Ape thumb deformity to publish

DEFORMITY OF HAND DUE TO LOSS OF OPPOSITION OF THUMB

1. Ape thumb deformity Dr. M KASI VISWANADHAM DEPT. OF ORTHO RMC ,KAKINDA

2. According to evolutionary biologists, one of the more singular factors elevating man as a higher mammal , as compared to any other, is the modification in the functional capability of the thumb . The human thumb stands alone in its talent to 'oppose'. Anatomically, 'opposition' implies the movement by which you can touch the tip of your thumb to the tips of other fingers of the same hand. No animal except the human kind has a truly opposable thumb

3. Ape thumb deformity who cannot move the thumb away from the rest of the hand due to paralysis of thenar muscles due to median nerve injury or polio or leprosy

4. Anatomy of median nerve The median nerve is derived from medial  and  lateral cords of the brachial plexus It contains fibres from all five roots (C5-T1). After originating from the brachial plexus in the  axilla , the median nerve descends down the arm, initially lateral to the brachial artery .

5. Halfway down the arm, the nerve crosses over the brachial artery, and becomes situated medially. The median nerve enters the anterior compartment of the forearm via the cubital fossa .

6. In the forearm, the nerve travels between the flexor digitorum profundus and flexor digitorum superficialis muscles. The median nerve gives rise to two major branches in the forearm: Anterior interosseous nerve  Palmar cutaneous nerve  Innervates the skin of the lateral palm.

7. The median nerve enters the hand via the  carpal tunnel,  where it terminates by dividing into two branches: Recurrent branch  – Innervates the thenar muscles. Palmar digital branch  – Innervates the palmar surface and fingertips of the lateral three and half digits. Also innervates the lateral two lumbrical muscles.

8. Motor Functions The median nerve innervates the muscles in the  anterior forearm , and some intrinsic hand  muscles. The Anterior Forearm innervates muscles in the superficial and intermediate layers: Superficial layer:  PT, PL,FCR Intermediate layer :FDS The median nerve also gives rise to the anterior interosseous nerve, which supplies the deep flexors: Deep layer:  lateral half of FDP,FPL,PQ

9. The Hand Innervates some of the muscles in the hand via two branches. The  recurrent branch  of the median nerve innervates the  thenar muscles The  palmar digital branch  innervates the lateral two  lumbricals  – these muscles perform flexion at the metacarpophalangeal joints of the index and middle fingers

10. Sensory Functions cutaneous innervation of part of the hand. This is achieved via two branches: Palmar cutaneous branch  – Arises in the forearm and travels into the hand. It innervates the lateral aspect of the palm. This nerve does not pass through the carpal tunnel, and is spared in carpal tunnel syndrome. Palmar digital cutaneous branch  – Arises in the hand. Innervates the palmar surface and fingertips of the lateral three and half digits.

11. Median nerve injuries are classified as high or low depending on whether the lesion is proximal or distal to the origin of the anterior interosseous nerve in the proximal forearm. In low injuries , the thenar intrinsic muscles innervated by the median nerve APB opponens pollicis & superficial head of the FPB are paralyzed. In high injuries in addition all flexor muscles except FCU & medial half of FDP are involved

12. Movements of thumb

13. thumb opposition Thumb opposition is a complex movement requiring trapeziometacarpal joint Abduction of the thumb from the palmar surface of the index finger Flexion of the metacarpophalangeal joint Internal rotation or pronation Radial deviation of the proximal phalanx Thumb motion toward the fingers.

14. Opposition of thumb

15. Axial thumb rotation, usually 90 degrees of pronation and 60 degrees of supination , occurs on the spheroid area of the saddle-shaped trapezial articular surface The prime muscle of thumb opposition is the APB , although both the opponens pollicis and FPB also produce some opposition.

16. Tendon Transfers Steindler is credited with performing the first opponensplasty in 1917. He attached a radial slip of the FPL tendon onto the dorsum of the base of the thumb proximal phalanx. To maximize thumb opposition, Bunnell recommended passing the transferred tendon through a pulley on the ulnar border of the wrist so that it ran subcutaneously across the palm to its thumb insertion

17. A theoretic alternative to opponensplasty is nerve transfer, joining the anterior interosseous nerve in the distal forearm to the thenar branch of the median nerve, possibly with an intervening nerve graft.

18. Preoperative planning To restore thumb function properly deformities or disabilities of thumb must be correct preopertively

19. As a substitute for opposition adduction and extension of the thumb occur as a single function in which the flexed tip of the thumb is brought against the base of the proximal phalanx of the index finger by the pull of the long thumb extensor toward Lister’s tubercle.

20. To pick up an object Abduction of shoulder Elevating the elbow Pronation of wrist Pinch occurs at the base of a finger instead of at its tip

21. The long thumb extensor tendon, acting as an adductor, gradually migrates into the web space between the thumb and index finger Fixed adduction and external rotational deformity of the thumb must be corrected

22. Dividing the fascia in the web space between the index and thumb metacarpals Z- plasty of the web Rotational osteotomy and release of the web space Arthrodesis of the 1 st carpometacarpal joint Excision of the trapezium

23. To restore thumb opposition functionb satisfactorly Tendon transfers to the long thumb flexor long thumb extensor long thumb abductor may be necessary to stabilize the thumb dynamically if the transfer

24. Selection of Motor for Transfer must be expendable and strength and potential excursion should be similar to that of the APB and OP

25. PULLY DESIGN If a tendon transfer does not run in a straight line, increased force is expended to overcome friction True thumb opposition is best restored by transfers that run subcutaneously across the palm parallel to the APB muscle All extrinsic opponensplasties should pass around a stout, fixed pulley in the region of the pisiform on the ulnar border of the wrist.

26. In the area of the pisiform Under or through the transverse carpal ligament Through Guyon’s tunnel Around the palmar fascia Around the PL Around the FCU tendon 

27. Opponensplasty Insertions single and dual insertion techniques In single insertion tech Attaching the opponensplasty to the APB insertion on the radial aspect of the thumb MP joint---- isolated median nerve palsy Dual insertions into the APB insertion and either the dorsal MP joint capsule or the thumb extensor expansion- --- combined median and ulnar nerve palsies

28. Abductor pollicis brevis tendon Extensor pollicis brevis Extensor pollicis longus Dorsoulnar base of thumb proximal phalanx Thumb metacarpal neck Adductor pollicis tendon Superficial head of flexor pollicis brevis tendon

29. Sublimus opponenplasty EIP opponenplasty Abd . Digiti mini opponenplasty PL opponenplasty

30. Sublimus opponenplasty First described by Krukenberg in 1921 Bunnel in 1924 described sublimus transfer and emphasized and defined the role of pully in this transfer Thompson 1942 Riordan 1960 Brand 1966

31. Bunnell's Opponensplasty Motor unit ring finger sublimus tendon Pulley---FCU tendon fixed pulley Insertion site--- dorsal ulnar cortex to the radial cortex of the base of the proximal phalanx

32. Royle -Thompson Opponensplasty Motor unit ring finger sublimus tendon Pulley---- distal transverse carpal ligament ulnar border of the palmar aponeurosis Insertion site--- APB insertion site

33. RIORDAN Opponensplasty Motor unit ring finger sublimus tendon Pulley--- FCU tendon fixed pulley Insertion site--- APB insertion site

34. BRANDS Opponensplasty Motor unit ring finger sublimus tendon Pulley---- GUYONS canal Insertion site----by two slips one into ulnar side MCP another into APL & EPB tendons

35. Extensor Indicis Proprius Opponensplasty Described by Burkhalter The EIP opponensplasty is popular in high median nerve palsy and other situations in which the ring and middle finger FDS tendons are unavailable. It is increasingly preferred to superficialis transfer in low median nerve palsies because it does not weaken grip and causes little if any functional disability Burkhalter W, Christensen RC, Brown P: Extensor indicis proprius opponensplasty . J Bone Joint Surg Am 1973; 55:725-732

36. Abductor Digiti Minimi Opponensplasty The ADM opponensplasty described independently by Huber and Nicolaysen Popularized by Littler and Cooley Improves the hand's appearance by increasing the bulk of the thenar eminence. Littler JW, Cooley SGE: Opposition of the thumb and its restoration by abductor digiti quinti transfer. J Bone Joint Surg Am 1963; 45:1389-1484.

37. Littler transfer of abducto digiti quinti to restore opposition.A , Two skin incisions.Intervening skin (shaded area) Is undermined, creating pocket to receive transfer. B, AnatomY of abductor digiti quinti . Neurovascular bundle is located proximally on deep surface of muscle. Muscle inserts on proximal phalanx (1) and extensor tendon (2) of little nger . C,Origin of muscleis freed from pisiform but not from exor carpi ulnaris tendon. Muscle is folded over about 170 degrees and is passed subcutaneously to thenar area, and its two tendons of insertion(1 and 2) are sutured to abductor pollicis brevis tendon. .

38. Palmaris Longus Opponensplasty The Camitz palmaris longus opponensplasty is a simple transfer that is usually performed for loss of abduction and opposition occurring as a complication of severe carpal tunnel syndrome.

39. Postoperative Management of Opponensplasty The thumb is immobilized in opposition for 3 weeks after most opponensplasties , and the wrist should also be immobilized if the tendon transfer crosses the flexor surface of this joint

40. Thank you