Exhibit 4.31

CODE OF BUSINESS CONDUCT AND ETHICS

As
of March 7, 2003

Introduction

This Code of Business Conduct and Ethics (the "Code") is adopted for the purpose of promoting honest and ethical conduct; ensuring compliance with applicable
governmental laws, rules and regulations; avoiding conflicts of interest; providing an avenue for disclosure of any violations of the Code; and providing accountability for adherence to the Code.

The
Code is applicable to all Centerpulse directors, officers and employees (the "Individuals"). In recognition of the important and elevated role in corporate governance (including but
not limited to their responsibility and authority to protect, balance and preserve the interest of Centerpulse and its stakeholders), this policy is specifically made applicable to Centerpulse's
principal executive officer and senior financial officers. Senior financial officers shall include the principal financial officers, controllers, principal accounting officers and other persons that
perform similar functions.

The
Code covers a wide range of business practices and procedures. It does not cover every issue that may arise, but it sets out basic principles to guide all Individuals. All
Individuals must conduct themselves accordingly and avoid even the appearance of improper behavior.

Adherence
with the Code is a condition of employment for employees and, for officers and directors, a condition of holding your respective position. If a law conflicts with a policy in
this Code, you must comply with the law; however, if a local custom or policy conflicts with this Code, you must comply with the Code. If you have any questions about the Code, you should consult with
your supervisor, a human resources representative, the Legal Department, or the Ethics and Compliance Administrator.

Each
Individual is provided with a copy of this policy at the beginning of his or her relationship with Centerpulse. However, additional copies of these policies are available from the
Human Resources Department, the Legal Department or the Ethics and Compliance Administrator.

In
addition to the Code, employees of Centerpulse's U.S. and Canadian entities are subject to the Centerpulse USA Inc. Business Conduct Guidelines.

1.    Compliance with Laws, Rules and Regulations

Obeying the law, both in letter and in spirit, is the foundation on which Centerpulse's ethical standards are built. All Individuals must respect and obey all
national and local laws, rules and regulations that apply to Centerpulse's business. All Individuals should understand the laws and regulations, which apply to them in the performance of their duties
and ensure that Centerpulse complies with the national and local laws, rules and regulations of the countries in which we operate. Questions concerning any legal responsibility should be referred to
the Legal Department.

2.    Insider Trading

Laws in some countries prohibit the use of nonpublic information obtained as a consequence of employment (including information about customers, suppliers,
competitors, and proposed acquisitions or divestitures) for the personal profit of an Individual or of anyone as a result of association with an Individual. Use for personal profit includes taking
advantage of such information by trading or providing information for others to trade in securities of a publicly traded company. Centerpulse's Insider Trading Policy and other restrictions on trading
imposed by company policy from time to time further address this issue and are applicable to the Individuals.

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3.    Conflicts of Interest

Conflicts of interest are prohibited as a matter of Centerpulse policy. A "conflict of interest" exists when an Individual's private interest interferes or
appears to interfere in any way with the interests of Centerpulse or their ability to devote full attention to the requirements of his or her position with Centerpulse and to perform his or her duties
objectively and effectively. A conflict of interest also arises when an Individual or member of his or her family receives improper personal benefits as a result of his or her position in the company.
Loans to or guarantees of obligations of Individuals and their family members are of special concern and may create a conflict of interest. As part of this policy, Individuals are prohibited from
(a) taking for themselves personally opportunities that are discovered through the use of corporate property, information or position; (b) using corporate property, information, or
position for improper personal gain; and (c) compete with Centerpulse, directly or indirectly. Individuals owe a duty to Centerpulse to advance Centerpulse's legitimate interests when the
opportunity to do so arises.

It
is not possible to define all situations which, would constitute a conflict with the interests of Centerpulse. However, the following activities are presented as a guide for
determining circumstances which might create conflicts of interest:



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Conflicts
of interest may not always be clear, so if there is a question, consult with your supervisor, a human resources representative, the Legal Department, or the Ethics
Administrator.

4.    Competition and Fair Dealing

Centerpulse seeks to outperform its competition fairly and honestly and seeks competitive advantages through superior performance, never through unethical or
illegal business practices. Stealing proprietary information, possessing trade secrets that were obtained without the owner's consent, or inducing such disclosures by past or present employees of
other companies is prohibited. Individuals shall (a) respect the rights of and deal fairly with Centerpulse's business investors, suppliers, competitors and employees; and (b) avoid
taking unfair advantage of anyone through manipulation, concealment, abuse of privileged information, misrepresentation of material facts, or any other unfair-dealing practice.

5.    Protection and Use of Assets

Centerpulse has a wide variety of assets, which are of significant value to its competitiveness and success. These assets include our valuable confidential
information as well as our physical assets. Protecting these assets and assuring their efficient use are important and fundamental responsibilities of each Individual. The loss, theft, misuse or waste
of Centerpulse's assets could jeopardize the future of the Company.



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6.    Discrimination and Harassment

The diversity of employees is a tremendous asset to Centerpulse. Centerpulse is firmly committed to providing equal opportunity in all aspects of employment and
shall not tolerate any unlawful discrimination or harassment.

7.    Compliance and Discipline

Centerpulse is determined to operate according to the highest possible standards of business ethics and conduct. This Code is important to Centerpulse and is to
be taken seriously by all Individuals. Failure to comply with this Code can result in disciplinary action, which may include, but not limited, the termination of employment or removal from your
position as an officer or director. Failure to comply may also result in Centerpulse referring the matter criminal prosecution and/or seeking reimbursement of any losses or damages resulting from the
violation.

As
with all matters involving disciplinary action, principles of fairness will apply. Any Individual charged with a violation of this Code will be afforded an opportunity to explain his
or her actions before disciplinary action is taken. This Code will be enforced at all levels, fairly and without prejudice.

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Consistent with its obligations under the law, and within the enforcement process established in this Code, Centerpulse will keep confidential the identity of employees about or against whom
allegations of violations are brought, unless or until it has been determined that a violation has occurred. Similarly, to the extent possible and permitted by law, Centerpulse will keep confidential
the identity of anyone reporting a possible violation.

8.    Waivers of the Code of Business Conduct and Ethics

For the Directors and Members of the Executive Committee, a waiver of this Code may be made only by the Chairman of the Board, the Chairman of the Board's
Corporate Governance Committee or the Lead Director. Members of the Executive Committee, the Compliance Officer of a Business Unit or the Ethics and Compliance Administrator, can approve other
waivers. Waivers will be promptly disclosed as required by law or stock exchange regulation.

9.    Business Ethics and Compliance Administrator

Martin Schmid is Centerpulse's Business Ethics and Compliance Administrator and is available for any assistance and information deemed necessary. The telephone
number is +41 1 306 9875; the e-mail address is martin.schmid@centerpulse.com.

10.  Reporting

Individuals are encouraged to talk to their immediate supervisor, a human resources representative, the Legal Department, or the Ethics and Compliance
Administrator if you (a) observe any behavior which you believe is illegal, unethical or otherwise in violation of this Code; or (b) need help or information regarding this Code or a
potential course of action in a particular situation.

All
reports will be held in confidence if requested and to the extent permitted by law. Centerpulse shall protect Individuals who in good faith provide information or otherwise report
misconduct in violation of this Code from retaliation or other adverse employment action.

11.  Additional local requirements

Centerpulse has additional local policies in countries with further requirements regarding the Code of Business conduct and ethics. In the case of conflicting
regulations the more stringent regulation shall prevail.

|Zurich, March 7, 2003                |  |                               
|------------------------------------ |  | ------------------------------
|                                     |  |                               
|Dr. Max Link (Chairman of the Board) |  | Christian Stambach (Secretary)

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