Please confirm topic selection

Are you sure you want to trigger topic in your Anconeus AI algorithm?

Please confirm action

You are done for today with this topic.

Would you like to start learning session with this topic items scheduled for future?

Updated: Jun 27 2023

Bunionette Deformity

Images
https://upload.orthobullets.com/topic/7017/images/Xray - Richardson_moved.png
https://upload.orthobullets.com/topic/7017/images/30_moved.jpg
https://upload.orthobullets.com/topic/7017/images/Clincical photo - Richardson_moved.png
https://upload.orthobullets.com/topic/7017/images/type_1_rad.jpg
  • summary
    • Bunionette Deformities, commonly called tailor's bunion, are prominences on the lateral aspect of the 5th metatarsal head that most commonly occur as a result of compression of the forefoot.
    • Diagnosis is made clinically with presence of a prominence on the lateral aspect of the 5th metatarsal head, often associated with pain and callus formation.
    • 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
      • commonly seen in adolescents and adults
      • 2-4x more common in women
      • often bilateral deformities
  • Etiology
    • Pathophysiology
      • mechanism of disease
        • extrinsic causes
          • compression of forefoot (e.g. tight shoes)
          • abnormal loading on the lateral aspect of the foot
        • intrinsic causes
          • congenital deformities (e.g. splayfoot, brachymetatarsia)
          • inflammatory arthropathies
          • residual malalignments from surgery
      • pathoanatomy
        • boney prominence +/- bursitis over lateral aspect of 5th metatarsal head
        • increased 4-5 intermetatarsal angle (normal 6.5-8 degrees)
        • increased lateral deviation angle (normal 0-7 degrees)
        • increased width of MT head (normal <13mm)
        • lateral bowing of the 5th metatarsal bone
    • Associated conditions
      • varus MTP joint
      • pes planus
  • Classification
      • Bunionette Deformity Classification
      • Type I
      • Enlarged 5th MT head or lateral exostosis
      • Type II
      • Congenital bow of 5th MT, normal 4-5 IMA
      • Type III
      • Increased 4-5 IMA (most common)
  • Presentation
    • History
      • effect on activities and employment
    • Symptoms
      • cosmetic deformity
        • medial deviation of 5th toe
        • prominence of the 5th metatarsal head
      • pain
        • lateral bunion
        • plantar callus
        • worse with constrictive shoe wear
    • Physical exam
      • inspection
        • plantar or lateral hyperkeratosis
        • widened forefoot
        • erythema and swollen 5th bunion
        • check shoe wear
      • motion
        • often painless passive ROM of 5th MTP joint
  • Imaging
    • Radiographs
      • recommended views
        • standard weight-bearing films, dorsoplantar, lateral & oblique films
      • characteristic findings
        • increased 4-5 IMA (normal 6.5-8 degrees)
        • increased lateral deviation angle (normal 0-7 degrees)
        • increased width of MT head (normal <13mm)
    • CT scan
      • indications
        • ancillary studies rarely required
        • may be used if there is associated trauma or malignancy
  • Treatment
    • Nonoperative
      • NSAIDS, shoe wear modification, orthotics, keratosis padding, callous shaving
        • indications
          • indicated as first-line treatment of all types
          • asymptomatic deformities
        • techniques
          • semi-rigid shoe inserts
          • wide based shoes
          • stretching the forefoot of existing shoes
        • outcomes
          • 75-90% success rate
    • Operative
      • lateral condylectomy
        • indications
          • symptomatic Type I deformities
        • technique
          • resection of lateral third of the 5th MT head
          • combine with tightening of lateral MTP joint capsule
        • outcome
          • does not require extended period of immobilization
      • distal metatarsal osteotomy
        • indications
          • Type 2 and 3 deformities if IMA is < 12 degrees
        • technique
          • different techniques described
            • chevron-medializing osteotomy (most common)
            • distal transverse osteotomy
            • peg-and-slot type osteotomy
            • stepcut osteotomy
          • better stability of fragments with internal fixation (e.g. K-wire or screw)
          • may be combined with distal condylectomy and tightening of lateral capsule
        • outcomes
          • chevron osteotomy is biomechanically the strongest construct compared to the other proximal osteotomies
      • oblique diaphyseal rotational osteotomy
        • indications
          • symptomatic Type 2 and 3 if IMA is > 12 degrees
        • technique
          • shave plantar aspect 5th MT head if plantar callosity present
          • proximal osteotomy should be avoided due to poor blood supply in this region of the metatarsal
          • fixation achieved with screw
        • outcomes
          • may produce 5th MT shortening
      • metatarsal head resection
        • indications
          • salvage procedure only
          • leads to unacceptable instability of MTP joint
  • Complications
    • Recurrence
      • is the most common complication with condylectomy alone
    • Transfer metatarsalgia
      • seen with isolated metatarsal head resection
    • Claw toe
Card
1 of 12
Question
1 of 12
Private Note