Highly extensile approach for comminuted ulna coronoid process fractures with mini-plate fixation: a case series of 31 patients

Abstract

Background: For the treatment of coronoid process fractures, medial, lateral, anterior, anteromedial, and posterior approaches have been increasingly reported; however, there is no general consensus on the method of fixation of coronal fractures. Here, we present a highly-extensile minimally invasive approach to treat coronoid process fractures using a mini-plate that can achieve anatomic reduction, stable fixation, and anterior capsular repair. Further, the study aimed to determine the complication rate of the anterior minimally invasive approach and to evaluate functional and clinical patient-reported outcomes during follow-up.

Methods: Thirty-one patients diagnosed with coronoid fractures accompanied with a "terrible triad" or posteromedial rotational instability between April 2012 and October 2018 were included in the analysis. Anatomical reduction and mini-plate fixation of coronoid fractures were performed using an anterior minimally invasive approach. Patient-reported outcomes were evaluated using the Mayo Elbow Performance Index (MEPI) score, range of motion (ROM), and the visual analog score (VAS). The time of fracture healing and complications were recorded.

Results: The mean follow-up time was 26.7 months (range, 14-60 months). The average time to radiological union was 3.6 ± 1.3 months. During the follow-up period, the average elbow extension was 6.8 ± 2.9° while the average flexion was 129.6 ± 4.6°. According to Morrey's criteria, 26 (81%) elbows achieved a normal desired ROM. At the last follow-up, the mean MEPI score was 98 ± 3.3 points. There were no instances of elbow instability, elbow joint stiffness, subluxation or dislocation, infection, blood vessel complications, or nerve palsy. Overall, 10 elbows (31%) experienced heterotopic ossification.

Conclusion: An anterior minimally invasive approach allows satisfactory fixation of coronoid fractures while reducing incision complications due to over-dissection of soft tissue injuries. In addition, this incision does not compromise the soft tissue stability of the elbow joint and allows the patient a more rapid return to rehabilitation exercises.

Keywords: Anterior minimally invasive approach; Coronoid process fractures; Highly extensile approach; Mayo elbow performance index score; Mini-plate fixation.

Fig. 1

Representative Regan-Morrey type III coronoid fracture. (a, b) Preoperative radiographs of the coronoid process fracture. (c, d) Reconstructed three-dimensional computed tomography images of the coronoid process fracture

Fig. 2

Images showing an anterior minimally invasive approach (the straight longitudinal incision over the coronoid process was made proximally from the main elbow flexion crease and extended 2 cm distally to the elbow flexion crease), and the safe space for insertion was available between the brachial artery and the median nerve

Fig. 3

Representative of intraoperative photograph of coronoid fracture. (a) Straight anterior midline incision of the elbow. (b) Dissection between the biceps brachii tendon (white cords) and medial neurovascular bundle (brachial artery, vein, or nerve plexus). (c) Brachialis is located beneath the biceps brachii. (d) The anterior capsule of the elbow was revealed after dissecting the brachialis muscle. (e) The anterior capsule was carved longitudinally, and the fracture fragments are shown. (f) The fractured fragment was fixed using a mini-plate. The entire plate can be visualized by pulling the incision on the longitudinal side

Fig. 4

Radiographs obtained during follow-up. (a, e) After 4 weeks. (b, f) After three months. (c, g) After 6 months. (d, h) 12 months after the operation

Fig. 5

There was no significant limitation in flexion, extension, pronation, and supination of the left elbow at the 1-year follow-up. a) Flexion; b) pronation, c) extension, d) supination function of the injured limb

Fig. 6

Representative “terrible triad injury of elbow”. (a, b) Preoperative radiographs. (c, d) Immediately postoperative radiographs. (e, f) After three months the operation. (g, h) The incision of the operation