extensor tendons injury and deformity

extensor tendons injury and deformity

1. Extensor tendon injury
& associated deformities
Dr Sumer Yadav
Mch – Plastic and Reconstructive surgery
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2. ANATOMY OF EXTENSOR
FORE ARM
Proximal group: The
ECU,EDM,EDC,ECRL,ECRB tendons
originate adjacent to the lateral epicondyle of
the humerus and are innervated proximally
Distal group: The EPL,EIP,AbPL & EPB
originate in the distal half of the forearm.
There fore, a proximal laceration with loss of
function in distal group probably represents a
motor nerve injury.
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6. Muscles of the Forearm lateral
(Extensor Surface)
Outcropping Group
Extensor Pollicis Brevis/
Abductor Pollicis Longus
Extensor pollicis longus
Medial Group
Extensor Carpi radialis
L/B
Bracioradialis
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7. ARRANGEMENT OF
EXTENSOR TENDONS AT
WRIST
The Extensor tendons gain entrance to hand
from the fore arm through a series of six
canals, 5 fibro-osseus & 1 fibrous( the 5
th

dorsal compartment containing EDM)
The Communis tendons are joint distally near
the MP joint by fibrous inter connections
called Junturae Tendinum
The Proprius tendons( EIP&EDM) are
independent finger extensors and they lie on
the ulnar side of the their respective EDC
tendons
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11. EXTENSOR MECHANISM IN
FINGER
At the MP joint, the Extensor mechanism flattens into a broad
hood and envelops the dorsal third of proximal & middle
phalanges
Fibers of the common extensor tendon blend with the fibers of
lateral bands to form the central slip which inserts in the base of
the middle phalanx & effects PIP joint extension
The central slip is kept in its dorsal position by the Transverse
Retinacular ligament
The lateral bands are held dorsal to the axis of the PIP joint by
fibers of the Triangular ligament
SORL originates on the palmer plate & flexion sheath beneath
the PIP joint .These fibers move dorsally to insert in the terminal
tendon. With PIP extension , fibers of the SORL tighten to assist
DIP extension
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15. MECHANICS OF HAND
Two set of muscles, INTRINSIC (originating in the hand itself &
innervated by the Ulnar and Medial nerves) and EXTRINSIC
(originating in the forearm & innervated by the Radial nerve) act
synergistically
The extensor system prepares the hand for grasp & pinch by
positioning the hand in various degrees of extension.
The most frequent activities of daily living occur in positions
close to the position of function like holding a cup or writing with
a pen. More specialized activities like grasping a large or a very
small object occur at the extremes of extension & flexion
An Extensor tendon laceration results in the decrease in the
extensor force distal to the injury. This force is then transferred
to the joint proximal to the injury, resulting in a net increase of
extensor force at that joint, which causes a change in that joint
position leading to characteristic deformities
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16. FULL FLEXION EXTENSION
ARC
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18. TENODESIS EFFECT
Dynamic Tenodesis is defined as the concept
of movement at one joint transmitting power to
an adjacent joint( usually distal)
As the wrist flexes , the extensor tendons
tighten and the flexor tendons relax, both
actions serving to produce extension of the MP
joints. The intrinsic tendons tighten with MP
extension, augmenting PIP extension
The lateral bands & the ORL are lax with PIP
flexion and tighten with PIP extension. The
Tenodesis effect of the ORL can be
demonstrated by checking passive flexion of
the DIP joint with the PIP joint in flexion and
extension
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19. ZONES OF INJURY
ZONE FINGER
THUMB
I DIP joint IP joint
II Middle Phalanx Proximal Phalanx
III PIP joint MCP joint
IV Proximal Phalanx Metacarpal
V MCP joint Carpometacarpal joint/
Radial Styloid
VI Metacarpal
VII Dorsal Retinaculam
VIII Distal forearm
IX Mid & Proximal forearm
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20. Each zone in the fingers refers to an identical
location. The thumb lacks a middle phalanx.
Consequently the thumb zones I to V refer to
different anatomic location relative to the
fingers
 60% of Tendon injuries occur in zone V to
VIII ( MP joint to distal fore arm)
Outcome is more favorable in zone V to VIII
injury as compared to zone I to IV injury
More than 50% of injuries have an associated
injury such as fracture, dislocation or flexor
tendon injury

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22. CLINICAL EVALUATION
Testing for EDC, EIP & EDM
musculotendinous function
The proprius tendon to the index &
little finger are capable of
independent extension.
Their function together can be
evaluated with the middle & ring
finger flexed into the palm , the
proprius tendons can extend the ring
& little finger
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23. TESTING PROPRIUS
TENDONS
With the middle & ring fingers flexed into
the palm, the Proprius tendon can
extend the index and little fingers
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24. EPB tendon can be checked by
placing a finger in the anatomical
snuff box and asking the patient to
extend the thumb in a flat position
APL tendon can be checked by
asking the patient to abduct the
thumb against resistance
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25. Evaluation of wrist extensors
& deviators
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26. Testing the EPL tendon
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27. ZONE I INJURY
Occurs at the DIP joint of the finger or
the IP joint of the thumb
Mechanism of injury is usually forced
flexion of an actively extended distal
joint
aka Mallet finger, Base ball finger,
Dropped finger, or Extension lag

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28. MALLET FINGER
Mechanism : a blow from a thrown ball
strikes the tip of the finger--- ‘forced flexion’.
It tears the extensor tendon from its insertion
+/- dorsal tip of distal phalanx
Clinically , there is extensor lag with localized
DIP joint tenderness . The athlete is unable to
extend the DIP
Investigation : radiographs to rule out
fracture with volar subluxation
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31. MALLET FINGER
Management : continuous splint immobilization for 4 to 6
weeks in full extension
Indications for surgery: open injuries, closed injuries in a
person who will be unable to work with a splint on e.g. health
care worker and a large dorsal fragment with palmar
subluxation of the distal fragment
Complications : skin ulceration is most common.
Compensatory Swan neck deformity is known to occur.
Chronic Mallet injuries with compensatory swan neck
deformity are reconstructed with SORL reconstruction
techniques . Those chronic deformities which are painful,
arthritic, and interfere with hand function are treated with DIP
fusion
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32. Zone I injury: Surgical
Intervention
Placement of a permanent buried suture
can be avoided by :
A.The tendon ends are incorporated
with the interrupted skin sutures
B.The proximal end of the divided
tendon is advanced into the insertion
site with the use of a pull out suture
tied over a bolster on the finger pad
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33. Zone I injury: Surgical
Intervention
Technique of extensor tendon repair at
the DIP joint , in which the skin and the
tendon are simultaneously
approximated
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34. SORL Reconstruction
 A. A Mallet deformity with
compensatory swan neck deformity
B&C. The Tendon graft is fixed to the
distal phalanx with a pull out suture.
The graft is passed between the flexor
tendon sheath & the neurovascular
bundles palmar to the PIP joint. The
graft is tensioned & anchored into the
shaft of the proximal phalanx
SORL reconstruction is advocated for
correction of a swan neck deformity
which is secondary to a mallet finger
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35. ZONE II INJURY
Extensor tendon width is greater in zone II than zone
I & the extensor mechanism has two lateral bands
which extend the distal phalanx
Lacerations of less than 50% of the tendon cut can
be treated by skin closure alone, rest are repaired by
a pull out suture technique
Typically seen in conjunction with sharp lacerations,
saw injuries, and crushing injuries
The DIP is splinted in extension for 4 to 6 weeks
Turrent Exostosis is a mass of bone formed
secondary to a periosteum injury in a zone II
laceration. This mass limits DIP flexion and resection
is the treatment of choice
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36. Doyle’s repair : Sharp laceration of zone II repaired with a running suture
and over sewn by a Silverskiold cross stitch
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37. Immobilization Of Zone I & II
injuries
Aluminum splint
Stack splint
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38. ZONE III INJURY
Disruption of the extensor apparatus at or just
proximal to the PIP joint results in a loss of extensor
power at the PIP joint
Forced flexion of the PIP joint damages the central
slip of the extensor tendon
After central slip disruption the triangular ligament
stretches over time shifting the lateral bands in a
volar direction
The head of the proximal phalanx ‘buttonholes’
through the extensor mechanism, creating the
Boutonniere deformity
Lateral bands falling volar become PIP joint flexors
instead of extensors while continuing to exert an
extensor force on the DIP joint
Boutonniere deformity can be acute –(closed or
open) and chronic
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39. Boutonniere Deformity Right hand Ring finger
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40. Patho mechanics of Boutonniere deformity: A. Attenuation of the central
slip results in unopposed flexion at the PIP joint; B. With PIP flexion the
lateral bands drift palmar( due to decreased support from the stretched
triangular ligament) to the axis of rotation at the PIP joint
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42. Chronic Boutonniere
Deformity
Burton & Melchior classification:
Stage 1: supple, passively correctable
deformity
Stage 2: fixed contracture: contracted
lateral bands
Stage 3: fixed contracture: joint fibrosis,
collateral ligament & palmar plate
contractures
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43. Treatment plan in Boutonniere
deformity
Acute closed Boutonniere injuries: extension
splinting of PIP joint
Acute open Boutonniere injuries: primary
repair ( Doyle’s, Snow’s, Aiche’s methods)
Chronic Boutonniere deformity: Stage 1 & 2-
therapy regimen of active assisted extension
of the PIP joint combined with passive flexion
of the DIP joint . Stage 3 – options include
Tenotomy, Tendon grafting, Tendon
relocation
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44. Burton & Melchior’s guidelines
for Boutonniere surgery
Boutonniere reconstruction are most successful on
supple joints. If necessary, a joint release can be
performed as a first stage.
An Arthritic joint usually precludes soft tissue
reconstruction. The surgeon should consider either a
PIP joint fusion or Arthroplasty with extensor tendon
reconstruction
Boutonniere deformity rarely compromise PIP flexion
& grip strength. Do not trade extension at the PIP
joint for a stiff finger & a weak hand
Goal of Boutonniere reconstruction is to rebalance
the extensor system by reducing extensor tone at the
DIP joint and increasing tone at the PIP joint
Splinting is an important component of the post
operative care; it may be necessary for several
months
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45. A Bunnell splint is applied to maintain extension at the PIP joint. The strap over
the PIP joint is progressively tightened until the PIP joint is fully extended. The
patient is encouraged to flex the DIP joint.
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46. Reconstruction of Boutonnière
A.The boutonniere deformity with the lateral
bands & ORL volar to the PIP joint
B.Dorsal zigzag incision
C.The ORL is separated from the lateral bands
& a tenotomy of the lateral bands is done
distal to the central slip insertion
D.If active PIP extension is still not possible,
the lateral bands are suture together, dorsal
to the PIP joint
E.Sequence of events
F.The PIP joint is fixed with a transarticular K
wire
G.The mechanics of the reconstruction
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47. Central slip laceration with sufficient tendon to repair with core
suture & over sew with silverskiold epitendinous suture
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48. When the tendon laceration is distal, leaving a small stump of central slip;
the core suture can be passed through a trough in the base of the middle
phalanx
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49. Snow’s technique of central slip
reconstruction ( distally based flap)
Aiche’s technique of central slip
reconstruction (central halves of lateral
bands)[email protected]

50. Littler’s tendon graft
technique: a thin graft is
woven through the base of
the middle phalanx and
through the extensor
tendon to restore extensor
tone to the PIP joint
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51. Extensor Tenotomy for Supple
Boutonniere deformity
Dolphin or Fowler procedure: The
lateral bands are released distal to
the insertion of the central slips . The
lateral resulting proximal migration of
the extensor mechanism reduces
tension at the DIP joint & increases
extensor tension at the PIP joint
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52. Post burn Boutonniere
Defomity
Primary damage is that of the central slip, leading to
the sliding of the lateral bands below the axis of
rotation of the PIP joint
The lateral bands thus become PIP joints Flexors
rather than extensors, and the PIP joint is flexed up
to 90 degrees
The absence of Central slip allows the system to
move proximally resulting in excessive pull on DIP
joint causing its hyper extension
Before surgery its necessary to its necessary to
eliminate the related contractures of other hand joints
There is a constant battle between the options of
Tendoplasty vs Arthrodesis
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53. Pseudo Boutonniere
Deformity
Flexion deformity of PIP joint, often
following an axial load injury
Hyper extension injury to PIP joint
Volar plate avulsion on X-ray with volar
PIP joint tenderness
More common than Boutonniere
deformity
Protected immobilization required
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54. ZONE IV INJURY
Partial zone IV injury is more common than a
complete laceration because the extensor
mechanism is flat & it curves around the
proximal phalanx
Often associated with a proximal phalanx
fracture
Treatment is repair with modified Kessler’s
suture using 4-0 braided polyester
Within 1 week of repair the patient is started
on passive extension & active flexion
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55. Dynamic splint in zone IV
injuries
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56. ZONE V INJURY
A complete division of the extensor mechanism in
this zone is uncommon owing to the width of the
tendon
A partial laceration with division of the central tendon
is common because of the tendon’s prominence over
the metacarpal head
The central tendon is repaired with a grasping suture
& the hand is splinted in wrist extension & 30 degrees
of MP flexion. The IP joint is allowed active motion
Sagittal band injury can also occur in zone V, can be
either open or closed . Treatment of open injuries is
straight forward exploration & repair
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57. HUMAN BITE INJURIES
Partial extensor tendon injuries over the MP joint
(zone V) are often caused by a punch to an
opponent’s mouth, so called clench fist injury or fight
bites
The tendon injury is proximal to the skin laceration
because the MP joint is flexed at the time of injury
Bacterial growth consists of Streptococcus,
Staphylococcus, Bacteroides & E.Corrodens
Treatment consists of prompt surgical exploration of
the wound. The extensor tendon should be split
longitudinally and the MP joint opened, cultured,&
irrigated with antibiotic solution. Repair of lacerations
is deferred ( usually 7 to 10 days) until the infection is
cleared
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58. Closed Sagittal band injuries
(Extensor tendon subluxation)
Result from direct blow, from forced MP joint flexion
or from daily activities such as flicking the finger or
crumpling the paper
Symptoms range from pain & loss of MP joint motion
to extensor tendon snapping or catching during
finger flexion
Acute injuries that are 2 -3 week old can be treated
with extension splinting of the MP joint
Patients who fail splint treatment or who have an
injury more than 3 weeks old should be treated with
direct repair of the Sagittal band
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59. Methods of Extensor hood reconstruction
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60. ZONE VI INJURY
Have a better prognosis than distal injuries
because decreased surface area & increased
subcutaneous tissue lessens adhesion
formation and also there is greater tendon
excursion with no complex tendon
imbalances
Modified Bunnel or Kessler’s core suture
supplanted with epitendinous sutures is the
standard treatment
Complications after zone VI repair are loss of
flexion, loss of extension, & tendon rupture in
the order of frequency
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61. ZONE VII INJURY
There is almost always an associated injury
to the extensor Retinaculum
Point in favor of excision of Retinaculum are
that it improves exposure & prevents friction
between bulky repairs and the retinaculum
while its preservation prevents bow stringing
or subluxation of the extensor tendons
Treatment is same as zone VI in acute cases
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62. Chronic injuries of zone VII
Most common cause is attritional rupture e.g.
EPL rupture after distal radius fracture or with
Rheumatoid Arthritis
Management is difficult as there is no Para
Tenon in this region leading to retraction of
the proximal tendon. Also, since the ends are
frayed, end to end repair is not possible
without unacceptable shortening of the
musculotendinous unit & a loss of flexion
Tendon transfer or a graft is the standard
treatment
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63. Reconstruction after EPL
rupture
Reconstructive options:
1.The Palmaris longus tendon is used
as a intercalated graft
2.EIP is transferred to the distal end of
EPL
3.The Palmaris longus is transferred
around the radial side of the wrist to
the EPL
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64. ZONE VIII INJURY
Includes ruptures of musculotendinous
junction and muscle belly lacerations
Repair of these injuries is complicated
by the difficulty of placing sutures in the
thin fascia overlying the muscle
When repair is not feasible, a side to
side tendon transfer provides the best
means to restore tendon function
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65. ZONE IX INJURY
Penetrating trauma in this region can be
accompanied by nerve injuries making
assessment difficult
A proximal forearm laceration with a loss of
distal muscle group function is probably a
motor nerve injury rather than a tendon
division
Multiple interrupted absorbable sutures are
used to repair the Epimysium & fibrous
intramuscular septum.
Suture repair of muscle lacerations have
virtually no tensile strength. Post op treatment
is 4 weeks of cast immobilization
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66. Swan Neck Deformity
Hyper extension of PIP with
flexion of DIP

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68. Swan Neck Deformity
Cause : Volar plate rupture at the PIP with often
accompanying triangular ligament rupture.
Pathology :Lateral bands drift dorsally and
exacerbate the hyperextension at the PIP joint.
They become ineffective in extension at the DIP
joint and the unopposed action of the profundus
causes flexion at the DIP joint.
Clinically : Causes “jamming” dislocations
Immediately noticeable, if not immobilized will
become surgical finger.
Treatment: involves SORL reconstruction

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69. SURGICAL ASPECTS
ZONE SUTURE TECHNIQUE SUTURE MATERIAL
I & II Splint only none
Skin with tendon (simple) 5-0 monofilament
Tendon suture (Cross stitch) 6-0 monofilament
Pull out tendon 4-0 monofilament
III,IV & V Grasping tendon suture 4-0 braided synthetic
+/- simple or cross stitch 6-0 monofilament
VI,VII & VIII Grasping core suture 4-0 braided synthetic
+ epitenon 6-0 monofilament
Multiple slips to same digit 4-0 braided synthetic
sutured together

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70. Regional anaesthesia
Brachial plexus block ( above the
clavicle):
Inter scalene – anterior or posterior
Supra clavicular – Classic,
Plump bob, Para scalene,
Inter strernocleidomastoid,
Subclavian perivascular

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71. Regional anaesthesia
Infra clavicular approach- Para
coracoid, lateral
Axillary block
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72. LOCAL BLOCKS
Wrist blocks
Median nerve block
Superficial branch of Radial block
Ulnar nerve block
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73. LOCAL BLOCKS
Technique of giving a dorsal digital
block
DIGITAL NERVE BLOCKS
Ring block
Volar block
Dorsal block
Flexor tendon sheath
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74. TOURNIQUET
A penrose drain can be used as a
finger tourniquet
For the upper limb as a whole a
tourniquet is kept at a pressure of 150
-250 mm of Hg for a period ranging
from 45 mins to 2 hours
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75. Techniques
A.Horizontal mattress; B.Figure of 8; C.Kessler’s; D.Modified Bunnell
D
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76. Thin flat tendons repaired in
pairs
When the core diameter of two tendon slips makes a core grasping
suture technically difficult , the two sips can be incorporated into one
repair, A. FIGURE OF EIGHT, B. MODIFIED GRASPING SUTURE
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77. Suture technique for flat broad
tendons
Flat , broad tendons of zone III, IV & V are repaired by A. core suture, B. cross
stitch suture techniques [email protected]

78. IMPORTANT POINTS IN
EXTENSOR TENDON
REPAIR
Extensor tendon suture technique vary according to
the location of the injury & the size of the tendon.
Distal to the MP joint, in zone I to V, the extensor
tendon is wide and flat. In zone VI to VIII, the tendon
is narrow and thick.
A grasping technique is used when the tendon is
large enough to allow placement of sutures.
Suture technique should be chosen to maximize
strength & minimize shortening of the tendon.
Extensor retinaculum when involved should be
preserved
The highest priority of extensor tendon injury is not
regaining full extension. The goal is to increase
motion in the functional range of the patient’s normal
activities.
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79. COMPLICATIONS
Most common complication after tendon repair is the
formation of adhesions between the repair site,
adjacent skin and the bone. The adhesions can
restrict joint flexion as well as extension.
Treatment includes Tenolysis, Capsulotomy or
Collateral ligament release
Gapping
Disruption
Non healing skin site
Scarring
Decreased Joint mobility
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80. PHYSIOTHERAPY
Zone I & II injuries are treated with a static
Splint. Only 1 to 2 mm of tendon excursion is
necessary for DIP flexion, a fact that makes
adhesions at the injury site less of a problem.
Early motion rehabilitation protocols are
recommended for injuries in zone III to VIII
The patient actively flexes the finger followed
by passive extension with rubber band
traction
Children & non cooperative patients are best
treated with immobilization
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