Surgical Implant Generation Network (SIGN)
A Mission to Egypt

Myles Clough, M.D., FRCSC
Kamloops, BC

In September 2005 I was asked to attend the annual conference of the SIGN project and describe the resources on the Internet which relate to Intramedullary Nailing. This first hand look at the project was fascinating and I was provoked to volunteer for a SIGN mission to Egypt, which took place in November 2005.

SIGN (www.sign-post.org) is the brainchild of Dr. Lew Zirkle, an orthopaedic surgeon from Richland in Washington State. His overseas experience began in 1968 during the Vietnam War. His contact with the people of Vietnam led him to return many times over the next three decades and in the 1980s, he spent a period of time in Indonesia training the first cadre of orthopaedic surgeons in that nation. Revisiting the area some years later he found that the doctors he trained were largely unable to practice the modern methods he taught them because surgical implants were too expensive for the patients to afford. In many developing countries hospitalization is free, or at least affordable, even for the poor. But the patients must pay for treatment in the form of any surgical implants. A turning point came when Dr. Zirkle was shown a man who had spent three painful years in a hospital bed with an un-united fractured femur. The Surgical Implant Generation Network (SIGN) was founded as a charity and Dr. Zirkle researched the possibility of designing and manufacturing affordable implants.

Figures 1a & 1b: AP (a) and Lateral (b) views of a new fracture through an area of malunion in the tibia of a 26-year-old man.

An interlocking tibial IM nail was selected as the most needed implant. The main design challenge was to design a locking system that could be used without fluoroscopic control as a C-arm was another piece of apparatus that many hospitals could not afford. Making the nail solid and rigid enough that the distal interlock can be referenced off the proximal end solved this problem. In 1999 the first four projects in Vietnam and Indonesia were started. Dr Zirkle took a supply of nails to these areas and showed the local surgeons how to use them. They were accepted with enthusiasm and the programme has expanded steadily ever since. There are now more than 100 hospitals in over 40 nations, using SIGN nails. The ideas have had passed both ways. The Vietnamese surgeons soon began to use the implant for femur fractures using a retrograde approach. This prompted some changes in the design of the nail and the same nail design is now used for tibias, femurs and the humerus. A surgeon in Myanmar has been using it for ankle fusion. Because the implant is available at no charge, there is a strong incentive to use it for purposes the designers had not thought of.

The money to manufacture the implants is raised by the SIGN group through charitable donations. The implants are manufactured using a very efficient and cost-effective process; and they are distributed free to hospitals which can prove that needy patients are not being treated because they cannot afford it. Teams of surgeons pay their own way to go out from the USA to teach the technique. At the SIGN conference, it was inspiring to meet these surgeons and hear accounts of their interesting experiences. I was due to attend the Congress of the Egyptian Orthopaedic Association (EOA) and soon found myself committed to taking the SIGN programme to Egypt - the first mission to Egypt and the first SIGN mission led by a Canadian.

My local contact was Dr. Yasser Elbatrawy who is a Lecturer at the Department of Orthopaedics, Alzahra University Hospital in Cairo. He confirmed that the University hospitals have wards full of trauma victims waiting for treatment. The budget for implants was about $10,000 per year; after it has run out, any surgery must be sanctioned by the Ministry of Health, a process which usually takes weeks. I owe a huge debt to Dr. Elbatrawy for his generous hospitality and for all the efforts made by him and the other members of the Departments of Orthopaedics at Alzahra and Al Hussein University Hospitals. After the EOA congress, he took me in charge. We started with a workshop on the technique, followed by case presentations by the residents and a ward round. Templating is an important aspect of the SIGN technique so we spent time getting to meet the patients and measuring on the patients and the X-rays. Next day we did three cases. I had recommended we start with easy cases. This was interpreted rather loosely; our first case was indeed a straightforward tibial fracture which we could reduce closed, but this was soon followed by difficult open reductions. Many of the patients had been in splints or traction for many days and the fractures were overlapped, angulated, rotated and beginning to form soft callus. Over half the cases needed open reductions; this is a common pattern in all the hospitals where SIGN surgeries are performed and is part of the logic of the design. Because the reduction is open, it is not as necessary to use a guidewire, so the rod can be solid and is rigid enough for the locking guide system to reference off the proximal end.

Figures 2a & 2b. Postoperative AP (a) and Lateral (b) views of the tibia after osteotomy and SIGN nail fixation

Over the next few days we performed ten SIGN surgeries in two different hospitals. It was disconcerting to be treated as a visiting professor, the more so because they brought out the most difficult cases. One young man had sustained a compound tibial fracture three years previously; it went on to develop an infected non-union and was treated by the Ilizarov method. The infected portion had been excised, the two fragments docked and the proximal tibia lengthened after a corticotomy. For a variety of reasons the leg had been over-lengthened two centimetres and the fracture site was mal-united. Now he presented with a new fracture through the mal-union site! He flatly rejected the idea of being treated by external fixation again; we planned to osteotomize the fibula, excise the malunion, shorten the bone and align everything over an IM nail. The osteotomies went well, if one discounts the fact that the saw blade was into its 100^th case and the power saw broke in two under the stress. We were able to ream the proximal fragment retrograde to make a passage for the rod but then the case really started. Because of the soft regenerated bone where the tibia had been lengthened, anything introduced antegrade penetrated out the back of the proximal tibia. We had, in the end, to place four blocking screws medial to lateral across the tibia in order to keep the rod inside the tibia. However, eventually all was accomplished and the Egyptian surgical team had learned many new (Anglo Saxon) phrases. The smile on the face of the patient as he left the hospital a few days later is just one of the rewards of this fascinating experience.

SIGN surgery teams have been sent to the front line after the Indonesian tsunami and the Indo-Pakistan earthquake. Dr. Zirkle’s group performed 300 SIGN surgeries in Pakistan following the latter tragedy. The implant is well suited to use in primitive conditions and the technique can be taught quickly. By the end of my stay, the surgeons were doing straightforward tibial fractures in 20 minutes. I ended up with the following conclusions regarding the SIGN system.

1. The SIGN nail is well designed as an implant for tibial fractures. It can be inserted more quickly than conventional IM nails because you don’t need to line up the distal locking holes with the C-arm. It is a lot cheaper than most other systems. It is a disadvantage that one cannot introduce the nail over a guidewire.
2. Canada’s Disaster Assistance Response Team (DART) sends medical assistance to areas which have suffered a natural or man-made disaster. This team could be equipped with SIGN nails and trained to use them.
3. Other Canadian orthopaedic surgeons should do a SIGN mission and introduce the technique to some interesting and exotic part of the world. It was a truly worthwhile experience.
4. SIGN is an orthopaedic charity well worth supporting financially.