منو منو

Hallux Valgus

SUMMARY

    • Hallux Valgus, commonly referred to as a bunion, is a complex valgus deformity of the first ray that can cause medial big toe pain and difficulty with shoe wear.

    • Diagnosis is made clinically with presence of a hallux that rests in a valgus and pronated position. Radiographs of the foot are obtained to identify the severity of the disease and for surgical planning.

    • Treatment can be nonoperative with shoe modifications for mild and minimally symptomatic cases. Surgical management is indicated for progressive deformity and difficulty with shoe wear.  

  • EPIDEMIOLOGY

    • Demographics

      • more common in women

    • Risk factors

      • intrinsic

        • genetic predisposition

          • 70% of pts with hallux valgus have family history

        • increased distal metaphyseal articular angle (DMAA)

        • ligamentous laxity (1st tarso-metatarsal joint instability)

        • convex metatarsal head

        • 2nd toe deformity/amputation

        • pes planus

        • rheumatoid arthritis

        • cerebral palsy

      • extrinsic

        • shoes with high heel and narrow toe box

ETIOLOGY

  • Two forms exist

    • adult hallux valgus

    • adolescent & juvenile hallux valgus

  • Pathoanatamy

    • valgus deviation of phalanx promotes varus position of metatarsal

    • the metatarsal head displaces medially, leaving the sesamoid complex laterally translated relative to the metatarsal head

    • sesamoids remain within the respective head of the flexor hallucis brevis tendon and are attached to the base of the proximal phalanx via the sesamoido-phalangeal ligament

    • this lateral displacement can lead to transfer metatarsalgia due to shift in weight bearing

    • medial MTP joint capsule becomes stretched and attenuated while the lateral capsule becomes contracted

    • adductor tendon becomes deforming force 

       

      • inserts on fibular sesamoid and lateral aspect of proximal phalanx

    • lateral deviation of EHL further contributes to deformity

    • plantar and lateral migration of the abductor hallucis causes muscle to plantar flex and pronate phalanx

    • windlass mechanism becomes less effective

      • leads to transfer metatarsalgia

  • Associated conditions

    • hammer toe deformity

    • callosities

    • pes planus

      • associated with deformity progression 

         

  • Juvenile and Adolescent Hallux valgus 

    • factors that differentiate juvenile / adolescent hallux valgus from adults

      • often bilateral and familial

      • pain usually not primary complaint

      • varus of first MT with widened IMA usually present

      • DMAA usually increased

      • often associated with flexible flatfoot

    • complications

      • recurrence is most common complication (>50%), also overcorrection and hallux varus

ANATOMY

  • Pathoanatomy cascade

PRESENTATION

  • Symptoms

    • presents with difficulty with shoe wear due to medial eminence

    • pain over prominence at MTP joint

    • compression of digital nerve may cause symptoms

  • Physical exam

    • Hallux rests in valgus and pronated due to deforming forces illustrated above 

       

    • examine entire first ray for

      • 1st MTP ROM

      • 1st tarsometatarsal mobility

      • callous formation

      • sesamoid pain/arthritis

    • evaluate associated deformities

      • pes planus

      • lesser toe deformities

      • midfoot and hindfoot conditions

IMAGING

Radiographs

  • views

    • standard series should include weight bearing AP, Lat, and oblique views

    • sesamoid view can be useful

  • findings

    • lateral displacement of sesamoids

    • joint congruency and degenerative changes can be evaluated

    • radiographic parameters (see below) guide treatment

  • Radiographic Measurements in Hallux Valgus

  • Hallux valgus (HVA)

  • Long axis of 1st MT and prox. phalanx

  • Identifies MTP deformity

  • Normal < 15°

  •  
  • Intermetatarsal angle (IMA)

  • Between long axis of 1st and 2nd MT

  •  
  • Normal < 9 °

  •  
  • Distal metatarsal articular (DMAA)

  • Between 1st MT axis and line through base of distal articular cap

  • Identifies MTP joint incongruity

  • Normal < 10°

  •  
  • Hallux valgus interphalangeus (HVI)

  • Between long. axis of distal phalanx and proximal phalanx

  •  
  • Normal < 10°

  TREATMENT - ADULT HALLUX VALGUS

  • Nonoperative

    • shoe modification/ pads/ spacers/orthoses

      • indications

        • first line treatment

      • orthoses more helpful in patients with pes planus or metatarsalgia

  • Operative

    • surgical correction

      • indications

        • when symptoms present despite shoe modification

        • do not perform for cosmetic reasons alone

      • technique

        • soft tissue procedure

          • indicated in very mild disease in young female (almost never)

        • distal osteotomy

          • indicated in mild disease (IMA < 13)

        • proximal or combined osteotomy

          • indicated in more moderate disease (IMA > 13)

        • 1st TMT arthrodesis

          • arthritis at TMT joint or instability

        • fusion procedures

          • indicated in severe deformity/spasticity/arthritis 

             

        • MTP resection arthroplasty

          • only indicated in elderly patients with low functional demands

TREATMENT - JUVENILE AND ADOLESCENT HALLUX VALGUS

TECHNIQUES

  • Soft Tissue Procedures

    • modified McBride

      • indications 

        • goal is to correct an incongruent MTP joint (phalanx not lined up with articular cartilage of MT head). Usually done in patients with

          • a HVA less than 25 degrees 

          • IMA deformity less than 15 degrees

          • usually in patient 30-50 years of age

        • rarely appropriate in isolation

          • usually performed in conjunction with

            • medial eminence resection

            • MT osteotomy

            • 1st TMT arthrodesis (Lapidus procedure)

      • technique

        • includes

          • release of adductor from lateral sesamoid/proximal phalanx

          • lateral capsulotomy

          • medial capsular imbrication

          • (original McBride included lateral sesamoidectomy)

  • Metatarsal Osteotomies

    • distal metatarsal osteotomy

      • indications

        • mild disease (HVA 15-25°, IMA < 13°) 

           

        • unable to correct pronation deformity  

           

      • distal metatarsal osteotomies include

        • Chevron 

           

        • biplanar Chevron (corrects DMAA) 

        • Mitchell

        • may be combined with proximal phalanx osteotomy (Akin-medial closing wedge osteotomy)

    • proximal metatarsal osteotomy 

       

      • indications

        • moderate disease (HVA >40°, IMA >13°)

      • proximal metatarsal osteotomies include

        • crescentic osteotomy

        • Broomstick osteotomy

        • Ludloff

        • Scarf 

    • double (proximal and distal) osteotomy

      • indications

        • severe disease (HVA 41-50°, IMA 16-20°)

    • first cuneiform osteotomy

      • indications

        • severe deformity in young patient with open physis

  • Proximal phalanx osteotomies

    • Akin osteotomy 

       

      • indications

        • hallux valgus interphalangeus

        • congruent joint with DMAA <10°

        • as a secondary procedure if a primary procedure (e.g., chevron or distal soft-tissue procedure) did not provide sufficient correction due to a large DMAA or HVI

        • some authors perform Akin together with/at the time of proximal osteotomy+distal soft tissue correction because this results in progressive increase in HVI

  • Fusion procedures

    • Lapidus procedure (1st metatarsocuneiform arthrodesis with modified McBride) 

       

      • indications

        • severe deformity (very large IMA)

        • arthritis at 1st TMT

        • metatarsus primus varus

        • hypermobile 1st TMT joint 

        • concomitant pes planus

    • MTP Arthrodesis

      • indications are hallux valgus in

        • cerebral palsy

        • Down's syndrome

        • Rheumatoid arthritis

        • Gout

        • Severe DJD

        • Ehler-Danlos 

  • Resection arthroplasty

    • proximal phalanx (Keller) resection arthroplasty

      • indications

        • largely abandoned

        • rarely indicated in some elderly patient with reduced function demands

    • Surgical Indications for Specific Conditions

    • Juvenile/Adolescent with open physis

    • First cuneiform osteotomy

    • Hypermobile 1st MT

    • Lapidus procedure

    • DJD

    • MTP arthrodesis

    • Skin breakdown

    • Simple bunionectomy with medial eminence removal

    • Gout

    • MTP arthrodesis

    • Recurrence with pain in 1st TMT joint

    • Lapidus procedure

    • Rheumatoid arthritis

    • MTP arthrodesis

    • Down's syndrome, CP, Ehler-Danlos

    • MTP arthrodesis

  • Surgical Indications for Various Techniques to treat Hallux Valgus

  •  
  • HVA

  • IMA

  • Modifier 

  • Procedure

  • Mild

  • < 25°

  • < 13°

  • Distal MT osteotomy215737 

  •  Chevron osteotomy

  • Biplanar if DMAA > 10° with mod McBride

  • Moderate

  • 26-40°

  • 13-15°

  • Proximal MT +/- distal MT osteotomy

  •  Chevron/mod McBride + Akin

  • Proximal MT osteotomy and mod McBride

  • Severe 

  • 41-50°

  • 16-20°

  • Double osteotomy, DMAA > 15°

  • Proximal MT osteotomy plus biplanar chevron, mod McBride

  • Lapidus procedure plus Akin

  •  
  • 41-50°

  • 16-20°

  • Elderly/very low demand patient

  • Keller resection arthroplasty

  •  
  • 41-50°

  • 16-20°

  • Juvenile/Adolescent with DMAA > 20

  • Double osteotomy of first ray

COMPLICATIONS

  • Recurrence 

     

    • most common cause of failure is insufficient preoperative assessment and failure to follow indications 

      • e.g., failure to recognize DMAA > 10°

      • inadequate correction of IMA

      • e.g., failure to do adequate distal soft tissue realignment

    • more common in juvenile/adolescent population

    • noncompliant patient that bears weight

    • rounded shape to the first metatarsal head

    • residual tibial sesamoid lateral displacement

    • increased preoperative IMA and HVA

    • failure to perform a lateral release of the adductor hallucis tendon 

    • associated with incomplete reduction of the sesamoids 

       

  • Avascular necrosis 

     

    • medial capsulotomy is primary insult to blood flow to metatarsal head

    • distal metatarsal oseotomy and lateral soft tissue release inconjunction do not increase risk for AVN (Chevron plus lateral release thought to increase risk in the past)

      • treat with MTP arthrodesis with or without structural graft  

         

  • Dorsal malunion with transfer metatarsalgia

    • due to overload of lesser metatarsal heads

    • risk associated with shortening of hallux MT

      • Lapidus

      • proximal crescentric osteotomies

  • Hallux Varus 

     

    • caused by 

       

      • overcorrection of 1st IMA

      • excessive lateral capsular release with overtightening of medial capsule

      • overresection of medial first metatarsal head 

         

      • lateral sesamoidectomy 

         

  • Cock up toe deformity
    • due to injury of FHL
    • most severe complication with Keller resection
    • due to injury of FHL

    • most severe complication with Keller resection

  • 2nd MT transfer metatarsalgia 

     

    • often seen concomitant with hallux valgus

    • can occur secondary to malpositioning of MTP fusion 

       

    • shortening metatarsal osteotomy (Weil) indicated with extensor tendon and capsular release 

       

  • Neuropraxia 

     

    • Painful incisional neuromas after bunion surgery frequently involve the medial dorsal cutaneous nerve (a terminal branch of the superficial peroneal nerve). 

       

      • It is most commonly injured during the medial approach for capsular imbrication or metatarsal osteotomy.

تقویم حضور پزشک

برای رزرو نوبت به سایت زیر مراجعه کنید. رزرو نوبت