Table 2

 Characteristics and selected results of studies examining occupational kneeling and risk of knee injury (males only)

Study periodPopulationExposureOutcome*OR(95% CI)
*K&L and Ahlbäck refer to classifications of radiographic appearance of arthrosis of the knee.
†Results given are for male and female subjects combined.
Strong evidence
Felson et al441983–85Cohort (US). Sample of population already taking part in heart study (n = 569)Assessment of physical demand and knee bending requirement of occupationsK&L⩾2Bending and light work1.07(0.53 to 2.17)
Bending and heavy work2.22(1.38 to 3.58)
Kivimäki et al46Not specifiedCase control (Finland). Cases: carpet and floor layers (n = 168). Controls: painters (n = 146)Carpet/floor layers v paintersOsteophytes and knee painFloor layers1.40(1.10 to 1.70)
Cooper et al48Not specifiedCase control (UK). Cases: knee pain and radiographic OA (n = 109). Controls: no knee pain or OA (n = 218)Time spent squatting or kneeling in longest held job before symptom onsetK&L⩾3Squatting3.70(0.80 to 16.60)
Knee painKneeling1.80(0.60 to 5.70)
Sandmark et al511991–93Case control (Sweden). Cases: knee replacement (n = 325). Controls: population register (n = 264)Frequency of squatting/knee bends during working day. Time spent kneelingKnee replacementSquatting/knee bending2.90(1.70 to 4.90)
Kneeling2.10(1.40 to 3.30)
Coggon et al52Not specifiedCase control (UK). Cases: waiting list for knee surgery (n = 205). GP controls (n = 205)Time spent kneeling or squatting in all jobs held for one year or moreAwaiting knee surgeryKneeling1.70(1.00 to 3.00)
Squatting2.20(1.00 to 4.90)
Moderate evidence
Sharrard & Liddell111958–60Case control (UK). Cases: meniscectomy patients (n = 957). Controls: appendicectomy patients (n = 1075)Miners v non-minersMeniscectomy<25 years2.00
25–54 years4.00
⩾55 years2.00
Anderson & Felson271971–75Cohort (US): Sample aged 35 to 64 years (n = 1853)Knee bending demand of job at time of interview (dichotomous variable)K&L⩾235–44 years0.85(0.20 to 3.61)
45–54 years0.82(0.32 to 2.11)
55–64 years2.45(1.21 to 4.97)
Sahlström & Montgomery491982–86Case control (Sweden). Cases: knee pain and radiographic OA (n = 340). Controls: random selection from population registers (n = 680).Degree of knee moment for working activity over three 15 year periodsAhlbäck⩾1Medium/heavy1.10(0.70 to 1.80)
Knee pain
O’Reilly et al50Not specifedUK postal survey to patients of two GP practices (n = 1961)Job title (longest held job)Knee painMiners1.90(1.30 to 2.80)
Manninen et al531992–93Case control (Finland). Cases: knee arthroplasty (n = 55). Controls: random sample from population registry (n = 140)Time spent squatting or kneeling in job at age 49 yearsKnee arthroplasty<2 hours per day0.58(0.21 to 1.64)
⩾2 hours per day1.68(0.66 to 4.28)
Miranda et al171994–95Cohort (Finland). Employed by forestry company (n = 3312).Time spent working in a kneeling or squatting position.Knee painHigh exposure1.30(0.70 to 2.30)
Weak evidence
Vingård et al451980Cohort (Sweden). Hospital care for OA of the knee born 1905 and 1945 reporting same occupation in two consecutive censuses (n = 221).Occupational exposure to forces on the lower extremities (high v low)Hospital careBorn 1905–241.20(0.90 to 1.50)
Born 1925–451.40(1.10 to 1.90)