Floor plan - 2013 Annual Meeting - American Association for Hand ...

Soleus Arch as Compression Site for Proximal Tibial Nerve: Cadaver Study
Institution where the work was prepared: Union Memorial Hospital, Baltimore, MD, USA
Eric H. Williams, MD; Dellon Institute for Peripheral Nerve Surgery: Baltimore. Clinical Instructor; Johns Hopkins
University School of Medicine; Gedge D. Rosson, MD; Johns Hopkins School of Medicine; A. Lee Dellon, MD; Dellon
Institute for Peripheral Nerve Surgery: Baltimore. Professor; Johns Hopkins University School of Medicine
TITLE:
Soleus Arch as Compression Site for Proximal Tibial Nerve: Cadaver Study
PURPOSE:
As the Pronator Syndrome represents a site of proximal compression of the median nerve that can be symptomatic by itself or be the
etiology of ìfailed carpal tunnel syndromeî, so too may a site of proximal compression of the tibial nerve beneath the aponeurotic arch
of the origin of the soleus muscle be a source of symptoms for patients with pain in the calf or who complain of pain or numbness in
their toes. The setting for the syndrome of proximal compression of the tibial nerve may be in patients with previous lumbosacral spine
surgery, ìfailed tarsal tunnel syndromeî, compartment syndrome, of it may exist on its own.
METHOD:
25 limbs from 18 embalmed cadavers were dissected using 3.5X loupe magnification. There were 12 right and 13 left cadaver limbs; the
sex was unknown. The distance from the medial femoral epicondyle to the soleus arch and the length of the leg was measured. The
ratio of limb length to location of the soleus arch was calculated. The thickness of the fibrous soleus arch, its relationship to the tibial
nerve, and any narrowing of the tibial nerve in this location were noted.
RESULTS:
The average limb length was 46.8 cm (40-55 cm). The tibial nerve traveled under the soleus arch 9.4 cm (7-13 cm) below the medial
femoral epicondyle. This location measured approximately 1/5 the total length of the leg. The soleus arch demonstrated a thick deep
layer of fascia in 64% of the specimens. The tibial nerve was narrowed in 52% of the specimens; 48% demonstrated slight narrowing
over several centimeters, but 4% demonstrated a tight focal constriction across the nerve at the level of the soleus arch.
CONCLUSION:
The soleus arch represents an anatomic site of potential compression of the proximal tibial nerve.
Anatomical Landmarks for the Nerve Branch to the Masseter Muscle in Facial Reanimation
Institution where the work was prepared: SIU School of Medicine, Springfield, IL, USA
Nada Berry, MD1; Margo Herron1; Rebuen Bueno1; Ronald Zuker, MD2; Michael W. Neumeister3; (1)SIU School of
Medicine, (2)The Hospital for Sick Children, (3)Southern Illniois University School of Medicine
The nerve branch to the masseter muscle has been used as the donor nerve in facial reanimation surgery for the Moebius syndrome
patient. It is located on the undersurface of the masseter usually coursing downward at the posterior margin of the muscle below the
zygomatic arch. As the nerve enters the muscle, it divides into smaller branches. An anatomical study has not been done to map out
the location and course of the nerve as in enters the muscle. This study defines the course of the nerve in relation to anatomical landmarks
and measures the length of the nerve before branching. Total of 15 nerves were dissected and examined. The following landmarks
were selected: superior pole of the tragus, point A at superior border of the zygoma, oral commisure, and the first branch emerging
from the muscle. The average length from the tragus to point A is 29.4mm (STD 3.4), and the average distance to the first branch
is 18mm (STD 2.1). When using the nerve branch to the masseter muscle as the donor nerve for reanimation with a reinnervated gracilis
muscle, the results from this study will help identify the nerve during the reanimation procedure.
Novel Model for End-Neuroma Formation in the Amputated Rabbit Forelimb
Institution where the work was prepared: Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
Peter S. Kim, MD1; Kristina O'Shaughnessy, MD1; Todd A. Kuiken, MD, PhD2; Gregory A. Dumanian1; (1)Northwestern
University, Feinberg School of Medicine, (2)Rehabilitation Institute of Chicago
The forelimb amputee poses many reconstructive challenges in the clinical setting, and there is a paucity of established surgical models
for study. To further elucidate the pathogenic process in amputation neuroma formation, we created a reproducible, well-tolerated
rabbit forelimb amputation model. Upon approval from the institutional Animal Care and Use Committee, 5 New Zealand white rabbits
underwent left forelimb disarticulation. During this initial surgery the median, radial and ulnar nerves were transected 1.6-2.5 (mean
2.0) cm distal to the brachial plexus, transposed onto the anterior chest wall and preserved at length. Six weeks subsequent to the
amputation, the distal 5 mm of each neuroma was excised and the remaining stump underwent histomorphometric analysis. The nerve
cross sectional areas increased by factors of 1.99, 3.17, and 2.59 in the median (p=0.059), radial (p=0.001) and the ulnar (p=0.012) nerves
respectively. At the axonal level, the number and cross sectional area of axons demonstrated an inverse relationship whereby the number
of axons in the median, radial and ulnar nerves increased by factors of 5.13 (p=0.096), 5.25 (p=0.037) and 5.59 (p=0.046) and the
cross sectional areas of the axons decreased by factors of 4.62 (p