Comparison of Posterior Atlantoaxial Intra-articular Cage Fusion Through Intermuscular Versus Open Approach for Atlantoaxial Dislocation

BACKGROUND AND OBJECTIVE: The posterior atlantoaxial intra-articular cage fusion through intermuscular approach (AICF-IA) technique can largely preserve the integrity of the paravertebral muscles. However, few studies have analyzed the differences in effect of treatment between this minimally invasive surgery and the conventional posterior AICF through open approach (AICF-OA) technique. The objective of this study was to analyze the differences between the AICF-IA technique and the AICF-OA technique for atlantoaxial dislocation (AAD). METHODS: The patients comprised 2 matched groups: 32 patients treated with the posterior AICF-IA technique and 32 patients treated with the posterior AICF-OA technique. The differences between the 2 groups in the operation time, perioperative blood loss, postoperative drainage volume, postoperative pain, supplementary use of narcotics, postoperative length of hospital stay, bone fusion time, the Japanese Orthopaedic Association scores and reduction of AAD (determined based on radiographic parameter: atlantodental interval) were analyzed. RESULTS: Successful reduction and fusion were achieved in all patients in this study. There were no significant differences between the 2 groups in bone fusion time, Japanese Orthopaedic Association scores, and reduction of AAD. Compared with the open approach group, the intermuscular approach group had a longer operative time (115.4 ± 22.6 minutes vs 91.1 ± 21.4 minutes, P < .05) but less intraoperative blood loss (80.2 ± 32.9 mL vs 299.7 ± 89.0 mL, P < .05), less postoperative drainage volume (41.3 ± 6.2 mL vs 135.2 ± 40.8 mL, P < .05), lower short-term postoperative pain, less need for supplementary narcotics (18.8% vs 87.5%, P < .05), and a shorter postoperative hospital stay (4.1 ± 1.1 days vs 7.1 ± 1.4 days, P < .05). CONCLUSION: Compared with the open approach, the posterior AICF-IA technique was associated with reduced intraoperative blood loss and improved immediate postoperative outcomes, while achieving comparable core efficacy outcomes. The minimally invasive surgery can facilitate rapid patient recovery.