McG 32: Juvenile HAV

Question 1

what is the incidence of HAV in adolescence

Answer 1

22-36%

Question 2

is juvenile HAV more common in M or F

Answer 2

F

Question 3

what percent of HAV occur b/l in females

Answer 3

75%

Question 4

extrinsic factors

Answer 4

• tight or pointed shoes

- higher in the shod population than barefoot

Question 5

intrinsic factors

Answer 5

-family hx (58-50%)

Question 6

who is 5x more likely to develop HAV

Answer 6

black children

Question 7

types of juvenile HAV

Answer 7

• congenital
• neurogenic
• idiopathic

Question 8

what is Roots theory for causes of HAV

Answer 8

• the causative factor for all hallux HAV deformity is mechanical malfunction of the 1st MTPJ
• ex. factors that increase STJ pronation and instability of the 1st ray will enhance the progression of the hallux valgus deformity

Question 9

what did Lapidus believe was the cause of HAV deformity

Answer 9

-instability of the medial column

Question 10

what percent of adolescents with HAV had an abnormally high MAA

Answer 10

75%

Question 11

what does an increase in PASA indicate

Answer 11

an increase in PASA indicates functional adaptation of the 1st MT due to chronic malpositioning of and abnormal faces on the great toe

Question 12

how do you measure PASA

Answer 12

relationship between a line connecting the medial and lateral articular margins of the 1st MT head and the longitudinal axis of the 1st MT

Question 13

normal PASA

Answer 13

0-8 degrees

Question 14

how do you measure MAA on DP projection

Answer 14

angle formed between the line bisecting the 2nd MT and the longitudinal line bisection of the lesser tarsus

Question 15

normal MAA

Answer 15

5-17; patological ~20

Question 16

how do you calculate the true/effective IMA

Answer 16

IMA + (MAA-15)

Question 17

what neurological disorder can lead to HAV

Answer 17

cerebral palsy - produce spasticity or contractors of the AT

Question 18

what other factors can contribute to HAV in adolescence

Answer 18

• LLD
• torsional abnormalities
• neuromuscular disease
• MAA
• pes planovalgus

Question 19

track bound joint indicates a deviation of the 1st MTPJ which is associated with what increased angle

Answer 19

PASA

Question 20

relative contraindication to surgery

Answer 20

• ligamentous laxity
• hyper-elasticity
• neuromuscular disorders

Question 21

goals of surgery

Answer 21

relieve pain, restore proper jt function, prevent progression of the deformity improve cosmesis

Question 22

factors to consider

Answer 22

• age of pt
• growth plate status (open or close)
• presence of coexisting etiologies
• age of onset and progression of the deformity
• family hx
• degree of symptomatology - psychological and physical
• pt and parent expectations

Question 23

what age should sx be performed

Answer 23

11-15

Question 24

surgical options

Answer 24

• base of head osteotomies
• soft tissue procedures
• hallux osteotomies
• epiphysiodesis

Question 25

List type 1 HAV characteristics

Answer 25

- earlier onset - greater familial hx - MA - severe deforming forces such as pes planovalgus/equinus

Question 26

T or F: Type 1 HAV individuals would benefit from early surgical intervention

Answer 26

T

Question 27

list type 2 HAV characteristics

Answer 27

- pts w/ moderate deformity (IM, HAA) - rectus foot type - controllable deforming forces

Question 28

when should sx be performed in type 2 HAV

Answer 28

when skeletal maturity has been achieved

Question 29

goal of ST procedures

Answer 29

relocate the sesamoid apparatus beneath the 1st MT by aligning the FHL tendon allowing proper sagittal plane motion of the hallux

Question 30

name additional ST procedures

Answer 30

lateral capsulotomy medial capsulorrhaphy transfer of the adductor tendon

Question 31

name distal MT osteotomies for juvenile HAV

Answer 31

-autin, offset V, reversion, mitchell, wilson, peabody

Question 32

MT head osteotomies can reduce the IMA by how much

Answer 32

13.3

Question 33

complications of Mitchell and Wilson osteotomies

Answer 33

shortening transfer lesions elevates metatarsalgia

Question 34

when are transpositional osteotomies performed

Answer 34

when pts have a rectus foot and moderate IMA

Question 35

name proximal osteotomies

Answer 35

closing or opening base wedge osteotomy crescentic procedures Lapidus

Question 36

when are proximal osteotomies performed

Answer 36

IMA 15 degrees or greater

Question 37

what percent of pts had good outcomes with the Lapidus

Answer 37

91%

Question 38

indications for a Lapidus

Answer 38

- instability of the 1st ray - long 1st MT - IMA >25 - underlying neuromuscular disease - genetic conditions such as Down syndrome

Question 39

what is epiphysiodesis

Answer 39

arresting the lateral physic of the 1st MT base and allowing the medial physic to continue to grow

Question 40

advantage of epiphysiodesis

Answer 40

less surgery | less post-op disability (WB immediately)

Question 41

what is the golden period for epiphysiodesis

Answer 41

btw ages 9-14 F: 10-12 M: 11-14

Question 42

where should the staple be placed for epiphysiodesis

Answer 42

dorsal to plantar in the lateral 25% of the MT base across the physis

Question 43

what procedure is done in conjunction with epiphysiodesis

Answer 43

McBride bunionectomy

Question 44

what ancillary procedures are performed with juvenile HAV

Answer 44

- MA correction - cuneiform osteotomies - pes valgus reconstruction - ATL

Question 45

complications

Answer 45

- residual pain - jt stiffness - recurrence - hypertrophic scar formation

Question 46

T or F: adolescents are more likely to develop hypertrophic scars

Answer 46

T - they have a longer inflammatory phase in wound healing