Wrist And Hand Flashcards
Wrist bones
SLTPTTCH
Scaphoid, lunate, triquetrum, pisoform
Trapezium, trapezoid, capitate, hamate
Scaphoid problem
Has a high incidence of non-union
Lunate Problem
Most common carpal bone dislocated (not verified, heard this in PPT)
When to refer for imaging of wrist?
- Scaphoid TTP
- Traumatic history
- Not willing to move
- Exquisite pain on palpation
Types of wrist fractures?
Colles = complete fracture of radius (close to the wrist) with dorsal displacement (and possibly radial; displacing radioulnar joint) of distal fragment
Smith = fracture of radius (usually from hyper flexion) and the distal fragment goes towards the palmar side of hand
Barton = fracture of distal radius with dislocation of radiocarpal joint (fracture can be palmar or dorsal direction)
Types of Hand Fractures?
Boxer’s = break in neck of 5th metacarpal
Bennett’s = fracture plus dislocation of 1st metacarpal bone at base of thumb
Scaphoid fracture
Hook of hamate fracture
Types of AVN in the wrist
Kienbock’s Disease = AVN of lunate
Preiser’s Disease = AVN of scaphoid
AVN of triquetrum
Wartenberg’s Disease
Superficial radial nerve entrapment between brachioradialis and ECRL. Only sensory and gives pain over distal radial forearm and paresthesias of dorsal radial hand. Often confused with DeQueirvain’s.
Peripheral nerve distribution pattern
Superficial branch radial nerve = radial thumb and dorsal 1-4 (1/2 of 4) but not the tips
Median nerve = palmar digits 1-4 (1/2 of 4) and dorsal tips
Ulnar nerve = ulnar hand and pinky plus 1/2 of ring
Claw Hand
Claw Hand: Ulnar nerve palsy at cubital tunnel that causes MCP extension, IP flexion (due to weakness of intrinsics) at digits 4 and 5.
Since the lesion is at wrist, ulnar portion of FDP is spared. The EDC is good at extending MCP’s but can’t extend IP’s due to lack of assistance from interossei through dorsal hood).
What does ulnar nerve innervation in the hand/forearm?
- Lumbricals 3 and 4
- All interosseous muscles
- Add Pollicis
- Deep head of flexor pollicis brevis
- All hypothenar muscles
- FCU
- Medial 1/2 of FDP
What muscles help extend the fingers?
The EDC isn’t strong enough to extend the IP joints, only MCP joints. The lumbricals and interossei attach onto the posterolateral aspect of the extensor hood (expansions of EDC) to help extend IP joints.
What does median nerve innervate
- FDS
- Radial FDP
- Thenar muscles
- Pronator quadratus
- Lumbricals of middle and index finger
- FPL
- FPB
Ape Hand
Median nerve injury. The thenar muscles are paralyzed and now the adductor pollocis is unopposed and pulls thumb up into plane of other fingers.
Sign of benediction
Seen with high median nerve injury and is an active sign. When person tries to make a fist they can only engage the ulnar side of the FDP that innervates the ulnar 2 fingers.
Radial Hand Common Conditions
- CMC OA
- Scaphoid or radius Fx / AVN
- DeQuervain’s
- Skier’s Thumb
Scaphoid fracture
- Usually a FOOSH
- Radial wrist pain that is worse with loading
- Positive scaphoid compression test (axial load through 1st MCP or radial deviation and axial load through 2nd/3rd MCP)
- May not have positive imaging finding immediately (be concerned about Preiser’s Disease - AVN of this)
De Quervain’s
1. Tendons affected
2. Splinting time
1.Most common in EPB, APL.
2. If indicated, 4-6 weeks
Most important wrist ligaments?
In proximal row: scapholunate and lunotriquetral (link lunate to adjacent bones).
Articular Disc of wrist
Originates from ulnar EDGE of distal radius and covers the ulna. Blends with radioulnar ligaments.
TFCC components and function
- TFC Disc (lies on distal ulna)
- Meniscus homologous (between ulnar styloid and triquetrum)
- Radioulnar ligaments
- ECU sheath
- UCL
- Ulnolunate and ulnotriquetral ligaments
Stabilizes DRUJ, ulnar carpal bones, transmits load between ulna and lunate/triquetrum.
Blood supply to hand
Superficial arch from ulnar artery, deep arch through radial artery.
Tendons through carpal tunnel
- Finger flexors
- FPL
Guyon’s Canal
Contains ulnar nerve and artery and passes between pisiform and hook of hamate.
What are the borders of the snuffbox?
From Left to Right
APL -> EPB -> EPL
Test motor function of median, ulnar, radial nerves?
Median: Thumb abduction against resistance
Ulnar: Index abduction
Radial: Pull thumb dorsally against resistance
Gilula’s Lines
Smooth continuous arcs representing the proximal and distal carpal rows. If disrupted, disorder may be present.
How long do wrist fractures USUALLY take to heal?
6-8 weeks
Most common carpal fractures
- Scaphoid
- Dorsal cortical triquetral
How to diagnose scaphoid fracture?
- Radial sided wrist pain
- TTP anatomic snuffbox
- Pain with axial loading of thumb
- MRI needed if x-ray needed and high suspicion detected
Problems with scaphoid fractures?
The blood supply enters from distal half, as a result, proximal fractures are at high risk for development of AVN and non-union
Managing scaphoid fractures?
Non-displaced can be in thumb-spica cast immobilization or compression screw fixation. Screw fixation allows for immediate gentle AROM and progressive strengthening at 2 weeks. Displaced fractures need surgery. Proximal 1/3 fractures may be at higher risk for nonunion for those who return to play in cast or splint.
How to find hook of hamate?
1 thumbnail radial and distal to the pisiform
Scapholunate ligament tear
- Usually fall on extended/ulnarly deviated wrist
- TTP 1 cm distal to lister’s tubercle (dorsal ridge in center radius)
- Positive Watson shift test
Watson Shift Test
Apply a dorsal force to the scaphoid. Start with hand in ulnar deviation and slight extension then maintain the scaphoid pressure as you bring the wrist into radial deviation/flexion. The scaphoid will want to come forward and if scapholunate dissociation will hear/feel thunk/clunk when letting go of this dorsal pressure.
Perilunate dislocation
Results from disruption of scapholunate ligament and then extension of the injury through Capito-lunate articulation and lunotriquetral ligament. Can also occur through fracture dislocation through scaphoid. Could lead to deformation of carpal tunnel (paresthesias or numbness in median nerve distribution). Needs reduction immediately.
Management of TFCC tears
Non-Op: Splinting, NSAID’s, steroid injection
Operative: Debridement in central, avascular portion (usually can play in a few weeks). Often repair in peripheral portion.
ECU Subluxation
Exam may show this with circumduction of wrist. May not be able to elicit during exam though. May be TTP in ulnar fovea. Can be splinted in neutral or may need reconstruction of tendon sheath.
Intersection syndrome
Intersection of APL/EPB and ECRL/ECRB. Needs to be differentiated from Wartenberg’s and DeQuerain’s. May have swelling at the intersection.
Skier’s Thumb
+ UCL stress test (on web space side). Pain with gripping and palpation.
Ulnar wrist pain
- TFCC
- Wrist/Hand OA
- Carpal instability
- Ganglion cyst
- Kienbock’s (AVN of lunate)
Presentation of TFCC tear
- Usually FOOSH, rotation, or axial loading
- Pain along ulnar wrist
- Ulnar fovea sign
- Positive TFCC load test
- Piano keys test
- Limited wrist ext > flex
- Pain with resisted pronation
TFCC Special Tests
- TFCC Load Test: Grasp distal forearm. Grab at MC’s and then ulnarly deviate and load (click or pain)
- Piano Keys Test: Palm resting down on table. Stabilize the radius and wrist. Press down on the distal ulna and see if painful (TFCC) or increased ROM (distal radioulnar instability)
- Press test: grab arm rest and get up from chair
Diagnosing ganglion cyst?
Usually see a bump. Diagnose with palpation or imaging.
Lunotriquetral Instability Special Tests?
- Reagan’s test: Stabilize the triquetrum as you mobilize the lunate palmarly looking for pain and instability.
- Shuck test: like the Reagan’s test but you just mobilize the lunate and triquetrum in opposite directions.
- Murphy’s sign: Have patient make a fist. Look to see the position of the middle finger knuckle, it should usually be farther than the ones next to it. If it’s equal with the others it may be because it sunk back and is now even with the others because of the dislocation.
Mallet Finger
Injury to the extensor tendon at the DIP joint. A ball strikes the extended finger. Extensor tendon is torn or avulsed. Patients won’t be able to extend DIP.
If no avulsion fracture should be splinted in neutral or slight hyperextension for 6 weeks, PIP should remain free. If they flex the digit the splinting time must restart. They can continue to play sports while splinted. If after 6 weeks they have active extension they can no only wear the splint for 6 weeks during sleep and sports.
Swan Neck and Boutonnière Deformity?
Swan: PIP hyperextended (volar plate tear)
Boutonnière: PIP flexed, MCP/DIP extended (rupture of central tendon slip of extensor hood)
Dupuytren’s Contracture
Inability to extend 4th and or 5th digits. MCP/PIP’s flexed. May have lump in the palm of the hand.
Volar Plate and palmar/frontal stability.
Multiple layers of fibrocartilage between the flexor tendons and palmar PIPJ capsule. There are collateral ligaments and check-rein ligaments as well.
Jersey Finger
Disruption of FDP (forceful grabbing of jersey). Ring finger is 75% of cases. The finger is extended at rest and can’t flex DIP. Test by isolating DIP flexion.
Central Slip Injury
PIP is forcibly flexed while actively extended. Volar dislocation of PIP can also cause central slip ruptures. To examine, hold joint in 15-30 flexion and ask them to extend it. Can cause boutonnière deformity and lateral bands of EDC migrate volarly. PIP should be splinted in full extension for 6 weeks and if able to actively extend 6 more weeks with only sports/sleep.
Collateral Finger Injury
Caused by forced ulnar/radial force. PIP usually involved and classified as “jammed finger”. Pain to palpation in affected ligament. To examine, place MCP in 90 flexion (this slackens collateral ligaments) and involved joint at 30 flexion, then do varus/valgus stress. Can be treated with buddy taping above and below joint. If ring finger involved it should be secured to 5th digit because the 5th digit is naturally extended and easily injured if exposed. Often refer children with this because growth plate is often involved.
Volar Plate Injury
Hyperextension, such as a dorsal dislocation can injure volar plate. PIP usually affected and collateral ligament damage often present. May lead to swan neck. Stable joint should be splinted with progressive extension splint (starting at 30 degrees flex for and progressing in extension weekly up to 2-4 weeks).
Most common finger dislocations? What direction does it occur?
PIP. Direction is usually dorsal, lateral and volar can occur.
Injuries associated with PIP dislocation?
Injury to volar plate with dorsal dislocation.
Management of dislocated finger on field?
For PIP, DIP, or MCP. MD can attempt to reduce this without radiography. If successful, buddy tape in slight flexion for dorsal and extension for volar and can return to participate in athletic even. Should get radiographs after and for dorsal should be splinted in 30 degrees flexion after for 2-4 weeks, followed by buddy taping. For volar should be splinted in extension for 6 weeks.
Detecting phalanx fracture with rotation
Subtle rotation can be detected by having patient make fist or semiflexed fingers, all fingernails should point towards scaphoid.
Boxer’s Fracture
Fracture at neck of 5th metacarpal.
What metacarpals are most commonly fractured?
They increase in incidence from the radial to ulnar side.
Scaphoid Fracture Incidence in Different Ages
Rare in young children and elderly, it is much stronger than the radius.
What movements does the scaphoid limit?
In limits extension and radial deviation because it conflicts with radius.
Scaphoid and AVN
No blood vessels enter the proximal pole so a fracture at the waist (between distal and proximal poles) can leave proximal pole at risk for AVN.
Imaging with suspected scaphoid fractures?
If x-rays negative should repeat in 7-14 days and if negative again but pain persists, need CT or MRI. If no fracture they should be pain-free by 2 weeks.
Management of scaphoid fractures?
6 weeks of immobilization with repeat images if in distal pole and not displaced. Time to heal increases as the fracture is more proximal.
Healing Time/Casting For Radius Fracture?
Non displaced is casted for 6-8 weeks and then protective splint for 3 weeks.
ROM following open reduction of radius?
Active ROM can begin within 3-5 days after ORIF.
At 2 weeks (accelerated) and 6 weeks (standard) the patient can advance AROM to progressive stretching and passive ROM.
At 6-8 weeks wrist motion should be close to normal and strength exercises can begin if fracture is healed.
Can return to all previous activities at 3 months except contact sports by 6 months.
Where is radius weakest?
At the distal metaphysis of radius the cortex of bone is thinner than proximal/distal to this and distal do the relative amount of cancellous bone increases.
Other areas sometimes injured with colles fracture?
Ulnar styloid fracture, TFCC tear (can happen often), scapholunate dissociation.
How are TFCC grip/wrist strengthening exercises progressed?
Started in position of supination, progressing to neutral and then pronation.
Post-Surgical Rehab For TFCC Debridgement
- ROM for first 2 weeks
- Stretching/functional activities introduced in no adverse response
- Strengthening at week 4
- Return to play at 3 months
Post-surgical rehab after TFCC repair
- Immobilization for 3-6 weeks
- ROM in flex/ext first and progressed to ulnar deviation and rotation
- Impact loading and sport participation avoided until 12 weeks
With scapholunate dissociation, how will scaphoid and lunate be positioned?
Scaphoid = palmar flexion
Lunate = dorsally
Scapholunate instability:
1. Where is pain
2. Symptoms
- Dorsal/radial
- Pain with push up, clicking/catching, feelings of instability/weakness
Special Test for Boutonnière deformity?
Elson test: bend PIP 90 degrees over edge of table and try to extend the MIDDLE phalanx. If weak and the DIP gets rigid this is a positive test (DIP should stay limp)
Trigger Finger
Inhibition of smooth tendon gliding at level of A1 pulley (at MCP joint). May have thickening here. May get splinting, anti-inflammatories, steroid injections, or surgical release. Most common in ring/middle finger. Usually affects FDP tendon only.
