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!

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