hallux valgus Flashcards
Define hallux valgus?
- Lateral deviation of the great toe with medial deviation of the 1st metatarsal
- 2 forms exist
- Adult hallux valgux
- Adolscent & juvenile hallux valgus
What is the aetiology of hallux valgus ?
- Multi factorial
- INTRINSIC- genetic , lig laxity, pes planus, RA, CP
- EXTRINISIC- type of shoe- narrow box and high heel
What is the epidemiology of hallux valgus?
- More common in women
-
70% pts have FHx
- genetic predisposition with anatomic anomalies
-
Risk Factors
- Genetic predisposition
- increased distal metaphyseal articular angle (DMAA)
- Ligamentous laxity of 1st Tarso-metatarsal joint instability
- Convex metatarsal head
- 2nd toe deformity/amputation
- pes planus
- Rheumatoid arthritis
- Cerebral Palsy
- Extrinsic- shoe with high heel and narrow toe box
Describe the pathology of hallux valgus?
- The medial capsule attenuates due to repetitive loading
- Ist MT head has no muscultendinous attachments and moves progressively medially, off sesmoids
- Semsoids remain within FHB tendon & are attached to base of proximal phalanx
- Lateral deviation of proximal phalanx-> abductor hallicis migrates plantar and lateral
- Ehl and fhl move lateral
- Extensor hood stretches –> muscle imbalance to PLANTARFLEX and PRONATE GREAT TOE (ABD H)
- Secondary contracture of lateral capsule
- windlass mechaniams become ineffective
- leads to transfer metatarsalgia
Name any associated conditions?
- Hammer toe
- Callosities
What are the factors that differentiate juvenile/adolescent hallux valgus ftom adults?
- Bilateral
- familial
- Pain not usually primary complaint
- Varus of 1st MT with widening of IMA usually present
- DMAA usually increased
- Often associated with a flexible flatfoot
complications
- Recurrence is common >50%
- Overcorrection
- Hallux varus
What are the signs and symptoms of HV?
Symptoms
- Difficulty with shoe wear due to medial eminence
- Pain over prominence at MTPJ
- Compression of digital nerve-> symptoms
Signs
- Hallux rests in valgus and pronated due to deforming forces ( Adbuctor hallucis plantar and lateral)
- Examine 1st mt for
- IST MT ROM
- 1st TMT mobility
- Callous formation
- sesmoid pain/arthritis
- pes planus
- lesser toe deformities
- midfoot & hindfoot conditions
Can you decribe/ draw the anatomy of the 1st mt and the effect of hallux valgus on this?
Normally
- EHB dorsal
- Abductor Hallucis medial with FHB medial - medial plantar
- Adductor hallucis and FHB lateral -lateral plantar
HV
- EHB moves Medial
- Adbuctor hallucis ( moves plantar and lateral ) to becomes plantar to MT
- FHB medial, FHB lateral and Adductor hallucis move lateral
What investigations are useful for HV?
- Standard WB views AP, Lateral and oblique of foot
- findings
- Lateral displacement of sesmoids
- joint congreuency and degenerative changes can be evaluated
- radiological parameters
What is the hallux valgus angle? What is normal?
- The angle formed by a line along the first metatarsal shaft and a line along the shaft of proximal phalanx
- Normal < 15 degrees
Describe the first/second intermetarsal angle? What is the normal value?
- The angle formed by a line along the shaft of the first metatarsal shaft and line along second metatarsal shaft
- Normal < 9 degrees
Describe the hallux valgus inter phalangeus angle? What is normal?
- The angle formed by line along shaft of proximal phalanx and a line along the shaft of distal phalanx
- Normal < 10 degrees
How do you determine congruency of a joint?
- By comparing the line connecting the medial and lateral edge of the first metatarsal head articular surface with the similar line for the proximal phalanx When parallel the joint is congruent
Described the dmaa angle - what is normal ?
- The distal metatarsal articular angle
- The angle formed by a line along the articular surface of the first metatarsal and a line perpendicular to axis of the first metatarsal
- Normal <15 degrees
What would tx of HV be ?
Non operative
- Show modification, Pads. Orthosis
- first line tx
- orthoses more helpful in pt with pes planus/metatarsalgia
operative
- not for cosmesis alone
-
Soft tissue proceedure
- mild disease
-
Distal osteotomy
- mild disease (IMA <13)
-
Proximal or combined osteotomy
- More moderate disease IMA >13
-
1st TMT arthrodesis
- arthritis at TMTJ or instability
-
Fusion procedure
- severe deformity/spacticity/arthritis
-
MTP resection arhroplasty
- elderly pt, low functional demands
Describe a Modified Mcbride release for HV?
- Included release of ADDUCTOR HALLUCIS from lateral sesmoid/prox phlanx
- Lateral capsulotomy
- Medial capsular imbrication
- aim to correct an incongruent MTPJ
- never appropriate in isolation
combine with
- medial eminence resection
- MT osteotomy
- 1st TMT athrodesis ( lapidus)
What would the tx be for a patient with an IMA <13, HVA <40?
- DIstal metatarsal osteotomy = CHEVRON +/- Distal soft tissue release Medial eminence resection and capsular repair
What would the tx be for a patient with an IMA >13 degrees and a HVA >40?
- Proximal metatarsal osteotomy = SCARF
- + Modified Mc Bride
- + MT eminence resection
What would the tx be for a patient with Instability at 1st TMTJ/ joint laxity?
What are the other indications for this proceedure?
- A Lapidus proceedure- 1ST Metatarsocuneiform arthrodesis with modified McBride release
- Arthritis at TMTJ
- Metatarsus primus varus
- Severe deformity V large IMA
What would the tx be for a patient with an increased DMMA >10 degrees?
Distal metatarsal rediretional osteotomy and metatarsal transitional ostoetomy
What would the tx be for a patient with an HVA > 10 degrees?
- Akin osteotomy
What are the indications for 1st MTPJ arthrodesis
- Cerebral Palsy
- Down’s syndrome
- RA
- Gout
- Severe DJD
- Ehler- Danlos
What would the tx be for an elderly patient with low demands and diffuse angles
- KELLER’s EXCISION ARTHROPLASTY
- largerly abandoned
What are the complications of HV surgery?
- AVN- medial capsulotomy insult to MT head blood flow
- RECURRENCE- under correction of IMA, isolated soft tissue proceedure ( modified Mcbride), isolated medial eminence excision
-
DORSAL MALUNION- with transfer METATARSALGIA
- overload of lesser MT heads
- risk with shortening MT
- Lapidus
-
HALLUX VARUS
- over correction of 1st IMA
- xs lateral release w overtightening of medial eminence
- overresection of medial 1st MT head
- lateral sesmoidectomy
-
COCK UP TOE DEFORMITY
- injury to FHL
- complx of Kellers
-
2nd MT transfer METATARSALGIA
- ** seen with weils **
-
NEUROPRAXIA
- neuroma from medial branch of dorsal cutaneous nerve - terminal branch of superificial peroneal n. injured ot medial approach for capsular imbrication/MT osteotomy
What are the key tx options with Juvenile HV?
Non operative
- shoe modification - persue until physis closed
Surgical
- best to wait until PHYSIS closed
- skeletal mature
- Can’t preform MT Osteotomies/ Lapidus if PHYSIS is OPEN- Cuneiform osteotomy is ok
- soft tissue proceedure alone not successful
- if symptomatic wuth IMA>10o and HVA >20o
What is the tx for a juvenile with a DMMA of >20?
- Double MT osteotomy- AKIN for HVI, Biplanar chevron, open wedge cuneiform osteotomy
What isi the main complication to juvenile HV post surgery?
- Reoccurance
Can you draw a chevron osteotomy?
Can you draw a scarf osteotomy?
