EXHIBIT 3.42


                                   BY - LAWS
                                   ---------

                                      OF
                                      --

                           LOCOMOTION THERAPY, INC.
                           ------------------------

                           (A Delaware Corporation)

                               ----------------

                                   ARTICLE I
                                   ---------

                                 STOCKHOLDERS
                                 ------------

          1.   CERTIFICATES REPRESENTING STOCK.  Every holder of stock in the
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corporation shall be entitled to have a certificate signed by, or in the name
of, the corporation by the Chairman or Vice-Chairman of the Board of Directors,
if any, or by the President or a Vice-President and by the Treasurer or an
Assistant Treasurer or the Secretary or an Assistant Secretary of the
corporation certifying the number of shares owned by him in the corporation. Any
and all signatures on any such certificate may be facsimiles.  In case any
officer, transfer agent, or registrar who has signed or whose facsimile
signature has been placed upon a certificate shall have ceased to be such
officer, transfer agent, or registrar before such certificate is issued, it may
be issued by the corporation with the same effect as if he were such officer,
transfer agent, or registrar at the date of issue.

               Whenever the corporation shall be authorized to issue more than
one class of stock or more than one series of any class of stock, and whenever
the corporation shall issue any shares of its stock as partly paid stock, the
certificates representing shares of any such class or series or of any such
partly paid stock shall set forth thereon the statements prescribed by the
General Corporation Law. Any restrictions on the transfer or registration of
transfer of any shares of stock of any class or series shall be noted
conspicuously on the certificate representing such shares.

               The corporation may issue a new certificate of stock in place of
any certificate theretofore issued by it, alleged to have been lost, stolen, or
destroyed, and the Board of Directors may require the owner of any lost, stolen,
or destroyed certificate, or his legal representative, to give the corporation a
bond sufficient to indemnify the corporation against any claim that may be made
against it on account of the alleged loss, theft, or destruction of any such
certificate or the issuance of any such new certificate.

          2.   FRACTIONAL SHARE INTERESTS.  The corporation may, but shall not
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be required to, issue fractions of a share.  If the corporation does not issue
fractions of a share, it shall (1) arrange for the disposition of fractional
interests by those entitled thereto, (2) pay in cash the fair value of fractions
of a share as of the time when those entitled to receive such fractions 

 
are determined, or (3) issue scrip or warrants in registered or bearer form
which shall entitle the holder to receive a certificate for a full share upon
the surrender of such scrip or warrants aggregating a full share. A certificate
for a fractional share shall, but scrip or warrants shall not unless otherwise
provided therein, entitle the holder to exercise voting rights, to receive
dividends thereon, and to participate in any of the assets of the corporation in
the event of liquidation. The Board of Directors may cause scrip or warrants to
be issued subject to the conditions that they shall become void if not exchanged
for certificates representing full shares before a specified date, or subject to
the conditions that the shares for which scrip or warrants are exchangeable may
be sold by the corporation and the proceeds thereof distributed to the holders
of scrip or warrants, or subject to any other conditions which the Board of
Directors may impose.

          3.   STOCK TRANSFERS.  Upon compliance with provisions restricting the
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transfer or registration of transfer of shares of stock, if any, transfers or
registration of transfers of shares of stock of the corporation shall be made
only on the stock ledger of the corporation by the registered holder thereof, or
by his attorney thereunto authorized by power of attorney duly executed and
filed with the Secretary of the corporation or with a transfer agent or a
registrar, if any, and on surrender of the certificate or certificates for such
shares of stock properly endorsed and the payment of all taxes due thereon.

          4.   RECORD DATE FOR STOCKHOLDERS.  For the purpose of determining the
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stockholders entitled to notice of or to vote at any meeting of stockholders or
any adjournment thereof, or entitled to receive payment of any dividend or other
distribution or the allotment of any rights, or entitled to exercise any rights
in respect of any change, conversion, or exchange of stock or for the purpose of
any other lawful action, the directors may fix, in advance, a record date, which
shall not be more than sixty days nor less than ten days before the date of such
meeting, nor more than sixty days prior to any other action.  For the purpose of
determining the stockholders entitled to express consent to corporate action in
writing without a meeting, the directors may fix a record date, which shall not
precede the date upon which the resolution fixing the record date is adopted by
the board of directors, and which shall not be more than 10 days after the date
upon which the resolution fixing the record date is adopted by the board of
directors.  If no record date is fixed, the record date for determining
stockholders entitled to notice of or to vote at a meeting of stockholders shall
be at the close of business on the day next preceding the day on which notice is
given, or, if notice is waived, at the close of business on the day next
preceding the day on which the meeting is held; the record date for determining
stockholders entitled to express consent to corporate action in writing without
a meeting, when no prior action by the Board of Directors is necessary, shall be
the day on which the first written consent is expressed; and the record date for
determining stockholders for any other purpose shall be at the close of business
on the day on which the Board of Directors adopts the resolution relating
thereto.  A determination of stockholders of record entitled to notice of or to
vote at any meeting of stockholders shall apply to any adjournment of the
meeting; provided, however, that the Board of Directors may fix a new record
date for the adjourned meeting.

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          5.   MEANING OF CERTAIN TERMS.  As used herein in respect of the right
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to notice of a meeting of stockholders or a waiver thereof or to participate or
vote thereat or to consent or dissent in writing in lieu of a meeting, as the
case may be, the term "share" or "shares" or "share of stock" or "shares of
stock" or "stockholder" or "stockholders" refers to an outstanding share or
shares of stock and to a holder or holders of record of outstanding shares of
stock when the corporation is authorized to issue only one class of shares of
stock, and said reference is also intended to include any outstanding share or
shares of stock and any holder or holders of record of outstanding shares of
stock of any class upon which or upon whom the certificate of incorporation
confers such rights where there are two or more classes or series of shares of
stock or upon which or upon whom the General Corporation Law confers such right
notwithstanding that the certificate of incorporation may provide for more than
one class or series of shares of stock, one or more of which are limited or
denied such rights thereunder; provided, however, that no such right shall vest
in the event of an increase or a decrease in the authorized number of shares of
stock of any class or series which is otherwise denied voting rights under the
provisions of the certificate of incorporation.

          6.   STOCKHOLDER MEETINGS.
               -------------------- 

          - TIME.  The annual meeting shall be held on the date and at the time
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fixed, from time to time, by the directors, provided, that the first annual
meeting shall be held on a date within thirteen months after the organization of
the corporation, and each successive annual meeting shall be held on a date
within thirteen months after the date of the preceding annual meeting.  A
special meeting shall be held on the date and at the time fixed by the
directors.

          - PLACE.  Annual meetings and special meetings shall be held at such
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place, within or without the State of Delaware, as the directors may, from time
to time fix.  Whenever the directors shall fail to fix such place, the meeting
shall be held at the registered office of the corporation in the State of
Delaware.

          - CALL.  Annual meetings and special meetings may be called by the
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directors or by any officer instructed by the directors to call the meeting.

          - NOTICE OR WAIVER OF NOTICE.  Written notice of all meetings shall be
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given, stating the place, date and hour of the meeting and stating the place
within the city or other municipality or community at which the list of
stockholders of the corporation may be examined.  The notice of an annual
meeting shall state that the meeting is called for the election of directors and
for the transaction of other business which may properly come before the
meeting, and shall, (if any other action which could be taken at a special
meeting is to be taken at such annual meeting) state the purpose or purposes.
The notice of a special meeting shall in all instances state the purpose or
purposes for which the meeting is called.  The notice of any meeting shall also
include, or be accompanied by, any additional statements, information, or
documents prescribed by the General Corporation Law.  Except as otherwise
provided by the General Corporation Law, a copy of the notice of any meeting
shall be given, personally or by mail, not less than ten days nor more than
sixty days before the date of the meeting, unless the 

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lapse of the prescribed period of time shall have been waived, and directed to
each stockholder at his record address or at such other address which he may
have furnished by request in writing to the Secretary of the corporation. Notice
by mail shall be deemed to be given when deposited, with postage thereon
prepaid, in the United States mail. If a meeting is adjourned to another time,
not more than thirty days hence, and/or to another place, and if an announcement
of the adjourned time and/or place is made at the meeting, it shall not be
necessary to give notice of the adjourned meeting unless the directors, after
adjournment, fix a new record date for the adjourned meeting. Notice need not be
given to any stockholder who submits a written waiver of notice signed by him
before or after the time stated therein. Attendance of a stockholder at a
meeting of stockholders shall constitute a waiver of notice of such meeting,
except when the stockholder attends the meeting for the express purpose of
objecting, at the beginning of the meeting, to the transaction of any business
because the meeting is not lawfully called or convened. Neither the business to
be transacted at, nor the purpose of, any regular or special meeting of the
stockholders need be specified in any written waiver of notice.

          - STOCKHOLDER LIST.  The officer who has charge of the stock ledger of
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the corporation shall prepare and make, at least ten days before every meeting
of stockholders, a complete list of the stockholders, arranged in alphabetical
order, and showing the address of each stockholder and the number of shares
registered in the name of each stockholder.  Such list shall be open to the
examination of any stockholder, for any purpose germane to the meeting, during
ordinary business hours, for a period of at least ten days prior to the meeting,
either at a place within the city or other municipality or community where the
meeting is to be held, which place shall be specified in the notice of the
meeting, or if not so specified, at the place where the meeting is to be held.
The list shall also be produced and kept at the time and place of the meeting
during the whole time thereof, and may be inspected by any stockholder who is
present. The stock ledger shall be the only evidence as to who are the
stockholders entitled to examine the stock ledger, the list required by this
section or the books of the corporation, or to vote at any meeting of
stockholders.

          - CONDUCT OF MEETING.  Meetings of the stockholders shall be presided
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over by one of the following officers in the order of seniority and if present
and acting - the Chairman of the Board, if any, the Vice-Chairman of the Board,
if any, the President, a Vice-President, or, if none of the foregoing is in
office and present and acting, by a chairman to be chosen by the stockholders.
The Secretary of the corporation, or in his absence, an Assistant Secretary,
shall act as secretary of every meeting, but if neither the Secretary nor an
Assistant Secretary is present the Chairman of the meeting shall appoint a
secretary of the meeting.

          - PROXY REPRESENTATION.  Every stockholder may authorize another
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person or persons to act for him by proxy in all matters in which a stockholder
is entitled to participate, whether by waiving notice of any meeting, voting or
participating at a meeting, or expressing consent or dissent without a meeting.
Every proxy must be signed by the stockholder or by his attorney-in-fact.  No
proxy shall be voted or acted upon after three years from its date unless such
proxy provides for a longer period.  A duly executed proxy shall be irrevocable
if it states that it is irrevocable and, if, and only as long as, it is coupled
with an interest sufficient in 

                                      -4-

 
law to support an irrevocable power. A proxy may be made irrevocable regardless
of whether the interest with which it is coupled is an interest in the stock
itself or an interest in the corporation generally.

          - INSPECTORS.  The directors, in advance of any meeting, may, but need
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not, appoint one or more inspectors of election to act at the meeting or any
adjournment thereof.  If an inspector or inspectors are not appointed, the
person presiding at the meeting may, but need not, appoint one or more
inspectors.  In case any person who may be appointed as an inspector fails to
appear or act, the vacancy may be filled by appointment made by the directors in
advance of the meeting or at the meeting by the person presiding thereat.  Each
inspector, if any, before entering upon the discharge of his duties, shall take
and sign an oath faithfully to execute the duties of inspector at such meeting
with strict impartiality and according to the best of his ability. The
inspectors, if any, shall determine the number of shares of stock outstanding
and the voting power of each, the shares of stock represented at the meeting,
the existence of a quorum, the validity and effect of proxies, and shall receive
votes, ballots or consents, hear and determine all challenges and questions
arising in connection with the right to vote, count and tabulate all votes,
ballots or consents, determine the result, and do such acts as are proper to
conduct the election or vote with fairness to all stockholders.  On request of
the person presiding at the meeting, the inspector or inspectors, if any, shall
make a report in writing of any challenge, question or matter determined by him
or them and execute a certificate of any fact found by him or them.

          - QUORUM.  The holders of a majority of the outstanding shares of
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stock shall constitute a quorum at a meeting of stockholders for the transaction
of any business.  The stockholders present may adjourn the meeting despite the
absence of a quorum.

          - VOTING.  Each share of stock shall entitle the holder thereof to one
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vote.  In the election of directors, a plurality of the votes cast shall elect.
Any other action shall be authorized by a majority of the votes cast except
where the General Corporation Law prescribes a different percentage of votes
and/or a different exercise of voting power, and except as may be otherwise
prescribed by the provisions of the certificate of incorporation and these By-
Laws.  In the election of directors, and for any other action, voting need not
be by ballot.

          7.   STOCKHOLDER ACTION WITHOUT MEETINGS.  Any action required by the
               -----------------------------------                             
General Corporation Law to be taken at any annual or special meeting of
stockholders, or any action which may be taken at any annual or special meetings
of stockholders, may be taken without a meeting, without prior notice and
without a vote, if a consent in writing, setting forth the action so taken,
shall be signed by the holders of outstanding stock having not less than the
minimum number of votes that would be necessary to authorize or take such action
at a meeting at which all shares entitled to vote thereon were present and
voted. Prompt notice of the taking of the corporate action without a meeting by
less than unanimous written consent shall be given to those stockholders who
have not consented in writing.

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                                  ARTICLE II
                                  ----------

                                   DIRECTORS
                                   ---------

          1.   FUNCTIONS AND DEFINITION.  The business and affairs of the
               ------------------------                                  
corporation shall be managed by or under the direction of the Board of Directors
of the corporation.  The Board of Directors shall have the authority to fix the
compensation of the members thereof.  The use of the phrase "whole board" herein
refers to the total number of directors which the corporation would have if
there were no vacancies.

          2.   QUALIFICATIONS AND NUMBER.  A director need not be a stockholder,
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a citizen of the United States, or a resident of the State of Delaware.  The
property, affairs and business of the corporation shall be managed by its Board
of Directors.  The number of directors may be fixed from time to time by action
of the stockholders or of the directors and may be increased or decreased by
action of the stockholders or of the directors.

          3.   ELECTION AND TERM.  The first Board of Directors, unless the
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members thereof shall have been named in the certificate of incorporation, shall
be elected by the incorporator or incorporators and shall hold office until the
first annual meeting of stockholders and until their successors are elected and
qualified or until their earlier resignation or removal. Any director may resign
at any time upon written notice to the corporation.  Thereafter, directors who
are elected at an annual meeting of stockholders, and directors who are elected
in the interim to fill vacancies and newly created directorships, shall hold
office until the next annual meeting of stockholders and until their successors
are elected and qualified or until their earlier resignation or removal.  In the
interim between annual meetings of stockholders or of special meetings of
stockholders called for the election of directors and/or for the removal of one
or more directors and for the filling of any vacancy in that connection, newly
created directorships and any vacancies in the Board of Directors, including
vacancies resulting from the removal of directors for cause or without cause,
may be filled by the vote of a majority of the remaining directors then in
office, although less than a quorum, or by the sole remaining director.

          4.   MEETINGS.
               -------- 

          - TIME.  Meetings shall be held at such time as the Board shall fix,
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except that the first meeting of a newly elected Board shall be held as soon
after its election as the directors may conveniently assemble.

          - PLACE.  Meetings shall be held at such place within or without the
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State of Delaware as shall be fixed by the Board.

          - CALL.  No call shall be required for regular meetings for which the
            ----                                                               
time and place have been fixed.  Special meetings may be called by or at the
direction of the Chairman of the Board, if any, the Vice-Chairman of the Board,
if any, of the President, or of a majority of the directors in office.

                                      -6-

 
          - NOTICE OR ACTUAL OR CONSTRUCTIVE WAIVER.  No notice shall be
            ---------------------------------------                     
required for regular meetings for which the time and place have been fixed.
Written, oral, or any other mode of notice of the time and place shall be given
for special meetings in sufficient time for the convenient assembly of the
directors thereat.  Notice need not be given to any director or to any member of
a committee of directors who submits a written waiver of notice signed by him
before or after the time stated therein.  Attendance of any such person at a
meeting shall constitute a waiver of notice of such meeting, except when he
attends a meeting for the express purpose of objecting, at the beginning of the
meeting, to the transaction of any business because the meeting is not lawfully
called or convened.  Neither the business to be transacted at, nor the purpose
of, any regular or special meeting of the directors need be specified in any
written waiver of notice.

          - QUORUM AND ACTION.  A majority of the whole Board shall constitute a
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quorum except when a vacancy or vacancies prevents such majority, whereupon a
majority of the directors in office shall constitute a quorum, provided, that
such majority shall constitute at least one-third of the whole Board.  A
majority of the directors present, whether or not a quorum is present, may
adjourn a meeting to another time and place.  Except as herein otherwise
provided, and except as otherwise provided by the General Corporation Law, the
vote of the majority of the directors present at a meeting at which a quorum is
present shall be the act of the Board.  The quorum and voting provisions herein
stated shall not be construed as conflicting with any provisions of the General
Corporation Law and these By-Laws which govern a meeting of directors held to
fill vacancies and newly created directorships in the Board or action of
disinterested directors.

          Any member or members of the Board of Directors or of any committee
designated by the Board, may participate in a meeting of the Board, or any such
committee, as the case may be, by means of conference telephone or similar
communications equipment by means of which all persons participating in the
meeting can hear each other.

          - CHAIRMAN OF THE MEETING.  The Chairman of the Board, if any and if
            -----------------------                                           
present and acting, shall preside at all meetings.  Otherwise, the Vice-Chairman
of the Board, if any and if present and acting, or the President, if present and
acting, or any other director chosen by the Board, shall preside.

          5.   REMOVAL OF DIRECTORS.  Except as may otherwise be provided by the
               --------------------                                             
General Corporation Law, any director or the entire Board of Directors may be
removed, with or without cause, by the holders of a majority of the shares then
entitled to vote at an election of directors.

          6.   COMMITTEES.  Whenever its number consists of three or more, the
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Board of Directors may, by resolution passed by a majority of the whole Board,
designate one or more committees, each committee to consist of two or more of
the directors of the corporation. The Board may designate one or more directors
as alternate members of any committee, who may replace any absent or
disqualified member at any meeting of the committee.  In the absence or
disqualification of any member of any such committee or committees, the member
or 

                                      -7-

 
members thereof present at any meeting and not disqualified from voting, whether
or not he or they constitute a quorum, may unanimously appoint another member of
the Board of Directors to act at the meeting in the place of any such absent or
disqualified member. Any such committee, to the extent provided in the
resolution of the Board, shall have and may exercise the powers and authority of
the Board of Directors in the management of the business and affairs of the
corporation with the exception of any authority the delegation of which is
prohibited by Section 14l of the General Corporation Law, and may authorize the
seal of the corporation to be affixed to all papers which may require it.

          7.   WRITTEN ACTION.  Any action required or permitted to be taken at
               --------------                                                  
any meeting of the Board of Directors or any committee thereof may be taken
without a meeting, without prior notice and without a vote if all members of the
Board or committee, as the case may be, consent thereto in writing, and the
writing or writings are filed with the minutes of proceedings of the Board or
committee.


                                  ARTICLE III
                                  -----------

                                   OFFICERS
                                   --------

          The officers of the corporation shall consist of a President, a
Secretary, a Treasurer, and, if deemed necessary, expedient, or desirable by the
Board of Directors, a Chairman of the Board, a Vice-Chairman of the Board, an
Executive Vice-President, one or more other Vice-Presidents, one or more
Assistant Secretaries, one or more Assistant Treasurers, and such other officers
with such titles as the resolution of the Board of Directors choosing them shall
designate.  Except as may otherwise be provided in the resolution of the Board
of Directors choosing him, no officer other than the Chairman or Vice-Chairman
of the Board, if any, need be a director.  Any number of officers may be held by
the same person, as the directors may determine, except that no person may hold
the offices of President and Secretary simultaneously.

          Unless otherwise provided in the resolution choosing him, each officer
shall be chosen for a term which shall continue until the meeting of the Board
of Directors following the next annual meeting of stockholders and until his
successor shall have been chosen and qualified.

          All officers of the corporation shall have such authority and perform
such duties in the management and operation of the corporation as shall be
prescribed in the resolutions of the Board of Directors designating and choosing
such officers and prescribing their authority and duties, and shall have such
additional authority and duties as are incident to their office except to the
extent that such resolutions may be inconsistent therewith.  The Secretary or an
Assistant Secretary of the corporation shall record all of the proceedings of
all meetings and actions in writing of stockholders, directors, and committees
of directors, and shall exercise such additional authority and perform such
additional duties as the Board shall assign to him.  Any officer may 

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be removed, with or without cause, by the Board of Directors. Any vacancy in any
office may be filled by the Board of Directors.


                                  ARTICLE IV
                                  ----------

                                CORPORATE SEAL
                                --------------

          The corporate seal shall be in such form as the Board of Directors
shall prescribe.


                                   ARTICLE V
                                   ---------

                                  FISCAL YEAR
                                  -----------

          The fiscal year of the corporation shall be fixed, and shall be
subject to change, by the Board of Directors.


                                  ARTICLE VI
                                  ----------

                             CONTROL OVER BY-LAWS
                             --------------------

          Subject to the provisions of the certificate of incorporation and the
provisions of the General Corporation Law, the power to amend, alter or repeal
these By-Laws and to adopt new By-Laws may be exercised by the Board of
Directors or by the stockholders.



          I HEREBY CERTIFY that the foregoing is a full, true and correct copy
of the By-Laws of Locomotion Therapy, Inc., a Delaware corporation, as in effect
on the date hereof.

          IN WITNESS WHEREOF, I set my hand this 14th day of July, 1997.
 
                             /s/ Sheila Snukal
                             -------------------------------------              
                             Secretary of Locomotion Therapy, Inc.

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