Lower limb joint motion and muscle force in treadmill and over-ground exercise

Purpose. The purpose of this study is to investigate the clinical effect of lower-limb exercise, when combined with celecoxib, on pain management of patients undergoing posterior lumbar fusion surgeries. Methods. The patients undergoing posterior lumbar fusion surgeries between 01/2018 and 06/2021 were retrospectively identified, with their data collected. After surgery, some patients took celecoxib for analgesia (celecoxib group, 200 mg/day) while the others took celecoxib together with lower-limb exercise (combined group, celecoxib-200 mg/day). On postoperative days (POD) 1, 3, 7, and 14, data were collected and analyzed regarding the following items: patient satisfaction, lower-limb muscle force, lumbar JOA score (29 points), Oswestry Disability Index (ODI), and visual analog scale (VAS) score. Results. A total of 225 participants were included in this study. Specifically, 120 cases were admitted into in the celecoxib group and 105 were included in the combined group. Comparisons of baseline data did not indicate any difference between the combined group and the celecoxib group. Data analysis showed that patient satisfaction in the combined group was significantly higher than the celecoxib group on POD 3, 7, and 14, respectively (all p < 0.001 ). Moreover, the combined group had less VAS score compared with the celecoxib group on POD 3, 7, and 14, respectively (all p < 0.01 ). In addition, lower-limb muscle force in the combined group was significantly stronger than that in the celecoxib group on POD 3 and POD 7, respectively (both p < 0.01 ). Furthermore, the combined group achieved less ODI score than the celecoxib group on POD 3, 7, and 14, respectively (all p < 0.05 ). Comparisons of the lumbar JOA score did not suggest any statistical difference during the whole follow-up period. Conclusions. In conclusion, postoperative lower-limb rehabilitation exercise can help to release pain after lumbar fusion surgeries. Additionally, postoperative lower-limb exercise can facilitate the recovery of lower-limb muscle force, as well as improving patient satisfaction.

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Achilles Tendon Moment Arms Computed Using Ultrasound and Motion Analysis: In Vivo Estimates for Male Subjects

ASME 2008 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2008-193155 ◽

2008 ◽

Author(s):

Justin D. Cowder ◽

Thomas S. Buchanan ◽

Kurt T. Manal

Keyword(s):

Achilles Tendon ◽

Motion Capture ◽

Hybrid Method ◽

Lower Limb ◽

Muscle Force ◽

Average Weight ◽

Moment Arm ◽

Moment Arms ◽

Male Subjects

Accurate estimates for Achilles tendon moment arm (MA) are essential when computing gastroc-soleus force from the net plantarflexion moment. Errors in approximating the Achilles tendon MA will adversely affect the muscle force estimate. We have noted that Achilles tendon MAs reported by Maganaris [1] and others are significantly greater (> 1 cm) than values used by Delp et al. computed using SIMM [2]. It is important to note that the stature of Delp’s lower limb model was almost identical to the average weight and height of the subjects in a study by Maganaris. This led us to question which MA profiles were more anatomically meaningful. To address this, we calculated Achilles tendon MAs for 10 male subjects using a previously described method. The method combines ultrasound and video-based motion capture, and referred to as the hybrid method. Subjects in our study were chosen to ensure they were of a similar stature to those tested by Maganaris, thereby minimizing confounding effects of subject anthropometrics.

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A Computer Model Assessment of the Effect of Hindfoot Alignment on Mechanical Axis Deviation and Ankle Fractures

Foot & Ankle Orthopaedics ◽

10.1177/2473011418s00214 ◽

2018 ◽

Vol 3 (3) ◽

pp. 2473011418S0021

Author(s):

Naven Duggal ◽

Patrick Williamson ◽

Ara Nazarian

Keyword(s):

Compressive Stress ◽

Lower Limb ◽

Muscle Force ◽

Mechanical Axis ◽

Stress Fractures ◽

Biomechanical Study ◽

Lateral Malleolus ◽

Axis Deviation ◽

Pes Planus ◽

Mechanical Axis Deviation

Category: Basic Sciences/Biologics Introduction/Purpose: Conventional mechanical axis is calculated from the center of the femoral head to the center of the ankle. Mechanical axis deviation of the lower limb can be associated with a pes planus hindfoot. Malalignment of the lower limb has been shown to increase progression of osteoarthritis of the knee and ankle and decrease joint arthroplasty longevity. Clinically, a pes planus hindfoot has also been seen with patients who present with a stress fracture of the lateral malleolus. This biomechanical study aims to utilize computer modeling to evaluate the hypothesis that altered force transmission on the lateral malleolus with resultant stress fractures in a pes planus model is attributable to mechanical axis deviation. Methods: A free-body diagram of the fibula in single leg stance was generated by modeling the fibula as a uniform cylinder. It includes the axially applied load and a single evertor muscle force as an eccentric load applied to the mid-diaphysis . Previously derived relationships between body weight (BW = 667 N, 150lbs) and a) normal axial fibula load (BW*0.17) and b) muscle force (BW*0.25) were used. Fibula length (286.5 mm) and diameter (8 mm) were derived from anthropological data. Mechanical axis deviation in pes planus was simulated in two manners: 1) increased (2 and 3 times normal) axial fibula load and 2) increased evertor muscle force. The compressive stress along the length of the bone was determined through static analysis and the total applied load was compared to theoretical Euler buckling load. Results: Increasing the load on the fibula, either by increasing the axial load (Figure 1A) or the muscle load (Figure 1B), increases the maximum compressive stress below the lateral muscle origins, namely the section between the distal tibiofibular ligaments and the evertor muscles. The compressive stress for both cases was less than the compressive yield stress of cortical bone (200 MPa) and cancellous bone (100 MPa) even as the force was increased to the critical buckling value. This model serves as a first attempt to relate the spatial distribution of stress in the fibula with muscle force, axial load, and compressive stress in light of distal fibular fractures associated with pes planus. Conclusion: The importance of lower extremity mechanical axis deviation is well established in the progression of arthritis in the knee and ankle. The role of the mechanical axis in the predisposition of stress fractures around the ankle has not been evaluated in the literature. This biomechanical study represents the first attempt to understand how deviation of the mechanical axis can result in stress fractures of the lateral malleolus. Future studies including a finite element analysis will provide further information and the results of these studies may alter how clinicians treat patients with stress fractures of the fibula.

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