Ulnar impingement syndrome is an idiopathic or acquired ulnar orthotropic variant causing cartilage lesions in the carpometacarpal joint, usually associated with degenerative changes in the TFCC, lunate, and deltoid cystic changes. The clinical manifestations are pain on the ulnar side of the wrist, limitation of motion and loss of grip strength. Short distal ulnar osteotomy is one of the classic procedures for ulnar impingement syndrome.
Although different osteotomy approaches and planes have been reported in the literature, it is more widely accepted that oblique osteotomy has a significantly better bone healing time than transverse osteotomy.
The widespread use of the Rayhack ulnar oblique osteotomy system has effectively reduced the difficulty of intraoperative osteotomy and internal fixation, and has certain advantages in terms of fixation strength, postoperative bone healing rate, and healing time, but the high cost has prevented the widespread use of this system. In this paper, we present our clinical experience in the treatment of ulnar impingement syndrome by using a modified technique of oblique osteotomy shortening with a common compression locking plate and internal fixation with tension screws, combined with arthroscopic TFCC and synovial debridement in the absence of the Rayhack ulnar oblique osteotomy system.
Surgical method Arthroscopic exploration: Arthroscopy is routinely used in patients with preoperative patient MRI suggestive of TFCC injury or cystic changes of the lunate bone (see Figures 2-3). Considering the possible effect of traction on osteotomy, arthroscopy is usually performed before ulnar osteotomy. 2 patients with severe ulnar orthogonal variation were osteotomized and 5lb traction was applied to the wrist joint for arthroscopy. The patients were placed in the supine position with the affected limb abducted, and after brachial plexus anesthesia, a routine sterile towel was laid and a sterile tourniquet was applied to the upper arm. The upper arm was wrapped with a small square towel and cotton pad and secured to the operating table with self-adhesive tape, and another cotton pad was used to protect the ulnar aspect of the elbow joint with longitudinal traction of 2-4 fingers and a traction weight of 10lb. Anatomic landmarks were drawn to mark the Lister’s node, ulnar carpal extensor tendon, and 3/4, 4/5, and 6U approaches. First, 10 ml of saline was injected through the 3-4 approach into the carpal cavity using a 15 ml syringe. The skin was then incised transversely approximately 25px long to create the 3-4,4-5 access, while an outflow channel was created at 6U with an 11-gauge injection needle. Degenerative changes associated with ulnar impingement syndrome often occur in the central perforation of the TFCC, and arthroscopic treatment includes debridement of the free edge of the TFCC and debridement of the inflamed synovium. Care is taken to protect the stable structures around the periphery of the TFCC, and finally the TFCC margin is repaired with a radiofrequency ablation probe and hemostasis is achieved.
Oblique ulnar osteotomy shortening A longitudinal 200px-long incision was made at the ulnar margin of the forearm, the skin and subcutaneous tissue were cut, the ulna was exposed along the ulnar carpal extensor tendon and the ulnar carpal flexor tendon, the palmar margin of the ulna was free, part of the distal rotary anterior muscle was cut, and the ulna was osteotomized at the level of about 6-175px proximal to the ulnar tuberosity. After placing the plate proximally, a line was drawn with a pen along the long axis of the plate, and then a parallel line of 45 degree oblique row osteotomy was marked on the proximal side of the distal third hole, and the pen was cut to fill 1/2 of the circumference of the osteotomy, then the distal screw was loosened, and the diagonal row bone piece was cut along the drawn osteotomy line with an electric saw. Then the distal screws were tightened and the proximal plate was pulled until the fracture end was aligned, paying attention to maintaining the longitudinal axis of the ulna, fixing the plate with the proximal end of the ulna, and putting a compression screw in the fifth hole with an eccentric hole. The remaining two holes were then drilled for each of the distal and proximal ends and locked screws were placed. Intraoperative C-arm examination was performed to determine the height of the ulnar tuberosity after osteotomy and the alignment of the fracture line. The wound was closed with electrocoagulation and absorbable wire layer by layer. A negative pressure drainage tube was routinely placed. (See Figure 4-6) Postoperatively, the forearm was restrained in a plaster cast and the affected limb was suspended to facilitate the reduction of swelling, and early training of finger flexion and extension was performed.