Can implant removal restore mobility after fracture of the thoracolumbar segment?

Figures & data

Table 1. Characteristics of patients and fractures

Case	Sex	Age (years)	Fracture level	Fracture type
1	M	48	L1	Burst
2	M	22	L1	Burst
3	F	19	L1	Flexion-distraction
4	F	41	Th12	Burst
5	M	29	L1	Burst
6	F	27	L1	Flexion-distraction
7	F	20	L1	Flexion-distraction

Table 2. Intervertebral translations (in mm) and rotations (in degrees) in 7 patients after fracture of the thoracolumbar segment^a.

			RSA translations at fractured level (mm)			RSA rotations at fractured level (°)
Case	Fracture level	RSA measured between:	X	Y	z	X	y	z
1	L1	Th12–L2	0.4	1.8^b	1.2^b	4.7^b	0.2	0.4
2	L1	Th12–L2	0.6^b	0.4	1.7^b	2.9^b	0.1	0.6
3	L1	Th12–L1	0.6^b	0.4	0.6	1.0	0.7^b	0.1
4	Th12	Th11–L1	0.1	1.7^b	2.2^b	3.6^b	0.1	0.4
5	L1	Th12–L2	0.3	0.1	1.3^b	1.2	0.2	0.3
6	L1	Th12–L2	0.7^b	0.4	1.2^b	1.6	0.0	0.5
7	L1	Th12–L2	0.8^b	9.1^b	8.8^b	11.3^b	0.1	0.2

a Minimum significant measurement for translation is 0.5 mm (x), 0.5 mm (y), and 0.7 mm (z). Corresponding figures for rotation are 2.0˚, 0.5˚, and 0.9˚ around these axes.

b Significant mobility responses

Table 3. Intervertebral translations (in mm) and rotations (in degrees) of the adjacent segment proximal and distal to the fracture level measured in 4 patients^a

		RSA proximal to fracture level						RSA distal to fracture level
		translation (mm)			rotations (degrees)			translation (mm)			rotations (degrees)
Case	Fracture level	X	Y	Z	X	Y	Z	X	Y	Z	X	Y	Z
1^b	L1	–	–	–	–	–	–	–	–	–	–	–	–
2	L1	0.2	0.1	0.2	0.3	0.2	0.3	0.8^c	3.9^c	4.2^c	8.0^c	0.2	2.6^c
3	L1	0.1	0.2	0.1	0.3	0.1	0.1	0.1	1.4^c	0.2	2.0^c	0.1	0.0
4^b	Th12	–	–	–	–	–	–	–	–	–	–	–	–
5^b	L1	–	–	–	–	–	–	–	–	–	–	–	–
6	L1	0.2	0.1	0.1	0.2	0.1	0.1	0.6^c	0.1	0.8^c	1.0	0.3	0.1
7	L1	0.1	0.2	0.1	0.8	0.1	0.4	0.8^c	4.7^c	0.9^c	7.2^c	2.9^c	1.9^c

a Minimum significant measurement for translation is 0.5 mm (x), 0.5 mm (y), and 0.7 mm (z). Corresponding figures for rotation are 2.0˚, 0.5˚, and 0.9˚ around these axes.

b Missing values in 3 patients with short segmental instrumentation and no tantalum indicators in the adjacent segments.

c Significant mobility responses.