Nonunion | |
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Hypertrophic nonunion of the tibia | |
Specialty | Orthopedics |
Nonunion is permanent failure of healing following a broken bone unless intervention (such as surgery) is performed. A fracture with nonunion generally forms a structural resemblance to a fibrous joint, and is therefore often called a "false joint" or pseudoarthrosis (from Greek pseudo- , meaning false, and arthrosis, meaning joint). The diagnosis is generally made when there is no healing between two sets of medical imaging, such as X-ray or CT scan. This is generally after 6–8 months. [1]
Nonunion is a serious complication of a fracture and may occur when the fracture moves too much, has a poor blood supply or gets infected. Patients who smoke have a higher incidence of nonunion. The normal process of bone healing is interrupted or stalled.[ citation needed ]
Since the process of bone healing is quite variable, a nonunion may go on to heal without intervention in very few cases. In general, if a nonunion is still evident at 6 months post-injury it will remain unhealed without specific treatment, usually orthopedic surgery. A non-union which does go on to heal is called a delayed union. [2]
A history of a broken bone is usually apparent. The patient complains of persistent pain at the fracture site and may also notice abnormal movement or clicking at the level of the fracture. An X-ray plate of the fractured bone shows a persistent radiolucent line at the fracture. Callus formation may be evident but callus does not bridge across the fracture. If there is doubt about the interpretation of the x-ray, stress x-rays, tomograms or CT scan may be used for confirmation.[ citation needed ]
The reasons for non-union are:[ citation needed ]
There are typically three types of nonunion described.
In a hypertrophic nonunion, the fracture site contains adequate blood supply but the fracture ends fail to heal together. [6] X-rays show abundant callus formation. This type of nonunion is thought to occur when the body has adequate biology, such as stem cells and blood supply, but inadequate stability, meaning the bone ends are moving too much. Typically, the treatment consists of increasing stability of the fracture site with surgical implants. [7]
In an atrophic nonunion, x-rays show little to no callus formation. This is usually due to impaired bony healing, for example due to vascular causes (e.g. impaired blood supply to the bone fragments) or metabolic causes (e.g. diabetes or smoking). Failure of initial union, as when bone fragments are separated by soft tissue, may also lead to an atrophic non-union. Atrophic non-unions can be treated by stimulating blood flow and encouraging healing. This is often done surgically by removing the end layer of bone to provide raw ends for healing and the use of bone grafts. [8]
As the name implies, an oligotrophic nonunion demonstrates some attempt by the body to heal the fracture. These are thought to arise from adequate biology but displacement at the fracture site. [7]
A diagnosis of nonunion is made when the clinician feels there will be no further bone healing without intervention. The FDA defines it as a fracture at least 9 months old that has not shown any signs of radiographic healing within the last 3 months. [9] CT scans offer a closer look at the fracture and may also be used to evaluate how much of the fracture has healed. Blood tests can evaluate if the patient has adequate levels of nutrients such as calcium and vitamin D. Blood tests can also look for markers of infection such as ESR and CRP. [7]
Currently, there are different strategies to augment the bone-regeneration process, however, there is no standardised clinical treatment guideline yet. [9] Surgical treatment options include:[ citation needed ]
In simple cases, healing may be evident within 3 months. Gavriil Ilizarov revolutionized the treatment of recalcitrant nonunions demonstrating that the affected area of the bone could be removed, the fresh ends "docked" and the remaining bone lengthened using an external fixator device. [13] The time course of healing after such treatment is longer than normal bone healing. Usually, there are signs of union within 3 months, but the treatment may continue for many months beyond that.
Bone stimulation with either electromagnetic or ultrasound waves has been suggested to reduce the healing time for non-union fractures. [14] The proposed mechanism of action is by stimulating osteoblasts and other proteins that form bones using these modalities. The evidence supporting the use of ultrasound and shockwave therapy for improving unions is very weak [15] and it is likely that these approaches do not make a clinically significant difference for a delayed union or non-union. [16]
By definition, a nonunion will not heal if left alone. Therefore, the patient's symptoms will not be improved and the function of the limb will remain impaired. It will be painful to bear weight on it and it may be deformed or unstable. The prognosis of nonunion if treated depends on many factors including the age and general health of the patient, the time since the original injury, the number of previous surgeries, smoking history, the patient's ability to cooperate with the treatment. In the region of 80% of nonunions heal after the first operation. The success rate with subsequent surgeries is less.[ citation needed ]
Bone healing, or fracture healing, is a proliferative physiological process in which the body facilitates the repair of a bone fracture.
Rhinoplasty, commonly called nose job, medically called nasal reconstruction, is a plastic surgery procedure for altering and reconstructing the nose. There are two types of plastic surgery used – reconstructive surgery that restores the form and functions of the nose and cosmetic surgery that changes the appearance of the nose. Reconstructive surgery seeks to resolve nasal injuries caused by various traumas including blunt, and penetrating trauma and trauma caused by blast injury. Reconstructive surgery can also treat birth defects, breathing problems, and failed primary rhinoplasties. Rhinoplasty may remove a bump, narrow nostril width, change the angle between the nose and the mouth, or address injuries, birth defects, or other problems that affect breathing, such as a deviated nasal septum or a sinus condition. Surgery only on the septum is called a septoplasty.
Grafting refers to a surgical procedure to move tissue from one site to another on the body, or from another creature, without bringing its own blood supply with it. Instead, a new blood supply grows in after it is placed. A similar technique where tissue is transferred with the blood supply intact is called a flap. In some instances, a graft can be an artificially manufactured device. Examples of this are a tube to carry blood flow across a defect or from an artery to a vein for use in hemodialysis.
A bone fracture is a medical condition in which there is a partial or complete break in the continuity of any bone in the body. In more severe cases, the bone may be broken into several fragments, known as a comminuted fracture. A bone fracture may be the result of high force impact or stress, or a minimal trauma injury as a result of certain medical conditions that weaken the bones, such as osteoporosis, osteopenia, bone cancer, or osteogenesis imperfecta, where the fracture is then properly termed a pathologic fracture.
A clavicle fracture, also known as a broken collarbone, is a bone fracture of the clavicle. Symptoms typically include pain at the site of the break and a decreased ability to move the affected arm. Complications can include a collection of air in the pleural space surrounding the lung (pneumothorax), injury to the nerves or blood vessels in the area, and an unpleasant appearance.
External fixation is a surgical treatment wherein Kirschner pins and wires are inserted and affixed into bone and then exit the body to be attached to an external apparatus composed of rings and threaded rods — the Ilizarov apparatus, the Taylor Spatial Frame, and the Octopod External Fixator — which immobilises the damaged limb to facilitate healing. As an alternative to internal fixation, wherein bone-stabilising mechanical components are surgically emplaced in the body of the patient, external fixation is used to stabilize bone tissues and soft tissues at a distance from the site of the injury.
In medicine, the Ilizarov apparatus is a type of external fixation apparatus used in orthopedic surgery to lengthen or to reshape the damaged bones of an arm or a leg; used as a limb-sparing technique for treating complex fractures and open bone fractures; and used to treat an infected non-union of bones, which cannot be surgically resolved. The Ilizarov apparatus corrects angular deformity in a leg, corrects differences in the lengths of the legs of the patient, and resolves osteopathic non-unions; further developments of the Ilizarov apparatus progressed to the development of the Taylor Spatial Frame.
Achilles tendon rupture is when the Achilles tendon, at the back of the ankle, breaks. Symptoms include the sudden onset of sharp pain in the heel. A snapping sound may be heard as the tendon breaks and walking becomes difficult.
Bone grafting is a surgical procedure that replaces missing bone in order to repair bone fractures that are extremely complex, pose a significant health risk to the patient, or fail to heal properly. Some small or acute fractures can be cured without bone grafting, but the risk is greater for large fractures like compound fractures.
An ankle fracture is a break of one or more of the bones that make up the ankle joint. Symptoms may include pain, swelling, bruising, and an inability to walk on the injured leg. Complications may include an associated high ankle sprain, compartment syndrome, stiffness, malunion, and post-traumatic arthritis.
Autotransplantation is the transplantation of organs, tissues, or even particular proteins from one part of the body to another in the same person.
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A scaphoid fracture is a break of the scaphoid bone in the wrist. Symptoms generally includes pain at the base of the thumb which is worse with use of the hand. The anatomic snuffbox is generally tender and swelling may occur. Complications may include nonunion of the fracture, avascular necrosis of the proximal part of the bone, and arthritis.
A femoral fracture is a bone fracture that involves the femur. They are typically sustained in high-impact trauma, such as car crashes, due to the large amount of force needed to break the bone. Fractures of the diaphysis, or middle of the femur, are managed differently from those at the head, neck, and trochanter; those are conventionally called hip fractures. Thus, mentions of femoral fracture in medicine usually refer implicitly to femoral fractures at the shaft or distally.
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Regional acceleratory phenomenon (RAP) is a sudden acceleration of normal tissue processes in reaction to noxious stimuli. It has been exploited in treatments such as the healing of atrophic or oligotrophic nonunions and surgically facilitated orthodontic therapy.
Congenital pseudarthrosis of the tibia (CPT) is a rare paediatric disease presenting with a bowing deformity of the tibia at birth or within the first decade of life. It is most commonly associated with Neurofibromatosis type 1 (NF-1). For children with CPT, pathological fracture of the tibia eventually occurs, resulting in persistent nonunion of the fracture site. If left untreated, leg deformities, joint stiffness, leg-length discrepancy and pain will persist. Diagnosis is done clinically and through X-ray imaging, with numerous classifications based on the severity of bowing and presence of fracture or intraosseous lesion.
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