EXHIBIT 10.51 FIRST AMENDMENT TO COST SHARING AGREEMENT ----------------------------------------- THIS FIRST AMENDMENT is made as of the 1st day of April, 2001, by and among SELECT TRANSPORT, INC., a Delaware corporation ("ST"), having an address at...

                                                                   EXHIBIT 10.51

                   FIRST AMENDMENT TO COST SHARING AGREEMENT
                   -----------------------------------------


          THIS FIRST AMENDMENT is made as of the 1st day of April, 2001, by and
among SELECT TRANSPORT, INC., a Delaware corporation ("ST"), having an address
at 0000 Xxx Xxxxxxxxxx Xxxx, Xxxxxxxxxxxxx, Xxxxxxxxxxxx 00000, SELECT MEDICAL
CORPORATION, a Delaware corporation ("SMC"), having an address at 0000 Xxx
Xxxxxxxxxx Xxxx, X.X. Xxx 0000, Xxxxxxxxxxxxx, Xxxxxxxxxxxx 00000, and SELECT
AIR II CORPORATION, a Pennsylvania corporation ("SAII"), having an address at
0000 Xxx Xxxxxxxxxx Xxxx, Xxxxxxxxxxxxx, Xxxxxxxxxxxx 00000.


                                  BACKGROUND
                                  ----------

     A.   ST, SMC and SAII executed and delivered that certain Cost Sharing
Agreement dated December 11, 2000 (the "Agreement"), pursuant to which the
parties agreed to share certain costs relating to the operation of a hanger and
aircraft located at Harrisburg International Airport.  All capitalized terms not
specifically defined herein shall have the meanings ascribed to them in the
Agreement.

     B.   ST, SMC and SAII now desire to amend the Agreement as hereinafter
provided.

     NOW, THEREFORE, the parties hereto, intending to be legally bound hereby,
covenant and agree as follows:

     1.   Amendment to Section 2. The percentage "40%" which is set forth in the
          ----------------------
second sentence of Section 2 of the Agreement is hereby changed to "25%".

     2.   No Other Modifications. Except as expressly amended hereby, the
          ----------------------
Agreement shall remain unmodified and in full force and effect.


     IN WITNESS WHEREOF, the parties hereto have caused this First Amendment to
be executed the day and year first above written.


                              SELECT TRANSPORT, INC., a Delaware corporation


                              By: Xxxxxxx X. Xxxxxxx
                                 --------------------------
                                   Xxxxxxx X. Xxxxxxx
                                   Treasurer


                              SELECT MEDICAL CORPORATION., a Delaware
                              corporation


                              By: Xxxxxxx X. Xxxxxx
                                 --------------------------
                                   Xxxxxxx X. Xxxxxx
                                   Senior Vice President


                              SELECT AIR II CORPORATION, a Pennsylvania
                              corporation


                              By: Xxxxxxx X. Xxxxxxx
                                 --------------------------
                                   Xxxxxxx X. Xxxxxxx
                                   Vice President


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