Gongji classification and treatment strategies for lateral clavicle fractures / 中华骨科杂志

ABSTRACT

Objective:To establish a new classification of lateral clavicle fractures and to evaluate its clinical value.Methods:The data of 67 patients with lateral clavicle fractures admitted from January 2016 to December 2020 were included. Thirty-seven cases were from Shanghai First People's Hospital, including 22 males and 15 females, with an average age of 49.1 years (22-78 years). Thirty cases were from the Second Upper Limb Ward of Tianjin Hospital of Tianjin, including 20 males and 10 females, with an average age of 47.6 years (19-76 years). The ligament injury was determined by measuring the coracoclavicular space on Zanca view X-ray and the distance between the fracture fragment on the inferior surface of the 3D-CT and the distal end of the clavicle. All patients were classified according to the new classification (based on the measurement on Zanca view X-ray and 3D-CT reconstruction, the relationship between the fracture and the coracoclavicular ligament footprint, coracoclavicular ligament injury, the injury of the acromioclavicular joint and the stability of the fracture), conservative treatment is preferable for stable fractures, and surgical treatment for unstable fractures. Three experienced orthopaedic surgeons and three radiologists independently observed the imaging data of 67 patients with distal clavicle fractures, determined the fracture type according to the new classification, and randomly reclassified after 4 weeks interval. Finally, 15 cases were randomly selected for internal control (2 junior orthopedic physicians), and the ICC value was used to assess the reliability. Results:The lateral clavicle fractures were divided into 5 types according to the Gongji classification. Type 1 isolated conical tubercle avulsion fracture, and the fracture line is located medial to the coracoid process; Type 2 complete involvement of the trapezoid & conical ligament at the clavicle insertion, and the fracture line extends to the middle of the clavicle, mean while the acromioclavicular joint is intact; Type 3 fracture fragments on the inferior surface involving the trapezoidal/conical ligament, respectively; Type 4 rupture of the conical ligament, and avulsion fracture of the trapezoid ligament; Type 5 conical ligament intact, and avulsion fracture of clavicle insertion of the trapezoid ligament. There were 18 cases of type 1, 4 cases of type 2, 8 cases of type 3, 32 cases of type 4, and 5 cases of type 5. The inter-observer and intra-observer agreement of all included cases was good (inter-group first ICC=0.764, second ICC=0.778; intra-group shoulder specialist ICC=0.782, radiologist ICC=0.750, internal control ICC=0.793). Types 1 and 2 fractures were fixed with anatomical plate and coracoid anchor. Type 3 and 4 fractures were fixed with clavicle hook plate and coracoid anchor. And type 5 underwent conservative treatment. At the last follow-up, all patients had no obvious shoulder joint instability and pain, and no internal fixation failure or fixation breakage was found. Conclusion:The Gongji classification has moderate reliability between observers and intra-observers, and the Gongji distal clavicle fracture classification has a good significance for evaluating the stability of the fracture and guiding the selection of the treatment.