CT-guided bone biopsy: when it is needed, how it is done and how safe it is

What a bone biopsy is

A bone biopsy removes a small sample from a bone lesion so that a pathologist and microbiologist can examine it. For a lesion that has broken through the bone surface, the sample may come from the soft tissue next to it. For a lesion inside the bone, a special bone needle, sometimes powered by a small drill, is used to pass through the hard outer layer.

Why it is done

A biopsy is considered when the scan alone cannot tell what a bone lesion is.

• A new or unexplained lesion in a vertebra, pelvis, rib or long bone.
• Suspected spread of cancer to bone, when the type or the receptor status is not known.
• Suspected bone or disc infection (osteomyelitis or spondylodiscitis), to find the organism.
• A suspected primary bone tumour, after planning with the bone tumour team.
• A fracture with no clear cause, such as a possible pathological fracture.

How it is done

Most bone biopsies take 30 to 60 minutes in total.

• A planning CT scan is done, and the safest route is chosen and marked on the skin.
• You lie in the position that gives the best access, often on your front or side.
• The skin and the tissue down to the bone surface are numbed. Sedation is added if needed.
• A coaxial needle is advanced under CT. Through it, a bone biopsy needle takes one or more cores. For infection, samples are also sent for culture.
• A dressing is placed. You rest for a short while and, if all is well, go home the same day.

What affects the result

The likelihood of a useful sample depends on the lesion: lesions that destroy bone and have a soft-tissue component are easier to sample than dense, hard (sclerotic) ones. Taking antibiotics shortly before a biopsy for infection can lower the chance of growing the organism, so the timing is planned with your doctors. In diabetic foot osteomyelitis, a pooled analysis found 84% of percutaneous biopsies were culture-positive, though the evidence on safety and on how results change treatment is limited ^[1]. If the first sample is not conclusive, a repeat or a different approach may be advised.

Suspected bone sarcoma: plan first

If a primary bone tumour such as an osteosarcoma or Ewing sarcoma is possible, the biopsy path matters. The needle track can carry tumour cells, and the surgeon may need to remove the whole track along with the tumour at the operation. For this reason the biopsy should be planned with, or done by, the centre that will treat the tumour, rather than in a hurry elsewhere. Your doctor will say if this applies to you.

Risks and aftercare

Bleeding, infection and soreness at the site are the main effects. Biopsies near the spine carry a small risk of nerve irritation, and biopsies of the ribs or upper spine can cause a pneumothorax. Deep biopsies are in the higher bleeding risk group, so blood tests and blood thinners are checked beforehand ^[2]. Afterwards, rest, avoid heavy lifting or strenuous activity for the period you are advised, and call for fever, bleeding, worsening pain, or new weakness or numbness.

Cost and insurance

Health insurance can cover these procedures, subject to your policy terms. The exact cost is calculated after consultation, a complete evaluation of the problem, and a decision on the procedure that suits you. Cashless treatment can be arranged with major Indian health insurers and TPAs, and credit treatment is available for CGHS and Singareni beneficiaries. Eligibility is confirmed after a policy check.