Hallux valgus procedures

Median eminence resection

· simple bunionectomy

· if combined with adductor hallucis release, called Silver procedure

Technique

· longitudinal medial skin incision

· triangular-shaped medial capsulotomy based distally with proximal longitudinal extension (Y-shaped incision)

· capsular flap raised

· medial eminence excised

· start at sagittal groove

· important to preserve groove for medial sesamoid

· more bone should be taken dorsally than from the plantar edge

· medial capsule plicated proximally (V-Y advancement) to correct valgus deformity

· abductor hallucis removed from plantar position and restored to more medial position by suture to base of V-Y flap

· toe held in overcorrected varus position and a slightly plantarflexed direction

· splintage by bandaging for four to eight weeks

Modifications

· horseshoe-shaped flap based proximally (blood supply better)

Indications

· elderly patient

· prominent medial eminence

· minimal hallux valgus deformity

Advantages

· simple with minimal soft tissue stripping

Disadvantages

· does not fully realign metatarso-phalangeal joint

Results

· reports vary

· one report is 65% subjective good results

Chevron distal osteotomy

Technique

· medial or dorsomedial skin incision

· terminal branches of medial division of superficial peroneal nerve and saphenous nerve must be avoided

· medial eminence identified

· longitudinal or Y-shaped capsular incision (as above)

· medial eminence removed (as above)

· dorsal metatarsal neck exposed

· excessive stripping of lateral capsule avoided

· to preserve blood supply to minimise risk of avascular necrosis of metatarsal head fragment

· to preserve soft tissue to prevent instability of osteotomy

· V-osteotomy made in horizontal plane

· in cancellous bone of metatarsal head (not neck)

· point of V in imaginary centre of metatarsal head

· angle of 60^o (each limb is angled 30^o from horizontal)

· capital fragment displaced laterally

· 4-5 mm and no more than 1/3 of width of metatarsal

· amount depends on hallux valgus angle

· osteotomy usually stable without fixation

· if unstable, K-wire used through dorsal aspect of head fragment into shaft

· medial projection on metatarsal on proximal side of osteotomy removed

· medial capsulorraphy performed

· if Y capsular incision, closed as V-Y

· if longitudinal capsular incision, longitudinal ellipse excised and closed to pull plantar tissues medially (sesamoid and abductor hallucis)

· postop treatment variable

· bulky soft dressing for 3 days then short leg walking cast for 3-6 weeks

· some use toe spica non weight-bearing for 6 weeks

Indications

· young patient (adolescent to 50)

· hallux valgus < 30^o

· intermetatarsal angle < 15^o

· no significant metatarso-phalangeal joint degeneration

Advantages

· very stable osteotomy with rapid healing

Disadvantages

· only limited realigment can be achieved

Complications

· avascular necrosis of metatarsal head

Results

· 90% patient satisfaction

Mitchell's distal osteotomy

Technique

· approach, capsulotomy and medial eminence resection as above

· 2 vertical holes drilled in metatarsal neck

· 1st hole 1.5 cm from joint, on medial side

· 2nd hole 1 cm proximal to 1st hole, on lateral side

· absorbable suture passed through holes so that it can be tied dorsally

· double osteotomy of metatarsal neck made

· 1st (distal) cut perpendicular to metatarsal shaft 3-4 mm proximal to distal hole

· 3-6 mm of lateral shaft left intact (more spike = more correction)

· 2nd (proximal) cut 3-4 mm proximal to 1st cut, completely through

· intervening bone removed

· fragment of MT head displaced laterally

· result

· MT shortened 3-4 mm

· varus inclination of MT reduced

· articular surface of 1st MT aligned with 2nd MT

· adductor relaxed

· sutured tied

· alternatively, K-wire may be used to secure osteotomy

· medial projection of bone on proximal side of osteotomy resected

· medial capsulotomy performed

· postop as for chevron

Indications

· middle-aged patient (30-60)

· hallux valgus < 30^o

· intermetatarsal angle > 15^o

· no degenerative changes in metatarso-phalangeal joint

Advantages

· more correction can be achieved than chevron osteotomy

Disadvantages

· less healing potential as done in cortical shaft rather than cancellous neck

· osteotomy not intrinsically stable and needs fixation

· technically difficult

Results

· 80% satisfactory outcome

Wilson’s shaft osteotomy

Technique

· approach, capsulotomy and medial eminence resection as above

· osteotomy of distal metatarsal shaft

· 45^o oblique

· starts medially at neck

· extends laterally and proximally to shaft

· distal fragment displaced

· slid proximally and laterally

· somewhat plantarward

· half the width of the bone

· medial capsulotomy performed

· postop as for chevron

Advantages

· good correction

· technically easy

Disadvantages

· significant shortening of hallux

· poor cosmesis

· may cause lateral transfer metatarsalgia

Results

· 90% satisfactory outcome

Keller's phalangeal excision arthroplasty

Technique

· medial incision centred over metatarso-phalangeal joint

· longitudinal capsular incision

· medial eminence and proximal half of proximal phalanx exposed

· soft tissue connections at base of proximal phalanx removed

· proximal third to half of proximal phalanx removed

· medial eminence excised

· capsulorraphy with double-breasted repair

· bulky soft dressing with toe in slightly overcorrected position - varus and plantarflexed

· bandaging to retain control of position for at least 3 weeks

Modifications

· insertion of longitudinal K-wire for 3 weeks

· purse-string suture to pull lax capsule between bone ends

Indications

· over age 60

· poor ambulator

· severe hallux valgus

· salvage procedure

Contraindications

· young

· active

· significant metatarsalgia

· significant arthritis of MTP joint

Advantages

· technically simple and predictable

· joint movement maintained

· no foreign material in joint

Disadvantages

· toe shortened and defunctioned

Complications

· recurrence of deformity

· hallux varus

· hallux extensus

· intrinsic minus hallux (claw toe)

· short, floppy, unattractive hallux

· transfer metatarsalgia

· hammertoe of second digit

Results

· 90% satisfaction

· excellent pain relief

· high latitude of footwear

arthrodesis of mtp joint

Technique

· approach as for Keller's

· joint opened

· bone ends exposed and denuded

· ends cut flat

· aim to achieve

1. dorsiflexion

· pulp of toe should be dorsiflexed 10-15^o from plantar aspect of soft tissue of foot

· depends on requirements of patients

· usually corresponds to 20-25^o dorsiflexion between proximal phalanx and metatarsal

· bony angle depends on height of medial arch

· more important to judge from soft tissue alignment

2. valgus

· 15^o valgus from 1st metatarsal

· surfaces apposed and held with screw

· from plantar aspect of proximal phalanx into medullary canal of metatarsal

· postop

· non-weight bearing plaster for 4 weeks and then weight-bearing plaster for further 4 weeks

Modifications

· joint surface area increased with Marin’s reamers

· metatarsal head fashioned into point with saw

· point directed somewhat medially and dorsally

· point made into cone with female reamer

· proximal phalanx broached with drill toward dorsal aspect

· base enlarged into cone with male reamer

· some adjustment possible when bone ends apposed

Indications

· all ages

· severe hallux valgus

· active

· hallux valgus with significant arthritis of metatarso-phalangeal joint

· halllux valgus with metatarsalgia

· rheumatoid hallux valgus

· hallux valgus in neuromuscular conditions

· salvage procedure

Advantages

· long-lasting

· excellent pain relief

Disavantages

· height of heel limited to 4 cm

· period of immobilisation required

Complications

· malposition

· excessive varus with footwear problems

· pronation with callus formation

· excessive extension with weakening of great toe and cockup deformity with flexion deformity of IP jt

· nonunion

Results

· 80-90% patient satisfaction rate

Replacement arthroplasty

Technique

· Swanson double-stemmed Silastic prosthesis

· both sides of joint excised but more of proximal phalanx excised

· better preserves relationship of metatarsal head to sesamoids

· lateral soft-tissue release

· post-operative splintage against recurrent valgus for at least 3 weeks

Indications

· elderly patient

· degenerative changes in MTP joint

· mild to moderate hallux valgus

· minimal metatarsus primus varus

· minimal demands on foot

· rheumatoid arthritis

Advantages

· function of toe maintained

· toe shortening decreased compared with Keller's

Disadvantages

· risk of infection

· silicone synovitis

· reaction to abraded particles of silicon

· in the form of painful swelling, redness and stiffness

McBride procedure

· most accepted technique is Mann modification of DuVries modification

Technique

Release of lateral contracture

· dorsal longitudinal incision in first interspace

· lateral MTP joint exposed

· longitudinal incision in capsule superior to adductor hallucis

· adductor hallucis tendon insertion isolated and detached along

· lateral aspect of joint

· base of proximal phlalanx

· lateral border of fibular sesamoid

· transverse metatarsal ligament divided

· neurovascular structures just deep to this

· lateral capsule torn by pulling great toe into varus

· capsule may need to be multiply perforated first

· sutures placed between 1st and 2nd metatarsal heads incorporating adductor hallucis

Repair of medial side of metatarso-phalangeal joint

· medial longitudinal incision over metatarso-phalangeal joint

· two vertical capsulotomies made with excision of intervening 5-8 mm capsular wedge

· medial eminence exposed and excised

Proximal metatarsal osteotomy

· performed if metatarsus primus varus is fixed

· dorsal incision at base of metatarsal dorsal and lateral to EHL tendon

· crescentic osteotomy performed with special saw blade

· 5-7 mm distal to metatarso-cuneiform joint

· metatarsal shaft rolled to realign the 1st and 2nd metatarsals to 5-10^o intermetatarsal angle

Reconstruction

· metatarsal osteotomy is fixed with a Steinmann pin

· medial capsule is plicated

· sutures between the metatarsal heads are tied

· compression dressing applied

Postop

· no cast

· pin is removed at four weeks

Indications

· all ages

· moderate hallux valgus <40^o

· moderate metatarsus primus varus (intermetatarsal angle < 15^o)

· no significant MTP jt degenerative changes

Advantages

· preserves function of great toe joint

· permits large amount of correction

Disadvantages

· extensive soft tissue dissection

· three incisions required

· recuperation long

· technically difficult

Complications

· recurrence of deformity

· hallux varus (10%)

· claw toe

· stiff metatarso-phalangeal joint

Akin varus osteotomy of proximal phalanx

Technique

· approach and removal of medial eminence as previously described

· initial incision extended distally

· varus osteotomy of proximal phalanx

· 1st transverse osteotomy 6-8 mm distal to metatarso-phalangeal joint

· 2nd oblique osteotomy 4-6 mm distal to 1st directed proximally to intersect with 1st at lateral cortex

· wedge of bone removed

· osteotomy closed

· held with K-wire

· short-leg cast for 6 weeks

Indications

· all age groups

· hallux valgus interphalangeus

· salvage procedure

· occasionally for hallux valgus

· hallux valgus < 30^o

· intermetatarsal angle < 15^o

· no degenerative changes in MP joint

Advantages

· simple

· rapid healing

Disadvantages

· deformity tends to recur