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                                                                    Exhibit 3.73

                          CERTIFICATE OF INCORPORATION
                                       OF
                                   THBS, INC.

         FIRST: The name of the corporation is THBS, Inc. (the "Corporation").

         SECOND: The registered office of the Corporation in the State of
Delaware is located at 1013 Centre Road, Wilmington, County of New Castle,
Delaware 19805. The registered agent of the Corporation at that address is
Corporation Service Company.

         THIRD: The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of the State of Delaware; provided that the Corporation's activities shall
be confined to the management and maintenance of its intangible investments and
the collection and distribution of the income from such investments or from
tangible property physically located outside Delaware, all as defined in, and in
such manner as to qualify for exemption from income taxation under, Section
1902(b)(8) of Title 30 of the Delaware Code, or under the corresponding
provision of any subsequent law.

         FOURTH: The Corporation shall have the authority to issue 1,000 shares
of common stock, having a par value of $1.00 per share.

         FIFTH: The Corporation shall indemnify directors and officers of the
Corporation to the fullest extent permitted by law.

         SIXTH: The directors of the Corporation shall incur no personal
liability to the Corporation or its stockholders for monetary damages for any
breach of fiduciary duty as a director, provided, however, that the directors of
the Corporation shall continue to be subject to liability (i) for any breach of
their duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the General Corporation Law of the
State of Delaware, or (iv) for any transaction from which the directors derived
any improper personal benefit. In discharging the duties of their respective
positions, the board of directors, committees of the board, individual directors
and any individual officers may, in considering the best interest of the
Corporation, consider the effects of any actions upon employees, suppliers and
customers of the Corporation, communities in which offices or other
establishments of the Corporation are located, and all other pertinent factors.
In addition, the personal liability of the directors shall further be limited to
the fullest extent permitted by any future amendments to Delaware law.

         SEVENTH: The business and affairs of the Corporation shall be managed
by or under the direction of the board of directors, the number of members of
which shall be set forth in the by-laws of the Corporation. The directors need
not be elected by ballot unless required by the by-laws of the Corporation.

         EIGHTH: Meetings of the stockholders will be held within the State of
Delaware. The books of the Corporation will be kept (subject to the provisions
contained in the General
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Corporation Law) in the State of Delaware at such place or places as may be
designated from time to time by the board of directors or in the by-laws of the
Corporation.

         NINTH: In the furtherance and not in limitation of the objects,
purposes and powers prescribed herein and conferred by the laws of the State of
Delaware, the board of directors is expressly authorized to make, amend and
repeal the by-laws.

         TENTH: The Corporation shall have no power and may not be authorized by
its stockholders or directors (i) to perform or omit to do any act that would
cause the Corporation to lose its status as a corporation exempt from the
Delaware Corporation income tax under Section 1902(b)(8) of Title 30 of the
Delaware Code, or under the corresponding provision of any subsequent law, or
(ii) to conduct any activities outside of Delaware which could result in the
Corporation being subject to tax outside of Delaware.

         ELEVENTH: The name and mailing address of the Incorporator is W. Dale
Amburn, London, Amburn & Thomforde, P.C., 1716 Clinch Avenue, Knoxville,
Tennessee 37916.

         TWELFTH: The powers of the Incorporator shall terminate upon election
of directors.

         I, THE UNDERSIGNED, being the Incorporator hereinbefore named for the
purpose of forming a corporation pursuant to the General Corporation Law of the
State of Delaware, do make this Certificate, hereby declaring and certifying
that this is my act and deed and the facts herein stated are true, and
accordingly have hereunto set my hand this 17th day of October, 1997.

                                             /s/ W. Dale Amburn
                                             -----------------------------------
                                             W. Dale Amburn, Incorporator


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