L4/5 Hand Trauma Flashcards
Why are Extensor Tendon Injuries often missed?
Skin-cut may not align with the tendon section
Communal extensor bands can compensate
To test extensor function, must stop the others and isolate the finger (ie. Devil’s Horn Sign)
Zones of Extensor Tendon Injuries?
Even numbers over bones
Odd numbers over joints
Management of extensor tendon lacerations?
- Careful inspection of wound (+/- local anaesthesia)
- Zones near joints (odd numbers) must have capsules checked (risk of septic arthritis)
- Repair tendons
- Dynamic extension splinting 4-6 weeks (Rigid splint can cause tendinopathy)
________ test can be used to check the Proximal Interphalangeal Joint Extension.
What is this used to diagnose?
Elson’s Test can be used to check the Proximal Interphalangeal Joint Extension
Useful in diagnosing Boutonniere Deformity (PIP)
25 year old female was playing with nephews when one of them threw a hard ball at her. It struck her right ring finger. A few days later after the swelling had subsided the patient presented to her GP and was quite worried about this deformity.
Name of this deformity and test to check it?
ELSON’s Test used to diagnose Boutonniere Deformity (Proximal Interphalangeal Joint):
Need to check if the Lateral bands are still active and able to extend the finger. When opposition is applied to the finger, bend tip of the finger:
- if supple, then central slip still intact
- if unable to bend the tip of finger => reliant on lateral slips as central torn
Name of injury to Distal Phalangeal Joint?
Mallet finger (DIP)
Injury resulting in failure to flex distal phalanx?
Injury to ulnar collateral ligament of the metacarpal pharyngeal joint?
Gamekeeper’s thumb = Skier’s thumb
A two-piece fracture dislocation of the base of the thumb metacarpal?
Bennett’s Fracture
Down at base of first metacarpal
Skiier’s thumb more distal
Comminuted fracture (>2) dislocation of the base of the thumb metacarpal?
Rolando Fracture: comminuted Bennett’s (worse prognosis)
Non displaced stable fractures can be treated with ____________
Non displaced stable fractures can be treated with buddy tape
________________fractures need open reduction and fixation w/ K Wires
Angulated Condylar fractures need open reduction and fixation w/ K Wires
What type of fracture is this?
How to Treat?
Boxer’s Fracture
To heal boxers buddy strap 4/5 and bend at 90* to give collateral ligament tension
Pathogenesis of Fight Bites?
What to be wary of?
Polymicrobial: 3/5 anaerobes
- Strep
- Staph aureus
- Eikenella corrodens (gram-negative rod) (30% of infections)
Does it involve synovial sheets w/the potential to spread to other flexors/extensors
Nerve blocks of hand?
Where do digital nerves travel?
Test for functional Anterior Interosseous branch of the Median nerve?
All hand muscles are innervated by Ulnar nerve EXCEPT (5)
Lumbrical 1/Lumbrical 2
Thenar Muscles
- Flexor Pollicis Brevis (superficial head)
- Abductor Pollicis Brevis
- Opponens Pollicis
Cause of Ape Hand and Thenar Atrophy?
As Thenar muscles are Innervated by the recurrent branch of median nerve, problems with this nerve can lead to Thenar Atrophy
Median nerve damage=> Thenar atrophy=> Ape Hand = >Difficult for individual to Abduct thumb
What supplies all muscles of the hand except for 5?
Deep Motor Branch of Ulnar Nerve
___________ limit hyperextension of MCP joints
Lumbrical muscles limit hyperextension of MCP joints
Sign of Ulnar Nerve injury?
Lumbrical muscles limit hyperextension of MCP joints
Lumbricals 3/4 are supplied by ulnar (weak) => Hyperextension at rest
Sign of Median Nerve Injury?
What does Froment’s Sign test for?
Adductor pollicis innervated by Ulnar Nerve
Froment’s Sign (pulling paper from between pinched fingers) is indicative of Ulnar Nerve Palsy
Conditions that present with “Claw-like hands” that are not ulnar injuries?
Dupuytren’s Contracture
- Over-proliferating fibroblasts => thickening of palmar aponeurosis
- Metacarpal pahregeal joint is NOT hyperextended (can’t be ulnar problem)
Volkmann’s Contracture
- Damage to vasculature => ischemic damage to muscles=> Wrist and Digits Flexed
- Metacarpal pahregeal joint is NOT hyperextended (can’t be ulnar problem)
What is the Ulnar paradox?
“The closer to the paw the worse the claw”
In a high ulnar lesion (Elbow) the clawing is paradoxically milder than in a low lesion. This is because in the low lesion (Wrist) the hand muscles are weak but the long flexors which are supplied by the ulnar nerve just below the elbow are not affected. In the high lesion both are weak and the clawing is milder.
Hard vs. Soft Signs of Vascular Injury in Orthopedic Trauma?
Hard Sign (More Specific Indicator of Condition)
- Pulselessness
- Pallor
- Paresthesia
- Pain (Uncontrollable)
- Paralysis
- Rapidly Expanding Hematoma
- Palpable Thrill or Audible Bruit
Soft Sign: Less specific/diagnostic of injury
- History of bleeding
- Proximity-related injury
- Neurologic finging from nerve adjacent to artery
- Hematoma over artery
What test assesses profusion of the hand?
What is this used for?
Allen’s Test: test for profusion of hand
shows dominance of ulnar or radial artery issue with one or the other
Where does the innervation of the thenar muscles occur?
Kaplan’s Cardinal Line
Recurrent (Motor) brnach of median nerve enters the thenar muscle mass at this point
Normal Capillary Refill time?
Measurement of blood flow in hand arteries?
Technique for Artery ligation?
Stick Tie: Suture through the wall of artery
Treatment of Nail bed Injuries?
If <50% of nail area: drain by perforation (sterile needle or hot paper clip)
Nail bed repair
- Remove nail (soak in Betadine)
- Suture nail bed with 6-0 suture OR2-octylcyanoacrylate (superglue)
- Splint the eponychial fold with original nail
- Non adherent gauze
Loss of germinal matrix requires graft: must be in tact for growth of new nail
Name/Treatment of this?
Regrowth of Nails?
Germinal Matrix must be intact for growth of new nail
The ring finger (fourth digit)
A. Has 2 proper digital nerves, continuations of the ulnar nerve
B. Would have loss of sensation to the nail bed with
injury to the superficial branch of the radial nerve
C. May have altered sensation following a focal sharp piercing of carpal tunnel
D. Is supplied by the deep ulnar nerve over the medial half of the finger
E. Has mixed C7-C8 dermatomal supply
A girl playing softball cuts the palm of her hand as she scoops up a piece of glass along with the ball. If the only nerve damaged is the recurrent branch of the median nerve, she would lose what movement of the thumb?
Opposition!! This would result in thenar nerve damage!
