- See:
- Rheumatoid Arthritis
- Extensor Tendon Lacerations
- Mallet Finger
- Rheumatoid Wrist
- Teno-synovectomy
- Discussion:
- ulnar side of wrist is most common site of extensor tendon ruptures;
- pathophysiology: (caput ulnae syndrome)
- this most often due to attritional changes due to caput ulnae syndrome;
- volar subluxation of the ECU causes in loss of ulnar deviation and extension and the wrist begins to deviate radially;
- this brings the ulnar-sided extensor tendons directly over the prominent ulna;
- radial deformity of wrist results from volar subluxation of ECU and increases potential for attrition ruptures of extensor tendons (Vaughn-Jackson syndrome);
- futher, erosion of the distal ulna causes its edge to sharpen leading to rupture of extensor tendons;
- clinical findings:
- dorsal subluxation of ulna associated w/ tenderness on resisted extension of thumb & fingers should raise possibility of tendon rupture;
- rupture of EDC to 4th & 5th digits from caput ulna
- tendons to the middle and index fingers are less often ruptured;
- thickening of the dorsal synovium is also present;
- patients will lose tenodesis effect with wrist flexion and extension;
- EDQ rupture (w/ intact little EDC):
- EDQ tendon is most prone to rupture in a patient with rheumatoid arthritis of the wrist;
- rupture is diagnosed with the Texas long horn sign, in which the index and little finger are extended while ring and little fingers are flexed;
- this requires intact extensor indicis and EDQ tendons, respectively;
- EPL rupture:
- commonly injured is EPL, where it passes over Lister's tubercle,
- deformity at level of MP joint of thumb may occur secondary to rupture of the EPB and displacement of the dorsal hood;
- diff dx:
- failure of digit extension from chronic dislocation of MCP
- pt can maintain extension achieved passively, also use Bouvier's test
- PIN syndrome:
- tenodesis effect present - not present with rupture;
- trigger finger (no passive movement possible);
- Treatment Options
- Treatment Considerations:
- caput ulnae syndrome
- needs to be adressed at the time of tendon repair/reconstruction;
- radial deviation of the wrist that is passively correctable may not require treatment;
- Primary Tendon Repair:
- dorsal approach to the wrist;
- should be performed early (within 4-6 wks);
- for a single tendon rupture, end to side repair is prefered using adjacent extensor tendon;
- do not expect execellent individual function;
- when possible the repaired tendon should be passed above the extensor retinaculum to avoid scarring;
- alternatively consider use of a free jump graft (palmaris longus) for tendon repair;
- Tendon Transfers:
- when ruptures occur proximal to the junctura, the tendon will contract which precludes a primary repair (in delayed cases);
- primary repair of contracted tendons may lead to loss of finger flexion and loss of flexion;
- ensure that there is passive ROM (w/ full extension) prior to managing this condition;
- transfers (EIP to EDQ & ring finger EDC to long finger) are best choice since tendon grafts may become adherent;
- multiple ruptures:
- multiple ruptures pose a severe problem;
- combined extensor tendon ruptures to the ring and little fingers;
- EIP is not strong enough to extend more than a single digit, and most often, the proprius is transfered to the EDQ;
- EIP is harvested just proximal to the saggital band insertion;
- extensor slip(s) to the ring finger are then transfered to the EDC of the long finger;
- always check the tenodesis effect following tendon repair or transfer;
- triple rupture:
- FDS from ring finger can be rerouted to the dorsum of the hand and will provide satisfactory extension;
- free tendon graft:
- outcomes are controversial but good results are reported in the litterature;
- ref: The treatment of ruptures of multiple extensor tendons at wrist level by a free tendon graft in the rheumatoid patient.
- adjusting tension:
- tension is adjusted so that the fingers come out into extension when the wrist is flexed 20-30 deg;
- w/ radial deviation deformity of the wrist, the ECRL can be transferred to extensor carpi ulnaris;
- w/ a stiff wrist & more advanced disease, radiolunate arthrodesis can be used & is more predictable;
- EPL rupture:
- commonly injured is EPL, where it passes over Lister's tubercle,
- deformity at level of MP joint of thumb may occur secondary to rupture of the EPB and displacement of the dorsal hood;
- management:
- avoid tendon repair if articular surface is severely damaged;
- consider EIP transfer;
- joint arthrodesis rather than direct repair of tendon improves strength & maintains f(x)
Attrition ruptures of tendons in the rheumatoid hand.
Rheumatoid wrists treated with synovectomy of the extensor tendons and the wrist joint combined with a Darrach procedure.
Year Book: Long-Term Results of Extensor Tendon Repair.
Biomechanical characteristics of extensor tendon suture techniques.
Long term hand function without long finger extensors: A clinical study.