At the end of this lecture, you should be able to:- Understand and describe the anatomy of the flexor tendon system in the hand and its relevance in surgery Describe and relate the normal physiology of the tendon and its implications in injury Understand the reaction of tendon to injury and its healing process and its implications in surgery and rehabilitation

1. Management of
Flexor Tendon Injuries
Mr Vaikunthan Rajaratnam
Senior Consultant Hand Surgeon
vaikunthan@gmail.com www.handsurgerymanual.com
NuwaraEliya Workshop SL19 21 Dec 2019 - Webinar

2. http://tinyurl.com/HandTendon

3. Flexor tendon anatomy, biology
of tendon healing

4. Learning Objectives
• Understand and describe the anatomy of the
flexor tendon system in the hand and its
relevance in surgery
• Describe and relate the normal physiology of
the tendon and its implications in injury
• Understand the reaction of tendon to injury
and its healing process and its implications in
surgery and rehabilitation

5. ANATOMY
• Flexor sheath/pulleys
Our results demonstrate that A2 and A4 absence did
not produce major bowing if adjacent annular pulley
are intact. This has significant impact during flexor
tendon surgery in zone 1 and 2 and the practice of
venting of A2 and A 4 pulleys.

8. Micro-anatomy

10. ANATOMY
• Tendon nutrition
1. Blood supply provided
through the vincular
circulation
2. Synovial fluid
• FPL does not have a
vinculum >>> can
tolerate more tendon
advancement without
disturbing its blood supply

11. Tendon Healing
• Phases of healing
1. Inflammatory; Week 1
2. Fibroblastic; week 2-4
3. Remodelling; > week 4
• Tendon repair is the
weakest at 2 week

12. Tendon Healing
Three mechanisms
1. Extrinsic: From surrounding tissue (epitenon
fibroblast), for gap healing
2. Intrinsic: Within the tendon (tenoblast,
stimulated by movement
3. Combination

13. Assessment
• ATLS
• History:
1. Nature; knife, glass,
saw, roller, etc.
2. Position of the finger
3. Date and time
4. Environment

14. Assessment
• Previous Hx: - Injury
- Soft T. Contracture
- Joint stiffness
- Nerve dysfunction
• PMH; DM, skin conditions, medication,…
• SH: Alcohol, smoking, occupation (recon.)
Socio-economic background

15. Assessment
Clinical Examination
Look …..
• Hand/Finger posture (Cascade)
• Both tendon >> full extension
• FDP only >>> extended DIP
• FDS only >>>> No change

16. Assessment
Feel ….
• Empty synovial sheath
• Loss of tendon tension
Move ….
• No tenodesis effect in
passive wrist movement
• Gentle compression on
forearm (ulnar half at
the junction middle and
distal thirds)

17. Assessment
Beware
• Independent FDP index >>>(Pulp to pulp test)
• Tendon anatomical variation: - Deficient FDS
little finger (35%)
- No FDP little finger
• Cut FDP at the wrist >>> normal action
• Partial cut; - Common in FPL
- Painful
• Neuro-vascular injuries
• Others

18. Assessment
Active movement
• FDP
• FDS
• FPL

19. Assessment
X-ray
• Avulsion fracture
• F.B
• Other injuries

20. Zone 1
• Leddy type I – treat within 3 weeks
• type II and III treatable even after 6 weeks.
• Ultrasound helpful in locating the proximal
stump.
• Microsuture anchors or ORIF if bone fragment
• Ensure tendon-bone contact before final knot-
tying.
• too tight repair - quadrigia.
• > Two-strand repair techniques

23. Leddy Packer Type III

26. A 2, 4 and 6 core tendon suture of 4/0 nylon and standard 6/0 epitendinous sutures
were placed by a consultant hand surgeon on the intact FDP tendon in Zone 2
• The increase in volume of the
tendon by placement of the suture
• space between tendon and pulley in
the flexor sheath
• complete obstruction of the tendon
passage through the pulley system
after sutures
Index finger/ A0:
Volume of pulley 386.3 mm3
volume of tendon + suture 287.1mm3
Little finger/ A1:
Volume of pulley: 124.9 mm3
Volume of tendon + suture: 148.3 mm3

27. Zone 2
• < 3 weeks old delayed Primary repair
• >6 weeks old - contraindication to attempt primary repair.
• A pediatric No. 8 feeding tube for retrieval
• strong repair site vs gentle passive range-of-motion therapy
• < 1 cm of FDP stump is remaining, FDP advancement and repair to
bone should be considered.
• Lacerations of the slips of the FDS require different sutures,
techniques, and needles than do FDP lacerations.
• "Active" range of motion after surgery has not been shown to be of
benefit.
• Frayed tendon end debridement
• A2 and A4 myth??

28. Tendon Rehab
https://www.youtube.com/watch?v=P5GuO2Kb3sI

29. Outcomes

39. 2nd Stage

45. Results 2 stage graft
https://www.youtube.com/watch?v=By5LOOKtvO0

46. Hand Surgery Education
• www.handsurgeryedu.com
• http://handsurgerymanual.com/
• https://www.facebook.com/handsurgeryedu
• https://twitter.com/handsurgeryedu
vaikunthan@gmail.com