The OF classification and OF indication score of osteoporotic thoracolumbar fracture, clinical treatment and complications: A prospective multicenter study

Objectives Osteoporotic fractures of the spine (OF) are a rising health issue. Therefore, the research group ‘OF’ (AG-OF) of the spine section of the German Society for Orthopedics and Trauma (DGOU) has developed OF-Classification and OF-Score. The Score takes into account OF-Classification, bone density, sintering, pain, neurology, mobilization and health status. OF-Scores < 6 recommends non-operative treatment. Operative treatment is recommended with OF-Scores >6. No recommendation is done for score = 6. The value of this score is not evaluated yet.

Methods This prospective, multicenter longitudinal study evaluates the OF-Classification and OF-Score. The study was initiated in 2017 with a total of 11 hospitals involved. Inclusion criteria was an OF of thoracolumbar spine in an inpatient setting. Exclusion criteria was spondylodiscitis and tumor disease. Age, gender, trauma, bone density, OF-Classification, OF-Score, status of antiosteoporotic therapy (aoTh), procedure and complications were recorded at the day of inpatient acquisition, day of treatment decision (dtd) and discharge.

Results and Conclusion A total number of 216 patients were included (51 male, 165 femal) with a mean age of 73 ±9 years (50-97). 143 (66%) patients had demonstrable trauma, in 3 (1%) cases this was unknown and 70 (32%) showed a spontaneous

fracture. The OF classification was distributed as follows: OF1: 3 (1%), OF2: 61 (28%), OF3: 83 (38%), OF4: 56 (26%) and OF5: 11

(5%).

During hospitalization, the number of patients receiving aoTh increased significantly at each time point of exposure (admission: 33%, dtd: 63%, discharge: 75%, p<0.01). The medicaments were usually administered in combination. Bisphosphonates increased from 27% to 41% and Vit. D3 from 58% to 91%.

88 patients (17 male, 71 femal), were treated conservatively and 114 surgically (29m, 85f). 68% (N 128) were treated according to the OF-score and 32% (N 59) were treated different to the OF-score. 14 patients (7%) had an intermediate OF-Scores of 6. 11 of them were treated surgically, 3 conservatively.

During the inpatient stay we observed a sig. reduction of the OF-Score (p< 0,001). No sig. difference in OF-Score reduction could be detected following the 2 interventions (p=0.302).

85% of the surgeries were done percutaneously. Hybrid stabilization was performed on 49 patients (65%). On 65 patients (81%) a screw augmentation was performed. 4 complications that required revision arose in OF typ 4 and 5.

The OF-Classification follows a Gaussian distribution curve. The significant increase in aoTh during inpatient stay is pleasing. On the other hand there seems to be a lack of awareness of osteoporosis in this population because of the low rates of aoTh at admission. The majority was treated OF-conform. The surgical procedures were done predominantly percutanously. Thereby hybrid stabilization was most common. Pedicle screws were augmented in the huge majority. In terms of complications attention must be given to the OF -Typ 4 and 5.

Stichwörter spine, osteoporotic fracture, Classification, Score

Publication History

Article published online:
15 October 2020