Review Question - QID 211586

Several studies have demonstrated significant improvement in mJOA scores at 1-year follow-up in patients with severe cervical spondylomyelopathy (CSM) (mJOA scores <12 preoperatively).

CSM is characteristic of step-wise neurologic deterioration with little success reported with nonoperative treatment. The modified Japanse Orthopedic Association (mJOA) score is a patient-reported outcome measure that is a validated method of determining the severity of pre-surgical myelopathy and post-op recovery. It assesses upper and lower extremity motor, sensory, and bladder function. Despite the presence of severe myelopathy, which is defined as mJOA <12, surgical decompression results in significantly improved mJOA scores from preoperative measures.

Fehlings et al. performed a large multicenter prospective study looking at outcomes of spinal cord decompression in patients with myelopathy. They reported there was significant improvement across all 3 mJOA cohorts (mild, moderate and severe) at twelve-months postop. The authors concluded that surgical treatment of cervical myelopathy directly improves patient functional outcomes.

Lim et al. performed a retrospective study on postoperative C5 palsy in 710 patients who underwent surgical treatment for cervical myelopathy. They found that C5 palsy occurred in 5.1% of cases with risk factors being greater than 3 surgical levels. Furthermore, they reported that prolonged recovery occurred in patients with a C5 motor grade less than or equal to 2, multilevel paresis, and sensory involvement with intractable pain. The authors concluded that patients with C5 palsy will tend to recover within 6 months from the onset of symptoms, but the findings of this study may prognosticate patients who may require a prolonged period of recovery.

Tetreault et al. performed a large multicenter international study of 614 patients undergoing surgical treatment for cervical myelopathy to determine preoperative factors to predict patient outcomes. The multivariate analysis revealed 6 factors that correlated with mJOA score ≥16 which included baseline mJOA score, impaired gait, age, comorbidity score, smoking status, and duration of symptoms. The authors concluded that their prognostic model is not designed to determine which patients would benefit the most from surgery but to guide presurgical expectations during the consent process.

Incorrect Answers:
Answer 1: Studies have demonstrated that patients undergoing surgery for CSM have significant improvement in outcome measures at long-term follow-up, even in severe cases.
Answer 2: In many studies, the cutoff for an excellent outcome following decompressive surgery for CSM is a mJOA score ≥16, which has corresponded to a high degree of independence for activities of daily living. However, this may not be frequently achievable with patients presenting with severe CSM (preoperative mJOA score <12).
Answer 3: In patients with severe myelopathy, complete resolution of neurologic symptoms is unlikely, albeit there may be an improvement following the intervention.
Answer 5: The goal of surgical treatment is to prevent the progressive step-wise neurologic deterioration of myelopathy, which is usually successful with surgery.