robertson acl management
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TRANSCRIPT
Non-Operative Management of the ACL-Deficient KneeConservative Management of ACL
Lecturer:
Eric Robertson, PT, DPT, Assistant Professor
Regis University, Denver, CO
University of Texas at El Paso, El Paso, TX
Objectives
• Describe usual care following ACL injury• Define the terms Copers and Non-Copers• Describe the characteristics of Copers versus Non-copers• Explore the impact of psychological factors in prognosis and
outcomes• Examine outcomes following conservative management of ACL
injury• Review evidence-based interventions for non-operative
management of the ACL-deficient knee
It’s a paradigm
Currently, there are over 80,000 ACL injuries in the U.S. each year. Over 90% of those will be surgically repaired.
Cochrane SR, 2005, Benjaminse, 2006
It’s a paradigm
ACL reconstruction costs $3 billion each year.
It’s a paradigm
It’s not been demonstrated that operative management of ACL injury is superior to non-operative management.
It’s a paradigm
It’s not been demonstrated that operative management of ACL injury is superior to non-operative management.
It’s really true
Surgical time correlated to $$
23 min = $1000
=
Bonsell, 2000
Why do orthopedic surgeons recommend ACL reconstruction following injury?
• Restore knee stability• Prevent meniscal damage• Protect articular cartilage• Avoid degenerative
changes
• All these are theoretical concepts, with various levels of support in literature.
• Who might be non-surgical candidates?• Seasonal, construction workers• Athletes with a need to compete
(scholarship, perhaps?)• Low activity level
• Is there a way we can figure out who can function without an intact ACL?
What do we think?
Let’s have a brief discussion. Is ACL repair a lemon?
Risk Factors for post-ACL OA?
• ACL Injury• ACL Repair• Opting out of ACL
Repair
• Meniscal Injury• Meniscetomy at time
of injury or before• Chondral Lesions
OA incidence is the same if you have surgery or if you don’t.
Streich et al, 2011
“We observed significantly better knee-stability (P = 0.008) but more osteoarthritis (Grade II or higher)
after ACL-reconstruction (42% vs. 25%)”
Kessler et al, 2008
“Eleven years after ACL-rupture the physical activity levels are similar for both groups.”
Risk Factors for post ACL OA?
• ACL Injury• ACL Repair• Opting out of ACL
Repair
• Meniscal Injury• Meniscetomy at time
of injury or before• Chondral Lesions
Risk Factors for post ACL OA?
•ACL Injury• ACL Repair• Opting out of ACL
Repair
• Meniscal Injury
•Meniscetomy at time of injury or before• Chondral Lesions
Risk Factors for post ACL OA?
•ACL Injury
•Stability
Stability of the Knee• Dynamic• Kinestheic awareness• Proprioception• Muscle strength and control• Balance• Core Stabilility
• Static• Ligamentous• Meniscii• Ability to achieve screw home mechanism (full extension)
Can some people cope without an ACL?
Is there enough dynamic support to stabilize the knee sufficiently for function?
Coper
Those individuals who can dynamically stabilize an ACLD knee.
• Must resume previous activity• No episodes of giving way• Do not require surgery
• Activity persists for up to one year, (perhaps)
Non-Coper
Those individuals who can’t dynamically stabilize an ACLD knee.
• Giving way• Unable to resume previous level of activity• Require surgery
Note…
Being a coper or a non-coper does not seem to predict surgical outcomes.
% of ACLR Achieve Full Return to Activity
Copers Non-Copers
8-82% 19-82%
Comparing Copers vs Non-Copers
• Kinematic Differences• EMG Differences• Functional Differences• Activity Differences
Kinematic Differences
Copers
• Joint stability• Fewer episodes of giving
way• Somewhat normal knee
ROM and forces during functional activities and gait
Non-Copers
• Increased joint laxity• Reduced knee ROM
during hop tests• Reduced knee
compression and shear forces during gait
EMG Differences
Copers
• Poor quadriceps control• Preferentially utilized a
vastus lateralis and medial hamstring activation pattern during a cutting drill
Non-Copers
• Poor quadriceps control• Increased quadriceps
activity during knee flexion activities
• Increased co-contraction strategies
Functional Differences
Copers
• Increased IDKC scores• Increased fuctional scores• Improved single-limb hop
tests
Non-Copers
• Reluctance to participate• Fear avoidance
Activity Differences
Copers
• Return to Activity: 82%
• Return to activity is limited
• Reduced activity scores ~21%
• Self-reports: overall good knee function
Non-Copers
• Return to Activity: 82%
• Return to activity is limited
• Reduced activity scores ~21%
• Self-reports: overall good knee function
IDENTIFICATIONWho can cope with ACLD?
U of Delaware Screening Examination
Moksnes H, Snyder-Mackler L, Risberg MA. Individuals with an anterior cruciate ligament-deficient knee classified as noncopers may be candidates for nonsurgical rehabilitation. J Orthop Sports Phys Ther. 2008;38(10):586-95.
Identifying Copers (Fitzgerald, 2000)
Potential Copers:
• 1. < 1 episode of giving way• 2. > 80% 6m timed hop test• 3. > 80% KOS ADL subscale
• 4. > 60% Global Rating of Knee Function
Prevalence of True Copers
True Copers Non Copers• Fitzgerald, 2000; Hurd 2008• 42%
• Moekses• 37%
• True Copers can return to function without surgical reconstruction.
• 63% but…maybe shouldn’t classify them right away…
• Of Non-copers, 70% were classified at Copers at 1-year follow-up
• Summary: 63% of subjects were copers
Moksnes H, Snyder-Mackler L, Risberg MA. Individuals with an anterior cruciate ligament-deficient knee classified as noncopers may be candidates for nonsurgical rehabilitation. J Orthop Sports Phys Ther. 2008;38(10):586-95.
When do I measure?
Optimal Evidence-based Time Frame for Coper Determination:• After a period of rehabilitation, after 60 days,
before 6 months• 10 sessions has been a reported treatment duration
Psychological Factors!
“Patient psychological factors are predictive of ACL reconstruction outcomes.” Everhart, 2013 Systematic Review
Psychological Model of Pain Perception(Linton and Shaw, 2011)
Specific Psychological Pain Models(Linton and Shaw, 2011)
• Fear-avoidance• Acceptance and commitment• Misdirected problem solving • Self-efficacy • Stress-diathesis
Specific Psychological Pain Models(Linton and Shaw, 2011)
• Fear-avoidance• Acceptance and commitment• Misdirected problem solving
• Self-efficacy • Stress-diathesis
Fear-Avoidance Model(Linton and Shaw, 2011)
• Attention • Fear/Injury keys attention to internal stimuli (hyper-vigilance)
• Cognition • This is pain/event catastrophizing
• Emotion • Fear, depression, and anxiety
• Behavior • Activity avoidance is hallmark of the model
Fear-Avoidance Model (Leeuw et al, 2007)
Misdirected Problem Solving(Linton and Shaw, 2011)
• Attention • Continuing pain/condition demands attention
• Cognition • Beliefs that there is an identifiable cause of pain/circumstance
• Emotion • Worry is the primary one here
• Behavior • Attempts (continued) to solve the problem
Misdirected Problem Solving (Eccleston et al, 2007)
Self-Efficacy(Linton and Shaw, 2011)
• Attention • Not emphasized much in this model
• Cognition • Beliefs related to locus of control
• Emotion • Not emphasized much in this model
• Behavior • Coping skills
Self-Efficacy(Bandura, 1997)
• Model summary • “the belief in one’s capabilities to organize and execute the
courses of action required to produce given attainments” • Low self-efficacy accompanied by beliefs that pain/rehab is
uncontrollable • High self-efficacy may be feature of self-management
Low Self-Efficacy Example
• “I hope the doctor knows what he’s doing in surgery. I really need this to go right so I can return to my sport.”
High Self-Efficacy Example
• “I’m going to play football again, and quite frankly, I don’t care what the doctors say.”
Communication Keys
• Physician research for effective patient communication (Maguire and Pitceathly, 2002)• Style and focus• Eye contact • Active listening
• Facilitation of self-disclosure • Patient concerns • Explicit interest and consideration of psychosocial factors
Clinical Application
• Be confident• Be positive• Clearly explain the problem in current framework for pain
perception • Come to an agreement about the nature of the problem and the
way to treat it.
Psychologically Informed Intervention(Nicholas and George, Phys Ther 2011)
• Model of communication
• Cognitive-behavioral methods
Cognitive Behavioral Methods(Nicholas and George, 2011)
• Analysis • Observe when/where problem behaviors occur and consequences • Identify beliefs/expectations associated with problem behaviors • Develop a formulation of relationships between these domains
Cognitive Behavioral Methods(Nicholas and George, 2011)
• Change plan (involves patient) • Identify goals the patient wants to achieve • Breakdown into specific sub-goals that can be up-graded • Especially important for quota or exposure approaches
• Develop plan for dealing with obstacles • Plan for reinforcement when successful
Cognitive Behavioral Methods(Nicholas and George, 2011)
• Implement plan• Explain to patient the formulation of problem behaviors (including
pain) and obtain agreement • Ensure patients works on upgrading activities that were previously
avoided • Help patient problem solve obstacles • Provide skills training as needed • Monitor and reinforce when successful • Terminate treatment when goals are met
Psychologically Informed Intervention(Nicholas and George, Phys Ther 2011)
• Model of communication
• Cognitive-behavioral methods
• Treatment approaches
Psychosocial Pain Treatment (Jensen, 2011)
• Clinical approaches• Hypnosis • Relaxation training • Mindfulness meditation training • Operant treatment (e.g. graded exercise) • Graded exposure • Motivational interviewing • Cognitive and cognitive behavioral therapies• Acceptance based cognitive therapy
Psychosocial Pain Treatment (Jensen, 2011)
• Clinical approaches• Hypnosis • Relaxation training • Mindfulness meditation training • Operant treatment (e.g. graded exercise) • Graded exposure • Motivational interviewing • Cognitive and cognitive behavioral therapies• Acceptance based cognitive therapy
GRADED EXERCISE (ACTIVITY)
Fear-Avoidance Model (Leeuw et al, 2007)
Fear-Avoidance Beliefs Assessment
• Fear-Avoidance Beliefs Questionnaire used to screen for elevated fear-avoidance beliefs (Waddell et al, Pain, 1993) • “Physical activity might harm my knee” (0-6)• “I should not do physical activities which (might) make my pain
worse” (0-6)• “I do not think I will be back to normal anytime soon” (0-6)
Kinesiophobia Assessment
• Tampa Scale of Kinesiophobia (TSK) is also used to assess pain-related fear and fear of re-injury
• Originally 17 items, now an 11 item scale (TSK-11) is recommended (Woby et al, 2005) • “I’m afraid I might injury myself if I exercise” (1 – 4) • “Pain always means I have injured my body” (1 – 4)
Tampa Scale of Kinesiophobia (TSK-11)
(Woby et al, 2005)
SUM
Pain Catastrophizing Screening
• Pain Catastastrophizing Scale (PCS) used to screen for elevated pain catastrophizing (Sullivan et al, 1995). • “I worry all the time about whether the pain will end” (0-4) • “I keep thinking about how much it hurts” (0-4)• “There’s nothing I can do to reduce the intensity of the pain” (0-4)
Pain Catastrophizing Screening
SUM
Sport / ACL Specific Measures of Psychological Factors
• ACL – Return to Sport After Injury scale• 11-item scale• ‘‘Are you fearful of reinjuring your knee by playing sport?’’ and ‘‘Are you
confident you can perform at your previous level of sports participation?’’
• The Incredibly Short Profile of Mood States• Rate: anxiety, sadness/depression, energy, fatigue, anger on 5-point scale from
“nothing” to “extreme”
• TSK
• Sport Rehabilitation Locus of Control• 5-point scale, “agree” or “disagree with statements• ‘I’m in control of my rehabilitation and return to sport’’ and ‘‘If it’s meant to
be, I’ll get back to sport’’
Arden et al, 2013 AJSM
Arden et al., 2013
• “Clinical screening for maladaptive psychological responses in athletes before and soon after surgery may help clinicians identify athletes at risk of not returning to their pre-injury level of sport by 12 months.”
Education Modifications
“…unambiguously educating the patient in a way such that the patient views his or her pain as a common condition, rather than as a serious disease that needs careful protection.”
(Vlaeyan and Linton, Pain, 2000)
When to Intervene?
Injury Return to Sport
Early after Injury, pre-operatively, and early in rehab process seems more effective for influencing psychological barriers with ACL injury
Graded Exercise
• Principles • Based on operant conditioning principles (Fordyce et al, Arch
Phys Med Rehabil, 1973) • Primary intervention goal is increase in activity through quota
attainment• Intervention does not focus on symptom abatement
Graded Exercise
• Basic treatment flow • Include a variety of general exercises or activities • Determine exercise or activity tolerance • Set quota based on exercise or activity tolerance• Hold patient accountable to quota attainment • Reward quota attainment NOT pain behavior• Goals remain focused on functional gains • Repeat process
GRADED EXPOSURE
Fear-Avoidance Model (Leeuw et al, 2007)
Specific Fear
• Vlaeyen et al suggests measurement of specific fears more relevant to patient
• May be necessary for certain treatment protocols
Specific Fear
• Beyond the FABQ or TSK or PCS • Need to measure fear of specific activities• PHODA-SeV (Leeuw et al, 2007) (Pictures)• 20 movements/activities presented to subjects • Rate fear of each one on VAS (electronically) • Consider highly rated movements/activities to intervention
Fear of Activities
• Fear of Daily Activities Questionnaire (FDAQ) used to identify fear of specific activities
(George et al, Phys Ther, 2009) • 10 movements/activities presented to subjects • Rate fear of each one on VAS• Average the first 10 items for FDAQ score • Consider highly rated movements/activities to intervention
Scan for highly rated activities to include for intervention
AVERAGE (10 Items)
Graded Exposure
• Vlaeyen et al suggests as a more effective alternative than quota driven approaches
• What is the difference?• Graded activity = increase in generic functional capacity (operant
conditioning model)• Graded exposure = increase in activities that are fearful
(exposure/phobia model)
• Differences have not been tested (much)
Graded Exposure
• Basic treatment flow • Identified activities or exercises that are fearful• Determine initial exposure level • Gradually increase exposure based on decreased fear and
anxiety • Hold patient accountable to increasing exposure • DO NOT reward pain behavior• Incorporate exposure as part of home program • Repeat process
OutcomeHigh fearPrognostic factor
Treatment Moderator
High fear
Treatment A
Treatment B
↑ Outcome
Outcome
Low fear
Treatment A
Treatment B
Outcome
↑ Outcome
Treatment Mediator Treatment
Fear
Outcome
Outcome
Decision Aides
Treatment Monitoring
Hill and Fritz, Phys Ther, 2011
Treatment Moderating Factor
• Makes treatment effect greater in one group vs. another • When or among whom does an effect “work”?
• Source of treatment effect heterogeneity
• Decision Aide
High fear
Treatment A
Treatment B
↑ Outcome
Outcome
Low fear
Treatment A
Treatment B
Outcome
↑ Outcome
Treatment Mediating Factor• Mediator variables are part of the mechanism through which
treatment impacts the outcome. • The effect of treatment on an outcome involves intervening
changes in mediator variable
• Treatment Monitoring
Treatment
Fear
Outcome
How about Psychological Factors and Copers vs Non-Copers?
• Kartigan et al., JOSPT 2013 Nov
• “Kinesiophobia after ACL Rupture and Reconstruction: Non-Copers Versus Potential Copers”
Kartigan et al., JOSPT 2013 Nov
• 50 copers• 61 non-copers• Examined functional outcomes and kinesiophobia after
injury and 6 months post-surger• (all copers and non-copers had surgery)
Kinesiophobia: Non-copers
Pre-Surgery Post-Op
70
10
*Graphical representation, not real scores
Kinesiophobia: Potential Copers
Pre-Surgery Post-Op
30
10
*Graphical representation, not real scores
Key points
• Non-copers had higher levels of kinesiophobia pre-operatively, but greater reductions when measured post-operatively compared to potential copers.
• Kinesiophobia is higher pre-op than post-op, regardless of performance on functional measures.
• Kinesiophobia should be measured throughout rehab. (plateaus at ~6 months?)
Components of Rehabilitation Program
• Rehabilitation looks similar to post-operative rehabilitation and many of the same principles apply• Optimize quad function• Minimize swelling• Maximize ROM• Neuromuscular re-education
Restoring Quadriceps Function
• Quad Sets• Straight Leg Raises• With and without
Biofeedback• Active Knee Extension
Against Gravity: No Added Resistance
Fitzgerald GK, Piva SR, Irrgang JJ. A modified neuromuscular electrical stimulation protocol for quadriceps strength training following ACL reconstruction. JOSPT 2003 33(9): 492-501
• 2500hz, 75 burst/sec• 10 contractions• 10 on/ 50 off• Stimulus produces
full, sustained quad contraction with evidence of superior patellar glide
NMES
Lower Extremity Strengthening
• Initiate closed chain exercise with body weight when patient can fully weight bear without crutches.• Double and single leg squats
(0-45)• Lateral and forward step ups• Calf raises (up on toes)
• Progress to leg press when tolerating 3 sets of 15 reps for two consecutive sessions without pain, swelling, instability
• No significant difference in anterior knee laxity at 6 months
• Significant increase in quadriceps torque in the CKC/OKC group
• Significant higher number of patients returned to pre-injury sports level in the CKC/OKC group and did so 2 months earlier than the CKC group
• Conclusion: Incorporate OKC exercises with CKC exercises in the protected ranges following ACL Reconstruction
Mikkelsen C, Werner S, Eriksson E. Closed kinetic chain alone compared to combined open and closed chain exercises for quadriceps strengthening after anterior cruciate ligament reconstruction with respect to return to sports: a prospective matched follow-up study. Knee Surg, Sports Tramatol,
Arthrosc. 2000; 8: 337-342.
Lower Extremity Strengthening
• Begin leg press with double leg and eventually progress to single leg
• Begin with 50 to 75% of body weight
Arc of Motion = 0 to 45
Restore Balance and Proprioception
• Altered proprioception and lower extremity muscular control has been associated with ACL Injury
• Unclear if these deficits fully resolve after ACL reconstruction
• Functional retraining programs for post-op ACL rehab may need to emphasize enhancement of lower extremity neuromuscular control strategies
Criterion Based Progression
• Running• Pool Run (week 6)• Treadmill Run (week 8)• Normal gait pattern while walking• Quad strength = 70% of uninvolved limb• Minimal effusion with minimal pain
Suggested Progression from Adams et al. JOSPT 2012
Criterion Based Progression
• Agility Training• Track or Road Running for
1 to 2 miles without pain, swelling, instability
• Quad Strength = 80% of uninvolved limb
• Begin agility activities with 50% effort, progress to 75% then 100% effort provided no pain, swelling, instability
Criterion Based Progression
• Sprinting• Tolerating all agility and low level sport
specific training.• Quad strength 85 to 90% of uninvolved
limb• Begin with form running at 50 and 75%
effort, progress to 100% when tolerating these without pain, swelling, instability
• Lower Level Sport Specific Training• Tolerating all agility training at
100% effort without pain, swellling, or instability
• Quad function = 85% of uninvolved limb
Identifying Copers (Fitzgerald, 2000)
Potential Copers:
• 1. < 1 episode of giving way• 2. > 80% 6m timed hop test• 3. > 80% KOS ADL subscale
• 4. > 60% Global Rating of Knee Function
Return to Sport
• Tolerating 100% effort sprinting, agility drills, jumping, and hopping• No evidence of compensation or valgus collapse• No pain or reports of pain as progression continues• No reports of giving way• No effusion or signs of inflammation
• Begin with opposed practice of sport specific skills (training partner)
• Return to practice with team when tolerating opposed practice of skills.
• Return to sport when no difficulty with all practice activities.
Components of Rehabilitation Program
• Include Open-Chain Exercises• Taggesson, 2008 – no differences btwn OKC/CKC in observed
dynamic tibial translation• OKC may significantly improve quad strength• NMES
• Include kinesthetic awareness training
• Include perturbation training• Enhance ability to protect joint• Neuromuscular component
• Key Outcome: Resume previous level of activities, usually within <6 months to 1 year.
Bracing
• Functional knee bracing does not seem to improve proprioception following ACL reconstruction even at 2 years after surgery.
• Bracing produced significantly more thigh atrophy at 3 months after surgery than did non-bracing.
• Bracing does not appear to influence either objective stability or subjective function.
• Some researchers have concluded that functional braces may expose athletes to additional risk by imparting a false sense of confidence.
A note about joint health…
• One study reported a reduced rate of surgery using conservative therapy and optional ACLR, however…• Increased rates of meniscal tear/damage noted
• Rates of Knee OA increased with ACL injury regardless of management decision
Choosing Surgery
• Remains gold standard for athletes, especially higher level, requiring pivoting skill
• Complex and multifactorial for everyone else
• Choosing surgery not correlated with better outcomes
It’s a paradigm
Currently, there are over 80,000 ACL injuries in the U.S. each year. Over 90% of those will be surgically repaired.
Cochrane SR, 2005, Benjaminse, 2006
References:• Eitzen, Ingrid, Havard Moksnes, Lynn Snyder-Mackler, Lars Engebretsen, and May Arna Risberg. “Functional Tests Should Be
Accentuated More in the Decision for ACL Reconstruction.” Knee Surgery, Sports Traumatology, Arthroscopy: Official Journal of the ESSKA (April 22, 2010). doi:10.1007/s00167-010-1113-5.
• Fitzgerald, G K, M J Axe, and L Snyder-Mackler. “A Decision-making Scheme for Returning Patients to High-level Activity with Nonoperative Treatment after Anterior Cruciate Ligament Rupture.” Knee Surgery, Sports Traumatology, Arthroscopy: Official Journal of the ESSKA 8, no. 2 (2000): 76–82.
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• Grindem, Hege, David Logerstedt, Ingrid Eitzen, Håvard Moksnes, Michael J Axe, Lynn Snyder-Mackler, Lars Engebretsen, and May Arna Risberg. “Single-legged Hop Tests as Predictors of Self-reported Knee Function in Nonoperatively Treated Individuals with Anterior Cruciate Ligament Injury.” The American Journal of Sports Medicine 39, no. 11 (November 2011): 2347–2354. doi:10.1177/0363546511417085.
• Hurwitz, D E, T P Andriacchi, C A Bush-Joseph, and B R Bach Jr. “Functional Adaptations in Patients with ACL-deficient Knees.” Exercise and Sport Sciences Reviews 25 (1997): 1–20.
References:• Irrgang, J J, and G K Fitzgerald. “Rehabilitation of the Multiple-ligament-injured Knee.” Clinics in Sports Medicine 19, no. 3 (July 2000):
545–71.• Lewek, Michael D, Terese L Chmielewski, May Arna Risberg, and Lynn Snyder-Mackler. “Dynamic Knee Stability after Anterior
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Ligament Reconstruction: a Comparison with Non-operative Treatment with a Follow-up of 17-20 Years.” International Orthopaedics 35, no. 7 (July 2011): 1093–1097. doi:10.1007/s00264-011-1206-x.
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• Moksnes, Håvard, Lars Engebretsen, Ingrid Eitzen, and May Arna Risberg. “Functional Outcomes Following a Non-operative Treatment Algorithm for Anterior Cruciate Ligament Injuries in Skeletally Immature Children 12 Years and Younger. A Prospective Cohort with 2 Years Follow-up.” British Journal of Sports Medicine 47, no. 8 (May 2013): 488–494. doi:10.1136/bjsports-2012-092066.
• Moksnes, Håvard, Lars Engebretsen, and May Arna Risberg. “The Current Evidence for Treatment of ACL Injuries in Children Is Low: a Systematic Review.” The Journal of Bone and Joint Surgery. American Volume 94, no. 12 (June 20, 2012): 1112–1119. doi:10.2106/JBJS.K.00960.
• Moksnes, Håvard, Lynn Snyder-Mackler, and May Arna Risberg. “Individuals with an Anterior Cruciate Ligament-deficient Knee Classified as Noncopers May Be Candidates for Nonsurgical Rehabilitation.” The Journal of Orthopaedic and Sports Physical Therapy 38, no. 10 (October 2008): 586–595.
• Snyder-Mackler, Lynn, and May Arna Risberg. “Who Needs ACL Surgery? An Open Question.” The Journal of Orthopaedic and Sports Physical Therapy 41, no. 10 (October 2011): 706–707. doi:10.2519/jospt.2011.0108.
• Thorstensson, Carina A, L Stefan Lohmander, Richard B Frobell, Ewa M Roos, and Rachael Gooberman-Hill. “Choosing Surgery: Patients’ Preferences Within a Trial of Treatments for Anterior Cruciate Ligament Injury. A Qualitative Study.” BMC Musculoskeletal Disorders 10 (2009): 100. doi:10.1186/1471-2474-10-100.