On to topic #2 from @ACLStudyDay home study session:

Return to run post-ACLR with @rwilly2003 ! Notes to follow in this thread...

Resolving basic fundamentals is impt prior to running - edema, ROM, strength, etc - or these impairments may persist/be magnified once pt returns to running

Recreational running may become exercise of choice for some athletes who choose NOT to return to pre-injury sport

Little evidence supporting that running is harmful to those with knee OA!

**Caution: we don't know long-term data on running post-ACLR.

Post-op impairments that must be addressed:
- pain
- psych
- ROM
- muscle force production
- effusion
- altered coordination

Running:
- 2.5x BW on impact
- 5-6BW's of TFJ and PFJ contact force
- rapid energy storage/release, cumulative loads + these peak loads
- avg 10k run, runner takes 7000 foot strikes

***Consider how these loads increasein other running sports (jumping, sprinting)

"Heavy, slow resistance training is the absolute foundation for recovery for all our athletes for return to sport and return to daily activities."

Load progression:

Heavy, slow resistance training --> plyometrics --> graded return to running

Impaired running biomechanics do NOT seem to "smooth out" as post-ACLR pts continue to run. Need to address during rehab.

Post-ACLR running biomechanics:
- Peak VGRF not different between limbs
- impact forces (loading rates) not different between limbs
- BUT individ w/ quad weakness have LOWER peak VGRF (can't control load as well, but this doesn't allow efficient storage/release of energy)

Post-ACLR running biomechanics:

- At footstrike: land in greater knee flexion
- At midstance: Decr peak knee flex, decr knee flex excursion, & decr knee extensor moment. Incr PFJ contact force/stress due to knee angle.

Load shifts off knee & onto hip after partial meniscectomy (Willy 2017 KSSTA) - similar mechanics seen post-ACLR.

KOOS QOL predicted these load shifts. As knee confidence decr, load to knee decr, load to hip incr.

Individ scoring >=85% LSI hop tests and Cincinnati Knee Pain Score assoc w/ higher peak knee external movement & peak VGRF than those <85% (Perraton 2018 KSSTA).

Hopping and running intricately related.

Post-ACLR, 30% of pts will experience PFP, REGARDLESS OF GRAFT TYPE.

Peak PFJ stresses during running 23% greater in ACLR than opp limb, 25% greater than healthy matched controls.

(Herrington AJSM 2017, Culvenor JSMS 2016)

Quad function is a predictor of knee biomechanics during running post-ACLR! (Kline 2016 MSSE)

Return to run post ACLR review Rambaud BJSM 2018: https://bjsm.bmj.com/content/52/22/1437.long
In lit,
- Avg @ 12 wks post-op
- only 1/5 studies used add'l criteria!

Recs for RTRun:
- full ext ROM
- flex within 5% opp limb
- pain <=2/10 VAS
- absent/trace effusion
- HS&Quad LSI >70%
- Hop tests >70%

Rich's recs (modified Rambaud):
- full ext ROM
- flex within 5% opp limb
- min/absent pain w/ repetitive hops
- absent/trace effusion
- HS&Quad LSI >=80%
- Iso quad torge 3.0 Nm/kg
- Hop test >70% LSI
- Walk 7000 steps/day, 4000/bout
- IKDC >=70%
- min 12 wks post ACLR

Quad strength testing: Isometric dynamometry best.
- 5 sec hold make test
- Torque = force x moment arm length.
- Force (kg) x 9.81 to get N
- Moment arm length = dynamometer to lat fem condyle
- Divide by body mass to get N*m/kg
- Avg values post-ACLR quad torque 3.0-3.2 N*m/kg

Base resistance training based on 1RM (ACSM position statement, MSSE 2009):

Use 1RM calculator app (free) which estimates your 1RM based on weight and reps you can do

Goal: train at least >=75% 1RM to gain strength

Quad program example: DAPRE protocol (Herrington & Al-Sherhi JOSPT 2007):
1) determine 6 RM
2) set 1 = 10 reps 50% 6RM
3) set 2 = 6 reps 75% 6RM
4) set 3 = max reps 6RM
5) set 4 = adjusted based on set 3 (Table 3)

https://www.jospt.org/doi/10.2519/jospt.2007.2433

OPEN CHAIN EXERCISE DOES NOT STRETCH OUT THE ACL GRAFT

- need to isolate quads

ACL strain
Resisted squatting = 4%
OKC knee ext to 30 deg = 4%
Walking = 13%

Graft was a tendon - needs loading to mature!

Add plyometrics when effusion <= 1+, full ROM, quad index >60%

Start:
- stationary hop unilateral
- forward hop unilateral

Suggested pgm:
Mon 3x10
Wed 3x15
Fri 3x20
Next week progress

Return to run programs - graded exposure!

"Hard days" with running, "easy days" cross-training every other day. Perform resistance training on (before) running days.

Consider having athletes use objective app to help with timing:

Example: "Interval Timer - HIIT Training" (for Android and iPhone):
- can program warmup, interval and cool-down
- alarm will sound over music when it's time to switch

Soreness rules! (pain >=2/10 VAS)

Continue w/training pgm IF:
- no pain during/after warmup
- pain during warmup but goes away

GO BACK 1 STEP, add x-training day:
- pain or effusion>trace next day

STOP, GO BACK:
- recurrent pain during warmup or session persists/worsens

Stroke test (Sturgill 2009) for effusion

https://www.jospt.org/doi/10.2519/jospt.2009.3143

Treadmill and overground running very similar in terms of:
- TFJ loads, both for total peak TFJ & medial compartment
- PFJ loads

(Willy JOSPT 2016)

Change shoewear?
NOT WORTH INJURY RISK.

- Sure, minimalist shoes reduce PFJ loads, but they increase Achilles tendon loads (might not be a great tradeoff)

For athlete w/persistent knee pain and/or effusion with running:

- avoid downhills (due to higher ecc loads)
- do more uphill running (incr pf & hip loads), ideally on treadmill @3-5% grade
- slow jogging tends to worsen sx (longer ground contact time) - speedwork reduces loads

Can increase cadence/step rate 5-10% as well:

- decr PFJ loads by 15-20%
- decr TF contact forces by 7.5-11%

How to address asymmetrical loading pattern:
- can't just increase cadence (asymmetry persists)
- use metronome for external pacing

SUMMARY KEY POINTS:
- Quad strength critical
- hopping as bridge to running
- time and performance-based criteria to clear to run
- address biomechanical changes early
- use an app to guide dosage

/end