Noninvasive assessment of peripheral skeletal muscle weakness in idiopathic pulmonary fibrosis: a pilot study with multiparametric MRI of the rectus femoris muscle

Background: To investigate differences in magnetic resonance imaging (MRI) features of rectus femoris muscle between idiopathic pulmonary fibrosis (IPF) patients and healthy volunteers.Methods: Thirteen IPF patients with GAP Index stage II disease were subjected to pulmonary function tests, 6-minute walk test (6MWT), quadriceps femoris muscle strength measurement and MRI of the thigh at rest. At MRI, muscle cross-sectional areas, T2 and T2* relaxometry, and 3-point Dixon fat fraction were measured. The results were compared to those of eight healthy sedentary volunteers.Results: IPF patients had significantly lower %predicted FVC, FEV1 and DLCO (p<0.001 for the three variables) and walked significantly less in the 6MWT (p=0.008). Mean quadriceps femoris muscle strength also was significantly lower in IPF patients (p=0.041). Rectus femoris muscle T2* measurements were significantly shorter in IPF patients (p=0.027). No significant intergroup difference was found regarding average muscle cross-sectional areas (p=0.790 for quadriceps and p=0.816 for rectus femoris) or rectus femoris fat fraction (p=0.901). Rectus femoris T2 values showed a non-significant trend to be shorter in IPF patients (p=0.055).Conclusions: Our preliminary findings suggest that, besides disuse atrophy, other factors such as hypoxia (but not inflammation) may play a role in the peripheral skeletal muscle dysfunction observed in IPF patients. This might impact the rehabilitation strategies for IPF patients and warrants further investigation.

Efek Prehabilitation Exercise dengan Resistance Band terhadap Kekuatan Otot Kuadrisep Femoris pada Pasien Total Knee Replacement

Pendahuluan: Prehabilitation exercise dengan resistance band merupakan latihan penguatan otot yang aman, mudah dilakukan dan dapat dijadikan sebagai home programme pada pasien osteoartritis (OA) yang akan menjalani total knee replacement (TKR). Namun demikian, latihan ini belum lazim dilakukan di Indonesia. Penelitian ini bertujuan untuk mengetahui pengaruh intervensi prehabilitation exercise dengan resistance band terhadap kekuatan otot kuadrisep femoris pada pasien yang menjalani TKR. Metode: Penelitian randomized controlled trial dengan pre and post test. Sebanyak 16 subjek yang memenuhi kriteria dibagi secara acak ke dalam kelompok perlakuan (n=8) dan kontrol (n=8). Kelompok perlakuan mendapatkan prehabilitation exercise dengan resistance band 3x seminggu selama 4 minggu sebelum TKR, sedangkan kelompok kontrol mendapatkan terapi konvensional berupa ergocycle dan TENS (Transcutaneus Electrical Nerve Stimulation) 2x seminggu selama 4 minggu sebelum TKR. Pengukuran kekuatan otot kuadrisep femoris dilakukan 3x yaitu pada 4 minggu dan 1 minggu sebelum TKR, serta 8 minggu setelah TKR menggunakan push-pull dinamometer. Hasil: Kelompok perlakuan menunjukkan peningkatan kekuatan otot kuadrisep femoris yang signifikan pada 4 minggu ke 1 minggu sebelum TKR sebesar 3,00+1,28 (p=0,001). Peningkatan kekuatan otot pada kelompok intervensi juga terlihat pada 4 minggu sebelum ke 8 minggu setelah TKR sebesar 2,38+1,22 (p<0,001). Sebaliknya, kelompok kontrol mengalami penurunan kekuatan otot sebesar -0,88+0,79 (p=0,001) dan -0,88+1,28 (p=0,001) masing-masing pada periode 4 minggu ke 1 minggu sebelum TKR dan 4 minggu sebelum ke 8 minggu setelah TKR. Kesimpulan: Terdapat pengaruh prehabilitaion exercise dengan resistance bands terhadap peningkatan kekuatan otot kuadrisep femoris pada subjek yang menjalani operasai TKR. Prehabilitation exercise dapat digunakan sebagai alternatif latihan yang aman, mudah dilakukan serta dapat dijadikan sebagai home programme pada pasien yang akan menjalani operasi TKR. Kata kunci: Prehabilitation exercise, kekuatan kuadrisep femoris, total knee replacement. Background: Prehabilitation exercises using resistance band is a safe and easy muscle strengthening exercise and can be used as a home programme in OA patients undergoing TKR. This exercise, however, is not commonly used in Indonesia. The this study aims to investigate the effect of prehabilitation exercise using resistance band on quadriceps femoris muscle strength in patients undergoing TKR. Methods: This study is a randomized controlled trial with pre and post-test. A total of 16 subjects who meet criteria were randomly allocated into intervention (n = 8) and control (n = 8) groups. The first group received prehabilitation exercise with resistance bands 3 times a week for 4 weeks before TKR, while the control group received conventional therapies involving ergocycle and TENS (Transcutaneous Electrical Nerve Stimulation) 2 times a week for 4 weeks before TKR. Quadriceps femoris muscle strength was measured three times at 4 weeks and 1 week before TKR, and 8 weeks after TKR using a push-pull dynamometer. Results: The intervention group shows a significant increase in quadriceps femoris muscle strength at 4 weeks to 1 week before TKR (3.00+1.28, p = 0.001). The increased quadriceps femoris muscle strength in the intervention group was also seen at 4 weeks before to 8 weeks after TKR (2,38+1,22, p<0,001). Conversely, the control group experienced a decreased quadriceps femoris muscle strength of -0.88+0.79 (p=0.001) and -0.88+1.28 (p=0.001) respectively in the period of 4 weeks to 1 week before TKR and 4 weeks before to 8 weeks after TKR. Conclusion: There is an effect of prehabilitation exercise with resistance bands on increased quadriceps femoris muscle strength in subjects undergoing TKR. Prehabilitation exercise is safe, easy and can be used as an alternative for home programme. Keywords: Prehabilitation exercise, quadriceps femoris muscle strength, total knee replacement.

Analysis of three different equations for predicting quadriceps femoris muscle strength in patients with COPD

Objective: To compare equations for predicting peak quadriceps femoris (QF) muscle force; to determine the agreement among the equations in identifying QF muscle weakness in COPD patients; and to assess the differences in characteristics among the groups of patients classified as having or not having QF muscle weakness by each equation.Methods: Fifty-six COPD patients underwent assessment of peak QF muscle force by dynamometry (maximal voluntary isometric contraction of knee extension). Predicted values were calculated with three equations: an age-height-weight-gender equation (Eq-AHWG); an age-weight-gender equation (Eq-AWG); and an age-fat-free mass-gender equation (Eq-AFFMG).Results: Comparison of the percentage of predicted values obtained with the three equations showed that the Eq-AHWG gave higher values than did the Eq-AWG and Eq-AFFMG, with no difference between the last two. The Eq-AHWG showed moderate agreement with the Eq-AWG and Eq-AFFMG, whereas the last two also showed moderate, albeit lower, agreement with each other. In the sample as a whole, QF muscle weakness (< 80% of predicted) was identified by the Eq-AHWG, Eq-AWG, and Eq-AFFMG in 59%, 68%, and 70% of the patients, respectively (p > 0.05). Age, fat-free mass, and body mass index are characteristics that differentiate between patients with and without QF muscle weakness.Conclusions: The three equations were statistically equivalent in classifying COPD patients as having or not having QF muscle weakness. However, the Eq-AHWG gave higher peak force values than did the Eq-AWG and the Eq-AFFMG, as well as showing greater agreement with the other equations.