OBJECTIVES

This study aims to describe the patient presentation in Japan and their post-operative burden for spinal fusion surgery with pedicle screws, and define subgroup differences such as osteoporosis or multi-level fusions.

METHODS

Patients ≥18 years old who had spine fusion procedures with standard pedicle screws between 2010-2017 were identified using the Medical Data Vision Co.,Ltd. claim database. Osteoporotic patients were identified with diagnostic code M80, M81 or/and receipt of osteoporotic medication. Additional fixation instruments of interest were cross-link, wires, hydroxyapatite coating stick, calcium phosphate bone/cement. Baseline characteristics, complications, re-admissions, spine related re-operations, LOS and healthcare expenditures were extracted. Descriptive statistics were calculated to assess these endpoints.

RESULTS

There were 22,932 patients meeting the study criteria (M: 51.2%, mean age±SD: 67.3±13.3 years). Osteoporotic patients represented 23% (60% increase since 2010), were older (73.8±8.58) and mainly female (76.6%). Multi-level fusion cases accounted for 26.84% cases.

Additional fixation instruments were required in 12.8% patients, with wires generally preferred.

For multi- vs. single levels, a statistically significant higher rate was observed for mechanical failures (0.9% vs 0.7%, p=0.044), reoperations (8.2% vs. 6.2%, p<0.0001), readmissions (30.7% vs 25.0%, p<0.0001), at 24-month post-surgery. The median LOS [IQ range] was also higher (27.0 days [18.0; 43.0] vs. 21.0 [16.0; 30.0], p<0.0001).

Results for osteoporotic vs non-osteoporotic patients showed respectively 1.2% vs. 0.6% p<0.001, 9.0% vs. 6.1% p<0.001, 30.7% vs. 25.3% p<0.001 and 26.0 [19.0; 42.0] vs 21.0 [16.0; 31.0]; thus posing a higher burden on the total healthcare expenditures (median in million JPY: 3.44 [2.59; 4.77] vs. 2.70 [2.20; 3.62]).

CONCLUSIONS

In this study, patients with osteoporosis or multi-level spinal fusion had higher rates of post-operative complications, reoperation, and readmission than those without these conditions; these factors also were associated with longer LOS and higher healthcare expenditures. This underscores the need for innovation to improve spinal fixation among high-risk subgroups.