The Functional Outcome of Open Reduction and Internal Fixation of Unstable Floating Shoulder Injuries: A Prospective Study with Good Short-Term and Medium-Term Outcome

Abstract

Introduction: The term "superior shoulder suspension complex (SSSC)" coined by Goss is a bone and soft tissue stable ring made up of clavicular-acromioclavicular strut, the three-process scapular body and the clavicular-coracoclavicular ligamentous-coracoid (C-4) linkage. Disruption at any one site of the SSSC complex makes the other site unstable in a vicious cycle altering the functional anatomy and muscular forces resulting in a "floating shoulder injury" (FSI). The purpose of this study is to evaluate the functional outcome after open reduction and internal fixation of both clavicle and scapula in FSI using Herscovici and American shoulder and Elbow score (ASES) scores.

Materials and methods: This is a prospective study conducted at level 1 trauma care center in India from May 2019 to May 2023 in 18 cases of unstable FSI. All the cases were followed up post-operatively for a period of 18 months.

Results: All the injuries were high energy motor vehicular accidents. Fracture union was seen in all cases with mean period of 13.55 weeks for clavicle and 8.5 weeks for scapula on plain radiographs. 72.22% of the patients had an excellent to good functional outcome assessed by Herscovici scoring system and 61% had an ASES score between 50 and 100. No patient had any adverse complication which precluded their return to their daily activities.

Conclusion: Early open reduction and internal fixation of significantly displaced unstable FSIs allows early rehabilitation and better functional outcome.

Keywords: Floating shoulder injury; clavicle fracture; spinal pillar fractures; surgical fixation.

Figure 1

The glenopolar angle (GPA) measured on 3D reconstruction computed tomography. GPA is the angle between two lines; line 1 extending from the superior glenoid pole to inferior glenoid pole and line 2 connecting the superior glenoid pole to the inferior most pole of inferior pole of scapula.

Figure 2

Medialization/lateralization displacement as measured on 3D computed tomography scan. It is measured by determining the distance between the vertical planes (represented by two blue vertical arrows) drawn at the lateral most edge of both scapular fragments.

Figure 3

Post-operative well-healed surgical site showing lateral column approach to scapula glenoid and lateral pillar.

Figure 4

Post-operative radiograph showing well fixed scapula and clavicle with restored biomechanics of the shoulder at 3-month follow-up.