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                                                                    EXHIBIT 10.6


                                                                [EXECUTION COPY]

                   AMENDED AND RESTATED SUBSIDIARIES GUARANTEE

         This AMENDED AND RESTATED SUBSIDIARIES GUARANTEE dated as of September
30, 1999, among the subsidiaries of Northstar Health Services, Inc. (the
"Company") set forth on Schedule I hereto (as the successors to the Guarantors
(as such term is defined in the Original Guarantee (as defined below)), each, a
"Guarantor", and collectively, the "Guarantors"), CERBERUS CAPITAL MANAGEMENT,
LLC (the "Agent") and THE CHASE MANHATTAN BANK, as Collateral Agent as provided
for in Section 8.1B of the Credit Agreement referred to below (as successor
collateral agent to IBJ WHITEHALL BANK & TRUST COMPANY, formerly known as IBJ
SCHRODER BANK & TRUST COMPANY, the "Collateral Agent"), amends and restates in
its entirety that certain Subsidiaries Guarantee, dated as of October 20, 1995
(as amended, modified or supplemented prior to the date hereof, the "Original
Guarantee"), among the Guarantors and IBJ Schroder Bank & Trust Company (the
"Original Agent").

                                    RECITALS

         A. The Company, the Original Agent and the lenders set forth on the
signature pages thereto are parties to that certain Credit Agreement, dated as
of October 20, 1995 (as amended, modified or supplemented prior to the date
hereof, the "Original Credit Agreement"), pursuant to which the Lenders agreed
to extend certain credit facilities to the Company (the "Original Loans") which
were represented by certain promissory notes (the "Original Notes"), the
proceeds of which were used (i) to refinance substantially all indebtedness of
the Company and the Guarantors outstanding on the date thereof, (ii) to pay
certain fees and expenses, (iii) to provide financing for the working capital
needs of the Company and the Guarantors and (iv) to provide a portion of the
purchase price of certain acquisitions by the Company and the Guarantors.

         B. The Original Agent now wishes to resign as agent for the Lenders and
the Agent wishes to replace the Original Agent as agent for the Lenders.

         C. The Company, the Guarantors, the Lenders, the Agent and the
Collateral Agent (together with the Agent, the "Agents") have agreed to amend
and restate the Original Credit Agreement as of the date hereof (the Original
Credit Agreement, as so amended and restated being referred to herein as the
"Credit Agreement") to (i) extend the maturity of the Original Loans on the
terms set forth therein, (ii) reflect the Original Agent's resignation as agent
for the Lenders thereunder and the appointment of the Agent as successor agent
for the Lenders, and (iii) make certain other changes as more fully set forth
therein.

         D. The Guarantors and the Agents now wish to amend and restate the
Original Guarantee in its entirety to (i) provide for the continuation of the
guarantee of the Obligations by the Guarantors and (ii) reflect the Original
Agent's resignation as agent for the Lenders and the appointment of the Agent as
its successor as agent for the Lenders.

         E. The Company owns, directly or indirectly, all of the issued and
outstanding capital stock of the Guarantors.

         F. The Company and the Guarantors are engaged in related businesses,
and each of the Guarantors will derive substantial direct and indirect benefit
from the continuation of the Loans pursuant to the Credit Agreement.

         G. It is the intent of the Company, the Guarantors, the Lenders, the
Agent and


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the Collateral Agent that the amendment and restatement of the Original Credit
Agreement shall not constitute a novation of the obligations and liabilities of
the parties under the Original Credit Agreement nor be deemed to evidence or
constitute repayment of all or any portion of such obligations and liabilities
and that the Credit Agreement shall amend and restate in its entirety the
Obligations under the Original Credit Agreement and re-evidence the Obligations
of the Company outstanding thereunder.

         H. Each of the Guarantors hereby represents and confirms, and the
Agents acknowledge, that (i) the guarantee of the Obligations pursuant to the
Original Guarantee continues in full force and effect and continues as a valid
and enforceable guarantee of the Obligations under the Credit Agreement, (ii)
the Loans represented by the Notes are the same Original Loans which were, prior
to the date hereof, represented by the Original Notes, and (iii) the
transactions contemplated by the Credit Agreement and this Agreement did not and
do not constitute a discharge or release of the guarantee under the Original
Guarantee and that the guarantee of the Obligations continues as a valid
guarantee of the Loans and the Obligations.

         I. It is a condition precedent to the obligation of the Lenders to
amend and restate the Original Credit Agreement and to extend the maturity of
the Original Loans that the Guarantors execute this Agreement and continue to
guarantee the Obligations.

                                    AGREEMENT

         In consideration of the premises and the mutual covenants and the
mutual agreements herein set forth, the parties agree as follows:


                                    ARTICLE I

                                   Definitions

         Section 1.01. Certain Defined Terms. Capitalized terms used but not
defined herein have the meanings given to them in the Credit Agreement.

                                   ARTICLE II

                                   Guarantee

         Section 2.01. Unconditional Guarantee. The Guarantors, jointly and
severally, hereby unconditionally guarantee to the Agent and the Collateral
Agent for their benefit and the ratable benefit of the Lenders the due and
punctual payment of the Obligations when and as the Obligations shall become
due, whether at maturity, by acceleration or otherwise. The obligations of the
Guarantors under this Agreement constitute an absolute, unconditional, present
and continuing irrevocable guaranty of payment and not of collectibility. If the
Company shall fail to pay any amount of the Obligations when due the Guarantors
shall immediately pay the amount to the Agent for its benefit, the benefit of
the Collateral Agent and the ratable benefit of the Lenders.

         Section 2.02. No Defenses.

         (a) Laws. Each Guarantor guarantees that the Obligations will be paid
to the Agents and the Lenders strictly in accordance with the terms of the Loan
Documents regardless of any law, statute, regulation, rule, writ, judgment,
order, decree or award now or hereafter in effect which might in any way affect
any of those terms or the rights


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of the Agents or the Lenders against the Company or the Guarantors, or which
might cause or permit to be invoked any alteration of the time, amount or manner
of payment by the Company or the Guarantors under those terms.

         (b) No Other Defenses. To the full extent permitted by law, the
obligations of the Guarantors under this Guarantee shall not be subject to any
counterclaim, set-off, deduction, diminution, abatement, recoupment, suspension,
deferment, reduction or defense (other than the full and strict compliance by
the Guarantors with those obligations) based on any claim that any Guarantor or
any other Person may have against the Company, the Agents, any Lender or any
other Person.

         (c) Guarantee Unaffected. The obligations of the Guarantors under this
Agreement shall be absolute and unconditional, present and continuing and shall
remain in full force and effect and shall not be released, discharged or in any
way affected by any circumstance or condition of any nature (whether or not any
Guarantor, the Company, the Agents or any Lender shall have any notice or
knowledge of the circumstance or condition), including, without limitation:

                  (i) the invalidity, illegality, unenforceability, discharge,
         termination, cancellation or frustration, in whole or in part, of any
         Obligation, Loan Document or other document;

                  (ii) the exercise or failure to exercise or enforce by any
         Person any right, remedy, privilege or power under any Loan Document or
         other document;

                  (iii) any demand or attempt to collect from, or failure to
         demand or attempt to collect from, the Company, Guarantor or any other
         Person under any Loan Document or other document;

                  (iv) the giving, acceptance, existence, non-existence,
         validity, invalidity or value of any security or collateral, including,
         without limitation, the Collateral and the Pledged Collateral, securing
         the Obligations or any guarantee of the Obligations or any attempt or
         failure to attempt to realize upon that security, collateral or
         guarantee;

                  (v) the exchange, substitution, renewal, extension,
         modification, compromise, release, discharge or failure to perfect for
         any reason any security, collateral or Guarantee, including, without
         limitation, the guarantee under this Agreement;

                  (vi) any change in the time, place or manner of payment or the
         waiver, consent, extension, renewal, indulgence, compromise, release,
         settlement, refunding, funding, or any other forbearance or other
         action taken, delayed or omitted by the Agents, any Lender, the
         Company, any Guarantor or any other Person under or in respect of any
         term or provision of any Obligation, Loan Document or other document;

                  (vii) the termination, modification, alteration, amendment,
         waiver, addition, deletion or other change to any Obligation, Loan
         Document or other document or any provision of any of those documents;

                  (viii) the liquidation, dissolution, merger or consolidation
         of the Company, any Guarantor or any other Person, or the transfer by
         the Company, any Guarantor or any other Person of all or any part of
         its property or assets;

                  (ix) the voluntary or involuntary bankruptcy, receivership,
         liquidation, insolvency, reorganization, arrangement, assignment for
         the benefit of creditors


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         or similar proceedings involving or affecting the Company, any
         Guarantor or any other Person or any of their property;

                  (x) the change in the ownership of any shares of capital stock
         of the Company or any Guarantor or the change in or termination of the
         corporate relationship between the Company and any Guarantor, as the
         case may be;

                  (xi) the release or discharge, by operation of law or
         otherwise, of the Company, any Guarantor or any other Person from any
         Obligation or any provision of any Loan Document or other document; and

                  (xii) any other circumstance whatsoever, foreseen or
         unforseen, which may or might in any manner or to any extent vary the
         risks of any Guarantor or might otherwise constitute a defense
         available to or a legal or equitable discharge of a surety or a
         guarantor or limit recourse against any Guarantor or otherwise.

IT IS THE PURPOSE AND INTENT OF THIS GUARANTY AGREEMENT THAT THE OBLIGATIONS OF
THE GUARANTORS UNDER THIS AGREEMENT ARE ABSOLUTE AND UNCONDITIONAL, PRESENT AND
CONTINUING UNDER ANY AND ALL CIRCUMSTANCES.

         Section 2.03. Right of Set-off. Upon the occurrence and during the
continuation of an Event of Default, the Agents and the Lenders are hereby
irrevocably authorized at any time and from time to time without notice to, or
the consent of, any Guarantor, any such notice being hereby waived by the
Guarantors, to set off and appropriate and apply any and all deposits (general
or special, time or demand, provisional or final, but excluding trust deposits),
in any currency, and any other credits, indebtedness or claims, in any currency,
in each case whether direct or indirect, absolute or contingent, matured or
unmatured, at any time held or owing by the Agents or any Lender to or for the
credit or the account of such Guarantor, or any part thereof in such amounts as
the Agents or any Lender may elect, on account of the liabilities of such
Guarantor hereunder and claims of every nature and description of the Agents or
any Lender against such Guarantor, in any currency, whether arising hereunder,
under the Loan Documents, the Notes or otherwise, as the Agents or any Lender
may elect, whether or not the Agents or any Lender has made any demand for
payment and although such liabilities and claims may be contingent or unmatured.
The Agents or such Lenders shall notify such Guarantor promptly of any such
set-off and the application made by the Agents or such Lenders, provided that
the failure to give such notice shall not affect the validity of such set-off
and application. The rights of the Agents or any Lender under this paragraph are
in addition to other rights and remedies, including, without limitation, other
rights of set-off, which the Agents or such Lenders may have.


                                   ARTICLE III

                         Representations and Warranties

          Each of the Guarantors hereby represents and warrants to the Agents
and the Lenders as follows:

         Section 3.01. Power. Such Guarantor has good right and all necessary
power and authority to execute and deliver this Agreement and to consummate the
transactions contemplated hereby, including, without limitation, the guarantee
of the Obligations.

         Section 3.02. Authorization; Binding Effect. The execution and delivery
by such Guarantor of this Agreement, the performance by such Guarantor of its
obligations


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under this Agreement and the consummation of the transactions contemplated
hereby has been duly authorized by all necessary corporate or partnership
action, as the case may be. No other proceedings on the part of such Guarantor
are necessary to approve and adopt this Agreement or to approve the consummation
of the transactions contemplated hereby. This Agreement has been duly executed
and delivered by such Guarantor and is a legal, valid and binding obligation of
such Guarantor enforceable against such Guarantor in accordance with its terms.

         Section 3.03. Contravention. Neither the execution, delivery and
performance of this Agreement by such Guarantor nor the consummation of the
transactions contemplated hereby will (with or without notice or lapse of time
or both) (a) conflict with, violate or breach any provision of such Guarantor's
organizational documents or bylaws, (b) violate, conflict with or result in a
breach of any Regulation, writ, judgment, injunction, order, decree or award of
any Governmental Body or any other Person by which such Guarantor or any of its
properties may be bound or affected, (c) conflict with, result in a default
under, or give rise to a right of termination, cancellation, or acceleration or
to a loss of a benefit under any material contract or agreement to which such
Guarantor is a party or by which such Guarantor or any of its properties may be
bound or affected or (d) result in or require the creation or imposition of any
Lien on any property now owned or hereafter acquired by such Guarantor.

         Section 3.04. Approvals. No authorization, consent, order or approval
of, notice to or registration or filing with, or any other action by any
Governmental Body or other Person, is required or advisable in connection with
(a) the due execution and delivery by such Guarantor of this Agreement, (b) the
consummation of the transactions contemplated by this Agreement, (c) the
performance by such Guarantor of its obligations under this Agreement, or (d)
the exercise by the Agents or any Lender of their rights and remedies under this
Agreement.

         Section 3.05. Credit Agreement Representations and Warranties. Each of
the representations and warranties set forth in the Credit Agreement is true and
correct insofar as the same relate to such Guarantor, and such representations
and warranties are hereby incorporated by reference as if set forth in full
herein. Such Guarantor agrees that such representations and warranties shall be
deemed to have been made by such Guarantor on the date of each borrowing by the
Company under the Credit Agreement on and as of the date of borrowing as though
made hereunder on and as of such date.

                                   ARTICLE IV

                                   Covenants

         Section 4.01. Credit Agreement Covenants. Each of the Guarantors
covenants and agrees that it will perform or comply with each of the covenants
and agreements contained in the Credit Agreement to the extent such covenants
relate to such Guarantor, and such covenants and agreements are hereby
incorporated by reference as if set forth in full herein.

                                    ARTICLE V

                      Termination, Waivers and Subrogation

         Section 5.01. Continuing Guaranty. This Agreement shall continue to be
effective and shall remain in full force and effect until the Obligations shall
be paid and otherwise performed in full. For the purposes of this Agreement, the
Obligations shall not be deemed to have been paid and performed in full until
the holders or owners of the Obligations shall have indefeasibly received
payment of the Obligations in full in cash. Thereafter, this Agreement shall be
reinstated if at any time any payment of any


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of the Obligations is rescinded or must otherwise be returned upon the
insolvency, bankruptcy or reorganization of the Company or any other person or
otherwise, all as though the payment had not been made.

         Section 5.02. Waivers by the Guarantors. Each of the Guarantors
unconditionally waives, to the full extent permitted by law:

                  (a) Set-Off. Any defense, set-off or counterclaim which such
         Guarantor may otherwise assert against the Agents, the Lenders or any
         other Person.

                  (b) Notice, etc. Presentment, protest, demand for payment,
         promptness, diligence, notice of protest, notice of any other action at
         any time taken or omitted by the Agents, any Lender or any other Person
         and, generally, all demands and notices of every kind in connection
         with any Loan Document or the Obligations, including, without
         limitation:

                           (i) notice of any of the matters referred to in
                  Section 2.02(c); and

                           (ii) all notices which may be required by statute,
                  rule of law or otherwise, now or hereafter in effect, to
                  preserve intact any rights against the Company or such
                  Guarantor under any Loan Document or as a requirement to the
                  enforcement, assertion or exercise against the Company of any
                  right, power, privilege or remedy conferred under any Loan
                  Document.

                  (c) Exhaust Other Remedies. Any requirement to exhaust any
         rights or remedies or to mitigate the damages resulting from any
         default under any Loan Document or any other document or any
         requirement to protect, secure, perfect or insure any Lien or any
         property subject to the Lien or take any other action against any
         person or any collateral or other property.

                  (d) Claims. All claims that the sale price of any Collateral
         was inadequate or unreasonable for any reason and all other claims to
         damages and demands of any nature against the Agents and the Lenders.

                  (e) Equitable Rights. All equities and rights of appraisal,
         stay and redemption (whether now or hereafter existing), in each case
         arising out of the Agents or the Lenders enforcing any of their rights
         and remedies under any Loan Document.

                  (f) Other Circumstances. Any other circumstance whatsoever,
         including, without limitation, those stated in Section 2.02(c), which
         might otherwise constitute a defense to or a legal or equitable
         discharge or release of a guarantor or surety or a party granting
         security or which might otherwise limit recourse against such
         Guarantor.

         Section 5.03. Subrogation; Subordination.

         (a) Subrogation. No Guarantor shall be subrogated, in whole or in part,
to the rights of the Agents or any Lender against the Company under any Loan
Document until the payment in full of the Obligations.

         (b) Subordination. Any claim of any Guarantor against the Company
arising from payments made by such Guarantor under this Agreement shall be in
all respects subordinate to the payment and performance in full and discharge of
the Obligations.

         (c) No Claims. No payment under this Agreement by any Guarantor shall
give rise to any claim of such Guarantor against the Agents, the Lenders or any
other holder of the Obligations.

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         (d) No Assignment of Claims. Unless and until all Obligations shall
have been paid and performed in full, no Guarantor will assign or otherwise
transfer any claim against the Company to any other person.

         (e) Postponement of Rights. Each Guarantor agrees that any rights it
may have against any other guarantor of any of the Obligations for
contributions, exoneration from payment or otherwise, in respect of any amounts
paid by such Guarantor under this Agreement or which may continue to be owing
under this Agreement, shall be postponed until, and such Guarantor agrees not to
seek to enforce any such right until, the Obligations are paid and performed in
full.

         Section 5.04. Effect of Bankruptcy Proceedings. If an event permitting
the acceleration of any of the Obligations shall at any time have occurred and
be continuing, and the acceleration shall at such time be prevented by reason of
the pendency against the Company of a case or proceeding under a bankruptcy or
insolvency law, each Guarantor agrees that, for purposes of this Agreement and
each Guarantor's obligations under this Agreement, the Obligations shall be
deemed to have been accelerated with the same effect as if they had been
accelerated in accordance with the terms of the Loan Documents. In such an event
each Guarantor shall immediately pay the full amount of the Obligations due and
owing by reason of the acceleration, without further notice or demand.

                                   ARTICLE VI

                                  Miscellaneous

         Section 6.01. Notices. Unless otherwise specifically provided herein,
any notice or other communication herein required or permitted to be given shall
be in writing and may be personally served, telexed or sent by telefacsimile (so
long as such notice sent by telefacsimile is followed within two Business Days
by a notice sent by another method specified hereunder) or United States mail or
courier service and shall be deemed to have been given when delivered in person
or by courier service, upon receipt of telefacsimile or telex, or three Business
Days after depositing it in the United States mail with postage prepaid and
properly addressed; provided that notices to Agent shall not be effective until
received. For the purposes hereof, the address of each party hereto shall be as
set forth under such party's name on the signature pages hereof or (i) as to
Company, the Collateral Agent and Agent, such other address as shall be
designated by such Person in a written notice delivered to the other parties
hereto and (ii) as to each other party, such other address as shall be
designated by such party in a written notice delivered to Agent.

         Section 6.02. Expenses. Each Guarantor agrees to pay any and all
expenses, including, without limitation, all fees and disbursements of counsel,
which may be paid or incurred by the Agents or any Lender in enforcing, or
obtaining advice of counsel in respect of, any rights with respect to, or
collecting, any or all of the Obligations and/or enforcing any rights with
respect to, or collecting against, such Guarantor under this Guarantee.

         Section 6.03. Transfer of Notes. If any Lender shall transfer any Note
held by it or grant participations in all or any of its Obligations, the
transferees of the Note or the grantees of the participations, as the case may
be, shall have the rights of the Lender under this Agreement in respect of the
Note or Obligations.

         Section 6.04. Counterparts. This Agreement may be executed
simultaneously in one or more counterparts, and by different parties hereto in
separate counterparts,


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each of which when executed will be deemed an original, but all of which taken
together will constitute one and the same instrument.

         Section 6.05. Interpretation. As used in this Agreement, references to
the singular will include the plural and vice versa and references to the
masculine gender will include the feminine and neuter genders and vice versa, as
appropriate. Unless otherwise expressly provided in this Agreement (a) the words
"hereof", "herein" and "hereunder" and words of similar import when used in this
Agreement will refer to this Agreement as a whole and not to any particular
provision of this Agreement and (b) article, section, subsection, schedule and
exhibit references are references with respect to this Agreement unless
otherwise specified. References in this Agreement to any law or regulation will
refer to such laws and regulations as from time to time amended and to any laws
or regulations successor thereto. Unless the context otherwise requires, the
term "including" will mean "including, without limitation".

         Section 6.06. Descriptive Headings. The headings in this Agreement and
in the Schedules, Exhibits and Annexes are included for convenience of reference
only and will not affect in any way the meaning or interpretation of this
Agreement.

         Section 6.07. Incorporation of Schedules, Exhibits and Annexes. The
Schedules, Exhibits and Annexes hereto are incorporated into this Agreement and
will be deemed a part hereof as if set forth herein in full. In the event of any
conflict between the provisions of this Agreement and any Schedule, Exhibit or
Annex, the provisions of this Agreement will control.

         Section 6.08. Amendment of Agreement. This Agreement may not be amended
except by an instrument in writing signed on behalf of each of the parties
hereto.

         Section 6.09. Successors and Assigns. This Agreement will be binding
upon and inures to the benefit of and is enforceable by the respective
successors and permitted assigns of the parties hereto. This Agreement may not
be assigned by any party hereto without the prior written consent of all other
parties hereto. Any assignment or attempted assignment in contravention of this
Section will be void ab initio and will not relieve the assigning party of any
obligation under this Agreement.

         Section 6.10. No Waiver; Remedies. No failure or delay by any party in
exercising any right, power or privilege under this Agreement will operate as a
waiver of the right, power or privilege. A single or partial exercise of any
right, power or privilege will not preclude any other or further exercise of the
right, power or privilege or the exercise of any other right, power or
privilege. The rights and remedies provided in this Agreement and the other Loan
Documents will be cumulative and not exclusive of any rights or remedies
provided by law.

         Section 6.11. Severability. If any term or other provision of this
Agreement is invalid, illegal or incapable of being enforced by any rule of law,
or public policy, all other conditions and provisions of this Agreement will
nevertheless remain in full force and effect so long as the economic or legal
substance of the transactions contemplated hereby is not affected in any manner
adverse to any party. Upon such determination that any term or other provision
is invalid, illegal or incapable of being enforced, the parties hereto will
negotiate in good faith to modify this Agreement so as to effect the original
intent of the parties as closely as possible in an acceptable manner to the end
that the transactions contemplated hereby are fulfilled to the extent possible.

         Section 6.12. Governing Law. This Agreement will be governed by, and
construed in accordance with, the laws of the state of New York applicable to
contracts executed in and to be performed entirely within that state.


<PAGE>   9


         Section 6.13. No Third-Party Rights. This Agreement is not intended,
and will not be construed, to create any rights in any parties other than the
Guarantors, the Agents and the Lenders, and no Person may assert any rights as
third-party beneficiary hereunder.

         Section 6.14. Submission to Jurisdiction. Any Action with respect to
this Agreement may be brought in the courts of the State of New York or of the
United States of America for the Southern District of New York, and each of the
Guarantors, the Agents and the Lenders hereby accepts for itself and in respect
of its property, generally and unconditionally, the jurisdiction of these
courts. Each of the Guarantors, the Agents and the Lenders hereby irrevocably
waives any objection, including, without limitation, any objection to the laying
of venue or based on the grounds of forum non conveniens, which it may now or
hereafter have to the bringing of any Action in those jurisdictions.

         Section 6.15. Waiver of Jury Trial. Each party waives any right to a
trial by jury in any Action to enforce or defend any right under this Agreement
or any amendment, instrument, document or agreement delivered or to be delivered
in connection with this Agreement and agrees that any Action will be tried
before a court and not before a jury.

         IN WITNESS WHEREOF, the parties have executed and delivered this
Agreement as of the date first written above in New York, New York.

AGENT:
                                             CERBERUS CAPITAL MANAGEMENT, LLC,
Address:                                        as Agent for the Lenders
450 Park Avenue
New York, New York  10022
Attention:  Joyce Johnson-Miller
Telephone:  (212) 891-2119
Facsimile:  (212) 750-5212                   By:________________________________
                                                Name:
                                                Title:


COLLATERAL AGENT:
                                             THE CHASE MANHATTAN BANK, as
Address:                                        Collateral Agent for the Lenders
450 West 33rd Street
14th Floor
New York, New York  10001
Attention:  Capital Markets Fiduciary
            Services, Cerberus Capital
Telephone:  (212) 946-3200
Facsimile:  (212) 946-8302                   By:________________________________
                                                Name:
                                                Title:





<PAGE>   10


SUBSIDIARY GUARANTORS:

Address:                                     NSHS SERVICES, INC.
c/o Northstar Health Services, Inc.
The Atrium
665 Philadelphia Street
P.O. Box 1289
Indiana, Pennsylvania  15701
Attention:  Thomas W. Zavcha
Telephone:  (724) 465-3200
Facsimile:  (724) 465-3726                   By:________________________________
                                                Name:
                                                Title:


Address:                                     KEYSTONE REHABILITATION
                                                SYSTEMS, INC.
c/o Northstar Health Services, Inc.
The Atrium
665 Philadelphia Street
P.O. Box 1289
Indiana, Pennsylvania  15701
Attention:  Thomas W. Zavcha
Telephone:  (724) 465-3200
Facsimile:  (724) 465-3726                   By:________________________________
                                                Name:
                                                Title:


Address:                                     KEYSTONE REHABILITATION
                                                MANAGEMENT, INC.
c/o Northstar Health Services, Inc.
The Atrium
665 Philadelphia Street
P.O. Box 1289
Indiana, Pennsylvania  15701
Attention:  Thomas W. Zavcha
Telephone:  (724) 465-3200
Facsimile:  (724) 465-3726                   By:________________________________
                                                Name:
                                                Title:


<PAGE>   11




Address:                                     NORTHSTAR MEDICAL SERVICES, INC.
c/o Northstar Health Services, Inc.
The Atrium
665 Philadelphia Street
P.O. Box 1289
Indiana, Pennsylvania  15701
Attention:  Thomas W. Zavcha
Telephone:  (724) 465-3200
Facsimile:  (724) 465-3726                   By:________________________________
                                                Name:
                                                Title:


Address:                                     NORTHSTAR DIAGNOSTIC SERVICES, INC.
c/o Northstar Health Services, Inc.
The Atrium
665 Philadelphia Street
P.O. Box 1289
Indiana, Pennsylvania  15701
Attention:  Thomas W. Zavcha
Telephone:  (724) 465-3200
Facsimile:  (724) 465-3726                   By:________________________________
                                                Name:
                                                Title:


Address:                                     VASCUSONICS, INC.
c/o Northstar Health Services, Inc.
The Atrium
665 Philadelphia Street
P.O. Box 1289
Indiana, Pennsylvania  15701
Attention:  Thomas W. Zavcha
Telephone:  (724) 465-3200
Facsimile:  (724) 465-3726                   By:________________________________
                                                Name:
                                                Title:



<PAGE>   12

                                                                      SCHEDULE I
                                                                              to
                                     AMENDED AND RESTATED SUBSIDIARIES GUARANTEE

                                   Guarantors

         NSHS Services, Inc.
         Keystone Rehabilitation Systems, Inc.
         Keystone Rehabilitation Management Inc.
         Northstar Medical Services, Inc.
         Northstar Diagnostic Services, Inc.
         Vascusonics Inc.