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PATELLOFEMORAL PAIN SYNDROMEMATTHEW REYNOLDS
OXFORD BROOKES UNIVERSITY
WHY PFPS?
• Two patients with PFPS
• Initial unsuccessful treatments
• Very little knowledge of condition
• Vast/ unspecific understanding of causes
• Two podcasts Got me interested!
CASE STUDY INTRODUCTION – HOW DID THEY PRESENT?▪ 34 y/o lady
▪ Referred with 4 year history of left knee pain huge walk
▪ MRI = ? Patellar tendon impingement + Minor chondral degeneration
▪ Body Chart: 8/10 Lateroinferior Left Knee Pain (No neural involvement)
▪ Aggs: Hiking, Running, Prolonged Sitting, Driving
▪ Eases: Rest
▪ SH: Very active! Hiking 2/7, Walking, Therapeutic Care Worker
▪ Obs: TOP infrapatellar fat pad, patella maltracking laterally
▪ ROM: Knee = Full / PFJ = Reduced medial glide, P1
▪ Joint: Intact ligaments and meniscus, +ve Hoffa’s test
▪ Strength: 4/5 Knee Ext, P1 EOR
WHAT I DID INITIALLY?
▪ Clinical Impression:▪ Anterior Knee Pain secondary to Infrapatellar Fat Pad Impingement
▪ Treatment:▪ Initial:
▪ Advice on pacing▪ Advice on activity choice (cycling, swimming)▪ HEP = Wall Squat
• Umbrella term for all peripatellar or retropatellar pain
• Also referred to as:• Runners Knee• Patellofemoral Joint Syndrome• Chondromalacia Patellae• Anterior Knee Pain
• Numerous PFJ structures are susceptible to overload:• Peripatellar Synovitis• Lateral Retinaculum • Infrapatellar Fat Pad• Medial Patellofemoral Ligament
• May predispose to the development of Patellofemoral Osteoarthritis
WHAT IS PATELLOFEMORAL PAIN SYNDROME (PFPS)?
= potent sources of noxious input
(Dye, 2005; Fithian, Powers, and Khan, 2010; Luhmann et al., 2008; Post, 2016)
PFPS PRESENTATION• Accounts for 11-17% of all knee pain
presentations to GP
• Typically physically active young adults <40 years• Adolescences = Periods of rapid growth• Older Adults = Degenerative changes in PFJ
• Women > Men
• Vicious Cycle:• Pain• Inactivity• Weight Gain• Increased PFJ Loading• Increased Pain
▪ Common Symptoms:• Gradual onset diffuse anterior knee pain• Associated with increased frequency or duration of
PFJ loading activities:• Squatting• Ascending/ Descending Stairs• Prolonged Sitting (‘Movie Gowers Knee’)• Hiking• Running
• Rarely pain when PFJ is unloaded:• Sleeping• Standing• Resting
• Crepitus• NO locking or giving way, minimal swelling• Stiffness, but FULL ROM
(Crossley, Callaghan, and van Linschoten, 2015; Duncan et al., 2006; Hinman et al., 2014)
DIAGNOSIS▪ Primarily based on symptom identification
▪ No definitive clinical test!▪ Best option = Anterior Knee Pain elicited during a functional squat▪ TOP of patellar edges
▪ Limited evidence for imaging
▪ Differential Diagnosis:▪ Patellar Tendinopathy▪ Osgood Schlatter disease▪ Ligament Sprains/ Ruptures▪ Patellar Dislocation▪ Meniscal Tears▪ Patellar Subluxation or Instability▪ RA
(Nunes et al., 2013)
FUNCTIONAL ANATOMY• Full Extension = Patella sits lateral to trochlea
• During Flexion = Patella moves medially, when laterally again
• Actively controlled by:o VMOo Vastus Lateralis
• Increasing knee flexion = Greater articular surface contact area
• PFJ Loads:• Level Walking = 1.5 times body weight• Ascending Stairs = 3.3 times body weight• Running = 5.6 times body weight• Squatting = 7.5 times body weight
• ABNORMAL ALIGNMENT AND TRACKING = INCREASED OR UNACUSTOMED LOADS = PATELLOFEMORAL PAIN!
(Baheti and Jamati , 2016; Brukner and Khan, 2012; Fulkerson et al., 2004; Wung, 2009)
MY RESEARCH AND THE FINDINGS
PAIN PREDISPOSING FACTORS AND IDENTIFICATION
Increased or Unaccustomed
PFJ Loads
Abnormal Alignment or
Tracking
Extrinsic Factors
LOCAL Intrinsic Factors
REMOTE Intrinsic Factors
Ground Force
Reaction
Increase in Flexion
Activities
Increased Femoral IR
Increased Apparent
Knee Valgus
Increased Tibial
Rotation
Pronated Foot Type
Inadequate Flexibility
Vasti Neuromuscular
Control
Patellar Position
Soft Tissue ContributionsPFPS
REMOTE INTRINSIC FACTORS
Increased Femoral IR
StructuralFemoral
Anteversion
Inadequate Strength
Hip ERs and Abds
Altered Neuromotor
ControlHip ERs and Abds
ROM DeficitsHip
(Boling et al., 2009; Plastaras et al., 2015)
REMOTE INTRINSIC FACTORS
Increased Knee
Valgus
Structural- Genu, Tibial, Coxa
Valgum- Increased Q Angle
Inadequate Strength
- Hip ERs and Abds- Quads + Hammy’s
Altered Neuromotor Control
- Hip ERs and Abds- Lumbopelvic
ROM DeficitsHip
(Barton et al., 2009; Esculier et al., 2015; Messier et al., 1991; Myer et al., 2010)
- Increased Q Angle- Increased Hip
Adduction- Increased Knee
Abduction
REMOTE INTRINSIC FACTORS
Increased Tibial
Rotation
Femoral Rotations
Subtalar MotionNot in
isolation. Rather caused
by these:
REMOTE INTRINSIC FACTORS
Pronated Foot Type
(Boling et al., 2009)
REMOTE INTRINSIC FACTORS
Inadequate Flexibility
Quadriceps- Rectus Femoris
Hamstrings
TFL / ITB
Gastrocnemius
(Patil et al., 2010; Witvrouw et al., 2000)
LOCAL INTRINSIC FACTORS
Patellar Position
Lateral Displacement
Lateral Tilt
Rotation
Posterior Tilt
LOCAL INTRINSIC FACTORS
Soft Tissue Contributions
Tight Lateral Structures
Overall Hypermobility
Compliant Medial Structures
(Witvrouw et al., 2000)
LOCAL INTRINSIC FACTORS
Vasti Neuromuscular
Control
Reduced Activity of Quads
Delayed Onset of VMO
Altered Reflex Response
Delayed Onset of VL
(Van Tiggelen et al., 2009; Witvrouw et al., 2000)
SUMMARYRISK FACTORS
▪ Increased Femoral IR
▪ Increased Knee Abduction Moment
▪ Pronated Foot Type
▪ Decreased Quads Flexibility
▪ Patellar Hypermobility
▪ Tight Lateral Structures (ITB and Lateral Retinaculum)
▪ Decreased VMO Strength
▪ Decreased VMO / VL Synchronisation
NOT RISK FACTORS▪ Q Angle
▪ Increased Hip Adduction (alone)
▪ Increased Tibial Rotation (alone)
▪ Decreased Hamstring Flexibility
REHABILITATION GOALSAcute:
1. Immediate symptom reduction
Rehabilitation:
2. Identify the cause:▪ Extrinsic▪ Intrinsic
3. Rehab the cause
4. Gradually ‘reload’ PFJ and return to normal function
Gradual ‘Reloading’ of PFJ and Return
to Normal Function
Identify and
Rehab Cause
OFFLOAD REHAB RELOAD(Collins et al., 2013; Witvrouw et al., 2014)
1. IMMEDIATE SYMPTOM REDUCTION▪ True rest
▪ Pacing
▪ Pain Relief – Ice / Heat / Medication▪ Only masks further damage!
▪ Taping
▪Mobilisations McConnell’s technique
Medial Tilt technique (Aminaka and Gribble, 2005; Chang et al., 2015; Crossley et al., 2015; Wilson et al., 2003)
2-3. IDENTIFY AND REHAB THE CAUSE
▪ Identification =▪ Risk Factor Understanding▪ Subjective/ Objective Assessment
▪Multimodal Physio Rehab Program:▪ Training Error▪ Muscle Weakness▪ Poor Motor Control▪ Decreased Flexibility▪ Abnormal Biomechanics
(Collins et al., 2012)
TRAINING ERROR▪ Extrinsic factors:▪ Changes in:▪ Body Mass▪ Training/ Activity Workload:
▪ Speed of Gait▪ Surfaces▪ Frequency▪ Quality▪ Footwear
▪ Graded return as rehab progresses
Extrinsic Factors
Ground Force Reaction
Increase in Flexion Activities
MUSCLE WEAKNESS▪ Biggest evidence base!
▪ (Pain Free) Strengthening of:▪ Knee Extensors – Quads, VMO▪ Hip External Rotators and Abductors – Glute Med
▪ Closed Chain = Open Chain▪ Closed Chain = 0-45 degrees range▪ Open Chain = 90-50 degrees + 20-0 degrees ranges
▪ Open Chain:▪ Quads = Static Quads, IRQ, SLR▪ Glute Med = Side Lying Abduction, Side Plank Abduction, Clam
▪ Closed Chain:▪ Single-Leg Squat, Shallow Knee Dip, Lateral Band Walks
▪ Hamstrings and Quads = POWER▪ 10 reps / 3 sets / Large Resistance / 2 min Rest Periods
▪ Glutes = ENDURANCE▪ 15-25 reps / 3-5 sets / Large Resistance / 1-2 min Rest Periods
(Alba-Martín et al., 2015; American College of Sports Medicine, 2009; Boren et al., 2011; Clijsen et al., 2014; Distefano et al., 2009; McBeth et al., 2012; Santos et al., 2015; van der Heijden et al., 2015)
POOR MOVEMENT CONTROL▪ Hip Function and Vasti Retraining
▪ Taping Techniques
▪ Single Leg Stand (10-20 secs, 10-15 sets):▪ SLS▪ SLS Eyes Closed▪ SLS with Bilateral Trunk Side Flexion▪ SLS with Forward/ Backward Leaning▪ SLS with Balance Boards/ Cushions
▪ Single Leg Dip (10-15 reps, Good Quality Movements):▪ Shallow (30-40 degrees) Single Leg Dip▪ Deep Single Leg Dip▪ Single Leg Dip with Trunk Flexion▪ Single Leg Dip with Weights▪ Single Leg Dip with Balance Boards/ Cushions▪ Single Leg Dip (Bum Tap)
(Cowan et al., 2002; Crossley et al., 2002; Davis and Powers, 2010; Goom, 2012a; Goom, 2012b))
REDUCED FLEXIBILITY▪ Goal = Improving compliance
▪ Stretches and Foam Roller:▪ Hip Flexors▪ Quads▪ ITB▪ Hamstrings▪ Gastrocnemius
ABNORMAL BIOMECHANICS▪ Goal = Reducing the PFJ load
▪ Orthotics
▪ Taping
▪ Strengthening
▪ Motor Control
▪ Flexibility
(Collins et al., 2009; Smith et al., 2015)
4. GRADUAL ‘RELOADING’ AND RETURN TO FUNCTION
(Dye, 2005; Goom, 2012c)
Normal
Injured
Post Rehab
Envelope of Function = ‘the function of a
mechanical transmission, defined by the torque that can
be safely withstood and transmitted by that system without
damage
What have I learnt?
What would I do differently?
SELF REFLECTION
What have I learnt?
• What causes a more likely
• What structures are likely producing pain
• How to structure my rehab
• Best treatment choices = Multimodal!
• The importance of explanation!
What would I do differently?
• Structure my objective assessment to identify cause
• Focus first on pain relief and explaining importance of unloading the PFJ
• Use correct taping technique early to aid offloading
• Use mobilisations to affect local extrinsic factors
• Focus on VMO and Glute Med Rehab, Motor Control
• Using Open Chain if Closed Chain produces pain Working in range of least PFJ loading
ANY QUESTIONS
THANK YOU!
REFERENCES▪ Alba-Martín, P., Gallego-Izquierdo, T., Plaza-Manzano, G., Romero-Franco, N., Núñez-Nagy, S. and Pecos-Martín, D. (2015) ‘Effectiveness of therapeutic physical
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▪ Baheti, N.D. and Jamati , M.K. (eds.) (2016) Physical Therapy: Treatment of Common Orthopedic Conditions. 1st edn. India: Jaypee Brothers Medical Publishers.
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▪ Boling, M.C., Padua, D.A., Marshall, S.W., Guskiewicz, K., Pyne, S. and Beutler, A. (2009) ‘A prospective investigation of biomechanical risk factors for patellofemoral pain syndrome: The joint undertaking to monitor and prevent ACL injury (JUMP-ACL) cohort’, The American Journal of Sports Medicine, 37(11), pp. 2108–2116. doi: 10.1177/0363546509337934.
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▪ Collins, N.J., Bisset, L.M., Crossley, K.M. and Vicenzino, B. (2012) ‘Efficacy of nonsurgical interventions for anterior knee pain: systematic review and meta-analysis of randomised trials’, Sports Medicine, 42(1), pp. 31–49. doi: 10.2165/11594460-000000000-00000.
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