Intradiscal Pressure Changes during Manual Cervical Distraction: A Cadaveric Study
Table 2
Summary of pressure decreases (kPa) for all DCs.
Contact location
DC1,
DC2,
DC3,
DC4,
Mean
SD
Mean
SD
Mean
SD
Mean
SD
Neutral traction
C5
C4-C5
76.8
67.6
118.6
138.3
64.8
—
52.0
70.6
C5-C6
75.3
52.2
53.0
44.6
50.5
—
100.1
31.4
C6-C7
67.7
47.6
47.2
23.1
27.9
—
83.2
5.1
C7-T1
39.1
47.8
0.1
66.9
16.5
—
62.7
2.7
C6
C4-C5
70.5
68.7
118.5
103.5
74.9
32.3
104.0
90.8
C5-C6
63.4
51.4
44.9
25.1
19.2
27.1
81.6
79.1
C6-C7
63.7
38.9
47.2
49.9
30.7
17.0
93.7
4.6
C7-T1
11.2
64.5
−17.5
78.9
−30.2
72.1
−0.9
95.7
Fixed flexion and traction
C5
C4-C5
46.5
52.4
91.6
131.3
13.3
—
4.7
9.5
C5-C6
41.9
33.3
31.9
48.6
27.3
—
48.7
44.5
C6-C7
54.9
34.8
35.7
36.6
8.9
—
51.2
61.0
C7-T1
10.5
53.4
14.6
42.7
10.7
—
69.2
47.4
C6
C4-C5
54.8
65.8
97.0
102.5
28.7
12.1
2.3
65.1
C5-C6
48.7
38.9
20.0
23.1
10.2
14.5
47.6
41.5
C6-C7
59.8
34.9
12.8
76.6
23.3
19.1
42.0
23.7
C7-T1
−7.0
69.0
−31.8
63.8
−23.4
56.2
−22.5
51.6
Moving flexion and traction
C5
C4-C5
82.8
56.1
112.5
150.2
92.8
—
36.2
60.8
C5-C6
68.1
65.1
41.4
46.8
75.2
—
91.2
21.5
C6-C7
84.9
64.5
38.9
38.1
37.3
—
79.9
25.8
C7-T1
41.5
55.3
20.4
55.9
35.7
—
57.6
27.6
C6
C4-C5
86.2
49.3
168.7
211.1
114.7
47.4
118.7
116.9
C5-C6
65.8
55.5
55.1
48.7
31.8
45.0
87.0
82.8
C6-C7
94.3
64.0
33.0
16.1
64.0
56.7
70.4
53.0
C7-T1
26.4
52.2
−58.1
70.9
−21.5
62.7
−19.2
63.2
Generalized traction
C4-C5
43.0
72.5
118.6
143.9
94.9
1.9
51.0
55.4
C5-C6
58.6
67.9
85.7
106.3
48.6
68.8
98.4
88.6
C6-C7
53.1
33.7
60.5
59.0
30.9
16.1
146.1
30.8
C7-T1
−29.4
80.9
−15.3
68.0
−16.6
13.9
—
—
Generalized traction fixed flexion
C4-C5
66.0
83.3
51.7
77.0
34.2
31.4
23.0
46.3
C5-C6
38.6
59.8
45.1
70.1
15.2
21.7
50.6
49.3
C6-C7
73.6
82.5
67.1
68.9
69.8
81.1
103.2
60.9
C7-T1
−23.7
50.6
0.2
68.0
−8.1
6.3
11.9
46.1
Note that, for DC3, one of the specimens he tested did not have C5 as a contact location; therefore, no SD could be calculated, negative numbers represent increases in IDP.
