Case Study: Peripheral Nerve Blocks in Management of Complex Regional Pain Syndrome
Shashank Saxena, M.D., Nashaat N. Rizk, M.D., Doris K. Cope, M.D.
Department of Anesthesiology
University of Pittsburgh School of Medicine
CASE REPORT 1 CASE REPORT 2 CASE REPORT 2
A 16-year-old healthy female was referred to the pain clinic for A 36-year-old female was referred to the pain clinic for persistent right A 51-year-old male presented to the pain clinic with complaints of left
persistent right knee pain and for evaluation of complex regional pain thigh pain. She sustained injury on her right thigh eleven months prior foot pain since 1999. He sustained injury in January 1999 when he
syndrome. She had previously been prescribed zolpidem 2.5 mg qhs when a car fell off a jack onto her right thigh. Her injury was fell down on ice. Pain, described as mostly sharp, was confined to the
and gabapentin 100 mg TID with no relief in her symptoms. Pain complicated by hematoma and subsequent infection and draining left ankle where he also had swelling. In October 1999 he underwent
began after right knee arthroscopy and lateral release for recurrent sinus which eventually healed with scarring three months after injury. repair of torn tendon and ligaments in the ankle. His pain persisted,
right patello-femoral ligament performed 1½ months prior to clinic During her visit to the pain clinic, she had hyperalgeisa, allodynia in and he developed “electric jolts” sensation from heel to toes and foot
visit. After surgery she noted swelling in the right knee and around the the skin overlying the scar and the anterior thigh in the saphenous cramps. He also expressed feeling cold in the left foot. He underwent
surgical scar. Pain was described as sharp primarily in the right knee nerve distribution. She also had numerous muscle spasms and calcaneal lateral osteotomy in July 2000. After surgery some of his
with sensitivity to touch. She also complained of shooting pain going electrical jolts running up and down her thigh. MRI of her right thigh pain in the ankle improved, but he developed increased sensitivity on
down her calf and up to her hip since surgery. In addition there was a showed extensive scar in the medial aspect of the soft tissues about the lateral aspect of the foot. In February 2001 he had sural nerve
burning sensation in the medial aspect of right thigh right leg. On two-thirds of the way down to the bone. Also seen was an area of transected just above the ankle in the hope of pain relief. He
examination she had hyperalgesia, allodynia in the medial aspect of fibrosis which extends near vastus medialis muscle and runs for developed a patch of numbness above the lateral malleolus, but his
right knee in the saphenous nerve distribution. about 4-5 cms. EMG showed normal femoral latency. hypersensitivity and pain persisted with sensitivity to socks and
blankets tracking his foot at night.
A saphenous nerve block in the Hunter’s canal (adductor) with 5 cc of We proceeded with a saphenous nerve block in the Hunter’s canal
0.5% bupivacaine was performed prior to proceeding with a lumbar with 5 cc 0.5% bupivacaine and 20 mg methylprednisolone acetate. Upon examination, hyperalgesia and allodynia on the lateral aspect of
sympathetic block. In addition, a compounded topical cream (AGL: We also prescribed KAGL (ketamine, amitryptiline, gabapentin and the left foot and a patch of numbness behind the lateral malleolous
amitriptyline 5%, gabapentin 3% and lidocaine 5%) was prescribed lidocaine) cream. The patient was seen two weeks later and had mild were noted. He had paraesthesias in the dorsum of left foot. Our
for three times per day. Six days later on return visit, her symptoms relief in allodynia and hyperalgesia in the thigh. Another saphenous tentative diagnosis was CRPS type II of the left foot.
were much improved. A saphenous nerve block with local anesthetic nerve block with 5 cc 0.25% bupivacaine was performed as well as a
and 40 mg methylprednisolone acetate was repeated. scar neuroma injection of 5 cc 0.25% bupivacaine and 20 mg We performed a left sural nerve block near the transected nerve
methylprednisolone acetate. Four-week follow-up, the patient had using a nerve stimulator using 3 cc 0.25% bupivacaine with 40 mg
The patient returned four weeks later with sustained good pain relief significant improvement in her allodynia and hyperalgesia, as well as methylprednisolone acetate. AGL cream was also applied to the skin
until two days prior to return her pain started returned at a lesser improvement in movement of the right knee. Saphenous nerve block at the sensitive spots at home. On return one month later, he had no
intensity. Another saphenous nerve block was administered just with and scar neuroma injection were repeated. Pain relief lasted for pain or hypersensitivity in his foot. He was advised to continue using
4 cc 0.5% bupivacaine and 40 mg methylprednisolone acetate. She several weeks and she also reported better motor function of her right the AGL cream and follow up as needed.
also increased her AGL cream from once a day to three times a day. thigh.
In follow up at 1½ months after initial visit, she reported full relief from
DISCUSSION The CRPS Types I and II as described by
All patients had allodynia and hyperalgesia commonly
the Orlando Consensus Workshop in 1993 1. Abram SE. Neural blockade for neuropathic pain. Clin J Pain
associated with CRPS. All had a history of
2. Nir-Paz R. Saphenous nerve entrapments in adolescents.
edema/warmth or cold sensation (vasomotor changes). CRPS Type I (RSD) CRPS Type II (Causalgia) Pediatrics 01 Jan 1999;103(1):161-3.
As noted by the CRPS Orlando Consensus Workshop 3. Schwartzman RJ. Post injury neuropathic pain syndromes.
1. Type I is a syndrome that develops after an initiating 1. Type II is a syndrome that develops after a nerve
in 1993, a potential cause of symptoms must be ruled noxious event. injury. Spontaneous pain or allodynia – hyperalgesia
Med Clin North Am 01 May 1999;83(3):597-626.
out before diagnosing CRPS I or II. We attempted to occurs and is not necessarily limited to the territory of 4. Reid V. Proximal sensory neuropathies of the leg, Neurol Clin
2. Spontaneous pain or allodynia – hyperalgesia occurs, 01 Aug 1999;17(3):655-67, viii.
exclude neuropathy of saphenous and sural nerves, by the injured nerve.
performing nerve block with local anesthetics and is not limited to the territory of a single peripheral 5. Yaksh TL, Chaplan, SR. Physiology and pharmacology of
nerve, and is disproportionate to the inciting event. 2. There is or has been evidence of edema. Skin blood neuropathic pain. Anesthesiol Clin North America June
steroid. All patients had good prolonged pain relief. flow abnormality or abnormal sudomotor activity in the 1997;15(2).
3. There is or has been evidence of edema. Skin blood region of the pain since the inciting event. 6. Wasner G, Backonja, Baron R. Traumatic neuralgias: complex
flow abnormality or abnormal sudomotor activity in the regional pain syndromes (reflex sympathetic dystrophy and
region of the pain since the inciting event.
CONCLUSION 3. This diagnosis is excluded by the evidence of
conditions that would otherwise account for the degree
causalgia): clinical characteristics, pathophysiological
mechanisms and therapy. Neurol Clin Nov 1998;16(4).
4. This diagnosis is excluded by the existence of of pain and dysfunction. 7. Aeschbach A, Mekhail N. Common nerve blocks in chronic
We conclude that in patients with CRPS like symptoms conditions that would otherwise account for the degree pain management. Anesthesiol Clin North America June
of pain and dysfunction. 2000;18(2).
but predominantly involving single peripheral nerve
8. Stanton-Hicks M. Reflex sympathetic dystrophy: changing
distribution (irrespective of documented nerve injury) concepts and taxonomy. Pain 01Oct 1995;63(1):127-33.
should initially be managed by peripheral nerve blocks 9. Stanton-Hicks M. Complex regional pain syndrome (type I,
with local anesthetic and steroids and adjuvant topical RSD; type II, causalgia):controversies. Clin J Pain 01 Jun
cream applications, prior to resorting to LSB. 2000;16(2 Suppl):S33-40.
Performance of peripheral nerve blocks is relatively
easy and has a lower complication rate as compared to