Comparing Thoracic Extensive Laminoplasty (TELP) and Laminectomy in Treating Severe Thoracic Ligamentum Flavum Ossification: A Proposed Novel Technique and Case-Control Study

Abstract

Objective: (1) To propose a novel technique named thoracic extensive laminoplasty (TELP) in curing severe thoracic ligamentum flavum ossification (STOLF) and (2) to compare outcomes between TELP and laminectomy in curing STOLF.

Methods: Cases with fused or tuberous STOLF (Sato classification) treated from Jan 2015 to Jan 2017 were reviewed and divided into the TELP group (G1) and laminectomy group (G2) according to their surgical management. Data on demographics, complications, pre- and postoperative symptoms, residual spinal canal area (RSCA-1), residual spinal cord area (RSCA-2), modified Japanese Orthopedic Association score (mJOA), and health-related quality of life (HRQOL, based on the SF-36) were collected.

Results: Fifty-nine G1 and sixty-two G2 patients were enrolled. No significant differences in demographic data or preoperative data of RSCA-1, RSCA-2, mJOA, or HRQOL were observed between the two groups (p > 0.05). Patients in G1 and G2 showed similar postoperative improvements in RSCA-1 and RSCA-2 at the final follow-up (p > 0.05). However, patients in G1 showed higher postoperative improvements in mJOA (OR = 2.706, 95% CI: 1.279~5.727, p = 0.008) at the final follow-up. Patients in G1 also showed higher postoperative improvements in HRQOL than patients in G2 (p < 0.05) at the final follow-up, and patients with more severe STOLF presented with better improvements in HRQOL in G1 (p < 0.05). Dural laceration and cerebrospinal fluid leakage were observed in seven G2 patients, and no complications were found in G1 patients after surgery.

Conclusion: TELP is a novel, effective, and safer surgical technique in treating STOLF and could be a substitute for traditional laminectomy.

Figure 1

Illustration of residual spinal canal area (RSCA-1) and residual spinal cord area (RSCA-2). (a) The area of the normal spinal canal. (b) The area of the narrow spinal canal. RSCA-1 or RSCA-2: S2/S1; RSCA-1 was evaluated by CT; and RSCA-2 was evaluated by MRI.

Figure 2

Illustration of the procedures of thoracic extensive laminoplasty (TELP) in a coronal view. (a) The thoracic spine with ossified ligamentum flavum (OLF in brown color). (b) Excision of the spinous process and portion of the lamina (not shown in the picture). (c) Bilateral grooves were made by grinding with a drill, and the lamina was isolated bilaterally. (d, e) Lifting the lamina (OLF in brown color) by towel forceps. (f) Fixation by arch plates and fusion with corticocancellous bone (not shown in the picture). (g) Intraoperative view of the TELP.

Figure 3

Illustration of the procedures of thoracic extensive laminoplasty (TELP) in a cross-section view. (a) The level of vertebra with TOLF. (b) Excision of the spinous process and portion of the lamina (not shown in the picture). (c) Bilateral grooves were made by grinding with a drill, and the lamina was isolated bilaterally. (d) Lifting the lamina by towel forceps. (e) Fixation by arch plates and fusion with corticocancellous bone (not shown in the picture).

Figure 4

A 45-years old patient with STOLF from T3 to T5 levels who received TELP. (a) Preoperative CT. (b) Preoperative MRI. (c, d) Postoperative standing anteroposterior X-ray at final follow-up. (e) Postoperative MRI at final follow-up. (f) Postoperative CT at final follow-up. (g) Postoperative three-dimensional CT reconstruction at final follow-up.

Figure 5

A 49-year-old patient with STOLF from T9 to T11 levels who received laminectomy. (a, b) Preoperative standing anteroposterior X-ray. (c) Preoperative CT. (d) Preoperative MRI. (e, f) Postoperative standing anteroposterior X-ray at final follow-up. (g, h) Postoperative MRI at final follow-up.