gms | German Medical Science

Objective: Glioblastoma (GBM) is a primary brain tumour with frequently poor prognosis. Nevertheless, surgery, chemotherapy, and radiation are proven state of the art treatment options which are intended to improve quality of life and survival time of GBM-patients. Accompanying treatment normally includes the use of corticosteroids and of anticonvulsive medication. Especially these necessary “accompanying” medications can lead to myopathy with loss of muscle mass especially of thighs. Besides this, corticosteroids also lead to iatrogenic osteoporosis with the risk of fractures. In combination with the iatrogenic muscle weakness, deficits in coordination due to consequences of the brain tumour himself increase the risk of falls due to gait disturbances with the consequence of fractures and possible early dependency from others help. Therefore, the management of muscular strength seems to be of one goal of high importance in the group of GBM-patients to help them to maintain longer independency.

Aim of this pilot study was to describe muscle strength in GBM-patients and discuss rehabilitative options for these patients.

Material/Methods: Patients: after approval of the ethics committee (Medical University of Vienna), and after written informed consent, 37 patients (m:f=31:6, 54±12a, BMI=26±3 kg/m²) were included in this cross-sectional observation.

Assessment of muscular strength: Hand grip strength was measured by using a Jamar© hand-dynamometer. Isokinetic testing of knee extension and flexion strength was performed by using a Biodex3^© -dynamometer – two sets of five reciprocal isokinetic knee extension and flexion movements with an angular speed of 60°/sec were assessed.

Parts of this ongoing study have been published as master thesis at the Medical University of Vienna.

Results: During and after strength testing none adverse effects have been observed.

Handgrip strength: right hand=74±40 lbs; left hand=70±41 lbs.

Isokinetic testing of thigh muscles (peak torque/kg): right knee extensor muscles=159±52 Nm/kg; left knee extensor muscles=147±56 Nm/kg; right knee flexor muscles=75±38 Nm/kg, left knee flexor muscles=69±37 Nm/kg.

Conclusion: As expected, in this cross-sectional pilot study, GBM-patients showed low handgrip strength and extremely low isokinetic muscular strength of knee extensors and flexors in comparison to age and sex related expected values of the healthy population. However, the observed deficits in muscular strength seem to be more related to thigh muscles than to handgrip. For this patient group, physical medical treatment options should include active exercise to improve muscle strength, gait training, and fall prevention. Furthermore, neuromuscular electrical stimulation can be added in cases of GBM-patients with negative seizure history or sufficiently treated epilepsy. To our opinion, these rehabilitation options should be individually planned (within a tumour board for cancer rehabilitation) and to begin as early as possible.