Some good exercises for advanced phases of ACL rehab (phase 3 and after)
ACL rehabilitation reconstruction requires a thorough rehabilitation programme to ensure both optimal function of the knee and prevention of further injury. The long term goal should be both a return to sport, but also correction of preinjury deficits, potentially making the patient a better
athlete than before their ACL injury. ACL rehabilitation program must consider multiple factors. Following implantation the human body
will use the ACL graft as a scaffold to remodel into a ligament in a biological process that takes in excess of 12 months. During this time the ACL graft has significantly less strength than a normal ligament, so is vulnerable to injury with low force. Accompanying the “ligamentization” process are significant other deficiencies such as muscular weakness, impaired proprioception, altered muscle reaction times, impaired muscular function, and impaired neuromuscular control. The progress through rehabilitation must respect both the neuromuscular deficiencies and the biological process of healing tissue.
Stages of Rehabilitation
The phases of ACL rehabilitation after reconstruction can be considered to broadly follow 6 phases. The
goals of each stage should be achieved before progression to the next stage.
1. Prehabilitation before surgery
2. Acute Recovery
3. Strength and Coordination
4. Proprioception and Agility
5. Sports Specific Skills
6. Return to Play
Prehabilitation – Phase 1
There is considerable evidence to demonstrate that rehabilitation before surgery is beneficial to
recovery. ACL reconstruction should be performed once the knee has recovered from the acute
injury, has a full range of motion, and is pain free in order to optimise the outcome and avoid
complications such as knee stiffness. For many this may only take a few weeks, but for some it can
be several months.
Goals of phase 1 ACL rehabilitation
1. Regain pain free full range movement
2. Optimise muscular strength and function
3. Familiarise with basic post operative exercises
4. Prevention of episodes of knee instability which may cause further damage
Acute Recovery – Phase 2
In the acute period after ACL reconstruction the knee needs some time to recover from the acute
trauma of surgery. Basic gentle exercises, regular application of ice and elevation of the knee are
beneficial. The grafted ACL sees minimal force with normal daily activities and immediate weight
bearing will help facilitate return of functional strength. Most will leave hospital using crutches,
which should be used to achieve a normal gait pattern during the first week after surgery. Crutches
may also be used to avoid fatigue and alert others to disability. Crutches can be discontinued once
Goals of Phase 2 ACL rehabilitation
1. Achieve primary wound healing
2. Minimise swelling
3. Restore range of motion
4. Establish muscular control
5. Progress off crutches
Strength and Coordination – Phase 3
During phase 2 exercises can progress from simple muscular control to body weight exercises and
then to a gym based program. Any resisted ‘open chain’ quadriceps exercises should be avoided as
they can apply a strain to the ACL graft (eg leg extension machine and a freestyle swimming kick).
Intermittent episodes of increased swelling may occur, and if so exercises and
loads may need to be adjusted accordingly.
As the ACL graft progressively remodels into a ligament, its strength and load to failure decrease
such that it reaches a low of around 30% of a normal ACL around 3 months, before it then
progressively increases in strength over the subsequent 9 months. Caution should be emphasised
during this vulnerable phase of healing. Activities that involve speed or height should be avoided.
Walking is encouraged. Swimming with a kick may be commenced after 8 weeks. Before that time
swimming with a pool buoy between the legs is possible. Road bike commenced after 6 weeks if
stationary bike has been mastered, but toe cleats should be avoided.
Goals of Phase 3 ACL rehabilitation
1. Develop good muscle control
2. Recover basic balance & proprioceptive skills.
3. Reduce any recurrent knee swelling.
4. Continue to improve total leg strength.
5. Improve endurance capacity of muscles.
Proprioception and Agility – Phase 4
Once sufficient strength is achieved during Phase 2, while this needs to
be continued, the emphasis can then be directed to improving balance,
agility and proprioceptive deficits. This is an imperative stage of recovery
and adherence has the potential to dramatically reduce the risks of
further injury. Many will have pre-existing poor techniques on jumping
and landing that should be corrected. Repeat ACL injuries have been
shown to be strongly associated with poor hip rotation control, increased
knee valgus, knee flexor and postural control deficits. For jumpers
practice good landing technique = knee flexion, no valgus rotation and
toe land. Neuromuscular training has been shown to be superior to
strength training alone in terms of subjective function and hamstring
strength after ACL reconstruction.
Goals of Phase 4 ACL rehabilitation
1. Resumption of running and jumping skills with good technique
2. Recovery of balance and agility
3. Progression of muscular strength and power
4. Develop confidence
5. Prepare for sports specific skills
Sports Specific Skills – Phase 5
Resumption of sports specific drills can be commenced once the goals of Phase 3 have been
successfully achieved. It is however imperative to continue building strength with exercise selection
targeting speed of force generation/power to better replicate sporting demands. The athlete should
be able to confidently run, perform single and double leg jumping and hopping drills, as well as
change of direction activities. Consideration of the biology of the healing ACL graft remains
important, and as such sports specific skills and drills involving significant speed or height
should rarely be considered before 6 months. Several sports specific injury prevention programs
have been developed which incorporate excellent drills to perfect. Repeated practice of good
jumping, landing and change of direction drills will reinforce muscle memory and good movement
patterns. This can significantly reduce the risk of further injury. Netball Australia’s Knee Program
has excellent videos demonstrating the key principles.
Goals of Phase 5 ACL rehabilitation
1. Perfect jumping, landing and change of direction techniques
2. Regain confidence with sports specific drills and skills
3. Prepare for return to a team training environment
Return to Competitive Team Ball Sports – Phase 6
Over recent years there is increasing evidence that return to competitive team ball sports within 12
months of ACL reconstruction is associated with significant risk of repeat ACL injury.
● From a biological perspective, normal ACL graft strength and stiffness occurs after 8 months,
and the remodelling continues beyond 12 months.
● The rate of ACL reinjury has been shown to decrease by 51% for each month a return to
sport is delayed until 9 months after surgery.
● The rate of another ACL injury after 12 months is 1% per knee per year.
● Athletes who successfully pass a specific return to sport criteria have 4 times lower risk of injury
Goals of Phase 6 ACL rehabilitation
1. >90% quads strength & >90% hop symmetry
2. Completed on field sports specific rehabilitation & return to team training
3. Athlete has confidence and is comfortable to return to sports
4. Athlete understands the importance of continued injury prevention program
while active in team ball sports