Abstract
Introduction
The regionalisation of major trauma in the UK has significantly improved outcomes for patients with severe, lower limb injuries. Chronic pain after complex lower limb injuries is well documented, but seems to remain a problem despite better clinical and radiological outcomes. We hypothesised that pain was mediated through the saphenous nerve, especially as most tibial injuries affected the soft tissues medially. As a proof of concept, we undertook adductor canal blocks to understand pain aetiology.
Materials & Methods
Patients with chronic pain following complex lower limb trauma or congenital deformity correction have been selected and underwent an adductor canal block by one of our trauma anaesthetist that specialises in this procedure. Their outcomes were recorded in their clinical records and patients were contacted by phone to document their experiences.
Results
14 patients with chronic, treatment refractory lower limb pain who were being managed in our orthoplastics clinic following complex, lower limb trauma were identified. Six of those patients had required plastic coverage. Of these 14 patients, all stated their pain completely resolved after the procedure and then returned between 24 hours and 4 weeks after the procedure. Two patients underwent a saphenous nerve diversion after conduction of the blocks, reporting subsequent resolution of their complaints.
Conclusions
As a proof of concept, we report that the saphenous nerve underlies chronic pain in patients with complex lower limb injuries. An adductor canal block is an effective diagnostic tool for these patients. Saphenous diversion may offer a permanent solution in patients who respond well to saphenous nerve block. A prospective study is planned to objectively measure pain and quality of life scores after treatment of complex injuries and pre and post adductor canal block.
