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                                                                   EXHIBIT 10.21

                   THIS NOTE HAS BEEN ACQUIRED FOR INVESTMENT
                      AND HAS NOT BEEN REGISTERED UNDER THE
                    SECURITIES ACT OF 1933 OR THE SECURITIES
                     LAWS OF ANY STATE. THIS NOTE MAY NOT BE
                   SOLD OR TRANSFERRED IN THE ABSENCE OF SUCH
                      REGISTRATION OR AN OPINION OF COUNSEL
                      SATISFACTORY TO THE ISSUER THAT SUCH
                    REGISTRATION IS NOT REQUIRED BY SAID ACT
                                 OR STATE LAWS,


                                ORTHOMETRIX, INC.


$25,000.00                                                White Plains, New York
                                                          October 8, 2003


         ORTHOMETRIX, INC., a Delaware corporation (the "Company"), for value
received, promises to pay to YUKON ASSOCIATES (the "Payee"), the principal sum
of Twenty Five Thousand U.S. Dollars ($25,000) on October 8, 2004 (the "Maturity
Date"), except as otherwise provided herein, together with interest on the
outstanding principal amount of this Note at the rate of prime (as published
from time to time by JP Morgan Chase) plus one per annum, except as otherwise
provided herein. Interest shall be payable quarterly on the last business day of
each March, June, September and December, commencing December 31, 2003.

         3. Payments and Prepayments.

         1.1 Payments and prepayments of principal and interest on this Note
shall be made to Payee at 31 Yukon Dr., Woodbury, N.Y. 11797.

         1.2 Payments and prepayments of principal and interest on this Note
shall be made in lawful money of the United States of America.

         1.3 If any payment on this Note becomes due and payable on a Saturday,
Sunday or other day an which commercial banks in New York City are authorized or
required by law to close, the maturity thereof shall be extended to the next
succeeding business day, and, with respect to payments of principal, interest
thereon shall be payable during such extension at the then applicable rate.

         1.4 The Company shall be obligated to prepay the outstanding principal
amount of this Note within ten (10) days after such time as (i) the Company
receives the Release Payment due on or before January 31, 2004 from
CooperSurgical, Inc. under the Asset Purchase


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Agreement dated as of February 27, 2002, or (ii) the Company receives net
proceeds of at least $1,000,000 from an equity financing, or (iii) the Company
sells substantially all its assets. The Company shall have the right at any time
and from time to time to prepay this Note in whole or in part, together with
interest on the amount prepaid to the date of prepayment, without penalty or
premium. Upon payment of part of the principal amount of this Note, the Company
may require the holder to present this Note for notation of such payment and, if
this Note is paid in full, require the holder to surrender this Note.

         1.5 Upon payrnent in full of all outstanding principal and interest due
under this Note, the Company's obligations in respect of payment of this Note
shall terminate and the holder shall return it to the Company.

         2. Events of Default. In the event that:

            (e) the Company defaults for more than five business days in making
            any payment required to be made on this Note; or

            (f) the Company hereafter makes an assignment for the benefit of
            creditors, or files a petition in bankruptcy as to itself, is
            adjudicated insolvent or bankrupt, petitions or applies to any
            tribunal for the appointment of any receiver of or any trustee for
            the Company or any substantial part of its property under any
            bankruptcy, reorganization, arrangement, readjustment of debt,
            dissolution or liquidation law or statute of any jurisdiction,
            whether now or hereafter in effect; or if there is hereafter
            commenced against the Company any such proceeding and an order
            approving the petition is entered or such proceeding remains
            undismissed for a period of 60 day, or the Company or its general
            partner by any act or omission to act indicates its consent to or
            approval of or acquiescence in any such proceeding or the
            appointment of any receiver of, or trustee for, the Company or any
            substantial part of its property, or suffers any such receivership
            or trusteeship to continue undischarged for a period of 60 days;

then, and in any such event, and at any time thereafter, if such event shall
then be continuing, the holder of this Note may, by written notice to the
Company, declare the Note due and payable, whereupon the same shall be due and
payable without presentment, demand, protest or other notice of any kind, all of
which are hereby expressly waived.

         3. Investment Representation.

         3.1 The Payee hereby acknowledges that the Note is not being registered
(i) under the Securities Act of 1933, as amended (the "Act"), on the ground that
the issuance of the Note is exempt from registration under Section 4(2) of the
Act as not involving any public offering or (ii) under any applicable state
securities law because the issuance of the Note does not


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involve any public offering; and that the Company's reliance on the Section 4(2)
exemption of the Act and under applicable state securities laws is predicated in
part on the representations hereby made to the Company by the Payee that it is
acquiring the Note for investment for its own account, with no present intention
of dividing its participation with others or reselling or otherwise distributing
the same, subject, nevertheless, to any requirement of law that the disposition
of its property shall at all times be within its control.

         3.2 The Payee hereby agrees that it will not sell or transfer all or
any part of this Note unless and until it shall first have given notice to the
Company describing such sale or transfer and furnished to the Company an
opinion, reasonably satisfactory to counsel for the Company, of counsel skilled
in securities matters (selected by the holder and reasonably satisfactory to the
Company) to the effect that the proposed sale or transfer may be made without
registration under the Act and without registration or qualification under any
state.

         3.3 The Company may refuse to recognize a transfer of this Note on its
books should a holder attempt to transfer this Note otherwise than in compliance
with this Section 3.

         4. Miscellaneous.

         4.1 Upon receipt of evidence reasonably satisfactory to the Company of
the loss, theft, destruction or mutilation of this Note and of a letter of
indemnity reasonably satisfactory to the Company, and upon reimbursement to the
Company of all reasonable expenses incident thereto, and upon surrender or
cancellation of the Note, if mutilated, the Company will make and deliver a new
Note of like tenor in lieu of such lost, stolen, destroyed or mutilated Note.

         4.2 This Note and the rights and obligations of the Company and each
holder hereunder shall be construed in accordance with and be governed by the
laws of the State of New York.

         IN WITNESS WHEREOF, the Company has executed this Note as of the day
and year first above written.

                                              ORTHOMETRIX, INC,



                                              By: /s/ Reynald Bonmati
                                                  -----------------------
                                                  Name:  Reynald Bonmati
                                                  Title: President