Arthroscopic anterior shoulder bone-block stabilisation using distal clavicle autograft: A case series of 41 patients.

BACKGROUND: Glenoid bone loss is a significant risk factor for recurrent shoulder instability following surgical stabilisation. Coracoid transfer (Latarjet) remains the gold standard in treating anterior shoulder instability associated with bone loss. Complication rates of up to 25% have however been reported with the Latarjet procedure. Free bone block transfer procedures may potentially avoid some of these complications by providing a more anatomical glenoid reconstruction with equivalent rates of recurrent instability to the Latarjet procedure having previously been reported. Uncertainty remains however regarding the optimal graft of choice for this procedure. We present the largest reported clinical series of performing arthroscopic anterior bone block stabilisation using distal clavicle autograft (DCA).

METHODS: We reviewed the data of 41 consecutive patients who underwent arthroscopic bone block anterior stabilisation using DCA between November 2020 and November 2023. All procedures were performed by one of two surgeons at two centres utilising a standardised operative technique. Indications for the procedure included failed soft tissue stabilisation, glenoid bone loss > 15% or bipolar bone loss with an engaging Hill-Sachs lesion. Pre and post-operative data collection included patient demographics, percentage glenoid bone loss, size of Hill-Sachs lesion, previous surgery, Oxford Shoulder Instability Scores (OSIS), post-operative complications and recurrent instability. Post-operative computed tomography (CT) scans were performed between 6-21 weeks following surgery.

RESULTS: 85% of patients in the study were male with a mean age of 30. Mean pre-operative glenoid bone loss was 14% and thirty-seven (90%) of patients had bipolar bone loss. Fifteen patients (37%) were revision procedures for recurrent instability. 33 patients (80.5%) had OSIS recorded pre and post-operatively with the last OSIS being recorded over 24 months post-operatively in 25 patients (61.0%). The mean follow-up time was 37 months (range 3-67). The mean increase in OSIS was 20 points with the difference between pre and post-operative scores reaching statistical significance (p<0.0001). This improvement was demonstrated to be maintained in the subgroup of 25 patients with > 24 months follow-up data. 39 (95.1%) patients had a post-operative CT scan demonstrating full or partial union in 38 (92.7%) patients. Donor site morbidity was not reported by any patient. 1 patient (2.4%) had recurrent instability post-operatively during the study period.

CONCLUSION: Our results demonstrate that DCA arthroscopic bone block anterior stabilisation is a safe and effective technique associated with good radiological and patient outcomes and low rates of recurrent instability comparable to coracoid transfer in the short-term.