Monique Lortie

Prognostic factors for return to work after a first compensated episode of back pain.

OBJECTIVES--To determine which factors measured at baseline and during the course of treatment influence time to return to work after a first compensated episode of back pain. METHODS--The design is a treatment inception cohort including 305 compensated workers out of 402 eligible ones presenting at two rehabilitation centres for conventional treatment. Crude and adjusted rate ratios (RRs) along with 95% confidence intervals (95% CIs) were estimated with the Coxs proportional hazards regression. RESULTS--50% of workers had not returned to work after 112 days of follow up, and 11.3% still had not after 270 days. At the end of the study period (maximum follow up time was 1228 days), 230 workers (75.4%) had returned to work, 6.5% had not, and a similar percentage had retired, gone into vocational training, or returned to school. In the final model stratified for radiating pain during treatment, which was an important prognostic variable, workers between 21 to 30 years of age had a greater chance of returning to work (RR (95% CI) 1.43 (1.04 to 1.98) than those > or = 30. The other factors associated with a greater chance of returning to work were: a diagnosis of sprain or pain upsilon a diagnosis of intervertebral disc disorder (2.20 (1.23-3.91)), < 30 days of waiting between the accident and the beginning of treatment (1.30 (0.96 to 1.77)), a good flexion at baseline (1.52 (1.04 to 2.23)), absence of neurological symptoms during treatment (1.40 (0.98-2.00)), > 24 months of employment in the industry (1.49 (1.10 to 2.03)), working for a public industry upsilon a private one (1.63 (1.21 to 2.19)), and the ability to take unscheduled breaks (1.45 (1.06 to 1.97)). CONCLUSIONS--Even with a first episode of back pain, time to return to work is long and the proportion not returning is high. Return to work as expected is influenced by disease and host characteristics but also by social and work factors. Reinstatement programmes should account for all these factors.

Manual handling techniques: Comparing novices and experts

Abstract The purpose of this study was to compare the techniques used by six expert handlers and six novices during a free handling task. Each subject had to transfer three sets of 16 boxes from a platform to a four-wheel cart. The observations dealt with the position of the subject at the beginning of transfer and at deposit (position of the back, knees and feet, pelvic orientation, position of the hands), his way of moving during the transfer (position of the feet) and his way of positioning and moving the box during handling (tilt). The results show that the expert handlers chose handling techniques rather different than those of the novices, particularly with regard to the position of the knees, feet and pelvis, the location of the grip, the movement of the feet during transfer, and the position of the box during handling. The study suggests that the strategies adopted by the experts would improve balance, and permit better control of the load and more efficient use of box momentum during transfer.

Lumbo-sacral loads and selected muscle activity while turning patients in bed

Handling patients in bed using a pique (a waterproof padded sheet placed under the patient) is associated with a high incidence of risks for the spine with, in particular, the activity of pulling and turning the patient with the pique representing the highest risk. Fifteen female nursing aides were evaluated for compression and shear forces at the L5/S1 joint and for selected muscular activities in the trunk and shoulders. Films, force platforms and EMG recordings supplied the data; dynamic segmental analyses were performed to calculate reaction forces at L5/S1, and a planar single-muscle equivalent was used to estimate internal loads. Different execution parameters were examined including execution velocity, height of bed, direction of effort, leg position and knee support. A ‘free’ task, and a manual task not involving the pique, were also investigated. Recommendations are made for reducing spinal loading. The results also suggest that a change of direction in the trunk motion may present some risks whe...

Training in handling: an evaluative study.

Training programmes in handling have been one of the most used means of preventing work-related backache. The effectiveness of these programmes has not yet been demonstrated however, since they have rarely been evaluated. The purpose of this study was precisely to assess one of these programmes in the hospital sector which specifically dealt with the handling of patients. A field study was conducted and handling methods used by 32 trained orderlies were characterized using an observational grid developed and validated specifically to describe patient handling operations. The extent to which these orderlies used the handling methods taught was determined, and the observed deviations from these methods were characterized and interpreted. The results show that the handling principles taught (working with a straight back using the legs) were not frequently used in the workplace. Furthermore, the use of training was closely related to the type of handling carried out. In handling operations in which the effort includes a horizontal component (mainly those carried out in bed) the training was hardly used, while in vertical handling operations the taught principles were more frequently used. These results suggest that actual training is not well adapted to the handling of patients, particularly to horizontal handling carried out in the bed. Two main deficiencies in the actual programmes are pointed out. First, it is shown that, for reasons of physical constraints, training could not always be applied; second, the rationale of the taught principles could also be questioned, particularly the emphasis given to the use of the legs.

Comparison of spinal health indicators in predicting spinal status in a 1-year longitudinal study

A 1-year longitudinal study was performed to assess and compare the predictive qualities of spinal health indicators (excluding the cervical spine) among aircraft assembly workers having at least 1 year seniority in a large assembly plant. Ten health indicators were compared to determine their sensitivity and predictive power with regard to back compensation and absenteeism in 12 months follow-up, and the presence of any limitation at work due to the back, or symptoms to the back at the end of the interval. The initial response to a self-administered questionnaire was obtained from 269 male workers, of whom 205 (76.2%) completed the follow-up questionnaire. Initial prevalence of symptoms to the back was 42.3%, limitation in performing at work was 28.1%, consultation of a health professional was 7.3%, and a history of compensation for the back (ever) was reported by 30.4%. During the year of follow-up, 16 (6%) of the 269 workers initially enrolled were granted 17 compensated episodes. Of the 205 workers who responded to the follow-up, 33 (16.1%) have been absent from work (with or without compensation) because of their back. The presence, at the beginning of the study, of a limitation in performing at work or in activities of daily living and a history of compensation (ever) were the three indicators independently associated with the occurrence of compensation or absenteeism (total work disability) related to a back problem during the following year. The three indicators combined (either one positive at beginning of the study) had a sensitivity rate of 81.8% and a predictive power rate of 28.4% (predicting total work disability). These results are the best ever published for a spinal health indicator measured from a survey questionnaire. Besides acceptable predictive qualities, the combined indicator predicted work disability from predisability states. Its value for targeting interventions in industry aimed at preventing the worsening of early stages of spinal disorders toward disabling conditions, remains to be tested.

Observation Procedures Characterizing Occupational Physical Activities: Critical Review

The first objective of this paper is to compare the observation procedures proposed to characterize physical work. The second objective is to examine the following 3 methodological issues: reliability, observer training, and internal validity. Seventy-two papers were reviewed, 38 of which proposed a new or modified observation grid. The observation variables identified were broken down into 7 categories as follows: posture, exertion, load handled, work environment, use of feet, use of hands, and activities or tasks performed. The review revealed the variability of existing procedures. The examination of methodological issues showed that observation data can be reliable and can present an adequate internal validity. However, little information about the conditions necessary to achieve good reliability was available.

The classification of accident data

The objectives of this paper were to document how accident data are usually classified, whether this system makes it possible to classify all the data contained in the accident reports, and to examine the classification problems encountered. The first part reviews the variables retained and descriptors used by the accident studies published over the past 10 years. This synopsis showed that the types of data considered and the manner in which they were classified varied greatly between the studies. Data on the accident circumstances (e.g. activity and incidents) were seldom considered, while accident and injury data were extensively analyzed. The second part analyzes the vocabulary and data reported by injured handlers in 580 accident descriptions. Possible grouping vocabulary strategies were explored and the importance of the implicit nature of data was evaluated. This revealed that the vocabulary used by the injured was both rich and variable. For example, over 80 terms were used to describe one activity. While some grouping strategies to classify data could be developed for the worksite or incidents, it was particularly difficult to identify a logic for grouping activity data. Also, the analysis showed that many important data are of an implicit nature. A literal or automatic classification of terms may, therefore, lead to significant biases. Furthermore, although data on incidents were frequently reported, this type of data is generally disregarded by most accident studies. Finally, the paper discusses various classification problems that emerged.

Analyse comparative des accidents déclarés par des préposés hommes et femmes d'un hôpital gériatrique

Abstract Lortie, M., 1987. Comparative analysis of accidents reported by male and female orderlies in a geriatric hospital. Journal of Occupational Accidents , 9: 59–81. The circumstances of 662 accidents reported by male and female orderlies in a geriatric hospital were compared according to the following variables: the type of handling task carried out at the time of accident, the action causing the injury, the equipment involved (as place of handling or as tool used to handle) and the injured body area. Male and female orderlies performed the same job but worked only with patients and co-workers of their own sex. The most important results were: Females reported accidents related to an in-place handling task more often than males, the most frequent actions involved consisting in turning or moving the patient to the head of the bed. Accidents related to transferring and lifting tasks were on the contrary the most frequent ones reported by males. No male-female differences were observed as to the distribution of the places of handling involved in the accident nor of the body areas injured. However, handling tasks and places were associated with statistically significant different patterns of injured areas. Also given a specific place, the reported circumstances of accidents appeared to differ significantly between male and female orderlies. Results suggest that the work organisation and the handling methods play a major role in the subsequent pattern of accidents. However these work methods are strongly related to workers sex.

Examination of biomechanical principles in a patient handling task

Handling patients in bed using a pique (a waterproof padded sheet placed under the patient) with, in particular, the activity of pulling and turning the patient, is associated with a high incidence of risks for the spine. Six female subjects, not experienced with the task, were evaluated for spinal loadings at the L5/S1 joint, for selected muscular activities in the trunk and shoulders and for work-energy factors. Films, force platforms and EMG recordings supplied the data; dynamic segmental analyses were performed to calculate reaction forces at L5/S1, and a planar single-muscle equivalent was used to estimate internal loads. Three treatments were administered which allowed comparisons to be made for two hand grip positions on the pique (close to the patient vs. a 15 cm distance) and two movement patterns (continuous vs. interrupted with a pause). It was hypothesized that moving the hand grips away from the patient would favour a straighter-back position and a reduction of spinal loadings; it was also hypothesized that non-interrupted motions involving changes of direction of efforts would be more strenuous for the spine. Analyses of variance with repeated measures were conducted and the locations of significant differences were made with Scheffe method of multiple comparisons. Conflicting results were obtained for the hand grip positions but the results suggest that the partition of a task into several operations (with pauses) is indicated. Recommendations are made to examine more thoroughly trunk postures or back curvatures in relation to spinal loadings.

Assessment of factors considered to be important in handling tasks by expert handlers

Twenty-eight experienced handlers, considered the best in two transport companies, were interviewed using a questionnaire consisting of partially closed-ended questions. They had to assess 20 videotape handling sequences showing two different handling methods to determine, for 10 factors and overall, which one was the best. They were asked about the inportance of these factors in their choices of the best method. The aims of the study were to verify whether there was a consensus among experienced handlers as to what was a good handling method and to identify the factors taken into consideration by them. Results show the lack of consensus on the best methods. Handlers favor different strategies depending on the worjk context and their own priorities.