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                                                                   EXHIBIT 4.7


                       AMENDMENT NO. 1 TO RIGHTS AGREEMENT

                                       OF

                                AROS CORPORATION.


        THIS AMENDMENT NO. 1 TO RIGHTS AGREEMENT (this "Amendment") is entered
into as of this 7th day of June, 2002 by and between Aros Corporation, a
Delaware corporation formerly known as APACHE Medical Systems, Inc. (the
"Company"), and EquiServe Trust Company, N.A., as successor to First Chicago
Trust Company of New York (the "Rights Agent").

                              W I T N E S S E T H:
                              - - - - - - - - - -

        WHEREAS, the Company and the Rights Agent entered into a Rights
Agreement dated as of May 6, 1997 relating to certain rights in connection with
the Company's stock (the "Rights Agreement"); and

        WHEREAS, the Company is contemplating entering into a merger transaction
with ReGen Biologics, Inc., a Delaware corporation ("ReGen"), pursuant to which
a wholly-owned subsidiary of the Company would merge with and into ReGen, with
ReGen as the surviving corporation (the "Proposed ReGen Merger"); and

        WHEREAS, prior to any Person becoming an "Acquiring Person" under the
Rights Agreement, the Rights Agreement may be amended as the Board of Directors
of the Company may, from time to time, deem necessary or desirable without the
consent of the holders of Rights thereunder; and

        WHEREAS, the Board of Directors of the Company deems it to be in the
best interests of the Company and its stockholders to amend certain provisions
of the Rights Agreement to exclude the Proposed ReGen Merger as specifically set
forth herein.

        NOW THEREFORE, in consideration of the foregoing premises and the mutual
agreements herein contained, the Company and the Rights Agent do hereby agree as
follows:

        1. Section 1(a) of the Rights Agreement is hereby amended and restated
in its entirety as follows:

    "(a) "Acquiring Person" shall mean any Person who or which, together
    with all Affiliates and Associates of such Person, shall be the
    Beneficial Owner (as such terms are hereinafter defined) of 15% or more
    of the Common Shares of the Company then outstanding, but shall not
    include the Company, any Subsidiary of the Company, any employee benefit
    plan of the Company or any Subsidiary of the Company, any entity holding
    Common Shares for or pursuant to the terms of any



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    such plan. Notwithstanding the foregoing, no Person shall become an
    "Acquiring Person" as the result of an acquisition of Common Shares by the
    Company which, by reducing the number of shares outstanding, increases the
    proportionate number of shares beneficially owned by such Person to 15% or
    more of the Common Shares of the Company then outstanding; provided,
    however, that if a Person shall become the Beneficial Owner of 15% or more
    of the Common Shares of the Company then outstanding by reason of share
    purchases by the Company and shall, after such share purchases by the
    Company, become the Beneficial Owner of any additional Common Shares of the
    Company, then such Person shall be deemed to be an "Acquiring Person."
    Notwithstanding the foregoing, if the Board of Directors of the Company
    determines in good faith that a Person who would otherwise be an "Acquiring
    Person," as defined pursuant to the foregoing provisions of this paragraph
    (a), has become such inadvertently, and such Person divests as promptly as
    practicable a sufficient number of Common Shares so that such Person would
    no longer be an "Acquiring Person", as defined pursuant to the foregoing
    provisions of this paragraph (a), then such Person shall not be deemed to be
    an "Acquiring Person" for any purposes of this Agreement. Notwithstanding
    any of the foregoing, neither ReGen Biologics, Inc, a Delaware corporation
    ("ReGen"), nor any Person who as of the date hereof is a stockholder,
    director or officer of ReGen or any of their respective Affiliates or
    Associates, nor Sanderling Venture Partners, nor any of its stockholders,
    directors, officers or other Affiliates or Associates, nor any one or more
    of the foregoing acting together as a group, shall be deemed an "Acquiring
    Person" as a result of a merger of Aros Acquisition Corp., a Delaware
    corporation and wholly-owned subsidiary of the Company ("Acquisition Corp.")
    with and into ReGen (the "Proposed ReGen Merger"), nor the execution,
    delivery or performance of any Merger Agreement by and between the Company,
    Acquisition Corp. and ReGen (the "Proposed ReGen Merger Agreement"),
    pursuant to which the Proposed ReGen Merger may be consummated, nor the
    consummation of any of the transactions contemplated thereby, nor the
    execution, delivery or performance of any document contemplated by the
    Proposed ReGen Merger Agreement, including without limitation the
    Stockholders' Agreement and Proxy, nor the consummation of any of the
    transactions contemplated thereby."

        2. Section 2 of the Rights Agreement is hereby amended by inserting at
the end thereof the following sentence:

    "Upon ten (10) days' prior written notice to the Rights Agent, the
    Rights Agent shall have no duty to supervise, and shall in no event be
    liable for the acts or omissions of, any such co-Rights Agent."

        3. Section 18 of the Rights Agreement is hereby amended by deleting the
word "negligence" where it appears in the second sentence thereof and inserting
in lieu thereof the words "gross negligence".

        4. Section 20(c) of the Rights Agreement is hereby amended by deleting
the word "negligence" and inserting in lieu thereof the words "gross
negligence".



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        5. Section 25(a) of the Rights Agreement is hereby amended and restated
in its entirety as follows:

    "(a) In case the Company shall propose, other than in connection with the
    Proposed ReGen Merger and other transactions contemplated by the Proposed
    ReGen Merger Agreement, (i) to pay any dividend payable in stock of any
    class to the holders of its Preferred Shares or to make any other
    distribution to the holders of its Preferred Shares (other than a regular
    quarterly cash dividend), (ii) to offer to the holders of its Preferred
    Shares rights or warrants to subscribe for or to purchase any additional
    Preferred Shares or shares of stock of any class or any other securities,
    rights or options, (iii) to effect any reclassification of its Preferred
    Shares (other than a reclassification involving only the subdivision of
    outstanding Preferred Shares), (iv) to effect any consolidation or merger
    into or with, or to effect any sale or other transfer (or to permit one or
    more of its Subsidiaries to effect any sale or other transfer), in one or
    more transactions, of 50% or more of the assets or earning power of the
    Company and its Subsidiaries (taken as a whole) to, any other Person, (v) to
    effect the liquidation, dissolution or winding up of the Company, or (vi) to
    declare or pay any dividend on the Common Shares payable in Common Shares or
    to effect a subdivision, combination or consolidation of the Common Shares
    (by reclassification or otherwise than by payment of dividends in Common
    Shares), then, in each such case, the Company shall give to each holder of a
    Right Certificate, in accordance with Section 26 hereof, a notice of such
    proposed action, which shall specify the record date for the purposes of
    such stock dividend, or distribution of rights or warrants, or the date on
    which such reclassification, consolidation, merger, sale, transfer,
    liquidation, dissolution, or winding up is to take place and the date of
    participation therein by the holders of the Common Shares and/or Preferred
    Shares, if any such date is to be fixed, and such notice shall be so given
    in the case of any action covered by clause (i) or (ii) above at least 10
    days prior to the record date for determining holders of the Preferred
    Shares for purposes of such action, and in the case of any such other
    action, at least 10 days prior to the date of the taking of such proposed
    action or the date of participation therein by the holders of the Common
    Shares and/or Preferred Shares, whichever shall be the earlier."

        6. Other than as set forth herein, the Rights Agreement shall continue
in full force and effect.

        7. This Amendment shall become effective immediately prior to the
execution and delivery by all of the parties thereto of the Proposed ReGen
Merger Agreement. If the Proposed ReGen Merger Agreement is not executed and
delivered by all of the parties thereto within five (5) days after the date
hereof, this Amendment shall be void and of no force or effect.

        8. This Amendment shall be deemed to be a contract made under the laws
of the State of Delaware and for all purposes shall be governed by and construed
in accordance with the laws of such State applicable to contracts to be made and
performed entirely within such State.




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        9. This Amendment may be executed in any number of counterparts and each
of such counterparts shall for all purposes be deemed to be an original, and all
such counterparts shall together constitute but one and the same instrument.



              (The Remainder of this Page Intentionally Left Blank)

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        IN WITNESS WHEREOF, the Company and the Rights Agent have executed this
Amendment No. 1 to the Rights Agreement as of the date hereof.



                                    AROS CORPORATION





                                    By: /s/ William R. Lewis
                                       --------------------------------------
                                        Name: William R. Lewis
                                        Title:  Special Committee Member


                                    By: /s/ Alan W. Baldwin
                                       --------------------------------------
                                        Name: Alan W. Baldwin
                                        Title:  Special Committee Member



                                    EQUISERVE TRUST COMPANY, N.A.



                                    By:   /s/ Collin Ekeogu
                                       --------------------------------------
                                        Name: Collin Ekeogu
                                        Title: Director









             (Signature Page to Amendment No. 1 to Rights Agreement)