Arachnoiditis remains a difficult condition to treat, and long-term outcomes are unpredictable. Most treatments for arachnoiditis focus on pain relief and the improvement of symptoms that impair daily function. A regimen of pain management, physiotherapy, exercise, and psychotherapy is often recommended. Surgical intervention is controversial since the outcomes are generally poor and provide only short-term relief. Clinical trials of steroid injections and electrical stimulation are needed to determine the efficacy of these treatments.
This answer is based on source information from National Institute of Neurological Disorders.