Spontaneous multilevel lumbar pediculolysis associated with spondylolysis: a rare case and review of the literature

Abstract

Background: Pediculolysis is bone hypertrophy and pseudoarthrosis caused by pedicle fracture and has often been combined with contralateral spondylolysis in previous reports. Multilevel pediculolysis with spondylolysis is extremely rare, and we report a case who underwent surgery. Cases of multisegment pediculolysis were reviewed to inspire the diagnosis and treatment of similar pathological phenomena.

Case presentation: A 55-year-old man suffering from low back pain and sciatica was admitted to hospital after failing conservative treatment. The imaging studies revealed bilateral pediculolysis at L3 and L4 and right spondylolysis at L5. When L2-5 internal fixation and fusion surgery were performed, the symptoms improved immediately after surgery. At the 2-year postoperative follow-up, proximal junctional failure appeared and progressively worsened.

Conclusions: Multilevel pediculolysis often requires surgical intervention, and segment instability is an important consideration in the development of surgical fusion strategies. The etiology of pediculolysis is still complex and unknown, and the spondylolysis protocol can be used as a reference for treatment. Surgeons should be cautious in surgical planning to minimize the likelihood of postoperative instrumentation failure.

Keywords: Global spinopelvic balance; Pediculolysis; Proximal junctional kyphosis; Spondylolysis; Surgical intervention.

Fig. 1

CT scan at the initial visit confirmed intact pedicles at L3 and L4 (A/E/H) and defects in the right isthmus at L5 (K, white circle). The preoperative CT revealed bilateral pediculolysis of L3 and L4, hyperplasia and sclerosis around the defect (B/F/I, red arrow), and hyperplasia and sclerosis at the right isthmus end of L5 (L, white circle). On preoperative MRI, sagittal T1- and T2-weighted images revealed hypointensity at the pedicle cleft (C/D, red arrow), cross-sections with hypointensity at the defect (G/J, red arrow), and a right isthmus with hypointensity (M, white circle)

Fig. 2

MRI median sagittal and cross-sectional scans (A/B/C) revealed L3–4 and L4–5 spinal stenosis, dural sac compression, redundant nerve roots, and nerve root sedimentation signs (+); in the sagittal view (A), the L3-4 disc indicates downward prolapsed, and the L4-5 disc indicates upward prolapsed; transverse scans reveal the upper endplate layer of L4 (B) and the lower endplate layer of L4 (C)

Fig. 3

Preoperative dynamic plain (A, B) indicates instability of L3 and L4 with spondylolisthesis, showing pediculolysis (C), and the anteroposterior plain (E) indicates the formation of scoliosis and lateral slip of L3 and L4; status immediately after L2-5 PLIF combined with TLIF surgery (D, F)

Fig. 4

At the 24-month postoperative follow-up, the sagittal and coronal CT scans (A, B) confirmed L2-3, L3-4, and L4-5 bony fusion; the sagittal image (A) showed severe degeneration of the L1-2 segment, intervertebral space and vertebral collapse, and the formation of proximal junctional kyphosis; the coronal image (B) suggested proximal degeneration and collapse; the L2 transverse scan (C, red arrow) revealed radiolucent zones around the bilateral screw tips

Fig. 5

During the follow-up period, PJA was recorded on the lateral plain preoperatively (A), immediately postoperative (B), at the 3-month follow-up (C), at the 6-month follow-up (D), at the 12-month follow-up (E), at the 18-month follow-up (F), and at the 24-month follow-up (G)

Fig. 6

MRI was performed at the last postoperative follow-up, and there were no signs of infection on sagittal (A, B, C) or transverse (D) scans

Fig. 7

At the 24-month follow-up, the full-length anteroposterior and lateral radiographs (A and B) revealed that the sagittal vertical axis (SVA) was 9.4 mm, the coronal C7PL-CSVL was 2.7 mm, and the global alignment was within the normal range. Pelvic parameters: PI: 74.4°, PT31.1°, and SS43.3°; other parameters: TK 2.6°, LL 30.4°, and PJA 52.8°