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                                                                     EXHIBIT 4.1

                         INTERPORE INTERNATIONAL, INC.

                         REGISTRATION RIGHTS AGREEMENT

     This Registration Rights Agreement (the "Agreement") is made as of July 10,
                                              ---------
2001, between Interpore International, Inc., a Delaware corporation (the
"Parent") and Eric Major, as agent (the "Target Shareholder Representative") of
 ------
the former shareholders (the "Shareholders") of American OsteoMedix Corporation,
                              ------------
a Virginia corporation (the "Target") identified on Exhibit A hereto.
                             ------                 ---------

     WHEREAS:

     A.  Pursuant to the terms of the Agreement and Plan of Merger dated as of
even date herewith (the "Merger Agreement"), by and among Parent, Target, and OP
                         ----------------
Sub, Inc., a California corporation and wholly owned subsidiary of Parent
("Merger Sub"), Target is being merged with and into Merger Sub (the "Merger"),
 -----------                                                          ------
with Merger Sub being the surviving corporation.

     B.  In connection with the Merger, the Shareholders shall receive fully
paid and non-assessable shares of common stock of Parent, no par value ("Parent
                                                                         ------
Common Stock").
------------

     C.  The Merger Agreement provides for the execution and delivery of this
Agreement at the closing of the transactions contemplated thereby which grants
the Shareholders certain rights to have their Shares registered under the
Securities Act of 1933, as amended.

     NOW, THEREFORE, in consideration of the premises and the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereby agree as
follows:

                                   SECTION 1

                Restrictions on Transferability of Securities;
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              Compliance with Securities Act; Registration Rights
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         1.1  Certain Definitions.  Unless otherwise indicated, the terms in
              -------------------
this Agreement shall have the same meanings as those terms in the Merger
Agreement. As used in this Agreement, the following terms shall have the
following respective meanings:

     "Commission" shall mean the Securities and Exchange Commission or any other
      ----------
federal agency at the time administering the Securities Act.

     "Common Stock" shall mean Parent Common Stock, no par value.
      ------------

     "Holder" shall mean (i) the Shareholders and (ii) any person holding
      ------
Registrable Securities to whom the rights under this Section 1 have been
                                                     ---------
transferred in accordance with Section 1.8 hereof.
                               -----------

     "Registrable Securities" means the Shares until such time that such
      ----------------------
securities have been (i) effectively registered under the Securities Act and
disposed of pursuant to an effective Registration Statement, or (ii) sold in a
single transaction exempt from the registration and prospectus delivery
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requirements of the Securities Act so that all transfer restrictions and
restrictive legends with respect thereto are removed upon the consummation of
such sale.

     The terms "register," "registered" and "registration" refer to a
                --------    ----------       ------------
registration effected by preparing and filing a registration statement in
compliance with the Securities Act, and the declaration or ordering of the
effectiveness of such registration statement.

     "Registration Expenses" shall mean all expenses, except as otherwise stated
      ---------------------
below, incurred by Parent in complying with Section 1.2 hereof, including,
                                            -----------
without limitation, all registration, qualification and filing fees, including
NASD filing fees, printing expenses (including expenses of printing certificates
for Registrable Securities and of printing preliminary and final prospectuses),
escrow fees, fees and disbursements of counsel for Parent, blue sky fees and
expenses, the expense of any special audits incident to or required by any such
registration.

     "Securities Act" shall mean the Securities Act of 1933, as amended, or any
      --------------
similar federal statute and the rules and regulations of the Commission
thereunder, all as the same shall be in effect at the time.

     "Selling Expenses" shall mean all underwriting discounts, selling
      ----------------
commissions and stock transfer taxes applicable to the securities registered by
the Holders and all reasonable fees and disbursements of counsel for any Holder.

     "Shares" shall mean the shares of Common Stock of Parent, no par value,
      ------
issued to the Shareholders pursuant to the Merger Agreement and any other
securities issued in respect of such securities upon any stock split, stock
dividend, recapitalization, merger, consolidation or similar event.

         1.2  Mandatory Registration.  Parent shall use its reasonable efforts
to prepare and file with the Commission, within 30 calendar days following the
Effective Time (as defined in the Merger Agreement) and in all events within 45
calendar days thereafter, except as a result of delays that are caused by the
actions or inactions of the Holders, a registration statement (the "Registration
                                                                    ------------
Statement") on Form S-3 (or, if Form S-3 is not then available to Parent, on
---------
such form of registration statement as is then available to effect a
registration for resale of the Registrable Securities, subject to the Holder's
consent) covering the resale of the Shares by the Holders. Parent shall use its
commercially reasonable efforts to cause the Registration Statement to be
declared effective as promptly as is reasonably practical after the filing
thereof.

         1.3  Expenses of Registration.  All Registration Expenses incurred in
              ------------------------
connection with all registrations pursuant to Section 1.2 shall be borne by
Parent. Unless otherwise stated, each Holder shall bear its own Selling
Expenses.

         1.4  Registration Procedures.  At its expense Parent will:
              -----------------------

              (a)  Prepare and file with the Commission the Registration
Statement with respect to the Shares and use reasonable efforts to cause such
Registration Statement to become effective as soon as is reasonably practical
after the filing thereof, and to keep the Registration

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Statement effective until the earlier of (i) the sale of all Registrable
Securities has been completed or (ii) one year from the effective date of such
Registration Statement. In the event the Holders are unable to sell under such
Registration Statement for any period or periods as a result of the suspension
of effectiveness of the Registration Statement or other blackout periods, then
such period or periods shall be added to the one year period in clause (ii)
above;

              (b)  Prepare and file with the Commission such amendments
(including post-effective amendments) to such Registration Statement, and such
supplements to the related prospectus, as may be required by the rules,
regulations or instructions applicable to the Securities Act during the
applicable period in accordance with the intended methods of disposition
specified by the Holders of the Registrable Securities covered by such
Registration Statement, and cause the related prospectus as so supplemented to
be filed pursuant to Rule 424 under the Securities Act;

              (c)  Notify the Target Shareholder Representative (as defined in
the Merger Agreement) of any Registrable Securities covered by such Registration
Statement promptly and (if requested) confirm such notice in writing, (i) when a
prospectus or any prospectus supplement or post-effective amendment has been
filed, and, with respect to such Registration Statement or any post-effective
amendment, when the same has become effective, (ii) of any request by the
Commission for amendments or supplements to such Registration Statement or the
related prospectus or for additional information regarding such Holders, (iii)
of the issuance by the Commission of any stop order suspending the effectiveness
of such Registration Statement or the initiation of any proceedings for that
purpose, (iv) of the receipt by the Company of any notification with respect to
the suspension of the qualification or exemption from qualification of any of
the Registrable Securities for sale in any jurisdiction or the initiation or
threatening of any proceeding for such purpose, and (v) of the happening of any
event that requires the making of any changes in such Registration Statement,
prospectus or documents incorporated or deemed to be incorporated therein by
reference so that they will not contain any untrue statement of a material fact
or omit to state any material fact required to be stated therein or necessary to
make the statements therein, in light of the circumstances under which they were
made, not misleading;

              (d)  Use commercially reasonable efforts to obtain the withdrawal
of any order suspending the effectiveness of such Registration Statement, or the
lifting of any suspension of the qualification or exemption from qualification
of any Registrable Securities for sale in any jurisdiction in the United States;

              (e)  Furnish to the Holder of any Registrable Securities covered
by such Registration Statement, each counsel for such Holders and each managing
underwriter, if any, without charge, one conformed copy of such Registration
Statement, as declared effective by the Commission, and of each post-effective
amendment thereto, in each case including financial statements and schedules and
all exhibits and reports incorporated or deemed to be incorporated therein by
reference; and deliver, without charge, such number of copies of the preliminary
prospectus, any amended preliminary prospectus, each final prospectus and any
post-effective amendment or supplement thereto, as such Holder may reasonably
request in order to facilitate the disposition of the Registrable Securities of
such Holder covered by such Registration Statement in conformity with the
requirements of the Securities Act;

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<PAGE>

              (f)  Prior to any public offering of Registrable Securities
covered by such Registration Statement, use commercially reasonable efforts to
register or qualify such Registrable Securities for offer and sale under the
securities or Blue Sky laws of such jurisdictions as the Target Shareholder
Representative shall reasonably request in writing; provided, however, that the
Company shall in no event be required to qualify generally to do business as a
foreign corporation or as a dealer in any jurisdiction where it is not at the
time so qualified or to execute or file a general consent to service of process
in any such jurisdiction where it has not theretofore done so or to take any
action that would subject it to general service of process or taxation in any
such jurisdiction where it is not then subject; and

              (g)  Upon the occurrence of any event contemplated by paragraph
1.4(c)(v) above, prepare a supplement or post-effective amendment to such
Registration Statement or the related prospectus or any document incorporated or
deemed to be incorporated therein by reference and file any other required
document so that, as thereafter delivered to the purchasers of the Registrable
Securities being sold thereunder, such prospectus will not contain an untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading.

         1.5  Reports Under Securities Exchange Act of 1934.  With a view to
making available to the Holders the benefits of Rule 144 promulgated under the
Securities Act, the Company agrees to:

              (a)  make and keep public information available, as those terms
are understood and defined in SEC Rule 144, for the two year period following
the effective date of the Registration Statement, so long as the Company remains
subject to the periodic reporting requirements under Sections 13 or 15(d) of the
Exchange Act;

              (b)  file with the SEC in a timely manner all reports and other
documents required of the Company under the Securities Act and the Exchange Act;
and

              (c)  furnish to any Holder, so long as the Holder owns any
Registrable Securities, forthwith upon request a written statement by the
Company that it has complied with the reporting requirements of SEC Rule 144.

         1.6  Indemnification.

              (a)  Parent will, without limitation as to time, indemnify and
hold harmless, to the full extent permitted by law, each Holder, each of its
officers and directors and partners, and each person controlling such Holder
within the meaning of Section 15 of the Securities Act, with respect to which
registration, qualification or compliance has been effected pursuant to this
Section 1, and each underwriter, if any, and each person who controls any
---------
underwriter within the meaning of Section 15 of the Securities Act or the
Exchange Act, against all expenses, claims, losses, damages or liabilities (or
actions in respect thereof), including any of the foregoing incurred in
settlement of any litigation, commenced or threatened, arising out of or based
on any of the following statements, omissions or violations, or allegations
thereof (any of which, a "Violation"): (i) any untrue statement (or alleged
                          ---------
untrue statement) of a material fact contained in any registration

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statement, prospectus, offering circular or other document, or any amendment or
supplement thereto, incident to any such registration, qualification or
compliance, (ii) any omission (or alleged omission) to state therein a material
fact required to be stated therein or necessary to make the statements therein,
in light of the circumstances in which they were made, not misleading or (iii)
any violation by Parent of the Securities Act, the Exchange Act, state
securities law or any rule or regulation promulgated under such laws applicable
to Parent in connection with any such registration, qualification or compliance,
and within a reasonable period Parent will reimburse each such Holder, each of
its officers and directors, and each person controlling such Holder, each such
underwriter and each person who controls any such underwriter, for any legal and
any other expenses reasonably incurred in connection with investigating,
preparing or defending any such claim, loss, damage, liability or action;
provided that Parent will not be liable in any such case to the extent that any
such claim, loss, damage, liability or expense arises out of or is based on (x)
any untrue statement or omission or alleged untrue statement or omission, made
in reliance upon and in conformity with written information furnished by the
Holder to Parent for use in the Registration Statement or (y) a material
misstatement or omission of fact contained in any preliminary prospectus if a
final, amended or supplemental prospectus which corrects such omission or
misstatement is delivered by Parent to such person at or prior to the written
confirmation of the sale giving rise to the Violation or alleged Violation.

              (b)  Each Holder will, if Registrable Securities held by such
Holder are included in the securities as to which such registration,
qualification or compliance is being effected, indemnify Parent, each of its
directors and officers, each underwriter, if any, of Parent's securities covered
by such a registration statement, each person who controls Parent or such
underwriter within the meaning of Section 15 of the Securities Act, and each
other such Holder, each of its officers and directors and each person
controlling such Holder within the meaning of Section 15 of the Securities Act,
against all claims, losses, damages and liabilities (or actions in respect
thereof) arising out of or based on a Violation, and within a reasonable period
will reimburse Parent, such Holders, such directors, officers, persons,
underwriters or control persons for any legal or any other expenses reasonably
incurred in connection with investigating or defending any such claim, loss,
damage, liability or action, in each case to the extent, but only to the extent,
that such untrue statement (or alleged untrue statement) or omission (or alleged
omission) is made in such registration statement, prospectus, offering circular
or other document in reliance upon and in conformity with written information
furnished by the Holder to Parent for use in the Registration Statement.
Notwithstanding the foregoing, the liability of each Holder under this
subsection (b) shall be limited in an amount equal to the gross proceeds before
expenses and commissions to each Holder received for the shares sold by such
Holder, unless such liability arises out of or is based on willful misconduct by
such Holder.


              (c)  Each party entitled to indemnification under this Section 1.6
                                                                     -----------
(the "Indemnified Party") shall give notice to the party required to provide
      -----------------
indemnification (the "Indemnifying Party") promptly after such Indemnified Party
                      ------------------
has actual knowledge of any claim as to which indemnity may be sought, and shall
permit the Indemnifying Party to assume the defense of any such claim or any
litigation resulting therefrom, provided that counsel for the Indemnifying
Party, who shall conduct the defense of such claim or litigation, shall be
approved by the Indemnified Party (whose approval shall not unreasonably be
withheld), and the Indemnified Party may participate in such defense at such
party's expense, and provided further that the failure of any

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Indemnified Party to give notice as provided herein shall not relieve the
Indemnifying Party of its obligations under this Section 1 unless the failure to
                                                 ---------
give such notice is materially prejudicial to an Indemnifying Party's ability to
defend such action and provided further, that the Indemnifying Party shall not
assume the defense for matters as to which there is a conflict of interest or
separate and different defenses. No Indemnifying Party, in the defense of any
such claim or litigation, shall, except with the consent of each Indemnified
Party, consent to entry of any judgment or enter into any settlement which does
not include as an unconditional term thereof the giving by the claimant or
plaintiff to such Indemnified Party of a release from all liability in respect
to such claim or litigation.

         1.7  Information by Holder.  The Holder or Holders of Registrable
              ---------------------
Securities included in any registration shall furnish to Parent such information
regarding such Holder or Holders, the Registrable Securities held by them and
the distribution proposed by such Holder or Holders as Parent may request in
writing and as shall be required in connection with any registration,
qualification or compliance referred to in this Section 1.
                                                ---------

         1.8  Transfer of Registration Rights.  The rights to have securities
              -------------------------------
registered granted Holders under Section 1.2 may be assigned to a transferee or
                                 -----------
assignee which acquires at least 1000 shares of Registrable Securities in
connection with any transfer or assignment of Registrable Securities by the
Holders.

                                   SECTION 2

                                 Miscellaneous

         2.1  Governing Law.  This Agreement shall be governed in all respects
              -------------
by the internal laws of the State of California.

         2.2  Survival.  The covenants and agreements made herein shall survive
              --------
the closing of the transactions contemplated hereby.

         2.3  Successors and Assigns.  Except as otherwise provided herein, the
              ----------------------
provisions hereof shall inure to the benefit of, and be binding upon, the
successors, assigns, heirs, executors and administrators of the parties hereto.

         2.4  Entire Agreement; Amendment. This Agreement and the Merger
              ---------------------------
Agreement constitute the full and entire understanding and agreement between the
parties with regard to the subjects hereof and thereof, and no party shall be
liable or bound to any other party in any manner by any warranties,
representations or covenants except as specifically set forth herein or therein.
Except as expressly provided herein, neither this Agreement nor any term hereof
may be amended, waived, discharged or terminated other than by a written
instrument signed by the party against whom enforcement of any such amendment,
waiver, discharge or termination is sought; provided, however, that holders of a
majority of the Registrable Securities may, with Parent's prior written consent,
waive, modify or amend on behalf of all holders, any provisions hereof.

         2.5  Notices, etc.  All notices and other communications required or
              ------------
permitted hereunder shall be in writing and shall be mailed by registered or
certified mail, postage prepaid,

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<PAGE>

telecopied or otherwise delivered by hand or by messenger, addressed (a) if to a
Holder, at such address as such Holder shall have furnished Parent in writing,
or, until any such holder so furnishes an address to Parent, then to and at the
address of the last Holder who has so furnished an address to Parent, or (b) if
to Parent, one copy should be sent to its address set forth on the cover page of
this Agreement and addressed to the attention of Mr. Richard Harrison, or at
such other address as Parent shall have furnished to the Holders.

     Each such notice or other communication shall for all purposes of this
Agreement be treated as effective or having been given when delivered if
delivered personally, or, if sent by mail, at the earlier of its receipt or 72
hours after the same has been deposited in a regularly maintained receptacle for
the deposit of the United States mail, addressed and mailed as aforesaid.

         2.6  Delays or Omissions.  Except as expressly provided herein, no
              -------------------
delay or omission to exercise any right, power or remedy accruing to any party
to this Agreement upon any breach or default of any other party under this
Agreement, shall impair any such right, power or remedy of such nondefaulting
party nor shall it be construed to be a waiver of any such breach or default, or
an acquiescence therein, or of or in any similar breach or default thereafter
occurring; nor shall any waiver of any single breach or default be deemed a
waiver of any other breach or default theretofore or thereafter occurring. Any
waiver, permit, consent or approval of any kind or character on the part of any
party of any breach or default under this Agreement, or any waiver on the part
of any holder of any provisions or conditions of this Agreement, must be in
writing and shall be effective only to the extent specifically set forth in such
writing. All remedies, either under this Agreement or by law or otherwise
afforded to any party to this Agreement, shall be cumulative and not
alternative.

         2.7  Counterparts.  This Agreement may be executed in any number of
              ------------
counterparts, each of which shall be enforceable against the parties actually
executing such counterparts, and all of which together shall constitute one
instrument.

         2.8  Severability.  In the event that any provision of this Agreement
              ------------
becomes or is declared by a court of competent jurisdiction to be illegal,
unenforceable or void, this Agreement shall continue in full force and effect
without said provision; provided that no such severability shall be effective if
it materially changes the economic benefit of this Agreement to any party.

         2.9  Titles and Subtitles.  The titles and subtitles used in this
              --------------------
Agreement are used for convenience only and are not considered in construing or
interpreting this Agreement.

                           (Signature Page Follows)

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<PAGE>

The foregoing Agreement is hereby executed as of the date first above written.

                                 "PARENT"

                                 INTERPORE INTERNATIONAL, INC.
                                 a Delaware Corporation

                                 By:/s/ David C. Mercer
                                    --------------------------------------------
                                    Name:  David C. Mercer
                                    Title: Chief Executive Officer

                                 "TARGET SHAREHOLDER REPRESENTATIVE"


                                 By:/s/ Eric Major
                                    --------------------------------------------
                                    Eric Major, on behalf of himself and the
                                    Shareholders



               (Signature Page to Registration Rights Agreement)

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