Nonunion

Nonunion is the result of a fractured bone failing to heal after an extended period of time – in some cases over a period of 9 to 12 months. Several factors contribute to a nonunion. If the bone ends that are fractured have been stripped away from the blood vessels that provide them with nutrition, they will die. As a result, the bone ends cannot contribute to new healing, and a nonunion is more likely. Without a good blood supply and growth of new blood vessels, no new bone will form and the fracture cannot readily heal.

Nonunion of bone is the body’s inability to heal a fracture. Furthermore, nonunion is a complex orthopedic problem that is multifactorial, and clinicians need to entertain multiple modalities as therapeutic interventions. One must review radiographs to determine if there is evidence of fracture healing demonstrated by cortical bridging of the fracture lines. Also, clinical markers of healing must be evaluated, evidenced by a resolution of pain with weight-bearing with no movement at the fracture site. Patient comorbidities require evaluation to determine the risk factor’s for poor bone healing, and these factors must be optimized for fracture healing to occur.

Types of Nonunion:

Hypertrophic Nonunion

• Shown by radiographically abundant callus formation
• Importantly, there is no bridging bone, and the ends are not united
• This finding implies there is adequate blood supply and biology (with the formation of callus), but inadequate stability

Atrophic Nonunion

• Evidenced by radiographically absent callus, which indicates poor biology (from one or several of causes above) and a lack of blood supply (see above).
• Inadequate fixation

Oligotrophic

• Is a balance and combination of atrophic and hypertrophic in that there is incomplete callus formation
• Inadequate reduction

Septic Nonunion

• Reduces blood flow from organisms consuming the nutrition to healthy bone
• Decreases the new bone formation

The symptoms of nonunion fractures include:

• Swelling.
• Pain.
• Tenderness.
• Deformity.
• Difficulty bearing weight.

Treatment

Treatment for nonunion is always customized to the patient. In general, Orthopedic Specialist at Shreya Hospital will seek to determine why the fracture did not heal. A plan is then formulated to try to eliminate or limit any physiological reason why healing has not been successful.

Medical

In some cases, union can be achieved without surgery. Several non-invasive methods are available, such as electrical stimulation or specialized braces.

Surgical

Most nonunions require surgery. Surgical treatment is usually focused on three goals:

• Establishing a healthy vascular area of bone and soft tissue around the fracture site.
• This is accomplished by removal of any poorly dead bone or poorly vascularized tissue or scar from the fracture site. In some cases, the local tissues may be so badly damaged that plastic surgery in the way of rotational or microvascular free muscle flaps may be necessary to bring new healthy tissue to the fracture site.
• Establishing stability at the fracture site.
• This usually involves use of a rod, plate or screws. This may also involve use of an “external fixator” — external pins to hold the bones above and below the fracture.
• Stimulating a new fracture healing response using a bone graft.
• Bone grafts most often involve borrowing healthy cancellous or “spongy” bone from the pelvis, through a small incision at the level of the hip. This brings in many new bone forming cells and other supportive cells.