biomechanics and load in the workhab functional capacity

Biomechanics and Load in the

WorkHab Functional Capacity

Evaluation: An Update

Dr Carole James

School of Health Sciences,

The University of Newcastle, Australia.

FCE: 2018

FCE 2018

School of Health Sciences

2

Effect of Load on Biomechanics in the WorkHab FCE

• Safe Maximal Lift = maximum load that an individual is able to safely lift.

Purpose:

• To evaluate any change in biomechanics between

safe minimum and safe maximum lifts during the

WorkHab FCE.

FCE 2014

School of Health Sciences

3

Effect of Load on Biomechanics in the WorkHab FCE

Method:

Experimental laboratory

based study

Sample: 30

healthy volunteers

Health Questionnaire,

BP 3 min step test Joints marked – foam ball/

ink

Wrist, Elbow, Shoulder, Hip, Knee, Ankle,

Spinous processes:

C7,T7,L3,S2

Darfish ProSuite

Min + Max lift Lift ÷ 1/3rds Calculation of joint angles

•Data analysis: Descriptive + Paired t-test

Digital recording of

lifting component

Rear Coronal + Right

sagittal planes

Angles 4

Ankle Knee Hip Lumbar Elbow Shoulder

Spine

School of Health Sciences

5

Effect of Load on Biomechanics in the WorkHab FCE

Results – Overhead lift

Green = Overhead (P values)

Joint 0/3 1/3 2/3 3/3

Ulnar deviation 0.007 0.016 0.004 <0.001

Elbow flexion 0.023 0.005 0.004 #

Shoulder 0.007 0.0036 # 0.038

Thoracic

extension

# 0.05 # 0.001

Lumbar extension # # 0.027 0.003

FCE 2018

School of Health Sciences

6

Effect of Load on Biomechanics in the WorkHab FCE

Results – Floor to Bench Lift

Red = Floor to Bench (P values)

Joint 0/3 1/3 2/3 3/3

Lumbar flexion 0.001(d) # # #

Hip flexion <0.001(d) 0.021(a) <0.007(d) <0.001(d)

Knee flexion 0.027(a) 0.005(d) # 0.004(d)

Ankle <0.001(a) 0.019(d) 0.001(d) <0.001(d+a)

FCE 2018

School of Health Sciences

7

Effect of Load on Biomechanics in the WorkHab FCE

Results – Bench to Shoulder Lift

Blue = Bench to Shoulder (P values)

Joint 0/3 1/3 2/3 3/3

Lumbar extension # # # #

Elbow 0.000 (d) 0.008 (a) # 0.009 (a)(d)

Shoulder 0.000 (d) # # 0.000 (a)

Thoracic

extension

# # # 0.004(a)

FCE 2018

School of Health Sciences

8

Ulnar deviation:

• peaked at 36.16 degrees two thirds of the way through the lift

• participants reaching end range during their safe maximal lift

Elbow:

• Participants inclined to keep the load closer to their body when it

was heavier by increasing elbow flexion

Shoulder:

• Shoulder flexion increased despite the overhead lift height remaining the same

Thoracic and Lumbar Spines

• Both in increased extension in parts of the maximum lift

Hip, Knee and Ankle

• Lack of findings

Effect of Load on Biomechanics in the WorkHab FCE

Discussion – Overhead lift

FCE 2018

School of Health Sciences

9

Lumbar

• less hyperextended when lifting maximum weights.

• start point of the descending phase where weights were being lifted

off the bench = significant difference

The hip

• ↑ flexion when lifting the load from the bench (0/3 point of the

descending phase) and placing the load back on the bench (2/3

and 3/3 points of the ascending phase).

• more likely to be in hyperextension when lifting min vs max wgts.

Knee

• minimal changes are noticed in knee joint angle between minimum

and maximum lift.

Ankle joint

• reduction in dorsiflexion when lifting maximum weights

Effect of Load on Biomechanics in the WorkHab FCE

Discussion – Floor to bench lift

School of Health Sciences

10

Lumbar

• No significant difference in lumbar spine extension ascending or

descending

Elbow

• ↓ flexion at 1/3 ascending

• ↑ flexion 3/3 ascending and 0/3 descending – highest point, harder

to keep close to body

Shoulder

• ↑ flexion 3/3 ascending and 0/3 descending – highest point, harder

to keep close to body

Thoracic

• ↑ extension at 3/3 ascending – longer lever arm

Effect of Load on Biomechanics in the WorkHab FCE

Discussion –Bench to Shoulder

School of Health Sciences

11

Kinematic changes important in determining SML

Elbow and shoulder flexion – OH

Hip, Ankle, lumbar – FB

Elbow and shoulder – BS

Changes in joint angles support assessors clinical reasoning and observations of SML

Consideration of handle placement with lifting

Effect of Load on Biomechanics in the WorkHab FCE

Discussion

FCE 2018

School of Health Sciences

12

Burgess-Limerick, R. (2003). "Squat, stoop, or something in between?" International Journal of Industrial Ergonomics 31: 143-

148.

West, N., Snodgrass, S. J., & James, C. (2018). The effect of load on biomechanics of the back and upper limb in a bench to

shoulder lift during the WorkHab Functional Capacity Evaluation. Work, 59(2), 201-210. doi:10.3233/WOR-172677

Melino, N. L., James, C.L., & Snodgrass, S. J. (2013). The effect of load in a floor-to-bench lift during the WorkHab Functional

Capacity Evaluation. Work: A Journal of Prevention, Assessment and Rehabilitation, ePub. doi:10.3233/WOR-131698

Allen, J. L., James, C.L., & Snodgrass, S. J. (2012). The effect of load on biomechanics during an overhead lift in the WorkHab

Functional Capacity Evaluation. Work, 43(4), 487-496. doi:10.3233/WOR-2012-1386

Gardener, L. and K. McKenna (1999). "Reliability of occupational therapists in determining safe, maximal lifting capacity."

Australian Occupational Therapy Journal 46: 110-119.

Gross, D. and M. Battie (2002). "Reliability of safe maximum lifting determinations of a functional capacity evaluation." Physical

Therapy 82(4): 364-372.

Isernhagen, S. (1992). "Functional capacity evaluation: rationale, procedure, utility of the kinesiophysical approach." Journal of

Occupational Rehabilitation 2(3): 157-168.

James, C., L. Mackenzie, et al. (2010). "Test-retest reliability of the manual handling component of the Workhab functional

capacity evaluation in healthy adults." Disability and Rehabilitation 32(22): 1863-1869.

Straker, L. (2003). Evidence to support using a squat, semi-squat and stoop techniques to lift low-lying objects. International

Journal of Industrial Ergonomics, 31(3).

Schipplein, O., Trafimow, J., Andersson, G., & Andriacchi, T. (1990). Relationship between moments at the L5/S1 level, hip and

knee joint when lifting. Journal of Biomechanics, 23(9), 907-912.

Arjmand, N., Shirazi-Adl, A. (2005). Biomechanics of Changes in Lumbar Posture in Static Lifting. Spine, 30, 2637-2648

Bonato, P., Ebenbichler, G., ROy, S. H., Lehr, S., Posch, M., Kollmitzer, J., et al. (2003). Muscle Fatigue and Fatigue-Related

Biomechanical Changes During a Cyclic Lifting Task. Spine, 28(16), 1810-1820..

Nielson, P. K., Andersen, L., & Jorgensen, K. (1998). The muscular load on the lower back and shoulders due to lifting at different

lifting heights and frequencies. Applied Ergonomics(29), 45-50.

Snook, S. H., & Ciriello, V. M. (1991). The design of manual handling tasks: revised tables of maximum acceptable weights and

forces. Ergonomics, 34(9), 1197-1213

Effect of Load on Biomechanics in the WorkHab FCE

References: