Forefoot Anatomy & Disorders

Question 1

What are the stabilizers of the first MTP?

Answer 1

1. Collateral ligaments
2. Intrinsic muscles
3. Extrinsic muscles

Question 2

Which intrinsic muscles stabilize the 1st MTP?

Answer 2

1. EHB - extensor hallucis brevis
2. FHB - flexor hallucis brevis
3. Abductor hallucis
4. Adductor hallucis

Question 3

Which muscles insert onto the 1st metatarsal head?

Answer 3

None

Question 4

The ____ ligament connects the 1st metatarsal sesamoids to the 2nd metatarsal.

Answer 4

Deep transverse ligament

Question 5

What structure keeps the 1st metatarsal sesamoids aligned under it?

Answer 5

Crista - bone ridge under the 1st metatarsal head

Question 6

Identify the angles used to evaluate severity of hallux valgus on AP weight bearing xrays of the foot?

Answer 6

1. Hallux valgus angle (HVA)
2. Intermetatarsal angle (IMA)
3. Dista metatarsal articular angle (DMAA)

Question 7

What are the normal ranges of HVA, IMA, and DMAA when evaluating hallux valgus on Xray?

Answer 7

1. HVA < 15 deg
2. IMA < 9 deg
3. DMAA < 10 deg

Question 8

Which HVA and IMA angles are associated with mild hallux valgus deformity?

Answer 8

HVA < 20 deg, IMA 12 deg

Question 9

Which HVA and IMA angles are associated with moderate hallux valgus deformity?

Answer 9

HVA 20-40 deg
IMA 12-15 deg

Question 10

Which HVA and IMA angles are associated with severe hallux valgus deformity?

Answer 10

HVA > 40 deg, IMA > 15 deg

Question 11

Postop incomplete reduction of ______ is a risk factor for recurrence of hallux valgus.

Answer 11

sesamoids

Question 12

What is the recommended treatment for hallux valgus deformity with HVA < 30 deg and IMA <13 deg?

Answer 12

Distal metatasal osteotomy (Chevron) +/- distal soft tissue release

Question 13

What is the recommended treatment for hallux valgus deformity with HVA > 25 deg and IMA > 13 deg?

Answer 13

Proximal metatarsal osteotomy +/- soft tissue release

Question 14

What is the recommended treatment for hallux valgus deformity with HVA > 40 deg and IMA > 16 deg?

Answer 14

Proximal metatarsal osteotomy or Lapidus procedure +/- distal soft tissue release

Question 15

What is the Lapidus procedure?

Answer 15

Metatarasal cuneiform fusion = fuses the joint between the first metatarsal and the medial cuneiform in the midfoot.

Question 16

What are the indications for the lapidus procedure?

Answer 16

1. Severe hallux valgus deformities (large IMA)
2. Hypermobility or instability at the first MTC joint.
3. TMTJ arthritis

Question 17

What are signs of 1st MTP hypermobility?

Answer 17

1. Increased motion (dorsiflexion) on clinical exam.
2. Gapping or oblique subluxation of 1st MTC on weightbearing xray
3. 2nd MTC arthritis
4. Metatarsalgia

Question 18

What is the Akin procedure?

Answer 18

Medial closing wedge osteotomy of the proximal phalanx

Question 19

What is the indication for the Akin procedure?

Answer 19

Hallux interphalangeus

Question 20

What is released in the modified Mcbride procedure?

Answer 20

Lateral structures:
1. Adductor hallucis tendon
2. Deep transverse ligament
3. Lateral capsule of the 1st MTPJ

Question 21

Which structure is the primary deforming force that produces valgus and pronation of the 1st MTP?

Answer 21

Adductor hallucis tendon

Question 22

What complication is associated with the chevron procedure?

Answer 22

AVN of the metatarsal head due to stripping of the superficial branch of the medial plantar artery.

Question 23

What is the most appropriate surgical treatment for transfer metatarsalgia with a relatively elongated second ray in a patient who previously underwent a lapidus procedure for left hallux valgus?

Answer 23

shortening osteotomy of the second metatarsal