EXHIBIT 3.31

STATE OF DELAWARE
SECRETARY OF STATE
DIVISION OF CORPORATIONS
FILED 09:00 AM 07/23/1996
960213597 — 2642128

CERTIFICATE OF INCORPORATION

OF

COMMUNITY GP CORP.

The undersigned natural person of the age of eighteen years or more, acting as incorporator of a corporation under the Delaware General Corporation Law, as amended, hereby adopts the following Certificate of Incorporation for such corporation:

ARTICLE ONE

The name of the Corporation is Community GP Corp.

ARTICLE TWO

The period of its duration is perpetual.

ARTICLE THREE

The purpose for which the Corporation is organized is to engage in the transaction of any or all lawful business for which corporations may be incorporated under the Delaware General Corporation Law, as amended (the “Delaware General Corporation Law”).

ARTICLE FOUR

The aggregate number of shares which the Corporation shall have authority to issue is One Thousand (1,000) shares of $.01 par value per share common stock.

ARTICLE FIVE

The street address of its initial registered office is 1013 Centre Road, Wilmington, New Castle County, Delaware and the name of its initial registered agent at such address is Corporation Service Company.

ARTICLE SIX

Election of the Directors need not be by written ballot unless the Bylaws of the corporation shall so provide.

ARTICLE SEVEN

The name and address of the incorporator is:

Robin J. Payton
414 Union Street, Suite 1600
Nashville, TN 37219

ARTICLE EIGHT

To the fullest extent permitted by Delaware law, a director of the Corporation shall not be personally liable to the Corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except for liability (i) for any breach of the director’s 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 Delaware General Corporation Law, or (iv) for any transaction from which the director derives an improper personal benefit. If the Delaware General Corporation Law is amended hereafter to authorize corporate action further eliminating or limiting the personal liability of directors, then the liability of a director of the Corporation shall be eliminated or limited to the fullest extent permitted by the Delaware General Corporation Law, as so amended.

Any repeal or modification of the foregoing paragraph by the stockholders of the Corporation shall not adversely affect any right or protection of a director of the Corporation existing at the time of such repeal or modification.

ARTICLE NINE

A. Rights to Indemnification. Each person who was or is made a party or is threatened to be made a party to or is otherwise involved in any action, suit or proceeding, whether civil, criminal, administrative or investigative (hereinafter a “proceeding”), by reason of the fact that he or she, or a person of whom he or she is the legal representative, or is or was a director or officer of the. Corporation or is or was serving at the request of the Corporation as a director or officer of another corporation or of a partnership, joint venture, trust or other enterprise, including service with respect to an employee benefit plan (hereinafter an “indemnitee”), whether the basis of such proceeding is alleged action in an official capacity as a director or officer or in any other capacity while serving as a director or officer, shall be indemnified and held harmless by the Corporation to the fullest extent authorized by the Delaware General Corporation Law as the same exists or may hereafter be amended (hut, in the case of any such amendment, only to the extent that such amendment permits the Corporation to provide broader indemnification rights than permitted prior thereto), against all expense, liability and loss (including, without limitation, attorneys’ fees, judgments, fines, excise taxes or penalties and amounts paid or to be paid in settlement) incurred or suffered by such indemnitee in connection therewith and such indemnification shall continue with respect to an indemnitee who has ceased to be a director or officer and shall inure to the benefit of the indemnitee’s heirs, executors and administrators; provided, however, that except as provided in paragraph (B) of this Article Nine with respect to proceedings to enforce rights to indemnification, the Corporation shall indemnify any such indemnitee in connection with a proceeding initiated by such indemnitee only if such proceeding was authorized by the Board of Directors of the Corporation. The right to indemnification conferred in this Article shall be a contract right and shall include the right to be paid by the Corporation the expenses incurred in defending any such proceeding in advance of its final disposition (hereinafter an “advancement of expenses”); provided, however, that, if the Delaware

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General Corporation Law requires, an advancement of expenses incurred by an indemnitee shall be made only upon delivery to the Corporation of an undertaking (hereinafter an “undertaking”), by or on behalf of such indemnitee, to repay all amounts so advanced if it shall ultimately be determined by final judicial decision from which there is no further right to appeal (hereinafter a “final adjudication”) that such indemnitee is not entitled to he indemnified for such expenses under this Article or otherwise.

B. Right of Indemnitee to Bring Suit. If a claim under paragraph (A) of this Article is not paid in full by the Corporation within sixty days after a written claim. has been received by the Corporation (except in the case of a claim for an advancemeia of expenses, in which case the applicable period shall be twenty days), the indemnitee may at any time thereafter bring suit against the Corporation to recover the unpaid amount of the claim. If successful in whole or in part in any such suit, the indemnitee shall also be entitled to be paid the expense of prosecuting or defending such suit. In (i) any suit brought by the indemnitee to enforce a right to indemnification hereunder (but not a suit brought by the indemnitee to enforce a right to an advancement of expenses) it shall he a defense that, and (ii) in any suit by the Corporation to recover an advancement of expenses pursuant to the terms of an undertaking, the Corporation shall be entitled to recover such expenses upon a final adjudication that, the indemnitee has not met the applicable standard of conduct set forth in the Delaware General Corporation Law. 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 suit that indemnification of the indemnitee has met the applicable standard of conduct set forth in the Delaware General Corporation Law, nor an actual determination by the Corporation (including its Board of Directors, independent legal counsel or its stockholders) that the indemnitee has not met such applicable standard of conduct, or in the case of such a suit brought by the indemnitee, shall be a defense to such suit In any suit brought by the indemnitee to enforce a right to indemnification or to an advancement of expenses hereunder or by the Corporation to recover an advancement of expenses pursuant to the terms of an undertaking, the burden of proving that the indemnitee is not entitled under this Article or otherwise to be indemnified, or to such advancement of expenses, shall be on the Corporation.

C. Non-Exclusivity of Rights. The rights to indemnification and to the advancement of expenses conferred in this Article shall not be exclusive of any other right which any person may have or hereafter acquire under this Certificate of Incorporation or any Bylaw, agreement, vote of stockholders or disinterested directors or otherwise.

D. Insurance. The Corporation may maintain insurance, at its expense, to protect itself and any inclemnitee against any 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 Delaware General Corporation Law.

E. Indemnity of Employees and Agents of the Corporation. The Corporation may, to the extent authorized from time to time by the Board of Directors, grant rights to indemnification and to the advancement of expenses to any employee or agent of the Corporation to the fullest extent of the provisions of this Article or as otherwise permitted under the Delaware General Corporation Law with respect to the indemnification and advancement of expenses of directors and officers of the Corporation.

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ARTICLE TEN

The Bylaws of the Corporation may be altered, amended or repealed or new Bylaws may be adopted by the board of directors.

IN WITNESS WHEREOF, I have hereunto set my hand, this 22nd day of July, 1996.

/s/ Robin J. Payton
Robin J. Payton, Incorporator
414 Union Street
Suite 1600
Nashville, TN 37219

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State of Delaware
Secretary of State
Division of Corporations
Delivered 07:34 PM 11/05/2003
FILED 07:20 PM 11/05/2003
SRV 030712472 — 2642128 FILE

CERTIFICATE OF CHANGE OF LOCATION OF REGISTERED OFFICE AND OF REGISTERED AGENT

It is hereby certified that:

1. The name of the corporation (hereinafter called the “Corporation”) is: Community GP Corp.

2. The registered office of the Corporation within the State of Delaware is hereby changed to 9 East Loockerman Street, Suite 1B, City of Dover 19901, County of Kent.

3. The registered agent of the Corporation within the State of Delaware is hereby changed to National Registered Agents, Inc., the business office of which is identical with the registered office of the corporation as hereby changed.

4. The Corporation has authorized the changes hereinbefore set forth by resolution of its Board of Directors.

Signed on October 23, 2003

/s/ Kimberly A. Wright, Asst.Sec
Kimberly A. Wright

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