Here are the procedures I would suggest based on the findings in each case: Case 1: - Distal metatarsal osteotomy to decrease the intermetatarsal and hallux abductus angles and reduce the sesamoids. - Possible cheilectomy or excision arthroplasty to address the bone cyst and osteoarthritis. Case 2: - Distal metatarsal osteotomy or proximal phalangeal osteotomy to address the increased interphalangeal angle and metatarsus primus elevatus. - Possible cheilectomy to address the osteoarthritis. Case 3: - Distal metatarsal osteotomy to decrease the intermetatarsal and hallux abduct

1. BUNIONS: Reading the
X-ray

2. Review the Angles

3. Metatarsus Adductus
Angle
Normal – 15 degrees
• Rectus Foot: <15 degrees
• Birth: ~30 degrees
• At 1 year: ~ 20 degrees
• By age 4: 15 degrees

4. Intermetatarsal Angle
Aka
1. Metatarsus primus adductus
2. Metatarsus primus varus
• True IM angle = IM angle + (metatarsus
adductus angle – 15)

5. Hallux Abductus
Angle
• Normal – 0-15 degrees

6. PASA - Proximal
Articular Set Angle
Aka
1. DMAA: Distal metatarsal
articular angle

7. DASA - Distal
Articular Set
Angle
Normal – 7.5 degrees

8. HAIA – Hallux
Abductus
Interphalangeus
Angle
Normal – 10 degrees

9. Metatarsal
protrusion
Angle
Normal (+ or -) 2mm

10. Tibial Sesamoid
Position
Normal 1-3

11. Summary
1. PASA: 0-8
2. DASA: 0-8
3. HAIA: 0 – 10
4. HAA: 0 – 15
5. MAA: 0 – 15
6. IMA – 8 – 12

12. AJM Sheet: HAV Work-
up

13. In the area of the patient’s presenting complaint I see a (mild, moderate, or
severe) hallux abductovalgus deformity at the level of the metatarsal-
phalangeal joint as defined by a:
1. Increase in IM angle, (say- mild/mod/sev)
2. Tibial sesamoid position of approximately (1-7)
3. Increased hallux abductus angle, and
4. The PASA and DASA of this joint appear (within normal limits or
deviated).
5. There (does or does not) appear to be a hallux interphalangeus deformity
as defined by the (increased or normal) hallux interphalangeus angle.

14. The overall length of the first metatarsal appears
1. (normal, shortened, or long) compared to the remainder of the lesser
metatarsal parabola on the AP view.
2. There (is or is not) an underlying metatarsus adductus as defined by the
metatarsus adductus and Engle’s angles.
On the lateral view
• The 1st metatarsal appears (dorsiflexed, plantarflexed, or normal)
compared to the second metatarsal using Seiberg’s index.
• Generally, the rearfoot appears (rectus, pronated, or supinated) as defined
by...”

15. You can also address: Soft tissue density and volume
• Increase or decrease soft tissue density around 1st MPJ
• OR no soft tissue density observed
The 1st MPJ appears to be
1. Congruous, deviated, (or) subluxed
2. (Increase or decrease) joint space narrowing- uniform or non-uniform
3. Osteophytic lipping or spurting (Dorsal flag sign)
4. Degenerative joint space
5. Subchondral bone cysts
6. Adequate/inadequate bone stock
7. Hypertrophy of the medial eminence

16. Now that you have defined the location and severity of the deformity with
your angles, suggest procedures based on these specific abnormal findings.
For every abnormality that you described, suggest a procedure (or group of
procedures) to correct it.
1. “I would consider doing a distal metatarsal osteotomy in this case to
laterally translate and plantarflex the capital fragment of the first
metatarsal to decrease the intermetatarsal and hallux abductus angles in
addition to reducing the sesamoids.”
2. If you described the DASA and interphalangeus angles as normal, then
don’t suggest an Akin procedure!
3. If you described a mild deformity, then don’t suggest procedures that are
indicated for moderate to severe deformities!
4. I also use the above questions to classify each and every surgical
procedure. For each surgical procedure I think: This procedure will correct
for a (mild, moderate, or severe) deformity of this bone or at that joint.

17. Case 1
• Patient presents with CC of pain in
the first MPJ.
• Read the X-ray.

18. Case 1
• This is a Dorsoplantar view of left foot. The hallux abductus (22
degrees) and intermetatarsal (15 degrees) angles are increased.
The hallux interphalangeal angle is normal (5 degrees). The
proximal articular set angle (PASA, 7 degrees) is high normal. The
tibial sesamoid position is 6, and the first metatarsal head medial
eminence is prominent. The proximal and distal articular set axes
cross within the joint.
• Other findings: A geographic decreased density presents in the
medial aspect first metatarsal head and is bounded by a sclerotic
margin. The fourth and fifth toes are in adductovarus position,
and there are contractures at the lesser toe interphalangeal
joints. The primary trabeculations are prominent in the lesser
metatarsal heads.
• Diagnoses: Hallux abductovalgus with bunion deformity.
Subluxation, first metatarsophalangeal joint. Bone cyst. Toe
deformities. Osteoporosis.

19. Case 2 – Read the X-ray

20. Case 2
This is a DP view of the right foot. The
intermetatarsal and hallux abductus angles are
normal (7 and 6 degrees, respectively). The
interphalangeus angle is slightly increased (16
degrees). Other findings include osteophytes at
the joint margins (arrows) and a loose osseous
body superolaterally (arrowheads). The first
metatarsal axis is greatly dorsiflexed relative to
the talar axis.
Diagnosis: Osteoarthritis; hallux abductus
interphalangeus; metatarsus primus elevatus.

21. Case 2
Lateral View
This is a lateral view of the right foot. The intermetatarsal and hallux
abductus angles are normal (7 and 6 degrees, respectively). The
interphalangeus angle is slightly increased (16 degrees).
Other findings include osteophytes at the joint margins (arrows) and a
loose osseous body superolaterally (arrowheads). The first metatarsal axis
is greatly dorsiflexed relative to the talar axis.
Diagnosis: Osteoarthritis; Hallux abductus interphalangeus; Metatarsus
primus elevatus

22. Case 3 DP View
• Patient presents with CC of pain in
the first MPJ.
• Read the X-ray.

23. Case 3
This is a dorsoplantar view of the right foot. The met
adductus angle looks within normal limits. The hallux
abductus (25 degrees) and intermetatarsal (17 degrees)
angles are increased. The hallux interphalangeal angle is
normal (0 degrees). The proximal articular set angle (PASA, 6
degrees) is high normal. The tibial sesamoid position is 7, and
the first metatarsal head medial eminence is prominent. The
proximal and distal articular set axes cross within the joint.
Other findings: The second toe angulates medially relative to
the second metatarsal and is superimposed upon the hallux
distally. The fourth toe is in adductovarus position.
Diagnoses: Hallux abductovalgus with bunion deformity and
overlapping second toe. Subluxation, first
metatarsophalangeal joint. Toe deformities.

24. Time to Treat….
• You have read the X-rays and pointed out the abnormalities in the
radiographs…Now what?
• Can you list the procedures to treat the deformity?
• Check out the AJM Sheet: HAV Work-up Powerpoint.