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- 3-Dimensional deformity with Lateral deviation of great toe, medial deviation of 1st MT and pronation deformity
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- Perara Current concepts review JBJS 2011
- 1. Failure of medial supporting structures joint capsule is “early and essential step”
- 2. Bone – MT head drift medially, PP moves laterally (valgus)
- 3. Muscles Deformity – , EHL and FHL act as bowstring and act as adductors together with AdH; Sesamoids articulate with lateral MT head
- 4. MT head drop off sesamoid, causing pronation and plantar flexion
- 5. Contracture – Lateral joint capsule and intrinsics contracts
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- Defunctioning of first ray ➔ Transfer metatarslagia ➔ Stress on 2nd MT ➔ Plantar plate rupture ➔ dorsiflexion of Proximal phalanx ➔ Hammer toe
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- Non- Modifiable Female, family history, ligamentous laxity, Pes planus, tight TA, Underlying conditions (RA, cerebral palsy)
- Modifiable High heel, narrow toe box
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- Intrinsic causes = idiopathic, familial, hyperlaxity, Inflammatory (RA, Gout), Neuromuscular
- Extrinsic (acquired) = due to tight foot wear
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- Extrinsic pain = pain due to deformity and pressure
- Intrinsic pain = pain due to degeneration, synovitis
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- "Weight bearing AP and Lateral XR"
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- HVA [15 ° ], IMA [10 °], DMAA [10 °], IPA [10 °]
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- Most are incongruent (DMAA < 10 °)I
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- Most are non congruent (DMAA < 10); so after correction, it becomes congruent and well aligned.
- If congruent, (DMAA > 10); osteotomy itself will cause it to be unaligned. So will need double osteotomy
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Figure A shows a congruent hallux valgus with DMAA < 10°. If we perform a proximal osteotomy, the joint will become subluxed. However, Figure B shows a non-congruent hallux valgus with DMAA > 10°. Ironically, when we perform a proximal osteotomy, this previously subluxed joint will now become congruent.
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- Will need double osteotomy.
- Medial closing wedge to correct DMAA first
- Followed by a proximal scarf osteotomy
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- "meaning that proximal phalanx can be rolled medially on metatarsal head to achieve correction of deformity"
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- Classifx by Severity by HVA and IMA angles (based on JBJS review by Robinson et al. 2007)
- Mild HVA < 20 °. IMA < 13
- Moderate 21 °- 40 °, IMA 14-20
- Severe > 40 °, IMA > 20
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- Wide shoe box, toe spacer
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- Do I need to fuse? - TMTJ OA or MTPJ OA?
- How big the correction do I need?
- Do I need to correct IPA? ➔ Akin's osteotomy
- Do I need to release gastroc?
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- Distal osteotomy = Chevron
- Proximal osteotomy = Scarf
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- “Combination of soft tissue and bony procedures”
- Supine, tourniquet.
- Lateral release (Modified Mcbride) first to mobilize sesamoid via dorsal incision (can be done as a second incision over 1st web space or through the medial incision)
- Bony Correction as required Scarf Osteotomy – “aim to place MT over sesamoid and achieve balance”
- KIV Akin’s osteotomy
- Medial tissue debridement + capsular stabilization – reef the attenuated medial capsule
- KIV Gastroc release if silverskoid positive.
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- Dorsal incision in the 1st web space at level of 1st MTPJ (separate from osteotomy incision) OR go through osteotomy trans-metatarsal
- Release varies from surgeon to surgeon but include
- Metatarso-sesamoid suspensory ligament (from MTPJ to sesamoids)
- Phalangeal insertion band (from PP base to fibular sesamoid)
- Adductor hallucis tendon
- Deep transverse metatarsal ligament
Lateral release via medial.pdf170.0KB
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- Medial longitudinal incision along midline of medial border of foot
- Protect medial dorsal cutaneous nerve (branch of SPN)
- Capsule divided and reflected dorsally - not plantarly to protect plantar artery
- Z-cut osteotomy - to prevent troughing, Coetzee 2003 reccomend that vertical limbs be only through cortical bone and not in cancellous bone
- Fix with variable pitch screws
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- V-shaped, extra-capsular, Distal 60 ° angle cut
- Lateral shift up t
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- Medial closing wedge osteotomy of proximal phalanx to address high Interphalangeus Angle
- Cut must be perpendicular to phalanx to prevent PF or DF
- Avoid "cock -up" deformity by protecting the FHL tendon
- Fix with screw or staple
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- Troughing is impaction of 2 osteotomy fragments, whereby the hard cortical bone impacts into soft cancellous bone, resulting in loss of MT height and malrotation.
- To prevent troughing, Coetzee 2003 reccomend that vertical limbs be only through cortical bone and not in cancellous bone
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- Lapidus Fusion indication = TMTJ OA, Hypermobile 1st ray, Primus Varus (large deformity)
- Modified Lapidus = isolated fusion of 1TMTJ (original included fusion of 1+2MT)
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- Keller’s resection arthroplasty ➔ low demand
- Simple bunionectomy alone not recommended --> 41% patients dissatisfied.
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- Divided into early vs Late
- Early complications
- Dorsomedial branch of SPN injury ➔ numbness over medial aspect of toe
- Infection
- Late
- Recurrence
- Painful neuroma from injury to Dorsal medial cutaneous nerve
- Hallux varus deformity - avoid resection of fibula sesamoid
- AVN rates 0-20%. Blood supply laterally from 1st Dorsal and plantar MT artery; medially from medial plantar artery. So, Prevention (2)
- 1. Avoid plantar dissection
- 2. Saw blade pass through but not beyond lateral cortex
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- If flexible ➔ Abductor hallucis release, medial capsule release
- Salvage - MTPJ arthrodesis
JUVENILE Hallux Valgus
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- High incidence of Family history - X-linked dominant/ Autosomal dominant with variable penetrance
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- Angles - large IMA with metarsus primus varus (etiology is the TMTJ)
- DMAA is typically increased (congruent HV)
- Presence of laxity - 1st ray laxity, Beighton +
- NO PAIN
- Often BILATERAL
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- Need TRO central causes of muscle imbalances e.g. Cerebral palsy, look at spine for spinal dysraphism
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- Pursue Non operative until physis closes
- Treat like for adult HV when physis closed ➔ due to hyperlaxity may need lapidus procedure