This document summarizes a seminar on hallux valgus (bunions). It provides details on the relevant anatomy, biomechanics, causes, symptoms, physical exam findings, radiographic assessment, classification, and treatment options for hallux valgus. Conservative treatments include footwear modifications and stretching exercises. Surgical treatments aim to correct the structural deformities and include soft tissue procedures, distal and proximal metatarsal osteotomies, phalangeal osteotomies, fusions, and resection arthroplasty. The Mitchell and Chevron osteotomies are described as common distal metatarsal osteotomy techniques.

1. Department Of Orthopaedics
J.J.M. Medical College– Davangere
Seminar on….
HALLUX VALGUS
MODERATED BY : PRESENTED BY
Dr. Maheshwarappa .D Dr. Venkatesh Ghantasala
Professor & unit chief Post Graduate
Dr. shivashankarappa.A
Assistant Professor
on 02-12-2015

2. RELEVANT ANATOMY

3. BONES OF THE FOOT :

6. SESAMOID COMPLEX AND PLANTAR PLATE

7. LIGAMENTOUS ATTATCHMENTS AROUND HALLUX

8. MUSCLE ATTACHMENTS

9. FOOT BIOMECHANICS :
 The MTP articulation alone bears one-third of the weight of the forefoot and helps
stabilize the longitudinal arch through the attachment of the plantar aponeurosis into
its base.
 Immediately after the foot hits the ground during ambulation, weight is rapidly
transferred from the heel to the metatarsal head region
 As a step is taken, the toes are pushed into dorsiflexion
 The plantar aponeurosis, which arises from the medial tubercle of the calcaneus
and inserts into the base of the proximal phalanx, is pulled over the metatarsal head.
 This passively depresses the metatarsal heads and raises the arch. This construct is
commonly called the “windlass mechanism”.
 Any disorder of the first metatarsophalangeal joint has the potential to disrupt this
critical mechanical function. Weight is then transferred to the lesser metatarsals, and
secondary pathology in the remainder of the fore foot can develop.

10. Windlass Mechanism

12. THE HALLUX VALGUS
 Carl Hueterto defined the deformity
 Most commonly encountered deformities of the forefoot characterized by lateral
deviation of the great toe and, medial deviation of the first metatarsal with static
subluxation of the first metatarsophalangeal (MTP) joint
 Commonly known as a BUNION DEFORMITY after the noticeable prominence on
the medial side of the foot - “BUNIO” meaning Turnip
 vague term - as it has been used to denote any enlargement / deformity of the
MTP joint like bony medial eminence in case of Hallux Valgus, enlarged bursa
overlying the metatarsophalangeal joint, ganglion, gouty arthropathy etc .

13.  The toe not only deviates, but it also rotates into pronation. Nail turns to face
toward the instep.
 As these deformities develop, the lateral capsule and the Adductor Hallucis Tendon
on the lateral side of the first MTP joint become contracted. The medial capsule
becomes attenuated
 In the majority of cases, the first metatarsal itself deviates to the medial side, a
deformity known as Metatarsus Primus Varus.
 While this happens the intermetatarsal ligament between the second metatarsal
head and lateral sesamoid remains unchanged in length.
 The sesamoids therefore retain their original position with regard to the rest of
the foot and the first metatarsal head subluxates off of them

14. ETIOLOGY / RISK FACTORS :
 Extrinsic Factors
 Shoes with high heel.
 Shoes with narrow toe box.
 Occupational factors
 Intrinsic Factors
 Heredity - 60% to 90%
 Pes Planus
 Hypermobility of Metatarsocuneiform joint
 Medial slanted Metatarsocuneiform joint
 Hyperpronated 1st ray
 Ligamentous laxity
 Pronation of hind foot
 Achilles Contracture
 Metatarsus primus varus
 Neuromuscular disorders like CP, Stroke
 Systemic conditions like Rheumatoid Arthritis
 Female preponderance
 Age : 4th-6th decade
 Miscellaneous factors : 2nd toe amputation; Cystic degneration of medial capsule

15. PATHO ANATOMY
 Angle between the 1st and 2nd metatarsals is more than the 8 to 9
degrees usually considered to be the upper limits of normal.
 Valgus angle of the 1st MTP joint also is more than the 15 to 20 degrees
considered to be the upper limits of normal
If the valgus angle of the first metatarsophalangeal joint exceeds 30 to 35
degrees, pronation of the great toe usually results.
With this abnormal rotation, the abductor hallucis, which is normally plantar to
the flexion-extension axis of the first metatarsophalangeal joint, moves further
plantarward
In this case, the only restraining medial structure is the medial capsular
ligament with its capsulosesamoid portion and capsulophalangeal portions
The unopposed adductor hallucis pulls the great toe further into valgus,
stretching the medial capsular ligament particularly capsulosesamoid portion
Attenuated medial capsular ligament , allow the metatarsal head to drift
medially from the sesamoids

17. Finally, the sesamoid ridge on the plantar surface of the first metatarsal head (the
crista) flattens because of pressure (abutment) from the tibial sesamoid
With this restraint lost, the fibular sesamoid displaces partially or completely into
the first intermetatarsal space
In this situation, the patient is bearing less weight on the first ray and more on
the lesser metatarsal heads, increasing the likelihood of transfer metatarsalgia,
callosities, and stress fracture of a lesser metatarsal
Sometimes severe crossover toe deformity of second toe associated with severe
hallux valgus known as HAMMER TOE DEFORMITY. Here pain beneath second
metatarsal head is Primary complaint .

18. SIGNS AND SYMPTOMS
 Asymptomatic
 Pain- the primary symptom of hallux valgus is PAIN over the medial
eminence.
 Pressure from footwear is the most frequent cause of this discomfort.
 Valgus deformity
 Tenderness
 aesthetic or cosmetic concerns
 Full blown or full spectrum of hallux valgus presents as -
- Varus deformity of the first metatarsal,
- Valgus of the great toe,
- Bunion formation,
- Arthritis of the first metatarsophalangeal joint,
- Hammer toe of one or more toes,
- Corns,
- Calluses and
- Metatarsalgia

19. PHYSICAL EXAMINATION
Skin - callosities and corns
Sites of pain
Magnitude of the hallux valgus deformity
Pronation of the great toe
Motion of 1st MTP joint
Metatarsocuneiform joint for hypermobility
Pes planus deformity , Contracture of the Achilles tendon
Neurovascular status of the limb
Mobility and structure of foot in general
Gait analysis
Deformities of lesser toes

20. RADIOGRAPHIC ASSESSMENT :
 Standard series of radiographs which are critical in the evaluation of the
deformity and guiding the treatment should include –
 Weight-bearing radiographs of the Foot in AP, LATERAL and OBLIQUE views.
 Non-weight bearing AXIAL or SESAMOID view
 The Information that should be gleaned from the films includes :

21. •Assess for bone and joint deformity
•Length and shape of 1st MT
•The relative lengths of the first and second metatarsals
•The presence or absence of deformity in the hallux itself.
•The presence or absence of arthritis at the first MTP or in the midfoot
•The presence or absence of instability at the first metatarsocuneiform joint
•Forefoot alignment is evaluated for metatarsus Adductus
•The hallux valgus angle
•Joint congruency (Congruent vs. Incongruent joint
•The distal metatarsal articular angle formed by the alignment of the first
metatarsal and the margins of the joint surface of the first MTP
•The intermetatarsal angle formed by the axes of the first and second metatarsals
on the AP view

22. Hallux Valgus Angle
Normal <15
Mild <20
Moderate 20-40
Severe >40

23. 1st/2nd Inter Metatarsal Angle (IMA) :
Normal <9
Mild <11
Moderate 11-16
Severe >16

24. Distal Metatarsal Articular Angle (DMAA) :
 defines the relationship of the articular surface of the distal first metatarsal with
the longitudinal axis of the first metatarsal
Quantities the magnitude of lateral slope of articular surface. It is usually less than <
6 degrees

25. Hallux Interphalyngeal Angle
The angle made by the longitudinal axes of the proximal and distal phalynges of
the great toe

26. Subluxed Vs Congruent Joint :
A. Hallux valgus deformity with subluxation (non congruent joint) is characterized by
lateral deviation of the articular surface of the proximal phalanx in relation to the
articular surface of the distal first metatarsal.
B. Hallux valgus deformity with a nonsubluxated (congruent) metatarsophalangeal
joint is caused most often by lateral inclination of the distal metatarsal articular
surface
A. Subluxed joint B. Congruent joint

27. CLASSIFICATION NORMAL MILD MODERATE SEVERE
HALLUX VALGUS ANGLE < 15* < 20° 20° to 40° > 40°
1-2 INTERMETATARSAL
ANGLE
< 9* 11° or less. 12 - 15° 16° or more
SUBLUXATION OF THE
LATERAL
SESAMOID, AS MEASURED
ON AN AP RADIOGRAPH
Nil or
minimal
< 50% 50% to 75% > 75%
Classification

29. TREATMENT
1. Conservative Management
2. Surgical Management

30. Conservative Management :
1. FOOT WEAR MODIFICATION
 First line of treatment
 Widening of toe box
 Decreasing the heel height
 Enhanced arch support may negate effects of pes planus.
2. TA STRETCHING EXERCISES AND TA LENGTHENING.
3. THERMOPLASTIC NIGHT SPLINTS
4. BUNION AIDS AND STRAPPING –
Bunion pads (like a Polo/doughnut shape) can help to offload the tender bunion,
But strapping and overnight splints are probably a waste of money with no
quality research to support their use.
5. CHIROPODY - can help by taking care of the callosities and skin compromise.
6. PODIATRY – may help to correct the foot biomechanics

32. Surgical Management
 Indications :
Persistent symptoms for atleast 2 years.
Progression of deformity.
Failure of non-operative treatment like foot wear modification.
 Should not be performed for cosmetic reasons alone.
 Goals :
 To correct all pathologic elements and yet maintain a biomechanically
functional fore foot .
 To obtain a pliable plantigrade and cosmetically acceptable foot

33. Any procedure chosen must take into account the following structural
components……………………….
Valgus deviation of the great toe (hallux valgus).
Varus deviation of the first metatarsal.
Pronation of the hallux, first metatarsal, or both.
Hallux valgus interphalangeus.
Arthritis and limitation of motion of the first metatarsophalangeal joint.
Length of the first metatarsal relative to lesser metatarsals.
Excessive mobility or obliquity of the first metatarsomedial cuneiform joint.
The medial eminence (bunion) .
The location of the sesamoid apparatus.
Intrinsic and extrinsic muscle-tendon balance and synchrony.

34.  More than 130 operations have been recommended for the treatment of
Hallux Valgus.
 Various surgical procedures in general……………….
1. Soft Tissue Procedures
Indicated in very mild disease in young female (almost never alone)
2. Distal MT Osteotomies
Indicated in mild disease
3. Proximal MT Osteotomies
4. Combined MT Osteotomies
Indicated in more moderate disease
5. Phalangeal Osteotomies
6. Fusion Procedures / Joint Arthrodesis
Indicated in severe disease with progressing degenerative changes.
7. MTP Resection Arthroplasty
Only indicated in elderly patients with low functional demand

35. SOFT TISSUE PROCEDURES :
MODIFIED MCBRIDE PROCEDURE :
 Release of adductor hallucis, transverse metatarsal ligament, and lateral
capsule combined with excision of medial eminence and placation of the
capsule medially.
This procedure was modified to retain the lateral sesamoid, which helps
to prevent hallux varus (which as common with original mcbride
bunionectomy);
 As this procedure attempts to re-align the mtp joint, it is best performed
on an incongruent joint
INDICATIONS :
•30 to 50 year old woman with clinical symptoms and a history of
conservative management failure.
•HVA --- 15 to 25 degrees
•IMA --- less than 13 degrees.
•HVI --- less than 15 degrees
•No degenerative changes at the metatarsophalangeal joint

36. Modified Mcbride Bunionectomy :
Three staged procedure –
 MEDIAL CAPSULAR INCISION , JOINT REDUCTION AND MEDIAL EMINENCE REMOVAL.
 RELEASE OF VALGUS DEFORMING FORCES i.e. Adductor hallucis, flexor hallucis
brevis , deep transverse intermetatarsal ligament and lateral capsule.
 FIBULAR SESMOIDECTOMY (if needed) AND MEDIAL CAPSULAR IMBRICARTION .

37. MEDIAL CAPSULAR INCISION , JOINT REDUCTION AND MEDIAL EMINENCE
REMOVAL.

39. RELEASE OF VALGUS DEFORMING FORCES

40. FIBULAR SESMOIDECTOMY (if needed) AND MEDIAL CAPSULAR IMBRICARTION

41. METATARSAL OSTEOTOMIES :
1. Mitchell {step cut
osteotomy}
2. Wilson
3. Chevron
4. Modified chevron
1. Proximal Crescentic
2. Proximal Chevron
3. Opening Wedge
4. Ludloff
5. Mau
6. Closing Wedge
7. Scarf
DISTAL MT OSTEOTOMIES PROXIMAL MT OSTEOTOMIES

42. DISTAL METATARSAL OSTEOTOMIES
Done for HVA ≤ 40, IMA < 13
Mitchell’s osteotomy :
1.SKIN AND CAPSULAR INCISION
 dorso-medial incision
 distally based flap is then created from the medial joint capsule in order to
expose the medial eminence.
2. MEDIAL EMINENCE REMOVAL
3. EXPOSURE OF THE METATARSAL NECK AND DISTAL SHAFT AND PLACEMENT
OF GUIDE HOLES
 Drill two holes perpendicularly through the metatarsal shaft from the dorsal
to the plantar direction.
 Pass an absorbable suture through the holes so that it can be tied dorsally.

43. 4. DOUBLE OSTEOTOMY OF THE METATARSAL NECK
 Make the first cut distally perpendicular to the medial border of the metatarsal
neck which is incomplete and should leave 3 to 6 mm of lateral shaft intact.
 second osteotomy in a similarly perpendicular direction to the metatarsal shaft,
starting medially 3 to 4 mm proximal to the first cut which is complete
5.LATERAL DISPLACEMENT OF THE CAPITAL FRAGMENT
 manually shift the entire capital fragment laterally until the lateral spike rests on
the lateral cortex of the proximal fragment.
 Tie the suture while the capital fragment is plantar flexed about 10 degrees
plantar flexion
6. CAPSULAR CLOSURE (MEDIAL CAPSULORRHAPHY)

45. Chevron Osteotomy
Accepted widely for the correction of mild and moderate hallux valgus deformities
Reduces risk of dorsal displacement
straight midline medial incision
capsular incision longitudinal in the midline (medial) of the medial eminence
The medial eminence is excised
V shaped osteotomy is planned in transverse plane in the metatarsal head near the
subchondral bone such that each of the dorsal limb and plantar limb of V should
make 30 degrees of angle with longitudinal axis of MT shaft.
Shift the capital fragment laterally by thumb pressure.
Medial capsulorrhaphy is done after bringing the hallux into 5 degrees of valgus.
Medial projection of the metatarsal on the proximal side of the osteotomy is
Shaped into the contour of the metatarsal neck and distal shaft.

46. Chevron osteotomy. A, Skin and capsular incision (do not denude metatarsal head of soft tissue). B, Medial eminence
removal. C, Osteotomy should be in cancellous bone—not in cortical bone of metatarsal neck. D, Proper angle of
osteotomy in horizontal plane. E, Correct coronal plane of osteotomy. F, Correct technique of pushing metatarsal head
fragment laterally. G, Avoid excessive lateral displacement of capital fragment. H, Removal of overlapping proximal
fragment.

47. Modified Chevron Osteotomy:
 The modified chevron osteotomy is simply a more proximal placement of the
apex of the osteotomy in the metatarsal head.
Potential problems of this modification of the chevron osteotomy are
instability of the osteotomy and insufficient metaphyseal bony contact. Proper
placement of the osteotomy cuts is mandatory.
The metatarsal osteotomy must be internally fixed. .
 Used for more severe deformities up to 35 degrees of hallux valgus and up to
15 degrees of first to second intermetatarsal diversion.

48. Proximal Metatarsal Osteotomies :
 If varus of the first metatarsal, whether primary or secondary, contributes to
the hallux valgus complex, correction near the origin of the deformity is reasonable
 In addition, a few degrees' shift of the metatarsal at its base causes marked
improvement at the distal end of the metatarsal
 A patient without significant degenerative arthritis in the first
metatarsophalangeal joint and with hallux valgus of more than 35 degrees and
an intermetatarsal angle of more than 10 degrees may benefit from a proximal
metatarsal osteotomy and a distal soft-tissue procedure at the metatarsophalangeal
joint.

49. An osteotomy at the base of the metatarsal has the following advantages
Cancellous bone and broad contact surfaces of the fragments promote early
stability (3 to 5 weeks) and union (6 to 8 weeks)
Small changes in position at the osteotomy produce excellent correction at the
distal end of the metatarsal where the symptoms are located
Narrowing of the forefoot improves the variety of footwear possible and gives
an excellent cosmetic result
Large angles between the first and second metatarsals can be corrected.
Slightly tilting the distal fragment plantarward reduces load bearing by the
second metatarsal, decreasing the chance of transfer metatarsalgia.
The metatarsal is shortened minimally, if at all, unless the surgeon chooses a
technique that intentionally shortens it (the width of the osteotomy cut itself is
more than compensated for by the “straightening of the bone”).

50. Currently, the most frequently used proximal metatarsal osteotomies are
-

52. Proximal Crescentic Osteotomy
1st stage - The first incision is made dorsally in the intermetatarsal space to
release the adductor hallucis, the deep transverse intermetatarsal
ligament, and the lateral capsule of the first metatarsophalangeal joint.
2nd stage - The second incision is made midline-medial over the medial
eminence to remove the medial eminence and perform a capsulorrhaphy
3rd stage -
 Dorsal longitudinal incision
Score the dorsal aspect of the metatarsal transversely at 1 and 2 cm levels
distal to the metatarsocuneiform articulation.
first scored mark represents the osteotomy site, and the second represents
the area for placement of the screw
Drill a 3.5 mm hole 1 cm distal to the osteotomy site in the center of
the metatarsal shaft, and direct it proximally 45 degrees to the metatarsal

53. Using an oscillating saw with a crescent shaped saw blade placed convex
distally, begin the osteotomy on the most proximal scored mark
Displace the proximal fragment medially, rotate the distal fragment around the
osteotomy site and fix the osteotomy site with a screw.
Complications :
 Limitation of motion of the first metatarsophalangeal joint
 Dorsiflexion malunion of the osteotomy site with transfer metatarsalgia
 Hallux varus.

56. Proximal Chevron Osteotomy:
 The primary benefit of this configuration of the osteotomy is the increased stability
at the osteotomy site, although it must be internally fixed with a pin or screw
 medial eminence removal
 release fibular sesamoid-metatarsal ligament and the conjoined tendon of the
adductor hallucis muscle from the lateral aspect of the sesamoid.
 Do not divide the transverse metatarsal ligament
 percutaneously pass a large Dacron braided polyester suture around the second
metatarsal neck. The needle emerges beneath the first metatarsal into the wound.
 Grasp the free end of the suture with the hemostat, and pull it beneath the skin
and tendons to emerge over the first metatarsal through the wound medially
 Using a suture passer, pass the deep leg of the suture through a 2-mm transverse
hole drilled in the dorsal half of the first metatarsal head-neck junction.
 Make a transverse chevron osteotomy with an angle of 45 degrees and with the
apex directed distally at the diaphyseal-metaphyseal junction of the first metatarsal.

57.  After rotating the distal fragment of the osteotomy laterally to correct the
metatarsus primus varus, hold the osteotomy in the corrected position with a guide
pin,
 Insert a 4-mm screw from the plantar aspect of the distal fragment, and direct it
laterally and dorsally across the osteotomy into the proximal fragment. The screw should
not cross the tarsometatarsal joint
Before final tightening of the screw, tie the large Dacron “lashing” suture
 At this point, the alignment of the sesamoids is partially corrected
 The capsular closure holds the sesamoids beneath the first metatarsal head and
corrects the hallux valgus

59. Scarf Osteotomy
 Horizontally directed displacement Z-osteotomy made at the diaphyseal level.
 This configuration has a high level of intrinsic stability, particularly in the
sagittal plane, and provides a broad surface area of bony healing
Stability of the osteotomy allows early weight bearing and return to activities.
 Scarf osteotomy has become popular because of its versatility it allows
 Elongation or shortening of the first metatarsal
 Medial displacement of the capital fragment to correct hallux varus
 Plantar displacement to increase the load of the first ray
 Lateral displacement of the plantar bone fragment to reduce the intermetatarsal
angle
 Current indications for the scarf osteotomy are mild-to-moderate deformities
(intermetatarsal angle of 11 to 18 degrees and hallux valgus angle 20 to 40 degrees)

61. Ludloff Osteotomy :
 Ludloff described an oblique osteotomy of the first metatarsal oriented from
dorsoproximal to distal plantar.
 He originally shortened the metatarsal without using internal fixation; this
technique was abandoned for many years because of its inherent instability.
 With the development of newer fixation methods that added stability, the
technique has gained popularity.
 Biomechanical studies have shown that the Ludloff osteotomy fixed with lag
screw compression is more rigid than proximal crescentic and other proximal first
metatarsal osteotomies.
Advantages
 Slight supination of the cut (8 degrees) that allows plantar flexion of the first
metatarsal, theoretically minimizing the risk of transfer metatarsalgia further
 Simplicity (involving only a single cut in the bone).
 Angular correction through bony rotation that allows the surgeon to “dial in” the
precise amount of correction desired
 Mechanical stability that allows early ambulation

63. Mau Osteotomy
Proximal oblique orientation is opposite to that of the Ludloff osteotomy, with
proximal plantar and distal dorsal exit points
Fixation is with two cannulated screws placed from dorsal to plantar,
perpendicular to the osteotomy
Sagittal saw is placed parallel to the weight-bearing surface of the foot and the
osteotomy is completed from proximal-plantar to distal-dorsal
Because of the plane of the osteotomy, it has greater initial stability with weight-
bearing when compared to the Ludloff

64. Medial Cuneiform Osteotomy :
 Center a medial longitudinal incision over the first cuneiform
 Fix the osteotomy with crossed K-wires or a cancellous screw, and close the wound
in the routine manner
 The medial eminence of the metatarsal head can be used as an interposition graft
 Distract the osteotomy site with a lamina spreader, and impact the bone graft
 Direct the osteotomy in a mediolateral plane, and carry it to a depth of 1.5 cm,
ensuring that the dorsal and the plantar cortices are transected.

65. PROXIMAL PHALANGEAL OSTEOTOMY OR AKIN OSTEOTOMY :
 Used primarily for Hallux Valgus Interphalangeus deformity
After medial eminence removal and adductor tenotomy from the base of proximal
phalynx a medial closing –wedge phalangeal osteotomy is done and ostetomy closed
and stabilized with the help of 2 K wires passed from distal to proximal through the
phalanges and ostetomy site
Mostly used in combination with 1st MT osteotomies for greater correction in
congruent joint.
 Contraindications for the procedure are the following:
• Rheumatoid arthritis
• Moderate-to-severe osteoarthritis at the metatarsophalangeal joint
• Intermetatarsal angle more than 13 degrees
• Hallux valgus angle more than 30 degrees
• Subluxation laterally of the tibial sesamoid more than 50% of its width.
• Open physis of the proximal phalanx

67. ARTHRODESIS OF THE FIRST METATARSOPHALANGEAL JOINT
Indications :
 Severe deformity (an intermetatarsal angle > 20 to 22 degrees, a hallux
valgus angl e > 45 degrees, and severe pronation of the hallux)
Degenerative arthritis with hallux valgus.
 Possibly for mild-to-moderate deformity when motion of the MTP joint is
limited and painful
Recurrent hallux valgus
 Hallux valgus in patients with rheumatoid arthritis
Posttraumatic hallux valgus with severe disruption of all medial capsular
structures that cannot be adequately reconstructed.
Hallux valgus caused by muscle imbalance in patients with neuromuscular
disorders, such as cerebral palsy, to prevent recurrence

68. Follolowing techniques of arthrodesis are described :
 Arthrodesis with Small plate fixation / Low-profile contoured dorsal plate and
compression screw fixation
 Truncated Cone Arthrodesis
 Wire Loop Arthrodesis
 Ball-and-Socket Arthrodesis (Molded Arthrodesis)
 Arthrodesis of 1st Metatarsocunieform Joint ( Lapidus Procedure )

69. Arthrodesis with Small plate fixation / Low-profile contoured dorsal
plate and Compression Screw Fixation

70. Truncated Cone Arthrodesis

71. Ball And Socket Arthrodesis (Molded Arthrodesis) :
 Make a midline medial incision
 Remove all cartilage and subchondral bone
 Prepare the base of the proximal phalanx by deepening the natural concave
surface
 Align the joint surfaces in the proper position of dorsiflexion, valgus, and neutral
rotation.
 Impact the surfaces, and hold them with two K-wires
Evaluate the final position of the metatarsophalangeal joint (15 degrees of valgus,
25 degrees of extension to the longitudinal axis of the first metatarsal and neutral
rotation
 Drill a hole through the metatarsal head into the proximal phalanx.
 Overream the metatarsal side of the arthrodesis with
 Insert a full-threaded, 4-mm cancellous screw from the metatarsal head into the
proximal phalanx

72. Arthrodesis of the First Metatarsocuneiform Articulation
(Lapidus Procedure)

73. Mann described an excellent algorithm for selecting the appropriate
operative procedure in the treatment of hallux valgus and hallux rigidus.