Non Union

CY/RR/HC/YD/RG

Definition

• Nonunion failure of fracture bone to unite

Diagnosed can determined clinically / radiographically that healing has ceased and union is highly improbable

Etiology

(1) distraction and separation of the fragments, sometimes the result of interposition of soft tissues between the fragments;

(2) excessive movement at the fracture line(3) A severe injury that renders the local tissues

nonviable or nearly so(4) a poor local blood supply(5) infection

Classification

(1) Hypertrophic(2) Atrophic(3) Oligotrophic

Hypertrophic

• Hypervascular • Possess bioligic capacity to heal but lack mechanical

stability• Callus formation present on x-ray• Elephant foot - abundant callus• Horse hoof - less abundant callus

atrophic

• avascular and lack the bioogic capacity to heal• similar to oligotrophic on x-ray

Oligotrophic

• No callus on x-ray• Vascularity is present on bone scan

A B C D

Hypertrophic non-unions often have florid streams of callus around the fracture gap – the result of insufficient stability. They are sometimes given colourful names, such as: (a) elephant’s foot. Atrophic non-unionsusually arise from an impaired repair process; they are classified according to the x-ray appearance as (b) necrotic, (c) gap and (d) atrophic.

Treatment

• Nonoperative• Operative

Nonoperative

• Ultrasound• Electric stimulator• Bone marrow injection

Ultrasound• Ultrasound fracture stimulation devices

have shown ability to increase callus response in fresh fractures (shortens time for visible callus on x-ray)

• Use in nonunions remains theoretical

Electric Stimulation

• Piezoelectric nature of bone - stress generated electric potentials exist in bone and are related to callus formation

• Electromagnetic fields influence vascularization of fibrocartilage, cell proliferation & matrix production

Bone Marrow Injection

• Percutaneous bone marrow injected to level of fracture

Surgical Treatment

• Fibular osteotomy• Bone graft• Plate osteosynthesis• Intramedullary nailing• External fixation

Fibular Osteotomy

• Often used as adjunctive procedure to assist with deformity correction and surgical stabilization of tibia

Bone Grafting

• Osteoinductive - contain proteins or chemotactic factors that attract vascular ingrowth and healing

• Osteoconductive - contains a scaffolding for which new bone growth can occur

Bone Grafting

• Used to stimulate biologic response of healing in nonunions (usually atrophic nonunions)

• Also used to fill defects in fracture zone – i.e. up to 6 cm intercalary defects of long bones)

Bosse, MJ e.t.al. JBJS 1989

Plate Osteosynthesis• Restores function & stabilizes fracture fragments

directly• Compresses fragments in some circumstances to

augment healing• Often used with adjunctive bone graft

Intramedullary Nailing

• Mechanically stabilizes long bone nonunions as a load sharing implant

• Corrects malalignment• Reaming is initially detrimental to intramedullary

blood supply, but it does recover and is believed to stimulate biologic healing at fracture

External Fixation• Correct malalignment• Used primarily in management of infected nonunions

THANK YOU

• 45-year old lady has nonunion of closed fracture lower third shaft of tibia of nine months duration. The most likely cause of this nonunion is

A.comminution of the fractureB.distraction of the fragmentsC. interposition of soft tissueD.absence of muscle origin from itE. intact fibula

• How to treat atrophic non union ?(disuse atropic,disuse osteoporosis and leg length discrepancy 10 cm)

• Explain therapy non union fr. with infection?