Guidelines and Best Practices

Minimum and Reasonable Mobility Dog Guidelines

Service/Assistance dogs providing mobility* assistance for balance and stability perform physically demanding work; we must thoughtfully consider the dog’s health and well-being to minimize any potential negative impacts on the dog’s physical and mental health. These recommendations and best practices for mobility dogs have been developed in collaboration with service dog organizations, professional  trainers, breeders, veterinarians and canine physiotherapists who specialize in orthopedic rehabilitation and sports medicine, working dog professionals, dog equipment experts, and people partnered with mobility service dogs. The goal of this collaboration is to ensure dogs are thoroughly vetted and well-suited to the demands of service dog work so they may lead long, healthy lives as service/assistance dogs.

*Mobility in this context refers to dogs that perform tasks to physically assist with balance and stability, where work includes any load-bearing activity such as guiding, pulling, counterbalance, and bracing. Bracing refers to the application of downwards pressure onto the dog’s body and is specifically a weight-bearing activity that deserves additional considerations for the dog’s safety.

Minimum Guidelines

Dogs should be physically mature, thoroughly vetted, and of adequate size before training or performing mobility-specific tasks like brace and/or harness work.

Minimum age of 18-24 months

• Epiphyseal fused (growth plates closed) and fully developed skeletal system
• Fully developed muscular system and ability to maintain mature muscle mass and strength
• Minimum age varies by dog size and breed (larger breeds need longer to mature)
• Strain and repetitive motion on underdeveloped joints, muscles and connective tissues increases the risk and severity of injury, development of osteoarthritis (a painful, degenerative disease), as well as shortens quality of work and career longevity.

Note: Full maturation happens after both skeletal and muscular development is finished. Large breeds commonly seen as working dogs are generally ready for full work at two years of age.

Recommended minimum weight and height – weight of 60 pounds (27.2 kg) and height of 22” (56 cm) at the withers

• The weight recommendation is for dogs that are fit and in excellent body condition; minimum size a general recommendation, there is no magical cutoff number
• Dogs should be appropriately sized for their human partner’s size and needs
  – larger dogs that are fit and muscular are at lower risk of strain and injury
  – smaller dogs and dogs with poor body condition may experience more wear-and-tear on their bodies, a risk factor for OA, as well as injury.

Health checks – Radiographs/X-rays performed on hips and low back, elbows and shoulders

• Rule out orthopedic issues and dysplasia that may cause injury, pain and/or limit the dog’s ability to work
• OFA(i) or PennHIP(ii) reviews are strongly recommended; scores should be good to excellent and appropriate for the breed
• Questionable findings should be referred to a canine sports medicine or veterinary rehabilitation specialist for advisement on the individual dog
• Working dogs should receive annual health exams throughout their working life to ensure that they are functionally healthy and able to continue working safely
• Screening radiographs/x-rays of hips/low back and elbows should be performed every 1–2 years after age 6, or any injury that occurs earlier, to monitor for early signs of repetitive injury or arthritis. Because shoulder tendons cannot be evaluated on x-ray, ultrasound evaluation of shoulder tendons is recommended.

Evaluated and cleared for work by a qualified specialized veterinarian^

• Not all general-practice veterinarians are familiar with the unique demands placed on working/ service dogs; the recommended x-rays (or ultrasound) require a veterinarian trained to accurately perform the tests and interpret the findings in relationship to a service dog’s job demands.
• Examples of qualified specialty veterinarians: Canine sports medicine and/or rehabilitation, often found under the orthopedic surgery specialty (search for a vet near you)

Dog is generally healthy, fit, and in excellent physical condition – throughout their working life

• Body Condition Score of 4–5 out of 9 on the Purina Body Condition System(iii) and have a normal lean muscle mass
• Dogs with higher body condition scores (overweight) have shorter life expectancy than those that are fit and lean, significantly increased injury risk, and shorter effective career longevity

Mobility/balance/guide assistance work is only done in an appropriate mobility assistance harness

• The harness shall be specifically designed for the work the dog will perform
• Shall be custom-fitted to the dog
• Distribute/equalize forces applied to the handle appropriately to reduce load on joints, muscles, etc.
• Appropriately distributes load forces, minimizes high pressure points and restriction of movement
• Avoids direct pressure on withers, shoulders and spine

Recommendations for Mobility Dog Prospects – Puppies and adolescents

• Avoid early spay/neuter to allow for normal growth; sex hormones affect the development of bones, joints, muscles and connective tissues (e.g., tendons, ligaments)
• Avoid high-impact, repetitive activity during muscular and skeletal growth and development to minimize strain on bones, joint, muscle and connective tissues
  – Examples of high-impact/repetitive activity: jumping out of a vehicle, playing fetch at high speed, jogging on pavement. In one study, young puppies exposed to stairs had a higher risk of developing dysplasia.
• Puppies and young dogs may wear a light, fabric service dog vest or general-purpose non-restrictive walking harness for foundation training
• Puppies should not exhibit body-sensitivity such as distraction, stress or avoidance when items touch their body (IE: wearing a vest or harness); some temperament tests evaluate this trait.
• Avoid mobility-specific, load-bearing activity (pulling, counterbalance, bracing) until the minimum age and fitness guidelines are met. This includes the use of a working/mobility harness and any type of harness handle until the dog is at least 18–24 months of age.

Best Practices for Light Mobility Assistance

Light mobility assistance may include guiding, light leading, and/or support through light contact with the harness handle (NO bracing or routine pulling).

• Minimum 18-24 months of age (depending on breed) AND has a fully developed muscular and skeletal system
• Weight of 50 pounds (22.6 kg) or more
• Height of 22” (56 cm) or taller at the withers
• An appropriate fitness/exercise routine is in place to maintain strength and fitness specific to job demands
• Distance between dog’s height and person’s hand is 8 inches or less for balance assistance
• Mobility/balance/guide assistance work is only done in an appropriate mobility assistance harness
• The harness shall be specifically designed for the work the dog will perform, and custom-fitted to the dog
• Harness shall distribute/equalize forces appropriately to reduce load on joints, muscles, etc.
• Have a non-rigid support handle; vertical handles should flex to absorb excess motion (a rigid guide handle with a flexible connection and longer length is acceptable)

Best Practices for Moderate to Heavy Mobility Assistance

Moderate assistance may include counterbalance and momentum pulling. Heavy assistance may include routine pulling and occasional bracing (downwards pressure).

• Dog is 2 years of age AND has a fully developed muscular and skeletal system
• Weight of 60 pounds (27.2 kg) or more for moderate mobility assistance
• Height of 24” (60 cm) or taller at the withers AND requires a rigid bracing handle of 6 inches or less
• Dog is at least 50% of partner’s weight for heavy assistance where bracing is performed (e.g., a person that weighs 150 pounds or less partnered with a dog that weighs 75 pounds or more)
• An appropriate fitness/exercise routine is in place to maintain strength and fitness specific to job
• Never expects the dog substitute for durable medical equipment such as a cane, crutch or walker frame
• Mobility/balance/guide/pulling/brace assistance work is only done in an appropriate mobility assistance harness that is:
  – Specifically designed for the work the dog will perform
  – Distributes/equalizes forces appropriately to reduce load on joints, muscles, etc.
  – Has been custom-fitted to the dog
• Bracing (downward pressure) if performed, is done conscientiously:
  – With a vertical, rigid (metal) harness handle that is 6 inches or less from the dog’s back to the handle grip. (Handle measurement is the difference between dog’s height and person’s hand/wrist)
  – Applies no more than a few pounds of pressure
  – Is performed only momentarily and occasionally
  – Must not push or pull the dog off-balance
  – Only when the dog is standing square – never while the dog is in motion

Additional Notes

We do not yet know what amount of work/load/pressure is safe for service dogs to perform. These recommendations are based on current veterinary knowledge and experience of canine biomechanics and the limited research on how harnesses impact a dog’s movement. We are providing these recommendations to minimize negative impact on the dog’s body and working life. Mobility Dog recommendations are subject to change as additional research and information becomes available.

References

Latest revisions made on March 23, 2024

Contributing editors and advisors include but are not limited to: founding members Jane Schappell and Katrina Boldry; Elle De Ford, MS, PhD, DVM, MCBC, cVMA, TCCC, CCRP; Cindy Otto, DVM, PhD, DACVECC, DACVSMR, CCRT; Sasha Foster, MS, CCRT; Colorado State University, J.L. Voss Veterinary Teaching Hospital Small Animal Orthopedic Medicine and Mobility

2021 AAHA Working, Assistance, and Therapy Dog Guidelines
Cynthia M. Otto, Tracy Darling, Lisa Murphy, Zenithson Ng
https://www.researchgate.net/publication/355721344_2021_AAHA_Working_Assistance_and_Therapy_Dog_Guidelines  

J Am Anim Hosp Assoc (2021) 57 (6): 253–277.

https://doi.org/10.5326/JAAHA-MS-7250

(i) OFA is a phenotypic evaluation of hip or elbow confirmation. OFA info: https://ofa.org/diseases/hip-dysplasia/,
https://ofa.org/diseases/elbow-dysplasia/ , https://ofa.org/diseases/hip-dysplasia/hip-grade-details/ (includes transitional vertebrae)

(ii) PennHIP “gives an estimate of the risk for painful osteoarthritis (OA) of canine hip dysplasia (CHD) later in life.”

(iii) www.purinainstitute.com

(^) Working Dog Practitioner – is a growing resource of veterinarians committed to working dogs

(iv) https://wsava.org/wp-content/uploads/2020/01/Muscle-Condition-Score-Chart-for-Dogs.pdf

(v) https://www.purinainstitute.com/science-of-nutrition/managing-healthy-weight; Kealy, R. D., Lawler, D. F., Ballam, J. M., Mantz, S. L., Biery, D. N., Greeley, E. H., Lust, G, Segre, M., Smith, G. K. & Stowe, H. D. (2002). Effects of diet restriction on life span and age-related changes in dogs. Journal of the American Veterinary Medical Association, 220(9), 1315–1320.

Penell, J. C., Morgan, D. M., Watson, P., Carmichael, S., & Adams, V. J. (2019). Body weight at 10 years of age and change in body composition between 8 and 10 years of age were related to survival in a longitudinal study of 39 Labrador retriever dogs. Acta Veterinaria Scandinavica, 61(1), 42. Salt, C., Morris, P. J., Wilson, D., Lund, E. M., & German, A. J. (2019). Association between life span and body condition in neutered client-owned dogs. Journal of Veterinary Internal Medicine, 33(1), 89–99.

Teng, K. T., McGreevy, P. D., Toribio, J. L., Raubenheimer, D., Kendall, K., & Dhand, N. K. (2018). Strong associations of nine-point body condition scoring with survival and lifespan in cats. Journal of Feline Medicine and Surgery, 20(12), 1110–1118.