Clinical and Operative Factors Related to Successful Revision Arthrodesis in the Foot and Ankle.

BACKGROUND

Arthrodesis is a common operative procedure used to manage arthritis and deformity in the foot and ankle. Nonunion is a possible and undesirable outcome in any arthrodesis surgery. Rates of nonunion in the foot and ankle literature range from 0% to 47% depending on the patient population and joint involved. Multiple factors can contribute to developing a nonunion including location, fixation method, tobacco use, diabetes, infection, and others.

METHODS

The case logs of 3 foot and ankle surgeons were reviewed from January 2007 to September 2014 to identify nonunion arthrodesis revision cases. The patient factors reviewed included diabetes, inflammatory arthropathy, tobacco use, history of infection, nonunion elsewhere, neuropathy, Charcot arthropathy, posttraumatic arthritis, and prior attempt at revision arthrodesis at the same site. Operative records were reviewed to identify location of the nonunion, instrumention, use of allograft or autograft bone, use of iliac crest bone marrow aspirate (ICBMA) and use of orthobiologics such as bone morphogenetic protein (BMP) during the revision arthrodesis. Successful revision was defined as radiographic union on the final radiograph during follow-up. Eighty-two cases of revision arthrodesis were identified with an average follow-up of 16 months.

RESULTS

The overall nonunion rate was 23%. Neuropathy and prior attempts at revision were identified as significant risks (P <.05) for persistent nonunion. Odds ratio calculated based on previous attempts at revision arthrodesis found a 2.8-fold increase in the risk of failure for each attempt at revision.

CONCLUSION

Revision arthrodesis for nonunion in the foot and ankle was successful (77%) under a variety of patient and operative conditions. Neuropathy was a significant patient risk factor for persistent nonunions, and we believe it is important to identify even in the nondiabetic patient. As the number of attempts at revisions increases, there is a subsequent 3-fold increase in the risk of persistent nonunion.

LEVEL OF EVIDENCE: Level IV, case series.