Osteogenesis Imperfecta (O.I.) is a particularly individual condition. Because O.I. is a general disorder of connective tissue, it can manifest itself in different ways in different people. Although O.I. is firstly associated with an increased risk of fractures, the disorder may also be responsible for poor posture, increased joint laxity and instability, musculoskeletal pain and injury, Dentinogenesis imperfecta, hearing problems, cardiac and respiratory disorders, bone deformities, underdeveloped motor skills and an increased risk of falling. With such a wide array of disorders associated with Osteogenesis Imperfecta and such an individualized manifestation of the condition, exercise professionals must program according to each client's strengths and weaknesses.
The role of the exercise professional is also to bridge the gap between initial recovery phases, following fractures and the long term management of the condition. The rehabilitation, management and treatment of musculoskeletal fractures associated with the condition and indeed of the condition in general can be divided into three distinct phases or progressions:
- Fracture Recovery
- Mobility and Range of Motion Training
- Balance and Proprioception Training
- Corrective Exercise Training (Posture and Biomechanics)
- Resistance Training (to improve musculoskeletal strength and function)
- Cardiovascular Training (to improve respiratory and cardiac function)
The key to effective treatment and efficient recovery from fractures is a swift return to normal function. Limb immobilization following fracture should be kept to a minimum. It is also important to ensure that even when one limb is fractured, the joints of the rest of the body are still trained appropriately. Water-based exercise is commonly recommended for most people with O.I., because mobility and range of motion can still be trained with a significantly reduced risk of repeated fracture or inhibiting fracture repair. Exercise training should commence as early as possible following fracture as immobilization will reduce muscle strength, joint mobility and bone strength.
Progressive and sometimes severe postural abnormalities are associated with Osteogenesis Imperfecta. These abnormalities may inhibit normal function and even compromise the ability of the pulmonary system to work properly. The curvature of the spine is the result of stresses placed on the vertebrae by the attached musculature. In people with O.I., because their bones are not formed properly, they are at risk of the extraordinary effects their muscles have on the skeleton. Indeed, some fractures may occur purely because of the stress imparted on the long bones of the body by the associated muscles. This is one reason why it is particularly important to determine as much about the severity of your client’s condition as possible, utilizing information gathered from the individual and his or her other healthcare providers.
While improving joint integrity and bone mass are the ideals of the training program, the emphasis should be on incorporating exercises to improve daily function. This does not just involve programming to improve joints and bones, but it also requires an analytical and targeted approach to deal with all of the individual’s conditions in turn.
The benefits of weight bearing, functional cardiovascular exercise (i.e., walking) should not be underestimated. In individuals who are able to walk, this form of exercise may promote (or prevent decreases of) range of motion as well as improve cardiac and respiratory function and increase bone strength and mass. Walking can still be recommended for individuals who use walking sticks and frames, but additional care should be taken to promote balance and reduce the risk of falling.
Annual measurements of bone mineral density (BMD) are useful for assessing the productivity of an exercise intervention and also checking on the current status of the condition. Dual-Energy X-ray Absorptiometry (DEXA) is a quick and non intrusive means of measuring BMD and causes less radiation than standard X-ray machines. There is no merit in measuring BMD more than once a year as bone density is unlikely to change to a detectable level within this time. It is also important to keep in mind there may be differences in measurements when using different machines.
Bone mineral measurements can only give an inference of bone strength, as bone may become much stronger than relatively small gains in BMD would suggest. This may be partly because bone density is increased in the weakest areas or where mechanical stresses have been greatest.
Because fractures are so commonplace in many people with O.I., there is a huge opportunity for bone strength and motor skills to be reduced by immobilization. Aquatic exercise is a medium whereby the exercise professional can restore or develop mobility and some motor function and even place some mild stress on the bones that may not be possible outside of that environment. Furthermore, in returning to training for activities of daily living, the individual may be limited to the point where they require modifications within their homes, or they will need to learn to make use of specific assistive tools and devices for particular tasks. This is the point when it is useful to seek out an occupational therapist experienced with O.I. who will be able to visit the person’s home and determine how best to protect and promote independence with the variety of tools available.
During the progressive phases of the exercise micro- and macrocycles, it is likely there will be a need for reducing support and increasing resistive and weight bearing movements. From an initial or base, aquatic phase, progression may incorporate partial to complete weight earing, with the exercise professional using either manual assistance or manual resistance, accordingly. Range of motion and other functional training should also improve the individual’s ability to move freely when in lying, sitting and standing postures. Although manual resistance will in most cases be the safest form of resistance, it is importance to avoid excessive pushing, pulling or twisting forces. "Excessive" is therefore a specific term for each individual, and while recklessness is inexcusable in any exercise professional, should a fracture occur (even despite a gradual and progressive program), it is important to re-evaluate the program and continue accordingly as soon as possible. This is a particularly important justification for communicating with other medical professionals and ensuring the client and their family understand and accept what you are working to achieve.
One must simply accept that bones are often vastly more susceptible to fracture and that certain resistive movements, such as passive rotations of parts of the body, are particularly likely to lead to damage and must be avoided. In addition, some specific exercises are contraindicated for persons with O.I., such as bridging, or those that involve hip flexion or diagonal trunk rotation. Muscles pull on their attachments, leading to bowing of some of the long bones, and otherwise insignificant forces within those muscles may lead to fractures in someone with O.I. If supporting someone so that they can perform standing exercises when they would normally lack the strength, it is important to ensure that their legs do not crumple underneath them, and if necessary employ the help of a colleague for some exercises.
As an exercise professional, you have the ability to train your clients in such a way as to improve their ability to perform activities of daily living and to reduce the apparent severity of their condition. This involves a mature and intelligent approach, whereby you are one member of a team composed of various medical professionals as well as the patient or client themselves and their friends and family members. All of these people are likely to be far more accustomed to managing O.I., and their assistance and advice will be invaluable to you.