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                                                                   EXHIBIT 10.34


                        AMENDMENT TO SEVERANCE AGREEMENT

     THIS AMENDMENT TO SEVERANCE AGREEMENT (this "Amendment") is made this 31st
day of December, 1998, by and between ENCORE ORTHOPEDICS, INC., a Delaware
corporation, with its principal office located at 9800 Metric Blvd., Austin,
Texas 78758 (the "Company") and KATHY WIEDERKEHR, an individual resident at
11501 Cherry Hearst, Austin, Texas 78750  (the "Employee").

     WHEREAS, the Employee and the Company entered into a Severance Agreement
dated April 1, 1997 (the "Agreement") which provided, inter alia, for certain
payments to be made in the event that certain events occurred with respect to
the Employee's employment relationship with the Company;

     WHEREAS, the Employee and the Company desire that there be certain changes
made with respect to the Agreement; and

     WHEREAS, the Company and the Employee want to memorialize in this Amendment
their agreements regarding such changes to the Agreement.

     NOW THEREFORE, in consideration of the premises and other mutual promises
and covenants contained in this Amendment and for other good and valuable
consideration, the receipt and adequacy of which are hereby acknowledged, the
parties, intending legally to be bound, agree as follows:

     1. Section 2(c) of the Agreement shall be deleted and shall have no further
force and effect.

     2. Except as specifically changed by the Amendment, all other terms and
provisions of the Agreement shall remain in full force and effect.

     IN WITNESS WHEREOF, the Company has caused this Amendment to be executed by
its duly authorized officer and the Employee has hereunto set its hand as of the
date and year first written above.


                                       ENCORE:

                                       ENCORE ORTHOPEDICS, INC.


                                       By: /s/ NICK CINDRICH
                                          --------------------------------------
                                          Nick Cindrich, Chief Executive Officer


                                       EMPLOYEE:

                                       /s/ KATHY WIEDERKEHR
                                       -----------------------------------------
                                       KATHY WIEDERKEHR