ACL rehab and return to play protocol: My approach

Anterior Cruciate Ligament (ACL) reconstruction rehabilitation: what’s your stance? There are tons of different protocols and guidelines out there, and I recognize and respect that there are lots of successful approaches. As part 3 of my series (in case you missed, here’s part 1 and part 2) on the ACL, I’m sharing my personal perspective and experience in rehabilitation post-surgery. What I’m going to share is a regularly and thoroughly-reviewed approach that I’ve developed over the last 12 years, through a combination of mentors, research, and experience. One thing I really like about it is the focus on goals and objectives in each phase, regardless of rehab exercise choice. The reason I want to share my approach – being straight-forward: I’m extremely confident in my approach to ACL rehab, and I want to help others to have this same success. This is based on the highly consistent positive outcomes (both short- and long-term) of the many that I’ve guided back to beyond their normal activity level as well as positive feedback from my colleagues and peers. (Warning to the “Joes”, from here on out it may get a bit technical!)

Pre-operative “pre-hab”: I’ve found the following to be an ideal “jumpstart” to an easier first few months post-op. The amount of time b/t when the injury occurs and surgery can be anywhere from a few days to a few months. Use this “pre-hab” time wisely! Exercises

used here are dictated by the pain level, effusion amount, and injured structures involved.

Pre-op goals:
- Full ROM
- Minimal swelling/effusion
- Address any hip/lower body strength imbalances (esp. quads and hamstrings)
- Improve proprioception and balance
- Patient education – biomechanics, pain management, expectancies of operation/rehabilitation

Now it’s time for surgery. Following surgery, it is imperative that the overseeing physician(s) and rehabilitative team communicate regarding which structures were damaged/repaired and any special post-surgical restrictions to ensure safe and effective post-surgical rehabilitation with minimal (if any) setbacks.

- Special considerations:
  - When electing surgery using a hamsting (HS) tendon graft, avoid active isolated HS exercises until 2 weeks post-op, and wait 4 weeks before using open-kinetic-chain (OKC) resisted HS.
  - When electing a patellar tendon graft, main concern is monitoring and addressing signs/symptoms of patellar tendonitis if/as they arise.
  - If surgery involves a repair of meniscus, lots to consider. Note that I said “repair”, not simply a scope and shaving.
    - Brace locked at 0 deg for first 4 weeks while walking. Non weight-bearing (NWB) 0-2wks –> partial weight-bearing with crutches (PWB) week 3 –> Full weightbearing (FWB) starting week 4. Unlock brace for gait after week 4.
    - Range of motion (ROM) only to 90 deg knee flexion until 4 weeks, then progress as pain-free (to avoid “pinching” repaired meniscus).
    - No isolated HS contraction when posterior horn repair (risk of pulling on repaired structure) for 8 weeks.
    - Squat/Lunge Depth: Avoid bodyweight squatting/lunges > 60 deg knee flexion until 8 weeks; stay < 90 deg flexion until 12 weeks; avoid with rotation/twisting at knee until 16 weeks. Also delay single-leg squats/leg press until beyond 6 weeks
  - Involved MCL repair, brace 4-6 weeks, progress ROM as pain-free. No OKC HS for 6-8 weeks (since the medial hamstring tendons cross the ligament and “pulling” can impede healing).
  - Involved lateral-collateral ligament (LCL) repair, limit knee ROM 0-30 deg for 3-6 weeks, dependent on the extent of repair. Often when LCL or MCL is involved and not being repaired surgically, surgeon will elect to delay ACL surgery for up to a month to give the LCL/MCL ligament a “head-start” on healing.
  - Injury involved Posterior Cruciate Ligament (PCL) tear? No OKC active isolated hamstring exercises for 4 weeks following injury.

Ok, so now surgery has happened and it’s time to rehab. What next? Post-op, the rehab team should provide monthly progress notes to the overseeing physician until discharged. Also, as noted in parts 1 and 2, maintain awareness of any psychological/emotional/social concerns during recovery process and offer assistance. Refer to a counselor if needed. The following 5 phases are discussed assuming a straight-forward ACL repair and none of the above noted modifications are needed. Pre-protocol BONUS point: Make sure to check out the “Load/Repetition Assignment Chart” at the end of this blog. One of the biggest misjudgements of exercise prescription post-ACL (and in a lot of other rehabs for that matter) that I see is improper loading based on the goals of the phase. Why is someone STILL performing 3 sets of 10 straight leg raises with an 8# cuff weight at 10 weeks post-op?? As rehab professionals, we MUST know the load/rep continuum when prescribing our exercises. Far too many times, patients are not pushed as hard as necessary to overcome the deficits that they have in a timely (if at all) manner. Maybe it’s a fear of producing a “setback”? Well if the tremendous positive outcomes I have with my s/p ACL clients is any indication, some rehab pros need to respectfully get over that fear (while still using proper evaluative judgement). Yes, you absolutely can heavily load someone’s squat and deadlift through phase 3 and 4 (if you’ve progressed them properly leading up to it)! While we are on the topic…PROGRESS THOSE HOME PROGRAMS regularly.

Phase 1: day 1 to 2 weeks

Goals: Protect graft and graft fixation, decrease pain and swelling, control inflammation, active ROM 0-115 deg, regain quad NM control and patellar mobility, and patient educated on home exercise program for phase 1 and wound care.
Limitations: WB as tolerated with 2 crutches, brace locked in full ext for walking and sleeping, and no OKC knee extension resisted exercises
Orthotics: I recommend an accommodative foot orthosis once full WB to limit subtalar joint/midfoot overpronation –> tibial rotation –> stress to graft. Discontinue @ 3 months if desired and if gait mechanics are OK).

Some phase 1 ther-ex ideas:

Complimentary upper body and core workout (“6-sided”) program modified to protect ACL
Quad re-ed: Quad Setting w/ Russian NMS, Stick/MFR to quads, Kinesiotaping
Patellar mobility
P/A/AAROM in appropriate range based on limitations (strap, AA off end of table, AA w/ bike)
Stretches (Thomas, Gastroc, HS)
Weight Shifts
Mini Squats/Mini lunges
4-way ankle, seated/standing heel and toe raises
6-way hip (standing march, standing HS curl, Supine SLR Flx, S/L SLR Abd/add, Bent-over SLR Ext
Gait training w/ crutches (forward, backward, side step)

Phase 2: 2 weeks to 6 weeks

Goals: Regain normal gait mechanics (2 crutches –> 1 crutch –> D/C crutches as gait mechanics return), AROM full by 6 weeks, patient educated on HEP for phase 2, progressively regain strength and endurance in hips, quads, HS, and low leg with PREs as appropriate to prepare for functional activities, improve balance and proprioception, hip/ankle/patella mobility WNL and equal bilateral, and no increased knee pain or swelling during/after exercises
Limitations: No OKC knee ext PREs, and brace worn for ambulation (off for rehabilitation) until acceptable quad NM control and dynamic balance achieved
Some ther-ex ideas for phase 2:
- Continue Phase 2 ex as needed (and only if needed!)
- Complimentary upper body and core workout (“6-sided”) program modified to protect ACL
- Bike
- Begin leg press and step up/step down progression @ 4” (Fwd, Lateral, Retro)
- Begin squat progression (i.e. chair sits, variable load position, assisted –> unassisted)
- Begin lunge progression (assisted –> unassisted, multidirectional)
- Single leg and 2-leg balance exercises/weight shifts
- Gait training w/o crutch (Fwd, bckwd, side step), progressing to resisted/variable incline gait training
- Functional ADL training: stairs (fwd/bckwd), functional lifting patterns (i.e. deadlift)

Phase 3: 6 weeks to 12 weeks (maximum protection phase)

Goals: Maintain full, normal ROM, improve confidence in knee, progressively regain strength and endurance in hips/quads/HS/low leg with PREs as appropriate to prepare for functional activities (appropriate rep/load ranges), improve dynamic balance/proprioception/core stability, progress from bike to non-impact standing aerobic conditioning (elliptical, Stairmaster), aquatic jogging at 8-10 weeks <50% WB (when available and if wounds fully healed)
Ther-ex ideas:
- Continue Phase 1& 2 ex (only if needed, otherwise move on)
- Scar desensitization/patellar mobility
- Progress bilateral and unilateral squat variations
- Progress deadlift variations
- Progress multidirectional lunge variations
- Progress dynamic balance exercises
- Progress core/glute/lateral hip stabilizers (hip hikes, mini band walking, bridging/plank/side plank series, RNT)
- HS strengthening (esp. eccentric): RDLs, seated HS curls, Ball/TRX curls, Russian hamstrings
- Jogging prep -“Non-impact” jogging, elliptical, Stairmaster, bike sprints

Phase 4 : 12 weeks to 20 weeks – Before progressing, perform 3 month functional knee assessment (see Index)

- Expectations at 12 weeks:
  - Knee AROM WNL and pain-free
  - 12” Lateral Step Down technique correct, symmetrical, and endurance within 10% of unaffected leg
  - Quads strength and endurance within 20% of unaffected
  - HS strength and endurance within 10% (may be delayed when limited by posterior horn lateral meniscus and/or MCL/LCL involvement)
  - Dynamic balance within 10% of unaffected leg
  - Girth within 5% of unaffected (mid patella, 3” superior to patella, 1/2 way b/t patella and ASIS)
  - Core stability endurance w/i 5% ant/post/right/left (Goal = 90 seconds)
Phase 4 Goals: Develop good dynamic hip/knee/ankle strategy, initiate progressive intensity/volume jogging program as appropriate, modified “Couch to 5K” progression (see index), initiate progressive plyometric program (as appropriate) focusing on training force absorption NM control, and initiate progressive intensity agilities (linear –> multidirectional) as appropriate.
Limitations: Can utilize OKC knee ext in the range of 90-30 degrees after week 12 (focus on eccentrics and utilize resistance point more proximal on tibia), and be cautious of impact training volume, avoiding recurrence of swelling/loss of motion.
Ther-ex ideas:
- - Continue Phase 1-3 ex as needed
  - Address any “less than ideal” 12-week functional knee assessment findings
  - Force absorption/creation training: (quick drops, quick hops, jump/landing training)
  - Jogging progression (see index)
  - Continue to address any remaining LE strength deficits,
    with focus on strength and power development (8 or less rep range, appropriate loads)

Phase 5: 20 weeks and beyond: now it’s time for the 5 month “Functional Knee Assessment

- - - Expectations at 20 weeks:
      - No patellofemoral or soft-tissue complaints (if present, must be minimal and patient effectively able to self-manage).
      - 12” Lateral Step Down technique correct and symmetrical, and endurance equal bilateral
      - Normal gait (walking and running) mechanics and appropriate dynamic biomechanics (jump/landing technique, avoidance of dynamic genu valgus, postural proprioceptive control)
      - Functional Movement Screen score >15/21 with no scores of “1”
      - Dynamic balance symmetrical
      - Quads and hamstring strength and endurance within 5% of unaffected leg and HS/Quad ratio b/t 65-75%
      - Core stability endurance w/i 5% ant/post/right/left (Goal = 90 seconds)
    - Phase 5 Goals: Progressive, full return to beyond pre-injury speed/agility/power/conditioning and level of activity/sports with goal of full return to sport at 6-9 months (return to sport time-frame varies dependent on risk of sport and age/physical maturity/injury history of athlete). Resolve any residual lower extremity weaknesses or functional deficits noted in a full functional movement assessment, and educate patient regarding maintenance home exercise program, progression of training volume (varies per sport/activity), and any possible remaining limitations.
    - Bracing: I recommend the use of a knee brace for 1 year for contact/potential-contact sports

FInally, here’s the phase 5 return-to-sports volume progression that I use. This will vary per sport, athlete age, and injury history. It’s important to continue to incorporate strength, power, balance, and core training into routine weekly. In the event that mild swelling or knee pain occurs that lingers constantly for more than 2 days, no practice/games for 3 days. If symptoms resolve, return to play as instructed. If symptoms do not resolve, follow-up with sports medicine team. The athlete only moves on to next “phase” if able to tolerate current phase without swelling or knee pain occurring. I also remind them that it is normal to feel “achy” in knee during times of increased intensity and volume more than normal, especially around patella and in area of scar. As long as this does not cause swelling and ceases shortly following activity, there is no reason for concern.

- - Weeks 17-20 (Month 5):
    - Focus on improving multidirectional agilities in a controlled setting (no “live” drills @ practice)
    - Focus on increasing speed, power, endurance, and improving sport-specific skills
  - Weeks 21-24 (Month 6):
    - Gradual return to sports/practice participation
    - “1 on, 1 off” practice schedule:
      - This pertains to “live” drills, and not sprints/aerobic conditioning or controlled-intensity skill work. This means that every other practice, athlete takes part in “live, game-like drills”.
      - In game-like scrimmaging, volume is limited to no more than that equal to ¼ of a full game
      - No participation in games
  - Weeks 25-28 (Month 7):
    - “2 on, 1 off” practice schedule first two weeks, then “3 on, 1 off”.
      - This pertains to “live” drills/scrimmaging at practices, and not sprints/aerobic conditioning or controlled-intensity skill work.
      - In game-like scrimmaging, volume is limited to no more than that equal to 1/2 of a full game for first 2 weeks, then ¾ of a full game next two weeks
      - No participation in games 1^st two weeks, then playing no more than ½ of game next two weeks
  - Beyond week 28 (Month 8):
    - Full practice/game participation. No restrictions. Continue to work on balance, strength, flexibility, and conditioning in conjunction with sport-specific skills.

Load/Repetition Assignments Based on Training Goal


Training Goal	Load (% 1RM)	Goal Reps
Strength	85+	< 6
Power: Single-effort eventMultiple effort event	80-90 75-85	1-2 3-5
Hypertrophy	67-85	6-12
Muscular Endurance	< 67	> 12
Accommodation	50-75	10-15
Re-patterning/NM Re-ed	0-50	>20