Embryology of the Upper limb and congenital hand anomalies Flashcards Preview

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Flashcards in Embryology of the Upper limb and congenital hand anomalies Deck (39):
1

Describe upper extremity embryogenesis

  • Wk 4-8 - at end of embryogensis, structures are present (including cartilage, not bone) and will then differentiate/mature
  • at birth - carpal bones and epiphyseal plates not yet ossified/not visible on xray

 

3 axes of development

  • derived from MESODERM (lateral plate & somatic)
  • PROXIMODISTAL = AER and PZ
    • Apical Ectodermal Ridge controls the apoptosis interdigital and guides differentiation of cells in Progress Zone defines digits
  • ANTEROPOSTERIOR = ZPA
    • Zone of Polarizing Activity defines A-P axis by amount of SHH signalling defines thumb on radial side
  • DORSOVENTRAL = WNT
    • Wnt singnalling in dorsal ectoderm defines nail pulp from plate

OSSIFICATION

  • clavicle first to ossify
  • Radius, ulna, DP, MC, PP, MP
  • Carpal bones post natal - C, H, Tq, L, STT, Pisiform

2

How do you classify and list congenital upper extremity deformities

IFSSH

  • FAILURE OF FORMATION
    • transverse arrest
    • longitudinal arrest
      • Ulnar longitudinal deficiency
      • Radial longitudinal deficiency
      • Central ray deficiency (cleft hand
      • longitudinal Intercalary deficiency (phocomelia)
  • FAILURE OF DIFFERENTIATION
    • Syndactyly
      • Apert
      • Acrosyndactyly
    • symphalangism
    • clinodactyly
    • camptodactyly
    • arthrogriposis
    • flexed thumb
      • trigger
      • clasped
  • DUPLICATION
    • Polydactyly
      • preaxial (thumb)
      • postaxial (little)
      • axial (central)
    • Ulnar dimelia (mirror hand)
    • Triphalangism
  • UNDERGROWTH
    • symbrachydactyly
    • hypoplastic/adactyly
  • OVERGROWTH
    • macrodactyly
    • limb
  • CONGENITAL BAND SYNDROME
  • GENERALIZED SKELETAL ABNORMALITIES

3

What is the incidence of congenital hand anomalies

1/600

and 10% of these have functional sequelae

4

What is the etiology of congenital hand anomalies

  • Unknown (60%)
  • Genetics (30%)
    • unknown mutations
  • Environment (10%)
    • Warfarin => limb hypoplasia
    • Dilantin => nail dysplasia, DP hypoplasia
    • Alcohol => nail dysplasia, DP hypoplasia
    • Thalidomide => phocomelia
    • Varicella =>longitudinal deficiency

5

At what age is power grip, tip pinch and hand preference established?

  • power grip: 7mths
  • tip pinch: 9mths
  • hand preference 3-4yo

6

What are the goals of surgical planning for correction of congenital hand anomaly

  • precise pinch
    • palmar pinch most used
    • lateral pinch also important
    • tip pinch precise but used less often 
  • power grasp

7

Failure of formation: Transverse arrest

What is the etiology, clinical presentation, management

  • Etiology
    • sporadic mutation
    • RFs: smoking, cocaine, misoprostol, CVS
  • Clinical presentation
    • usually, LEFT, UNILATERAL
    • level of amputation proximal forearm most common, then midcarpal/metacarpal
    • named according to last present structure
    • contralateral and proximal structures hypoplastic
    • may have finger nubbis/nails
  • Management
    • prosthesis is mainstay
    • may remove nubbins or not (usefu lfor sensory feedback)
    • revision of stump for prosthesis fitting

8

Failure of formation: longitudinal deficiency, Radial

What is the etiology, clinical presentation, classification

  • Etiology:
    • injury to AER
  • Clinical presentation
    • RIGHT, MALE
    • 50% bilateral
    • 50% associated with congenital syndrome
    • On exam -
      • wrist: unstable, radially deviated, pronation
      • ulna - bowed, shortened
      • radial structures absent (including muscle, nerve, vessel and upper arm/BP too
  • Classification: Baynes & Klug
    • Type 1 - <2mm hypoplastic radius
      • short epiphysis
      • no wrist angulation
    • Type 2: >2mm hypoplastic radius
      • short epiphysis and proximal hypoplasia
      • wrist radially deviated, supported
      • ulna bowed
    • Type 3: partial absence of radius
      • wrist radially deviated, unsupported
      • ulna thick, bowed, shortened+ anlage (fusion of tendon/fibrous tissue 2' to absnt muscle)
    • Type 4: Absent radius
      • ​most commone type
      • wrist: unstable, radial, pronated
      • ulna short bowed, anlage
      • elbow may be unstable

9

What syndromes are associated with radial longitudinal deficency and what work-up is necessary if RLD is identified?

  • Holt-Oram
    • ASD/VSD
  • VACTERL
    • Verterbral, Anam, Choanal/Cardiac, TE fistula, Renal, Limb
  • TAR
    • thrombocytopenia + absent radius
  • Fanconi
    • pancytopenia, ASD, poly/clino/syndactyly
  • Nager
    • craniosynostosis

 

WORK-UP

  • blood panel (low plat, pancytopenia)
  • cardiac echo (HO, VACTERL, Fanconi)
  • renal U/S (VACTERL)
  • xrays

10

How what are treatment options for RLD?

Non-operative

  • start at birth
  • splinting, serial casting, PT/hand therapy
  • improve position of wrist, maintain full PROM

 

Operative

Indicated: no wrist stability, extensor excursion

Contraindicated: elbow stiff (want wrist radial to feed)

  • Wrist/Hand 
    • centralization: realign 3rd MC with distal ulna and fixate (steinmann/kwire)
    • radialization: realign 2nd MC with distal ulna
    • ulnocarpal arthrodesis
    • closing wedge ulna osteotomy
  • Soft tissue relese/rebalance
    • tendon trasner FCU to ECU
    • release anlage to achieve ROM (watch median nerve

 

11

Failure of formation: longitudinal deficiency, Ulnar

What is the etiology, clinical presentation, classification

  • Etiology
    • ZPA abnormal
  • Clinical presentation
    • elbow unstable, fixed in flexion. fused w radius
    • wrist stable
    • Many associated HAND abnormalities: thumb hypoplasia, syndactyly ulnar digit, absense radial digit
    • wrist deviated ulnar
    • 25% bilateral
    • 50% associated with MSK defect or 3 syndromes (CdL, PFFD, Schinzel)
  • Classification (Baynes)
    • Type 1 - ulna hypoplastic
      • distal + proximal epiphysis present
    • Type 2 - partial ulna absence
      • ​most common
      • presence distal 1/3 only 
    • Type 3 - total ulna absence
    • Type 4 - radiohumeral synostosis (fusion)

12

What 3 syndromes are most commonly associated with ULD and what MSK abnormalities are associated w ULD

 

  • Cornelia de Lange
    • excess facial hair, short, DD, seizure
  • PFFD
    • proximal femoral focal deficiency
  • Schinzel
    • renal abnormalitiy, DD
  • MSK abnormalities
    • scoliosis, spia bifida
    • fibula/femur deficiency
    • contralat phocomelia

13

What are treatment options for ULD

Non-operative

  • splinting, serial casting to maintian PROM

Operative

  • Correct ass. HAND abnormalities
    • thumb recon: pollicization, web deepen, MC rotational osteotomy
    • syndactyly release
  • wrist/forearm/elbow
    • release anlage
    • rerotational radius osteotomy/humerus

14

What are difference between ULD/RLD

  • Incidence: RLD 10x more common
  • Associated syndrome/abnormalities
    • RLD - cardiac/renal/hematopoetic
    • ULD - MSK, DD
  • Hand abnormalities
    • RLD - thumb
    • ULD - syndactyly ulnar digit, absent radial 2-3digits
  • Elbow/wrist
    • RLD - elbow stable, wrist unstable
    • ULD - wrist stable, elbow unstable
    •  

15

Failure of formation: longitudinal deficiency, Central

How do you distinguish between the 2 types of central deficiency

  • cleft hand
  • symbrachydactyly

  • Cleft hand = D5 intact
    • V-shaped cleft
    • variable deficiency of D3
    • hypoplasia of radial digits
    • syndactyly 1st web
    • AR/sporadic genetics
    • MALE
    • BILATERAL
    • may have 1-4 limbs affected
    • no finger nubbins
    • carpal bones normal
    • Associated with: EED (ectrodermal-ectrodactyly Dysplasia w clefting), eye, nail, teeth abnormalities
  • Symbrachydactyly (thumbs up!)
    • U-shaped cleft
    • involves D2,3,4, leaving only D1/D5
    • hypoplasia/absence of ulnar digits
    • finger nubbins present
    • sporadic - no inheritance
    • UNILATERAL
    • only hands affected, normal legs/feet
    • carpal bones hypoplastic
    • Associated with POLANDS syndrome
  • Common to both
    • transverse lying MC bones
    • triphalangeal thumb, Longitudinal Bracketed epiphyses (clinodactyly)
    • PIP flexion contracture (camptodactyly

16

What are goals of treatment, treatment options and timing for both types of central deficiencies?

  • CLEFT HAND
    • Goal: pinch, grasp
    • Timing: early syndactyly release. 1-2yo for correction of cleft
    • Excise transverse MC
    • Syndactylyl release
    • Close Cleft: Snow-Littler technique: volar skin flap from cleft for 1st web adduction contracture, DTML recon with A1 pulley radial/ulnar flaps, transposition D2 to D3 MC base
    • Thumb hypoplasia/absence recon
  • SYMBRACHYDACTYLY
    • Goal: grasp
    • Timing: 4-5yo to consider 2nd toe trasnfer to D5 position
    • Excise finger nubbins
    • nonvascularized PP bone transfer for length
    • digit trasnposition to better position
    • free 2nd toe trasnfer to ulnar side of hand for grasp

17

Failure of Formation; longitudinal intercalary deficiency; Phocomelia

What is the definition, etiology, clinical presentation, classification and treatment options

  • Def: absence of segment between shoulde and hand - hand is normal in develop/presence of structures
  • Etiology
    • Ass RF: thalidomide, smoking, anticoagulants, anticonvulsants
    • Associated with syndromes:
      • CLP, Holt Oram, TAR, Adontia-adactylyl 
  • Classification - Frantz (based on absent structure)
    • Complete - absence of arm+forearm
    • Proximal - absence of humerus
    • Distal - absence of radius/ulna
  • Clinical presentation
    • BILATERAL commonly
    • presence of digital bones distinguishes from trasnverse arrest
  • Treatment options
    • aimed at positioned hand better in space
    • osteotomies (rotational, lenthening)
    •  

18

How do you distinguish symbrachydactyly from transverse arrest?

  • Nail plate (absent in arrest, present in Symbrachy)
  • U-cleft in SB, non cleft in Arrest
  • All digits are arrested at same level in Arrest (including thumb) but SB has different length digits

19

What are causes of CTS in ediatric population?

  • persistent median artery
  • anomalous muscle FDS
  • MPS (hurler syndrome)

20

Failure of Differentiation: Arthrogryposis multiplex congenita

What is the definition, clinical presentation, classification, treatment options

  • Definition
    • joint contracture and paralysis of extremities
  • Clinical presentation
    • bilateral, symmetric, affecting both LE & UE
    • cylindrical/fusiform appearing limbs
    • absence of skin creases/joint dimples
    • muscle atrophy, fibrosis
    • Assocaited with brachycephaly, club foot, tarsal fusions, carpal fusions
  • Classification:  Weekes
    • Single localized: hand or UE:  internal rotation, elbow extended, wrist flexed, pronated, ulnarly deviated, thumb in palm
    • Full expression: all limbs - as above for UE + shoulder adduction/internal rotation; LE hips adducted, internal rotated, knees flexed, club foot
  • treatment options
    • Non-operative - splint, serial casting
    • Operative - tendon trasnfers, rotational osteotomies

21

Failure of Differentiation: finger flexion deformities

  • trigger finger
  • clasped thumb

What is the definition, clinical presentation, classification (clasped only) treatment options

TRIGGER FINGER

  • Def: IP flexion deformity - due to A1 pulley or flexor sheath deformity
  • Clinical presentation: at birth or later, IP flexion deformity, palpable Nota's node. Familial inheritance.
    • Cannot passively correct
    • Associated with trisomy 13
  • No classification
  • Treatment
    • 1/3 resolve if present at birth by age 1
    • 1/10 resolve if present after birth
    • If no resolution >3yo, release A1 pulley

 

CLASPED THUMB

  • Def: MCP flexion deformity. Extensor lag at MCp +/-IP
  • Clinical presentation
    • on spectrum of thumb hypoplasia
    • absence of EPB MOST COMMON
    • BILATERAL, familial association
    • Associated with windblown hand (ulnar flexion MCP deformity), Whistling face Freeman Sheldon (long philtrum, windblown hand, rocker bottom feet
  • Classification: Weckesser
    • type1 - extensor lag only
    • type 2 - flexion contracture + extensor lag
    • type 3 - thumb hypoplasia
  • treatment accoding to weckesser
    • Type 1 - abduction thumb splint 6mths, if no improvement=> EPB absent, do EIP transfer
    • Type 2 - FPL lengthen, MCP jt release or MCP arthrodesis
    • Type 3 - release adduction contracture, EIP for EPL, PL for APL

22

Failure of Formation: Syndactyly

What is the etiology, epidemiology, clinical presentation, classification

  • etiology:
    • Failure of AER, apoptosis, digital patterning
  • Epidemiology:
    • most common Congenital hand anomaly (1:2000)
    • M:F 2:1
    • R>L
    • 50% bilateral (familial often bilat)
    • 25% inherited,  AD with variable penetrance
  • Clinical presentation
    • Patterns of Fusion: D3-4 > D4-5 >D3-2, >D2-1
    • Associated with 3 syndromes: Polands, Aperts, Acrosyndactyly
    • Associated with symbrachydactylyl, cleft hand/foot, toe syndactyly
    • Synonychia - fused Nail plate => complex
    • DIfferential motion fo DP =>simple
  • Classification
    • incomplete or complete: complete from web to tip at DIPjt, incomplete longer web
    • simple or complex: simple sc only, complex fusion of bones
    • Complicated: additional bones, some synostosis  

23

Failure of Formation; Syndactyly

Discuss treatment timing, goals, staging, procedures

TIMING

  • Early (6mth) if
    • fusion of different length digit (border)
    • complex
    • acrosyndactyly
  • Later (12-18mths)
    • all others - not after 3yrs b/c cortex patterning instilled

GOALS

  • as many functional digits as possible with fewest surgeries as possible
  • early separation of border digits
  • separation of nail plate, NV bundles, correct skeletal deformities
  • wide deep webs

STAGING

  • if multiple digits fused, staging to prevent ischemia, tension on closure
  • Stage 1 - release D1-2, D3-4
  • Stage 2 - release D4-5, D2-3

PROCEDURES

  • DIGIT SEPARATION
    • Dorsal flap: midline of adjacent digits, length 2/3rd distance form MCP to PIP.
    • Synchronous dorsal and volar zigzag flap
    • FTSG to deficien areas
  • Web deepening
    • Incomplete web: 3 flap webplasty (dorsal flap with interdigitating Z flap), 4flap z plasty, double opposing Zplasty
    • 1st web: as above + FDMA, dorsal skin flap, regional flap
  • Nail plate separation
    • excision of central portion and 1' closure
    • Buck gramco laterally based triangular tip flaps

24

Failure of formation: Acrosyndactyly

What is the definition, clinical presentation, treatment

  • Def: fenestration (sinus) proximally in web and distal fusion
  • Clinical presentation
    • bilateral
    • Associated with constriction band syndrome
    • may have complex fusions
  • Treatment
    • as syndactyly except timing early at 6mths

25

Failure of formation: Apert hand

What is the definition, classification and treatment

Def: complex synctalyly pathognomonic for Aperts =>fusion of D2,3,4 into central mass and D1/5 may be invovled. Thumb, if separate, radially deviated

Classification: Upton

  • Accoding to 1st and 4th web and central mass
  • Type 1
    • 1st&4th web: incomplete simple syndactyly
    • Central mass - flat, good MCPs, IP symphalangism, no synonychia
  • Type 2
    • 1st&4th web: complete simple syndactyly
    • Central mass - concave, synonychia with distal fusion of DPs and proximal splaying of MC
  • Type 3
    • 1st&4th web: complete complex syndactyly
    • Central mass - thumb incorporated, tight cupping, synonychia, D2 ray skeletal abnormalities

TREATMENT according to Upton's Type

  • Type 1-2, stage
    • Stage 1 - thumb corrected position w ostetomy and release 2nd and 4th web to create 3 digits
    • Stage 2 - release remaining digits
  • Type 3 
    • separate synonychia first (multiple infx risk)
    • then stage as above

26

What are the functional joints in Aparts complex syndactyly?

MCPs and D5 DIP

27

Failure of Differentiation: Cmaptodactyly

What is the definition, etiology, clinical presentation, classification, differential diagnosis, treatment options

  • Def: congenital PIPj flexion contracture
  • Etiology
    • unknown - Macfarlane hypothesized lumbrical anomalous insertion on D5 PP to act as flexor not extensor of IP
  • Clinical presentation
    • 2/3 bilateral,
    • AD w variable penetrance
    • may be congenital or acquired
  • Classification
    • Reducible or not
    • congenital or acquired
    • Type 1 - congenital - present at birth, isoalted, usually just D5
    • Type 2 - acquired - presents in preadolescent
    • Type 3 - severe - associated w syndrome
  • DDX
    • marfans, juvenile palmar fibromatosis
    • arthrogryposis, symphalangism, trigger finger
    • Beals syndrome (congenital contractural arachnodactyly
  • Treatment
    • Non-op - most
      • splinting, serial casting. Usual <30' can be corrected non-op
    • Operative - if >90 flexed, failed conservative
      • FDS trasnfer to extersor apparatus
      • lumbrical release
      • arthrodesis

28

What are 4 features on xray of camptodactyly?

LATERAL XRAY

  • flat dorsal head of PP
  • exaggerated recess neck of PP
  • narrowed PIP joint space
  • volar base beak on MP

29

Failure of Differentiation: Symphalangism

What is the definition, clinical presentation, classification, treatment

  • Definition; congenital stiffness of IPjts, most commonly PIP
  • Clinical presentation
    • AD
    • ulnar digits most common D5>D4>D3>D2
    • due to poor formation of joint surfaces and resulting ankylosis - usually stiff/fused in extension
    • poorly formed MP
  • Classification - Flatt
    • type 1 - true symphalangism - stiff w normal Phalangeal length
    • type 2 - symbrachydactyly - most common - stiff w shortened length
    • type 3 - symphalangism w assocaited abnoralities (clinodactyly, hearing defect)
  • Treatment
    • non-op - not effective
    • Operative; fusion in correct position

30

Failure of differentiation: clinodactyly

What is the definition, etiology, prsentation, classification, treatment?

  • Def: Angular deformity due to abnormal phalageal growth (longitudinal bracket epiphysis)
  • Etiology
    • epiphysis abnomrally present along diaphysis (C- J- shaped) leading to abnormal growth (delta phalanx)
  • Presentation
    • AD, inherited forms usually bilateral
    • D5 MP and D1 PP most common location
    • most comomn radial deviation D5 MP
    • Rarely in isolation
    • Assocaited with symphalangism, polydactyly, syndactyly, Polands, CLEFT foot
    • Associated with syndromes Apert/Pfeiffer (=>thumb delta phalanx), Downs (D5 delta phalanx)
  • Classification  - Cooney
    • type 1 - simple - bone <45'angulation
    • type 2 - simple complicated - bone >45'
    • type 3 - complex - bone and ST deformity <45' & syndactyly
    • type 4- coplex complicated - bone & ST deformity >45' & polydactyly /gigantism
  • Treatment
    • non-op not effetcive
    • OPeratie - only if >45' and functional/cosmetic defomrity
    • Osteotomies - closing/opening wedge, rotation, reversed

31

Failure of differentiation: triphalngeal thumb

What is the defintion, features, associations treatment

  • Def: hypersegmentation anomaly - 3rd phalanx
  • Features
    • abnormal phalanx
    • web contracture
    • thenar hypoplasia
  • Associated with 
    • Holt Oram, polydactyly, blood dyscrasias, cleft foot
  • Treatment
    • at 12mths
      • resect phalanx, deepend 1st web, opponenplasty if required later

32

How do you classify polydactyly

Stelling

Type I -  extra soft tissue mass only

Type 2 - extra whole digit articulating with MC/P

Type 3- extra whole digit articulating w EXTRA MC

 

Crossed polydactyly - invovles hand and feet

Mixed polydactyly - invovles both ulnar/radial

33

What is central polydactyly and treatment

  • duplicate central digit, most ofeten assocaited with SYNDACTYLY
  • most common ulnar digits
  • frequent bilateral +/- feet
  • Treatment
    • carry out normal syndactyly release, recon DTML

34

Duplication - Post axial polydactyly

 

What is the definition, epidemiology, classification, treatment

  • Def: duplication of little finger
  • Epidemiology
    • cited as most common congenital hand anomaly
    • most common polydactyly
    • frequently bilateral
    • 8x more common in africans
    • can be isolated, AD or syndromic, AR
  • Classification - McKusick, Stilling, Temtamy
    • TYpe A - well developed digit
    • Type B - rudimentary digit (no bone articulation)
  • Treatment
    • after 6months
    • Goals: remove extra digit, rebalance ST/jt/tendons
    • Type A: excise ulnar-most digit, reattach UCL/hypothenar muscles

35

Duplication: Ulnar dimelia

What is the definition, clinical presentation, treatment goals and procedure

  • Def: charcaterized by absent radius and two ulnae, 7-8 digits and no thumb
  • Clinical presentation
    • usually soradic, unilateral
    • if inherited, bilateral +/- associated with fibular dimelia
    • stiff elbow, flexed wrist, poor pron/sup
    • duplicated ulnar carpal bones
    • stiff IP joints
    • bifucated flexor tendons shared by digits
    • 2 ulnar arteries joined by one superficial palmar arch
  • Treatment goals
    • correct elbow stiffness
    • improve pronation/supination
    • improve wrist stiffness
    • create thumb and webspace
    • remove multiple digits
  • Treatment steps
    • preaxial ulna resected subperiosteally at elbow joint
    • tendon lengtheing of flexors and transfer to extensors
    • pollicization of pre-axial digit
    • amputation of other excess digits

36

Overgrowth: Macrodactyly

What is definition, clinical presentation, DDX, associated syndromes, treatment

  • Definition: overgrowth of all structures in digit 
  • Clinical presentation
    • usually single digit or 2-3 digits adjacent to one another
    • may be static (large at birth) or progressive (more commonly, faster gorwth rate compared to other digits)
    • Unilateral, right
    • most common index, long
  • DDx
    • macrodactyly, hemihypertrophy, Vascular malformation, lymphatic malformation, neurofibromatosis, proteus
  • Associated syndromes
    • neurofibromatosis, lipomatosis
    • Maffucci, Ollier (high maignant potential)
    • Klippel trenaunay
    • Proteus (hamartomatous dysplasia, hemihypertrophy, feet/hand macrodactyly, parotid/ovarian tumor, CLVM)
  • Treatment
    • Ray amputation (preferred if non-fx)
    • debulking (not effective)

37

Congenital ring syndrome

What is the etiology, clinical presentation, associations, classification, treatment

  • Etiology
    • external - amnion band constricting limb
  • Clinical presentation
    • all sporadic
    • most commonly afftect index/long fingers
    • proximal tissues form the band are normal
  • Assocaited with Oligohydramnios, prematurity
  • Classification: Patterson
    • ​Type 1 - shallow band
    • Type 2- deep band with distal lymhedema
    • Type 3 - distal fusion of structures (acrosyndactyly)
      • A- fusion of tips
      • B- fusion of tips and incomplete web formation
      • C- just fenestration in web
    • Type 4 - intrauterine amputation
    • Type 5 - mixed
  • Treatment
    • Type A: for cosmesis - excise and release band w zplasty. Need to monitor for acute edema/impedending tissue loss
    • Type B : ass. w edema, neuro deficit;  release band w zplasty, consider staged doing 1/2 at a time
    • Type 3 - treat as acrosyndactyly, earile than 12m

38

Generalized skeletal abnormalities: Madelung's deformity

What is the definition, presntation, assocaitions, xray findings, treatment

  • Def: congenital abnormal groth of radius physis at the volar ulnar aspect of the distal bone
    • = dorsal subluxation of ulna
    • = volar ulnar subluxation of carpus
  • Presentation
    • usually in adolescence with wrist pain/stiffness, limited supination, extension
    • females, sporadic, bilateral
    • P/E: carpus volar ulanr, ulna dorsally subluxed, limited supination, limited finger extension/EDC rupture, +/- CTS
    • Xray: Radial volar angulation of radius and ulna dorsal subluxation
  • Assocaited w: 
    • kienbock, achondroplasia, ollier, MPS
  • Treatment
    • tx at skeletal maturity if possible adn symptomatic
    • jt leveling procedure
    • partial/total radiocarpal arthrodesis
    • radioulnar arthrodesis

39