MR Imaging of Intra- and Periarticular Cyst-Like Lesions of the Knee Joint in Workers with Occupational Kneeling
Table 2
(a) Proportion of fluid accumulation in various bursae among 92 floor layers compared to 49 graphic designers. (b) Proportion of other cyst-like lesions among 92 floor layers compared to 49 graphic designers.
(a)
Bursae
Floor layers
Graphic designers
n
(%)
n
(%)
OR*
95% CI†
Subgastrocnemius
57
(61.9)
24
(48.9)
1.76
0.82–3.75
Unilateral
30
(52.6)
9
(37.5)
2.81
1.03–7.67
Bilateral
27
(47.4)
15
(62.5)
1.25
0.52–2.99
Semimembranosus-gastrocnemius
43
(46.7)
17
(34.7)
1.49
0.67–3.29
Unilateral
33
(76.7)
13
(76.5)
1.39
0.58–3.35
Bilateral
10
(23.3)
4
(23.5)
1.74
0.46–6.58
Prepatellar
1
(1.1)
5
(10.2)
0.16
0.02–1.55
Unilateral
1
(100)
3
(60.0)
0.33
0.03–4.18
Bilateral
0
(—)
2
(40.0)
—
—
Superficial infrapatellar
4
(4.3)
2
(4.1)
0.90
0.14–5.75
Unilateral
4
(100)
1
(50.0)
1.78
0.17–19.21
Bilateral
0
(—)
1
(50.0)
—
—
Deep infrapatellar
10
(10.8)
2
(4.1)
3.53
0.64–19.65
Unilateral
9
(90.0)
2
(100)
3.22
0.56–18.32
Bilateral
1
(10.0)
0
(—)
—
—
Anserine
5
(5.4)
0
(—)
—
—
Unilateral
5
(100)
0
(—)
—
—
Bilateral
0
(—)
0
(—)
—
—
Bursae, others‡
7
(7.6)
0
(—)
—
—
Unilateral
5
(71.4)
0
(—)
—
—
Bilateral
2
(28.6)
0
(—)
—
—
(b)
Other cyst-like lesions
Floor layers
Graphic designers
n
(%)
n
(%)
OR*
95% CI†
Popliteus
Tendon recesses
53
(51.0)
22
(34.7)
2.17
0.99–4.77
Unilateral
24
(57.4)
19
(88.2)
1.14
0.48–2.73
Bilateral
29
(42.6)
3
(11.8)
8.89
2.21–35.74
Muscle cysts
13
(14.1)
2
(4.1)
3.83
0.78–18.89
Unilateral
12
(92.3)
2
(100)
3.40
0.68–17.06
Bilateral
1
(7.7)
0
(—)
—
—
Extracapsular synovial cysts§
9
(9.8)
0
(—)
—
—
Unilateral
6
(66.7)
0
(—)
—
—
Bilateral
3
(33.3)
0
(—)
—
—
Insertional cysts
ACL¶
10
(10.8)
7
(14.3)
1.05
0.33–3.39
Unilateral
8
(80.0)
7
(100)
0.91
0.27–3.07
Bilateral
2
(20.0)
0
(—)
—
—
PC
4
(4.3)
0
(—)
—
—
Unilateral
3
(75.0)
0
(—)
—
—
Bilateral
1
(25.0)
0
(—)
—
—
Hoffa fat pad recesses
18
(18.5)
5
(10.2)
1.80
0.59–5.48
Unilateral
11
(58.8)
5
(100)
1.04
0.31–3.44
Bilateral
7
(41.2)
0
(—)
—
—
Parameniscal cysts
Medial
12
(13.0)
2
(4.1)
4.28
0.80–22.87
Unilateral
10
(83.3)
2
(100)
3.24
0.59–17.69
Bilateral
2
(16.7)
0
(—)
—
—
Lateral
3
(3.2)
2
(4.1)
1.14
0.17–7.87
Unilateral
3
(100)
1
(50.0)
2.37
0.21–26.43
Bilateral
0
(—)
1
(50.0)
—
—
*Odds ratio calculated relative to graphic designers. Adjusted for age, body mass index, knee injuries, and knee-straining sports. †Confidence interval. ‡Medial and lateral collateral ligament, biceps femoris, semimembranosus-gracilis. §From capsular defects of the dorsal femoral condyles. ¶Anterior cruciate ligament. osterior cruciate ligament.
