228 / 324
the light of recent work the ‘anteromedial with
medial patellar facet’ group was also included
as being a candidate for RUKA, however the
‘anteromedial with lateral patellar facet’ group
was not [25, 26].
Self-assessed functional outcome
Twenty sequential TKAs were compared with
20 age- and sex-matched medial UKAs, 20
age- and sex-matched lateral UKAs and 20
age- and sex-matched disease-free controls
(recruited from an upper limb clinic with no
history of lower limb problems). Functional
outcome was quantified using the Total Knee
Questionnaire (TKQ) [27-29] which was desi-
gned specifically to avoid the ceiling effects
found in most knee scores. The relationship
between type of arthroplasty (medial, lateral,
total and control) and knee function was exa-
mined for significance using analysis of varian-
ce (ANOVA) implemented in the statistical
package SPSS version 12.0 (Chicago, Illinois).
The source of between-group differences was
assessed using unpaired t-tests based on an
assumption of equal between-group variances
(validated using Levene’s test).
Financial costs
Surgery
The UK National Joint Registry (NJR) report
from 2007 shows that the most commonly
used TKA is the PFC Sigma Bicondylar Knee
(34.9% of TKA in the UK), the most common-
ly used UKA is the Oxford phase III (73% of
UKA in the UK) and the most commonly used
ROBOT ASSISTED UNICONDYLAR KNEE ARTHROPLASTY IS COST-EFFECTIVE
227
Pattern
Definition
Anteromedial (AM)
Ahlback 1 or worse changes isolated to the medial compartment,
anterior to the mid saggital plane on the lateral radiograph
Medial (M)
Ahlback 1 or worse changes isolated to the medial compartment,
extending posterior to the mid saggital plane on the lateral radiograph
Lateral (L)
Ahlback 1 or worse changes isolated to the lateral compartment
Medial PFJ (MP)
Ahlback 1 or worse changes isolated to the patello-femoral joint
medial compartment
Lateral PFJ (LP)
Ahlback 1 or worse changes isolated to the patello-femoral joint
medial compartment
Tricompartmental (T)
Ahlback 1 or worse changes in all 3 conpartments
Bicompartmental (B)
Ahlback 1 or worse changes in both tibio-femoral compartments
Anteromedial with medial A combination of both anteromedial and medial PFJ patterns
PFJ (AMP)
Anteromedial with lateral
A combination of both anteromedial and lateral PFJ patterns
PFJ (ALP)
Medial with medial
A combination of both medial and medial PFJ patterns
PFJ (MMP)
Medial with lateral
A combination of both medial and lateral PFJ patterns
PFJ (MLP)
Other (O)
Not otherwise classifiable (post-traumatic, post menisectomy, etc)
Table 1 : Patterns of knee arthritis