Flexor Tendon Injuries Flashcards
What are the origins and insertions of the following flexors:
- FCR
- FCU
- FDS
- FDP
- FPL
FCR
- O: Medial epicondyle
- I: base D2 MC
FCU
- O:Medial epicodyle, ulnar olecranon, proximal 1/3 ulna
- I: pisiform
FDS
- O: 1- Humero-ulno head: Medial epicondyle + Ulnar coronoid. 2- proximal 1/3 radius
- I: MP 2,3,4,5
FDP
- O: ulna proximal 2/3 + IOM
- I: DP 2,3,4,5
FPL
- O: Radius + IOM
- I: DP 1
Where are the Annular pulleys and crucitae pulleys located? And what its the function fo the pulley system?
- A1,3,5 over MCP joints
- A2, 4 over PP and MP
- C1 (b/w A2,3), C2 (b/w A3,4), C3 (b/wA4,5)
Function
- Maximize strength by creating s horter moment arm. With little endone xcursion, we get more ROM
What are the synovial sheaths and 3 functions
Def: fibro-osseous tunnels at the digits and wrist lined with parietal synovial lining
Function
- smooth gliding
- nutrition
- mechanical support to prevent bowstringing
What are the flexor zones
- Distal to FDS insertion
- FDS insertion to distal A1 pulley
- Distal CTR to Proximal A1 pulley
- CT
- Proximal to CT
Thumb
- Distal to IPJ
- A1 to IPJ
- Thenar eminence
What are factors to consider for timing of flexor repair
- Soft tissue coverage
- unstable fractures
- contamination
- shortening of musculotendinous unit
- concomitant injuries
What are contraindications to delayed 1 repair
- inadeqaute ST coverage
- active infection/contamination
What are principles of flexor tendon repair
- Timing
- Best outcomes if 1’ or delayed 1’ (<2wks)
- poor outcomes if >2wk delay (edema.adhesions)
- poor outcomes if >5wk delay (tendon shortening, edema)
- Length
- Tendon graft if >1cm shortened
- Tendon repair
- in zone 2, repair FDP and one slip of FDS (to prevent adhesions, maintain grip strength/prolonged grip strength, prevent swan neck deformity)
- # strands = stregnth of repair
How much of the A2 and A4 can you safely vent
- can cut up to 50% of A2 with no influence on stregnth
- Can vent A4 100% if the pulley system at PIP and DIP is intact
What is the vascular supply to the tendon
- longitudinal vessels perfusing though vincula
- intraosseous vessls
- synovial diffusion
What are tricks for retrieving the proximal stump?
- milking forearm
- skin hook
- proximal icision and feeding it forward
- insert catheter distal to proxima, suture to tendon and pull distally.
- if canal is tight, serially dilate
What are key principles for a technically sound tendon repair
Core suture repair with at least 4 strands (3-0 ticron w 6-0 prolene)
Strickland/indiana (4 strand modified kessler and Horizzontal mattress with epitendinous)
Locking cruciate 4 strand with epitendinous.
If no concerns for catching on pulley, put knot on outside
Place knot in dorsal 1/3 of tendon
What is the puporse of the epitendinous suture?
- increase stregnth of repair by 25-50% (Silverskold increasess strength by 120%)
- decreased gapping
- smooth edges of the repair
What are poor prognostic indications of flexor injury for poor recovery
- associated f#, nerve injury, crush
- delay>3ks in tratment, zone 2
What are startegies to increase the differential glide between tendons
- start ROM protocol at 2-3days post-op (5-7days too late as scar is stronger than tendon)
- need PIP ROM 0-30 for 4mm of tendon glide
- need DIP 0-30 for differential glide
How do you manage tendon repair if no A2 left intact?
use excised slip of FDS for pulley reconstruction and despite pulley recon, can start early AROM
What are methods for 2’ tendon reconstruction
- Tendon grafting (1 stage) indicated if:
- gap >1cm, repair rupture
- pulley system intact or repairable
- Good PROM
- Tendon grafting 2 stages indicated if
- loss of pulley system, digital sheath collapse
- ST disruption/crush injury
- ++scarring
- joint contracture requiring release
- Tendon trasnfer
- proximal muscle not functional
- FDS D4 donor to FPL, FDP of digit to main FDP
- Tenodesis (secure tendon stump down to bone)
- intact FDS and unstable FDP
- Arthrodesis
- irreparable FDP and unstable DIP
What are methods for pulley reconstruction?
- Extensor retinaculum - wrap around flexor and overlap edges volarly secure with stitch then rotate dorsally
- Palmaris longus
- FDS D4
How would you replair partial tendon injuries
- <25% - smooth edges to avoid entrapment
- 25-50% - epitendinous
- >50% core + epitendinous
What are causes of tendon ruptures? attritional (intra-tendon) and treatment?
- RA
- Gout (inflammatory synovitis)
- Hook of Hamate #, DR#
- Iatrogenic - steroid injection
Treatment
- identify and correct underlyign etiology
- tendon graft/ trasnfer
- arthrodesis
What is a mannerfelt lesion
FPL rupture 2’ tendon attrition in RA due to bony spur in CT
How do you classify FDP avulsions and treatment of each
Leddy Packer
- 1- Both vinculae ruptured, retracted into palm
- Repair 7-10days
- 2- Long vinculae intact, retracts to PIP, +/- bony fragment
- Late repair possible
- 3- Fracture-Avulsion with segment held at A4
- ORIF
- 4- F# of DP with avulsion of FDP from bone fragment
- ORIF + tendon reinsertion
Describe the three flexor tendon rehabilitation protocols
* all require DBS
Immobilization
* if young or non-compliant
Dynamic/Early Passive
- Kleinart - dynamic - rubber bands used for active extension, passive flexion
- Duran - Early passive - palmar bar and using other hand, patient move fingers into passive flexion and actively extend
*if stiff edematous fingers=> difficult PROM
Early Active ROM
- Inidiana/synergistic protocol
contraindicated if signiifcant edema and needing self adhesive tape (b/c work of force is 4x greater with edema/tape)
for everyone else who is compliant and does not have a significantly edematous finger
DBS W30ext, MP 40F, IP ext
Describe in Detail the protocol for early passive ROM (Duran or Kleinart)
- Day 3-7 - start protocol
- DBS - wrist 30, MCP 60, IPJ ext
- Wk 1 - 10xq1h active extension, passive flexion in confines of splint. Straps on splint at night
- Wk 4- D/c confines of elastics/palmar bar. Active extension and flexion
- Wk 6 - Active composition extension/flexion, light resistance. Block PIPj. NIght/protective splinting only
- Wk8 - increase resistance, Block DIPj
Describe in detail the protocol for EAM
- Day 3-7 start protocol
- DBS wirst 30, MCP 60 IPJ ext
- Wk1 - 10xq1h active etension, active flexion 1/4 of ROM in confines of splint
- Wk 4 - increase ROM of active flexion and add place and hold
- Wk 6 - Active composite extension, light resistance, block PIP. protective splint at night
- wk 8 - increase resistane, block DIPjt
What is BOyes clasiffication for secondary tendon grafting
- Grade 1- minimal scar, good ROM, no trophic changes = only grade for 1stage tendon graft
- Grade 2- scar, scar contracture of skin
- Grade 3- joint damage - restricted PROM
- Grade 4- nerve damage - trophic changes
- Grade 5 - multi damage
What are complications of flexor tendon repair
EARLY
- hematoma, infection
- rupture
- wound healing
LATE
- adhesions => tenolysis
- rupture =>re-repair
- flexion contracture => extension splinting/capsulotomy
- Swan neck deformity => VP advancement/FDS splinting/transfer/tenodesis
- Quadriga =>tendon lengthening
- Lumbrical plus =>excise lumbrical
What are causes of lumbrical plus deformity (paradoxical IP extension with attempted flexion)
- FDP rupture/severed
- tendon graft to FDP too long
- amputation through middle plhalanx
What are causes of quadrigea?
- on attempted felxion, injured digit reaches palm before rest, leading to felxion contracture of digit and loss of grip strength = decreased excursion
Causes
- tension on repair
- too short of tedon
What are important pediatric considerations fo flexor tendon repair?
- examination may need to be performed intraop
- smaller sutures may be required
- rehab - above elbow cast 4wks then no restriction
Describe a 2 stage tendon repair including indications and steps
INDICATIONS for 2 stage tendon recon
- loss of pulley system/digital sheath
- failed previous repair
- contracted joints requiring release
ADVANTAGE
- places repair outside of zone of injury
- allows interval therapy for joints/soft tissue
STAGE 1
- wide exposure digital sheath w bruner incision
- resect all of FDP excpt distal 1cm and proximal to lumbrical
- distal forearm incision
- excise invovled FDS at MS tendinous jx
- Hunter rod (3-5mm) inserted through intact pulley remanats and sutured to FDP
- recreate pulley at A2/4 w ext retinaculum or excised FDS
- POST-op splint wirst 30, mcp 60 ip 0. Wk 1 PROM, Wk8 full activity
STAGE 2 - 3months later
- harvet stendon graft (plantaris 30cm, palmaris 15cm
- secure graft to proximal rod and pull though
- proximal graft secured w anchor or pull out
- distal graft secured to adjacent FDP
- inset slightly tighter
