1. D r Dhananjaya sabat MS, DNB, MNAMS
Assistant Professor Orthopedics
MAMC & STC, New delhi

2. INTRODUCTION
Lateral deviation of the great toe and medial
deviation of the first metatarsal
Progressive subluxation of the first
metatarsophalangeal (MTP) joint
Static deformity due to valgus angulation of
the distal articular surface of the first
metatarsal or the proximal phalangeal
articular surface.

3. Pathophysiology
 No single cause
 Intrinsic conditions: 1. Metatarsus primus varus: congenital
/ heriditary ( AD), 2. Pes planus, 3. ligamentous laxity, 4.
neromuscular
 Footwear: 15 times increased incidence
 female sex
 4th-6th decade age
 Rheumatoid arthritis

4. Anatomy
Four groups that encircle the first MTP
joint
1) Extensor hallucis longus and brevis
2) Flexor hallucis longus and brevis
3) Abductor
4) Adductor
Deforming Musculature
1. Abductor Hallucis
-Inserts in the plantar aspect of the proximal
phalanx
-Can draw the phalanx medial and push metatarsal
head lateral
2. Adductor Hallucis
-2 origins
-common tendon to plantar aspect of proximal
phalanx and lateral aspect of plantar
plate/sesamoid complex

5. Anatomy
Plantar Plate
 2 seasmoids
incorporated into
tendons of FHB
 Plantar Plate formed
by tendons of
Adductor
Hallucis, Abductor
Hallucis, FHL and
Joint Capsule

6. Fig 8


7. Clinical Presentation
PAIN over the medial eminence (Bunion).
 Pressure from footwear is the most frequent cause of this
discomfort.
 Bursal inflammation
 Irritation of the skin
 Breakdown of the skin may be noted.
 Bunion consists of:
 Bony exostosis / prominence of the metatarsal head
 Overlying subcutaneous bursa
 Hyperkeratosis of dermis

8. Pronated Toe Fig 6

9. Physical Examination
 Skin : calluses, areas of redness
 Sites of pain
 Magnitude of the hallux valgus deformity
 Pronation of the great toe
 Motion of 1st MTP joint- increased or decreased, Pain or crepitus,
or both, with motion of the MTP joint
 Metatarsocuneiform joint for hypermobility
 Examiner grasps the first metatarsal with the thumb and
index finger and pushes it in a plantar lateral-to-dorsomedial
direction; mobility > 9 mm represents hypermobility
 Pes planus deformity , Contracture of the Achilles tendon
 Mobility and structure of foot in general
 Gait analysis

10. Radiographic Examination
 Weightbearing AP & Lateral
 Axial (Sesamoid)
 Assess for bone and joint deformity
 Length and shape of 1st MT
 Congruent vs. Incongruent joint
 Osteoarthrosis
 Forefoot alignment is evaluated for metatarsus Adductus
 Hindfoot is Inspected for Pes Planus or Pes Cavus.

11. Measure Angles
 Hallux Valgus angle:
Intersection of longitudinal axis
of 1st MT and proximal
phalanx. Normal < 150
 Intermetatarsal angle
Intersection of 1st and 2nd MT.
Normal < 90 ; increased with
metatarsus primus varus

12.  Distal Metatarsal Articular Angle
(DMMA)
Defines the relationship of the distal articular
surface of the 1st MT to the longitudinal axis.
Quantities the magnitude of lateral slope of
articular surface.
With subluxation, the articular surface deviates
laterally in relationship to the 1st Metatarsal.
Usually < 60 .
 Proximal Phalangeal Articular Angle
(PPAA)

13. SEVERITY OF
DEFORMITY
CLASSIFICATION MILD MODERATE SEVERE
Hallux valgus angle < 20° 20° to 40° >40°
1-2 intermetatarsal angle 11° or less. 12- 15° 16° or more
Subluxation of the < 50% 50% to 75% > 75%
lateral sesamoid, as
measured on an AP
radiograph

14. TREATMENT
 Non-operative vs. Operative
 All patients should be treated non-operatively
first.
Despite conservative measures, some patients
eventually need surgical intervention.

15. Treatment
NON-OPERATIVE
Footwear Modification
 Widen toe box
 decrease lateral deviation of great toe
 decrease inflammation and pain
 Decrease heel height
 prevent forward slide of the foot
 Arch support
 may negate effects of pes planus

16. Contracture of the Achilles tendon
 Stretching exercises
 Lengthening of the Achilles tendon
Thermoplastic night splints

17. Treatment
SURGICAL
 Indications:
 Persistent PAIN not cosmetic complaints
 Progression of deformity
 Failure of non-operative treatment
 Goals:
 Correct all pathologic elements and yet maintain a
biomechanically functional forefoot
 Usually will not result in a foot with normal
appearance
 Combine soft tissue procedures with bony
procedures in almost all cases.

18. Treatment
SURGICAL: SOFT TISSUE PROCEDURE
Distal Soft-Tissue Reconstruction
Medial and lateral procedures
 Hallux Valgus angle <30 degrees
 IMA < 15 degrees
 High rate of recurrence if done without bony procedure
 Medial and lateral procedures at the same time contraindicated.
Medial Procedures Lateral Procedures
 Tighten lax capsule  Capsular release
 advancement, plication or resection  adductor longus release or transfer
 Abductor must not be detached  Division of transverse MT ligament
 risk NV bundle
•Medial side procedure recommended
•Be aware of cutaneous branch of medial plantar nerve.
• Lateral procedure more difficult.
•Neurovascular risk.

20. Treatment
SURGICAL: Bony Procedures
 Distal MT: for IM angle 12-150
 Mitchell {step cut}
 Wilson {Oblique}
 Chevron
 Proximal MT: for IM angle > 150.
Medial opening wedge, lateral
closing wedge, cresentic or dome
 Phalangeal: Proximal Phalanx Osteotomy-Akin
 Combination osteotomies
 Arthrodesis of MCP jt / Keller’s excission for arthritis of MTP jt.
 Metatarsocunieform procedures: arthrodesis (Lapidus) for hypermobile
first ray

21. Distal MT Osteotomy
Mitchell Chevron

22. Proximal Cresenteric
Osteotomy

23.  Double Osteotomy
Technique

25. Surgical Algorhythm
HVA IMA Procedure
< 40° < 13° to 15° modified McBride or
distal chevron osteotomy
< 40 ° > 13° to 15° modified McBride and
proximal osteotomy
>40° > 20° modified McBride and
proximal osteotomy or arthrodesis

26. Complications
SURGERY
 Recurrent deformity 20-30%
 Hallux Varus
 Pronation deformity
 Pain
 Neurologic Injury
 Osteonecrosis
 Physeal injury/arrest
 Nonunion/malunion