A study by researchers at Hospital for Special Surgery (HSS) challenges a widely held belief that long nerve grafts do poorly in adults with an axillary nerve injury. Investigators found that the outcomes of long nerve grafts were comparable to those of modern nerve transfers. Both procedures restored function. The axillary nerve supplies the deltoid muscle of the shoulder and an important rotator cuff muscle. It's part of the brachial plexus, a network of nerves that runs down from the neck and across the shoulder.
"Conventional wisdom is that grafts longer than seven centimeters (about three inches) don't work well. We set out to test this theory and found that long nerve grafts did work well. Our study concludes that this type of graft should not be overlooked as an effective treatment for an axillary nerve injury," said Dr. Scott W. Wolfe, lead author and director of the Center for Brachial Plexus and Traumatic Nerve Injury at Hospital for Special Surgery in New York City.
The study, titled, "Comparison between Long Nerve Grafts and Nerve Transfers for Axillary Nerve Injuries," will be presented at the annual meeting of the American Academy of Orthopaedic Surgeons on March 22 in Chicago.
Injury to the brachial plexus can be devastating, leaving people unable to use their arms or hands. The most common cause is a motor vehicle accident or sports injury. The Center for Brachial Plexus and Traumatic Nerve Injury (http://www.hss.edu/BrachialPlexusCenter) at Hospital for Special Surgery offers advanced diagnostic and treatment options, including complex nerve reconstruction surgery.
Nerve reconstruction is considered when nerves are so severely damaged they cannot recover on their own. These complex operations can take up to 12 hours. Surgeons reconstruct nerves either by bridging a nerve defect with a nerve graft or by performing a nerve transfer from a nearby healthy nerve to share its function. In the study, researchers compared these two different techniques to reactivate the deltoid muscle and enable patients to regain the use of their arm.
"A nerve transfer takes a working nerve from one muscle and transfers all or part of that nerve to a non-working nerve or another muscle, so that the two muscles can share the nerve and regain function," Dr. Wolfe explained. "A nerve graft involves taking a nerve from another part of the body. The nerve is removed from a location where its function is less important, usually the leg, and moved to the damaged area. It is used to bridge the defective gap between two ends of a nerve to restore function."
Only 150 to 200 highly specialized surgeons worldwide perform these complex brachial plexus surgeries, and Dr. Wolfe and his colleagues aim to raise awareness that the procedures can restore function in people severely debilitated by a nerve injury. It is important for patients to be treated in a timely manner.
Traditionally, nerve grafts longer than seven centimeters have demonstrated worse outcomes than short grafts and poorer functional outcome when compared to nerve transfer surgery. The purpose of the HSS study was to take another look at longer grafts and directly compare the outcomes to nerve transfers. The results were measured by the patients' recovery and by a test called electromyography, or EMG. This sophisticated test is used to objectively measure muscle and nerve function.
In the study, 11 patients treated with long nerve grafts (> 7cm, range 9cm to 15cm) were compared with 14 patients treated by a nerve transfer over a 10-year period. The average length of the nerve graft was 13cm (5.2 inches). Data was collected at regular intervals, beginning pre-operatively and continuing for up to 11 years.
Prior to surgery, all patients had EMG tests that showed complete absence of deltoid muscle function. After surgery, deltoid recovery, range of motion and EMG evidence of restored function were compared.
The study found no statistically significant differences in shoulder strength, range of motion or electromyographic recovery between nerve graft and nerve transfer patients. All adults in the long nerve graft group regained at least enough strength to be able to move their arm against gravity, but there were two failures in the nerve transfer group. "Going from no function with a limp and numb arm to gaining enough strength to be able to lift a glass to one's lips is a major gain for these patients," said Dr. Wolfe, who is also chief emeritus of the Hand and Upper Extremity Service at HSS. .
"Improvements in the patients receiving a nerve graft were identical to improvements in the nerve transfer group," he added, "so now surgeons can say with confidence that 'a long graft has a good chance of working,' instead of abandoning the procedure when a nerve transfer is not an option."
Unfortunately, some patients suffer long-term impairment from nerve injuries that could have been repaired because many physicians are unaware that nerve reconstructive surgery works, according to Dr. Steve K. Lee, director of research at the Center for Brachial Plexus and Traumatic Nerve Injury. "When a nerve that controls a muscle loses function, it needs to be reactivated within about 12 months, before the muscle atrophies. Studies have shown that if nerve reconstruction surgery is done within six months after a nerve is damaged, patients do much better."
Dr. Joseph Feinberg, who is co-medical director of the Center and performs diagnostic testing to evaluate nerve injuries, says studies such as the one conducted at HSS are important to raise awareness. "In general, many people feel that these types of nerve injuries are permanent and not many treatments are effective. We want people to be aware that they do have options. Procedures can be done to restore function, even when a patient has completely lost the ability to use certain muscle groups," said Dr. Feinberg, who is physiatrist-in-chief at Hospital for Special Surgery.
Dr. Wolfe says the next step will be to conduct a rigorous multi-center study to better define the role of nerve grafts versus nerve transfers and how best to use the two techniques.
Other contributing authors from Hospital for Special Surgery are Parker Johnsen, B.S., who is the presenting author, and Adele Mirbey, B.A.Paper: Comparison between Long Nerve Grafts and Nerve Transfers for Axillary Nerve Injuries, (Paper 801)
Friday, March 22, 2013, 4:36 p.m. – 4:42 p.m. CDT. McCormick Place, Room N426.About the Center for Brachial Plexus and Traumatic Nerve Injury
Phyllis Fisher | EurekAlert!
Multi-year study finds 'hotspots' of ammonia over world's major agricultural areas
17.03.2017 | University of Maryland
Diabetes Drug May Improve Bone Fat-induced Defects of Fracture Healing
17.03.2017 | Deutsches Institut für Ernährungsforschung Potsdam-Rehbrücke
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy