Complex Regional Pain Syndrome or Reflex Sympathetic Dystrophy (RSD)
Complex regional pain syndrome is a chronic neuropathic pain condition and typically a variety of anti-neuropathic medications are tried. These medications are used as adjuvants to help patients tolerate the progression of physical therapy. Thus far she has triad sub-therapeutic doses of Elavil and Lyrica. She reports side effects of cognitive impairment and sedation with both.
Neurontin and Lyrica are both calcium channel modulators and typical effective doses for Neurontin are between 900 and 1200 mg. t.i.d. and for Lyrica is 150 mg. b.i.d. These usually need to be titrated slowly so patients can acclimate to some of the transient cognitive impairment or sleepiness they can0cause. This could certainly be re-tried with patient.
Patients typically are unable to tolerate therapeutic doses of Elavil due to its anti-cholinergic side effects.
More favorable TCAs, including desipramine and Nortriptyline can be quite effective for neuropathic pain. Usual effective doses are between 100 and 150 mg. q a.m. for desipramine and q p.m. for Nortriptyline. These are titrated by 25 mg. each week and should not be used in conjunction with a mixed SNRI such as Cymbalta or SSRIs.
An alternative to the TCAs are the mixed SNRIs such as Cymbalta. This is typically titrated by 20 to 30 mg. every few days to a usual effective dose of between 90 and 120 mg. per day. Other medications such as sodium channel modulators include Mexiletine, Topamax, Trileptal and Lamictal.
Opiates tend to not be as effective with neuropathic pain conditions. Methadone is an exception given that it has a NMDA receptor antagonism that can actually be quite effective in controlling chronic neuropathic pain. Patients are usually maintained on lower doses between 5 and 10 mg. b.i.d. or t.i.d. Starting doses are always lower and titrated slowly to avoid over-sedation. Alendronate 40mg po q day for eight weeks as well as infusions of IV Pamidronate have been shown to be effective in treating CRPS.
Various other agents including nasal calcitonin, alpha adrenergic antagonists, anti-inflammatories, and immunomodulators have also been used to treat CRPS.
Topical agents such as lidocaine patches and ointments, Capsaicin creams as well as Flector-patches can be quite effective. There are also numerous compounded creams that in addition to lidocaine can include:
Ketamine, ketoprofen, and gabapentin.
Again, medications can help with controlling CRPS pain, but are primarily used as adjuvants for a physical therapy program.
Costs of medications are estimated: $6,000 a month would be reasonable over her lifetime on average.
Physical therapy is the mainstay of treatment. The pain may typically worsen as the CRPS develops, but discontinuing therapy would only make the sequelae of CRPS worse. Mobilization of her leg is extremely important to avoid decreased joint and tendon range of motion, disuse atrophy, and loss of limb function. Patients currently runs the risk of developing a left hip flexion contracture and further disturbances in her gait and mobility.
Desensitization techniques are needed to address her left thigh tactile allodynia and help restore more normal sensory processing. Working with a physical therapist who specializes in chronic and neuropathic pain syndromes is also important. Initial attempts at therapy undoubtedly lead to pain flares and a therapist skilled in teaching pacing techniques and greater progression of therapeutic interventions is of paramount importance to achieve a successful outcome. With patients, this would best be accomplished in the setting of a functional restoration program where she would learn to manage her pain and significantly improve her activity tolerance and functional use of her leg.
Functional Restoration Programs (FRP)
There is no specific cure for complex regional pain syndrome but most people would agree that a multidisciplinary approach is required to successfully treat this difficult condition. Functional restoration programs have the opportunity to implement the above outlined therapies in an interdisciplinary and coordinated fashion. FRP physicians, physical therapists and pain psychologists are skilled in the management of chronic pain and provide patients the best opportunity for maximum recovery and improve their quality of life.
The cost of an FRP program would be $40,000 excluding hotel costs and meals over eight weeks including s six month aftercare program.
Interventions with regional anesthesia are often used with complex regional pain syndrome. She has had a few lumbar sympathetic blocks which have provided mild transient relief of her symptoms. This would indicate a sympathetic component to her pain, but it is unlikely that further local anesthetic/steroid blocks would provide any more than the short-term relief she has experienced. Dr. Ian Carroll at Stanford has had good success with Botox lumbar sympathetic blocks in providing sustained relief in patients with lower extremity CRPS. Given the proximity of her thigh pain, Bier blocks would not be indicated.
Other interventions include a left lateral femoral cutaneous nerve block or left L2-4 selective nerve root blocks with local anesthetic and steroid. If these provide good but temporary relief, pulsed radiofrequency ablation can be used to provide many months of relief.
Costs of nerve blocks are also difficult to estimate at this point in her medical care but it is recommended that $7,500 on average a year be set aside over her lifetime for this.
Cost of spinal cord stimulation can be quite effective for pain due to complex regional pain syndrome.
The initial cost of a trial and then implantation would be $60,000 and $10,000 should be allocated on average yearly to deal with side-effects, revisions and replacement units.
Trials of intrathecal medications including opiates, local anesthetics, baclofen, clonidine and Prialt are also treatment options. The cost of a trial, implantation and pump maintenance is $60,000 initially and $12,500 should be allocated on average yearly to deal with side-effects, revisions and replacement units.
CRPS can certainly lead to progression of anxiety and depression. There is a high rate of secondary psychiatric problems in patients with CRPS as they find significant difficulty coping with their ongoing pain and loss of function. Working with a pain psychologist would be important for patients to help overcome any fear of reinjury and manage changes in mood as it relates to pain. Of equal importance, a pain psychologist would help her develop cognitive behavioral strategies to better manage her chronic neuropathic pain using highly effective non-pharmacologic techniques.
The cost of psychological care would be 12 visits/year over her lifetime at $250/visit.
The cost of physician visits would include monthly visits over her lifetime at $150/visit.
The costs of blood tests and radiological studies would average $5,000/year.
Please understand that the above recommended costs are averages but they are my best medical opinion in regards to what would be probable based on my current information base.