Effects of Age and ACL Reconstruction on Quadriceps Gamma Loop Function

Richardson, Miles; Cramer, Joel T.; Bemben, Debra A.; Shehab, Randa L.; Glover, John R.; Bemben, Michael G.

doi:10.1519/00139143-200604000-00006

Cited by 43 publications

(65 citation statements)

References 21 publications

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“…A study testing this hypothesis is currently being undertaken in our laboratory. In addition to the results presented in the current study, quadriceps γ-loop dysfunction has been observed after ACL injury [32,35], after ACL reconstructive surgery [36,42] and in elderly patients hospitalised after a fall [52]. Importantly, the mechanisms explaining γ-loop dysfunction may be different in different populations.…”

Section: Discussionsupporting

confidence: 57%

“…In people who have ruptured their anterior cruciate ligament (ACL), however, prolonged vibration has no effect on quadriceps muscle activation [32]. Similar observations have since been confirmed up to 20 months after ACL reconstruction [34-36]. These findings suggest that ACL rupture causes an impairment in normal Ia afferent feedback (termed γ-loop dysfunction) that limits quadriceps α-motoneuron depolarisation [32].…”

Section: Introductionmentioning

confidence: 94%

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Mechanisms of quadriceps muscle weakness in knee joint osteoarthritis: the effects of prolonged vibration on torque and muscle activation in osteoarthritic and healthy control subjects

2011

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IntroductionA consequence of knee joint osteoarthritis (OA) is an inability to fully activate the quadriceps muscles, a problem termed arthrogenic muscle inhibition (AMI). AMI leads to marked quadriceps weakness that impairs physical function and may hasten disease progression. The purpose of the present study was to determine whether γ-loop dysfunction contributes to AMI in people with knee joint OA.MethodsFifteen subjects with knee joint OA and 15 controls with no history of knee joint pathology participated in this study. Quadriceps and hamstrings peak isometric torque (Nm) and electromyography (EMG) amplitude were collected before and after 20 minutes of 50 Hz vibration applied to the infrapatellar tendon. Between-group differences in pre-vibration torque were analysed using a one-way analysis of covariance, with age, gender and body mass (kg) as the covariates. If the γ-loop is intact, vibration should decrease torque and EMG levels in the target muscle; if dysfunctional, then torque and EMG levels should not change following vibration. One-sample t tests were thus undertaken to analyse whether percentage changes in torque and EMG differed from zero after vibration in each group. In addition, analyses of covariance were utilised to analyse between-group differences in the percentage changes in torque and EMG following vibration.ResultsPre-vibration quadriceps torque was significantly lower in the OA group compared with the control group (P = 0.005). Following tendon vibration, quadriceps torque (P < 0.001) and EMG amplitude (P ≤0.001) decreased significantly in the control group but did not change in the OA group (all P > 0.299). Hamstrings torque and EMG amplitude were unchanged in both groups (all P > 0.204). The vibration-induced changes in quadriceps torque and EMG were significantly different between the OA and control groups (all P < 0.011). No between-group differences were observed for the change in hamstrings torque or EMG (all P > 0.554).Conclusionsγ-loop dysfunction may contribute to AMI in individuals with knee joint OA, partially explaining the marked quadriceps weakness and atrophy that is often observed in this population.

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Section: Discussionsupporting

confidence: 57%

Section: Introductionmentioning

confidence: 94%

Mechanisms of quadriceps muscle weakness in knee joint osteoarthritis: the effects of prolonged vibration on torque and muscle activation in osteoarthritic and healthy control subjects

2011

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“…Also the patients with ACL reconstruction demonstrate arthrogenic quadriceps inhibition in order to minimise anterior tibial translation and ACL graft strain [17]. During ACL reconstruction the gamma loop function could be attenuated in the quadriceps because the mechanoreceptors in the ACL are not surgically reconstructed [5,18]. In contrast to the quadriceps, the hamstrings are less susceptible to strength deficits following an ACL injury.…”

Section: Discussionmentioning

confidence: 99%

Effect of haemarthrosis on the rehabilitation of anterior cruciate ligament reconstruction- single bundle versus double bundle

Bahl

Goyal

Jain

et al. 2013

Journal of Orthopaedic Surgery and Research

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BackgroundHaemarthrosis and pain adversely affects the functional outcome of ACL reconstruction, especially in case of DB ACL reconstruction due to more extensive procedure. The purpose of the study was to evaluate the effect of haemarthrosis on the rehabilitation of DB ACL reconstruction versus SB ACL reconstruction.Methods100 patients were divided into two groups, of SB ACL and DB ACL reconstruction consisting of 50 patients each. An intra-articular drain was put in every patient. The pain was evaluated till week 8 using VAS (Visual Analog Scale). The Functional outcomes were evaluated using the Isokinetic Dynamometer at 3 and 6 months in both the groups. Muscle bulk and Range of motion were also noted in each group.ResultsThe results showed that there was statistically significant difference between the drain amount (n = 60.3 ml in SB ACL group vs. n = 94.2 ml in the DB ACL group) and haemarthrosis (n = 0.7 in SB ACL vs n = 1.5 in DB ACL) at week 1 post-operatively. Also the pain outcome improved on SB ACL after day 3 (VAS, n = 1.8) as compared to the DB ACL group (VAS, n = 3.7). The isokinetic muscle strength was found to be statistically significantly (p value < 0.05) better in the SB ACL group in the quadriceps muscle (both concentric and eccentric) at the end of the 3rd month. In the SB ACL group the Quadriceps Concentric strength deficit was 22.32% as compared to 34.12% in the DB ACL group. Both the groups had comparable flexor muscle strength at end of 3rd month. Both the groups had comparable muscle strength after 6 months of post-operative rehabilitation in both quadriceps and Hamstring muscle group.ConclusionWe noted that rehabilitation of DB ACL reconstruction group lags behind that of SB ACL reconstruction during the first 3 months due to post-operative haemarthrosis & its effects, but show comparable results after 6 months. The muscle strength measured isokinetically and the muscle bulk were found to be greater in the SB ACL group initially after 3 months but was found to be similar after 6 months.

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“…The authors concluded the associated muscle weakness from reconstructed ACL was probably due to a loss in c loop function of the quadricep muscle. In a similar study, Richardson et al 13 repeated the Konishi et al 69 protocol and reported that when 20 minutes of VT (50 Hz) was directly applied to the patellar tendon of young (23 years) healthy participants, isometric leg extensor MVC (27%) and EMG of quadriceps (212%) all decreased significantly. However, no significant changes were reported during the MVC or EMG activity in young (22 years) ACL reconstructed participants or in older (66 years) healthy people, where the authors claimed that c loop function !…”

Section: Injury Rehabilitationmentioning

confidence: 96%

“…Vibration therapy can be administered by direct or indirect methods, where electromotor devices have been directly applied to the muscle and/or tendon 12,13 or have been attached to resistance training equipment to elicit vibration transmission through cables of various machines to the whole body or body parts. 14 The vibratory load is dependent on four variables: frequency (f), displacement (D), acceleration (a), and duration (t).…”

Section: Application Of Vtmentioning

confidence: 99%

Good vibrations? – The use of vibration therapy for exercise recovery, injury prevention and rehabilitation

Cochrane

2011

Physical Therapy Reviews

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Background: There has been a resurgence of vibration technology and the application of direct and indirect vibration therapy (VT) has found its way into medical, clinical, and rehabilitation fields. Direct (applied to the area) and indirect (transferred to the whole body or body part) VT have been reported to enhance muscle force, power, and flexibility, and raise intra-muscular temperature, which is fundamental to injury prevention and exercise-associated rehabilitation and may reduce pain. Objectives: To provide a discussion on the scientific merit of the limited evidence for direct and indirect VT. Major findings: Direct VT is supported for reducing pain. However, it is equivocal whether indirect VT has the same effect to reduce delayed onset of muscle soreness. Indirect VT has potential to alleviate muscle soreness symptoms and can improve static balance in the elderly and compromised health groups. It is unclear whether indirect VT increases reflex activity to increase joint stability and reduce possible muscle strains. Nevertheless, indirect VT increases intramuscular muscle temperature at a faster rate compared to conventional warm-up intervention, which would prove useful in exercise-associated rehabilitation. Indirect VT may have other additional benefits: it increases torque and range of motion in chronic lower back pain; maintains cartilage integrity when weight-bearing activities are difficult to achieve; increases knee extensor force and decreases sensory deficits in reconstructed ACL injury. Conclusions: There is merit in using indirect VT as a rehabilitation device because no adverse effects have been associated with its use in research, clinical, or physical therapy. Vibration therapy has the potential to complement existing rehabilitation practices because of its ease and time efficient application. However, current research is limited and the comparison of VT protocols and study designs leaves the magnitude of adaptations and the mechanism of improvements in some VT studies uncertain. Therefore, additional studies are required to ascertain the optimal range for vibration frequency and duration, which will provide a better understanding of its mechanism and its contribution as a legitimate modality in the physical therapy field.

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Effects of Age and ACL Reconstruction on Quadriceps Gamma Loop Function

Cited by 43 publications

References 21 publications

Mechanisms of quadriceps muscle weakness in knee joint osteoarthritis: the effects of prolonged vibration on torque and muscle activation in osteoarthritic and healthy control subjects

Mechanisms of quadriceps muscle weakness in knee joint osteoarthritis: the effects of prolonged vibration on torque and muscle activation in osteoarthritic and healthy control subjects

Effect of haemarthrosis on the rehabilitation of anterior cruciate ligament reconstruction- single bundle versus double bundle

Good vibrations? – The use of vibration therapy for exercise recovery, injury prevention and rehabilitation

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