Revision Cervical Fusion

There are several reasons a previous neck fusion might need further surgery. The bone may not have fused solidly, leaving a persistent non-union (pseudarthrosis) that can cause ongoing pain or hardware problems. A level next to the fusion may degenerate and compress the nerves or cord over time, a well-recognised phenomenon known as adjacent segment disease. Less commonly, there may be issues with the position or integrity of the original implants, or continuing or recurrent compression. Careful assessment — clinical and radiological, sometimes with CT to judge fusion — establishes exactly what the problem is before any revision.

Revision cervical fusion can be approached from the front (anterior), the back (posterior), or with a combined operation, depending on the problem. A failed anterior fusion, for example, may be revised by redoing or reinforcing the anterior construct, or by adding posterior fixation to provide a more powerful environment for the bone to unite. Adjacent segment disease is treated by decompressing and, where needed, extending the fusion to include the worn segment. The approach is chosen to address the specific failure while giving the best chance of a solid, stable result.

One well-established principle in revision cervical fusion is that adding posterior fixation can substantially improve the chances of a stubborn non-union finally healing. Where an anterior fusion has failed to unite, supplementing it from the back — for example with posterior cages or screws — creates a stiffer, better-supported environment for bone to bridge. Tissue-sparing posterior techniques can achieve this with less disruption than traditional open surgery. The strategy is selected to match the individual pattern of failure.

The evidence guides revision cervical surgery. Meta-analyses of treatment for symptomatic cervical pseudarthrosis show that revision — and in particular the addition of posterior fixation — achieves high rates of eventual union and symptom improvement. Studies of adjacent segment disease after anterior cervical fusion describe its incidence and the outcomes of repeat anterior versus posterior fusion, informing approach selection. Reports of tissue-sparing posterior cervical fusion to revise a pseudarthrosis show good safety and results. This literature underpins a tailored, evidence-based approach to each revision.

Revision cervical fusion is planned meticulously around the specific reason the previous surgery needs revisiting, the imaging, and the individual's overall health. The realistic benefits, the risks — which are generally higher than for first-time surgery — and the alternatives are discussed in detail. The goal is a stable, solidly fused and decompressed neck, with a recovery and rehabilitation plan tailored to the operation performed.

• —Chen Z, et al. Clinical and fusion results after treatment of symptomatic cervical pseudarthrosis: a meta-analysis. 2015. (PMID 25844290)
• —Wewel JT, et al. Anterior cervical pseudarthrosis treated with bilateral posterior cervical cages. 2017. (PMID 28637309)
• —Nemani VM, et al. Adjacent segment disease after ACDF: anterior versus posterior repeat cervical fusion. Spine 2014. (PMID 24843815)
• —Smith W, et al. Tissue-sparing posterior cervical fusion to revise a pseudarthrosis: multicentre review of 150 cases. 2024. (PMID 38957762)
• —Lin GX, et al. Risk factors and adverse outcomes associated with ACDF: a systematic review. 2024. (PMID 38957769)