hta_ knee intro.qxp - Ministero della Salute

9. Discussion
The present report was designed to assess whether the prostheses for TKR currently used in
the Italian clinical practice are supported by evidence, and if implant performance can be correlated
to implant price. We addressed these issues first by performing a context-specific analysis (to
identify which knee systems are currently in use and their prices), a systematic review of the evidence
from formal studies and an analysis of implant performance from the arthroplasty registers
(to identify performance by knee system). Finally with the cost and the effectiveness data so far
assembled, we carried out an economic evaluation to help decision making by the Italian MLHSP.
The context-specific analysis was necessary since the central inventory of medical devices was
not yet operative at the start of the study (and is not completed yet at the time of writing). The
survey allowed us to identify a list of knee systems that are probably representative of all the devices
used in Italy, together with their mean purchasing prices. These prices can be assumed as
“real prices”, i.e. the true amount that purchasers have to pay in the transaction. “Real price” is
sometimes different from the price reported in the manufacturer’s list price as, to our knowledge,
bulk purchase discounts are common.
Manufactures of knee prostheses were involved in our HTA project as stakeholders. We contacted
several companies with a formal letter sent to the main association of manufacturers of
medical technology in Italy (ASSOBIOMEDICA) but elicited scarce interest from manufacturers.
Only 6 companies collaborated with us: BIOMET, DEPUY, LIMA, LINK, MEDACTA, and STRYKER out
of the 25 or more which to our knowledge are active in Italy. No reply or reasons for non-response
were received by the others.
We attempted to identify and synthesise evidence of performance (expressed as survival rate
or revision rate for each knee system) from published literature. Unfortunately, literature in this
field seems to be too generic for our particular research questions. Very few studies met our inclusion
criteria and those that did were poorly reported. For this reason we decided to give more
weight to performance estimates contained in the periodic reports of the arthroplasty registers.
We were forced to refer to national registers of foreign countries, as Italy does not yet have a
national knee prostheses register. At present a National hip arthroplasty register project is running
and will start collecting data in the next months. In the near future, there is the intention to extend
the same protocol to the knee arthroplasty registration. However, we used regional Italian data
thanks to the collaboration and data-sharing spirit of the RIPO (regional register of Emilia-
Romagna).
We noted high variation among the periodic reports published and decided to conduct an enquiry
among the “key-persons” (e.g. the register’s coordinator) of the arthroplasty registers to obtain
collaboration in our project by data-sharing. Unfortunately, few collaborated. Some key persons
reported that the data we asked for were not available for “third party” analysis, sometimes the
data were not available at all as they were not collected on a regular basis. However we greatly
benefited from the collaboration with the AOAJRR (the Australian register) and the RIPO. Their key
persons sent all data we requested rapidly, sometimes performing ad hoc queries and handling.
59