1642 - When Spinal Manipulation Goes Wrong: A Case of Iatrogenic Lumbar Radiculopathy and the Role of Physiatry

A 65-year-old man with a remote history of poliomyelitis presented with acute right foot drop and lateral calf pain within one hour of a routine lumbar chiropractic adjustment targeting the right lower back. Neurologic exam revealed 0/5 strength in the right L5/S1 myotomes, along with sensory loss in the L5 dermatome. Electrodiagnostic studies confirmed a subacute, active right L5 radiculopathy, superimposed on chronic re-innervation consistent with prior poliomyelitis. MRI of the lumbar spine revealed moderate-to-severe right-sided foraminal stenoses at L4-5 and L5-S1. 

He was prescribed an oral corticosteroid taper, physical therapy, and right ankle-foot orthosis. Surgical evaluation did not recommend decompression due to limited likelihood of neurologic recovery.  


Discussions:

Although chiropractic adjustment/SMT is widely used for musculoskeletal complaints, serious complications are exceedingly rare, particularly in the lumbar spine. Most reported adverse events involve the cervical spine—including vertebral artery dissection—while lumbar complications like acute radiculopathy are rare.   

Although a direct causal link is difficult to establish in such cases involving the lumbar spine—given the high prevalence of pre-existing pathology in patients undergoing SMT—the close temporal relationship suggests that a high-velocity thrust likely precipitated mechanical nerve root compression. 

The incidence of major complications from lumbar SMT is estimated at < 0.003%, or just a few events per several hundred thousand procedures. Notably, MRI showed no large disc extrusion, suggesting that foraminal narrowing alone can predispose to acute nerve injury post-manipulation.  


Conclusions: This case highlights a rare but important complication of lumbar SMT: L5 radiculopathy with foot drop. While SMT is generally safe, clinicians and patients should be aware of the small but significant risk of neurologic injury in susceptible individuals. Physiatrists are essential in diagnosing nerve root injuries, coordinating electrodiagnostic studies, prescribing orthoses, and guiding functional recovery through patient-centered rehabilitation.