---

Osteoarthritis Varus Knee: Mechanisms, Compartment Dynamics & Physiotherapy Rehabilitation

---

PART 1 - Pathomechanics of Varus Deformity in Knee OA

What is Varus Malalignment?

The Vicious Cycle

1. Medial cartilage loss → mechanical axis shifts further medially
2. Increased medial load → accelerated cartilage degradation
3. Subchondral bone sclerosis and collapse → further varus angulation
4. Progressive deformity → worsened load distribution

---

PART 2 - Compartment-by-Compartment Analysis

2.1 Medial Tibiofemoral Compartment - The Primary Victim

• In normal gait, approximately 60-70% of the total knee load passes through the medial compartment. In varus OA this rises to 70-90%.
• The key measure is the External Knee Adduction Moment (KAM) - the frontal-plane moment that attempts to adduct the knee during stance phase. This is the single best surrogate for medial compartment load.
• Static varus alignment increases the medial moment arm of the ground reaction force relative to the knee center, directly increasing the KAM.

• Progressive loss of medial articular cartilage (types II and X collagen degradation, proteoglycan loss)
• Subchondral bone sclerosis, then cyst formation, then collapse
• Medial tibial bone loss (>2-3 mm is a contraindication to osteotomy, per Campbell's)
• Medial meniscus extrusion and degeneration (the meniscus is progressively squeezed out of joint as varus worsens)
• Tightening of the medial collateral ligament complex in chronic varus

• A visible lateral snap/thrust of the knee during early stance, when the limb suddenly deviates into varus under body weight.
• Caused by weak hip abductors, lax medial structures, and elevated KAM.
• Associated with pain, stiffness, and disease progression independently of static alignment.
• Predicts cartilage loss in the medial compartment over time.

2.2 Lateral Tibiofemoral Compartment - Relatively Unloaded But Not Spared

• In varus OA the lateral compartment is unloaded or distracted during stance, not compressed.
• However, the lateral ligamentous structures (lateral collateral ligament, posterolateral corner) are placed under tensile strain as the knee "opens" laterally.
• Over time, lateral capsular and ligamentous laxity develops.
• The lateral femoral condyle may show osteochondral changes from abnormal kinematics and periodic impaction during loading.
• Important clinically: if lateral compartment narrowing develops on radiograph, this is a contraindication to high tibial osteotomy (per Campbell's Box 10.4), as the joint is now bicompartmental.

2.3 Patellofemoral Compartment

• Varus alignment alters the Q-angle (the quadriceps-to-patellar-tendon angle), typically reducing lateral patellar tilt.
• Quadriceps weakness - ubiquitous in knee OA - reduces the patellofemoral contact area and increases peak patellofemoral contact stress during stair-climbing and squatting.
• The patellofemoral compartment can be secondarily involved even when the primary disease is medial tibiofemoral.
• Trochlear groove geometry may be altered by altered loading patterns.

2.4 The Role of Hip Abductors and the Kinetic Chain

• Hip abductor weakness (particularly gluteus medius) allows the pelvis to drop toward the contralateral side during single-leg stance (Trendelenburg gait).
• This increases the lateral trunk lean toward the affected side, which paradoxically reduces KAM (a compensatory mechanism), but at the cost of hip OA risk and altered spinal mechanics.
• Hip abductor weakness has been independently associated with incident and worsening knee pain in medial OA (Frontiers Rehab Sciences, 2026).

2.5 Foot and Ankle Effects

• Subtalar pronation and medial foot arch collapse can increase tibial internal rotation, which propagates proximally to increase medial tibiofemoral loading.
• Achilles tendon thickness, navicular drop, and foot progression angle (FPA - the outward toe angle during walking) all modulate medial knee load.
• Lateral wedge insoles (raising the lateral heel 5-10°) shift the center of pressure laterally and reduce KAM by approximately 5-10%.

2.6 Neuromuscular and Proprioceptive Changes

• Joint mechanoreceptors (Ruffini endings, Pacinian corpuscles) in OA cartilage and synovium degenerate.
• Proprioceptive acuity decreases, especially frontal-plane joint position sense.
• Reduced proprioception → impaired muscle reaction time → failure to dynamically stabilize the knee against varus thrust → progression.
• Co-contraction of quadriceps and hamstrings (a stabilizing strategy) is impaired.

---

PART 3 - Role of Physiotherapy

Physiotherapy Targets in Varus OA:

---

PART 4 - Detailed Week-by-Week Rehabilitation Protocol

Setting: Outpatient physiotherapy, 3-5 sessions/week for the first 4 weeks then 2-3/week. Patient profile: Medial compartment OA with varus deformity, pain 4-7/10 VAS, preserved ROM but some restriction, no acute inflammatory flare, conservative management.

---

PHASE 1 - Pain Control and Baseline Restoration (Weeks 1-2)

Week 1

• TENS/Interferential current therapy: 20 min, 80-100 Hz, comfortable tingling, applied parapatellarly or medial joint line. Reduces acute pain and may reduce muscle inhibition.
• Cold therapy: Ice pack 10-15 min post-session if effusion present.
• Rest position education: Avoid prolonged knee flexion (>90°), avoid varus-loading postures (standing with crossed legs, heavy squatting).

• Supine heel slides: Active-assisted knee flexion/extension, 3 sets x 15 reps, pain-free range.
• Prone knee hangs: Gravity-assisted terminal extension, if flexion contracture present. 5 min x 2.
• Supine ankle pumps and quad sets: Maintain circulation, activate VMO. 3 x 20.

• Disease education: explain varus mechanics in simple terms - "the inner side of your knee is carrying more weight than it should."
• Activity modification: reduce high-impact activities, avoid kneeling on hard surfaces, use a walking stick in the contralateral hand (shifts mechanical axis, reduces medial load by ~10-15%).
• Weight management counseling if BMI >25 (each kg lost reduces knee load by ~3-4 kg per step).

• Quad sets (isometric): Knee fully extended on a rolled towel, tighten quadriceps, hold 10 sec. 3 x 10.
• SLR (straight leg raise): Supine, hip flexion with knee extended. 3 x 10 each direction (flexion, abduction, extension).
• Ankle alphabet: Maintain neuromuscular activity.

---

Week 2

• Patellar mobilizations: Superior, inferior, medial, lateral glides to restore full patellar mobility. Grade III-IV if stiffness present.
• Tibiofemoral joint mobilizations: Posterior tibial glide (AP) to restore knee extension. Grade II-III oscillations.
• Soft tissue techniques: ITB/lateral retinaculum release, medial hamstring stretching, calf stretching.

• Therapeutic ultrasound: 1 MHz, 1.0-1.5 W/cm², pulsed 20%, 5 min over medial joint line. Reduces subacute inflammation, promotes tissue extensibility.
• Alternatively: Low-level laser therapy (LLLT): 4J/cm² over 4 medial joint line points if available.

• Supine hip abduction: Side-lying or supine, 3 x 15. Critical for reducing varus thrust.
• Terminal knee extension (TKE) with resistance band: Standing, loop band behind knee, extend from 30° to full extension. 3 x 15. Targets VMO specifically.
• Seated leg press (low load): Machine or resistance band, 30-60° range only, avoiding full flexion. 3 x 12 at 40-50% perceived effort.

• Single-leg stance on firm surface: Affected limb, eyes open, 30 sec x 3. Focus on preventing knee "buckling" into varus.
• Weight shifting exercises: Standing with hands on wall, shift weight side to side. 3 x 10 reps.

• Assess for lateral wedge insoles (5° wedge, lateral heel) - prescribe if medial compartment OA with varus and no lateral compartment involvement.
• Assess footwear: motion control shoes reduce pronation-related tibial internal rotation.
• Consider valgus unloading knee brace referral if moderate-severe varus (>5°).

---

PHASE 2 - Strengthening and Neuromuscular Control (Weeks 3-6)

---

Weeks 3-4

• Stationary bike: 20 min, low resistance, comfortable cadence (70-80 rpm). Seat height set so knee reaches no more than 90° flexion. Promotes synovial fluid circulation and cartilage nutrition without high impact.
• Alternatively: Pool walking/hydrotherapy if available - water depth to waist reduces joint loading by ~50%.
• Target: mild breathlessness (Borg 11-13/20).

• Foot progression angle (FPA) modification: Teach patient to "toe out" slightly during walking (increase external foot rotation 5-10°). This reduces KAM by converting the ground reaction force to act more laterally. Evidence shows 5-10° increase in FPA can reduce KAM by 5-10%.
• Cadence training: Increase cadence (steps/min) by 10% using a metronome app (reduces impulse loading).
• Lateral trunk lean: Teach patient to lean slightly toward the affected side during stance phase - reduces KAM moment arm. Caution: excessive lean affects hip mechanics.
• Walking stick technique: Reinforce contralateral hand use at each session.

• Tibiofemoral anteroposterior and mediolateral mobilizations, Grade III-IV.
• Myofascial release: ITB, TFL, medial hamstrings.
• Neural tension techniques if sciatic or saphenous nerve involvement.

---

Weeks 5-6

---

PHASE 3 - Function, Endurance and Return to Activity (Weeks 7-10)

---

Weeks 7-8

• Progress all Phase 2 exercises by 10-15% load/repetitions.
• Introduce leg press single-leg: 3 x 10-12, 60-80% 1RM.
• Goblet squat: Full depth if comfortable, 3 x 10.
• Single-leg Romanian deadlift: 3 x 8-10 each side - challenges hip stability and prevents varus collapse.

• Treadmill gait analysis (if available): biofeedback for real-time gait metrics.
• Practice gait modifications (FPA, cadence, trunk lean) on varied surfaces (slopes, uneven terrain).
• Stair training: Adequate quad strength to descend stairs without knee-in collapse. Use handrail if needed. Eccentric quad loading is the key.

• Sit-to-stand from progressively lower chairs: 3 x 10 (quad + glute dominant).
• Functional reach tests: Standing balance with forward/lateral reach.
• Modified Timed Up and Go (TUG) practice: stand from chair, walk 3m, return. Target <12 sec.

• Pacing strategies: activity-rest cycle, "boom-bust" cycle avoidance.
• Flare management: ice, relative rest, continue gentle exercise.
• Long-term exercise prescription: minimum 150 min/week moderate aerobic + 2x resistance training (OARSI guidelines).
• Sleep hygiene, stress management (psychosocial factors modulate pain processing in OA).

---

Weeks 9-10

• 30-second Chair Stand Test (target >10 reps)
• 40m fast-paced walk test (target: reduced pain compared to baseline)
• Timed stair climb (target: >70% of age-matched norms)
• KOOS (Knee Injury and OA Outcome Score) reassessment

• Written, individualized home exercise program covering all key domains.
• Gym program with specific exercises if gym-goer.
• Hydrotherapy program if applicable.
• Cycling or swimming plan for aerobic conditioning.

• Lateral wedge insoles: review comfort and compliance. Adjust if needed.
• Valgus knee brace: review fit, usage pattern, functional benefit.

• 3-month telephone/telehealth review.
• Booster sessions as needed (1-2 sessions per 6 months is evidence-supported).
• Clear criteria for re-referral to orthopedics (persistent VAS >7/10 despite 3+ months of therapy, progressive varus, loss of ADL function).

---

PHASE 4 - Long-Term Maintenance (Months 3-6+)

---

Summary Reference Table: Weekly Progression at a Glance

---

Key Evidence Citations

• Campbell's Operative Orthopaedics, 15th Ed (2026) - varus biomechanics and compartment loading
• Lawford BJ et al. Exercise for osteoarthritis of the knee. Cochrane Database Syst Rev. 2024 Dec 3. [PMID 39625083] - confirms exercise reduces pain and improves function
• Yan L et al. Comparative efficacy of exercise modalities in knee OA. BMJ. 2025 Oct. [PMID 41093618] - network meta-analysis, tai chi and resistance training most effective
• Gibbs AJ et al. Recommendations for management of hip and knee OA. Osteoarthritis Cartilage. 2023. [PMID 37394226] - exercise universally recommended across all guidelines
• Frontiers Rehabilitation Sciences (2026) - Off-axis biomechanical alterations and interventions in medial knee OA: confirms KAM, varus thrust, FPA, step width as modifiable targets
• PMC 12399006 (2025) - Integrated rehabilitation framework for KOA: aerobic + resistance + biomechanical + education

---

Precautions in Varus Knee OA Physiotherapy Rehabilitation - With Rationale and Patient Education

---

DOMAIN 1 - Exercise-Related Precautions

---

1.1 Do Not Exercise Through Significant Pain (NRS >4/10)

• Pain signals active nociceptive input from joint structures. Exercising through severe pain triggers a neurological pain sensitization cascade - the dorsal horn neurons become progressively more excitable, lowering the pain threshold (central sensitization).
• High pain during exercise also inhibits quadriceps activation via arthrogenic muscle inhibition (AMI) - a reflex arc from joint afferents (primarily Ib inhibitory interneurons) that suppresses alpha motor neuron discharge to the quadriceps. This means if you force exercise through pain, the very muscles you are trying to strengthen become neurologically switched off.
• Repeated high-load painful exercise can increase synovial inflammation, elevate synovial fluid cytokines (IL-1β, TNF-α), and worsen cartilage degradation in the short term.

"A little discomfort during exercise is normal and expected - it means you are loading the joint. But sharp, severe, or worsening pain means the joint is being overloaded. Think of it like a blister: mild friction builds callus (adaptation), but too much tears the skin (damage). The '24-hour rule' is your guide: if your knee feels worse the next day than before you exercised, the dose was too high. Tell your therapist - we adjust the program, not stop it."

---

1.2 Avoid Deep Knee Flexion Early in Rehabilitation

• Tibiofemoral compressive force increases dramatically with flexion angle. At 90° knee flexion, the tibiofemoral contact force approximates 3-4x body weight. At full squat (>120°), this exceeds 7x body weight.
• In a varus knee, these compressive forces are disproportionately directed medially due to the altered mechanical axis.
• In the medial compartment where cartilage is already degraded, high compressive loads in flexion cause chondrocyte mechanotransduction-driven apoptosis and matrix metalloproteinase (MMP) upregulation - actively worsening cartilage loss.
• Patellofemoral joint stress also peaks at 60-90° flexion, risking secondary PFJ pain.

"Your knee is like a worn tire - the inner tread is thin. Bending your knee deeply puts enormous squashing force on exactly that worn area. In the early weeks, we keep the knee in a 'safe zone' of movement. As the muscles around the joint get stronger, they act as shock absorbers and take more of that force - then we can safely increase the range."

---

1.3 Avoid High-Impact Activities

• During running, the knee absorbs approximately 8x body weight per step. With 2,000+ steps per km, this represents enormous cumulative load on degraded articular cartilage.
• OA cartilage has lost its proteoglycan matrix (particularly aggrecan), reducing its compressive stiffness and hydraulic permeability. It cannot adequately redistribute impact forces, which are then transmitted directly to subchondral bone - causing bone edema (bone marrow lesions), microfractures, and pain.
• The absence of adequate quadriceps strength and neuromuscular control means the joint cannot dynamically absorb even moderate impact without varus collapse (thrust).

"Your cartilage is like the rubber sole on a worn-out shoe - it can still support you walking normally, but it cannot handle running on hard ground without wearing through faster. Swimming and cycling are actually better for your cartilage health because they keep the joint moving and the cartilage nourished without the pounding. We are not stopping you from being active - we are choosing the right activity for your joint."

---

1.4 The "Warm Up and Cool Down" Rule

• OA synovial fluid has altered viscoelastic properties - it is more viscous at rest (reduced lubrication). Gentle warm-up promotes synovial fluid distribution across the joint, reducing friction and improving articular cartilage nutrition through diffusion.
• Post-exercise cooling reduces reactive synovitis. Exercise-induced microtrauma to OA synovium can trigger an inflammatory response. Ice application (10-15 min) causes vasoconstriction, limits prostaglandin release, and reduces joint effusion formation.

"Think of your knee like an old door hinge - it needs oil and gentle movement before you push it hard. Starting cold and stopping abruptly causes more stiffness and soreness. The warm-up literally lubricates the joint. The ice after exercise limits the minor swelling that can build up."

---

1.5 Valgus Knee Alignment During All Exercises

• Every degree of varus alignment during exercise multiplies the medial compartment load. Allowing varus collapse during a squat or step-up creates a high-load, varus-moment impulse through the already-diseased medial cartilage.
• Technically, during an exercise like a step-down, varus knee collapse increases the external KAM by 15-25%, negating the therapeutic benefit and accelerating damage.
• Correct valgus tracking (knee over 2nd toe) shares load between medial and lateral compartments more evenly and trains the neuromuscular pattern for normal daily gait.

"When you exercise, watch your knee in a mirror or watch your shadow. Your kneecap should point forward over your second toe - not fall inward or bow outward. Every time your knee collapses inward or bows out during exercise, you are pressing down on the worn part of the joint with extra force. We train your muscles specifically to prevent this, but you need to consciously control it until it becomes automatic."

---

DOMAIN 2 - Biomechanical and Loading Precautions

---

2.1 Use a Walking Stick in the Contralateral Hand

• A contralateral cane creates a moment arm that reduces the hip abductor force required for single-leg stance on the affected side.
• This reduces the ground reaction force passing through the affected limb by approximately 10-20%, directly reducing KAM and medial compartment load.
• A cane on the ipsilateral side would require lateral trunk lean toward the affected side, which while also reducing KAM, creates asymmetric loading and is non-functional.

"It seems counterintuitive - you have pain in your right knee, so why hold the stick in your left hand? Think of it like a balance scale: the stick on the opposite side counterbalances your body weight, reducing how much force goes through your bad knee with every step. Holding it on the same side as the pain actually does very little for joint loading."

---

2.2 Lateral Wedge Insoles - Correct Use and Limits

• Lateral wedge insoles work by shifting the center of pressure laterally under the foot, reducing the valgus torque at the subtalar joint and the varus moment at the knee. This can reduce KAM by 5-10%.
• However, if lateral compartment OA is also present, the lateral shift of load will compress the lateral compartment - worsening that disease.
• Over-wedging (>7°) may cause lateral ankle pain, peroneal tendon strain, and discomfort.

"These insoles are working to tilt the force of the ground slightly away from the worn inner side of your knee. They need to be in the shoes you use most for walking. Check them every few months - if the foam is flattened or worn, they stop working. If you ever develop pain on the outer side of your knee or ankle with these insoles, stop wearing them and tell your therapist."

---

2.3 Body Weight Management

• Each kilogram of body weight generates approximately 3-4 kg of additional compressive force per step at the knee (due to the lever arm mechanics and muscle co-contraction needed to stabilize). Losing 5 kg therefore reduces the load on the knee by approximately 15-20 kg per step - over thousands of steps per day, this is clinically transformative.
• Adipose tissue is also metabolically active in OA - it secretes adipokines (leptin, adiponectin, resistin) that directly promote chondrocyte catabolism and synovial inflammation, independent of mechanical load.
• A 5-10% body weight reduction is the minimum threshold to achieve measurable pain and function benefits (Batayneh D et al., PMID 41316587, 2025).

"Every extra kilogram you carry puts roughly 3-4 kilograms of force on your knee with every step. Losing even 5 kilograms takes 15-20 kg of force off your knee - that is like removing a heavy backpack from your knee joint thousands of times a day. Your cartilage cannot regenerate, but you can dramatically slow the wear by reducing that load."

---

2.4 Avoid Prolonged Static Standing and Sustained Postures

• Articular cartilage is avascular and receives nutrition by diffusion from synovial fluid during joint movement. Prolonged static loading compresses the cartilage, squeezes out its interstitial fluid, and blocks diffusion of nutrients (glucose, oxygen) into the chondrocytes - causing chondrocyte hypoxia and matrix catabolism.
• Standing with legs crossed habitually forces the knee into an adducted (varus) posture, increasing medial compartment compressive stress chronically.

"Your cartilage is like a sponge - it needs movement to absorb nutrients from the joint fluid. Standing still for long periods squeezes the sponge dry and starves the cartilage. At work, aim to alternate sitting and standing every 20-30 minutes. Avoid crossing your legs when standing - it pushes the knee inward onto the worn part."

---

DOMAIN 3 - Red Flags and Assessment Precautions

"Osteoarthritis pain is usually a dull ache that builds with activity and eases with rest. If you ever have: a hot, rapidly swollen knee; fever; your knee 'locks' and you cannot straighten it; or you develop severe bone pain at night that wakes you up - these are different warning signs that need a doctor immediately, not just your exercises. Always tell your therapist if something new or different appears."

---

DOMAIN 4 - Psychological and Behavioral Precautions

---

4.1 Kinesiophobia (Fear of Movement)

• Kinesiophobia creates avoidance behavior → disuse → quadriceps atrophy → increased joint instability → increased pain → more fear. This "fear-avoidance cycle" is a major driver of disability in chronic knee OA.
• Pain science research (Hurley-Wallace AL et al., PMID 41275226, 2025 systematic review) shows that pain science education combined with exercise significantly outperforms exercise alone in reducing disability, because it modifies the catastrophizing cognition that drives avoidance.
• Psychosocial factors (depression, anxiety, pain catastrophizing) independently predict poorer functional outcomes in knee OA.

"Many people with OA develop a fear of moving because they associate movement with damage. This is understandable - but it is incorrect. Research shows very clearly that exercise does not damage OA knees, even when it causes some discomfort. In fact, the less you move, the weaker the muscles become, and the more your knee hurts. Pain during exercise does not equal damage - it is your sensitized nervous system being cautious. Movement is medicine for your joint."

---

4.2 Avoid the "Boom-Bust" Pattern

• Boom-bust creates unpredictable peaks of joint loading followed by rapid deconditioning. The cardiovascular and muscular systems do not adapt adequately to irregular, high-amplitude load spikes.
• Consistent submaximal activity drives the steady adaptive processes: muscle protein synthesis, cartilage matrix remodeling, bone adaptation, and neuromuscular habituation.
• Boom-bust also reinforces pain catastrophizing - each "bust" day confirms the patient's belief that activity is dangerous.

"On a good day, do not 'bank' all your activity - trying to do everything in one day will trigger a painful flare the next day that sets you back. On a bad day, do not stop all activity either. Think of it like a bank account: make small, regular deposits rather than one big one followed by nothing. Steady moderate activity every day is far better than occasional bursts."

---

4.3 Compliance and Long-Term Adherence

• Exercise-induced neurochemical changes (endorphin release, reduced central sensitization, muscle hypertrophy) are time-limited adaptations that reverse with deconditioning.
• Behaviorally-based self-management programs (goal setting, self-monitoring, social support) produce significantly better long-term outcomes than instruction-only programs (Rheumatology textbook evidence, Elsevier 2022).
• ACR guidelines explicitly recommend self-management programs for OA.

"Physiotherapy is not a passive treatment like a medication - it only works while you are doing it. The exercises must become a permanent part of your life, like brushing your teeth. Set specific times in your day for your program. Start with 10 minutes and build up. Your muscle strength will maintain your joint protection - but only for as long as you keep training."

---

DOMAIN 5 - Adjunctive Therapy and Equipment Precautions

---

Summary Patient Education Framework - "The 5 Pillars"

---

---

Shifting Load from Medial to Lateral Compartment: Exercises, Strategies and the Valgus Brace

---

SECTION 1 - Understanding the Problem First

KAM = GRF × (perpendicular distance from the GRF vector to the knee joint center)

---

SECTION 2 - Exercises and Movement Strategies That Shift Load Medial → Lateral

---

GROUP A - Gait Modification Techniques

---

A1. Foot Progression Angle (FPA) Increase - "Toe-Out Gait"

• Toeing out externally rotates the tibia and shifts the GRF line laterally relative to the knee center.
• This reduces the perpendicular distance between the GRF and the knee - directly shrinking the KAM.
• Studies show a 5-10° increase in FPA reduces KAM by approximately 5-10% - clinically meaningful over thousands of steps.

• Stand in front of a mirror. Place tape in a "V" shape on the floor at your target angle.
• Walk along the tape lines, ensuring both feet follow the toe-out pattern.
• Practice 10 minutes daily until it becomes automatic.
• Progress to treadmill walking at the modified angle, then to outdoor surfaces.

---

A2. Lateral Trunk Lean - "Ipsilateral Lean Gait"

• Leaning the trunk toward the affected limb moves the body's center of mass (COM) closer to the stance foot.
• This shortens the horizontal distance between the COM and the knee joint - reducing the frontal-plane moment arm of body weight that drives the KAM.
• Studies (Hunt MA et al., 2008; Simic M et al., 2012) show that increasing ipsilateral trunk lean significantly reduces the KAM, with each additional 5° of lean producing measurable load reduction.
• A lean of 5-10° can reduce KAM by 10-20% in some patients.

• Walk in front of a mirror. As the right foot (affected side) hits the ground, gently shift the right shoulder slightly down and toward the right.
• The movement is subtle - not a full side-bend, just a gentle shift of the upper body weight.
• Practice with a therapist giving feedback first; later use a mirror or video on a phone.

---

A3. Increased Step Width - "Wide-Base Walking"

• A wider step places the foot more laterally relative to the hip, shifting the GRF line laterally and reducing the adduction moment at the knee.
• This is the most natural and lowest-energy of the gait modifications.
• A systematic review (Wang Y et al., Sports Med Open 2024) confirmed step width modulates frontal-plane knee loading during locomotion.

• Place two parallel strips of tape on the floor about 30-40 cm apart (hip-width).
• Walk with each foot on or just outside each tape strip.
• Practice both on the treadmill and on flat ground.
• Progress to varying surfaces.

---

A4. Medial Knee Thrust Technique

• Shifting the knee medially during loading moves the joint center closer to the GRF line, reducing the moment arm and thus the KAM.
• Research shows acute KAM reductions of up to 20% with practiced medial thrust gait.

• As the foot strikes the ground, consciously push the kneecap slightly inward (toward the other leg) as weight is accepted.
• This is a subtle movement, not a dramatic shift.
• Typically taught with gait analysis or mirror feedback.

---

A5. Reduced Stride Length / Increased Cadence

• Shorter strides reduce the peak vertical GRF per step and reduce the peak knee flexion angle at midstance - both of which reduce the peak KAM.
• Increasing cadence by 10% above comfortable walking speed has been shown to reduce both the KAM and the knee flexion moment simultaneously.

• Use a free metronome app on the phone. Set it 10% faster than your current comfortable walking rate.
• Walk to the beat, taking slightly shorter, quicker steps.
• Start on a flat surface for 10 minutes. Progress to 20-30 minutes.

---

GROUP B - Strengthening Exercises That Reduce Medial Load

---

B1. Hip Abductor Strengthening (The Most Important Group)

---

B2. Quadriceps Eccentric and Isometric Training

---

B3. Hip External Rotator Strengthening

---

B4. Core and Lumbopelvic Stability

• Dead bug: Supine, arms to ceiling, alternate lowering arm and opposite leg. 3 x 8-10.
• Bird dog: Quadruped, extend opposite arm and leg. 3 x 10 each side.
• Side plank: 20-30 sec holds, 3 sets.
• Pallof press (anti-rotation): Resistance band at chest height, press forward and hold; resists trunk rotation.

---

B5. Foot and Ankle Exercises (Distal Control)

---

GROUP C - Postural and Positional Strategies in Daily Life

---

SECTION 3 - The Valgus Unloader Knee Brace: Complete Guide

---

3.1 What Is It and What Does It Do?

---

3.2 The Three-Point Bending Mechanism - How It Works

VALGUS BRACE - THREE-POINT FORCE DIAGRAM

     THIGH CUFF ──────────────── FORCE F2 (medially directed)
                                      ↓
     DYNAMIC STRAP ──────────── FORCE F1 (laterally directed, at joint level)
                                      ↑
     TIBIAL CUFF ─────────────── FORCE F3 (medially directed)

• F1 (dynamic strap, at joint line level): Pushes the knee laterally at the joint level. This is the primary corrective force. In a varus knee, this pushes the medially deviated knee back toward a neutral or slightly valgus position.
• F2 (thigh cuff, above joint): Pushes the thigh medially (opposite direction).
• F3 (tibial cuff, below joint): Pushes the tibia medially (opposite direction).

---

3.3 Biomechanical Effect: What Changes?

---

3.4 Types of Valgus Unloader Braces

---

3.5 How to Fit and Apply the Brace - Step-by-Step

Fitting (Done by orthotist or trained physiotherapist):

1. Measure the limb: Thigh circumference at mid-thigh, calf circumference at largest point, and the distance from the joint line to the tibial tubercle.
2. Set the valgus correction angle: Typically 4-8° for mild-moderate varus. The angle is set at the hinge. More than 8° correction is rarely used as it increases lateral compartment load.
3. Trial and check: Patient walks 50 meters. Check for migration (brace sliding down), pressure areas, and symptom response.

Daily Application (Patient instruction):

1. Step 1 - Sit down. Always apply and remove the brace while seated with the knee at 90°.
2. Step 2 - Check the skin. Inspect for any redness, sores, or wounds before application.
3. Step 3 - Position the hinge. The lateral hinge must align with the lateral knee joint line (the space between the femur and fibular head). This is the most important step - incorrect hinge placement means incorrect force direction.
4. Step 4 - Secure the thigh cuff first. Apply the upper (thigh) strap first, moderately snug. You should be able to slide one finger under it.
5. Step 5 - Secure the tibial cuff. Apply the lower (calf) strap, same firmness.
6. Step 6 - Apply the dynamic strap/corrective force. Tighten the corrective strap or dial to the prescribed setting. This applies F1. Start at a moderate tension and increase over 1-2 weeks as tolerated.
7. Step 7 - Check alignment. Stand and confirm the kneecap is facing forward, the brace has not rotated, and the hinge aligns with the joint line.
8. Step 8 - Walk a few steps. Confirm no pain under straps, no numbness distally.

---

3.6 Daily Use Schedule

---

3.7 Practical Daily Life Guidance

---

3.8 Limitations of the Valgus Brace

---

Summary: How Each Strategy Works at a Glance

---