Het volume van chirurgische ingrepen en de impact ervan op ... - KCE
Het volume van chirurgische ingrepen en de impact ervan op ... - KCE
Het volume van chirurgische ingrepen en de impact ervan op ... - KCE
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<strong>KCE</strong> Reports 113 Volume Outcome 187<br />
7.2 ELECTIVE TOTAL KNEE REPLACEMENT/ARTHROPLASTY<br />
(TKR)<br />
7.2.1 G<strong>en</strong>eral <strong>de</strong>scription of procedure<br />
Total knee replacem<strong>en</strong>t or arthr<strong>op</strong>lasty is a procedure in which damaged or diseased<br />
parts of the knee joint are removed and replaced with an artificial joint, called<br />
prosthesis. The thigh bone (or femur) abuts the large bone of the lower leg (tibia) at the<br />
knee joint. During a total knee replacem<strong>en</strong>t, the <strong>en</strong>d of the thigh bone (femur) is<br />
removed and replaced with a metal shell. The <strong>en</strong>d of the lower leg bone (tibia) is also<br />
removed and replaced with a channelled plastic piece with a metal stem. Dep<strong>en</strong>ding on<br />
the condition of the kneecap, a plastic "button" may also be ad<strong>de</strong>d un<strong>de</strong>r the kneecap<br />
surface.<br />
Revision knee replacem<strong>en</strong>t is performed wh<strong>en</strong> the original primary total knee<br />
replacem<strong>en</strong>t has worn out or loos<strong>en</strong>ed in the bone, or wh<strong>en</strong> the primary TKR fails due<br />
to, for example, recurr<strong>en</strong>t dislocation, infection or fracture.<br />
This report only studies the <strong>volume</strong>-outcome relationship for the primary total knee<br />
replacem<strong>en</strong>t.<br />
7.2.2 Primary data selection in MCD 2004<br />
First selection of data was based on ICD-9-CM procedure and NIHDI procedure co<strong>de</strong>s<br />
as pr<strong>op</strong>osed by Taylor et al., and by Jacques et al. This selection resulted in a total of<br />
246, 309<br />
14 105 stays.<br />
Table 7.19: Total knee arthr<strong>op</strong>lasty: Primary data selection in MCD 2004<br />
SELECTION 1 SELECTION 2<br />
ICD-9-CM procedure co<strong>de</strong> NIHDI procedure co<strong>de</strong><br />
8154 TOTAL KNEE REPLACEMENT<br />
8155 REVISE KNEE REPLACEMENT<br />
290264 Femoro-tibial arthr<strong>op</strong>lasty with simple prosthesis<br />
290286 Femoro-tibial arthr<strong>op</strong>lasty with articulated prosthesis<br />
293462 Removal of a total knee prosthesis and placem<strong>en</strong>t of a<br />
new total prosthesis<br />
STAYS SELECTED =13 856 STAYS SELECTED =13 762<br />
7.2.3 Definition of procedure<br />
TOTAL STAYS SELECTED= 14 105<br />
(selection 1 OR selection 2)<br />
Table 7.20 shows that both ICD-9-CM and NIHDI procedures co<strong>de</strong>s were recor<strong>de</strong>d for<br />
almost 96% of the stays. There was thus a good correspond<strong>en</strong>ce betwe<strong>en</strong> both<br />
classification systems.<br />
Table 7.20: Total knee arthr<strong>op</strong>lasty: Cross table ICD-9 and NIHDI<br />
procedures co<strong>de</strong>s<br />
Cumulative Cumulative<br />
Number Perc<strong>en</strong>t Freq Perc<strong>en</strong>t<br />
ICD-9 only 343 2.43 343 2.43<br />
NIHDI only 249 1.77 592 4.20<br />
Both 13 513 95.80 14 105 100.00<br />
Among the 13 513 stays with both an ICD-9 and a NIHDI co<strong>de</strong>, there were 926 which<br />
related to a revision of the hip arthr<strong>op</strong>lasty. These stays were not withheld.<br />
Subsequ<strong>en</strong>tly, we id<strong>en</strong>tified 12 752 stays with one total knee arthr<strong>op</strong>lasty in which both<br />
the NIHDI procedure co<strong>de</strong> 290286 as well as the ICD-9-CM procedure co<strong>de</strong> 8151<br />
were <strong>en</strong>co<strong>de</strong>d. Stays with more than one TKR billed were th<strong>en</strong> discar<strong>de</strong>d<br />
(number=109) together with 190 stays with abnormalities in the data. After<br />
withdrawing the remaining 84 stays with a simple prosthesis (NIHDI co<strong>de</strong> 290264), in<br />
or<strong>de</strong>r to obtain a homog<strong>en</strong>eous p<strong>op</strong>ulation, 12 369 stays could be further examined.