You’re in the middle of a re-evaluation when you notice your patient’s knees bowing outward as they walk. This isn’t just a quirk of their stance; it’s a classic presentation of genu varum, and understanding its implications is key to directing your entire Plan of Care.
What is Genu Varum?
Genu varum (JEE-no VAY-rum), commonly known as “bow-leggedness,” is a lower extremity alignment condition characterized by a lateral angulation of the tibia relative to the femur. This results in a distinct bowing of the knees, leaving a visible gap between the medial knee joints when the feet are together. It’s the opposite of genu valgum (knock-knees). While some degree is normal in infants, persistent genu varum in adults is often a sign of underlying joint or bony issues.
Why Genu Varum Matters in Physical Therapy Practice
This alignment significantly alters the mechanical axis of the lower limb, shifting the body’s weight-bearing line medially to the knee joint. This places excessive, concentrated stress on the medial meniscus and the medial compartment of the knee. Over time, this increased joint reaction force is a primary contributor to medial knee osteoarthritis. Your role is to recognize this biomechanical stressor and address modifiable factors—like muscle weakness and tightness—to help slow disease progression and manage pain.
What You’ll See in the Clinic
Patients may report medial knee pain that worsens with weight-bearing activities like walking, stair climbing, or running. On observation, you’ll see the characteristic bowing. You may also note compensatory overpronation of the feet and potential lateral hip weakness. A key finding is often a positive varus stress test, indicating potential laxity in the lateral collateral ligament (LCL).
“Initial eval: Patient is a 58-year-old male with 6/10 medial knee pain. Observation reveals bilateral genu varum. Gait analysis shows decreased stance time on the left and notable foot overpronation. Medial joint line tenderness is present. Plan: Initiate quadriceps and hip abductor strengthening, along with manual therapy to address lateral knee soft tissue tightness.”
Common Pitfall & Pro Tip
⚠️ Pitfall: Focusing solely on the knee. Genu varum is a lower-extremity alignment issue. If you ignore the foot and hip, you’re missing half the equation. Assess for overpronation and hip abductor weakness, as these can exacerbate the stress on the medial knee.
💡 Pro Tip: For patients with symptomatic genu varum, consider a trial of a lateral heel wedge or recommend a referral for an orthotic evaluation. This simple intervention can help shift the ground reaction force laterally, potentially reducing medial knee loading by a significant amount.
Memory Aid for Genu Varum
Think of the letter “O”. The legs form an “O” shape with a space between the knees. The “O” can stand for “Outward”—the knees are pushed outward, away from the midline. This simple visual is a quick way to recall the condition and differentiate it from the “X” shape of genu valgum.
NPTE Connection
Expect to see genu varum in questions related to gait deviations, knee osteoarthritis, and special tests. You’ll need to identify the condition from a description or image and know which structures are at risk for injury or degeneration.
Related Physical Therapy Concepts
Genu varum is intimately connected to Knee Osteoarthritis, as it is a major risk factor for medial compartment wear. It also relates to the assessment of Genu Recurvatum (hyperextension of the knee), which can present in combination. Additionally, understanding Ankle Pronation is crucial, as it is a common compensation that can either worsen or mitigate the forces at the knee.
Quick Reference
✓ Key values/findings: Normal alignment is 0-4° valgus; >4° varus is considered abnormal ✓ Priority level: High – A primary risk factor for medial knee OA ✓ PT Interventions/Considerations: • Strengthen quadriceps, hip abductors, and core • Stretch lateral knee structures (IT band, lateral hamstring) • Gait training with cues for foot progression angle • Consider orthotic referral for lateral heel wedge • Patient education on joint protection and activity modification • Assess for LCL laxity (varus stress test)
Bottom line: Recognizing genu varum is the first step to protecting your patient’s medial knee compartment and keeping them moving for years to come.