-B(5) : 595-600, 2016
Marshall AD, Mokris JG, Reitman RD, Dandar A,

The Journal of Medical Investigation Vol. 70 August 2023
Mauerhan DR : Cementless titanium tapered-wedge
femoral stem : 10- to 15-year follow-up. J Arthroplasty
19(5) : 546-52, 2004
4. Griffiths JT, Roumeliotis L, Elson DW, Borton ZM, Cheung
S, Stranks GJ : Long Term Performance of an Uncemented,
Proximally Hydroxyapatite Coated, Double Tapered, Titanium-Alloy Femoral Stem : Results From 1465 Hips at 10
years Minimum Follow-Up. J Arthroplasty 36(2) : 616-622,
2021
5. Khanuja HS, Vakil JJ, Goddard MS, Mont MA : Cementless femoral fixation in total hip arthroplasty. J Bone Joint
Surg Am 93(5) : 500-9, 2011
6. Yoshitani J, Kabata T, Kajino Y, Takagi T, Ohmori T, Ueno
T, Ueoka K, Tsuchiya H : The effect of flexion alignment in
total hip arthroplasty with a cementless tapered-wedge femoral stem. Eur J Orthop Surg Traumatol 28(8) : 1625-1632,
2018
7. van den Hout JA, Koenraadt KL, Wagenmakers R, Bolder
SB : The Accolade TMZF stem fulfils the demands of modern stem design : Minimum 5-year survival in a cohort of937 patients. J Orthop Surg (Hong Kong) 26(3), 2018
8. Pierce TP, Jauregui JJ, Cherian JJ, Elmallah RD, Robinson
K, Mont MA : Prospective evaluation of short and mid-term
outcomes of total hip arthroplasty using the Accolade™
stem. Hip Int 25(5) : 447-51, 2015
9. Iwamoto Y, Kijima H, Tazawa H, Konishi N, Kubota H,
Yamada S, Tani T, Kamo K, Suzuki N, Okudera Y, Fujii
M, Sasaki K, Kawano T, Nagahata I, Miyakoshi N, Shimada Y : Initial Rotational Instability of the Tapered
Wedge-Shaped Type Cementless Stem. Adv Orthop Sep
22 ; 2020 : 2180260, 2020
10. White CA, Carsen S, Rasuli K, Feibel RJ, Kim PR, Beaulé
PE : High incidence of migration with poor initial fixationof the Accolade stem. Clin Orthop Relat Res 470(2) : 410-7,
2012
11. Hardinge K : The direct lateral approach to the hip. J Bone
Joint Surg (Br) 64-B : 17-19, 1982
12. Kuribayashi M, Takahashi KA, Fujioka M, Ueshima K,
Inoue S, Kubo T : Reliability and validity of the Japanese
Orthopaedic Association hip score. J Orthop Sci 15(4) : 4528, 2010
13. Gruen TA, McNeice GM, Amstutz HC : “Modes of failure”
of cemented stem-type femoral components : a radiographic
analysis of loosening. Clin Orthop Relat Res (141) : 17-27,
1979
14. Noble PC, Alexander JW, Lindahl LJ, Yew DT, Granberry
WM, Tullos HS : The anatomic basis of femoral component
design. Clin Orthop Relat Res (235) : 148-65, 1988
15. Khalily C, Lester DK : Results of a tapered cementless femoral stem implanted in varus. J Arthroplasty 17(4) : 463-6,
2002
16. Brooker AF, Bowerman JW, Robinson RA, Riley Jr LH : Ectopic ossification following total hip replacement. Incidence and a method of classification. J Bone Joint Surg Am
55(8) : 1629-32, 1973
17. Engh CA, Bobyn JD, Glassman AH : Porous-coated hip
replacement. The factors governing bone ingrowth, stressshielding, and clinical results. J Bone Joint Surg Br

475

69(1) : 45-55, 1987
18. Park CW, Eun HJ, Oh SH, Kim HJ, Lim SJ, Park YS : Femoral stem survivorship in Dorr type A femurs after total hip
arthroplasty using a cementless tapered wedge stem : A
matched comparative study with type B fractures. J Arthroplasty 34(3) : 527-533, 201919. Colacchio ND, Robbins CE, Aghazadeh MS, Talmo CT,
Bono JV : Total hip intraoperative femur fracture : Do thedesign enhancements of a second-generation tapered-wedge
stem reduce the incidence? J Arthroplasty 32(10) : 31633168, 2017
20. Khanuja K, Joki J, Bachmann G, Cuccurullo S : Gait andbalance in the aging population : Fall prevention using innovation and technology. Maturitas 110 : 51-56, 2018
21. Austin DC, Torchia MT, Moschetti WE, Jevsevar DS,
Keeney BJ : Patient outcomes after total hip arthroplasty
in extreme elderly patients older than 80 years. Hip Int
30(4) : 407-416, 2020
22. Lamb JN, Matharu GS, Redmond A, Judge A, West RM,
Pandit HG : Patient and implant survival following intraoperative periprosthetic femoral fractures during primary
total hip arthroplasty : an analysis from the national joint
registry for England, Wales, Northern Ireland and the Isleof Man. Bone Joint J 101-B(10) : 1199-1208, 201923. Carli AV, Negus JJ, Haddad FS : Periprosthetic femoral
fractures and trying to avoid them : what is the contribution of femoral component design to the increased risk ofperiprosthetic femoral fracture? Bone Joint J 99-B(1 SuppleA) : 50-59, 201724. Inaba Y, Kobayashi N, Oba M, Ike H, Kubota S, Saito
T : Difference in postoperative periprosthetic bone mineraldensity changes between 3 major designs of uncemented
stem : a 3-year follow-up study. J Arthroplasty 31(8) : 183641, 2016
25. Oba M, Inaba Y, Kobayashi N, Ike H, Tezuka T, Saito T : Effect of femoral canal shaped on mechanical stress distribution and adaptive bone remodelling around a cementlesstapered-wedge stem. Bone Joint Res 5(9) : 362-9, 2016
26. Yoshioka S, Nakano S, Kinoshita Y, Nakamura M, Goto
T, Hamada D, Sairyo K : Comparison of a highly porous
titanium cup (Tritanium) and a conventional hydroxyapatite-coated porous titanium cup : A retrospective analysisof clinical and radiological outcomes in hip arthroplasty
among Japanese patients. J Orthop Sci 23(6) : 967-972, 2018
27. Long WJ, Nayyar S, Chen KK, Novikov D, Davidovitch RI,
Vigdorchik JM : Early aseptic loosening of the Tritanium
primary acetabular component with screw fixation. Arthroplasty Today 2 ; 4(2) : 169-174, 201828. Palomäki A, Hemmilä M, Laaksonen I, Matilainen M,
Eskelinen A, Haapakoski J, Puhto AP, Kettunen J, Manninen
M, Mäkelä KT : Implant Survival of 6,080 Tritanium Cups
in Primary Total Hip Arthroplasty : Data from the Finnish
Arthroplasty Register from 2009 to 2017. J Bone Joint Surg
Am 1 ; 102(13) : 1177-1185, 2020
29. Carli AV, Warth LC, de Mesy Bentley KL, Nestor BJ : Shortto midterm follow-up of the Tritanium primary acetabular
component : A cause for concern. J Arthroplasty 32(2) : 463469, 2017