Tendon repair

Brief description of tendon & its repair

1. General Principles Of Tendon Repair – Dr Monitosh Paul (dept of Surgery, SMCH)

2. Tendon Anatomy Tendon Healing Tendon injury Principles of Repair Repair Techniques Rehabilitation Objectives:

3. Tendon Anatomy Tendon: • Fibrous connective tissue that attaches muscle to bone and transfers forces generated by muscle to bone that produces movement of joint Composition: Cellular(20%) – tenocytes & macrophages • Extracellular components(80%) – 70% -water 30 % : 95% type1 collagen 5% GAG + proteoglycans (aggrecan & decorin )- enhance water-binding capability

4. Paratenon covered tendons e .g., patellar, Achilles tendons rich vascular supply so heals better often injured due to trauma Sheathed tendons e.g ., hand flexor tendons less vascularized with avascular areas that receive nutrition by diffusion often injured due to laceration and at risk for adhesions Depending upon coverings

5. Microanatomy of tendon

6. Pulley system : (flexor compartment of digits) Intermittent fibrous condensations that exist along the tendon sheath to secure the tendon to the adjacent bone • Digits 1-4 contain: 5 annular pulleys (A1 to A5) 3 cruciate pulleys (C1 to C3) (A2 and A4 are the most important pulleys to prevent flexor tendon bowstringing) • Thumb contains 2 annular pulley

7. Tendon nutrition 1. Blood supply From segmental vessels arising from surrounding vessels   - In digits, flexor tendons through vincula ; these are folds of mesotenon through which run the small vessels that penetrate the tendons 2. Synovial fluid: Supplies sheathed tendons Produced within tenosynovial sheath

8. Vincular system  Nutrition of tendon  Suspensory ligament of tendon  Stabilization of tendon

9. FLEXOR ZONES OF HAND ( Verdan’s zones) : 5 zones ZONE I: contains only FDP tendons Extends from just distal to insertion of FDS tendon to site of insertion of FDP tendon. ZONE II: ( bunnell’s “no man’s land”) critical area of pulleys Contains both FDP & FDS tendons Between distal palmar crease & insertion of superficialis tendon

10. ZONE III: Comprises area of lumbrical origin Between distal margin of transverse carpal ligament & beginning of critical area of pulleys or 1 st annulus. ZONE IV: Zone covered by transverse carpal ligament ZONE V: Zone proximal to transverse carpal ligament and include forearm

11.  Surgical repair or re-attachment of FDP to bone

12. Goal of tendon healing: Re establish tendon fiber continuity Restore gliding mechanism between tendon and surrounding structure Obtain a satisfactory return of digital motion   Two Forms of Tendon Healing : – Intrinsic healing • through the activity of the fibroblasts derived from the tendon. – Extrinsic healing • by proliferation of fibroblasts from the peripheral epitendon • adhesions occur because of extrinsic healing of the tendon and limit tendon gliding within fibrous synovial sheaths TENDON HEALING

13. Tendon injuries are common in trauma cases presenting to Casualty; they are usually open injuries requiring surgical intervention. The neurovascular injury may be associated with the tendon injury, so have to r/o NVB injury before repairing tendon . TENDON INJURY

14. Tendon injury may be classified as : Open or closed, sharp or blunt, and traumatic or degenerative, based on nature and etiology of injury Extensor or flexor, based on the tendons are involved CLASSIFICATION OF TENDON INJURY

15. Open injuries require primary surgical treatment for exploration, lavage and repair if indi cated. Ultrasound scanning may be used to locate the proximal end of the tendon but not as routine CLASSIFICATION OF TENDON INJURY

16. Closed tendon injuries: Shearing stress to the tendon may result in closed tendon injuries eg. : mallet fingers, Boutonniere deformities and avul sions , ultrasound scanning is useful to know level of injury , also for measurement of gap between the tendon ends and to identify pulley lesions and inflamma tory processes . CLASSIFICATION OF TENDON INJURY mallet fingers Boutonniere deformities

17. Open or closed tendon injuries may be partial or complete When movement is present but painful this can indicate a partial tendon injury In complete tendon injury , generally movement is restricted COMPLETE AND PARTIAL TENDON INJURY

18. 1. Primary repair: Golden period With in 24hrs in a clean wound best results 2 .Delayed primary repair 1-10 days Done: suspicion of infection , viability questionable or came late 3. Secondary repair 10-14days up to 4wks 4. Late secondary After 4 wks Delay several days if wound infected TENDON REPAIR

19. Incision (Brunner incision) TENDON REPAIR

20. TENDON REPAIR Ideal • Gap resistant • Strong enough to tolerate forces generated by early controlled active motion protocols • 10-50% decrease in repair strength from day 5-21 post repair in immobilized tendons • This is effect is minimized (possibly eliminated) through application of early motion stress • Minimal bulk • Minimal interference with tendon vascularity

21. Strickland stresses six characteristics of an ideal tendon repair: (1) easy placement of sutures in the tendon, (2) secure suture knots, (3) smooth juncture of tendon ends, (4) minimal gapping at the repair site, (5) minimal interference with tendon vascularity, and (6) sufficient strength throughout healing to permit application of early motion stress to the tendon. TENDON REPAIR

22. Direct repair : • if laceration is more than 1 cm from insertion Tendon advancement: • if the laceration is less then 1 cm from insertion. TENDON REPAIR

23. Ideal Suture material: Non reactive Pliable Small calibre (4-0) for core sutures and (6-0) for epitendon Strong Easy to handle Common material: Polyester ( Ethibond ), Nylon, prolene TENDON REPAIR

24. Suture configuration 3 Groups Group 1 (e.g. : simple sutures) • the suture pull is parallel to the tendon collagen bundles, transmitting the stress of the repair directly to the opposing tendon ends. • Weakest

25. Group 2 (e.g. : Bunnell suture) • stress is transmitted directly across the juncture by the suture material and depends on the strength of the suture itself. Group 3 e.g. : Pulvertaft technique (fish-mouth weave); • sutures are placed perpendicular to the tendon collagen bundles and the applied stress • Strongest & most suitable

26. Suture configuration Modified suture configs. Multiple-strand modifications • Savage (six strands) • Lee (four strands) The Tang and Cruciate repairs • better tensile strength and elastic properties A four-strand adaptation of the Kessler repair • significantly stronger than the Kessler technique

27. DEPENDING UPON APPROACHES • Epitenon-first technique 22% stronger than the modified Kessler technique • Circumferential suture : Interlocking horizontal mattress suture • greatest resistance to gap formation, • highest stiffness best overall Suture configuration

28. Suture technique • End-to-End • End-to-Side • Tendon-to-Tendon • Tendon-to-Bone

29. End to end technique Kessler & Modified Kessler Bunnel Crisscross Kleinert modification of Bunnel Tajima Strickland (modified Kleinert-Tajima) Fishmouth ( Pulvert ) Roll Suture

30. End to end technique

31. SUTURE TECHNIQUE (End-to-End) Kessler • Mainly used for tendon repair in the fingers and palm. • disadvantage: knots being left exposed on the tendon surface Modified Kessler (Smith-Evans modification ) Advantage: • A single piece of suture material is used. • knot is left in the cut surface of the tendon. • minimize the problem of exposed suture material Disadvantage: difficulty to achieve satisfactory approximation of the tendon ends.

32. Kessler Technique: 1 3 4 6 5 2

33. SUTURE TECHNIQUE (End-to-End) Crisscross Bunnel

34. SUTURE TECHNIQUE (End-to-End) Kleinert ( Bunnel crisscross modification) • easier, less intratendinous ischemia, gap formation are possible.

35. SUTURE TECHNIQUE (End-to-End) Tajima Since two knots are made at cut ends, easy to approximate even the tendons at difficult locations.

36. SUTURE TECHNIQUE (End-to-End) • Strickland (Modified Kessler-Tajima)

37. Strickland 1995 : (modified) Strickland 1995 : (modified) Strickland 1993

38. SUTURE TECHNIQUE (End-to-End) Fishmouth ( Pulvertaft ): • A tendon of small diameter can be sutured to one of large diameter. • commonly used to suture tendons of unequal size.

39. SUTURE TECHNIQUE (End-to-End) Tendon and skin sutured together • Useful for suturing extensor tendons over or near the metacarpophalangeal joints Roll-Stitch

40. SUTURE TECHNIQUE (End-to-Side) • Used in tendon transfers • when one motor must activate several tendons.

41. Tendon-to (other) Tendon Suture Chapter 66 : Flexor and Extensor Tendon Injuries . Campbell’s Operative Orthopaedic , 12th. Ed

42. Tendon-to-Bone Attachments Chapter 66 : Flexor and Extensor Tendon Injuries . Campbell’s Operative Orthopaedic , 12th. Ed

43. Tendon Attachment in Fingers Chapter 66 : Flexor and Extensor Tendon Injuries . Campbell’s Operative Orthopaedic , 12th. Ed

44. One method of attaching tendon to bone • A, Small area of cortex is raised with osteotome. • B, Hole is drilled through bone with Kirschner wire in drill. • C, Bunnell crisscross stitch is placed in end of tendon, and wire suture is drawn through hole in bone. • D, End of tendon is drawn against bone, and suture is tied over button

45. COMPLICATIONS Short term: Infection Injury to neurovascular structures or pulley system Abnormal scarring Long term: Adhesion Rupture Joint contracture triggering

46. Rehabilitation Goal : -promote intrinsic tendon healing & minimize extrinsic scarring to optimize tendon gliding & functional range of motion Early post-repair motion stress – biologically alter the process of scar formation and maturation at the repair site such that collagen is laid down parallel to the axial forces (increase strength), and decrease adhesions i.e., tendon adhesions are stretched (increased tendon glide)

47. Methods of post-op tendon management are: • Immobilization: Complete immobilization of tendon for 3 ½ weeks after Surgery; but greater chances of production of scar adherence; greater incidence of tendon rupture • Controlled passive motion: passive flexion and extension followed by active extension and passive flexion • Early active motion : early active extension but passive flexion, Method minimizes scar adhesions while enhancing tendon nutrition and blood flow