SHM Converge Scientific Abstract ePoster Gallery-Leg Stiffness After Open Reduction Internal Fixation of Right Hip: Normal Recovery or Rare Autoimmunologic Disorder?

Pdf Summary

This case describes a 64-year-old woman with diabetes, anxiety, chronic gait difficulty, spasticity, and falls who presented with an acute right hip fracture after being lifted from bed. After open reduction and internal fixation, she developed worsening bilateral leg rigidity, upper extremity stiffness, severe pain, and inability to tolerate passive movement. Initial evaluation showed markedly elevated CK, mild kidney injury, and MRI of the brain and spine that was unrevealing, raising concern for postoperative rhabdomyolysis or a neurologic disorder.<br /><br />Further workup revealed myopathy with distal axonal polyneuropathy, and cerebrospinal fluid testing showed elevated GAD65 antibodies, supporting stiff person spectrum disorder (SPSD). Her presentation fit the broader SPSD picture of asymmetric progressive stiffness, painful spasms, gait impairment, and association with anxiety and type 2 diabetes. The article emphasizes that SPSD is rare but likely underdiagnosed because it can mimic Parkinson’s disease, atypical parkinsonism, multiple sclerosis, and functional neurologic disorders.<br /><br />The proposed mechanism is autoimmune: anti-GAD antibodies reduce GABA synthesis, leading to neuronal hyperexcitability. Diagnosis is supported by high GAD65 titers and continuous motor unit activity on EMG, though antibodies are not always present.<br /><br />Treatment recommendations include first-line high-dose benzodiazepines and baclofen, with other GABAergic agents such as gabapentin as adjuncts. For severe or refractory symptoms, IVIG may be used. In this patient, treatment with benzodiazepines, baclofen, and gabapentin led to gradual improvement and discharge.<br /><br />Overall, the case highlights the importance of considering SPSD in patients with unexplained stiffness, spasms, pain, and negative MRI findings, especially when symptoms worsen after trauma or surgery.

Asset Subtitle

Claire E. Wild

Meta Tag

Author List Claire E. Wild, Ethan Molitch-Hou, Maria Young

Category Clinical Vignettes

Concept Stiff Person Spectrum Disorder

Concept Rigidity

Concept Muscle Spasm

Concept GAD65 Antibody

Concept Continuous Motor Unit Activity

Distinguished Non-Finalist

Presenter Organization The University of Chicago Pritzker School of Medicine

Presenting Author Claire E. Wild

Track Adult

Keywords

stiff person spectrum disorder

GAD65 antibodies

autoimmune myopathy

rhabdomyolysis

spasticity

painful spasms

gait impairment

benzodiazepines

baclofen

intravenous immunoglobulin

Stiff Person Spectrum Disorder

Rigidity

Muscle Spasm

GAD65 Antibody

Continuous Motor Unit Activity