Symptomatic hallux valgus associated with a first intermetatarsal angle greater than 15 degrees is typically corrected with a proximal first metatarsal osteotomy and distal soft tissue procedure when nonoperative treatment fails.
Multiple techniques for the hallux valgus deformity correction have been decribed.5
In 1918, Ludloff4 described an oblique osteotomy from the dorsal-proximal to distal-plantar aspects of the first metatarsal, and the procedure was performed without internal fixation.
The procedure recently gained renewed attention when Chiodo et al1 and Myerson6 recommended adding internal fixation and modified several parts of the technique.
The modified Ludloff osteotomy has been extensively studied with biomechanical and mathematical investigations.
ANATOMY
The special situation distinguishing the first metatarsophalangeal (MTP) joint from the lesser MTP joints is the sesamoid mechanism.
On the plantar surface of the metatarsal head are two longitudinal cartilage-covered grooves separated by a rounded ridge. The sesamoids run in these grooves.
The sesamoid bone is contained in each tendon of the flexor hallucis brevis; they are distally attached by the fibrous plantar plate to the base of the proximal phalanx.
The head of the first metatarsal is rounded and cartilage-covered and articulates with the smaller concave elliptical base of the proximal phalanx.
Fan-shaped ligamentous bands originate from the medial and lateral condyles of the metatarsal head and run to the base of the proximal phalanx and the margins of the sesamoids and the plantar plate.
Tendons and muscles that move the great toe are arranged in four groups:
Long and short extensor tendons
Long and short flexor tendons
Abductor hallucis
Adductor hallucis
Blood supply to the metatarsal head
First dorsal metatarsal artery
Branches from the first plantar metatarsal artery
PATHOGENESIS
Extrinsic causes
Hallux valgus occurs almost exclusively in shoe-wearing populations but only occasionally in the unshod individual.
Although shoes are an essential factor in the cause of hallux valgus, not all individuals wearing fashionable shoes develop this deformity.
Intrinsic causes
Hardy and Clapham2 found, in a series of 91 patients, a positive family history in 63%.
Coughlin5 reported that a bunion was identified in 94% of 31 mothers whose children inherited a hallux valgus deformity.
The association of pes planus with the development of a hallux valgus deformity has been controversial.
Hohmann was the most definitive proponent that hallux valgus is always combined with pes planus.
• Mann and Coughlin5 and Kilmartin3 noted no incidence of pes planus in the juvenile patient.
• Pronation of the foot imposes a longitudinal rotation of the first ray that places the axis of the MTP joint in an oblique plane relative to the floor. In this position, the foot appears to be less able to withstand the deformity pressures exerted on it by either shoes or weight bearing.8
The simultaneous occurrence of hallux valgus and metatarsus primus varus has been frequently described. The question of cause and effect continues to be debated.
PATIENT HISTORY AND PHYSICAL FINDINGS
Physical findings associated with hallux valgus deformity include the following:
Pain in narrow shoes
Symptomatic intractable keratoses beneath the second metatarsal head (in 40% of patients)
Lateral deviation of the great toe
Pronation of the great toe
Keratosis medial plantar underneath the interphalangeal joint
Bursitis over the medial aspect of the medial condyle of the first metatarsal head
Hypermobility of the first metatarsocuneiform joint
Physical examination for hallux valgus deformity should include the following:
Hallux valgus angle measurement: Normal is 15 degrees or less.
Intermetatarsal angle measurement: Normal is 9 degrees or less.
Sesamoid position measurements
Joint congruency
IMAGING AND OTHER DIAGNOSTIC STUDIES
Radiographs of the foot should always be obtained with the patient in the weight-bearing position, with anteroposterior (AP), lateral, and oblique views. The following criteria are examined:
Hallux valgus angle
Intermetatarsal angle
Sesamoid position
Joint congruency
Distal metatarsal articular angle: the relationship between the articular surface of the first metatarsal head and a line bisecting the first metatarsal shaft (normal is 10 degrees or less)
Arthrosis of the first MTP joint
DIFFERENTIAL DIAGNOSIS
Ganglion
Hallux rigidus
NONOPERATIVE MANAGEMENT
Comfortable wider shoes
Orthotics
Spiral dynamics physiotherapy in adolescents
SURGICAL MANAGEMENT
Indications
Symptomatic hallux valgus deformity with a first intermetatarsal angle of more than 15 degrees
Stable first metatarsal–cuneiform joint
Contraindications
Narrow metatarsal so that adequate rotation of the dorsal fragment is not possible
Severe osteoporosis
Skeletally immature patient
Severe osteoarthritic changes
Preoperative Planning
Standard weight-bearing AP and lateral radiographs are mandatory.
The hallux valgus and intermetatarsal angles and tibial sesamoid position are measured.
A preoperative drawing is helpful.
Clinical examination includes measurement of active and passive range of motion of the first MTP joint as well as inspection of the foot for plantar callus formation indicative of transfer metatarsalgia and stability of the first tarsometatarsal joint.
Positioning
The foot is prepared in the standard manner.
The patient is positioned supine.
An ankle tourniquet is optional.
Approach
The lateral soft tissue release is performed through a dorsal approach.
The Ludloff osteotomy is performed through a straight midline incision.