Delayed fracture healing in veterinary medicine: Causes, modern diagnostic methods and shock wave therapy (ESWT)
A guest article by Kirsten Häusler, small animal rehabilitation specialist
Fractures in dogs, cats and other small animals are among the most common orthopaedic problems encountered in veterinary practice. With proper treatment, a fracture usually heals within a few weeks. However, this process does not always run smoothly. Delayed healing can result in prolonged pain, reduced mobility and, in the worst-case scenario, even the amputation of a limb for the animal. To prevent this, a thorough understanding of the causes and the use of modern treatment approaches are required. Kirsten Häusler’s findings demonstrate how innovative methods such as shock wave therapy can play a crucial role in the healing process – in this case, specifically in dogs.
Why bones sometimes don’t heal
If healing takes longer than expected, this is referred to as »delayed fracture healing«. If a bone fails to heal completely, pseudarthrosis – a »false joint« – may develop. These problems have a variety of causes:
- Mechanical factors such as unstable fixations or incorrect loading
- Circulatory problems resulting from trauma or implants
- Infections and dead tissue
- Implant complications such as screw or plate fracture
- Bone loss due to inactivity (disuse osteopenia)
- Stress shielding, when implants bear too much of the load
- Malnutrition, particularly vitamin D or calcium deficiencies
These factors often interact and make recovery considerably more difficult.
Accurate diagnosis of the condition to ensure the right treatment strategy
Successful treatment begins with a thorough analysis. In addition to the patient’s medical history – including diet, physical activity and previous medical conditions – imaging techniques such as X-rays, CT scans or MRI scans provide information about the structural condition. Objective gait analysis provides valuable data for functional assessment. It shows how much weight is being placed on the affected limb, identifies compensatory patterns and enables comprehensive monitoring of treatment – all without the need for anaesthesia.
Focused shock wave therapy: Mechanism of action
In human medicine, focused shock wave therapy (F-SW) is already an established part of the treatment of slow-healing fractures. It has also achieved impressive results in the veterinary field. The mechanism of action involved is based on what is known as mechanotransduction. Put simply, this means that cells detect mechanical stimuli – in this case, the brief pressure pulses of shock waves – and convert them into biological responses. This mechanical stimulation triggers various signalling cascades within the tissue. Among other effects, it leads to the release of signaling molecules such as nitric oxide (NO) and to increased production of various growth factors and bone morphogenetic proteins (BMPs), which play a key role in bone metabolism.
The main effects of shock waves:
- Release of growth factors (VEGF, TGF-β, IGF-1)
- Promotion of new blood vessels and improved blood circulation
- Stimulation of bone-forming cells (osteoblasts)
- Activation of the body’s own repair mechanisms for cell regeneration
These stimuli accelerate callus formation and stimulate bone remodelling – a principle that follows the natural law of bone adaptation.
Case study: Preservation of the toe through the use of combination therapy
The case of a five-year-old female German Shepherd demonstrates just how effective modern approaches can be. Following a toe fracture, the injury did not heal despite conservative treatment, making amputation seem inevitable. By using a combination of focused shock wave therapy and low-level laser therapy, the healing process was reactivated. The associated wound on the calcaneus also healed, mobility improved significantly, and amputation was avoided. The gait analysis provided objective evidence of functional progress.
Summary: A revolution in veterinary medicine – progress that can change lives
Delayed fracture healing in small animals is not an inevitable fate, but a treatable challenge. Through precise diagnosis, personalised treatment plans and modern, non-invasive shock wave therapy, healing processes can be specifically promoted, complications reduced and, in many cases, amputations avoided. As a result, pain relief, quicker recovery, and better quality of life benefit both the animal and its owner.
