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                                                                   Exhibit 10.58

                       ASSIGNMENT AND ASSUMPTION AGREEMENT

         This ASSIGNMENT AND ASSUMPTION AGREEMENT (this "AGREEMENT"), dated as
of November 20, 2001, is by and among DONJOY, L.L.C., a Delaware limited
liability company, as assignor (the "ASSIGNOR"), DJ ORTHOPEDICS, INC., a
Delaware corporation, as assignee (the "ASSIGNEE"), FIRST UNION NATIONAL BANK,
as administrative agent (in such capacity, the "ADMINISTRATIVE AGENT") and as
collateral agent (in such capacity, the "COLLATERAL AGENT"), and THE CHASE
MANHATTAN BANK, as syndication agent (in such capacity, the "SYNDICATION AGENT")
under that certain Credit Agreement dated as of June 30, 1999 among the
Assignor, dj Orthopedics, L.L.C., a Delaware limited liability company (the
"BORROWER"), the Administrative Agent, the Syndication Agent, and the Lenders
party thereto (as amended by Amendment No. 1 dated as of May 25, 2000, and
Agreement dated as of July 13, 2000, and as such may be amended, supplemented or
otherwise modified from time to time, the "CREDIT AGREEMENT"). Capitalized terms
used herein without definition shall have the meanings ascribed to such terms in
the Credit Agreement.

                              BACKGROUND STATEMENT

         The Borrower is a wholly owned subsidiary of the Assignor. Pursuant to
the Credit Agreement, the Lenders have extended credit to the Borrower, and have
agreed to further extend credit to the Borrower, pursuant to the terms and
conditions set forth therein.

         The Assignee intends to consummate a registered public offering of its
common stock (the "IPO") immediately following the completion of (i) the merger
of DJ Acquisition Corporation, a Delaware corporation and a wholly owned
subsidiary of the Assignee (the "MERGER SUB"), with and into the Assignor,
pursuant to which the Assignor will be the surviving entity and will become a
wholly owned subsidiary of the Assignee, and (ii) the merger of the Assignor
with and into the Assignee (the "SECOND MERGER"), pursuant to which the Assignee
will be the surviving entity and will become the owner of 100% of the
outstanding membership interests in the Borrower.

         As a condition to the consummation of the transactions described in the
preceding paragraph, the Assignor has agreed to assign to the Assignee, and the
Assignee has agreed to assume from the Assignor, all of the rights, interests,
duties, obligations and liabilities of the Assignor in, to and under the Credit
Agreement and the other Loan Documents.

                             STATEMENT OF AGREEMENT

                  ACCORDINGLY, in consideration of the premises and the mutual
agreements contained herein and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
hereby agree as follows:

         SECTION 1. ASSIGNMENT AND ASSUMPTION. Effective immediately prior to
the effective time of the Second Merger, (a) the Assignor hereby assigns,
transfers and conveys to the

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Assignee all of the rights, interests, duties, obligations and liabilities of
the Assignor in, to and under the Credit Agreement, the Security Agreement, the
Pledge Agreement, the Parent Guarantee Agreement and all other Loan Documents to
which the Assignor is a party, and (b) the Assignee hereby assumes and accepts
all of the rights, interests, duties, obligations and liabilities of the
Assignor in, to and under such Loan Documents and becomes a party thereto, all
to the same extent as if the Assignee had originally executed such Loan
Documents in the place and stead of the Assignor. The Assignee confirms that,
after giving effect to this Agreement and the Second Merger, the Loan Documents
to which the Assignee is becoming a party pursuant to this Agreement shall
remain in full force and effect, shall be enforceable against the Assignee in
accordance with their respective terms, and shall not be discharged, diminished,
limited or otherwise affected in any respect, and that the Liens and security
interests granted thereunder in favor of the Collateral Agent for the benefit of
the Secured Parties shall continue to be validly existing and perfected Liens
and security interests (to the extent perfected immediately before giving effect
to this Agreement, and subject to Section 9-508(b) of the Uniform Commercial
Code), superior and prior to the rights of all other Persons therein except for
Permitted Encumbrances.

         SECTION 2. REPRESENTATIONS OF ASSIGNEE. The Assignee hereby represents
and warrants that, as of the date hereof and after giving effect to this
Agreement, each of the representations and warranties set forth in Article III
of the Credit Agreement is true and correct in all material respects with the
same effect as if made on the date hereof, except to the extent such
representations and warranties expressly relate to an earlier date (in which
case such representations and warranties shall be true and correct in all
material respects as to such earlier date).

         SECTION 3. NOTICES TO ASSIGNEE. The address of the Assignee for
purposes of all notices and other communications under the Credit Agreement and
the other Loan Documents is as set forth for in Section 9.01(a) of the Credit
Agreement.

         SECTION 4. APPLICABLE LAW. THIS AGREEMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

         SECTION 5. EFFECT OF AGREEMENT. Except as expressly set forth herein,
this Agreement shall not, by implication or otherwise, limit, impair, constitute
a waiver of, or otherwise affect the rights and remedies of the Lenders, the
Administrative Agent, the Syndication Agent, the Borrower or the Assignee under
the Credit Agreement or any other Loan Document, and shall not alter, modify,
amend or in any way affect any of the terms, conditions, obligations, covenants
or agreements contained in the Credit Agreement or any other Loan Document, all
of which are ratified and affirmed in all respects and shall continue in full
force and effect. After the date hereof, any reference to the Credit Agreement
shall mean the Credit Agreement as modified hereby. This Agreement shall
constitute a "Loan Document" for all purposes of the Credit Agreement and the
other Loan Documents. This Agreement may not be amended nor may any provision
hereof be waived except pursuant to a writing signed by each of the parties
hereto.

         SECTION 6. COUNTERPARTS. This Agreement may be executed by one or more
of the parties to this Agreement on any number of separate counterparts
(including by facsimile transmission),


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and all of said counterparts taken together shall be deemed to constitute one
and the same instrument.

         SECTION 7. HEADINGS. The headings used herein are for convenience of
reference only, are not part of this Agreement and are not to be taken into
consideration in interpreting this Agreement.

                         (SIGNATURES ON FOLLOWING PAGE)




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         IN WITNESS WHEREOF, the parties have duly executed this Agreement as of
the day and year first above written.

                                  DONJOY, L.L.C.


                                  By:    /s/ Leslie H. Cross
                                         -------------------
                                         Name:  Leslie H.  Cross
                                         Title: President and Chief Executive
                                                Officer


                                  DJ ORTHOPEDICS, INC.


                                  By:    /s/ Cyril Talbot III
                                         --------------------
                                         Name:  Cyril Talbot III
                                         Title: Vice President - Finance,
                                                Chief Financial Officer &
                                                Secretary


                                  FIRST UNION NATIONAL BANK, as
                                  Administrative Agent and Collateral Agent


                                  By:    /s/ Douglas T. Davis
                                         --------------------
                                         Name:  Douglas T. Davis
                                         Title: Senior Vice President



                                  THE CHASE MANHATTAN BANK, as
                                  Syndication Agent


                                  By:    /s/ ROBERT BOTTAMENDI
                                         ---------------------
                                         Name:  Robert Bottamendi
                                         Title: Vice President



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