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PHYSIOTHERAPY ACL PROTOCOL
Rehabilitation following Anterior Cruciate Ligament Reconstruction (ACLR) is an essential part of a full recovery. This protocol is intended to provide the user with instruction, direction, rehabilitative guidelines and functional goals. The physiotherapist must exercise their best professional judgment to determine how to integrate this protocol into an appropriate treatment plan. Some exercises may be adapted depending on the equipment availability at each facility. As an individual’s progress is variable and each will possess various pre-operative deficiencies, this protocol must be individualized for optimal return to activity. There may be slight variations in this protocol if there are limitations imposed from additional associated injuries such as meniscal tears, articular cartilage trauma, bone bruising or other ligamentous injuries.
This rehabilitation protocol spans over a 6 month period and is divided into 7 timelines. Each timeline has goals and exercise suggestions for several domains: range of motion and flexibility, strength and endurance, proprioception, gait, and cardiovascular fitness. Criteria for progression within each timeline are based on the attainment of specific goals and on their Lower Extremity Functional Scale (LEFS) score. The focus in early rehabilitation is on regaining ROM, normalizing gait and activation of the quadriceps muscle. To ensure the best possible outcome for a safe return to the same level of activity prior to the injury, the client should be followed for the entire 6 months. The emphasis of rehabilitation should be focused at the 4-6 month mark. In these later stages, crucial skills such as plyometric training, agility drills, instructions on take-off and landing mechanics, patterning drills, and functional testing suggestions are given to determine the client’s readiness for return to sport/activity.
KEY POINTS
LOWER EXTREMITY FUNCTIONAL SCALE (LEFS)
The LEFS is a self report questionnaire used to evaluate the functional status of an individual with a lower extremity musculoskeletal dysfunction. It is easy to administer and easy to score in the clinical and research environment. The LEFS consists of 20 items, each scored on a 5- point scale (0 to 4). Item scores are summed and total LEFS scores vary from 0 to 80, with higher values representing better functional status. The LEFS is a reliable and valid tool for assessing change in functional status. True clinically important change has occurred if the score changes 9 or more scale points from a previous score(51). In each corresponding timeline of the protocol the ranges of the LEFS scores are presented. These scores were derived from data on 55 ACLR patients between the ages of 18-65 years of age from our facility. The LEFS scores provided should not be used in isolation as they are intended to be an adjunct to the protocol, the functional testing guidelines and to sound clinical reasoning.
PRE-OPERATIVE REHABILITATION
Rehabilitation should commence prior to surgery. After an ACL injury, deficits occur in strength(39), proprioception(40,56), muscle timing(55)^ and gait patterns(13). In fact, strength and proprioceptive alterations occur in both the injured and uninjured limb(10,21,52,55). The primary impairment with an ACL deficient knee is instability. This is manifested by episodes of ‘giving way’, which can lead to further joint damage and ultimately, long term degenerative changes(19). Research has demonstrated that physiotherapy provided pre-operatively is effective in increasing strength and balance which may limit the number the episodes of ‘giving way’ and decrease the incidence of re-injury in the ACL deficient knee(18,26). The main goals of a ‘pre-habilitative’ program prior to surgery include: full range of motion equal to the opposite knee, minimal joint swelling, adequate strength and neuromuscular control, and a positive state of mind(45). All of these factors facilitate optimal post-operative recovery. It is important to maintain the highest level of strength and function possible in the unaffected leg as it will be used for comparison to assess the progress of the reconstructed knee, in the later stages of rehabilitation(22,23).
RANGE OF MOTION & FLEXIBILITY (1,47,48)
After ACLR it is important to restore and maintain full range of motion (ROM) in the knee. Quadriceps re-training has been found to improve ROM in the early stages(44). Attaining full knee extension as early as possible is not deleterious to the graft or to joint stability(43)^ and may prevent patellofemoral pain and compensatory gait pathologies. A stretching program is incorporated to maintain lower extremity flexibility. Research recommends that a 30 second stretch is sufficient to increase ROM in most healthy people. It is likely that longer periods of time, or more repetitions, are required for those individuals with injuries or with larger muscles. Body mass has been shown to be positively correlated with muscle stiffness (i.e., the bigger the muscle, the more stiffness/tension there exists)(34). Therefore, for larger muscle groups in the lower extremity, it is suggested to increase in the number of repetitions (ie. 3- times) for optimal flexibility.
GAIT RETRAINING
Altered gait kinematics from quadriceps dysfunction is typical during the first stages post ACL reconstruction. Typical adaptations include reduced cadence, stride length, altered swing and stance phase knee ROM, and decreased knee extensor torque with hip and/or ankle extensor adaptations(11,13,15,30). Early weight bearing is advocated post ACLR in an attempt to restore gait kinematics in a timely fashion, facilitate vastus medialis function and decrease the incidence of anterior knee pain(53).
Treadmill training in the middle stages of rehabilitation can further assist in normalizing lower extremity ROM across all joints, especially with incline or backwards walking. Backwards treadmill walking has been shown in the literature to increase ROM and increase functional quadriceps strength, while minimizing patellofemoral stress. It is also beneficial for specific return-to-sport preparation requiring a re-training of backwards locomotion(49).
- Precautions with Hamstring Grafts The typical donor graft for ACLR at this facility is the hamstring (semitendinosis / gracilis). C areful measures must be taken to avoid overstressing the donor area while it heals. Although, isolated hamstring strengthening is initiated around the six-week mark in this group, it is important for the therapist to be aware of the natural stages of healing. There may be too much stress too early if the patient reports pain at the donor site during or after specific exercises.
NEUROMUSCULAR & PROPRIOCEPTIVE RETRAINING
Ideally proprioception should be initiated immediately after injury (prior to surgery), as it is known that proprioceptive input and neuromuscular control are altered after ACL injury(10,55). By challenging the proprioceptive system though specific exercises, other knee joint mechanoreceptors are activated that produce compensatory muscle activation patterns in the neuromuscular system that may assist with joint stability(9).
Post-operatively, proprioceptive training should commence early in the rehabilitation process in order to begin neuromuscular integration and should continue as proprioceptive deficits have been found beyond 1 year post ACLR(11,15,21,32). Proprioceptive exercises have been shown to enhance strength gains in the quadriceps and hamstring muscles post ACLR(31,57). In the later stages of rehabilitation, anticipated and unanticipated perturbation training is effective in improving dynamic stability of the knee(8,18). A dynamically stable joint is the result of an optimally functioning proprioceptive and neuromuscular system and functional outcome has been proven to be highly correlated with balance in the reconstructed ACL(46).
RETURN TO SPORT
Gradual return to sport is initiated at the 6-9 month mark only if the individual’s knee does not present with pain or effusion, during or after functional sport specific training drills. LEFS scores should be 76 points or greater at this point in rehabilitation. The individual must also be able to demonstrate the appropriate strength and endurance needed for their specific sport. This recommendation is based on the evidence that knee cartilage and subchondral bone are damaged during the initial ACL trauma and may need additional time to recover in order to minimize the predisposition for future joint arthrosis(17,54,58).
A further consideration when returning the patient to sport is that a cautionary approach should be taken with the use of the uninjured limb as a comparison for a rehabilitation endpoint. It has been demonstrated in the literature that a significant detraining effect occurs in the quadriceps and hamstring muscles in both injured and uninjured extremities(22).
BRACING
Bracing should be discussed with the physiotherapist and surgeon prior to return to sport or strenuous activities post ACLR. The decision will be dependent on a number of factors including: type of sport, position, activity level and complexity of the initial injury. Some surgeons may recommend a rigid, functional knee brace or a neoprene sleeve. Research has demonstrated that a rigid knee brace does not provide superior outcomes when compared with a neoprene sleeve after ACLR(6). Bracing has not been proven to prevent re-injury or improve clinical outcomes after ACLR(33). However, there is evidence that any type of knee bracing (rigid /soft) improves proprioception measures(7,27).
0-2 WEEKS
LEFS range: 14-
GOALS
- Patient education re: weight-bearing status; changes to rehab guidelines with any concurrent pathologies (i.e. PF pain, MCL injury, meniscal repair vs debridement, etc.)
- Decrease pain and swelling
- Increase range of motion & restore full extension*
- Maintain flexibility of hamstrings, calves
- Quadriceps activation(44)
- Proprioceptive/balance re-education(46)
- Maintain cardiovascular fitness
EXERCISE SUGGESTIONS
ROM & Flexibility
- Heel slides (+/– slider board)
- Supine with legs up wall – heels slides with gravity assisted
- Bike pendulums: high seat ½ circles forward/backward full circles – lower seat
- Sitting passive leg extension with roll under heel OR prone leg hangs off end of bed/plinth
- Seated calf stretch with towel - knee bent (soleus), knee straight (gastrocnemius)
- Seated hamstring stretch (back straight)
Muscle Strength & Endurance
Quadriceps/Hamstrings:
- Quadriceps and hamstring co-contraction(2,41)
- Quadriceps isometrics(44)^ in standing/sitting/lying +/– muscle stimulation or biofeedback
- Sit to stand – progress by gradually decreasing height of seat
- Static lunge forward/side
- Mini wall squat (30°)
- Shuttle: (one bungee cord) – 2 leg squat (¼ - ½ range) and 2 leg calf raises Hip/Gluteals:
- Side lying abduction/adduction
- Gluteal squeezes supine or standing
- Prone hip extension
- Standing hip flexion/extension, abduction/adduction Calves:
- Ankle pumping +/– with leg elevation
- Standing calf raises with/without support
*Remember - It is important to restore and maintain range of motion early, especially full extension. This is not detrimental to the graft or its stability (43).
3-6 WEEKS
LEFS range: 32-
GOALS
- Achieve near or full ROM in knee flexion and extension
- Continue flexibility exercises of other joints
- Continue strengthening exercises with control: hip, hamstrings, quadriceps, calves
- Strengthen non injured leg (documented strength losses in unaffected limb)(22)
- Progress proprioception
- Normal WB gait
- Maintain cardiovascular fitness
EXERCISE SUGGESTIONS
ROM & Flexibility
- Continue as needed with slider board
- Continue on the bike full with circles forward/backward - begin to lower seat
- Prone assisted knee flexion (belt, opposite leg)
- Progress to standing stretches for gastrocnemius (knee straight) and soleus (knee bent), ensure back foot is straight
- Progress to a standing hamstring stretch (keep back straight)
- Assisted quadriceps stretch in prone or in standing
- Patellar and/or tibial-femoral joint mobilizations if needed to achieve terminal ROM (no ACL strain with passive movement)(3)
Muscle Strength & Endurance
Quadriceps:
- Progress on Shuttle from 2-1 leg squats/calf raises, increase range of motion and resistance as tolerated
- Sit-to-stand with muscle stimulation(49)
- Leg press machine: low weight 2 legs (½ – ¾ range)
- Wall squats with feet 12” from wall (45°-60°)
- Forward and lateral step-ups 2-4" (push body weight up through weight bearing heel slow and with control, also watch for hip hiking or excessive ankle dorsiflexion)(4) Hamstrings/Gluteals:
- Prone assisted hamstrings (with belt, opposite leg)
- Hip strengthening with pulleys or ankle weights - all directions (do not allow a lot of trunk swaying)
- Supine on floor legs on swiss ball: isometric hamstrings/gluteals - progress to bridging (if pain free at donor site) Calves:
- Standing calf raises 2-1 foot
3-6 WEEKS continued
Proprioception
- Continue with full ROM on wobble boards with decreased support - progress to maintaining balance on board
- Standing 747 eyes open/closed – progress to mini trampoline
- Dynadisc or BOSU (round) 2 leg balance weight shift forward/backward, side-to- side, eyes open/closed progress to mini squats (0-30°)
- Standing on ½ foam roller: balance rocking forward/backward
Gait
- “Cup walking”(14): forced exaggeration of knee and hip flexion during the swing phase of gait rather than a rigid knee with a compensatory hip hike (may use plastic cups/mini pylons/foam rollers to walk over to accentuate hip/knee flexion)
- Progress from a single crutch to full weight bearing. Ensure NO antalgic gait pattern
Cardiovascular Fitness
- Bike with increasing time parameters
- May start elliptical trainer and progress to Stairmaster(36)^ if adequate strength has been achieved (must have no hip hiking when pressing down on step)
Progression of balance retraining should be from: looking forward looking away, eyes open eyes closed, on a stable base on an unstable base
*Full knee extension is needed for normal gait.
6-9 WEEKS continued
Hamstrings/Gluteals:
- Continue hip strengthening with increased weights/tubing resistance
- Supine on floor legs on swiss ball: bridging plus knee flexion (heels to buttocks)
- Prone active hamstring curls – progress with 1-2 lb weights
- Standing hamstrings curls – when able to attain 90° ROM against gravity add 1-2 lb weights
- Sitting hamstring curls with light tubing/pulley system for resistance
- Fitter: hip abduction and extension (poles for support)
- Shuttle standing kick backs (hip/knee extension)
- Tubing kickback (mule kicks) Calves:
- Shuttle heel drops 2 1 leg
- Mini trampoline: weight shift heel drops/bouncing
Proprioception
- Continue on wobble boards and begin to add basic upper body skills (i.e. throwing)
- Mini trampoline: single leg stance, +/– Bodyblade above/below head
- BOSU marching: progress with high knees
- Progress Dynadisc or BOSU 1 leg balance with/without support
- Dynadisc or BOSU squats (60-90°)
- Dynadisc or BOSU stand on 2 legs, with throwing to Rebounder™
Hydrotherapy / Pool
- Knee ROM
- Walking forward/backward, static lunge, lunge walking, squats, side shuffles, step up/down, calf raises (2-1 foot)
- Hip extension/flexion, adduction/abduction
- Deep water: stride walking, cycling, flutter kick
Cardiovascular Fitness
- Bike, increasing time or resistance
- Stairmaster: forward/backward – progress to no hand support
- Swim - Flutter kick only
- Pool jogging – deep water jogging
- Treadmill – walking, increase speed +/– visual (mirror) or auditory (metronome) feedback(12,20)
9-12 WEEKS
LEFS range: 55-
GOALS
- Continue flexibility exercises
- Quadriceps strength progression
- Address documented hamstring strength deficits (high speed, eccentric 95-60°)(23)
- Continue lower chain concentric/eccentric strengthening of quadriceps & hamstrings, both inner range (60–95°) & full range
- Proprioceptive progression
- Sport specific cardiovascular fitness
EXERCISE SUGGESTIONS
Muscle Strength & Endurance
Quadriceps:
- Progress resistance of Shuttle: full ROM and inner range (60-95°), working on strength & endurance, 2 1 leg
- Static Lunge (full range) dynamic lunge lunge walking all with proper trunk and leg alignment
- Backward step up 4-6-8”step
- Clock face lunges with Bungee using mini pylon markers
- Quick walk forward/backward with Bungee
- Quick side stepping with Bungee
- Quick lunge forward with control (upright trunk, no forward thrust, no hip hiking)
- Eccentric Bungee
- Eccentric step down with control on 6 8” step
- Shuttle jumping (low resistance) 2 legs alternate legs (jogging) single leg
- Shuttle ski hops (side-to-side)
- Continue / progress isokinetic program if patient is appropriate and equipment is available (see reference for timelines and ROM restrictions)(37)** Hamstrings/Gluteals:
- Prone/standing pulley knee flexion
- Chair walking
- Prone eccentric hamstrings with pulleys/tubing, alternating inner range and full range
- Hydrafitness (hamstrings & quadriceps): 90-30°, resistance 1-
- Continue hip strengthening with increased weights/tubing resistance
- Sitting and standing hamstring curls – Bungee/pulleys/ weights sitting and standing positions - address full range concentrically and inner range from 95-60° eccentrically and high velocity (if pain free & without difficulty)
- Supine eccentric hamstrings with knee in extension Calves:
- Eccentric heel drops
12-16 WEEKS
LEFS range: 55-
GOALS
- Continue with flexibility exercises for the lower chain
- Continue strengthening of the lower chain
- Sport specific quadriceps & hamstrings strengthening
- Sport specific proprioception training
- Sport specific cardiovascular fitness
EXERCISE SUGGESTIONS
Muscle Strength & Endurance
- Continue with concentric and eccentric strengthening of hamstrings and quadriceps, working through full & inner range
- Backward lunge – progress to backward lunge walking (with proper trunk and leg alignment)
- Bungee jogging - progress to running
- Split squat jumps – progress to BOSU
- Single leg drop landing 2” step
Agility
- Ladder drills – forward/backward, side-to-side (focus on footwork/speed/timing)
- 2 legged lateral and forward jumping
- Side step-overs (hurdle) – progress to side hop-overs
- Carioca patterning
- Tuck jumps
- Skipping
- Initiate 2 legged hop tests (hop for distance, 6-m timed hop, triple hop, crossover hop) prior to single leg hop tests in next stage - ensure patterning and landing is proficient prior to 1 leg progression
Proprioception
- Mini trampoline: 2 feet jump & land jogging 1 leg hopping (1L/1R, 2L/2R, 3L/3R…)
- Continue progressing skill difficulty
- Single leg stance – tap down clock drill with mini pylons
- Dynadisc or BOSU: 1 leg balance with upper body or opposite leg skill i.e. throwing, phantom kicking with Bungee resistance, hockey shot….
Agility is the ability to move, and change direction and position of the body quickly and effectively with control.
12-16 WEEKS continued
Hydrotherapy / Pool
- Progress to plyometrics: 2 leg hopping, forward/backward/side-to-side
- Split squat jumping
Cardiovascular Fitness
- Bike – standing with interval training
- Sport specific cardiovascular training: aerobic vs. anaerobic training
- Jogging – straight on flat ground, no cuts/no downhill
- Treadmill – jog interval running running
*Note: Progression to running may only occur once a symmetric and proficient pattern has been attained to prevent abnormal tissue/joint loading in the lower extremity. Running should NOT be initiated if swelling, loss of motion or patello-femoral pain is present.
16-20 WEEKS continued
Proprioception
- Continue progressions e.g. mini trampoline with upper skills
- Forward hop and lateral hop – maintain balance for 5 sec on landing
- Cutting drills with quick stop and maintain balance
- Bungee run plant/push off L&R
Cardiovascular Fitness
- Increase distance, duration or intensity with bike, Stairmaster, treadmill, outdoor running/cycling depending on the demands of the particular sport
- Treadmill: running sprinting: assess sprinting form - should have normal pain-free rhythmic stride (audible monitoring of foot contact)(20)
- Jogging and running on an uneven surface
- Jogging with turns 90/180/360°
- Jogging and cutting with 45° change of direction
- Acceleration and deceleration running, add on tight turns and hills as tolerated
- Cycling outdoors
- Swimming - no whipkick
20-24 WEEKS
LEFS range: 61-
GOALS
- Adequate cardiovascular fitness, strength, power, agility neuromuscular control, symmetry and stability
- Continue with upper body strengthening
- Back to sport practice for upper skills (as able)
- Return to sport skills on own at practice with minimal risk of re-injury
EXERCISE SUGGESTIONS
Plyometrics and Agility
- Single leg drop jump 6” step
- Large Figure 8's
- Carioca running full speed
- Last minute decision drills
- 2 and 1 foot hopping with control
- Forward and lateral hop with control and comparable distance L&R
- Triple jump and landing with control and comparable distances L&R
- Single limb hop for distance (within 15% of uninvolved side)
- Single-limb crossover triple hop for distance (within 15% of uninvolved side)
- Single-limb timed hop over 6 m (within 15% of uninvolved side)
- Single limb vertical power hop (within 15% of uninvolved side)
- Single limb drop landing (within 15% of uninvolved side)
- Single limb drop-jump
- 10 second single limb maximum vertical hop (both sides)
Direct correspondence to: M. Werstine HBSc(Kin), BHSc(PT), Masters Manip Ther (AUS), MSc, FCAMT Fowler Kennedy Sport Medicine Clinic Physiotherapy Department 3M Centre, UWO London, Ontario, Canada N6A 3K Phone: 519-661-2111 x Fax: 519-661-
To request a copy in pdf email: fowlerkennedypt@gmail.ca
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