Muscle biopsie for Acute Complex Regional Pain Syndrome Type I from one extremity for mitochondrial research

Complex Regional Pain Syndrome (CRPS) is a potentially incapacitating syndrome,
that may occur after a minor injury or an operation applied to a limb. CRPS has
impact on all tissues and may impair all functions of that extremity, leading
to severe disability and almost intractable
pain. The spectrum of symptoms and signs is wide. The early phase is
characterized by signs and symptoms of inflammation including excessive pain
and impaired motor and sensory function. The late phase is characterized by
trophic changes of all tissues. In approximately 10 percent of the cases CRPS
occurs without a preceding trauma. Formerly CRPS was denominated as causalgia,
algodystrophy, Sudecks atrophy or reflex sympathetic dystrophy. In 1994 the
International Association for the Study of Pain (IASP) coined the term Complex
Regional Pain Syndrome type I (CRPS I). In CRPS type II (causalgia) nerve
damage must be present.

In patients with acute CRPS I, our department found significantly elevated
SvO2 levels, obtained from the vena cubiti or vena femoralis in the affected
extremity, as compared to samples obtained from the unaffected contralateral
limb and as compared with healty volunteers.
We conclude from these data that the high SvO2, which suggests defective oxygen
metabolism, cannot fully be explained by an oxygen diffusion problem. We
therefore hypothesizedthat the high SvO2 found may also be due to defective
oxygen utilization at the mitochondrial level.

We therefore studied mitochondria in affected muscle tissue from amputated
limbs of CRPS I patients. We observed that mitochondria obtained from CRPS I
muscle tissue displayed reduced mitochondrial ATP production and substrate
oxidation rates in comparison to control muscle tissue. It remains to be
established if the mitochondrial dysfunction that is apparent at the end-stage
of CRPS I is also present in earlier stages of the disease, or are secondary to
CRPS I. The observation of a reduced mitochondrial energy production combined
with reactive oxygen species induced damage in muscle tissue from CRPS I
patients warrants further studies into the involvement of mitochondrial
dysfunctioning in the pathophysiology of CRPS I.

Therefore we are interested to study the mitochondrial energey production
system in patients with acute CRPS I of the lower extremities by means of
muscle biopsy. The contra lateral not involved extremity may function as
control value.

Does mitochondrial dysfunction play an important role in the pathofysiology of
patients with Complex Regional Pain Syndrome Type I ?

Patient inclusion period of 12 months, in total six patients are included

Analysis of data: 6 months

Presentation and publication in an peer reviewed English Journal

Muscle biopsie is an accepted method for analysis and diagnosis of muscle
disorders