Hand Flashcards
1
Q
Swan neck deformity
Classification (Nalebuff) and Treatment: Type Description PIPJ flexion limited in certain positions Treatment options
- I PIPJ completely flexible
- Splinting with double ring splints DIPJ fusion
- if mallet deformity significant Consider spiral oblique retinacular ligament reconstruction (SORL)
- II (tight intrinsics) reconstruction
- Lateral band translocation (Littler)
- Intrinsic release if necessary +/- MCPJ
- III PIPJ flexion limited in all positions
- Dorsal release FDS tenodesis or lateral band translocation
- IV PIPJ stiff with radiographic changes
- Arthrodesis – consider for index and middle fingers if stablitiy is important Arthroplasty
A
Hyperextension at the PIPJ - Flexion of the DIPJ
- Pathoanatomy:
- primary lesions is a lax volar plate, allowing producing hyperextension at the PIPJ from -
- Trauma
- Rheumatoid arthritis
- Generalised joint laxity
- Secondary lesions arise from an imbalance of forces at the PIPJ,( (PIP extension forces that is greater than the PIP flexion force).
- mallet injury
- leads to transfer of DIP extension force into PIP extension forces
- FDS rupture
- leads to unopposed PIP extension combined with loss of integrity of the volar plate
- intrinsic contracture
- tethering of the lateral (collateral) bands by the transverse retinacular ligament as a result of PIP hyperextension
- if the lateral (collateral) bands are tethered, excursion is restricted and the extension force is not transmitted to the terminal tendon, and is instead transmitted to the PIP joint
- MCP joint volar subluxation
- caused by rheumatoid arthritis
2
Q
Ulnar claw -
- Aim to prevent hyper-extension at the MCPJs, thus allowing the extrinsic extensors to extend DIPJs and PIPJs -
- One of the methods of bringing the MCPJ into flexion is by passing the FDS volar to the A1 pulley and suturing it back on itself (Zancolli Lasso proceure) -
- MCPJ capsulodesis
A
Ulnar nerve palsy -
- Thumb adduction: split insertion of middle finger FDS/BR to adductor pollicis brevis
- Index abduction: EIP or AbPL to first dorsal interosseus
- Wartenberg deformity: EIP to EDM
- High ulnar lesion (loss of FCU and FDP) - Suture FDPs to functioning index and middle FDP -
- In addition, transfers for low lesion
3
Q
Radial nerve palsy -
- Wrist extension: pronator teres to ECRB/ERCL -
- Finger extension: FCR or FCU to EDC -
- Thumb extension: Palmaris longus to EPL
A
Median nerve palsy Low lesion: -
- Aim to regain opposition (loss of APB)-FDS ring/Abductor digiti minimi/PL to AbPB
- High lesion: -
- Thumb IP flexion (loss of FPL) – BR to FPL -
- Index and middle flexion – side to side tenodesis of FDP to functioning FDP ring and little -
- In addition, transfers for low lesion
4
Q
Boutonniere Deformity
A
- A Zone III extensor tendon injury characterized by PIP flexion DIP extension
- Mechanism -
- caused by rupture of the central slip over PIP joint from laceration
- traumatic avulsion (jammed finger)
- capsular distension in rheumatoid arthritis
- Pathoanatomy -
- pathoanatomic sequence includes rupture of central slip causes the extrinsic extension mechanism from the EDC to be lost prevents extension at the PIP joint
- attenuation of triangular ligament causes intrinsic muscles of the hand (lumbricals) to act as flexors at the PIP joint
- lumbricals also extend the DIP joint without an opposing or balancing force palmar migration of collateral bands and lateral bands the lumbricals’ pull becomes unopposed, pulling through the base of the distal phalanx and volar to the PIP causes PIP flexion and DIP extension bone deformity injury involves all three phalanges the middle phalanx flexes on the proximal phalanx at the PIP joint the distal phalanx is hyperextended relative to the middle phalanx at the DIP joint Associated conditions rheumatoid arthritis pseudo-boutonniere – refers to PIP joint flexion contracture in the absence of DIP extension
5
Q
Swan Neck Deformity Causes
A
- Characterized by - hyperextension of PIP, flexion of DIP
- Caused by lax volar plate imbalance of muscle forces on PIP (extension force > flexion force)
- Injuries include
- MCP joint volar subluxation (rheumatoid arthritis)
- mallet finger
- FDS laceration
- intrinsic contracture
- Seen in rheumatoid arthritis
- Primary lesion is lax volar plate that allows hyperextension of PIP.
- Causes include
- trauma
- generalized ligament laxity
- rheumatoid arthritis
- Secondary lesion is imbalance of forces on the PIP joint (PIP extension forces that is greater than the PIP flexion force).
- Causes of this include mallet injury leads to transfer of DIP extension force into PIP extension forces
- FDS rupture leads to unopposed PIP extension combined with loss of integrity of the volar plate
-
intrinsic contracture -
- tethering of the lateral (collateral) bands by the transverse retinacular ligament as a result of PIP hyperextension
- If the lateral (collateral) bands are tethered, excursion is restricted and the extension force is not transmitted to the terminal tendon, and is instead transmitted to the PIP joint
- MCP joint volar subluxation caused by rheumatoid arthritis
6
Q
Seymour Fracture
A
- Displaced distal phalangeal physeal fracture with an associated nailbed injury body
- location - middle finger injury is most common type of the distal phalangeal physeal fracture:
- metaphyseal fractures 1 to 2 mm distal to the epiphyseal plate
- Salter-Harris II fractures
- Type of nailbed injury:
- nailbed laceration
- nail plate subluxation
- interposition of soft tissue at fracture site (usually germinal matrix)
-
Pathoanatomy
- Similar mechanism to mallet finger in adults injury
- causes flexed posturing of the distal phalanx deformity
- results from an imbalance between the flexor and the extensor tendons at the level of the fracture
- Imbalance occurs due to different insertion sites of flexor and extensor tendons
- extensor tendon inserts into the epiphysis of the distal phalanx flexor tendon inserts into metaphysis of the distal phalanx widened physis likely to have interposed tissue in the fracture site
7
Q
Ulnar drift at MCP joint
A
pathoanatomy
joint synovitits
- radial hood sagittal fiber stretching >
concomitant volar plate stretching
- extrinsic extensor tendons subluxate ulnarly >
- lax collateral ligaments allow ulnar deviation deformity >
- ulnar intrinsics contract further worsening the deformity >
- wrist radial deviation further worsens >
- flexor tendon eventually drifts ulnar
https://www.orthobullets.com/basic-science/9085/rheumatoid-arthritis
https://www.clinicalkey.com/#!/content/book/3-s2.0-B9780323672177000730?scrollTo=%23hl0001408
8
Q
Differentials for loss of digital extension
A
- PIN neuropathy
- extensor tendon rupture
- extensor tendon subluxation (torn radial sagittal band)
- MCP volar subluxation
- trigger finger
9
Q
Dupuytren’s Disease
A
- Pits & Nodules
- Cords (Pretendinous, Natatory,
- Lateral, Spiral, abductor digiti
- minimi, commissural)
- Scars
- Dermofasciectomy
- Garrods pads
- Feel the cords/nodules
- Measure joint contracture
- Table top test
- NV, digital Allen’s test
10
Q
Ulnar Nerve Injury
A
- Skin changes: ulcers, nails,
- swelling & inflammation
- Wasting: ulnar side of forearm, hypothenar & 1st
dorsal interosseous
- Deformities: Cubitus Valgus, clawing & Wartenberg’s
- -Scars: medial condyle, forearm, volar aspect of wrist
- Sensation @ tip of little finge & dorsum of 5th MC
- Tenderness: Cubital tunnel (Vs medial epicondyle),
- Ulnar nerve instability
-
Muscle Power:
- FCU
- Little finger FDP -Pollock test
- Intrinsics – Froment’s test
- Star sign (little and index finger abduction)
- Card test (finger adduction- PAD)
- Cross fingers (DAB)
- Tinel’s (Cubital & Guyon’s tunnels)
- Elbow hyperflexion
11
Q
Radial N injury
A
- Skin changes: ulcers, nails, swelling & inflammation
- Wasting: Radial side of proximal forearm
- Deformities: Dropped wrist splints
- Scars: Over triceps & Henry’s
- Sensation: Dorsum of 1st web space (Superficial Radial)
- Tenderness: Distal to lateral Epicondyle (Vs Tennis elbow)
-
Power:
- Main: Triceps, BR & ECRL o PIN: ECU, EI, EDM, EPL
- Resisted supination with extended elbow (Frohse)
- Wrist extends W/ rad deviat
12
Q
Median Nerve
A
- Skin changes: ulcers, nails, swelling & inflammation
- Wasting: Thenar, APB
- Deformities: Wrist fracture, benediction, Simian thumb
- Scars: CTD, Proximal Forearm (pronator Syn Release)
- Sensation: Tip of Middle F & Thenar eminence
- Tenderness: Proximal radial forearm (Pron Syn), Tinel over Carpal T
- Power
- Forearm: FCR & FDS o Intrinsic: APB & OP
- OK sign: FPL + Index FDP (AIN)
13
Q
- Dupuytren Contracture
A
Dupuytren disease is a proliferative fibroplasia of the subcutaneous palmar tissue occurring in the form of nodules and cords that may result in secondary progressive and irreversible finger joint flexion contractures
Normal fascial bands become pathologic cords
- Palmar
- pretindinous cord
- Palmodigital transition
- natatory cord
- spiral cord
- pretendinous band
- spiral band
- lateral digital sheet
- Grayson’s ligament
- Digital
- central cord - distal extent of the pretendinous cord
- lateral cord
- digital cord
- retrovascular cord
14
Q
Swan neck deformity Classification
A
- Type I deformities are flexible and require dermodesis, flexor tenodesis of the proximal interphalangeal joint, fusion of the distal interphalangeal joint, and reconstruction of the retinacular ligament.
- Type II deformities are caused by intrinsic muscle tightness and require intrinsic release in addition to one or more of the aforementioned procedures.
- Type III deformities are stiff and do not allow satisfactory flexion but do not have significant joint destruction radiographically. These deformities require joint manipulation, mobilization of the lateral bands, and dorsal skin release.
- Type IV deformities have radiographic evidence of destruction of the joint surface and stiff proximal interphalangeal joints, which usually can be best treated with arthrodesis of the proximal interphalangeal joint or, in the ring and small fingers, possibly proximal interphalangeal joint arthroplasty if the metacarpophalangeal joints are well preserved.
15
Q
Nerve conduction study
A
