Brian P. Jacob, David C. Chen, Bruce Ramshaw, Shirin Towfigh (eds.) - The SAGES Manual of Groin Pain-Springer International Publishing (2016)

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P. Vahedifar and E. Kamrava
Topical Medication
Topical medications have shown efficacy in the treatment of
neuropathic pain in those with diabetic and postherpetic neuralgia.
This treatment may be an intuitive approach in treating allodynia and
hyperalgesia at the affected area. Robbins et al. reported significant
efficacy in patients with CRPS using large doses of topical capsaicin [ 16 ].
Davis et al. studied the topical use of clonidine to relieve the localized
hyperalgesia in patients with sympathetically mediated pain, with favorable
results [ 17 ]. Similarly, topical ketamine use as described by Finch
et al. has been effective in reducing symptoms of allodynia among
patients with CRPS [ 18 ].
Intravenous Medications
Several forms of intravenous medication have shown promise in the
treatment of CRPS. There are a number of controlled studies on bisphosphonate
such as pamidronate, alendronate, and clodronate, all of which
have shown considerable improvement in pain with patients with
CRPS. Also, intravenous use of ketamine in the treatment of CRPS has
shown a significant reduction in allodynia [ 19 , 20 ]. Other intravenous
medications such as lidocaine as demonstrated by Wallace et al to have
shown to help decrease pain in patients with CRPS types I and II [ 21 ].
Interventional Therapy
Interventional therap ies have been used in conjunction with manual
and physical therapy as well as behavioral therapy in order to reduce
pain and increase the likelihood of positive outcomes. These treatments
should not be used in the absence of multimodality treatment and should
not be started if there is no improvement with physical therapy.
Interventional therapies are best used as an adjunctive treatment to
decrease pain and to allow faster improvement in symptoms. One such
therapy, sympathetic nerve blockade, has been historically used among
those with CRPS as a diagnostic and therapeutic intervention to alleviate
pain. Several studies have shown a reduction in sympathetically
mediated pain with this blockade [ 22 ]. These nerve blocks should be
continued as long as they provide improvement. If the effect of the