20. Strategies for addressing failed cervical total disc replacement: a series of 42 patients

BACKGROUND CONTEXT

As with any spine surgery, there are failures with cervical total disc replacement (TDR). These may generally be classified as surgeon or technical error (including patient selection), biomechanical failure, biological (osteolysis, allergy, etc.) or other reasons. Surgeons performing TDR should be aware of the types of failure leading to the need for subsequent surgery and have a strategy to address these situations.

PURPOSE

This study's purpose was to describe modes of failure of cervical TDR and related treatment strategies.

STUDY DESIGN/SETTING

The study was based on detailed record review.

PATIENT SAMPLE

This study included a consecutive series of 42 patients (57 disc levels) undergoing cervical TDR removal or revision surgery.

OUTCOME MEASURES

Outcome was based on the TDR removal or revision surgery, reason for removal/revision, duration from implantation to removal/revision, and estimated blood loss during the procedure.

METHODS

A surgery log was reviewed to identify patients undergoing cervical TDR removal/revision surgery, including those whose index TDR was implanted at remote facilities. Chart review was conducted to collect general descriptive data, reasons for TDR removal/revision, duration from index implantation to re-operation, and the subsequent procedure performed.

RESULTS

Among the 42 patients, 31 underwent TDR removal and ACDF, TDR removal and replacement with another TDR was performed in 10 patients, and in one patient the TDR was revised by repositioning it. The mean blood loss was 37.2 ml (range: 5-150 ml). The mean duration from the index surgery to removal/revision was 37.6 months (range: 0 to 216 months). In all cases, removal/revision surgery was completed without complication. The most common reason for removal was severe osteolysis, often involving C. acnes infection, and was primarily associated with one implant type. TDR removal and fusion were also performed in cases of subsidence, device migration, treatment of symptoms arising from posterior anatomy (facet joints, posterior osteophytes, stenosis, etc.) or approach-related complications and pain. TDR replacement was feasible in cases with hypermobility, metal allergy (after a nonmetallic device became available), and for oversized implant use (provided a smaller implant design was available). In one case of symptoms related to TDR malpositioning, the device was successfully revised into appropriate position.

CONCLUSIONS

For cases of cervical TDR failure, replacing a TDR with another such implant is feasible in some patients. Reasons for revision or removal after C TDR surgery include biomechanical failure, implant migration, surgeon or technical error, or biological reasons (osteolysis, metal allergy, etc.). The type of failure can help the surgeon create a strategy to address these complications.

FDA Device/Drug Status

This abstract does not discuss or include any applicable devices or drugs.