Brief Answer:
Please adhere to the given guidelines

Detailed Answer:
Dear XXXX
Welcome to HCM
We understand your concerns

On the day of surgery. Patients are given a set of exercises to start immediately in the recovery room. I hope the those exercises were advised and your brother started them. Hopefully your brother left crutches and he is able to walk independently. typically it takes seven to 10 days after the procedure.

The first two weeks after surgery concentrates on decreasing the swelling in the knee and regaining knee extension, with less concern about knee flexion. This is accomplished by elevating/icing the leg and riding the stationary bike.

Two weeks after surgery, the goal is for patients to achieve and maintain full knee extension and increase quadriceps muscle function. While knee flexion of only 90 degrees is the goal for this stage, obtaining full extension is more of a priority.

Regarding rehabilitation, Although different surgeons and therapists will have slightly different protocols, the goal for all forms of post-operative ACL rehabilitation is the same: to return the patient to a normal and complete level of function in as short a time possible without compromising the integrity of the surgically reconstructed knee.

In order to achieve this goal, therapy is typically broken down into stages (or phases) of activity, with goals for each stage. Here is an example of a standard five-phase protocol:

Phase I - First two weeks after surgery - Emphasis:

Control of inflammation
Range of motion - full extension, and 90 degrees of knee flexion
Achievement of quadriceps control
Education of patient about rehabilitation process
Crutches - usually seven to 10 days until patient is comfortable
Patellar Mobilization - to prevent patellar tendon shortening/contracture and loss of knee motion

Phase II - two to six weeks after surgery - Emphasis:

Strengthening - light weights and sports cords
Full range of motion (Walking and stretching)
Continued protection of the graft from stresses
Improvement of endurance and proprioception - use of treadmill, step machine and elliptical trainer

Phase III - six weeks to three to four months after surgery - Emphasis:

Improve patient's confidence in the knee
Progression in strength, power, and proprioception - preparing for return to sport
Jogging typically allowed at three months
Straight ahead running

Phase IV - four to six months after surgery -Emphasis:

Possible return to sport, depending on type of sporting activity and type of graft
Full pain free range of motion should be present
Sufficient strength and proprioception should be present
Typically, patient is advanced to initiate advanced lifting exercises
Phase is typically customized to the patient's activity level and competition level in sport.

Phase V - return to sport, usually at six months - Emphasis:

Patient must meet all the criteria for return to sports
No soft tissue or range of motion complaints
Physician must clear the patient to resume full activities
The goal is safe return to sports
Education of patient about possible limitations
Maintenance of strength, endurance, and proprioception
Functional bracing may be recommended by some physicians for the first one to two years after surgery for psychological confidence.

The phases given here are examples. But the pattern is almost same. You can choose the exercise according to the guide lines given.

Still better shall be to find a qualified physiotherapist and request advice. The above guidelines may be followed.

Hope this answers your query.
Available for further clarifications.
Good luck.

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