Biomedical Engineering Reference
In-Depth Information
transfer all stresses to the bone-cement interface, leading to
excessive loosening. Also, the spheroid design led to reliance on
ligaments without certainty of maintaining the ankle axis.
Conversely, the 3-part design offers both alignment and stability
without over constraint. They preserve both the axis of the ankle
cylindrical motion and remain as anatomical as possible [47].
The four studies are summarized in Table 4.4 as follows:
Table 4.4
Clinical Data S.T.A.R. Total Ankle Replacement
Study
Valderrabano
(42)
Schernburg
(43)
Kofoed (44)
Kofoed (45)
Device
S.T.A.R.
Mobile Bearing
TAR
S.T.A.R.
Mobile Bearing
TAR
S.T.A.R.
Mobile Bearing
S.T.A.R.
Mobile Bearing
TAR
TAR
Number of cases
68 (65 Patients)
131
Cemented =33
Cementless = 25
Total 58
76
M/F
Male = 31 (48%)
Female =34
(52%)
Male Cemented = 14
Female Cemented = 19
Male Cementless = 16
Female Cementless= 9
Male = 35 (46%)
Female =41(54%)
Age (mean)
56
-
Cemented = 60
Cementless = 58
56
Diagnosis
PTA=48 (71%)
RA = 11(16%)
OA = 9 (13%)
OA, RA
Cemented RA = 13
Cemented OA = 20
Cementless RA = 3
Cementless OA = 22
OA = 44 (58%)
RA = 22(29%)
PA=4(6%)
AVN=4(6%)
Failed Fusion = 1(1%)
Follow-up
Mean 3.7 Year
(2.4-6.2 years)
6yrs
Cemented = 9.3 ± 2.7
Cementless = 9.5 ± 1.7
10 yrs
Delayed Wound
Healing
-
-
-
-
Talar Subsidence
1 (4%)
-
-
-
Bearing subluxation
1 (4%)
-
-
-
Severe bearing wear
3 (13%)
-
Cementless 1(2%)
-
Malleolar fracture
0 (0%)
-
-
-
-
-
-
Infection
0 (0%)
Reflex sympathic
Dystrophy
1 (6%)
-
Cemented 1(2%)
-
Tibial component
loosening
2 (9%)
-
Cemented 6(10%)
-
Cementless 1(2%)
87.3
70 Cemented
86.7
Survivorship (%)
87 (After
component
related revision)
at 6 yrs
(Kofoed, 1986)
95 Cementless
(Kofoed, 1986)
At 6 yrs
(Revision/Removal for
any reason) at 9 yrs
(Revision for any
reason) at 10 yrs
Average Clinical
Score Overall
(Percentage)
85
85
Cemented = 74.2 ± 19.3
Cementless = 91.9 ± 7.4
-
(AOFAS)
(Kofoed, 1986)
