HAND-ANATOMY, MANAGEMENT OF HAND AND FINGER TIP INJURIES 1.pptx

hand trauma

1. MANAGEMENT OF HAND TRAUMA  Presenter: Dr. Bhuwan Rayamajhi Moderator: Dr. Piyush Giri

2. Muscles and Tendons Extrinsic extensors: Lie on the dorsum of forearm and hand. Innervated by radial nerve Function: ECRL + ECRB + ECU serves to extend the wrist. Extensor digitorium communis , extensor indicis proprius and extensor digiti minimi are finger extensors. Three extrinsic extensors assist in thumb motion: abductor pollicis longus, extensor pollicis brevis and extensor pollicis longus.

3. Muscles and Tendons Long flexors (profundus and superficialis) are responsible for flexion of IP joints and are supplements to active flexion of MCP joints. Flexors are located on volar side of forearm and wrist and innervated by median except FCU, FDP to ring and small fingers (ulnar nerve). FCR, FCU and Palmaris longus provide wrist flexion. FDS, FDP and FPL pass through carpal tunnel to provide dual flexion to the fingers and single flexion to the thumb. Flexor digitorium profundus of the index finger is unique and it has an independent muscle belly.

4. Muscles and Tendons The FDS tendon lies superficial to profundus tendon in the palm, splits at the level of proximal phalanx and insert on middle phalanx. The FDP perforates the FDS runs superficially along the length of proximal and middle phalanx and insert at the base of distal phalanx. The flexor pollicis longus inserts at the distal phalanx of the thumb.

5. Intrinsic muscules Divided into 4 groups: Thenar : Abductor pollicis brevis Flexor pollicis brevis Oppenens pollicis Adductor pollics All are supplied by median nerve except adductor pollicis which is supplied by ulnar nerve.

6. Intrinsic muscules Hypothenar muscles: All are innervated by median nerve. Palmaris brevis Abdductor digiti minimi Flexor digiti minimi Oppens digiti minimi Lumbricals originates from FDP tendons and insert on radial aspect of MCP joint Lateral two lumbricals are innervated by median nerve medial two lumbricals are innervated by ulnar nerve Function is flexion of MCP joints and extension of interphalangeal joint

7. Intrinsic muscules Interossei originate from the metacarpals and form the lateral bands with lumbricals function as ulnar and radial deviators of the fingers as well as flexors of the MCP joints and extensors of IP joints

8. Blood supply of hand

9. Nerve supply Median nerve: Runs through carpal tunnel Sensory branch: Palmar cutaneous branch Dorsal digital phalanges 3 1/2 Volar wrist capsule. Volar 3 1/2 digits and lateral palm. Motor branch: Abductor pollics brevis Opponens pollics Flexor pollicis brevis Two lateral lumbricals

10. Nerve supply Radial Nerve: Sensory supply to dorsal 3 1/2 digits via superficial branches .

11. Flexor tendon injuries

12. Introduciton Flexor tendon injuries – common Recovery of satisfactory function – unpredictable, difficult Current trend of end to end surgical repair – multistranded core sutures Success – thorough mastery of anatomy and meticulous surgical technique

13. Anatomy 12 flexor tendons: hand and forearm Finger – FDP, FDS Thumb - FPL

14. Flexor tendon healing: Nutrition – synovial and vascular sources Healing process – early inflammatory, middle collagen production and late remodelling phases Mechanisms of healing of intrasynovial flexor tendons : intrinsic and extrinsic

15. Intrinsic - proliferation of tenocytes and production of extracellular matrix by intrinsic cells Extrinsic – growth of tissues or cell seeding from outside

16. Diagnosis Open injuries – sharp cut or crush Open injuries due to extensive trauma – frequently associated with neurovascular deficit Closed injuries – forced extension during active flexion of the finger- Jersey finger

17. Careful neurovascular examination Flexor tendon injury leads to loss of Active finger flexion Normal finger cascade Resting flexor tone – results extension posturing

18. Imaging Radiograph – should always be taken Closed tendon injury – CT or MRI Ultrasonographic examination – may reveal rupture of tendons.

19. Treatment/ Surgical techniques

20. Primary and delayed primary repairs Primary tendon repair – end to end repair performed immediately after wound cleaning and debridement, usually within 24 hours after trauma Delayed primary repair – repair performed within 3 or even 4 weeks after tendon lacerations. Ideal situation – surgery within a few hours, experienced surgeon readily available

21. Indications of primary flexor tendon repairs Clean-cut tendon injuries Tendon cut with limited peritendinous damage, no defects in soft-tissue coverage Regional loss of soft-tissue coverage or fractures of phalangeal shafts are borderline indications Within several days or at most 3 or 4 weeks after tendon laceration

22. Contraindications of primary flexor tendon repairs Severe wound contamination Bony injuries involving multiple joint components or extensive soft-tissue loss Destruction of a series of annular pulleys and lengthy tendon defects Experienced surgeons are not available

23. Surgical techniques

24. Basic requirement of a tendon repair Sufficient strength Smooth tendon gliding surface with minimal suture (and knot) exposure No gaping of repair site under tension Ease to perform

25. Partial tendon lacerations Less than 60% diameter –does not necessitate core sutures Over 60% - increased risk of triggering, entrapment or rupture Repair of less than 60% laceration – rimming of tendon wound or epitendinous stitches 60 - 80% - core suture through cut portion More than 80% - treated identical to complete laceration.

26. Postoperative care Dorsal blocking splint – wrist flexion 20° to 30°, MCP joint flexion at 50° to 70°, and PIP and DIP joints in full extension Early protective motion – promotes tendon healing Motion of repaired tendons – should be initiated from early postsurgical period.

27. Outcomes Severity of initial injury Timing and quality of the repair Patient underlying medical condition ( affect tendon healing) Quality of postoperative rehabilitation

28. Complications Finger stiffness - most common complication Infection Skin flap necrosis Tendon rupture after repair

29. Extensor tendon injuries Anatomy of the extensor tendons Extensor mechanism consists of extrinsic muscles, which are located on the forearm and intrinsic muscles which are located at the levels of metacarpals. The extensor apparatus is a well-balanced system of interlinking tendons and fibro- ligamentous bands that orchestrate the fine positional movement of each digits. Due to superficial, position of extensor tendons, they are vulnerable to injury and exposure.

30. Extrinsic extensors All extrinsic tendons pass through the six compartments of the extensor retinaculum.

31. Presentation Diagnosis of extensor tendon is often evident. As a general rule: Open lesions should be surgically explored to identify the extent of the injury.

32. Presentation The function of the EDC tendon should be assessed by extension of the MP joint against the resistance. Partial lesion can be missed if the remaining tendon is strong enough to create some extension force. The EPB tendon inserts into the extensor tendon apparatus of the thumb at varying levels and may be able to extend IP joint of the thumb.

33. PRESENTATION If there is questionable rupture of the EPL tendon, it should therefore not be tested by extension of the IP joint. Instead, the patient should be asked to lift the thumb off the table, which will be impossible without an intact EPL tendon.

34. Kleinert and Verdan proposed a system to classify lesions of the extensor tendon appartus into eight zones according to level of injury.

35. References Grabb and Smith’s Plastic Surgery, 9 th edition Fundamental Techniques of Plastic Surgery and their surgical application, 10 th edition