Shoe inserts and orthotics for sport and physical activities

Abstract

The purposes of this paper were to discuss the perceived benefits of inserts and orthotics for sport activities and to propose a new concept for inserts and orthotics. There is evidence that inserts or orthotics reduce or prevent movement-related injuries. However, there is limited knowledge about the specific functioning an orthotic or insert provides. The same orthotic or insert is often proposed for different problems. Changes in skeletal movement due to inserts or orthotics seem to be small and not systematic. Based on the results of a study using bone pins, one may question the idea that a major function of orthotics or inserts consists in aligning the skeleton. Impact cushioning with shoe inserts or orthotics is typically below 10%. Such small reductions might not be important for injury reduction. It has been suggested that changes in material properties might produce adjustments in the muscular response of the locomotor system. The foot has various sensors to detect input signals with subject specific thresholds. Subjects with similar sensitivity threshold levels seem to respond in their movement pattern in a similar way. Comfort is an important variable. From a biomechanical point of view, comfort may be related to fit, additional stabilizing muscle work, fatigue, and damping of soft tissue vibrations. Based on the presented evidence, the concept of minimizing muscle work is proposed when using orthotics or inserts. A force signal acts as an input variable on the shoe. The shoe sole acts as a first filter, the insert or orthotic as a second filter, the plantar surface of the foot as a third filter for the force input signal. The filtered information is transferred to the central nervous system that provides a subject specific dynamic response. The subject performs the movement for the task at hand. For a given movement task, the skeleton has a preferred path. If an intervention supports/counteracts the preferred movement path, muscle activity can/must be reduced/increased. Based on this concept, an optimal insert or orthotic would reduce muscle activity, feel comfortable, and should increase performance.

Bilateral Rearfoot Asymmetry and Anterior Knee Pain Syndrome

“…Indeed, depending on the study cited, effective relief in orthotics users ranges from 56% to 96%. 20,31 Orthotics prescribed for the wrong purposes may lead to some relief from symptoms. However, they represent neither a satisfactory time-nor costeffective method of treatment.…”

“…Similarly, others 20 have suggested that there is no evidence to support that the placement of the rearfoot in a neutral position is advantageous. More recently Nigg and coauthors 31 noted that orthotics led to significant but small reductions (2°-3°) in total foot eversion and subsequently concluded that foot and ankle alignment did not seem to be a predictor of increased susceptibility for movement-related injuries to the lower extremity.…”

Comprehensive elements of a physiotherapy exercise programme in haemophilia – a global perspective

“…According to Heijnen [82] and Querol [83] the use of various orthoses and footwear adaptations is commonplace in haemophilia. Functional foot orthoses (FFOÕs) have been shown to reduce pain and disability in haemophilic subjects [84], although how they achieve their effect is a matter of debate [85][86][87][88][89]. It is possible that this occurs via a direct affect on the somatosensory system [85], with the impact of the externally applied orthoses or modified footwear the mechanical components are illustrated with the green and red backgrounds; the neural components are illustrated with the purple and orange backgrounds.…”

Fatores associados à adesão ao uso de palmilhas biomecânicas

“…Basford et al 11 investigaram fatores que poderiam contribuir para a aceitação de uma órtese para membro superior e concluíram que, mesmo produzindo efeitos benéficos, o uso da órtese é descartado se ela for desconfortável. Como demonstrado em estudos prévios 21,22 , os indivíduos podem ter experimentado algum fator gerador de desconforto, levando a não-adesão, tais como: fatores intrínsecos da palmilha (comprimento e/ou largura incorretos e áreas de grande compressão no arco do pé) ou fatores biomecânicos (excesso de trabalho muscular para conter vibrações decorrentes do impacto ou para proporcionar estabilização -gerando fadiga). Segundo relatos dos pacientes, um fator importante gerador de desconforto refere-se ao grande volume ocupado pela palmilha dentro do calçado, deixando-o apertado.…”