Early clinical outcomes of standard and 3D-planned pre-bent hook plates versus suture-button fixation for acute Rockwood IIIB-V acromioclavicular dislocation with a Bigliani type II acromion: a retrospective cohort study.

BACKGROUND

Surgical management of acute high-grade (Rockwood IIIB–V) acromioclavicular joint dislocation (ACD) remains controversial. Standard clavicular hook plating (CHP) provides reliable reduction, but subacromial irritation/osteolysis and routine plate removal remain important concerns, particularly in patients with a Bigliani type II acromion. Three-dimensional (3D) planning may improve implant fit, whereas suture-button (SB) fixation represents a minimally invasive alternative. We compared Standard CHP, 3D-planned pre-bent CHP (3D-CHP), and SB fixation with respect to early recovery, subacromial morbidity, and secondary procedure burden.

METHODS

We retrospectively reviewed 125 patients with acute high-grade ACD and a Bigliani type II acromion treated at a single center (CHP, n = 49; 3D-CHP, n = 33; SB, n = 43). The primary endpoint was VAS pain score at 3 months, and the key secondary endpoint was Constant–Murley Score (CMS) at 3 months. Additional outcomes included shoulder range of motion, coracoclavicular distance (CCD) and related radiographic events, subacromial erosion, complications, and secondary procedures within 24 months.

RESULTS

Baseline characteristics were broadly comparable across groups. At 3 months, 3D-CHP and SB showed lower VAS pain scores and higher CMS than Standard CHP (both P < 0.05). By 24 months, pain, function, and radiographic maintenance were comparable across groups (all P > 0.05). Subacromial erosion was less frequent after 3D-CHP and absent after SB than after Standard CHP (P < 0.001). Planned plate removal accounted for most secondary procedures in the hook-plate groups, whereas unplanned reoperation was rare and did not differ significantly among groups (P = 0.144). SB subgroup outcomes were similar between Rockwood IIIB and pooled IV/V injuries.

CONCLUSIONS

All three approaches achieved comparable 24-month functional and radiographic outcomes. The main between-technique differences appeared to concern early postoperative recovery, hook-related subacromial morbidity, and implant-related secondary procedure burden. Standard CHP provided reliable fixation, 3D-CHP may represent a refinement of hook-plate fixation aimed at improving implant–acromion conformity, and SB offered a less invasive alternative that avoided routine implant removal. CLINICAL TRIAL REGISTRATION: Not applicable.