Definition & Overview
The excision of bone is a medical procedure that can be performed to remove bone abscess or infection. It is a more radical treatment option for persistent osteomyelitis or severe abscess when other treatment methods, such as medications, have failed. Prior to excision, the infection is drained and necrotic tissue is debrided. The procedure is expected to remove the infection or abscess completely, resulting in remission. This means the patient becomes completely cured after the procedure.
Who Should Undergo and Expected Results
The procedure can be recommended for patients who suffer from osteomyelitis. This is a bone infection caused by different types of bacteria, including staphylococcus aureus bacteria, which often affect the femur, distal tibia, proximal tibia, and the fibula. The infection develops when the bacteria settle on a small part of the bone and multiply. Bacteria can reach the bone through the bloodstream or a broken bone that has cut through the skin. The infection may also spread from nearby structures. An ongoing bacterial infection can cause the bone to swell and break if left untreated.
The procedure can also be recommended for patients with bone abscess or a pus-filled pocket that forms within the bones. It usually forms when an active infection is left untreated. Prior to bone excision, the abscess has to be removed. One type of bone abscess, also known as the Brodie's abscess, is considered as a subacute form of osteomyelitis.
A bone infection or abscess can cause the following symptoms:
- Pain and tenderness over a localised area
- General feeling of being unwell
- High fever
- Unexplained weight loss
Patients who are at risk of developing osteomyelitis include those who:
- Have recently suffered a fracture or broken bone
- Have a bone prosthesis in place
- Have had any kind of bone surgery
- Have diabetes or diabetic foot ulcer
- Have a compromised immune system
- Are alcohol dependent
- Have previously experienced osteomyelitis
- Have a blood disorder
- Regularly take steroids
- Require kidney dialysis
Surgical treatment is not the primary option for the management of osteomyelitis or bone abscess. Patients commonly undergo medical therapy first. Unfortunately, doctors are prompted to prescribe surgery if:
- Medical therapy does not work
- The infection is chronic
- The condition involves soft tissue abscess
- There is subperiosteal collection
- There is a concomitant joint infection
- There is neural compression
- There is spinal instability
In general, the surgical excision of bone for osteomyelitis is indicated in stages 3 and 4 of osteomyelitis. This is based on the Cierny-Mader classification system for osteomyelitis.
When performed properly on the right patients, this procedure is likely to completely cure osteomyelitis or bone abscess and prevent recurrence.
How is the Procedure Performed?
Prior to bone excision, the affected area is first prepared by:
- Debriding necrotic tissues
- Removing foreign materials
- Draining the infection
- Making sure surface skin wounds are fully closed
- Making sure any existing fracture in the treatment area has healed
After these preparations, the patient is placed under anaesthesia. The doctor then begins the procedure, which is performed using CT scanning as a visual guide. The procedure is performed through the following steps:
- The surgeon makes the necessary incisions to gain access to the affected part of the bone.
- Focusing on the infection site or the abscess, the surgeon then excises the tumour or the abscess.
- The incision is closed with sutures.
- The surgeon then ensures that there is no dead space (or the soft tissue/bone defect that gets left behind after debridement). The surgeon also ensures that there is adequate soft tissue coverage and that the blood supply to the surgical area is restored.
The management of dead space plays a key role in the long-term success of the procedure. The dead space has to be filled with vascularised tissue, which is usually taken from the ilium or fibula. Managing the dead space properly can help reduce the risk of recurrences and ensure the stability of the bone.
Possible Risks and Complications
Patients who undergo the procedure are at risk of the following:
- Damage to vital nerves and blood vessels
- Pin-tract infections
- Flexion contractures
- Bone fragment rotation with malunion
- Shortening of the affected bone
- Blood poisoning
- Soft tissue atrophy
Recurrence is more likely when there is poor vascularisation in the treated area. This can occur as early as weeks after the procedure or as late as several years after.
Gupta RC. “Treatment of chronic osteomyelitis by radical excision of bone and secondary skin-grafting.” J Bone Joint Surg Am. 1973 Mar; 55(2): 371-374. http://jbjs.org/content/55/2/371
Carek PJ, Dickerson LM, Sack JL. “Diagnosis and management of osteomyelitis.” Am Fam Physician. 2001 Jun 15; 63(12): 2413-2421. http://www.aafp.org/afp/2001/0615/p2413.html