This document discusses genu varum (bow legs) and genu valgum (knock knees) in children. Genu varum is caused by lateral angulation of the knee with the femur and tibia deviating medially, while genu valgum involves medial angulation with outward deviation. Clinical features, assessment methods like the intercondylar/intermalleolar distance and plumb line tests, and treatment options like epiphyseal stapling and osteotomies are described for both conditions. Blount's disease, which causes abnormal proximal tibial growth, is also summarized.

1. BINISHA SEBBY
Dr SMCSI MC
Karakonam

2. ANATOMIC AXIS
OF FEMUR
ANATOMIC AXIS
OF TIBIA
(5-7degree)
Normal knee is
approximately 6° valgus

3. PHYSIOLOGICAL
Bow legs &
Knock knees
 Considered as normal stages of development
 Usually disappears when child grows ,around 7-8 yrs
 By age of 10 , still marked – Operative correction
 Stapling of physes
 Corrective osteotomy
 Hemi epiphysiodesis

4. GENU VARUM
 Lateral angulation of the
knee with longitudinal axis
of both tibia and femur
deviating medially.
 Also called as BOW LEGS

5. E
T
I
O
L
O
G
Y
UNILATERAL BILATERAL
Growth abnormalities of upper tibial epiphysis Congenital causes
Infections like osteomyelitis Postural abnormalities
Trauma near growth epiphysis of femur Developmental disorders
Tumour affecting lower end of femur &
upper end of tibia
Metabolic disorders(rickets)& Endocrine
disorders
Degenerative disorders (Osteoarthritis of
knee)
Occupational disorders
Idiopathic
Paget’s disease
Blounts disease ( tibia vara)

6. BLOUNTS DISEASE
Abnormal growth of posteromedial part of proximal tibia
Growth plate near the inside of the knee either slow down
or stop making new bone.
Children usually over weight & early walkers
Ugly deformity - complaint
Spontaneous resolution rare

7. X RAY
Proximal tibial epiphysis flattened medially
Adjacent metaphysis beak shaped
TREATMENT
 Corrective osteotomy
 Hemi epiphysiodesis

8. CLINICAL FEATURES
PRIMARY DEFORMITY SECONDARY DEFORMITY
Lateral angulation of knee Internal torsion of distal tibia
In toeing of both feet
Patella face outward while walking
Tight medial & lax lateral structures

9. CLINICAL ASSESSMENT
 INTERCONDYLAR DISTANCE
Distance between knees with child standing and
heels touching
Normal : < 6 cm
Genu Varum - Increased

10. PLUMB LINE TEST
 Normally a line drawn from ASIS
to middle of patella, if extyended
down strikes the medial malleolus
 GENU VARUM: Medial malleolus
will be medial to this line

11. TREATMENT
Lateral epiphyseal stapling

12. Lateral closing wedge osteotomy Medial opening wege osteotomy
OSTEOTOMY

13. GENU VALGUM
 Medial angulation of knee
with outward deviation of
longitudinal axis of both tibia
and femur
Also called as KNOCK KNEE

14. UNILATERAL BILATERAL
Trauma Congenital disorders
Osteomyelitis Idiopathic
Tumors Developmental disorders(eg. Epiphyseal dysplasia)
Endocrine disorders(eg. Thyroid disorders)
Metabolic disorders(eg. Rickets)
Paralytic disorders
Traumatic disorders
Infective disorders
Inflammatory disorders(Rheumatoid arthritis)
Degenerative disorders
E
T
I
O
L
O
G
Y

15. CLINICAL FEATURES
PRIMARY DEFORMITY SECONDARY DEFORMITY
Medial angulation of knee Distal end of femur & proximal tibia
rotated externally
Compensatory internal torsion of distal
tibia
Lateral dislocation of patella
Tight lateral & lax medial structures
Flat foot

16. CLINICAL ASSESSMENT
 INTERMALLEOLAR GAP
Distance between the 2 medial malleoli
when knees are lightly touching and
patella facing forwards.
Normal : <8 cm
Genu valgum – Increased, >10 cm

17. PLUMB LINE TEST
 Normally a line drawn from ASIS
to middle of patella, if extyended
down strikes the medial malleolus
 GENU VALGUM: Medial malleolus
will be lateral to this line

18. Q ANGLE
 Angle formed between Quadriceps muscle
and patellar tendon
 Draw a line from ASIS to the midpoint of
patella and then from the midpoint of the
patella to the tibial tubercle. Angle formed
between.
 Normal Males – 14 degree
Females – 17 degree
 Genu Valgum – Increased Q angle

19. TREATMENT MILD (Around 4 years)
Medial heel raise Knock knee braces Medial epiphyseal stapling

20. Severe ( > 10 cm IM at 10 years )
OSTEOTOMY
Medial Closing wedge osteotomy Lateral Opening wedge Osteotomy