Methods
Patients
A retrospective analysis of the patient database was conducted to identify the olecranon fractures that were treated with central tension plates with sharp hook at a single surgical center from August 2007 to December 2008. Patients were considered for inclusion in the study if they met the following criteria: age at least 18 years or older, underwent surgery for an olecranon fracture and a central tension plate with sharp hook was used, and if they were followed up for more than 12 months. Patients were excluded from this study if they sustained pathological fractures or previous fractures of the proximal ulna.
Prior to surgery, all patients were educated regarding the central tension plate, and informed consent was obtained from each patient. The Institutional Review Board of the Third Hospital of Hebei Medical University approved the study after thorough examination and verification.
The Structure of Central Tension Plate With Sharp Hook
The central tension plate with sharp hook has obtained the Certificate of Invention Patent (Certificate No. 649355, Patent No. ZL 2008 1 0079748.X). Distally to proximally, the plate consists of a low profile angle-plate shaped body, then a gourd-shaped component, and finally a sharp hook (Figure 1). The plate is placed on the dorsal surface of the proximal ulna rather than the lateral surface. The angle of the plate body changes gradually from 110 degrees proximally to 80 degrees distally, which corresponds with the anatomical morphology of the ulna crest. The gourd-shaped proximal component of the plate is designed specially to contour to the olecranon. There are three holes in the proximal component of the plate, which are used to permit multiple-angle insertion of screws to repair comminuted fragments. The central tension plates used in the current study are not locking ones.
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Figure 1.
The anterior view of the central tension plate with sharp hook.
Operative Technique
A sterile tourniquet is placed on the upper arm after skin preparation and draping. A longitudinal posterior skin incision is made to expose the olecranon. The dorsal surface of the proximal ulna is exposed far enough to accommodate the plate. If present, any impacted articular fragment is elevated and any coronoid fracture is reduced and provisionally fixed to the ulna with one or two Kirschner wires. After primary reduction and provisional fixation of the olecranon fracture, the plate is placed on the dorsal tension surface of the proximal ulna. The proximal component of the plate matches the contour of the olecranon. The sharp hook is inserted into the triceps tendon just over the tip of the olecranon. The plate is held in position and screw holes distal to the fracture line are drilled, measured, and tapped. Cortical screws are inserted into the oval plate holes but not fully tightened to permit sliding of the plate to compress the fracture fragments. The trajectories for the cortical screws are slightly medial or lateral to the central line of the plate to avoid entering the proximal radioulnar joint and to leave room for an axial cancellous screw, which is later inserted through the most proximal hole along the shaft of the ulna. The fracture is then compressed with the insertion of long intramedullary cancellous screws and the cortical screws distal to the fracture line are then tightened to secure the plate to the ulna. The subcutaneous tissues and skin are closed in the usual manner. Finally, a removable splint is applied with the elbow flexed to 90 degrees.
Rehabilitation and Postoperative Evaluation
Active motion of the fingers and isometric contraction of the upper arm muscles is recommended as soon as pain can be tolerated. Gentle passive and active-assisted motion is initiated at 2 to 3 days postoperatively. It is recommended that patients take the arm out of the splint several times daily in order to exercise. Patients are instructed to gently flex and extend the affected elbow using the opposite hand, gradually increasing the range of motion as tolerated. Passive stretching and strengthening under occupational therapist supervision can be started at 6 weeks.
Follow ups were done and radiographic assessments were routinely performed at 4 weeks, 8 weeks, 12 weeks, 6 months, 12 months, and thereafter at a half-year or a 1-year interval. At each follow up appointment, the Mayo Elbow Performance (MEP) score and Disability of the Arm, Shoulder and Hand questionnaire (DASH) were completed. Measurements of elbow flexion, extension, and forearm rotation were done using a 1404. Hammer angle gage goniometer (Sanfeng Co. Weihai, China).
Statistic Analysis
All data were analyzed using SPSS 11.0 for Windows (SPSS Inc., Chicago, IL, USA), and descriptive summaries of the data were performed. Student's t tests were used when comparing the scores between unaffected and affected limbs. Any difference with a P value of less than 0.05 was regarded as statistically significant.