Vertebral Collapse Prevented Following Teriparatide Treatment in Postmenopausal Kümmell's Disease Patients with Severe Osteoporosis

OBJECTIVE: To compare the preventive effects of teriparatide and alendronate on the progression of vertebral body collapse in postmenopausal single‐level Kümmell's disease (KD). METHODS: From March 2013 to December 2020, the medical records for 53 postmenopausal single‐level KD patients who received conservative treatment with teriparatide (25 patients, teriparatide group) or alendronate (28 patients, alendronate group) were retrospectively reviewed. Midsagittal computed tomography (CT) images were analyzed by ImageJ to assess the intravertebral bone formation (mineralized bone) by calculating the ratio of area of intravertebral mineralized bone (AIMB) to the area of fractured vertebral body (AFVB). The changes in radiological parameters of the fractured vertebral body including kyphosis angle (KA), anterior and posterior border heights (ABH and PBH) and spinal canal diameter (SCD), bone turnover biomarkers (BTMs), and bone mineral density (BMD) were analyzed to evaluate the therapeutic effect. RESULTS: At month 12, the ratio of AIMB to AFVB was significantly greater in teriparatide group (54.28% ± 15.30%) than in alendronate group (35.57% ± 17.61%) (P < 0.001). Sagittal CT substantiated the formation of bone bridge in 16 patients in teriparatide group. No bone bridge was detected in alendronate group. The KA was significantly smaller and the ABH, PBH, and SCD was greater in teriparatide group than in alendronate group (all P < 0.001). The KA increments were significantly smaller in teriparatide group (3.98° ± 1.30°) than in alendronate group (11.43° ± 3.73°) (P < 0.001). The ABH and PBH decrement were significantly lower in teriparatide group (11.96% ± 1.93% and 2.80% ± 2.52%) than in alendronate group (37.04% ± 8.00% and 19.50% ± 8.22%) (both P < 0.001). The BTMs and BMD were significantly greater in the teriparatide group than in the alendronate group. In teriparatide group, KA increment was negatively correlated with the change in PINP (r = −0.781, P < 0.001) and the ratio of AIMB to AFVB (r = −0.592, P = 0.002) from baseline to month 12. The ABH decrement was negatively correlated with the change in PINP (r = −0.612, P = 0.001) and the ratio of AIMB to AFVB (r = −0.806, P < 0.001) from baseline to month 12. CONCLUSIONS: In postmenopausal single‐level KD patients, conservative treatment with teriparatide was better than alendronate at preventing the progressive vertebral collapse.