The purpose of this case study was to investigate reflex inhibition of the quadriceps femoris in a subject with postsurgical edema of the left knee. The subject was a 45-year-old male with a traumatic knee injury with resultant edema who underwent elective arthroscopic surgery. Reflex inhibition was assessed by H-reflex elicitation in the femoral nerve and surface electromyography of the quadriceps. To assess the degree of edema, direct circumferential measurements were taken. On the first presurgical visit, the left knee demonstrated mild edema with a decrease in H-reflex amplitudes. Two days after surgery, a further reduction in amplitudes and more swelling were demonstrated followed by an increase in amplitudes and a reduction in edema on the 28th postoperative day. These findings document a relationship between reflex inhibition and joint swelling that was previously described in experimental models where joint edema was simulated.
Andrew L. McDonough and Joseph P. Weir
Louise M. Thoma, David C. Flanigan, Ajit M. Chaudhari, Robert A. Siston, Thomas M. Best and Laura C. Schmitt
Few objective data are available regarding strength and movement patterns in individuals with articular cartilage defects (ACDs) of the knee.
To test the following hypotheses: (1) The involved limb of individuals with ACDs would demonstrate lower peak knee-flexion angle, peak internal knee-extension moment, and peak vertical ground-reaction force (vGRF) than the contralateral limb and healthy controls. (2) On the involved limb of individuals with ACDs, quadriceps femoris strength would positively correlate with peak knee-flexion angle, peak internal knee-extension moment, and peak vGRF.
Biomechanics research laboratory.
11 individuals with ACDs in the knee who were eligible for surgical cartilage restoration and 10 healthy controls.
Quadriceps femoris strength was quantified as peak isometric knee-extension torque via an isokinetic dynamometer. Sagittal-plane knee kinematics and kinetics were measured during the stance phase of stair ascent with 3-dimensional motion analysis.
Main Outcome Measures:
Quadriceps strength and knee biomechanics during stair ascent were compared between the involved and contralateral limbs of participants with ACD (paired t tests) and with a control group (independent-samples t tests). Pearson correlations evaluated relationships between strength and stair-ascent biomechanics.
Lower quadriceps strength and peak internal knee-extension moments were observed in the involved limb than in the contralateral limb (P < .01) and the control group (P < .01). For the involved limb of the ACD group, quadriceps femoris strength was strongly correlated (r = .847) with involved-limb peak internal knee-extension moment and inversely correlated (r = −.635) with contralateral peak vGRF. Conclusions: Individuals with ACDs demonstrated deficits in quadriceps femoris strength with associated alterations in movement patterns during stair ascent. The results of this study are not comprehensive; further research is needed to understand the physiological characteristics, activity performance, and movement quality in this population.
Dae-Hyun Kim, Jin-Hee Lee, Seul-Min Yu and Chang-Man An
The quadriceps femoris (QF) is the strongest muscle in the human body and is an important factor in activities of daily living and sports activity. 1 , 2 QF weakening is known as a potential component of musculoskeletal disorders, such as knee degenerative arthritis, ligament injury, and
Wolfgang Seiberl, Daniel Hahn, Florian Kreuzpointner, Ansgar Schwirtz and Uwe Gastmann
The purpose of this study was to investigate if force enhancement (FE) in vivo is influenced by stretch-induced changes of muscle architecture. Therefore, 18 subjects performed maximum voluntary isometric (100° knee flexion angle) and isometric-eccentric-isometric stretch contractions (80°–100° ω = 60°s−1) whereby pennation angle and fascicle length of vastus lateralis was determined using ultrasonography. We found significant (2-way repeated ANOVA; α = 0.05) enhanced torque of 5–10% after stretch as well as significant passive FE but no significant differences in muscle architecture between isometric and stretch contractions at final knee angle. Furthermore, EMG recordings during a follow-up study (n = 10) did not show significant differences in activation and mean frequency of contraction conditions. These results indicate that FE in vivo is not influenced by muscle architectural changes due to stretch.
Atsuki Fukutani and Toshiyuki Kurihara
Recent studies have reported that resistance training increases the cross-sectional areas (CSAs) of tendons; however, this finding has not been consistently observed across different studies. If tendon CSA increases through resistance training, resistance-trained individuals should have larger tendon CSAs as compared with untrained individuals. Therefore, in the current study, we aimed to investigate whether resistance training increases tendon CSAs by comparing resistance-trained and untrained individuals. Sixteen males, who were either body builders or rugby players, were recruited as the training group, and 11 males, who did not participate in regular resistance training, were recruited into the control group. Tendon CSAs and muscle volumes of the triceps brachii, quadriceps femoris, and triceps surae were calculated from images obtained by using magnetic resonance imaging. The volumes of the 3 muscles were significantly higher in the training group than in the control group (P < .001 for all muscles). However, a significant difference in tendon CSAs was found only for the distal portion of the triceps surae tendon (P = .041). These findings indicate that tendon CSA is not associated with muscle volume, suggesting that resistance training does not increase tendon CSA.
Karinna Sonálya Aires da Costa, Daniel Tezoni Borges, Liane de Brito Macedo, Caio Alano de Almeida Lins and Jamilson Simões Brasileiro
muscles is related to strength deficits. It can lead to functional decline in these individuals. 1 , 2 In particular, quadriceps femoris weakness is a primary impairment following ACL reconstruction, 3 and improvement of quadriceps femoris strength is an important factor in improving functional outcomes
Taija Finni and Sulin Cheng
The positions of EMG electrodes over the knee extensor muscles were examined in 19 healthy men using MR images; electrodes were placed according to the SENIAM (surface electromyography for non-invasive assessment of muscles) guidelines. From axial images, the medial and lateral borders of the muscles were identified, and the arc length of the muscle surface was measured. The electrode location was expressed as a percentage value from the muscle’s medial border. EMGs were recorded during isometric maximal contraction, squat jumps, and countermovement jumps and analyzed for cross-correlation. The results showed that variations in lateral positioning were greatest in vastus medialis (47% SD 11) and rectus femoris (68% SD 15). In vastus lateralis, the electrode was usually placed close to the rectus femoris (19% SD 6). The peak cross-correlation coefficient varied between 0.15 and 0.68, but was not associated with electrode location. It is recommended that careful consideration is given to the medial-lateral positioning of the vastus lateralis electrodes especially, so that the electrodes are positioned over the mid-muscle rather than in close proximity to rectus femoris.
Anna Lina Rahlf, Klaus-Michael Braumann and Astrid Zech
third of the quadriceps femoris muscle. The medial and lateral straps were applied in 45° knee flexion along the collateral medial and lateral ligaments. Patients in the sham group received a tape distal to the knee without tension and without affecting the knee joint (Figure 2B ). The tape was applied
Tarik Ozmen, Mert Aydogmus, Hanife Dogan, Derya Acar, Tuba Zoroglu and Mark Willems
Kinesio taping (KT) is a taping technique extensively used in rehabilitation of sports injuries; however, the effect of KT on delayed-onset muscle soreness is not entirely clear.
To investigate the effect of kinesio tape on the quadriceps femoris on muscle pain, flexibility, and sprint performance after squat exercise.
University research laboratory.
19 female university students (age 21.0 ± 1.2 y, weight 53.0 ± 4.6 kg, height 164 ± 4 cm).
Main Outcome Measures:
Pressure-pain threshold for quadriceps femoris was recorded using pressure algometry. Quadriceps femoris flexibility was measured as the range of motion of knee flexion with a stainless steel goniometer. Sprint-speed measurements were conducted using photocells placed at 0 and 20 m. All participants completed both conditions (KT application and no KT application) after a 1-wk washout period. Measurements were taken at baseline and 48 h postexercise. For the KT condition, KT was applied immediately before the exercise protocol and remained on the skin for 48 h.
Squat exercise reduced flexibility and increased pain and sprint time compared with baseline. KT application resulted in similar sprint time and muscle pain as the no-KT condition but maintained flexibility compared with baseline.
KT application immediately before squat exercise has no effect on muscle pain and short sprint performance but maintains muscle flexibility at 2 days of recovery.
Kenneth Meijer, Peter Bosch, Maarten F. Bobbert, Arthur J. van Soest and Peter A. Huijing
The influence of parameter values (i.e., fiber optimum lengths and moment arms) and simplification of the geometry of a Hill-type muscle model on the prediction of normalized maximal isometric knee extension moment to knee joint angle relationship was studied. For that purpose, the geometry of m. quadriceps femoris was modeled in considerable detail, and all parameter values were determined on one set of cadaver specimens that had been selected for muscular appearance. The predicted relationship was compared to that measured in human subjects over the full range of physiological knee angles, and a good correspondence was found (r = .96). The good correspondence could be attributed to the substitution of realistic parameter values into the model. Incorporating complex muscle geometry into the model resulted in a small additional improvement of the prediction. It was speculated that the variation in results of cadaver measurements among studies reflects true differences caused by individuals' levels of physical activity in the period preceding death.