Non union of clavicle fracture is a complication especially in type II distal clavicle fracture. Most of the nonunions may are asymptomatic but when symptomatic, it and can cause significant disability. The nonunion rate has been reported to be between 0.1% and 15%.
Nonunion usually describes a fracture that has not adequately healed between 6 and 9 months after injury. Symptoms include pain, paresthesia, and extremity weakness from neurovascular entrapment, shoulder weakness from disturbed shoulder mechanics, crepitation at the fracture site and unacceptable cosmetic appearance.
Factors Associated with Development of Non union of Clavicle Fracture
Type II fracture
Type II fracture of clavicle carry a higher risk of non unions.
Degree of Displacement
Shortening or displacement of 2 cm or more is associated with more chances of non union of clavicle fracture. Displacement to the point of potential soft-tissue interposition may be an important variable.
Severity of Trauma
The more severe the initial trauma the higher the rate of subsequent nonunion.
Refracture has clearly been demonstrated as an independent risk factor for nonunion.
Age of Patient
Patient with older age have higher risk of developing a non union of clavicle fracture as compared to patients in younger age.
Treatment of Nonunion
Symptomatic non union of clavicle fracture should be treated. Pain at the nonunion site is the most frequent symptom and thus the most common reason for operative intervention. Static or progressive neurovascular compromise is another indication for surgery.
There are various procedures described for non union of clavicle fracture and these can be divided into two main categories
Salvage procedures attempt to alleviate symptoms or deformities without achieving bone union. Reconstructive procedures, however, are designed to achieve bone union.
- Removing a bony prominence
- Partial or total clavicle removal so that l grating or neurovascular compromise is relieved.
Thes include fixation methods for the treatment of non union of clavicle fracture.
Intramedullary pin fixation and Autogenous Bone Grafting
Advantages of intramedullary pinning over other forms of fixation, particularly plate and screw osteosynthesis, include cosmetically acceptable incision, less dissection of the soft tissues, easy removal of the hardware, lesser risk of osteoporosis as it is load sharing device.
However, there is disadvantage of this technique of lack of rotational control with the pin.
Rush pins, Knowles pin, threaded Steinmann pins have been used for treatment of non union of fracture clavicle with success.
Plate and Screw Osteosynthesis and Autogenous Bone Grafting
Plating and bone grafting for midshaft nonunions has become a well-established treatment option. This method is favored over intramedullary fixation for treatment of non union of clavicle fracture for several reasons
- Iimproved rotational stability
- Ability to incorporate an intercalary graft
- No fear of implant migration
Technique consists of debridement and trimming of the bone ends, placement of a cortical bone transplant posteriorly and metal plate anteriorly, and fixation of the plate to the clavicle and cortical bone transplant with screws.
Advantages of plate and screw osteosynthesis over other methods of fixation include excellent control of rotation and the ability to restore the normal length of the clavicle.
Disadvantages to plate fixation include the need for wider exposure and increased periosteal stripping, which can disturb the blood supply to the healing fragments. Also, a larger exposure is required for hardware removal.
This method requires patient in general anesthesia with endotracheal intubation and then is placed in the 50° beach chair position, with the head secured to a Mayfield headrest. The injured upper extremity and the ipsilateral or contralateral iliac crest region are prepared and draped.
With a lazy S type of incision over the involved clavicle,fracture is exposed and fibrous nonunion is debrided and fracture is reduced after debriding fibrous nonunion tissue and removing atrophic, sclerotic bone ends.
In the resultant defect, tricorticocancellous bone graft, obtained from iliac crest is placed between the proximal and distal clavicle fragments. The plate is secured to the clavicle with one or two cortical screws placed in the interpositional fragment and three or four cortical screws placed in each of the medial and lateral fragments.
For 6 weeks after surgery, the patient wears a sling and performs passive range-of-motion exercises with passive forward elevation limited to 90° till the bone unites.
Free Fibular Vascularized Transfer
For recalcitrant midshaft clavicular nonunions, the use of a free-fibular vascularized graft is a surgical option.This should be used when other fixation techniques fail.
Electrical Stimulation and Low-Intensity Pulse Ultrasound
These techniques should be considered only when surgical intervention is impossible in non union of clavicle fracture.
Get more stuff on Musculoskeltal Health
Subscribe to our Newsletter and get latest publications on Musculoskeletal Health your email inbox.
Thank you for subscribing.