Intraarticular pressure distribution in the talocrural joint is related to lower leg muscle forces

A systematic review of the effect of footwear, foot orthoses and taping on lower limb muscle activity during walking and running

BACKGROUND

External devices are used to manage musculoskeletal pathologies by altering loading of the foot, which could result in altered muscle activity that could have therapeutic benefits.

OBJECTIVES

To establish if evidence exists that footwear, foot orthoses and taping alter lower limb muscle activity during walking and running.

STUDY DESIGN

Systematic literature review.

METHODS

CINAHL, MEDLINE, ScienceDirect, SPORTDiscus and Web of Science databases were searched. Quality assessment was performed using guidelines for assessing healthcare interventions and electromyography methodology.

RESULTS

Thirty-one studies were included: 22 related to footwear, eight foot orthoses and one taping. In walking, (1) rocker footwear apparently decreases tibialis anterior activity and increases triceps surae activity, (2) orthoses could decrease activity of tibialis posterior and increase activity of peroneus longus and (3) other footwear and taping effects are unclear.

CONCLUSION

Modifications in shoe or orthosis design in the sagittal or frontal plane can alter activation in walking of muscles acting primarily in these planes. Adequately powered research with kinematic and kinetic data is needed to explain the presence/absence of changes in muscle activation with external devices.

CLINICAL RELEVANCE

This review provides some evidence that foot orthoses can reduce tibialis posterior activity, potentially benefitting specific musculoskeletal pathologies.

Influence of calibration method and material on the accuracy of stress distribution measurement systems

Biomechanical analyses of the stress distribution and the force transfer in the human knee are essential to better understand the aetiology of joint diseases. Accuracy studies of commonly used capacitive or resistive-based stress distribution measurement systems have led to severe problems caused by an inaccurate experimental setup. For instance, in one study, overestimations of the measured forces in the sensor's centre were reported. Therefore, the primary aim of this study was to investigate the ability of capacitive and resistive-based sensors to measure forces in a homogenous pressure environment and the secondary goal was to analyse the influence of different calibration materials on the measurement accuracy. A Novel pressure vessel and metal indenters covered with different rubber materials were used in combination with a material testing machine to load the sensors. Four different linearly increasing nominal forces (925-3670 N) were applied and the deviations between the nominal and the measured forces were calculated. The capacitive measurement system showed errors between 1% and 7% in the homogenous pressure environment, whereas the errors of the resistive system were found to vary between 4% and 17%. The influence of the calibration material was observed to be greater for the resistive sensors (1-179%) than for the capacitive sensors (0.5-25%). In conclusion, it can be stated that - for the pressure measurement systems compared in this article - the capacitive one is less sensitive to the calibration method and the calibration material than the resistive system.

Extrinsic Muscle Forces Affect Ankle Loading Before and After Total Ankle Arthroplasty

BACKGROUND

Joint loading conditions have an effect on the development and management of ankle osteoarthritis and on aseptic loosening after total ankle arthroplasty (TAA). Apart from body weight, compressive forces induced by muscle action may affect joint loading. However, few studies have evaluated the influence of individual muscles on the intraarticular pressure distribution in the ankle.

QUESTION/PURPOSES

The purpose of this study was to measure intraarticular pressure distribution and, in particular, (1) to quantify the effect of individual muscle action on peak-pressure magnitude; and (2) to identify the location of the center of pressure in the weightbearing native ankles and ankles that had TAA.

METHODS

Peak pressure and intraarticular center of pressure were quantified during force alterations of four muscle groups (peronei, tibialis anterior, tibialis posterior, and triceps surae) in 10 cadaveric feet. The pressure was measured with a pressure sensitive array before and after implantation of a three-component mobile-bearing TAA prosthesis. Linear mixed-effects models were calculated and the y-intercept (b0) and the slope (b1) of the regression were used to quantify the size of the effect.

RESULTS

Mean maximum peak pressures of 2 MPa (± 2.6 MPa) and 6.2 MPa (± 3.6 MPa) were measured for the native and TAA joint respectively. The triceps surae greatly affect the magnitude of peak pressure in the native ankle (slope b1 = 0.174; p = 0.001) and TAA joint (slope b1 = 0.416; p = 0.001). Furthermore, the force of most muscles caused a posterior and lateral shift of the center of pressure in both conditions.

CONCLUSIONS

Our results suggest that muscle force production has the potential to alter the pressure distribution in the native ankles and those with and TAA.

CLINICAL RELEVANCE

Our study results help us to understand the effect of muscle forces on joint loading conditions which could be used in muscle training strategies and the design of better prosthetic components. Physical therapy or guided exercises may provide the potential to relieve areas in the joint that show signs of early osteoarthritis or reduce the contact stress on prosthetic components, potentially reducing the risk of TAA failure attributable to wear.

Insertion of a pressure sensing arrayminimally affects hindfoot bone kinematics

BACKGROUND

Understanding the development of ankle osteoarthritis (OA) is of high importance and interest; however its causality is poorly understood and several links to joint loading conditions have been made. One way of quantifying joint loading conditions is by measuring the intra-articular pressure distribution during gait simulations performed by in-vitro experimental set-ups. However the effect of inserting a pressure sensing array in the ankle joint could potentially disturb the proper kinematics and therefore the loading conditions.

METHODS

In this study, we performed in-vitro gait simulations in 7 cadaveric feet, before and after inserting a pressure sensing array and quantified the effect on the joints range of motion (ROM). The gait was simulated with a stance phase duration of one second using a custom build cadaveric gait simulator (CGS).

RESULTS

The results show a limited effect in the ROM for all the joints of the hind foot, not exceeding the variability observed in specimens without a sensor. However, no consistent direction (increase/decrease) can be observed.

CONCLUSION

The results suggest that even though the effect of inserting a pressure sensing array is minimal, it needs to be evaluated against the demands/requirements of the application.

Fetal development of ligaments around the tarsal bones with special reference to contribution of muscles

Through a histological examination of eight mid-term human fetuses (10-15 weeks) and seven late-stage fetuses (30-34 weeks), we attempted to determine how and when fetal ligaments around the tarsal bones form the regular arrangement seen in adults. Ligaments along the dorsal aspect of the tarsal bones developed early as an elongation of the perichondrium, in contrast to the late development of the plantar-sided ligaments. In contrast, a distal elongation of the tibialis posterior tendon was a limited plantar ligament in the early stage; finally, it extended from the navicular, ran obliquely to cross the dorsal side of the fibularis longus tendon, and inserted to the lateral cuneiform and fourth metatarsal. In the late stage, the adductor hallucis muscle origin provided multiple ligamentous structures along the cuneiforms and metatarsals. The tarsal sinus contained multiple fibrous bundles (possibly, the putative interosseous talocalcanean ligaments) that were derived from (1) insertion tendons of the extensor digitorus brevis muscle and (2) the fibrous sheath of the extensor digitorus longus tendon. The aponeurotic origin of the quadratus plantae muscle seemed to contribute to formation of the long plantar ligament. Therefore, tarsal ligaments appeared likely to develop from the long tendons, their fibrous sheaths and aponeuroses and intramuscular tendons of the proper foot muscles. Under in utero conditions with little or no stress from the plantar side of the foot, the muscle-associated connective tissue seems to play a crucial role in providing a regular arrangement of the ligaments in accordance with tensile stress from muscle contraction.

The effect of neutral-cushioned running shoes on the intra-articular force in the haemophilic ankle

BACKGROUND

The ankle continues to be one of the most affected joints in the haemophilia patient, and as cartilage damage progresses, the joint can feel unstable, painful and stiff. Anecdotally, patients often report that sports trainers can improve their pain and daily function, however the actual mechanism for this remains unclear.

METHODS

Nine patients with ankle haemarthropathy and three controls were examined using 'CODAmotion' analysis and a force plate. Kinematic and kinetic variables of the hip, knee and ankle were recorded. Data was imported from CODA to Excel, where a programme using 2D modelling of the ankle joint forces was employed. This calculated intra-articular force from heel strike to toe-off.

FINDINGS

The haemophilia group at midstance showed an increase in intra-articular force in the ankle when wearing the trainer compared to the shoe (P=<0.05). Overall the haemophilia cohort had an increased joint force in both the trainers and shoes, compared to controls.

INTERPRETATION

The type of footwear worn by individuals with ankle arthropathy has a significant effect on the amount of force acting at the joint surface. Sports shoes, in providing better comfort and foot support, may facilitate an increased muscular activity around the ankle and therefore improved dynamic joint stability, accounting for why some patients with ankle arthropathy report less pain. Further research is needed to establish levels of acceptable force and the combined effects of orthotics and footwear.

Biomechanical consequences of a posterior root tear of the lateral meniscus: stabilizing effect of the meniscofemoral ligament

PURPOSE

The purpose of this study was to evaluate the effects of different types of lateral meniscus root tears in terms of tibiofemoral contact stress.

METHODS

Ten porcine knees each underwent five different testing conditions with the menisci intact, a simulated lateral posterior root tear with and without cutting the meniscofemoral ligament and with an artificial tear of the posterior root of the medial meniscus. Biomechanical testing was performed at 30° of flexion with an axial load of 100 N. A pressure sensor (st Sensor Type S2042, Novel, Munich) was used to measure the tibiofemoral contact area and the tibiofemoral contact pressure. Data were analyzed to assess the differences in contact area and tibiofemoral peak contact pressure among the five meniscal conditions.

RESULTS

There was no significant difference in mean contact pressure between the state with the menisci intact and an isolated posterior root tear of the lateral meniscus. In case of a root tear and a tear of the meniscofemoral ligament, the contact area decreased in comparison with the intact state of the menisci. After additional cutting of the meniscofemoral ligament, the tibiofemoral contact pressure was significantly higher in comparison with the intact state and the avulsion injury. In the medial compartment, joint compression forces were significantly increased in comparison with the intact state after cutting the posterior root of the medial meniscus (P < 0.05).

CONCLUSIONS

The consequence of a medial meniscus root tear is well known and was verified by this analysis. The results of the present study show that the biomechanical consequences of a lateral meniscus root tear depend on the state of the meniscofemoral ligament. An increase in tibiofemoral contact pressure is only to be expected in combined injuries of the meniscus root and the meniscofemoral ligaments.

CLINICAL RELEVANCE

Posterior lateral meniscus root tear might have a better prognosis in terms of the development of osteoarthritis when the meniscofemoral ligament is intact.

Arthroscopic fixation of matrix-associated autologous chondrocyte implantation: importance of fixation pin angle on joint compression forces

PURPOSE

The aim of the study was to investigate the effect of pin fixation perpendicular and 30° tilted to the matrix surface on the joint compression forces.

METHODS

In a porcine knee model, joint compression forces were recorded with a digital pressure sensor above the medial meniscus and with axial compression of 100 N by use of a material testing machine. The forces were recorded for an intact femoral condyle, as well as a standardized cartilage defect of 25 × 20 mm, after matrix-associated autologous chondrocyte implantation (m-ACI) (BioSeed C; Biotissue Technologies, Freiburg, Germany), fixed by use of a conventional suture technique and pin fixation with a biodegradable pin perpendicular and 30° tilted to the matrix surface.

RESULTS

In knees with cartilage defects, the peak compression forces (mean, 824 kPa) were significantly increased compared with the intact knee joint (564 kPa). After m-ACI implantation with a chondral suture (581.3 kPa) and perpendicular pin fixation, the joint compression forces of the cartilage defect were significantly decreased (630.7 kPa). There were no significant differences compared with the intact knee. After 30° tilted pin insertion, mean joint compression forces were significantly increased (1,740 kPa).

CONCLUSIONS

This study shows that after chondral suture and perpendicular pin fixation, there are no increased compression forces in the knee joint in comparison to an intact knee. Thirty degree tilted pin insertion contributes to increased joint compression forces.

CLINICAL RELEVANCE

A tilted insertion during pin fixation in m-ACI should be avoided because it may lead to increased joint compression forces, especially after cartilage defect lesions on the tibial side.

The relation between geometry and function of the ankle joint complex: a biomechanical review

This review deals with the relation between the anatomy and function of the ankle joint complex. The questions addressed are how high do the forces in the ankle joint get, where can the joints go (range of motion) and where do they go during walking and running. Finally the role of the ligaments and the articular surfaces is discussed, i.e. how does it happen. The magnitude of the loads on the ankle joint complex are primarily determined by muscle activity and can be as high as four times the body weight during walking. For the maximal range of motion, plantar and dorsiflexion occurs in the talocrural joint and marginally at the subtalar joint. In-eversion takes place at both levels. The functional range of motion is well within the limits of the maximal range of motion. The ligaments do not contribute to the forces for the functional range of motion but determine the maximal range of motion together with the articular surfaces. The geometry of the articular surfaces primarily determines the kinematics. Clinical studies must include these anatomical aspects to better understand the mechanism of injury, recovery, and interventions. Models can elucidate the mechanism by which the anatomy relates to the function. The relation between the anatomy and mechanical properties of the joint structures and joint function should be considered for diagnosis and treatment of ankle joint pathology.

Changes in contact area characteristics of the ankle after a cartilage biopsy at the postero-medial rim of the talar dome

OBJECTIVE

Study the changes in local and generalized biomechanical characteristics of the ankle joint, associated with a well defined cartilage biopsy at the postero-medial rim of the talar dome, to evaluate its safety.

METHODS

Ten cadaver ankles were (sub-) physiologically loaded pre- and post-biopsy; in neutral position, 10 degrees of plantar-flexion (PF) and 10 degrees of dorsi-flexion (DF). Fuji film was used as transducer. Qualitatively, the coverage of the biopsy by the tibial plafond, and changes in the shape of the footprint were analyzed. Quantitatively, the pressure profile plot, normalized-tibio-talar contact area and the centroid position of pressure were examined. Results were reported as a mean for all specimens, and as individual values for every single specimen as well.

RESULTS

Mean results did not show significant changes, but those of some single specimens did. The majority of those changes were in PF. Some occurred in N, and besides two exceptions none occurred in DF. Two specimens did not show any change. One specimen showed an isolated quantitative change. Seven specimens showed both qualitative and quantitative changes. However, all changes were of low-magnitude and contact stresses did not show any rebound effect.

CONCLUSIONS

Although biopsies at the postero-medial rim of the talar dome did not induce on average significant changes in quantitative contact characteristics, few specimens did show some alterations. Currently, the investigated biopsy site seems safe, but long term follow-up studies in patients are needed for confirmation.