Quadriceps function in elderly patients after proximal femoral fracture

Mitchell, Sarah L (2001) Quadriceps function in elderly patients after proximal femoral fracture. PhD thesis, University of Glasgow.

Abstract

The aims of this thesis were twofold. The first was to investigate the practicability, reproducibility and the validity of measurement of leg extensor power (LEP) in Osteoporotic and frail elderly people, in order to determine the changes associated with repeated measurements, and the ability of LEP to discriminate between different patient groups (an Osteoporotic group, frail elderly and patients who have sustained a fractured neck of femur). This was an observational study, using a convenience sample. A series of 10 measurements of LEP (using the Nottingham power rig) were made, with a 30 second rest between measurements. Ten repeated series of measurements were made at 3-day intervals in the Osteoporotic and in the PFF groups. All measurements were made by a single observer. There was a progressive increase in measured LEP over the first 5 attempts at a single visit in all the patient groups, after which performance stabilised and was relatively constant. There were also significant increases in LEP in the Osteoporotic and PFF groups when measured on a second occasion 3 days later, with a mean change of 3.8 Watts (SE 1.6, P=0.02) and 2.1 Watts (SE 0.5, P=0.02) respectively. There was no further significant improvement between a second and third series of measurements in the Osteoporotic group (mean change of -0.5, SE 2.8, P= 0.87). This study found significant increases in LEP with repeated measures at a single visit. This may have been due to a learning effect or a warming up effect of the muscle groups. We have taken the mean of the 6th to 10th measurements at a single visit as the summary measure of LEP. There were also significant increases in LEP when measurements were repeated after a 3-day interval. This was likely to be due to a learning effect. The second, and main aim of the work presented in this thesis was to determine whether systematic progressive high intensity quadriceps training increases leg extensor power and reduces disability in patients rehabilitating after proximal femoral fracture. This study was an open parallel group randomised controlled trial comparing 6 weeks of quadriceps training (40 patients) plus standard rehabilitation versus standard rehabilitation alone (40 patients). The training group exercised twice weekly, with 6 sets of 12 repetitions of knee extension (both legs), progressing up to 80% of their one- repetition maximum. The main outcome measures were leg extensor power (Nottingham Power Rig), functional mobility (Elderly Mobility Scale, which includes Functional Reach and a measure of gait speed), disability (Barthel Index) and perceived health status (Nottingham Health Profile). These were made at baseline, after 6 weeks (at the end of the intervention) and at 16 weeks. Leg extensor power increased significantly in the quadriceps-training group (fractured leg mean improvement at 6 weeks 157% (standard error 16), non-fractured leg 80% (12)) compared to the control group (63% (11) and 26% (8) respectively, unpaired Student t-test P=0.001 and P=0.001 for between group comparisons). Significant improvements in LEP in the quadriceps-training group were maintained at 16 weeks. The data from the intervention study was also used to examine the relationship between LEP/Kg and functional capacity. Correlations between LEP/Kg (fractured leg alone, and combined LEP, (fractured leg plus non-fractured leg)) and disability (Barthel) and functional scores (Elderly Mobility Scale, Sit to Stand, Timed Up and Go, Functional Reach and Gait Speed) and grip strength were determined by calculating Spearman's rank correlation. There were statistically significant correlations for LEP/Kg of the fractured leg and all functional scores with r values ranging between 0.39 and 0.65 for the quadriceps trained group at week 6. The strongest correlations were seen between LEP/Kg and the Elderly Mobility Scale (r=0.65). Similar results were seen for combined LEP/Kg at week 6 for the quadriceps trained group. When training induced changes in LEP/Kg and functional measures were analysed there was a significant correlation between change in LEP/Kg and change in gait speed (r=0.69). This was not the case for combined LEP/Kg. Therefore progressive high-intensity quadriceps training in elderly proximal femoral fracture patients increased leg extensor power and reduced disability. This was accompanied by an increase in energy as measured by the Nottingham Health Profile. This intervention may provide a simple practical way of improving outcome in these patients.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Adviser: David Stott
• Keywords: Kinesiology, Gerontology
• Date of Award: 2001
• Depositing User: Enlighten Team
• Unique ID: glathesis:2001-73812
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 14 Jun 2019 08:56
• Last Modified: 14 Jun 2019 08:56
• URI: https://theses.gla.ac.uk/id/eprint/73812