ACL Rehabilitation

Knee Rehabilitation after ACL Surgery

It is impossible to develop a “cookbook” method for how to rehabilitate a patient after ACL repair or reconstruction. The protocol should be patient specific with progress based on the patient achieving specific criteria as well consideration of the normal biology for acl graft healing.
ACL rehabilitation consists of distinct phases. It is possible to overlap phases depending on the individual progress of the patient. It is also possible to move backward if a patient struggles with a particular phase.

Phase I: Pre-Operative

With this protocol, patients presenting with an ACL deficient knee may be seen in physical therapy, with an athletic or personal trainer prior to ACL surgery.

Pre-Op Goals:

  1. Restore full ROM and strength and control swelling
  2. Ensure complete understanding of the basic principles of rehabilitation including:
  3. Full terminal knee extension
  4. Early weight bearing – if there isn’t a meniscus tear otherwise non-weight bearing
  5. Closed and open chain strengthening


  1. Bilateral ROM including full terminal knee extension
  2. Single leg hop on non-involved leg for baseline measurements


  1. Prone hangs – regaining full knee extension is most important
  2. Extension board – initiate early if difficulty achieving full extension
  3. Heel slides
  4. Core – It is important to maintain core strength (include hip abduction strength)
  5. Closed kinetic chain strengthening – Use e-stim, quad sets and straight leg raises

Phase IIA: Control Pain & Swelling

1 to 14 Days After ACL Surgery

Clinical Goals:

  1. Full passive knee extension and 110 degrees of flexion (90 degrees if mensicus repaired)
  2. Independent straight leg raise- electrical stimulation at 60 degrees knee flexion
  3. Weight bearing as tolerated unless meniscus repair, then non-weightbearing for 2 weeks
  4. Reduce swelling- cryotherapy and e-stim


  1. Bilateral ROM


  1. Ice is placed on the patient’s knee immediately after surgery. This provides compression and cold to minimize pain and swelling. The ice also remains on the knee at all times 1st week, except when performing motion exercises.

  2. Ankle pumps starting day of surgery for DVT prevention

  3. Knee Extension – exercises hourly during the day:

    1. Elevate the heel on pillows at the foot of the bed. A 2.5 lb. Ankle weight is placed across the proximal tibia to facilitate terminal extension. Full extension allows the newly reconstructed ligament to fit perfectly into the intercondylar notch. Restricting full extension will allow the notch to fill with scar and become a block to extension.
    2. The knee is allowed to fully extend to terminal extension for ten minutes during each exercise bout.
  4. Knee Flexion

    • Heel slides with towel
    • Wall slides when able
  5. Leg Control

    • Active quadriceps contraction with quad sets
    • Quad e-stim for biofeedback
    • Straight leg raises

During the first week, the patient is to remain lying down as much as possible. However, when getting up to go to the bathroom, the patient is encouraged to be full weight bearing as tolerated with the crutches or walker and knee immobilizer.

Clinical Follow-Up

Patient will report to physical therapy 3-5 days after surgery.

Phase IIB: Early Mobilization

Progress once goals for Phase IIA have been attained- usually 2-6 weeks

Clinical Goals:

  1. Minimal swelling and soft tissue healing – continue cryotherapy

  2. Full weight bearing in brace at this time if meniscus was repaired

  3. Other patients can unlock brace for normal gait without assist devices

  4. Demonstrate ability to lock knee with weight shifted to ACL leg

  5. Strengthen core


  1. Measure prone heel height difference

  2. Supine knee flexion compared to contralateral knee

  3. Thigh circumference 10 & 15cm above patella


  1. Maintaining full extension range of motion is CRITICAL

  2. Patient is encouraged to lock out knee by standing with weight shifted to ACL leg so that extension is full and knee is fully locked (single leg stance).

  3. Knee flexion

    1. Wall slides, heel slides
    2. Progress to full flexion by 6 weeks without meniscus repair and 8 weeks with repair
  4. Stationary bike workouts are started. Initially, the bike is used as a mechanical means of attaining flexion. Once the patient has gained 120 degrees of flexion, they can use the bike for moderate speed strengthening workouts.

  5. Gait training

    1. Progress from partial to full weight bearing without crutches. It is very important to emphasize leg control early in the rehabilitation program. Through early extension and normal gait, the patient is able to regain good quadriceps tone and leg control.
  6. Closed and open kinetic strengthening– Once the patient has regained full knee extension and is ambulating normally, it will be possible to implement strengthening exercises:

    1. Wall squats, Leg presses, Calf raises
  7. Swimming and other hydrotherapy exercises can be started once the incisions have healed.

  8. Core

Prone planks

Side planks


Bridge with leg raise

Hip strengthening:

Single leg squat-progress to no hand support

Wall Squats

Isometric engagement of gluteal muscles

Add bands


Hip Strengthening with Bands:

Side to side walk

45 degree forward walk

45 degree backwards walk

Clinical Follow-Up

Patient will follow-up with surgeon 3 weeks after surgery with full extension, full weight bearing with brace, active quad contraction, ability to perform straight leg raise and 1+ or less swelling.

** If full terminal extension is not regained by 3-4 weeks then an extension board must be implemented and the surgeon notified**

Phase III: Static Conditioning

Usually by 6-8 Weeks After ACL Surgery but must be based on attaining all goals for Phase II

Clinical Goals:

  1. Full flexion to 135 degrees

  2. Consistent weight room and moderate speed strengthening

  3. Early return to agility and sport specific drills – Static drills


  1. 10 single leg squats in good balance without assistance

  2. Thigh circumference 10 & 15cm above patella


  1. Core stability & Control- Daily Abdomen, back, hip exercises

  2. Static Closed Chain Strengthening

    • Single leg squats & lunges
      • Focus on good form; progress to unstable platform, then add distraction
      • Progress to multi-plane squat around a star

  1. Progression of this Phase

    • Speed: Slow to Fast
    • Platform: Stable to Unstable
    • Condition: Known to Unknown
    • Loads: Low to Functional
  2. Aerobic conditioning:

Upper and lower extremity

Elliptical, bicycle and hydrotherapy

Clinical Follow-up

See surgeon 6-8 weeks post-op

Phase IV: Dynamic Phase

Progress if no regression, swelling, giving-way, increased pain or stiffness (soreness is normal)

Clinical Goals:

  1. Quadriceps tone continues to improve with noticeable quadriceps definition returning

  2. Return to full daily activities

  3. At least 80% strength

  4. Proprioceptive/agility specific program

  5. Complete a sport specific functional progression


  1. An isometric leg press test

  2. Isokinetic testing

  3. Crossover and 6-m timed hop tests


  1. Jumping & Landing Progression

    • Two feet to single leg
      • Double leg box jumps
      • Single leg jump in place

  • Single plane to multiplanar
    • side to side jumps both legs
    • side to side jumps single leg
    • side to side jumps single leg moving forward and then backward
  • Slow speeds to timed intervals
  • No distraction to distraction
  • Jump rope
  1. Running & Agilities

    • Lateral slides
    • Forward & Backward runnning
    • Shooting baskets, dribbling soccer ball and other sport specific drills

Phase V: Balistic

  1. More advanced Sports specific drill at competitive speeds
  2. Controlled participation in practices

Graduation from Phase V means the patient is ready to progress to practice time and supervised competition. Close observation by athletic trainer and coaches is needed to identify any red flags signifying lack of confidence, apprehension or favoring. If red flags present then may need to move back to more Phase V drills.