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                                                                     Exhibit 3.1

                                                                  EXECUTION COPY

                                    RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                              ZIMMER HOLDINGS, INC.

          The corporation was incorporated under the name "Zodiac Holdings,
Inc." by the filing of its original Certificate of Incorporation with the
Secretary of State of Delaware on January 12, 2001. The present name of the
corporation is Zimmer Holdings, Inc., as changed by the filing of a Certificate
of Amendment of Certificate of Incorporation with the Secretary of State of
Delaware on March 21, 2001. This Restated Certificate of Incorporation of the
corporation, which both restates and further amends the provisions of the
corporation's Certificate of Incorporation, was duly adopted in accordance with
the provisions of Sections 242 and 245 of the General Corporation Law of the
State of Delaware (the "DGCL") and by the written consent of its stockholders in
accordance with Section 228 of the DGCL. The Certificate of Incorporation of the
corporation is hereby amended and restated to read in its entirety as follows:

                                    ARTICLE I

                                      NAME

          SECTION 1.01. The name of the Corporation (which is hereinafter
referred to as the "CORPORATION") is "Zimmer Holdings, Inc."

                                   ARTICLE II

                                REGISTERED AGENT

          SECTION 2.01. The address, including street, number, city, and county,
of the registered office of the Corporation in the State of Delaware is
Corporation Trust Center, 1209 Orange Street, in the City of Wilmington, County
of New Castle. The name of its registered agent at such address is the
Corporation Trust Company.

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                                   ARTICLE III

                                     PURPOSE

          SECTION 3.01. The purpose of the Corporation shall be to engage in any
lawful act or activity for which corporations may be organized and incorporated
under the DGCL.

                                   ARTICLE IV

                                  CAPITAL STOCK

          SECTION 4.01. The Corporation shall be authorized to issue 1.25
billion shares of capital stock, of which 1 billion shares shall be shares of
common stock, $0.01 par value per share ("COMMON STOCK"), and 250 million shares
shall be shares of preferred stock, $0.01 par value per share ("PREFERRED
STOCK").

          SECTION 4.02. PREFERRED STOCK. The Preferred Stock may be issued from
time to time in one or more series. The Board of Directors of the Corporation
(the "BOARD OF DIRECTORS" and each member thereof, a "DIRECTOR") is hereby
authorized to provide for the issuance of shares of Preferred Stock in series
and, by filing a certificate pursuant to the DGCL (a "PREFERRED STOCK
DESIGNATION"), to establish from time to time the number of shares to be
included in each such series, and to fix the designation, powers, privileges,
preferences and rights of the shares of each such series and the qualifications,
limitations and restrictions thereof. The authority of the Board of Directors
with respect to each series shall include, but not be limited to, determination
of the following:

          (a) the designation of the series, which may be by distinguishing
number, letter or title;

          (b) the number of shares of the series, which number the Board of
Directors may thereafter, except where otherwise provided in the applicable
Preferred Stock Designation, increase or decrease, but not below the number of
shares thereof then outstanding;

          (c) whether dividends, if any, shall be cumulative or noncumulative,
and, in the case of shares of any series having cumulative dividend rights, the
date or dates or method of determining the date or dates from which dividends on
the shares of such series shall be cumulative;

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          (d) the rate of any dividends, or method of determining such
dividends, payable to the holders of the shares of such series, any conditions
upon which such dividends shall be paid and the date or dates or the method for
determining the date or dates upon which such dividends shall be payable;

          (e) the price or prices, or method of determining such price or
prices, at which, the form of payment of such price or prices (which may be
cash, property or rights, including securities of the same or another
corporation or other entity) for which, the period or periods within which and
the terms and conditions upon which the shares of such series may be redeemed,
in whole or in part, at the option of the Corporation or at the option of the
holder or holders thereof or upon the happening of a specified event or events,
if any;

          (f) the obligation, if any, of the Corporation to purchase or redeem
shares of such series pursuant to a sinking fund or otherwise and the price or
prices at which, the form of payment of such price or prices (which may be cash,
property or rights, including securities of the same or another corporation or
other entity) for which, the period or periods within which and the terms and
conditions upon which the shares of such series shall be redeemed or purchased,
in whole or in part, pursuant to such obligation;

          (g) the amounts payable out of the assets of the Corporation on and
the preferences, if any, of shares of the series in the event of any voluntary
or involuntary liquidation, dissolution or winding up of the affairs of the
Corporation;

          (h) provisions, if any, for the conversion or exchange of the shares
of such series, at any time or times at the option of the holder or holders
thereof or at the option of the Corporation or upon the happening of a specified
event or events, into shares of any other class or classes or any other series
of the same or any other class or classes of stock, or any other security, of
the Corporation, or any other corporation or other entity, and the price or
prices or rate or rates of conversion or exchange and any adjustments applicable
thereto, the date or dates as of when such shares will be converted or exchanged
and all other terms and conditions upon which such conversion or exchange may be
made;

          (i) restrictions on the issuance of shares of the same series or of
any other class or series, if any; and

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          (j) the voting rights, if any, of the holders of shares of the series.

          SECTION 4.03. COMMON STOCK. (a) The Common Stock shall be subject to
the express terms of the Preferred Stock and any series thereof. Each share of
Common Stock shall be equal to every other share of Common Stock, except as
otherwise provided herein or required by law.

          (b) Shares of Common Stock authorized hereby shall not be subject to
preemptive rights. The holders of shares of Common Stock now or hereafter
outstanding shall have no preemptive right to purchase or have offered to them
for purchase any of such authorized but unissued shares, or any shares of
Preferred Stock, Common Stock or other equity securities issued or to be issued
by the Corporation.

          (c) The holders of shares of Common Stock shall be entitled to one
vote for each such share upon all proposals presented to the stockholders on
which the holders of Common Stock are entitled to vote. Except as otherwise
provided by law or by the resolution or resolutions adopted by the Board of
Directors designating the rights, powers and preferences of any series of
Preferred Stock, the Common Stock shall have the exclusive right to vote for the
election of Directors and for all other purposes, and holders of Preferred Stock
shall not be entitled to receive notice of any meeting of stockholders at which
they are not entitled to vote. The number of authorized shares of Preferred
Stock may be increased or decreased (but not below the number of shares thereof
then outstanding) by the affirmative vote of the holders of a majority of the
outstanding Common Stock, without a vote of the holders of the Preferred Stock,
or of any series thereof, unless a vote of any such holders is required pursuant
to any Preferred Stock Designation.

          (d) Subject to the rights of any class or series of stock having a
preference over the Common Stock as to dividends, the holders of the shares of
Common Stock shall be entitled to receive such dividends and other distributions
in cash, stock or property of the Corporation as may be declared on the Common
Stock by the Board of Directors at any time or from time to time out of any
funds legally available therefor.

          (e) In the event of any voluntary or involuntary liquidation,
dissolution or winding up of the Corporation, subject to the rights of any class
or series of stock having a preference over the Common Stock as to dividends or
upon liquidation, dissolution or winding up, the holders of shares of Common
Stock shall be entitled to receive all of

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the remaining assets of the Corporation available for distribution to its
stockholders, ratably in proportion to the number of shares of Common Stock held
by them.

          (f) The Corporation shall be entitled to treat the person in whose
name any share of its stock is registered as the owner thereof for all purposes
and shall not be bound to recognize any equitable or other claim to, or interest
in, such share on the part of any other person, whether or not the Corporation
shall have notice thereof, except as expressly provided by applicable law.

                                    ARTICLE V

                               STOCKHOLDER ACTION

          SECTION 5.01. Effective as of the time at which Bristol-Myers Squibb
Company, a Delaware corporation, shall cease to be the beneficial owner of an
aggregate of at least a majority of the then outstanding shares of Common Stock
(the "TRIGGER DATE"), any action required or permitted to be taken by the
stockholders of the Corporation must be effected at a duly called annual or
special meeting of such holders and may not be effected by any consent in
writing by such holders, except this provision shall not apply to any action
taken by the stockholders of the Corporation after the Trigger Date in respect
of a record date occurring prior to the Trigger Date. Effective as of the
Trigger Date, except as otherwise required by law and subject to the rights of
the holders of any class or series of stock having a preference over the Common
Stock as to dividends or upon liquidation, dissolution or winding up, special
meetings of stockholders of the Corporation for any purpose or purposes may be
called only by the Board of Directors pursuant to a resolution stating the
purpose or purposes thereof approved by a majority of the total number of
Directors which the Corporation would have if there were no vacancies or
unfilled newly-created directorships (the "WHOLE BOARD") or by the Chairman of
the Board of Directors and, effective as of the Trigger Date, any power of
stockholders to call a special meeting is specifically denied. No business other
than that stated in the notice shall be transacted at any special meeting of
stockholders. Notwithstanding anything contained in this Restated Certificate of
Incorporation to the contrary, the affirmative vote of the holders of at least
80% of the voting power of all shares of the Corporation entitled to vote
generally in the election of Directors (the "VOTING STOCK") then outstanding,
voting together as a single class, shall be required to alter,

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amend, adopt any provision inconsistent with or repeal this Article V.

                                   ARTICLE VI

                              ELECTION OF DIRECTORS

          SECTION 6.01. Unless and except to the extent that the By-laws of the
Corporation (the "BY-LAWS") shall so require, the election of Directors of the
Corporation need not be by written ballot.

                                   ARTICLE VII

                               BOARD OF DIRECTORS

          SECTION 7.01. NUMBER, ELECTION AND TERMS. Except as otherwise fixed by
or pursuant to the provisions of Article IV hereof relating to the rights of the
holders of any class or series of stock having a preference over the Common
Stock as to dividends or upon liquidation, dissolution or winding up to elect
additional Directors under specified circumstances, the number of the Directors
shall be fixed from time to time exclusively pursuant to a resolution adopted by
a majority of the Whole Board (but shall not be less than three). The Directors,
other than those who may be elected by the holders of any class or series of
stock having a preference over the Common Stock as to dividends or upon
liquidation, dissolution or winding up, shall be classified, with respect to the
time for which they severally hold office, into three classes, as nearly equal
in number as possible, one class to be originally elected for a term expiring at
the first annual meeting of stockholders following the effectiveness of this
Restated Certificate of Incorporation, another class to be originally elected
for a term expiring at the second annual meeting of stockholders following the
effectiveness of this Restated Certificate of Incorporation, and another class
to be originally elected for a term expiring at the third annual meeting of
stockholders following the effectiveness of this Restated Certificate of
Incorporation, with each Director to hold office until such person's successor
is duly elected and qualified. At each annual meeting of stockholders, Directors
elected to succeed those Directors whose terms then expire shall be elected for
a term of office to expire at the third succeeding annual meeting of
stockholders after their election, with each Director to hold office until such
person's successor shall have been duly elected and qualified.

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          SECTION 7.02. STOCKHOLDER NOMINATION OF DIRECTOR CANDIDATES;
STOCKHOLDER PROPOSAL OF BUSINESS. Advance notice of stockholder nominations for
the election of Directors and of the proposal of business by stockholders shall
be given in the manner provided in the By-laws, as amended and in effect from
time to time.

          SECTION 7.03. NEWLY CREATED DIRECTORSHIPS AND VACANCIES. Except as
otherwise provided for or fixed by or pursuant to the provisions of Article IV
hereof relating to the rights of the holders of any class or series of stock
having a preference over the Common Stock as to dividends or upon liquidation,
dissolution or winding up to elect Directors under specified circumstances,
newly created directorships resulting from any increase in the number of
Directors and any vacancies on the Board of Directors resulting from death,
resignation, disqualification, removal or other cause shall only be filled by
the affirmative vote of a majority of the remaining Directors then in office,
even though less than a quorum of the Board of Directors, and not by the
stockholders. Any Director elected in accordance with the preceding sentence
shall serve for the remainder of the full term of the class of Directors in
which the new directorship was created or the vacancy occurred and until such
Director's successor shall have been duly elected and qualified. No decrease in
the number of Directors constituting the Board of Directors shall shorten the
term of any incumbent Director.

          SECTION 7.04. REMOVAL. Subject to the rights of any class or series of
stock having a preference over the Common Stock as to dividends or upon
liquidation, dissolution or winding up to elect Directors under specified
circumstances, any Director may be removed from office only for cause and only
by the affirmative vote of the holders of at least 80% of the voting power of
all Voting Stock then outstanding, voting together as a single class.

          SECTION 7.05. AMENDMENT, REPEAL, ETC. Notwithstanding anything
contained in this Restated Certificate of Incorporation to the contrary, the
affirmative vote of the holders of at least 80% of the voting power of all
Voting Stock then outstanding, voting together as a single class, shall be
required to alter, amend, adopt any provision inconsistent with or repeal this
Article VII.

          SECTION 7.06. OTHER PROVISIONS. Notwithstanding any other provision of
this Article VII, andexcept as otherwise required by law, whenever the holders
of one or more series of Preferred Stock shall have the right, voting

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separately as a class, to elect one or more Directors of the Corporation, the
term of office, the filling of vacancies, the removal from office and other
features of such directorships shall be governed by the terms of this Restated
Certificate of Incorporation (including any Preferred Stock Designation). During
any period when the holders of any series of Preferred Stock have the right to
elect additional Directors as provided for or fixed pursuant to the provisions
of Article IV hereof, then upon commencement and for the duration of the period
during which such right continues: (i) the then otherwise total authorized
number of Directors of the Corporation shall automatically be increased by such
specified number of Directors, and the holders of such Preferred Stock shall be
entitled to elect the additional Directors so provided for or fixed pursuant to
said provisions, and (ii) each such additional Director shall serve until such
Director's successor shall have been duly elected and qualified, or until such
Director's right to hold such office terminates pursuant to said provisions,
whichever occurs earlier, subject to his earlier death, disqualification,
resignation or removal. Except as otherwise provided by the Whole Board in the
resolution or resolutions establishing such series, whenever the holders of any
series of Preferred Stock having such right to elect additional Directors are
divested of such right pursuant to the provisions of such stock, the terms of
office of all such additional Directors elected by the holders of such stock, or
elected to fill any vacancies resulting from the death, resignation,
disqualification or removal of such additional Directors, shall forthwith
terminate and the total authorized number of Directors of the Corporation shall
be reduced accordingly.


                                  ARTICLE VIII

                                     BY-LAWS

          SECTION 8.01. The By-laws may be altered or repealed and new By-laws
may be adopted (a) at any annual or special meeting of stockholders, by the
affirmative vote of the holders of a majority of the voting power of the Voting
Stock then outstanding, voting together as a single class; PROVIDED, HOWEVER,
that any proposed alteration or repeal of, or the adoption of any By-law
inconsistent with, Section 2.02, 2.07 or 8.01 of the By-laws, by the
stockholders shall require the affirmative vote of the holders of at least 80%
of the voting power of all Voting Stock then outstanding, voting together as a
single class; PROVIDED, FURTHER, HOWEVER, that in the case of any such
stockholder action at a special meeting of stockholders, notice of the proposed

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alteration, repeal or adoption of the new By-law or By-laws must be contained in
the notice of such special meeting, or (b) by the affirmative vote of a majority
of the Whole Board. Notwithstanding anything contained in this Restated
Certificate of Incorporation to the contrary, the affirmative vote of the
holders of at least 80% of the voting power of all Voting Stock then
outstanding, voting together as a single class shall be required to alter,
amend, adopt any provision inconsistent with or repeal this Article VIII.

                                   ARTICLE IX

                    AMENDMENT OF CERTIFICATE OF INCORPORATION

          SECTION 9.01. The Corporation reserves the right at any time from time
to time to amend, alter, change or repeal any provision contained in this
Restated Certificate of Incorporation, and any other provisions authorized by
the laws of the State of Delaware at the time in force may be added or inserted,
in the manner now or hereafter prescribed by law; and, except as set forth in
Article X, all rights, preferences and privileges of whatsoever nature conferred
upon stockholders, Directors or any other persons whomsoever by and pursuant to
this Restated Certificate of Incorporation in its present form or as hereafter
amended are granted subject to the right reserved in this Article.
Notwithstanding anything contained in this Restated Certificate of Incorporation
to the contrary, the affirmative vote of the holders of at least 80% of the
Voting Stock then outstanding, voting together as a single class, shall be
required to alter, amend, adopt any provision inconsistent with or repeal
Article V, VII, VIII or this sentence.

                                    ARTICLE X

                       LIMITED LIABILITY; INDEMNIFICATION

          SECTION 10.01.LIMITED LIABILITY OF DIRECTORS. A Director shall not be
personally liable to the Corporation or its stockholders for monetary damages
for breach of fiduciary duty as a Director, except, if required by the DGCL, as
amended from time to time, for liability (a) for any breach of the Director's
duty of loyalty to the Corporation or its stockholders, (b) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (c) under Section 174 of the DGCL, or (d) for any transaction
from which the Director

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derived an improper personal benefit. Neither the amendment nor repeal of this
Section 10.01 shall eliminate or reduce the effect of this Section 10.01 in
respect of any matter occurring, or any cause of action, suit or claim that, but
for this Section 10.01 would accrue or arise, prior to such amendment or repeal.

          SECTION 10.02.INDEMNIFICATION AND INSURANCE. (a) RIGHT TO
INDEMNIFICATION. Each person who was or is made a party or is threatened to be
made a party to or is involved in any threatened, pending or completed action,
suit or proceeding, whether civil, criminal, administrative or investigative
(hereinafter a "PROCEEDING"), by reason of the fact that such person, or a
person of whom such person is the legal representative, is or was a Director or
officer of the Corporation or, while a Director or officer of the Corporation,
is or was serving at the request of the Corporation as a director, officer,
employee or agent of another corporation or of a partnership, joint venture,
trust or other enterprise, including service with respect to employee benefit
plans, whether the basis of such proceeding is alleged action in an official
capacity as a Director, officer, employee or agent or in any other capacity
while serving as a Director, officer, employee or agent, shall be indemnified
and held harmless by the Corporation to the fullest extent authorized by the
DGCL, as the same exists or may hereafter be amended, against all expense,
liability and loss (including attorneys' fees, judgments, fines, amounts paid or
to be paid in settlement, and excise taxes or penalties arising under the
Employee Retirement Income Security Act of 1974, as in effect from time to time)
reasonably incurred or suffered by such person in connection therewith if such
person acted in good faith and in a manner such person reasonably believed to be
in compliance with the standard of conduct set forth in Section 145 (or any
successor provision) of the DGCL and such indemnification shall continue as to a
person who has ceased to be a Director, officer, employee or agent and shall
inure to the benefit of such person's heirs, executors and administrators;
PROVIDED, HOWEVER, that, except as provided in paragraph (b) hereof, the
Corporation shall indemnify any such person seeking indemnification in
connection with a proceeding (or part thereof) initiated by such person only if
such proceeding (or part thereof) was authorized by the Board of Directors. The
Corporation shall pay the expenses incurred in defending any such proceeding in
advance of its final disposition with any advance payments to be paid by the
Corporation within 20 calendar days after the receipt by the Corporation of a
statement or statements from the claimant requesting such advance or advances
from time to time; PROVIDED, HOWEVER,

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that, if and to the extent the DGCL requires, the payment of such expenses
incurred by a Director or officer in such person's capacity as a Director or
officer (and not in any other capacity in which service was or is rendered by
such person while a Director or officer, including, without limitation, service
to an employee benefit plan) in advance of the final disposition of a
proceeding, shall be made only upon delivery to the Corporation of an
undertaking, by or on behalf of such Director or officer, to repay all amounts
so advanced if it shall ultimately be determined that such Director or officer
is not entitled to be indemnified under this Section 10.02 or otherwise. The
Corporation may, to the extent authorized from time to time by the Board of
Directors, grant rights to indemnification, and rights to have the Corporation
pay the expenses incurred in defending any proceeding in advance of its final
disposition, to any employee or agent of the Corporation to the fullest extent
of the provisions of this Article with respect to the indemnification and
advancement of expenses of Directors and officers of the Corporation.

          (b) RIGHT OF CLAIMANT TO BRING SUIT. If a claim under paragraph (a) of
this Section 10.02 is not paid in full by the Corporation within 30 calendar
days after a written claim has been received by the Corporation, the claimant
may at any time thereafter bring suit against the Corporation to recover the
unpaid amount of the claim and, if successful in whole or in part, the claimant
shall be entitled to be paid also the expense of prosecuting such claim. It
shall be a defense to any such action (other than an action brought to enforce a
claim for expenses incurred in defending any proceeding in advance of its final
disposition where the required undertaking, if any is required, has been
tendered to the Corporation) that the claimant has not met the standard of
conduct which makes it permissible under the DGCL for the Corporation to
indemnify the claimant for the amount claimed, but the burden of proving such
defense shall be on the Corporation. Neither the failure of the Corporation
(including its Board of Directors, independent legal counsel, or its
stockholders) to have made a determination prior to the commencement of such
action that indemnification of the claimant is proper in the circumstances
because the claimant has met the applicable standard of conduct set forth in the
DGCL, nor an actual determination by the Corporation (including its Board of
Directors, independent legal counsel, or its stockholders) that the claimant has
not met such applicable standard of conduct, shall be a defense to the action or
create a presumption that the claimant has not met the applicable standard of
conduct.

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          (c) NON-EXCLUSIVITY OF RIGHTS. The right to indemnification and the
payment of expenses incurred in defending a proceeding in advance of its final
disposition conferred in this Section 10.02 shall not be exclusive of any other
right which any person may have or hereafter acquire under any statute,
provision of the Restated Certificate of Incorporation, By-law, agreement, vote
of stockholders or disinterested Directors or otherwise. No repeal or
modification of this Article shall in any way diminish or adversely affect the
rights of any Director, officer, employee or agent of the Corporation hereunder
in respect of any occurrence or matter arising prior to any such repeal or
modification.

          (d) INSURANCE. The Corporation may maintain insurance, at its expense,
to protect itself and any person who is or was a Director, officer, employee or
agent of the Corporation or is or was serving at the request of the Corporation
as a director, officer, employee or agent of another corporation, partnership,
joint venture, trust or other enterprise against any such expense, liability or
loss, whether or not the Corporation would have the power to indemnify such
person against such expense, liability or loss under the DGCL.

          (e) SEVERABILITY. If any provision or provisions of this Article X
shall be held to be invalid, illegal or unenforceable for any reason whatsoever:
(i) the validity, legality and enforceability of the remaining provisions of
this Article X (including, without limitation, each portion of any paragraph of
this Article X containing any such provision held to be invalid, illegal or
unenforceable, that is not itself held to be invalid, illegal or unenforceable)
shall not in any way be affected or impaired thereby; and (ii) to the fullest
extent possible, the provisions of this Article X (including, without
limitation, each such portion of any paragraph of this Article X containing any
such provision held to be invalid, illegal or unenforceable) shall be construed
so as to give effect to the intent manifested by the provision held invalid,
illegal or unenforceable.

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          IN WITNESS WHEREOF, the Corporation has caused this Restated
Certificate of Incorporation to be signed by its duly authorized officer this
___________day of July 2001.

                                               ----------------------------
                                               Name:   J. Raymond Elliott
                                               Title:  President and Chief
                                                       Executive Officer