• Spiral fractures are a result of torsional forces; axial loading compression cause oblique fractures; tension/three point bending cause transverse fractures

Distal phalanx fractures:

• Open fractures do not require antibiotics 
• Tuft fracture: splint 14 days
• Shaft fracture: splint vs K wire
• Mallet finger: DIP typically remains concentrically reduced if <43% of joint surface involved; >52% consistent subluxation
• Treatment: surgical treatment recommended if >1/3 articular surface is involved
• Conservative treatment with DIP in extension and PIP free
• Complication: for every 1mm length in extensor tendon –> extensor lag 25 degrees; skin complications if closed
• Extension block pinning
• Seymour Fractures: physeal fractures of distal phalanx with interposition of proximal nail matrix –> requires open reduction –> remove nail –> remove interposed germinal matrix matrix –> splint (or K wires)
• Always an open fracture
• Jersey finger: avulsion of FDP from DP, most commonly of ring finger, type 1 retracts to palm (repair in 2 weeks), II retracts to PIP to A3 pulley (repair in 3 months), type III retracts to A4 pulley can be repaired at any time even after 3 months — ORIF–with screws or wiring

Middle phalanx fractures

• London classification –> for classification of fractures extending into DIP joint

• I: (non displaced unicondylar) and can be treated by orthosis x 3 weeks –> buddy taping 2-3 weeks
• II: K wire or screw fixation
• III: reconstruction difficult.
• Shaft fractures: stable fractures after reduction may be treated closed (3 weeks orthosis and then buddy taping 2-3 weeks)
• Acceptable alignment includes no clinical malrotation and no angulation >10
• Best evaluation of rotation is in full flexion 
• Oblique fractures need K wire or screw fixation (decreased ROM)
• Dislocation PIP: Rotary volar dislocations or any volar dislocation: of PIP typically irreducible, occurs after partial rupture of volar plate, collateral, and accessory collateral, condyle can become entrapped bt central slip and lateral band and buttonhole –> lateral band fibers –> repair includes central slip and lateral band repair(divide transverse retinacular ligaments)–> PIP in extension
• Dislocation with PIP condylar show, FDP typically involved- open must block irrigate and divide A3 pulley so condyle can move beneath flexor tendons  –> dorsal extension blocking
• Buddy taping used for PIP joint collateral ligament injury
• Dorsal Dislocation of PIP: (distal is dorsal) FDP, volar plate can block  reduction

Fracture dislocation of PIP

• Anatomy: Hinge joint 100-110 motion. 
• Dorsal PIP dislocation: 
• Assessment: classified by fracture configuration and stability (stable vs unstable) 
• Dorsal fracture dislocations are more stable in flexion and unstable in extension
• Concentric reduction of the joint achieved with 30 degrees flexion or less and those with less than 20% articular involvement of middle phalanx base are considered stable
• 30-50% articular surface or requiring increased flexion are described as tenuous and those with >50% articular involvement are unstable due to collateral being avulsed off of middle phalanx
• Radiographs/fluoroscopy are used to assess: radiographic V sign on lateral results from dorsal subluxation of the middle phalanx
• Treatment options: goal is for concentric reduction of PIP with good gliding motion

• Extension block splinting and pinning: PIP joint that is stable in <30 degrees flexion
• External fixation and dynamic traction: unstable or comminuted PIP dislocation fractures with loss of dorsal cortex, comminuted middle phalanx fractures etc
• ORIF: large partial articular fractures with minimal or preferable no comminution (concern for stiffness and loss of reduction)–>> need dorsal lip to be intact because it is a dorsal to volar surface
• Volar Plate Arthroplasty: for fractures less than 50-60% of the articular base of the middle phalanx
• Hemi-hamate arthroplasty: aims to reconstruct the volar buttress of the middle phalanx with an autologous osteochondral graft from the dorsal distal hamate –> for >50% articular surface
• Most common complication is arthrosis
• Delayed treatment involves surgical capsulectomy (collateral ligaments, volar plate, capsule, check rein ligaments
• Arthroplasty:  post traumatic degeneration of PIP joint in radial digit; arthrodesis recommended for same condition of ulnar digit
• Volar Dislocations: central slip injury common –> lack of recognition can lead to boutinniere deformity
• rare and usually occur as result of axial load with a palmarly directed force –> usually includes dorsal fracture at base of middle phalanx

• Think injury to central slip, may also need to repair lateral bands
• <25% articular surface then splint in 0; >25% needs ORIF or pinning
• Can be fixed by CRPP, ORIF, soft tissue reconstruction (for chronic injuries). Requires static splinting at 0. If joint is congruent may consider splinting alone
• With gentle traction, the MCP and PIP joints are held in flexion. This allows for relaxation of the volarly displaced lateral band (which can be impede reduction), allowing it to be freed up from the lateral condyle. This may then allow for successful reduction
• Central slip may also be impinged

Proximal Phalanx Fractures

• Anatomy: Angulation from fractures is always volar- proximal fragment is flexed by interosseous attachments while distal fragment is extended by the extensor central slip resulting in PIP extension lag –> 1mm of bone tendon discrepancy translates to 12 degrees extension lag
• Nonsurgical Treatment: nondisplaced closed fractures –> buddy taping and early ROM. Acceptable alignment includes at least 50% apposition, no malrotation (based on full flexion), less than 15 degrees sagittal or frontal plane angulation –> full ROM
• Reduction maneuver- digital traction –> flexion of MCP to 70-90 –> short arm dorsal block to hold MCP in flexion and IP extension. Only immobilize for 3 weeks. Early AROM of PIP will help maintain reduction by tension band effect
• Operative Treatment: unstable or nonreducible fractures (oblique, spiral commimuted)
• Type of Fracture:
• Base Fracture–> eaton belsky technique (flex at MCP and pin through MCP)
• Dorsal comminution most common cause of instability
• Acceptable sagittal plane angulation 25 degrees
• Non-op–> extension block orthosis; OP K wires vs ORIF
• Neck Fracture
• More common in children; most common is dorsal displacement
• K wires for partially displaced; complete ORIF
• Shaft Fracture
• Non op–> extension block orthosis; unstable percutaneous K wires or ORIF
• Comminuted may need ex fix
• Transverse K wires or ORIF
• Head Fracture
• Unicondylar (oblique volar, long sagittal, dorsal coronal volar coronal) –> usually unstable
• If stable may use orthosis or K wires
• Displaced needs K wire and ORIF
• Bicondylar needs ORIF with plate vs screw vs oblique tension band 

Complications:

• Loss of motion
• Malunion
• Nonunion

 

• Metacarpal fractures: joint is hinge joint for thumb, condyloid for index/small fingers
• Cam effect: construct that translates rotary motion into linear motion (flexion of MP puts stretch on collateral ligaments)
• Dorsal wounds over metacarpal fractures almost always open; volar wounds may not communicated
• Imaging: 
• PA, lateral, oblique
• Brewerton for metacarpal head
• 30-45 oblique for cmc
• Roberts view for thumb CMC
• CT scan may be useful to inconclusive, complex CMC/metacarpal head
• Metacarpal Head Fractures:
• No degree of articular displacement is acceptable
• ORIF via dorsal incision with central split of extensor or release and repair of sagittal band—> capsule incised and peeled off MC head and proximal phalanx
• Usually fixed small screws in collateral recess, headless screws, K wires
• If severely comminuted consider ex-fix or MCP joint replacement (arthrodesis or arthroplasty last options)
• Metacarpal Neck Fractures
• Metacarpal neck fractures: occurs when axial load applied to clenched fist, apex dorsal angulation because intrinsic muscles lie volar
• Acceptable apex dorsal angulation 
• Index: 10°-15°
• Middle: 10°-15°
• Ring: 20°-40°
• Small: 20°-60°
• Deformity from fracture: loss of appearance of the knuckle, bump in the palm (pseudoclawing; MCP hyperextension and PIP flexion requires reduction)
• Treatment: 
• Cast immobilization- MCP 70-90 to stretch the collaterals (PIP free); should cast for 3-4 weeks
• Jahss maneuver: 90 MCP flexion –> dorsal pressure through proximal phalanx while stabilizing metacarpal shaft
• Operative Treatment: (any malrotation, unacceptable angulation)
• CRPP with MCP flexed to prevent collateral contractures (anterograde or retrograde though collateral recess); should encourage PIP motion; remove pins at 4 weeks
• Metacarpal Shaft Fractures: 
• Acceptable Angulation: Index <10, middle <10, ring 20, small 30. No malrotation acceptable
• Remember that ring metacarpal shaft is the smallest
• Treatment (as above) casting or ORIF. Can include plate or IMN. Non compressing for oblique, compression for transverse
• Lag screws need diameter of fx 2x the diameter of bone
• Miniplate great for transverse fractures 
• Nailing can be used for either, traditionally used for transverse fracture
• Reduce (apex dorsal so volarly directed pressure with prox phalanx flexed, traction, watch your angulation)
• Metacarpal Base Fractures:
• Extra-articular- treat similar to metacarpal fractures
• K wires place into carpus through CMC; T plates
• Intra-articular needs anatomic reduction –> consider CT scans –> ORIF with multiple K wires vs lag screw fixation
• Additional X ray views include AP view with forearm pronated 30 degrees (can show 5th CMC), lateral with 30 degrees (again for 5th CMC)
• Thumb Extra-Articular Metacarpal Base Fracture (metaph/diaphyseal junction)
• Apex dorsal angulation with adduction, flexion, and supination of distal fragment
• Acceptable angulation 20-30 (angulation causes decreased thumb web space and MCP hyperextension
• Transverse thumb base metacarpal

• Can accept up to 30 degrees of angulation for nonoperative treatment
• Pin of angulated
• Reduction:TAPE longitudinal traction/abduction/pronation/extension –> should assess with flouroscopy –> best view is true lateral of metacarpal
• Treatment: closed reduction with K wires through CMC for 4 weeks
• MCP dorsal dislocation: (described distally) index finger most commonly involved (so dorsal dislocation of finger and MC head volar); small also common
• Mechanism is usually forced hyperextension (also check for DIPJ stability)
• Complex if cannot be reduced closed (nonreducible likely to have volar plate, FDP, lumbricals)
• Present with MCP extension and flexion of PIP/DIP puckering of skin can be seen at surface of MCP
• Studies reveal flexors go ulnar to metacarpal head in EVERY case, radial digital nerve was superficial (risk with volar approach)
• MCP dorsal dislocations: small finger flexor tendons/lumbricals on radial side and ADM/FDM on ulnar side; index finger- lumbrical on radial side and Flexor on ulnar side
• Division of volar plate typically needed for ALL reductions that are required open (if you see sesamoid interposed than volar plate is stuck)
• Method: closed reduction is attempted with wrist flexion (relax flexors) gentle extension, and push down on dorsal proximal phalanx(avoid longitudinal traction) as this can create complex dislocation by allowing volar plate to interpose between heads

• The lumbrical (radial) and flexor tendon (ulnar) can also create a noose if longitudinal traction is applied
• Open reduction can be approached dorsally or volarly. 
• MCP dorsal dislocation of thumb: typically can be closed reduced –> gentle hypertextension of MCP with direct pressure on dorsal base of the proximal phalanx (disrupts volar plate, dorsal capsule, portions of collateral ligaments)
• FPL and thenar musculature can trap the metacarpal head like a noose –> can give digital block and provide wrist flexion to help
• MCP volar dislocations: rare and no consensus of treatment –> usually no interposed structures with these injuries and closed reduction successful. 
• CMC Joints:
• Thumb CMC: 
• Anatomy: “horse saddle” joint; 16 ligaments supporting the joint (anterior oblique and dorsal radial most important); dorsal capsule confluent with extensor/abductor mechanism
• Thumb CMC Fracture Dislocation (Bennett Fracture)–> 2 components volar fragment which is small and attached via AOL and trapezium and second fragment attached to metacarpal shaft –> migrates proximally, dorsally, and radially (via APL AdP, EPL EPB)(apex dorsal angulation)
• Reverse bennett: fifth metacarpal base with dorsal subluxation, deforming forces include FCU/ECU, ADM; reduce by longitudinal force and volar traction on MP base K wire to Metacarpal and hamate, can plate through ulnar incision, if stiffness results (arthrodesis)
• Treatment: CRPP or ORIF
• Dapper- distract, radial pressure at base (abduction of shaft), pronate, perfect reduction
• CRPP–> reduction as described (traction/pronation and dorsal pressure) followed by 1 wire from large to small fragment and 1 from large fragment to trapezium; transmetacarpal wires also option
• Orthosis for 6 weeks; pins for 4-6 weeks (PROM at 6 weeks strengthening 8)
• Rolando Fractures: comminuted intra-articular fracture T or Y type (osteosynthesis with plate vs ex fix if very comminuted)
  MCP Joint: 
• Anatomy: (static and dynamic (intrinsic muscles) stabilizers)
• UCL consists of proper and accessory collateral ligaments –> thick band measuring 4-8mm wide and 12-14mm long
• Originates from dorsal-ulnar aspect of MP head proximal volar part of proximal phalanx
• Accessory UCL is contiguous and just volar to proper UCL and inserts on volar plate of MCP – more superficial
• RCL consists of proper and accessory collateral ligaments –> thick band measuring 4-8mm wide and 12-14mm long
• Originates dorsoradial and attaches on lateral tubercle of proximal phalanx
• APB most superficial layer –> aponeurosis –> FPB
• Sesamoids have metacarpal attachment that are important for stability. Sesamoids are aligned in parallel to metacarpal head but with disruption parallelism is lost
• Adductor pollicis is primary dynamic stabilizer to MCPJ and attaches to proximal phalanx and ulnar sesamoid–> likes volar to axis of rotation
• Injury: Acute abduction (radial directed) injuries tear UCL and are referred to as “skiers thumb” (acute) and “gamekeeper’s thumb” (chronic)
• Adduction injuries for RCL
• Examination: the metacarpal is stabilized and radially directed force is applied to the proximal phalanx. Performed in extension (accessory)  and 30 degrees flexion (proper).
• 20-45 **35 degrees of angulation is diagnostic of complete ligament injury (in extension) – both accessory and proper, in flexion (proper)
• 10-15 difference in laxity on contralateral side is diagnostic of complete tear
• Make sure the thumb is neutral- false positives and negatives are appreciated when thumb is pronated or supinated
• Radiographic Examination: 2mm of radial translation of proximal phalanx on metacarpal head consistent with complete disruption of both accessory and proper UCL. 
• Advanced imaging: MRI/ ultrasound can be used to diagnose UCL injuries (MRI more sensitive and specific)
• Treatment: Grade 1/2 injuries (strain and increase of laxity) of RCL/UCL treated by immobilization for 4-6 weeks. Concern in partial tears in RCL for partial tears –> most advocate RCL repair
• Grade3-surgical repair or reconstruction depending on chronicity. **RCL tears AdP and EPL may cause excessive ulnar deviation and persistent instability in RCL tears
• UCL is typically avulsion off of the proximal phalanx; RCL is equal avulsion from the metacarpal and proximal phalanx (but more proximally if asked)
• Stener lesion: UCL avulses and retracts proximally, interposed adductor aponeurosis precludes primary healing , UCL will not heal properly without contact at avulsion site

Mechanism: hyperabduction or extension of thumb at MCP

• Repair is typically suture anchors/transosseous wiring/ vs internal brace
• Reconstruction UCL: usually done at 3-6 weeks due to poor outcomes of repair only
• Reconstruction RCL- treated with similar reconstruction techniques (repair, advancement of APB, free tendon grafting)
• APB can be left attached distally and inserted onto the radial side of the metacarpal head proximally

Thumb MCP Dislocations: majority dorsal, hyperextension 

• Closed reduction usually possible –> interposed tissues can block (volar plate, FPL, sesamoids, check collateral stability

CMC Joint: least stability because of its biconcavoconvex saddle shape. 

• Anatomy: 4 main ligaments- anterior (volar) oblique- deep and superficial parts, dorsoradial, intermetacarpal, and posterior oblique (in total 16 ligaments)

• Volar ligament AOL primary stabilizer and attenuation or disruption is important in subluxation or dislocation

• Deep ligament taut in abduction and extension
• Superficial taut in pronation and extension
• Dorsal ligament is the PRIMARY LIGAMENT strongest ligament of thumb (posterior oblique, dorsoradial and dorsal central) and are predictable/stout. Need to be torn for dorsal subluxation of the thumb and may be most important for thumb stability (dorsal stability)
• Radiographic Examination:
• TMC hypermobility radiographs with dynamic stress view (accentuates radioulnar subluxation of the metacarpal –> bilateral basal joints with pressure exerted simultaneously by the radial thumb tips against each other
• Dorsovolar laxity can be tested by opposing thumbnails on true lateral view and is more functionally relevant (translates to instability with lateral pinch)
• Roberts view (true view of CMC, true lateral, thumb stress)
• Advanced Imaging: Ultrasound can be used to identify AOL ligament

Miscellaneous: 

• Salter Harris
• Appropriate positioning of PIP joints for arthrodesis: index finger is 40 degrees
• MP joints

• Supracondylar fracture: occurs most commonly in patients 5-7 years of age, fall on outstretched hand –> risk of ischemia 

• Immediate closed reductoin needed (gentle traction and elbow flexion) –> followed by operative closed reduction if unsuccessful or ischemia persists
• If hand is perfused even despite pulse just observe
• Types of bone grafting: 
• Osteoconduction: refers of replacement of graft material through process of creep substitution (cortical grafts, calcium hydroxyapetite)
• Osteoinduction: stimulation of bone forming cells from surrounding host tissues (cancellous grafts, demineralized bone matrix, and cortical bone)
• Osteogenesis: autografts like cancellous, vascularized bone
• Noncritical bone defects <6cm can undergo autologous bone grafting (corticocancellous from iliac crest)
• Distraction osteogenesis may work if the bone has adequate stock on either side of fracture
• Most common wrist fractures: distal radius, scaphoid, triquetrum, lunate