Surgical treatment of lateral clavicle fractures associated with complete coracoclavicular ligament disruption: Clinico-radiological outcomes of acromioclavicular joint sparing and spanning implants

Abstract

Purpose: Distal clavicle fracture associated with complete coracoclavicular ligament disruption represents an unstable injury, and osteosynthesis is recommended. This study was performed (1) to retrospectively analyse the clinico-radiological outcomes of two internal fixation techniques, and (2) to identify and analyse radiographic fracture patterns of fracture that are associated with this injury.

Materials and methods: A total of 15 patients underwent osteosynthesis with either (1) acromioclavicular joint-spanning implants (Group 1, Hook plate device, n = 10) or (2) joint-sparing implants (Group 2, distal radius plate, n = 5); these were reviewed at a mean period of 26.1 months (12 to 40 months). Clinical outcomes were measured using Constant Score (CS), Simple Shoulder Test (SST), and Walch ACJ score (WS). Radiographs and ultrasonography were used to assess the glenohumeral and acromioclavicular joints, and the subacromial space. Preoperative radiographs were analyzed for assessment of fracture lines to identify radiographic patterns. Statistical analysis of the data was performed to determine any significant differences between the two groups.

Results: The overall clinical outcome was satisfactory (CS 80.8, SST 11.3, WS 17.6) and a high union rate (93.3%) was observed. Radiographic complications (acromioclavicular degeneration and subluxation, hook migration, abnormal ossification) did not negatively influence the final clinical outcomes. Four distinct radiographic fracture patterns were observed. A statistically significant difference ( P < 0.05) was observed in the reoperation rates between the two groups.

Conclusions: Internal fixation of this fracture pattern is associated with a high union rate and favorable clinical outcomes with both techniques. A combination of distal radius plate and ligament reconstruction device resulted in stable fixation and significantly lower reoperation rates, and should be used when fracture geometry permits (Types 1 and 2).

Design: Retrospective review of a consecutive clinical case series.

Setting: Level 1 academic trauma service, Public Hospital.

Keywords: Acromioclavicular joint; comminution; distal clavicle fracture; fracture patterns; hook plate; locking radius plate; ultrasound.

Figure 1a

Surgical treatment of an unstable distal clavicle fracture with a joint-spanning implant (Group 1). (Hk: Hook plate, CL: Clavicle, M: Medial fragment, L: Lateral fragment, arrow: Fracture line, Ac: Acromion, H: Humeral head, Co: Coracoid process)

Figure 1b

Surgical treatment of an unstable distal clavicle fracture with a joint-sparing implant and coracoclavicular ligament reconstruction using endobutton device (Group 2). (RP: Locking distal radius plate, arrow: Acromioclavicular joint, Ac: Acromion, CL: Clavicle, En: Endobutton, H: Humeral head)

Figure 2

Radiographic outcomes of surgical treatment at follow-up are shown. (a) Acromioclavicular joint degeneration (arrow). (b) Acromioclavicular joint subluxation (arrows), (c) Hook migration and osteolysis of acromial undersurface (arrow), (d) Peri-coracoid ossification (arrows). (Ac: acromion, CL: clavicle, Co: coracoid, P: plate, An: suture anchor, G: glenoid, H: humeral head, Hk: hook plate, AHI: acromiohumeral interval)

Figure 3

Ultrasonographic outcomes of surgical treatment at follow-up are shown. (a) Partial articular-surface supraspinatus tendon avulsion (Black arrows) (b) Screw penetration into the acromioclavicular joint (arrows). (GT: Greater tuberosity, H: Humeral head, SS: Supraspinatus, Ac: Acromion, CL: Clavicle, asterix: Acromioclavicular joint)

Figure 4

Radiographic fracture patterns: (a) Type 1, (b) Type 2, (c) Type 3, and (d) Type 4. (Ac: Acromion, CL: Clavicle, Co: Coracoid, G: Glenoid, H: Humeral head, arrows: Fracture lines)