Hand and Lower Extremity

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Blauth classification for thumb hyplasia: (can be associated with VACTERL, TAR, Fanconi anemia, Holt-Oram)  work up with renal ultrasound, echochardiogram, CBC, chromosomal breakage test)

  • I/II/IIIA are managed without index finger pollicization (all have stable CMC joint)
  • IIIB/IV CMC is unstable and absent and index pollicization is used

Amniotic Band Syndrome: constriction bands may range from skin impressions to annular bands that can cause autoamputation. If a constriction band is threatening a limb should excise the band (one or two stages)

Giant cell tumor of tendon sheath: most common benign neoplasm after ganglion cyst. Histologically appears of multinucleated giant cells, histiocytes, fibrotic material and hemosiderin deposition. Treatment includes surgical excision (this is defined as marginal excision).

Spiral oblique retinacular ligament reconstruction (SORL) is used for swan neck deformity. This recreates the function of the ORL by linking the DIP/PIP.

– the ORL arises from the flexor tendon sheath at the base of the proximal phalanx and fuses with lateral terminal extensor tendon (tight with PIP extension, lax with PIP flexion)

PIA flap (posterior interosseous flap) may be based reverse for soft tissue defects involving the dorsal hand, MP joints, first web space

– perfusion is based on retrograde flow through the posterior interosseous artery. Axis of Flap is marked from the lateral epicondyle to radial aspect of ulnar styloid (perfusion relies on intact communication of PIA with dorsal branch of AIA which is two cm proximal to ulnar styloid)  perforators are located between EDM and ECU

Flexor tendon repair: minimize handling of tendon, core suture should be placed 7-10mm from tendon edge, dorsal placement biomechanically adventagous.

Nail bed laceration: skin glue vs suture –L skin glue has been shown to be faster (only advantage), all other equivalent

Brachial plexus injuries: neurolysis, nerve grafting, nerve transfers should be performed within the first 6 months of injury. Free functioning muscle transfers or tendon transfers are reserved for patients who present >12 months.

– FFMT usually anastomosed to thoracoacromial artery and vein with uninjured nerve (spinal accessory or intercostal nerve)

Intrinsic plus positioning: 15-30 wrist extension, 70-90 MCP flexion, 0 flexion at IP joints

Lymphedema: treatment begins with conservative management including compression therapy, lifestyle modification, therapeutic exercise (surgical is used for refractory cases)

– staging: 0- clinically normal extremity but abnormal lymph transport on lymphoscintigraphy; 1: edema that improves with limb elevation; 2: pitting edema that does not improve on limb elevation; 3: fibrotic limb changes

Glomus tumor: benign mass that is painful and typically found underneath the nail. Symptoms include sensitivity to cold, paroxysmal pain (day or night), pinpoint pain (loves sign). Blood pressure cuff inflation causes decrease of pain distally (hildreth’s sign). Workup includes MRI. Treatment excision.

EMG/NCS: recovering nerve exhibits nascent potentials; appear several months after injury and are a result of axonal regeneration

– decreased motor unit potential amplitude, fibrillation potentials, positive sharp waves, decreased motor unit recruitment are findings in the setting of nerve injury and not indicative of recovery.

– nerve growth occurs 1mm a day, motor endplates degenerate 1% per week, maximum nerve growth is 13-18 inches

PIPJ dorsal fracture dislocations: <30% or less stable, 30-50 tenuous, >50 unstable. Fractures that require more than 30 degrees of flexion for joint congruity are considered unstable and require surgical management. <30 may undergo dorsal block splinting

Volkmann’s ischemic contracture: result of untreated compartment syndrome causing muscular necrosis and fibrosis. Trauma or pediatric supracondylar fractures can be a cause.

FDS, FDP, FPL, PT are most commonly affected (deep volar compartment)

Mild contractures: allow for full passive extension of the fingers with the wrist in flexion and can be treated with tendon lengthening and skin release

Moderate contractures: cannot passively or extensively extend the fingers with the wrist in flexion, but retain flexor function (treated with flexor pronator slide)
Complete loss of function or severe necessitates free functional muscle transfer

Hook of hamate fractures: can be seen in athletes, causes pain with grip, weakness, and can affect ulnar nerve sensation. Is frequently missed on Xray. Carpal tunnel views or CT scan can identify this, treatment is typically hook of hamate excision or ORIF

Obstetrical brachial plexus palsy: initially treated with observation as up to 70% of patients have complete or near complete recovery

Skin graft contracture: thinner grafts (STSG) undergo more secondary contraction as well as meshing

Hook nail deformity: caused by deficient bone support of distal nail bed, soft tissue deficiency or both. Correction includes release and shortening of nail bed that does not have bony support, or augmentation of distal soft tissue envelope

Random pattern flaps are described as transposition, advancement or rotation flaps. Z plasty is a transposition flap (incorporate noncontinuguous skin into defect by lifting the flap over normal skin for inset).

  • Advancement flaps recruit adjacent tissue
  • Rotation flaps move tissue around an axis

Mycobacterium abscessus: increased incidence in patients traveling to other countries for surgery, based on ineffective sterilization of surgical equipment or solutions (like quaternary ammonium solutions)

Brand Transfers (radial nerve palsy transfers): PL to EPL; FCR to EDC, PT to ECRB

Interossei attach to metacarpals; lumbricals arise from FDP tendon

Hypothenar hammer syndrome: conservative management first with CCB, smoking cessation, stellate ganglion block. If no resolution of symptoms should proceed with reconstruction of underlying etiology in this case, ulnar artery reconstruction

-remember DBI <0.7 is indicative of reconstruction and 0.5 is indicative of critical ischemia

Pediatric supracondylar fractures may cause median or anterior interosseous nerve injury although it will resolve with conservative management (typically)

– brachial artery or pulseless extremity warrants surgical exploration

– AIN innervates FDP of index and FPL (no sensation)

Sciatic nerve -> sural nerve, common peroneal, and tibial  tibial nerve branches into medial and lateral plantar nerves, and medial sural cutaneous nerves

– medial plantar artery found between abductor hallucis and flexor digitorum brevis

Scapholunate injury: clenched views of an acute dynamic injury will reveal gap >2-3mm. Sub acute/chronic/ or acute injuries with attenuation of secondary stabilizers will cause a lateral radiograph to reveal a scapholunate angle >60 degrees

– after secondary stabilizer attenuation and fixed changes on xray  the wrist will begin to go into DISI or dorsal intercalated segment instability with the lunate EXTENDED and the scaphoid FLEXED (lunate still attached to triquetrum)

– arthroscopy is considered the gold standard for diagnosis of scapholunate and other intercarpal ligament injuries (think drive through test)

Intrinsic musculature of the hand: causes flexion at MP; extension at IP joints (intrsincs are volar to MP and dorsal to IP joints)

– intrinsic tightness: if passive flexion of IP joints decreases with extension of MP joints; passive flexion of IP joints increases with MP flexion

Free fibular dissection: lateral compartment  anterior compartment (EHL encountered prior to interosseous septum- remember that TA is medial to plane of dissection for fibula flap), -> deep posterior compartment

– peroneal nerve is at risk as it wraps around the fibular neck at the proximal osteotomy junction

Carpal tunnel syndrome: CSI is considered in patients with <3 months duration of symptoms and mild CTS on NCS

TMR: benefits of TMR in UE amputees include improved control of myoelectric prosthesis for transhumeral amputees and improvement of residual limb pain

SCC in immunocompromised patients should be excised with at least 6mmto 1cm margins and extending into subcutaneous tissues

-most common malignant tumor of the hand

Latissimus dorsi: donor site morbidity includes shoulder weakness with ADDuction, extension, and internal rotation

Apert syndrome: associated with craniosynostosis, mid face hypoplasia, and complex syndactyly of hands and feet

Perilunate dislocation: mechanism includes wrist extension, ulnar deviation, and intercarpal supination

Mayfield classification: disruption of SL and RSC  LC joint  LT joint  dislocation of lunate from its fossa and disruption of DRC ligament

SHORT radiolunate ligament is likely still attached which gives it the spilled teacup sign

Sagittal band injury: responsible for maintaining the position of the extensor tendons dorsally over the MCP joint, when band is ruptured the extensor can migrate causing difficulty to initate extension (but can hold extension when placed). Treatment is immobilization or surgical

Flexor tendon rehab protocols: use dorsal forearm based splint, and early active range of motion protocols demonstrate better functional outcomes without significant increase in early rupture rates (need at least 4 strand core suture for early active ROM)

PIN syndrome: seen commonly in rheumatoid arthritis patients with proliferative synovitis of the radiocapitellar joint. Will reveal loss of active extension of thumb, finger will maintaining wrist extension in radial deviation and complete tenodesis. Innervates all extensors of wrist except ECRL

Dupuytren’s: cord responsible for neurovascular bundle displacement is the spiral cord (consists of pretendinous band, spiral band, lateral digital sheet, and grayson’s ligament)

  • central cord can give MP/PIP contractures
  • natatory cord web space
  • retrovascular cord responsible for DIP contractures

Bilateral carpal tunnel syndrome carries wrist for amyloid deposition and amyloidosis  can be diagnosed by small incision during carpal tunnel release and is identified by congo red stain

FDS anatomy at the carpal tunnel: middle and ring are superficial and stacked over the index and small FDS tendons  FDP is side by side and dorsal to both. Median nerve is located between the superficialis and profundus MSK units at this level

Burn patients with circumferential burns can develop compartment syndrome requiring fasciotomy over escharotomy (remember 5 Ps pulselessness, paresthesia, pallor, pain with passive extension, paralysis)

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