Olecranon Osteotomy

- Discussion:
    - used in conjunction w/ a posterior approach: for fixation of condylar fractures, as well as exposure of distal humeral non unions;
    - olecranon osteotomy can be either non-articularl or trans-articular;
           - usually the non-articular olecranon osteotomy is used for non-articular condylar fractures;
           - trans-articular osteotomy is reserved for articular condylar fractures;

- Intra-articular Osteotomy:
    - as always first elevate the ulnar nerve;
    - before performing olecranon osteotomy, its wise to predrill proximal ulna;
         - 1 cm longitudinal incision is made in the midline of the triceps;
         - 4.5 mm drill is used to make glide hole in proximal frx fragment;
         - golf tee is inserted, and 3.2 mm drill is inserted across distal fragment;
         - 6.5 mm tap is inserted across the frx site;
                - the hole is tapped until resistance is felt, which also marks the proper depth of the 6.5 mm cancellous screw;
    - elevate the aconeus off the olecranon to expose the articular surface;
    - a sponge may be placed across the articular surface for proctection;
    - intra-articular chevron olecranon osteotomy is then performed w/ oscillating saw perpendicular to long axis of ulna 3-4 cm proximal to its tip;
          - the chevron osteotomy prevents rotational malalignment;
          - osteotomy is made in center of olecranon sulcus because this area of olecranon has least amount of articular cartilage;
          - the hyaline cartilage of the proximal ulna is not continuous, but rather lacks cartilage w/ in the mid portion;
                - this is the optimal position for olecranon osteomy;
                - see: anatomy of olecranon;
    - chevron osteotomy is created a w/ thin oscillating saw until the far subchondral surface is reached;
          - the osteotomy should be completed w/ thin-bladed osteotome which cracks articular surface of semilunar notch;
    - cut is completed with osteotome using tension break of articular cartilage and subchondral bone;
          - a freer elevator may be placed over the articular surface for protection;

- Elevation of Extensor Mechanism:
    - residual portions of the capsule are removed;
    - as triceps is elevated on both medial and lateral sides, a small margin of triceps should be left on either side to allow for suture repair at completion of case;
    - proximal part of olecranon may then be elevated w/ triceps, which provides exposure as far as 7.5-10 cm above joint line before radial nerve is threatened
           on the lateral side of the exposure;
           - usually the branch to the brachioradialis will be encountered first;
           - see: posterior approach to the elbow;
    - further exposure is obtained by subluxation of the joint;

- Osteotomy Fixation:
    - 6.5 mm cancellous bone screw (over washer) in combination with a figure of 8 wire may be utilized for fixation of the olecranon osteotomy;
          - the proper screw length is based on the insertion depth of the 6.5 mm tap as it achieves moderate torsional resistance;
          - in small ulna, screw thread may not pass into meduallary cavity of shaft and a long 6.5 mm cancellous bone screw may jam before it achieves a good bite;

- Alternative Fixation:
    - secure osteotomy w/ two oblique 0.045-in (1.143-mm) smooth K wires & tension-band wire;
    - proximal ends of the K wires are carefully bent and anchored into bone;
          - tension wire is placed through a drill-hole in the ulna distal osteotomy and passed under K wires and triceps proximally to create tension band;

- Disadvantages of Osteotomy:
    - disadvantage is that osteotomy must be stabilized at conclusion of operative procedure;
    - non-union of olecranon osteotomy may occur upto 5 % of cases;
    - osteotomy hardware is often painful, requiring removal

The proximal ulna: An anatomic study with relevance to olecranon osteotomy and fracture fixation.

Olecranon Osteotomy for Exposure of Fractures and Nonunions of the Distal Humerus.

The olecranon osteotomy: a six-year experience in the treatment of intraarticular fractures of the distal humerus.

Determining the efficacy of screw and washer fixation as a method for securing olecranon osteotomies used in the surgical management of intraarticular distal humerus fractures.

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Monday, March 16, 2015 10:17 am