Hydrotherapy and rehabilitation in animals
Hydrotherapy in dogs: what it is, its indications, and what the evidence says about rehabilitation, osteoarthritis and neurological recovery.
Short & honest
Hydrotherapy — particularly the underwater treadmill — has moderate evidence (grade B) for postoperative recovery and osteoarthritis in dogs; single high-quality RCTs are still lacking, but existing studies are positive.
Veterinary review not yet completed
This page is awaiting review by a registered veterinary surgeon. Until then, treat the text as education based on the sources listed — not as a verified veterinary judgement.
What is hydrotherapy?
Hydrotherapy uses the properties of water — specifically buoyancy and water pressure — to enable therapeutic exercises with minimal loading of joints and tissues. In dogs, two main forms are applied:
- Underwater treadmill: the dog walks on a treadmill in a water tank; the water level determines how much body weight the limbs bear.
- Swimming therapy: free swimming in a tub or pool, where the limbs bear almost no weight.
Both forms fall within veterinary rehabilitation medicine. Certified therapists (such as CCRP) determine the indication and establish protocols.
What is it used for?
Hydrotherapy is most commonly applied for:
- Postoperative recovery — particularly after surgery for cranial cruciate ligament (CCL/TPLO/TTA). The goal is to maintain muscle mass and restore mobility while the surgical wound heals [1].
- Osteoarthritis — unloading affected joints enables pain-free movement and helps maintain muscle function [2].
- Neurological recovery — in intervertebral disc disease (IVDD), water supports controlled movement without overloading the spinal canal.
- Various orthopaedic conditions — hip and elbow dysplasia, fracture recovery and joint replacement.
What does the evidence say?
| Application | Evidence |
|---|---|
| Postoperative CCL recovery | Positive in systematic review; multimodal programme (including underwater treadmill) more effective than rest alone [1] |
| Osteoarthritis | Supportive; long-term studies are still lacking [2] |
| IVDD / neurological | Limited but promising; part of recognised protocols |
| Kinematics (water level / incline) | Well documented; higher water level increases stifle flexion; incline in water is safe for spinal patients [3] |
The systematic review of postoperative rehabilitation after cruciate ligament surgery [1] found that programmes with an underwater treadmill score better than no rehabilitation, but individual randomised controlled trials (RCTs) with high-quality design are still lacking. This places hydrotherapy at evidence grade B — reasonable evidence, not conclusive evidence.
An important detail from kinematic research [3]: the water level strongly influences biomechanics. A therapist adjusts this to the treatment goal. Incline exercises in water have also proven safe in spinal patients.
Combination with other interventions
Hydrotherapy works best as part of a broader rehabilitation plan. Recommended combinations:
- Home exercise programme for continuity between sessions
- Weight management — excess weight structurally increases joint loading [2]
- Pain management in osteoarthritis, in consultation with the veterinary surgeon
Hydrotherapy as a sole intervention is less studied than hydrotherapy as part of multimodal rehabilitation.
Practical considerations
A recognised hydrotherapist establishes the protocol and adjusts water level, speed and session duration to the animal's condition. After every session, proper drying and skin control are important. If a dog walks clearly worse after a session than before, this is a signal to reconsider the protocol.
Why this verdict?
A 2022 systematic review found positive effects of multimodal rehabilitation programmes including the underwater treadmill after cruciate ligament surgery, but individual high-quality RCTs are lacking [1]. Narrative reviews support application in osteoarthritis and neurological recovery, although long-term data remain limited [2]. Kinematic studies confirm the biomechanical mechanisms of action [3].
Legal status (Netherlands)
In the Netherlands, veterinary hydrotherapy may only be performed under the responsibility of or on the instruction of a veterinary surgeon. Certified animal physiotherapists (e.g. CCRP) generally work in collaboration with the treating veterinary surgeon.
Sources
- [1] Systematic review of postoperative rehabilitation interventions after cranial cruciate ligament surgery in dogs. Veterinary Surgery / PMC, 2022. Systematic review doi:10.1111/vsu.13755
- [2] Physiotherapeutic Strategies and Their Current Evidence for Canine Osteoarthritis. Veterinary Sciences / PMC, 2022. Narrative review doi:10.3390/vetsci10010002
- [3] A study using a canine hydrotherapy treadmill at five different conditions to kinematically assess range of motion of the thoracolumbar spine in dogs. Veterinary Medicine and Science / PMC, 2022. Narrative review doi:10.1002/vms3.1067