Classification sin Hand Surgery

EMBRYOLOGY of the Upper Limb Weeks 4 to 6 The critical APICAL ECTODERMAL RIDGE exerts an inductive influence on the limb mesenchyme that promotes growth & development of the limbs.  Factors play a vital role in this process. The upper extremity, with pronated forearms begins to rotate externally.    Developmental disturbances during this period gives rise to major congenital malformations. Early suppresion of limb development causes AMELIA (complete abscence of a limb); Late suppression causes MEROMELIA (partial abscence). Weeks 7 to Birth By week 7 the ten finger rays appear and continue to differentiate till week 12 - 13 when the hands appear.  The fingers develop as a result of cell death in the tissue between the digits (failure of this causes syndactyly).  INTERNATIONAL CLASSIFICATION (FDD.OUC) Failure of Formation Transverse Arrest / Aplasia Amputations: arm, forearm, wrist, hand, digits Longitudinal Arrest Phocomelia: complete, proximal, distal Radial deficiencies (radial club hand) Central deficiencies (cleft hand) Ulnar deficiencies (ulnar club hand) Hypoplastic digits Failure of Differentiation A. Synostosis: elbow, forearm, wrist, metacarpals, phalanges B. Radial head dislocation C. Symphalangism D. Syndactyly Simple Complex Associated syndrome E. Contracture i. Soft tissue Arthrogryposis Pterygium cubitaIe Trigger digit Absent extensor tendons Hypoplastic thumb Thumb-clutched hand Camptodactyly  Windblown Hand ii. Skeletal Cleinodactyly Kirner's deformity Delta bone Duplication (polydactyly) A. Thumb (preaxial) polydactyly B. Triphalangism/hyperphalangism C. Finger polydactyly Central polydactyly (polysyndactyly) Postaxial polydactyly Overgrowth A. Macrodactyly Undergrowth Constriction bands Generalised skeletal abnormalities  Madelungs deformity Thumb anomalies (Hypoplastic thumb) Blauth Grade Description Treatment I Short thumb, hypoplastic thenar muscles Augment intrinsics II Grade I + Adducted MPJ Soft tissue Z-plasty III Deficient metacarpal Abducted thumb Augment/ bone graft/pollicisation IV Floating thumb Pollicisation V Absent thumb Pollicisation   Lichtman Staging: Stage 1        Normal architecture & density, may see a linear compression # (Bone scan & MRI diagnosis) Stage 2        Increased density, normal architecture & outline; cysts Stage 3               collapse & fragmentation    collapse & fragmentation Stage 3A    No carpal collapse Stage 3B    Carpal collapse (prox. migration of capitate) Stage 4        OA Radiograph of Keinbock's - Note Negative ulnar variance Classification   It is important to distinguish the intra-articular fractures (Type I [Bennett's] + II [Rolando's]) from the extra-articular (III + IV) fractures, as the extra-articular fractures can be managed adequately with non-operative management Up to 30° of angulation of the 1st metacarpal base can be accommodated due the large ROM at the trapezio-metacarpal joint Classification (Mayo) Instability may be static or dynamic Carpal Instability Dissociative (CID) Relates to instability between individual carpal bones of the same row Carpal Instability Non-Dissociative (CIND) Relates to instability between carpal rows or transverse osseous segments, and can be caused by ligament injury or bony fracture (or both) Axial instability Involves a longitudinal force of disruption resulting in either dislocation or fracture dislocation Trans - if pathway of force is through a bone Peri - if pathway of force is around a bone Carpal Instability Complex (CIC) Several patterns exist which are a combination of CID and CIND lesion It is better to describe the individual components of these injuries as it is a guide to treatment Most frequently represented by perilunate injury Mayfield classified these in 4 stages: I scapholunate ligament injury II capitolunate ligament injury III lunotriquetral ligament injury IV dislocation of the lunate Carpal Injury Adaptive (CIA) Secondary changes in the carpus, which results from a non-union or malunion of the distal radius or carpal bones Dorsal Intercalated Segment Instability (DISI) When the lunate is rotated dorsally and the scapholunate angle is greater than 70º This is a description of the deformity but does not describe the pathological process Causes: SLL injury, scaphoid #, Keinboch’s and perilunate injury   Volar Intercalated Segment Instability (VISI) When the lunate is flexed and the scapholunate angle is less than 30º Much less common than DISI Most commonly caused by LTL injury Treatment CID Scaphoid fracture or non-union (can lead to SNAC) treat # or malunion Scapholunate ligament injury (can lead to SLAC) [Case Study] Acute Early open repair + K-wire stabilisation up to 3 weeks Delayed open repair can be performed up to 6 months Repair is by either direct suture, pull through sutures or suture anchors Chronic Bony procedures - scapho-trapezio-trapezoid fusion (STT) Soft tissue – dorsal capsulodesis (Blatt procedure) or FCR tenodesis (Brunelli Procedure)  Established Scapholunate advanced collapse (SLAC) Scaphoid excision and 4 corner fusion (capitate, hamate, lunate, triquetrum) Proximal row carpectomy Radial styloidectomy Wrist denervation (division of the anterior and posterior interosseous nerves at the wrist) Lunotriquetral ligament injury Rarely recognised acutely but if so then acute open repair of the ligament Lunotriquetral fusion FCU tenodesis Acute perilunate dislocation Immediate closed reduction followed by open repair of the ligaments via dorsal approach CIND Acute – direct repair of the ligaments CIC Treat the individual components of the injury CIA Normally related to radial malunion therefore perform a corrective distal radial osteotomy  CLASSIFICATION (Herbert) TREATMENT Stable non-displaced fractures POP cast immobilisation Type of cast immobilisation Below elbow cast – No need to include the thumb Position of wrist Ulnar deviation will distract the fracture, therefore this must be avoided Neutral in AP plane Moulded into the palm Duration 8 weeks Re-examine and X-ray at 8 weeks out of plaster If still tender then treat in cast for a further 4 weeks At 12 weeks leave free regardless of whether there is tenderness or not Re-X-ray at 6 months   Operative treatment Indications Trans-scaphoid perilunate dislocations Displacement of more than 1mm in any direction SEQUELAE OF SCAPHOID FRACTURES 1. Delayed union >4 months 2. Non-union Leslie and Dickson 5% Dias et al 12.3% 3. Malunion scaphoid may heal in a flexed position "hump back" deformity 4. Avascular necrosis - See eHand Images 5. DISI 6. Scaphoid Non-union Advanced Collapse (SNAC) Takes from 5-10 years to develop in most cases but can take up to 20 years loss of carpal height SNAC I radioscaphoid (RS) OA Radial styloidectomy Care must be taken to preserve the radiocarpal ligaments SNAC II RS OA + scaphocapitate (SC) OA Partial scaphoid excision (distal pole) Proximal row carpectomy All results are better with larger proximal pole fragments Proximal pole excision or prosthetic replacement has been universally abandoned because of carpal instability SNAC III RS + SC + lunocapitate OA Scaphoidectomy plus 4-corner fusion What is the aim of treating non-union? Correct carpal kinematics To achieve union Reduce pain Increase function Reduce the risk of developing secondary degenerative changes Non-union: No OA or AVN ORIF - for undisplaced fractures Matti-Russe inlay grafts Interposition trapezoidal graft + screw fixation inserted after excision of the non-union Non-union: AVN present but No OA Matti-Russe inlay grafts ORIF Vascularised bone grafts Non-union: OA present but No AVN See SNAC (above) Salvage procedures Wrist Denervation Total wrist fusion Classifications 15 different Classification systems exist! 1. Frykman Descriptive only and does not include variables, such as direction and degree of displacement or comminution Group Group 1 and 2 Extra-articular fracture ± distal ulna fracture 3 and 4 Intra-articular fracture involving the radiocarpal joint ± distal ulna fracture 5 and 6 Intra-articular fracture involving the DRUJ ± distal ulna fracture 7 and 8 Intra-articular fracture involving the RC and DRUJ ± distal ulna fracture   2. McMurtry and Jupiter Group Group 1 2 parts: Barton #, Chauffeur #, Die-punch # 2 3 parts lunate and scaphoid fossae separate from distal radius 3 4 parts lunate fossa fractured into dorsal and volar fragments 4 5 parts or more   3. Melone Classification Sub-types of 4-part intra-articular fractures Gives some indication to treatment Type   1 Minimal comminution - stable 2 Comminuted - stable 3 Displacement of medial complex as a unit + anterior spike 4 Wide separation or rotation of the dorsal fragment + palmar fragment rotation Types 1 and 2: MUA + POP cast Type 3: MUA + K-wire/ External fixation Type 4: ORIF   4. Universal Classification 5. AO classification Comprehensive but has poor inter and intra observer agreement   Cause     Notes Treatment 1. Idiopathic                 2. Mechanical Malunion distal radius die punch injury of scaphoid or lunate fossa; 4 part #; pilon injury fuse scaphoid & lunate to distal radius; radio-lunate fusion; involvement of midcarpal jt. = proximal row carpectomy Scaphoid nonunion SNAC wrist limited wrist fusion = excise distal pole of scaphoid & fuse prox. pole to lunate to capitate (or ? radial styloidectomy?) Scaphoid malunion 'hump back' deformity = scaphoid united in flexed position; may be rotational malunion also; scaphoid does not support lat. column thus incr. load central & medial columns osteotomy risky Carpal bone #'s medial column injuries -> capito-hamate & hamo-lunate impaction     Kienbock's disease Arthrosis = Lichtman stage 4 prox. row carpectomy or wrist arthrodesis Preiser's disease AVN of scaphoid     AVN Capitate         Hamo-lunate Impaction 70% of people have a facet on the medial aspect of the lunate which can impinge on the head of hamate in full ulnar deviation; diagnosed arthroscopically Hamate head excision (arthroscopic) STT OA [Radiograph] ass. with chondrocalcinosis; pain on radial deviation of wrist; STT arthrodesis DRUJ OA from malunion distal radius #s; injury to sigmoid notch Sauve-Kapandji procedure [Picture] Carpal instability SLAC scaphoid excision & 4 corner fusion (capito-hamo-triquetro-lunate) Dorsal rim impaction syndrome from scapho-lunate interosseous lig. incompetence; diagnosed arthroscopically; precursor of SLAC & SNAC     Piso-triquetral OA causes loose bodies in wrist joint     3. Metabolic Gout         Pseudogout         4. Inflammatory RA         Psoriasis           Scapholunate Advanced Collapse (SLAC): common pattern of OA may be end-stage of scapho-lunate dissociation The structures maintaining scapho-lunate alignment fail from trauma or degeneration. Lunate extends & scaphoid flexes -> reduces carpal height Later proceeds to radio-carpal OA & lunocapitate & lunohamate OA Treat with scaphoid excision + 4-corner fusion (lunocapitate & triquetrohamate)   Souter staging- Stage Clinical Treatment 1 Acute synovitis medical Mx & splinting 2 Chronic synovitis Synovectomy 3 Specific deformation Reconstructive 4 Severe crippling Salvage   Vaughn-Jackson Syndrome = rupture of EDC of ring & little fingers due top attrition rupture from prominent ulna (caput ulna) & DRUJ synovitis DD= subluxation, PIN palsy, locked trigger finger 'Tuck sign' = synovitis tucks under the skin with movement. Rx.= Darrach for pre-rupture; tendon transfer (EIP to EDM) for rupture. Mannerfelt Syndrome = FPL rupture due to carpal irregularities or volar synovitis Rx. = IPJ arthrodesis A. Swan-neck deformity: Causes: 1. Long extensor overactivity a. MCPJ contracture b. mallet DIPJ c. extrinsic spacticity 2. Intrinsic overactivity a. intrinsic contracture b. intrinsic tightness 2ndry to MCPJ disease 3. Failure of PIPJ stabilisers a. volar plate insufficiency b. FDS insufficiency c. Generalised joint laxity Nalebuff Type Description Cause Diagnosis Treatment 1 PIPJ flexible DIPJ mallet Cannot Extend DIPJ with PIPJ passively flexed Fuse DIPJ     PIPJ volar plate/ FDS insufficient Can Extend DIPJ with PIPJ passively flexed Extension block splint 2 PIPJ flexion limited with MCPJ extended = 'locked swan-neck' Tight Intrinsics (~volar plate weak) Can flex PIPJ with MCPJ flexed (Bunnell Test) FDS tenodesis (hemitenodesis or sling) / volar plate advancement 3 PIPJ stiff, joint preserved   X-Ray - No articular/ bony changes MUA or dorsal soft tissue release 4 PIPJ stiff, joint changes   X-Ray - Articular/ bony changes arthrodesis   B. Boutonniere deformity Rupture of central slip of extensor tendon due to synovitis of PIPJ. Lateral bands dislocate in a palmar direction, being converted from extensors to flexors. Non-surgical treatment of little benefit & can reduce function. Deformity Treatment Mild (10-15deg.) Extensor tenotomy over centre of middle phalanx Moderate ((30-40deg.) Numerous soft tissue procedures with variable results, thus low tolerance for arthrodesis Severe (fixed) Arthrodesis - position ranging from 20deg. index to 45deg. little finger   RHEUMATOID THUMB Nalebuff Type Deformity CMCJ MCPJ IPJ Initiating feature Treatment 1 Boutonniere Abd. Flex. Hyperext. MCPJ synovitis Arthroplasty MCPJ or IPJ, +/- extensor realignment 2 Boutonniere & Swan-neck Add. Flex. Hyperext. MCPJ & CMCJ synovitis Arthroplasty MCPJ or IPJ, +/- extensor realignment 3 Swan-neck Add. Hyperext. Flex. CMCJ synovitis, MCPJ volar plate attenuation CMCJ arthroplasty 4 Gamekeepers Add.  Abd. - ulnocarpal lig. (beak) destruction Lig. reconstruction / MCPJ fusion 5   Neutral Hyperext. Flex. Stretching of MCPJ volar plate MCPJ fusion 6 Arthritis mutilans Short Unstable Unstable Bone destruction Fusion     Classification:      - Stage I:               - mild joint narrowing or subchondral sclerosis;               - mild joint effusion or ligament laxity;               - no subluxation and no osteophyte formation are present;               - treatment involves NSAIDS & immobilization (which involves splinting the thumb in abduction);      - Stage II:               - narrowing of CMC joint & sclerotic changes of subchondral bone;               - there may be osteophyte formation at the ulnar side of the distal trapezial articular surface;               - mild to moderate suluxation may be present (w/ the base of the first metacarpal subluxated radially and dorsally);               - treament: ligament reconstruction tendon interposition:      - Stage III:               - furthere joint space narrowing w/ cystic changes and sclerotic bone;               - prominent osteophytes are present at the ulnar border of the distal trapezium;               - moderate suluxation is present w/ the base of the first metacarpal subluxated radially and dorsally;                      - passive reduction may not be present;               - scaphotrapezial may show arthrosis, and there may be a hyper-extension deformity of the MTP joint;               - treament: LRTI;      - Stage IV:               - there is similar destruction as in stage III w/ respect to CMC;               - scaphotrapezial joint has evidence of destruction;               - CMC joint is usually immobile and often patients have little pain;               - treament options: LRTI;      ref:               Trapeziometacarpal osteoarthritis: Staging as a rationale for treatment.                    RG Eaton, SZ Glickel.  Hand Clin. Vol 3. 1987. p 455.   STAGING - Woodruff, 1998: Stage    Description    Management 1    Early palmar disease with no contracture    Leave alone 2    One finger involved, with only MCPJ contracture    Surgery 3    One finger - MCPJ + PIPJ    Surgery not easy 4    stage 3 + > one finger involved    Surgery prolonged & only partly succesful 5    Finger-in-palm deformity    consider amputation   Tendon Transfers - summary table Low injury (wrist) High injury (elbow) MEDIAN NERVE: Thumb Opposition (loss of FBP) (note thumb opposition is combination of flexion and adduction) Ring finger FDS transfer to APB via a pulley made in the FCU tendon at the level of the pisiform. [Picture] MCP +/or IP joint fusion     For index and middle finger flexion    FDP of index and middle finger sutured side to side to FDP of ring and little fingers, +/- ECRL tendon transfer to FDP for extra strength For flexion of IP joint of thumb -Brachioradialis transfer to FPL For thumb opposition -Extensor indices transfer to Abductor pollicis brevis   ULNAR NERVE: For Adductor pollicis and FPB (thumb opposition)     Absent FPB = Ring finger FDS transfer to APB via a pulley made in the FCU tendon at the level of the pisiform. [Picture].   If FPB working and adductor not = use extensor indices transfer through interosseous membrane to adductor pollicis  For loss of action of interrosei and ulnar 2 lumbricals    Split tendon transfers of FDS + /- EIP & EDQ, to radial dorsal extensor apparatus (tenodesis procedures) Or stabilise MCP joint with Zancolli capsulodesis where the volar capsule is tightened to produce slight flexion of MCP joint (not very successful).     +For loss of FCU - Use ECRL transfer for power   COMBINED MEDIAN & ULNAR NERVES: For function of the interrossei and lumbricals, to restore flexion of MCP joint and extension of IP joints - Brands ECRB graft with a plantaris graft to increase length, attached to insertion of intrinsics Thumb opposition - FDS (ring finger) via FCU pulley to EPL [Picture] Thumb adduction (pinch) - EIP to Adductor pollicis   very difficult problem For function of the long flexors & interrossei and lumbricals, to restore flexion of MCP joint and extension of IP joints - Zancolli Capsulodesis of MCP joints, ECRL to FDP, BR to FPL,  ECU (with free graft) to EPL   Thumb fusions   RADIAL NERVE: (Radial wrist extensors functioning:) wrist extension - Pronator Teres to ECRB MCP joint extension -  FCR / FCU to EDC or FDS to EDC extension and abduction of the thumb - PL rerouted to EPL  If radial nerve might still recover keep EPL in continuity and bring palmaris longus upward          Nerve conduction studies Evaluation of peripheral nerves & their sensory & motor responses anywhere along their course Stimulation of a peripheral nerve should evoke a contraction in the muscles it supplies (seen, palpated or measured electromyographically) Latency (t)= time between onset of stimulus & the response Amplitude = size of response Nerve Conduction Velocity (V) = d / t (d = distance between stimulating & recording electrodes) Motor Nerve: Recording electrode (cathode) placed over a muscle supplied by the nerve (over the 'motor point' = region where the nerve enters the muscle) Indifferent electrode is placed a few centimeters away Ground electrode placed over an inactive muscle nearby Stimulation site is where the nerve is superficial (eg. elbow) Stimulator is turned on until a clearly defined CMAP (compound motor action potential) appears = 'threshold' Stimulus is increased by 50% to 'supramaximal' ensuring complete activation of the muscle. A second stimulator is added, distal to the first stimulator & closer to the recording electrode. The segment velocity between the 2 stimulation sites is calculated: V(motor) = [d1-d2]/ [t1-t2] (where V(motor) = segment velocity in motor fibres; d1 is distance betw. first (proximal) stimulation site & recording cathode; d2 is distance betw. second (distal) stimulation site & recording cathode; t1 is latency betw. first (proximal) stimulation site & recording cathode; t2 is distance betw. second (distal) stimulation site & recording cathode) Motor nerve conduction test for Ulnar nerve above & below elbow Motor nerve conduction test for Ulnar nerve at wrist using ADM (from TeleEMG) Sensory Nerve: CNAP (compound nerve action potential) is measured (lower amplitude than CMAP) a uniquely sensory nerve must be chosen for the stimulation site V(sensory) = d / t  (where V(sensory) is the segment velocity in sensory fibres; d is distance betw. stimulation site & recording cathode; t is the average latency betw. stimulus & CNAP) Sensory nerve conduction test for Ulnar nerve across the wrist (from TeleEMG) Collision Studies Timing of NCS: Immediately after section of a peripheral nerve, stimulation distally will elicit a normal response for 18-72 hrs until wallerian degeneration occurs.  Absence of distal nerve motor conduction (CMAP) after 3-7 days excludes a neuropraxia type injury. Absence of sensory conduction (CNAP) after 7-10 days excludes a neuropraxia type injury. Therefore the ideal time for NCS after injury is 10-14 days after injury to discern neuropraxia from axonotmesis / neurotmesis. Neuropraxia will improve (incr. velocity & decr. latency) with repeated tests, while axonotmesis & neurotmasis will deteriorate Somatosensory Evoked Potentials (SSEP) = stimulate peripheral sensory nerves & measure on the scalp. For study of brachial plexus & spinal cord monitoring. Electromyography A needle electrode in the muscle is used to record motor unit activity at rest and on attempted contraction of the muscle Normal EMG shows no muscle activity at rest and a characteristic pattern on voluntary contraction Normal EMG Immediately after nerve section, EMG will be normal, although there will be no muscle response after stimulation of the nerve proximal to the nerve injury (CMAP) Within Between 5 and 14 days positive sharp waves consistent with denervation   Positive sharp waves of Denervation At between 15 and 30 days, spontaneous denervation fibrillation potentials are present   Denervation fibrillation potentials If denervation fibrillation potentials are not present by the end of the 2nd week this is a good prognostic sign. Evidence of reinnervation is when highly polyphasic motor unit potentials are detected at attempts at voluntary activity Denervation fibrillations in a muscle only tell you that the muscle is not innervated. It does not determine whether the injury is 2nd 3rd or 4th degree. Reinnervation potentials by the same token can be restored after regeneration of only a few motor fibres and does not necessarily mean a good return to voluntary motor control EMG Findings in Specific Conditions: Condition    Insertional Activity * Rest Activity ** Fibrillations ***  Sharp Waves Potentials++ Interference Normal Normal Silent No No Biphasic & triphasic Complete Neuropraxia Normal Silent No No No None Axonotmesis Increased Increased Yes Yes Large & longer polyphasic None Neurotmesis Increased Increased Yes Yes Large & longer polyphasic None Axonal Neuropathy Increased Increased Yes Yes   Incomplete Demyelinating Neuropathy Normal Silent No No Yes Incomplete Anterior Horn Disease Increased Increased Yes Yes Large polyphasic Incomplete Myopathy Increased Silent Yes Yes Small polyphasic Early *  Insertional Activity = needle is inserted into muscle or moved within muscle, there is a single burst of activity that usually lasts 300 to 500 ms; thought to result from mechanical stimulation or injury of the muscle fibers **  Rest Activity = differentiates neuropathic muscle atrophy from myopathic atrophy *** Fibrillations - are action potentials that arise spontaneously from single muscle fibers; usually occur rhythmically and are though to be due oscillations of the resting membrane potential in denervated muscles. Appears 3 - 5 weeks after the nerve lesion. Preceded by Positive Sharp Waves. ++ Potentials - number of phases (? action potentials); indicates collateral axonal sprouting; polyphasic = > 4 phases Belfast Regimen: (J. Hand Surg. 14B:383-391. 1989) At 48hrs post-op remove dressings & apply splint  Thermoplastic splint: wrist 20deg., MCP 70deg., 2/3 up forearm, straps on palmar crease, wrist & forearm.  First 6 weeks: Fingers- Every 2hrs.- [1] Passive flexion (2x/ individual finger)- [2] Active extension (2x/ mass action)- [3] Active flexion (2x/ mass). Thumb- Every 3hrs.- as above. After 6 weeks:  Remove splint & progress to active flexion of individual joints. 6-8 weeks: use hand, no heavy liting. 8-10 weeks: slowly incr. activity, stretches into extension, fine work. 10-12 weeks: Driving, heavier work. > 12 weeks: Full funtion (60% strength back at 16 weeks).   New Classification: CRPS type I (RSD)  the clinical findings include regional pain, sensory changes, allodynia, abnormalities of temperature, abnormal sudomotor activity, edema, and an abnormal skin color that occur after a noxious event. CRPS type II (Causalgia)  includes all foregoing features with a peripheral nerve lesion. Old Classification of RSD (Langford): Minor causalgia Purely sensory nerve to distal portion of limb Minor Tramatic dystrophy Most common type Shoulder hand syndrome Proximal trauma or painful visceral lesion (shoulder or neck injury, cervical disc, PU, MI, pancost tumour etc) Major traumatic dystrophy Trauma that produces swelling, redess, dysfunction eg crush injuries and colles fractures head the list Major causalgia Partial injury to a major mixed nerve in the proximal part of the extremity