An orthosis increases the freedom of movement and independence due to its supportive function and conducive effect on health, but for what pathological target groups might this be applicable? In this series of articles, Spentys offers an introduction to common injuries utilizing the correcting, easing, or immobilizing characteristics of externally applied medical devices.

This series's first article will cover the common injuries and disturbances in the support and musculoskeletal system, the general orthopedic disorders.

As early as the fifth week of fetal life, extremity nodes start to form and within a week from then, hand and foot plate segments can be distinguished. Disturbances of normal fetal growth have implications at the developmental level and can lead to congenital deviations.

Once born, a baby's musculoskeletal system is not complementary to that of an adult. The physis is still expanding, the epiphysis starts ossifying, and the diaphysis is more elastic, leading to different fractures. Life itself has an impact on the various possible abnormalities, growth, overuse, infections, injuries, and fractures, all potential orthopedic etiologies.

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From caudal to cranial. An overview of the most prevalent anomalies.

Lower Limb

Although the name ‘orthosis’ tends to push people’s thinking pattern in complicated directions, an orthosis does not have to be a very complex device. A simple rigid insole providing shock absorption and correction to patients with flexible foot deformities is already meeting the requirements. More severe foot deformities as pes -varus, -valgus, -abductus or -adductus can be corrected with the aid of supra malleolar orthosis. Toe distortions as extension or hallux valgus are commonly prevented with a night orthosis.

Ankle-foot orthoses are mainly used to substitute impaired muscle performance and will be more elaborately discussed in the third article in this series, covering the neuromuscular system. The ankle is a regularly used dynamic joint with multiple possible contraction sites.

Thickness and rigidness of the immobilizing orthosis depend on the specific situation and expert’s opinion.

When ankle-foot orthoses do not provide sufficient stability during stance and the center of support should be raised, the knee-ankle-foot orthosis offers a possible solution. Again, this is more frequent in neuromuscular diseases but patients with general knee joint damages benefit as well from this type of orthosis. Lower limb alignment due to growth deformities can be corrected with locked, or free moving knee joint orthoses.

Strains, bursitis, dislocations, and fractures can happen to all the above, but a hip fracture or displacement is noteworthy on its own. Twenty percent of the patients die within a year and only one-fourth of the patients fully recovers. The majority of accidents are elderly people fracturing their hip through a simple fall. Immobilizing the hip will not be the best treatment, but an integrated approach in which a rigid orthosis and brace are applied as post-operative support has proven to be very effective.

Trunk

The prevalence of moderate scoliosis is three percent in a normal population, but it is substantially higher for profound and multiple disabled persons. Treatment procedure depends on the curvature of the spine, the so-called ‘Cobb’s angle’. If this angle exceeds 25 degrees an external force in the form of an orthosis will be applied to modify the spinal growth. Multiple correcting types exist varying in size, material, etc. but most importantly varying in pressure points to optimize corrective function. Lordosis or kyphosis correcting orthosis rely on the same principles but adjust the patient’s growth direction in the sagittal plane.
Immobilizing orthoses are also implemented post-surgical, they can consist of one (Boston overlap) or two shelves (Bivalve) depending on the trade-off between comfort and fixation.

Upper Limb

Upper limb orthoses differ from the lower limb and trunk orthoses; the fabrics are lighter and often softer plastics since they do not have to withstand the weight-bearing conditions to keep the body upright. A distinction can be made based on the comforting, correcting or functional benefits.  

The tether thumb stabilizer and the butterfly thumb splint are two common thumb orthoses implemented to correct thumb position or used for rehabilitation purposes post-surgery. Same application strategies are seen for the hand and hand-wrist orthoses. The hand consists of the transversal carpal, transversal metacarpal, and longitudinal arch and all three are possible to manipulate with the aid of orthosis. Target groups for these types of orthosis are patients with Club hands, Swan Neck Deformity (SND), Jaccoud’s hands, etc. The etiology of SND and Jaccoud’s hands will be discussed in more detail in the second article, covering the syndromes and special diseases, in this case, arthritis.

A fracture of the radius is the most common fracture. Typical casting occurs with the aid of the single sugar-tong. Double sugar-tongs prevent the flexion-extension and pronation-supination more and are seen with slightly higher fractures in the forearm or elbow region.

Humerus fractures are treated similarly, best rehabilitation results are reached when integrating a sling, orthosis, and therapy.

Head

Positional plagiocephaly is an unusual flattening of the baby’s head. Cranial remodeling cannot be used as treatment but may be used for protection post-operation or to direct the head in the correct shape. The helmet-shaped orthosis leaves space in the area's where the head is ought to expand to remold the skull's shape.

This article does not state all the target groups benefiting from an immobilizing cast or orthosis; it briefly introduces several common orthopedic disorders. The contents of this article may not be used as a treatment prescription. They are written to offer an overall understanding of this topic. Always contact your general practitioner or doctor.

The next article in this series will cover the orthopedic disorders resulting from syndromes and various specific diseases.