- first performed by Darrach in 1911 in New York City.
- for relief of pain following distal RU disruption and/or RU arthritis;
- for symptomatic malunion of Colle's frx in elderly patients, especially when stiffness is present;
- procedure is generally performed on elderly patients w/ low functional demands;
- young pts w/ symptomatic instability of distal RU after Colle's frx may have better results w/ distal radial osteotomy w/ restoration of length & alignment, or when this is not possible then consider hemi-resection arthroplasty;
- dorsal approach to the wrist
- longitudinal incision is made over distal ulna w/ care to preserve the attachments of the TFCC to the carpi;
- alternatively, approach distal ulna thru the interval between the ECU and FCU;
- carefully place Homan retractors around the ulna, w/ care to avoid injury to the ulnar artery and nerve;
- excise of distal 1-2 cm of ulna (just proximal to the sigmoid notch);
- some surgeons attempt to minimize the amount of bone resected, inorder not to destabilize the distal ulna, and to maintain attachments of pronator quadratus;
- the least amount of bone is excised which is sufficient to restore full motion;
- ulnar styloid process and its attachment to the ulnar collateral ligament may be preserved;
- bevel any sharp edges;
- remnants of the TFCC are opposed to the wrist capsule and the radius;
- remnants of the wrist capsule are anchored to the distal ulna;
- if the ECU is volarly subluxated, it should be relocated and anchored distally over the carpus;
- Stabilizing Procedures:
- if the distal ulna appears unstable, it may be stabilized w/ a distally based strip of ECU tendon pass through a drill hole at the end of the bone;
- the tendon is sutured to itself with the wrist in ulnar deviation;
- ECU/pronator quadratus arthroplasty:
- distally based ECU tendon is attached to the dital ulna and helps prevent radial-ulnar impingement;
- the pronator quadratus arthroplasty helps retard dorsal translation;
- standard approach between the ECU and the FCU tendons;
- pronator quadratus is dissected off of its insertion on the ulna (palmar medial side);
- the pronator is mobilized, and is then transferred over the dorsal surface of the ulna;
- medullary canal of the distal ulna is reamed with a burr, and a drill hole is prepared approximately 1.5 cm proximal to the distal end ofthe ulna;
- harvest one half of the ECU tendon, leaving it attached distally;
- pass the free half of the ECU through the medullary canal of the distal ulna and then back out of the hole made in the side of the ulna;
- flex the elbow and keep the forearm in neutral rotation;
- pass 2 divergent K wires from the ulna to the radius while maintaining a desired amount of radioulnar distance;
- these wires allow soft tissue healing and are left in place for 6 weeks;
- procedure does not produce uniformly good results, especially in younger patients;
- instability of the distal ulnar shaft;
- painful subluxation of the ECU over the transected end of the ulna;
- palmar subluxation or ulnar translation of the carpi;
- radio-ulnar impingement (convergence);
- occurs between stump of the ulna and the ulnar side of radius and is usually accompanied by instability;
- impingement is worsened w/ power grip, and the pronator quadratus seems to be the major deforming force;
- severity of the convergence correlates w/ the amount of resected bone;
- often causes symptoms, but as reported by McKee and Richards, convergence can occur w/o symptoms;
- when this complication occurs, consider the stabilization procedures, described previously;
- case example:
- this patient had convergency type pain, which was thought to be due in part to a contracture of the prontator quadratus
- Dynamic radio-ulnar convergence after the Darrach procedure.
Anterior dislocation of the head of the ulna. Darrach W. Ann Surg. 1912;56:802-803.
Habitual forward dislocation of the head of ulna. Darrach W. Ann Surg. 1913;57:928-930.
Partial excision of lower shaft of ulna for deformity following Colle's fracture. Darrach W. Ann Surg. 1913;57:764-765.
Poor results of Darrach's procedure after wrist injuries.
Results of extensor carpi ulnaris tenodesis in the rheumatoid wrist undergoing a distal ulnar excision.
Rupture of digital extensor tendons following distal ulnar resection.
A modified extensor carpi ulnaris tenodesis with the Darrach procedure.
History of hand surgery