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                                                                     EXHIBIT 4.5



                            SECURED PROMISSORY NOTE

$24,924.67                                                    New York, New York
                                                                    July 7, 2000


        SECTION 1. GENERAL.

               For value received, Michael R. McBrayer (the "Payor") hereby
promises to pay in cash to the order of DonJoy, L.L.C., a Delaware limited
liability company, or its successors and assigns (the "Payee"), the principal
amount of TWENTY FOUR THOUSAND NINE HUNDRED TWENTY FOUR DOLLARS AND SIXTY SEVEN
CENTS ($24,924.67) or such greater or lesser principal amount which may be
outstanding hereunder (including as a result of the exercise of the PIK Option),
on July 7, 2007 (including any date upon which the Payor actually repays the
obligations hereunder, the "Maturity Date"). All payments hereunder shall be
made in such coin or currency of the United States of America as at the time of
payment shall be legal tender therein for the payment of public and private
debts. The Payor shall pay interest on July 7 of each calendar year (the
"Interest Payment Date"), commencing July 7, 2001, and on the Maturity Date,
payable in cash (unless the Payor elects to exercise the PIK Option in the
manner set forth below), on the unpaid balance of the principal amount of this
Note at the rate of 6.62% from the date hereof through and including the
Maturity Date. Interest hereunder shall accrue on a daily basis, computed on the
basis of a 360-day year and the actual number of days elapsed. Notwithstanding
the foregoing, the Payor shall have the option on any Interest Payment Date to
pay the interest due on such date (the "Scheduled Interest Payment") by electing
(the "PIK Option") to increase the principal amount due under this Note by the
amount of such Scheduled Interest Payment, whereupon, immediately thereafter,
the principal amount of this Note shall be increased by the amount of such
Scheduled Interest Payment and interest thereafter shall accrue on the principal
amount of this Note as so increased. The principal of, and interest on, this
Note shall be payable by wire transfer of immediately available funds to the
account of the Payee or by check payable to the Payee.

        SECTION 2. PREPAYMENT. The Payor may prepay the principal amount due
under this Note in whole or in part at any time without premium or penalty,
provided that such prepayment is accompanied by the payment of interest accrued
through the date of such prepayment.

        SECTION 3. EVENTS OF DEFAULT.

               (a) Definitions. In each case of the happening of the following
events (each of which is an "Event of Default"):

                      (i) if a default occurs in the payment of any premium,
        installment of, principal of, interest on, or other obligation with
        respect to, this Note, whether at the due date thereof or upon
        acceleration thereof, and such default shall continue for more than ten
        (10) days after notice thereof from the Payee;

                      (ii) if the Payor shall (1) apply for or consent to the
        appointment of a receiver, trustee, custodian or liquidator of his
        property, (2) admit in writing his inability

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        to pay his debts as they mature, (3) make a general assignment for the
        benefit of creditors, or (4) file a voluntary petition in bankruptcy, or
        a petition or an answer seeking reorganization or an arrangement with
        creditors, or to take advantage of any bankruptcy, reorganization,
        insolvency, readjustment of debt, dissolution or liquidation laws or
        statutes, or an answer admitting the material allegations of a petition
        filed against him in any proceeding under any such law; or

                      (iii) there shall be filed against the Payor an
        involuntary petition seeking the appointment of a receiver, trustee,
        custodian or liquidator of the Payor or a substantial part of his
        assets, or an involuntary petition under any bankruptcy, reorganization
        or insolvency law of any jurisdiction, whether now or hereafter in
        effect (any of the foregoing petitions being hereinafter referred to as
        an "Involuntary Petition") and such Involuntary Petition shall not have
        been dismissed within sixty (60) days after it was filed;

then, upon each and every such Event of Default and at any time thereafter
during the continuance of such Event of Default, at the election of the Payee,
this Note shall immediately become due and payable, both as to principal and
interest (including any deferred interest and any accrued and unpaid interest),
without presentment, demand, or protest, all of which are hereby expressly
waived, anything contained herein or other evidence of such indebtedness to the
contrary notwithstanding (except in the case of an Event of Default under
paragraphs (ii) or (iii) of this Section 3(a), in which event such indebtedness
shall automatically become due and payable).

               (b) Remedies on Default, Etc. In case any one or more Events of
Default shall occur and be continuing and acceleration of this Note shall have
occurred, the Payee may, inter alia, proceed to protect and enforce its rights
by an action at law, suit in equity or other appropriate proceeding, whether for
the specific performance of any agreement contained in this Note, or for an
injunction against a violation of any of the terms hereof or thereof or in and
of the exercise of any power granted hereby or thereby or by law. No right
conferred upon the Payee hereby shall be exclusive of any other right referred
to herein or now or hereafter available at law, in equity, by statute or
otherwise.

        SECTION 4. ACCELERATION. In each case of the happening of the following
events (each of which is an "Acceleration Event"):

                      (i) the termination of the Payor's employment with the
        Payee or any of its Affiliates either as a result of the Payor's
        Resignation (as such term is defined in the Employment Agreement dated
        as of June 30, 1999 (the "Employment Agreement") between the Payor and
        DJ Orthopedics, LLC) or Termination for Cause (as such term is defined
        in the Employment Agreement); or

                      (ii) the occurrence of any event, or series of events
        pursuant to which Chase DJ Partners, LLC and/or its affiliates shall
        cease to beneficially own and/or control (i) at least 20% of the issued
        and outstanding equity interests of the Payee or (ii) all or
        substantially all of the assets of the Payee or any of its subsidiaries;



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then, upon each such Event of Acceleration and at any time thereafter, at the
election of the Payee, this Note shall immediately become due and payable, both
as to principal and interest (including any deferred interest and any accrued
and unpaid interest), without presentment, demand or protest, all of which are
hereby expressly waived, anything contained herein or other evidence of such
indebtedness to the contrary notwithstanding.

        SECTION 5. DEFENSES. The obligations of the Payor under this Note shall
not be subject to reduction, limitation, impairment, termination, defense,
set-off, counterclaim or recoupment for any reason.

        SECTION 6. REPLACEMENT OF NOTES. Upon receipt by the Payor of evidence
satisfactory to him of the loss, theft, destruction, or mutilation of this Note,
and (in case of loss, theft or destruction) of an indemnity reasonably
satisfactory to him, and upon surrender and cancellation of this Note, if
mutilated, the Payor will deliver a new Note of like tenor in lieu of this Note.
Any Note delivered in accordance with the provisions of this Section 6 shall be
dated as of the date of this Note.

        SECTION 7. EXTENSION OF MATURITY. Should the principal of or interest on
this Note become due and payable on other than a business day, the maturity date
thereof shall be extended to the next succeeding business day, and, in the case
of principal, interest shall be payable thereon at the rate per annum herein
specified during such extension. For the purposes of this Note, a business day
shall be any day that is not a Saturday, Sunday, or legal holiday in the State
of New York.

        SECTION 8. ATTORNEYS' AND COLLECTION FEES. Should the indebtedness
evidenced by this Note or any part hereof be collected at law or in equity or in
bankruptcy, receivership or other court proceedings, or this Note be placed in
the hands of attorneys for collection, the Payor agrees to pay, in addition to
principal and interest due and payable hereon, all costs of collection,
including reasonable attorneys' fees and expenses, incurred by the Payee in
collecting or enforcing this Note.

        SECTION 9. WAIVERS. The Payor hereby waives presentment, demand for
payment, notice of dishonor, notice of protest and all other notices or demands
in connection with the delivery, acceptance, performance or default of this
Note.

               No delay by the Payee in exercising any power or right hereunder
shall operate as a waiver of any power or right, nor shall any single or partial
exercise of any power or right preclude other or further exercise thereof, or
the exercise of any other power or right hereunder or otherwise; and no waiver
whatsoever or modification of the terms hereof shall be valid unless set forth
in writing by the Payee and then only to the extent set forth therein.

        SECTION 10. RECOURSE. The obligations of the Payor under this Note are
secured as set forth in the Second Amended and Restated Pledge Agreement, dated
as of the date hereof, between the Payee and the Payor, a copy of which is
attached hereto and incorporated herein as Exhibit A (the "Pledge Agreement").
The Payee's recourse on a default under this Note will be to first fully
exercise its remedies under the Pledge Agreement with respect to the Pledged
Securities (as such term is defined therein), before the Payor will be liable
for any deficiency



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remaining after such a foreclosure and application of the proceeds.

        SECTION 11. AMENDMENTS AND WAIVERS. No provision of this Note may be
amended or waived without the express written consent of both the Payor and the
Payee.

        SECTION 12. GOVERNING LAW. This Note is made and delivered in, and shall
be governed by and construed in accordance with the laws of, the State of New
York (without giving effect to principles of conflicts of laws).

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               IN WITNESS WHEREOF, the Payor has duly executed and delivered
this Note as of the date first written above.



                                            /s/ MICHAEL R. MCBRAYER
                                            ------------------------------------
                                            Michael R. McBrayer