Aquatic physical therapy has been used for thousands of years to aid in the healing process of injured limbs. Initially it was used more as a passive modality but has evolved into an excellent intervention technique since we began to understand and use the unique properties of water.

The benefits of water are numerous and people of all ages can benefit, from the elderly patient with decreased balance and strength to the elite athlete who wants to stay conditioned despite an injury. Aquatic physical therapists incorporate individual assessment, evidence-based practice and clinical reasoning to develop an appropriate treatment program. Treatment in the water, when used by a qualified physical therapist, can provide the patient with the capability to reach functional goals that a land-based program may not provide.

Uncovering the Properties of Water

The properties of water, including buoyancy and resistance, improve interventions for patients of most ages who present with musculoskeletal, neuromuscular, cardiovascular, pulmonary and integumentary disorders or conditions. Aquatic physical therapy interventions provide the following benefits:

• Promotes early range of motion;

• Allows for early initiation of gait training in a low-impact environment;

• Improves function;

• Replicates the biomechanics of land-based movements;

• Improves cardiovascular endurance;

• Increases flexibility;

• Improves muscle tone;

• Increases healing of injured tissue;

• Reduces blood-pressure levels;

• Reduces joint stiffness;

• Improves balance, coordination and agility;

• Improves body mechanics and postural stabilization;

• Promotes relaxation.

The distinct properties of water can be used to develop a patient's treatment program as well as to assist healing and exercise performance. This can make aquatic therapy an ideal choice for the rehabilitation of an injury or a post-surgical condition.

Buoyancy, an upward force exerted by a fluid on the body, is one benefit provided by water. It counteracts the effects of gravity. This property assists in supporting the weight of the patient and decreases the amount of weight-bearing through joints. It helps strengthen weakened body parts from injury, surgery, immobilization or disease.

Decreased stress and loading to joints allows patients to perform functional exercises with more ease that were otherwise painful when performed on land. Depth of the water can be adjusted depending on how much weight your patient can tolerate bearing through the affected limb or limbs. Water can relieve body weight up to 75 percent when the person is immersed up to neck level. This benefit allows a therapist to develop a patient's mobility without placing stress on the joints.

Progression of your patient's program can be indicated by the ability to decrease the depth of immersion. Patients can also perform exercises in a horizontal position through the support of the water until they are strong enough to progress to using buoyancy for resistive training.

Another unique property of water is viscosity, defined as a fluid's internal resistance to flow, or its friction. Water is denser than air and provides greater resistance to movement. The more surface area that you present in the direction of the movement, the more resistance you create, and the more force needed to overcome that resistance. This property of water provides a great source of resistance when developing a patient's strength and works simultaneously on muscular balance, coordination, body alignment and posture.

Decreased stress as provided by buoyancy and increased resistance due to the viscosity, allows a patient to strengthen muscles in a functional manner that they could not perform on land. The density of water also slows movement and supports body positions that would otherwise be unstable on land. This property helps minimize risk of injury. Weights are not needed, but the addition of equipment including foam cuffs and paddles can increase the resistance further when advancing the patient's program.

Aquatic therapy also uses hydrostatic pressure to decrease swelling and improve proprioception. Hydrostatic pressure is the force exerted by water on the immersed object and is proportional to the depth of the water. The perpendicular force produced by hydrostatic pressure provides the patient with awareness of joint position. Increasing proprioceptive awareness is important for patients who sprained a joint or demonstrate poor balance. Agitating water creates turbulence, which can be used for both static and dynamic balance training.

Increasing the speed or movement of an exercise within the water can increase the challenge to the patient because more resistance is met. Swelling in joints and soft tissue after injury or from arthritis is reduced by the compression provided by the weight of the water. This constant pressure also helps lower a patient's pain level and improve circulation. In addition, hydrostatic pressure provides resistance to chest wall expansion, which can help increase the patient's vital capacity.

The temperature of the water can also be therapeutic. Warm water helps relax muscles, dilatevessels and increase blood flow to injured areas. Patients who demonstrate significant muscular guarding can benefit from warm water to decrease muscle spasm, relax tense muscles, relieve pain and thus increase range of motion. Increased blood flow from vasodilatation delivers oxygen and nutrients to the affected limb and/or joint as well as removes cell wastes.

Cooler temperatures can be used to produce vasoconstriction, which slows circulation, reducing inflammation, muscle spasms and pain. There are some general guidelines to follow when deciding the temperature of the water for your patient: 82 to 88 degrees for more active patients and patients with MS, 88 to 92 degrees for less active patients such as those with arthritis, and 92 to 96 degrees for less active patients with hypertonicity/spasticity issues.

Improved Health and Self-Esteem

Aquatic therapy not only has great potential for improving ailments but also promotes good health. Physiological benefits include improved mood, enhanced self-esteem and body image and decreased anxiety and depression.

Individuals who may benefit from this include those with multiple sclerosis, cystic fibrosis, arthritis, orthopedic impairments, cerebral palsy and asthma. However, aquatic therapy is not for everyone, including those who have fevers, infections or bowel/bladder incontinence.

Aquatic physical therapy can be used for a variety of diagnoses. In addition to the previously mentioned circumstances, aquatic therapy may also benefit people with fibromyalgia or RSD, overweight patients or athletes with a stress fractures.

Patients with fibromyalgia can become dependent on long-term physical therapy with the use of passive techniques including massage, electrical stimulation and heat. Aerobic exercise is important for this patient population since they tend to be deconditioned. Performing regular aquatic exercise can break the pattern of pain, fatigue and decreased motivation.

Overweight patients benefit from performing therapeutic exercises in water due to the benefits of buoyancy, decreasing stress to the joints as well as decreasing the risk of injury. Moderate exercise in the water for 10 minutes can burn up to 100 calories.

Many athletic injuries are based on overuse of muscles, tendons and joints, for which rest is recommended. However, aquatic therapy can also be a useful tool, allowing the athlete's injury time to recover while using the properties of water to challenge balance, gain neuromuscular input and maintain cardiovascular fitness.

The next time you perform an evaluation, ask yourself these questions: Can this patient tolerate a typical land-based physical therapy program? Would this patient progress faster in the water? Has this patient failed previous land-based physical therapy programs?

If you answered yes to any or all of these questions, your patient may benefit from starting his program in the protective, joint-sparing environment of the water. But remember, as physical therapists, our goal is to get patients back to their functional activities. So when preparing an aquatic program, long-term goals need to include progression back to land.

Erica Gerlach is the clinic manager of Excel Physical Therapy and Fitness in Krewstown, PA. In addition to aquatic therapy, her interests lie in orthopedic injuries and sports medicine as well as treating patients with pain originating from the spine. This interest has led her to pursue certification in mechanical diagnosis and therapy, also known as the McKenzie Method.