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                                                                    Exhibit 10.4

           THIS SUBORDINATED NOTE HAS NOT BEEN REGISTERED UNDER THE
         SECURITIES ACT OF 1933, AS AMENDED, OR ANY APPLICABLE STATE
                SECURITIES LAW, AND MAY NOT BE SOLD, ASSIGNED,
                PLEDGED, HYPOTHECATED OR OTHERWISE DISPOSED OF
                 EXCEPT IN COMPLIANCE WITH APPLICABLE FEDERAL
                   AND STATE SECURITIES LAWS AND THE OTHER
                  RESTRICTIONS ON TRANSFER SET FORTH HEREIN.


                         SUBORDINATED PROMISSORY NOTE

$2,800,000                                               Plainsboro, New Jersey
                                                            January 14, 2000

     FOR VALUE RECEIVED, INTEGRA LIFESCIENCES CORPORATION, a Delaware
corporation ("Maker") having offices at 311-C Enterprise Drive, Plainsboro,
New Jersey 08536, promises to pay to the order of CLINICAL NEURO SYSTEMS
HOLDINGS LLC, a Delaware limited liability company ("Payee"), in lawful money
of the United States of America, at the offices of Payee at 311-C Enterprise
Drive, Plainsboro, New Jersey 08536, the principal sum of TWO MILLION EIGHT
HUNDRED THOUSAND DOLLARS ($2,800,000), together with interest at the rate or
rates and in the installments and at the times hereinafter provided.

     1. Interest Rate. All sums outstanding from time to time hereunder shall
bear interest until the date paid at the rate of five percent (5%) per annum,
such interest to be paid as provided in Section 2 below.

     2. Principal and Interest Payments.

        (a) The principal of and all accrued interest on this Subordinated Note
shall be paid in two installments due and payable on January 15, 2001 and
January 14, 2002. Each installment will be equal to the sum of (i) One
Million Four Hundred Thousand Dollars ($1,400,000) of principal plus (ii) all
accrued and unpaid interest on the outstanding principal balance of this
Subordinated Note at the rate set forth in Section 1 above. Each such
installment shall first be applied to the payment of interest on the
outstanding principal of this Subordinated Note, and the remainder thereof
shall be applied on account of such principal.

        (b) Both before and after any default, interest shall be calculated on
the basis of a 365-day year and the actual days elapsed.

     3. Prepayments. Maker may not at any time prepay the principal of this
Subordinated Note in whole or in part.

     4. Penalties. If any installment of principal or interest or both
hereunder is not paid within ten (10) days after becoming due, Maker shall
pay to Payee on demand interest at the annual rate of fifteen percent (15%)
of such overdue amount for the number of days such

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payment is overdue. The amount of any such penalties not paid promptly
following demand shall be deemed outstanding and payable pursuant to this
Subordinated Note.

     5. Events of Default. Each of the following shall constitute an event of
default (each, an "Event of Default") hereunder:

        (a) If any proceeding under the Bankruptcy Code or any law of the United
States of America or of any state relating to insolvency, receivership, or debt
adjustment is instituted by Maker, or if any such proceeding is instituted
against Maker and is consented to by the respondent or an order for relief shall
be entered in such proceeding or such proceeding shall remain undismissed for
sixty (60) days, or if Maker becomes a debtor under the Bankruptcy Code of the
United States of America, or a trustee or receiver is appointed for any
substantial part of its property, or if Maker makes an assignment for the
benefit of creditors; or

        (b) There occurs an event of default under that certain Secured
Promissory Note, dated the date hereof, issued by Payee to Clinical Neuro
Systems, Inc.

     6. Remedies. If an Event of Default occurs hereunder, at the option of
Payee, the entire principal balance, late fees, penalties and all accrued but
unpaid interest hereunder shall become immediately due and payable, and Payee
may thereupon exercise any rights or remedies provided for in this
Subordinated Note or otherwise available at law or in equity.

     7. Subordination. Notwithstanding any other provision of this
Subordinated Note to the contrary:

     7.1 The payment and performance of the principal, interest and expense
reimbursement obligations evidenced by this Subordinated Note (collectively,
the "Subordinated Debt") are subordinated to the Senior Obligations (as
hereinafter defined) and, except for Permitted Payments (as hereinafter
defined), the Payee will have no right to ask, demand, sue for, take or
receive from the Maker, by setoff or in any other manner of the whole or any
part of the Subordinated Debt which may now or hereafter be owing by the
Maker, no right to enforce any claim with respect to the Subordinated Debt,
or otherwise to take any action against the Maker or Maker's property, unless
and until all such Senior Obligations, whether now existing or hereafter
arising, and whether such Senior Obligations arise after the Maker or the
Maker's estate becomes the subject of proceedings under the Bankruptcy Code
or whether such Senior Obligations are acquired outright, conditionally or as
collateral security from another by any existing or future holder of Senior
Obligations, shall have been fully paid and satisfied with interest,
including interest on any loans or advances made to the Maker after the Maker
or the Maker's estate becomes the subject of proceedings under Title 11 of
the United States Code, 11 U.S.C. ss. 101 et seq. or any replacement or
supplemental federal statute dealing with the bankruptcy of debtors (the
"Bankruptcy Code") and all commitments under the documents evidencing any of
the Senior Obligations have expired or been terminated.


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     7.2. As used in this Section 7:

          "Credit Accommodation" means (a) any bond issued or guaranteed by,
     or any loan or advance now or hereafter made to or guaranteed by, the
     Maker, including any financing or extension of credit provided to the
     Maker pursuant to Section 363 or 364 of the Bankruptcy Code, (b) any
     bankers acceptance or letter of credit now or hereafter issued by or for
     the account of the Maker or as to which the Maker has guaranteed
     repayment or reimbursement, (c) any overdraft now or hereafter permitted
     to occur in any deposit account of the Maker, (d) any forward foreign
     exchange contract, interest rate or currency swap or other derivative
     now or hereafter issued to or for the benefit of the Maker or as to
     which the Maker has guaranteed payment, and (e) any securitization
     facility or structured financing with respect to the Maker's receivables
     and/or other financial assets now or hereafter arising.

          "Permitted Payments" shall mean all regularly scheduled payments of
     principal and interest of the Subordinated Debt that are made prior to
     written notice to Payee of a matured event of default (specifying
     whether such default is a payment default or other default) under the
     documents and instruments now or hereafter governing any of the Senior
     Obligations (as such documents may be amended, restated, replaced and/or
     otherwise modified from time to time in the sole discretion of the Maker
     and any existing or future holder of any Senior Obligations, regardless
     of whether the Payee receives notice of any such amendment, restatement,
     replacement and/or other modification or of the incurrence of any Senior
     Obligations) or after the cure of such matured event of default,
     provided that regularly scheduled payments of principal and interest on
     the Subordinated Debt may resume nine months after written notice of any
     event of default which is not a payment default.

          "Senior Obligations" shall mean any and all obligations of the
     Maker (whether for principal, interest accruing before or after the
     commencement of a case under the Bankruptcy Code whether or not such
     interest is permitted to be paid by the Maker, premium, fees,
     indemnities, expense reimbursements, costs of collection and enforcement
     or preservation and protection of collateral or otherwise) which may now
     or at any time hereafter be owing by the Maker in respect of any Credit
     Accommodation as to which the material transaction document(s) signed by
     the Maker specifically state(s) that such Credit Accommodation is
     intended to constitute a Senior Obligation pursuant to the terms of this
     Section 7; provided, however, that in no event will the aggregate
     principal amount of Senior Obligations at any one time outstanding
     exceed $10,000,000, plus interest and fees in respect thereof and
     reasonable costs of collection and enforcement thereof.

     7.3. In the event of any distribution, division, or application, partial
or complete, voluntary or involuntary, by operation of law or otherwise, of
all or any part of the assets of the Maker or the proceeds thereof to the
creditors of the Maker or readjustment of the Senior Obligations and
Subordinated Debt, whether by reason of liquidation, bankruptcy, arrangement,

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receivership, assignment for the benefit of creditors or any other action or
proceeding involving the readjustment of all or any part of the Senior
Obligations or the Subordinated Debt, or the application of the assets of the
Maker to the payment or liquidation thereof, or upon the dissolution or other
winding up of the Maker's business, or upon the sale of all or substantially
all of the Maker's assets, then, and in any such event, (i) the holder(s) of
the Senior Obligations shall be entitled to receive payment in full of any
and all of the Senior Obligations then owing prior to the payment of all or
any part of the Subordinated Debt, and (ii) any payment or distribution of
any kind or character, whether in cash, securities or other property, which
shall be payable or deliverable upon or with respect to any or all of the
Subordinated Debt shall be paid or delivered directly to the holder(s) of the
Senior Obligations for application on any of the Senior Obligations, due or
not due, until such Senior Obligations shall have first been fully paid and
satisfied.

     7.4. Except for Permitted Payments, should any payment or distribution
or security or instrument or proceeds thereof be received by the Payee upon
or with respect to the Subordinated Debt prior to the satisfaction of all of
the Senior Obligations, the Payee shall be required to receive and hold the
same in trust, as trustee, for the benefit of the holder(s) of the Senior
Obligations, and shall forthwith deliver the same to such holder(s), in
precisely the form received (except for the endorsement or assignment of the
Payee where necessary), for application on any of the Senior Obligations, due
or not due, and, until so delivered, the same shall be held in trust by the
Payee as the property of the holder(s) of the Senior Obligations.

     7.5. The provision of this Section 7 shall be effective and may not be
terminated or otherwise revoked until the Senior Obligations shall have been
fully discharged and all commitments to extend additional Senior Obligations
have been terminated. In the event the Payee shall have any right under
applicable law or otherwise to terminate or revoke the provisions of this
Section 7 which right cannot be waived, such termination or revocation shall
not be effective until written notice of such termination or revocation,
signed by the Payee, is actually received by the holder(s) of the Senior
Obligations. In the absence of the circumstances described in the immediately
preceding sentence, this is a continuing agreement of subordination and
existing and future holder(s) of Senior Obligations may commence and/or
continue, at any time and without notice to the Payee, to extend credit or
other financial accommodations and loan monies to or for the benefit of the
Maker on the faith hereof. Any termination or revocation described
hereinabove shall not affect the provisions of this Section 7 in relation to
(a) any of the Senior Obligations which arose prior to receipt thereof, (b)
any of the Senior Obligations which represent interest on Senior Obligations,
or (c) any of the Senior Obligations created after receipt thereof, if such
Obligations were incurred either through extensions of credit by the
holder(s) of Senior Obligations pursuant to financing arrangements with the
Maker in an aggregate principal amount at any one time outstanding amount not
to exceed $10,000,000, and/or for the purpose of preserving or protecting any
collateral (including, but not limited to, all protective advances, costs,
expenses) and/or for attorneys' and paralegals' fees, whensoever made,
advanced or incurred by any holder of Senior Obligations in connection with
the Senior Obligations.

     7.6. IN ACCEPTING THIS SUBORDINATED NOTE, THE PAYEE EXPRESSLY WAIVES ALL
NOTICE OF THE ACCEPTANCE BY ANY EXISTING OR FUTURE HOLDER OF SENIOR
OBLIGATIONS OF THE SUBORDINATION AND OTHER PROVISIONS OF THIS SECTION 7 AND
ALL OTHER NOTICES NOT

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SPECIFICALLY REQUIRED PURSUANT TO THE TERMS OF THIS SECTION 7 WHATSOEVER, AND
THE PAYEE EXPRESSLY WAIVES RELIANCE BY ANY SUCH HOLDER OF SENIOR OBLIGATIONS
UPON THE SUBORDINATION AND OTHER AGREEMENTS AS HEREIN PROVIDED.

     7.7. If the Maker or the Maker's estate becomes the subject of
proceedings under the Bankruptcy Code and if any existing or future holder of
Senior Obligations desires to permit the use of cash collateral or to provide
financing to the Maker under either Section 363 or Section 364 of the
Bankruptcy Code, by accepting this Subordinated Note, the Payee agrees that
adequate notice of such financing to the Payee shall have been provided if
the Payee received notice two (2) business days prior to the entry of any
order approving such cash collateral usage or financing. All allocations of
payments between the holder(s) of the Senior Obligations and the Payee shall,
subject to any court order, continue to be made after the filing of a
petition under the Bankruptcy Code on the same basis that the payments were
to be allocated prior to the date of such filing. By accepting this
Subordinated Note, the Payee agrees: (a) in the event that the Payee has or
at any time acquires any security for the Subordinated Debt, not to assert
any right it may have to "adequate protection" of its interest in such
security in any bankruptcy proceeding and not to seek to have the automatic
stay lifted with respect to such security, without the prior written consent
of each holder of Senior Obligations, and (b) the Payee waives any claim or
defense the Payee may now or hereafter have arising out of the election by
any holder of Senior Obligations, in any proceeding instituted under Chapter
11 of the Bankruptcy Code, of the application of Section 1111(b)(2) of the
Bankruptcy Code, and/or any borrowing or grant of a security interest under
Section 364 of the Bankruptcy Code by the Maker, as debtor-in-possession. To
the extent that any holder of Senior Obligations receives payments on, or
proceeds of collateral for, the Senior Obligations which are subsequently
invalidated, declared to be fraudulent or preferential, set aside and/or
required to be repaid to a trustee, receiver or any other party under any
bankruptcy law, state or federal law, common law, or equitable cause, then,
to the extent of such payment or proceeds received, the Senior Obligations,
or part thereof, intended to be satisfied shall be revived and continue in
full force and effect as if such payments or proceeds had not been received
by such holder of Senior Obligations.

     7.8 Nothing in this Section 7 or elsewhere in this Subordinated Note is
intended to or shall impair, as between the Maker, its creditors other than
the holders of the Senior Obligations, and the holders of this Subordinated
Note, the obligation of the Maker, which is absolute and unconditional, to
pay to the holders of this Subordinated Note the principal interest on this
Subordinated Note as and when the same shall become due and payable in
accordance with its terms, or is intended to or shall affect the relative
rights of the holders of this Subordinated Note and the creditors of the
Maker other than the holders of the Senior Obligations.

     8. Consent by Maker. Maker and the endorsers hereof and sureties
therefor, if any, and all others who may be liable for all or any part of the
indebtedness evidenced by this Subordinated Note, consent to any number of
renewals or extensions of the time of payment hereof without notice to any of
those parties. The granting, without notice, of any extension of time for the
payment of any sum due under this Subordinated Note or for the performance at
any covenant, condition or agreement hereof, shall in no way release or
discharge the liability of Maker or of any such endorsers or sureties.

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     9. Notices. All notices required to be given to any of the parties
hereunder shall be in writing and shall be deemed to have been sufficiently
given for all purposes when presented personally to such party or sent by
certified or registered mail, return receipt requested, or by courier service
with guaranteed next business day delivery, addressed to such party at its
address provided herein. Such notice shall be deemed to be given when
received if delivered personally, or three (3) business days after the date
deposited with the U. S. Postal Service if sent by certified or registered
mail, return receipt requested, or one (1) business day after the same is
delivered to a courier service with guaranteed next business day delivery.
Any notice of any change in such address shall also be given in the manner
set forth above.

     10. Captions. The captions or headings of the Sections in this
Subordinated Note are for convenience only and shall not control or affect
the meaning or construction of any of the terms or provisions of this
Subordinated Note.

     11. Governing Law; Amendment. This Subordinated Note shall be governed
by and construed in accordance with the laws of the Commonwealth of
Pennsylvania. This Subordinated Note may only be amended by an instrument in
writing signed by both Maker and Payee.

     12. Assignment. This Subordinated Note is not assignable without the
prior written consent of the Maker, which consent may be withheld in Maker's
sole and absolute discretion. This Subordinated Note shall be binding upon
the respective legal representatives, successors and permitted assigns of the
parties hereto.

     IN WITNESS WHEREOF, each party hereto, intending to be legally bound
hereby, has caused this Subordinated Note to be executed by its duly
authorized officers, the date and year first above written.

                                      INTEGRA LIFESCIENCES CORPORATION


                                      By:
                                          -------------------------------------
                                            Stuart M. Essig
                                            Chief Executive Officer



ACCEPTED AND AGREED:

CLINICAL NEURO SYSTEMS HOLDINGS LLC

By:  Integra LifeSciences Corporation, its sole member


By:
    -----------------------------------
       Stuart M. Essig
       Chief Executive Officer



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