The patient was a 75-year-old man without any relevant medical history. He presented with low back pain and bilateral buttock pain (numeric rating scale [NRS] score of 4 points; wherein 0 to 10 points denoted no pain to extreme pain, respectively), which had persisted since July 2021. Magnetic resonance imaging (MRI) at another hospital revealed an L4-compression fracture (Fig. 1A) followed by sudden weakness and pain in his right leg and L3-L4 dermatome (NRS 7 points) after 6 weeks; subsequently, he presented at our emergency department. The patient had a walking disability and grade IV motor weakness in his right hip, which was otherwise intact. He was admitted to our hospital after plain radiography and contrast-enhanced computed tomography (CT) scans showed a mass-like lesion in the left upper lobe (LUL) (Fig. 1B). The following tumor markers showed elevated levels: carcinoembryonic antigen, 112 ng/mL; carbohydrate antigen 19-9, 53.9 U/mL; and cytokeratin fragment 21-1, 10.6 ng/mL. Contrast-enhanced MRI scanning performed the day after admission showed extraosseous extension, spinal canal stenosis, and a pathologic compression fracture (Fig. 1C) by enhancement at the L4 level. CT-guided bone biopsy at the L4 level revealed a metastatic lesion of non-small cell lung carcinoma (NSCLC). Positron emission tomography-CT scan showed uptake in the LUL, L4 body, and T1 body (Fig. 1D). CT-guided needle aspiration biopsy of the LUL and subsequent histopathologic evaluation confirmed the lesion as a grade IV, B-type Raf kinase-negative, and epidermal growth factor receptor-negative NSCLC. Considering the patient’s lung cancer stage and poor general condition (Eastern Cooperative Oncology Group grade 3), palliative, L4-limited decompression was performed using the posterior approach under general anesthesia. His leg pain reduced (NRS 3 points), and he resumed walker-assisted ambulation. His cancer treatment was continued with once-daily radiotherapy (600 Gy each time) sessions. On the day after the first radiation therapy session, worsening leg pain (NRS 6 points) occurred, which was visualized as an exacerbation of L4 metastasis with severe stenosis (Fig. 2A) on MRI scans. Chemotherapy with Alimta (810 mg) and cisplatin (121.5 mg) was initiated while contemplating the need for additional surgery.

Six days later, which was 2 days after the embolization of L3-L4 spinal arteries, L4-spondylectomy and L3-S1 posterior screw fixation were performed using a customized 3D-printed mesh cage (Fig. 2B) for efficient weight-bearing and lordotic-curve preservation. The leg pain improved (NRS 3 points), and the patient resumed walker ambulation. The second chemotherapy treatment was performed 2 weeks later, followed by additional radiotherapy performed daily on the T1-T2 spine (500 Gy each time). The patient underwent the third chemotherapy session three weeks later (December 15), and his leg pain improved further (NRS 2 points). He remains under general hospital care (February 2022) to drain wound fluid, manage leukopenia, and undergo further chemotherapy.

The patient was a 63-year-old woman without any documented medical history. Approximately 13 years ago, she slipped and experienced aggravating back pain 3 months later. Subsequently, T11-L1 compression fracture was diagnosed and managed with conservative care, and her pain subsided. Her back pain resurfaced 6 months before presentation, when she lifted a heavy object and had numbness in both soles of the feet and a cold sensation in the legs, resulting in gait disturbance. She visited the emergency room and received conservative care through the outpatient clinic. No motor deficit was observed, but hypoesthesia was present in both feet. No abnormal deep tendon reflex was observed. Plain radiography (Fig. 3A), CT (Fig. 4A, B), and MRI (Fig. 3B-D) findings revealed severe compression fracture at the T11-L1 level that caused severe kyphosis and stenosis in the thoracolumbar junction. Her symptoms worsened and she was admitted for surgical repair of the spinal deformity. After screw insertion from T9 to L2, total laminectomy of T11 was performed with VCR (grade V osteotomy) following the pedicles. In the empty space after VCR, a 3D-printed titanium mesh cage (Fig. 4C) was inserted. Rods were connected using a domino and a T8 hook, and the surgery was completed without changes in the motor evoked potentials. There was severe postoperative pain, which required pain control medications followed by a slow walking ability. Postoperative plain radiography (Fig. 4D, E) showed a stable cage position. She was discharged on postoperative day 15. During follow-up visits at 1, 4, and 7 months, she showed stability while walking without evidence of dislocations or mechanical failure on her X-rays. Written informed consent was obtained from the patients for the publication of the case report and accompanying images. The study adhered to the Declaration of Helsinki and was approved by the appropriate Institutional Review Board (redacted for peer review).