Hand Flashcards

Question 1

Q

Index Ray Amputation?

Question 2

Q

When would you consider Replantation?

Answer

A

INDICATIONS

Often is personal and surgeon dependent (top three most accepted reasons)

Thumb

Multiple injured digits

Children

Single digit distal to FDS

Partial hand (through palm)

Bilateral amputations

Wrist or distal forearm

Elbow or above elbow (if sharply avulsed and ischemia time not prohibitive)

Question 3

Q

Contraindication

Answer

A

CONTRAINDICATIONS

• Absolute
o Coexisting serious injuries/diseases that preclude a prolonged OR

• Relative
o Patient factors

§ Severe medical comorbidity or multiple system trauma
§ Neuromuscular disorder affecting that extremity
§ Current or prior trauma to the amputated part/extremity § Mental capacity/uncooperative patient

o Injury-specific factors
§ Multiple level injuries
§ Severely crushed, burned or mangled
§ Ring avulsions type injuries
§ Extreme contamination
§ Single digit zone II amputation
§ Proximal forearm
§ Destruction of sensory end organs (eg. loss of palmar skin) § Prolonged ischemia time (especially muscle)

Question 4

Q

How do you examin for vessle damage?

Answer

A

Ribbon sign (“corkscrew”): Tortuous-appearing vessel from avulsion or traction injury

Red-line sign: Red streak along neurovascular bundle implying distal vessel damage

o Ribbon & red-line signs are poor prognostic indicators

Cobweb sign: Intraluminal fibrin threads/webs

Telescope sign: Lumen telescopes away from outer vessel wall and past cut edge

Terminal thrombus: Indicates vessel wall disruption or damage

Measles sign: Pinpoint (petechial) bruising along vessel wall

Sausage sign: Ballooning of vessel from thrombus

Question 5

Q

What would you do if no vessle flow?

Answer

A

Patient:

o Make sure the tourniquet is down, relieve tension/compression proximally

o Vitals: Temp/BP - Warm the patient/OR/irrigation,

Increase the IV fluids +/- increase BP
o Correct a metabolic acidosis

—-> Clotting o IV bolus 1500-2000u at clamp removal +/- 1000u q1h intra-operatively, +/- postop

Local:

o Remove any obvious clots

o Irrigate the proximal end with heparinized saline or 1:20 papaverine

o Resect past possibly unrecognized zone of injury

o Use a vein graft

Question 6

Q

What applications for vein graft?

Answer

A

Goals of the vein graft
o To bridge venous or arterial gaps
o To compensate for diameter discrepancies
o To create a Y-shaped junction to anastomose two vessels to one

Question 7

Q

How would you address the nerve gap?

Answer

A

If a gap is present

o Shorten the bone (even more)
o Nerve graft preferred option (donors: sural, saphenous, MABCn, LABCn, digital nerves) o Conduits (vein, polyglycolic acid)
o Nerve transfers
o Leave it and repair secondarily

Question 8

Q

How would you address venous drainage in amputated finger tip.

Answer

A

o Repair a volar vein (smaller, thinner)
o Create an AV fistula: one distal digital artery anastomosed to one proximal vein o Remove the nail plate, scratch it, and apply heparin-soaked pledgets
o Leeches
o Digital massage of the distal part

Question 9

Q

How would you classify ring avulsion injuries?

Question 10

Q

Systemic Complications of Replant?

Answer

A

systemic complications from myonecrosis, rhabdomyolysis and myoglobinuria following reperfusion

Question 11

Q

How would you plan your major replant repair?

Answer

A

DEBRIDEMENT

Extensive muscle debridement may be required to prevent myonecrosis and subsequent infection

Usually require a second look in OR at 48-72 hours to re-evaluate muscle and debride as necessary

BONY FIXATION

Rapid, stable fixation critical

Bone shortening to allow primary repair of median, ulnar, radial nerves

Dynamic compression plates and screws (better than pins/rods)

Crossed Steinman pins can be used across joints

ARTERIES

Usually performed immediately after bony fixation (almost always prior to veins)

Vein grafts usually needed

VEINS

• Beware systemic load of lactic acid, potassium, myoglobin and other toxic metabolites

o Allow veins to bleed out to prevent systemic complications, communicate with anesthesia
• Consider IV sodium bicarb (+/- mannitol, calcium carbonate) prior to releasing clamps on venous repair

MUSCLES/TENDONS

Try to repair most tendons primarily, can be difficult if the amputation is through the muscle bellies

In general, a healthy appearance and contraction of pronator quadratus with stimulation is an excellent prognostic indicator of forearm perfusion.

NERVES

Grouped fascicular alignment is important (these are mixed motor/sensory nerves)

If unable to coapt, tag and perform sural grafts secondarily

FASCIOTOMIES

Always indicated
o Volar, dorsal, mobile wad (lateral)) compartments of forearm
o Hand (10 total) – dorsal interossei x4, volar Interossei x3, thenar, hypothenar, adductor pollicus

Release carpal tunnel and Guyon’s canal

Question 12

Q

What are your post repant orders?

Answer

A

ROUTINE ORDERS

Elevate hand
Monitor digit (CTTC) q 1 h X 24 hrs
o Maintain temp digit >31C, or >2C difference from contralateral
o +/- pulse oximetry of digit
NPO x 24 hrs, then micro DAT, bedrest x 5 days with dressing intact
SC heparin (prophylactic dose)
Warm environment (ambient +/- warming blankets)
Proper hydration (monitor U/O)
Adequate analgesia including APS (brachial plexus block, sympathetic blockade)
No smoking or caffeine (for 4-6 weeks)
IV antibiotics peri-op (continue if being leeched – Septra, quinolone or 3rd generation cephalosporin)
1st dressing change at day 5 (and splint made then)
Hand therapy & social work (± Psych) to see prior to d/c

Question 13

Q

ASA action?

Question 14

Q

Heparin, LMWH, Leech Action?

Question 15

Q

Lido, Pap, Strep, tpa action?

Question 16

Q

Monitoring?

Answer

A

CCTT

Color, Cap refill, turgor, Temperarure

Question 17

Q

How would you discuss the immediate compliations of replatation?

Answer

A

Early

Anaesthetic complications
Usual postop complications
Vascular insufficiency (arterial or venous)
o Usually within 72 hrs, but may occur late ~ 10-14 days
o Possible salvage if promptly returned to OR, but do risk injury to other digits
Compartment syndrome, acute nerve compression syndromes
Infection
Bleeding/hematoma from systemic anticoagulation
Nightmares/acute post-traumatic stress disorder
Release of toxic metabolites from major limb replant
o Myoglobinuria and ATN
o ARDS
Acidosis
Hyperkalemia and cardiac problems

Question 18

Q

How would you discuss later complications of replant?

Question 19

Q

How would you discuss the outcomes of replantation?

Answer

A

OUTCOME

In a meta-analysis, survival rates for replanted digits were 91% with clean-cut mechanisms, 68% with crushing mechanisms, and 66% with avulsive mechanisms

Worse Outcomes with

o Crush/Avulsion

o Distal Phalanx
o Thumbs (more aggressive attempts at replantation)
o Smokers
o Male (related to being involved in crush/avulsion type injuries)
o Children (smaller vessels, increased risk of vasospasm, increased avulsion mechanisms, and more aggressive attempts at

replantation)
• In general, expect about 50% of previous function and 50% of previous sensation

o Nerve recovery is comparable to repair of isolated nerve injuries (50% get 2PD < 10 mm) o AROM is usually around 50% of normal

Question 20

Q

How would you classify nerve injuries?

Question 21

Q

Gram CTS Criteria

Risk factors?

Answer

A

(1) nocturnal numbness; (2) numbness and tingling in the median nerve distribution; (3) weakness and/or atrophy of the thenar muscles; (4) Tinel sign; (5) Phalen’s test; and (6) loss of two-point discrimination.41

Also:Threshold sensory tests such as Semmes–Weinstein monofilament measurements tend to be more sensitive for detecting early CTS than innervation density measurements.36Manual testing of abductor pollicis brevis muscle strength as well as grip and pinch strength can also be helpful. Thenar atrophy has a high predictive value in CTS, but is rarely observed

COMPRESSION NEUROPATHY: RISK FACTORS
• hypothyroidism, diabetes, obesity, pregnancy (carpal tunnel syndrome)
• No definitive association with smoking
• Repetitive work questionable, likely more with position and duration of static position • “Double crush”
• Hereditary motor-sensory neuropathies

 Charcot-Marie-Tooth (Hereditary motor and sensory neuropathy – HMSN) – heterogeneous group of neuropathies affecting myelin and the axon

 Hereditary neuropathy with liability to pressure palsies (HNPP) – autosomal dominant demyelinating neuropathy

Question 22

Q

Pathophys of nerve compression?

Question 23

Q

Stages of Nerve compression?

Question 24

Q

Differential for Compression Neuropathy?

Answer

A

Central (ALS) or Proximal compression at cervical spine (radiculopathy) or thoracic outlet syndrome
Peripheral neuropathy/myopathy (B12, folate, alcohol, thiamine, hypothyroid, MS)
Tumours (benign, malignant / primary and metastatic)
Post-traumatic injuries/scarring etc.
Vascular insufficiencies (vasculitis, DM)
Autoimmune/Inflammatory (Guillain Barré, RA, SLE, PAN)
Infection (HIV , Lyme disease, leprosy)
Toxins (gold, arsenic)
Psychological (somatoform and factitious disorders), malingering

Question 25

Q

Question 26

Q

Question 27

Q

What receptors are responsible for sensation?

Answer

A

Slowly adapting receptors (Merkel Cell & Ruffini end-organs) – Tested with Semmes- Weinstein & S2PD
Quickly adapting receptors (Meissner & pacinian corpuscles) – Tested using vibration & M2PDth

Question 28

Q

What parameters are measured with NCS?

EMG?

Answer

A

Tests large myelinated sensory & motor nerves

o Latency (time between stimulus and compound potential)
o Amplitude (may also measure duration and area of sensory or motor action potential); conduction velocity calculated across specific segment
o Conduction Velocity – speed of impulse (uses latency and distance to calculate)

Demyelinating lesion
o stimulation distal to site results in normal amplitude, distal latency and duration of the compound muscle action potential
o stimulation proximal to site conduction velocity decreased by >10 m/s & amplitude by >20%

——

Measures resting electrical activity and voluntary motor unit analysis to assess duration, amplitude, configuration and recruitment

Demyelination – affects recruitment but no abnormal spontaneous activity

Axonal injury – both diminished recruitment and abnormal spontaneous activity;reinnervation leads to new motor unit potentials (MUP)

However, abnormal spontaneous activity not reliably seen until 2 weeks after injury

Fibrillations are seen with denervation (due to increased ACh receptors, can be seen >1-2 weeks post injury and up to 12 months post injury)

Question 29

Q

Median Nerve Anatomy

Question 30

Q

What are the sites of compression in forearm/ Pronator Syndrome?

Answer

A

Supracondylar process humerus – structure present in 1% population
Ligament of Struthers (Supracondylar process to medial epicondyle)
* Symptoms aggravated by 120-135° elbow flexion against resistance
Bicipital Aponeurosis/Lacertus fibrosis (biceps tendon to the fascia of the flexors)
* Symptoms aggravated by 120-135° elbow flexion against resistance, active elbow flexion while in pronation
Between ulnar and humeral heads of pronator teres
* Symptoms aggravated by resistance to pronation of the forearm, combined with wrist flexion (to relax the FDS)
FDS aponeurotic arch – 6.5 cm distal to elbow
* Symptoms aggravated by resisted flexion of the FDS of middle finger

DIAGNOSIS

Altered sensation in radial three and a half digits and palmar cutaneous branch (vs. CTS) o Early sensory disturbance greater on thumb and index (vs. middle finger in CTS) o Symptoms with sustained power gripping or repeated pronation/supination
Pain in the proximal volar forearm (4-5cm below elbow crease), +/- Tinel’s
Rarely is associated with weakness or atrophy of FPL, FDP, (vs. AIN syndrome) or thenar
muscles
Usually not associated with nocturnal paresthesia, rarely bilateral (vs. CTS)

INVESTIGATIONS

NCS/EMG negative in most patients – may help differentiate pronator and AIN syndromes
Possible XR +/- CT/MR depending on clinical situation

TREATMENT

Non-operative:
o Immobilization/splints, anti-inflammatories, corticosteroid injections o Stretching exercises for pronator teres
o Behaviour modification

Operative:

o Failed non-operative >3-6 months
o Approx. 80% patients experience relief
o Curvilinear incision over course of median nerve (ulnar to brachial vessels, parallel to proximal margin of pronator teres) o Work form proximal to distal
 Release ligament of Struthers and any supracondylar bands
 Divide the lacertus fibrosis
 Step-lengthening tenotomy of superficial tendon of pronator teres and excise deep head
 Release the aponeurotic arch of FDS

o Post-operative:

 Splint x 5 days in 45-90o elbow flexion/45o forearm pronation, then begin mobilizing elbow
 If entire pronator muscle detached, then splint forearm in pronation until tendon healed

Question 31

Q

What points on physical would indicate AIN Syndrome?

Compression points

Treatment

Answer

A

PE: Abnormal posture - Hyperextension of DIP and IP

Motor: Unable to OK sign

Weak pronation with elbow flexed

Weak pinch grip

Question 32

Q

Carpal Tunnel NCS Criteria

Answer

A

NCV

o increased latencies (slowing)
o Distal sensory latency >3.2 ms
o Motor latency > 4.3 msec
o Relies only on changes in myelinated fibers (excludes pain & temperature which are often

first to be affected)

Question 33

Q

Conservative Management

Answer

A

Non-operative

Activity modifications/ Posture
PT: Nerve gliding exercises & stretching
Nocturnal wrist splints (neutral position)
+/- steroid injection,
Medical management: NSAIDs, vitamin B6

Question 34

Q

CTR Complications

Diff if no improvement

Answer

A

proximal lesion, peripheral neuropathy, CRPS, malingering, PCB

neuroma)

Depends obviously on diagnosis, but might involve: Re-exploration with extended exposure, +/- neurolysis (external +/- internal) +/- a vascularized flap (eg. PB, PQ, hypothenar fat)

Question 35

Q

Anatomy of Ulnar Nerve

Question 36

Q

Ulnar Nerve Entrapment Points

Diff?

Answer

A

Arcade of Struthers (not Ligament of Struthers) Aponeurosis from medial head triceps to medial intermuscular septeum 8 cm proximal to medial epicondyle. Ulnar nerve travels under it in 70% of people
Medial intermuscular septum (only after anterior transposition)
Medial Epicondyle (wall of cubital tunnel – with elecranon laterally)
Osborne’s Ligament (roof of cubital tunnel)
Anconeus epitrochlearis (accessory muscle)
Medial head of triceps (fascial bands)
Ligament of Spinner (between FCU &FDS D4)
Aponeurosis of FCU (between the two heads)

o Elbow joint pathology: cubitus valgus, osteophytes, ganglia, lipomata, heterotopic ossification
o Subluxation of ulnar nerve across the epicondyle can cause a repeated irritation

DDx: upper motor neuron disease, Guillain-Barre syndrome, cervical disk disease, ALS (motor>sensory complaints & findings)

Question 37

Q

Ulnar Tunnel Sundrome/ Guyon Canal

Differential?

PE?

Answer

A

ETIOLOGY:

Acute or repetitive trauma
Fractures of hamate (hook of hamate non-union), triangular bone, base of 4th of 5th metacarpals
Space-occupying lesions (ganglia > thrombosis or psuedoaneurysms of the ulnar artery)
Anomalous m
uscles

DIAGNOSIS

Motor: Possible weakness of intrinsics. No symptoms in forearm muscles supplied by ulnar nerve

Sensation: Decreased sensation in volar aspect of ulnar one and a half fingers (dorsal sensory branch sparred), Palmar cutaneous branch OK

Special:

Positive Tinel’s at Guyon’s canal

Possible bruits, thrills etc.

NCS/EMG often helpful

X-ray +/- CT/MR (tumours, fractures)

TREATMENT

Non-operative
o Recommended with acute injury in closed trauma (e.g. prolonged cycling)
o Splints wrist in neutral position, NSAIDs, EMG/NCS for monitoring improvement

Operative
o Similar to CTS release but extend proximal and distal, or zig-zag over Guyon’s and extends

proximal to the wrist crease
o Release the volar carpal ligament and pisohamate ligament
o Follow the ulnar nerve into the hypothenar muscles and release any fibrous bands

o Careful to avoid injury to the dorsal branch

Postoperative
o Treat like a carpal tunnel release
o Restricted wrist activity and static splinting with wrist in neutral for 2 weeks at night

Question 38

Q

Describe course of radial nerve?

Question 39

Q

Proximal Radial nerve compression

Answer

A

Operative

o Indication: failure of recovery after 3 months
o Oblique incision from deltoid insertion anteriorly to ulnar elbow
o The nerve is found b/w triceps and brachialis or b/w BR and brachialis
o The lateral intermuscular septum is incised and the nerve traced proximally and distally

Question 40

Q

Anatomy of radial tunnel?

Sites of compression?

Answer

A

Tunnel is 5cm long, defined by
o Laterally – ECRL, ECRB, BR
o Medially – biceps tendon and brachialis
o Posterior – Radiocapitellar joint
o Roof – BR passes over nerve lateral  anterior

May represent an early PIN syndrome

DDX: lateral epicondylitis (may coexist), C6-7 radiculopathy

Potential sites of compression (proximal to distal)

o Fibrous bands radiocapitellar joint (attached to, & superficial to the joint)

o Leash of Henry (radial recurrent artery and venae comitantes)

o Tendinous margin of ECRB
o Arcade of Frohse (most common) – proximal fibrous edge of supinator muscle
o Fascial border at distal edge of supinator

o Others: lateral head of triceps, intermuscular septum, exostoses

Question 41

Q

Diagnosis of Radial Tunnel

Answer

A

—- Diagnosis—

Deep aching in extensor-supinator muscle mass in the proximal forearm

Tenderness +/- Tinel’s 3-5 cm distal to the lateral epicondyle (vs. at the epicondyle in lateral epicondylitis)

No sensory: Usually no distal sensory loss (if SRN are involved, may have altered sensation in dorsal radial hand)

Limited weakness: Usually none or minimal muscle weakness (may have perceived weakness secondary to pain)

Provocative tests (pain with specific maneuver)

o All locations will be aggravated by elbow extension & extension of long finger against resistance

o Fibrous bands at radial neck – Elbow flexion, forearm supination, wrist neutral

o ECRB – Forearm pronation, elbow 45-90 flexion, wrist full extension
o Arcade of Frohse – isometric active supination from fully pronated postion

• EMG/NCS often normal in radial tunnel (abnormal in PIN syndrome)
o PIN carries Group IIa (small myelinated) and IV (unmyelinated) fibers – pressure on these causes pain but they cannot be evaluated by EMG/NCV which shows normal large myelinated fibers)

+/- MR – often negative, may show denervation of muscles, rarely will show a cause of compression

Local anesthetic injections for diagnosis and rule out lateral epicondylitis

Scratch collapse test

Question 42

Q

What is the difference between PIN vs Radial tunnel compression?

Answer

A

Prominent weakness/paralysis PIN innervated muscles & no sensory loss (compared to radial tunnel)

o PIN does not innervate the ECRL – therefore wrist tends to deviate radially during active wrist extension (difficulty with wrist extension in neutral or ulnar deviation)

TREATMENT

• Non-operative
o Rest, activity modification, stretching, splinting, NSAIDS
o Lidocaine/steroid injection at site of compression (3-4 cm distal to lateral epicondyle) o First line for all presentations

• Operative
o Compressive mass on imaging or >3 months failed conservative measures o Anterolateral or posterior approach to elbow (as in radial tunnel)
o Neglected PIN leases to muscle fibrosis requiring tendon transfers

Question 43

Q

Wartenberg Syndrome: Land mark, etiology?

Testing?

Answer

A

Travels deep to BR, emerges between BR and ERCL 9cm proximal to radial styloid Bifurcation proximal to wrist

o Dorsal branch – lies 1-3 radial to Lister’s tubercle (supplies 1st and 2nd websapce)
o Palmar branch – directly over EPL within 2cm of 1st dorsal compartment (supplies dorsolateral thumb)

ETIOLOGY

Iatrogenic or post-traumatic most common

Compression by

o scissoring of BR (superficial) and ECRL (deep to nerve) tendons during forearm pronation

o fascial bands at exit to subcutaneous tissue

History of trauma – forearm fracture, handcuffs, tight wristband/watch/bracelet/case

Other: tumours, hemorrhage, thrombosis of recurrent radial vessels, constrictive jewellery, muscle anomalies etc.

Question 44

Q

Approach to cervical radiculopathy?

Question 45

Q

TOS Classification/ Compression points?

Question 46

Q

TOS

Hisotry and Prov Tests?

Answer

A

Hx: Pain, numbness, tingling, and paresthesia, radicular pain in the arm when elevated or with use

Differentiate from ulnar nerve compression via the involvement of the MABC?

Vascular symptoms: include those of arterial insufficiency as well as edema and DVT’s

Prov: Adson (Scalene), Wright , Halstead (shrug), Roos (overhead), Cervical rotation

Investigations: Neck X-ray, CXR, nerve conduction studies, EMG +/- CT/MR, vascular studies

TREATMENT

o Nonoperative: Physiotherapy is the mainstay of treatment, plus postural correction, weight loss, BBR, muscle relaxants, TENS, ultrasound, heat

o Operative: Surgery associated with high complication rate and is a last resort

 Excision of anterior scalene muscle
 Resection of 1st rib

Question 47

Q

Miagraine Headache:

Etiology? and Trigger Sites?

Answer

A

Caused by vasodilatation of large vessels innervated by trigeminal nerve

o Leads to release of calcitonin gene-related peptide, substanceP, neurokinin A

Hypothesis for migraine surgery/ botulinum toxin used:
o Reducing or eliminating the mechanical stimulation of a possibly sensitized nerve can prevent the onset of pain