Author's Reply: Developing a Sustainable HIP Service in Cambodia

Dear Editor,

Dr Dossche raises some interesting questions about our paper “Developing a sustainable hip service in Cambodia” (1) and we hope our following remarks will help him with his work in a similar environment (2).

The implant manufacturer of the fractured stems is an Indian company, presumably copying a western brand, but using local materials and selling them for about $300 which is relatively affordable in the developing world. After breakage of the first stem, we wrote to the company informing them of the fact, but they replied that no similar report had been made. Once another 2 stems had failed however, we reported again and the stems were removed from the market. A subsequent femoral implant was no doubt made from the same materials, but the design changed and there have been no further breakages in the new design. Other orthopaedic implants from this manufacturer had been analysed in a university metallurgy department, and reported as being acceptable as they were equivalent to older generations of implants used in the developed world. We do not want to name the manufacturer, as we do not want to damage their business, and we continue to rely on their products.

As far as the learning curve was concerned, 2 of the local surgeons were very experienced generally, and had already had experience of operating on broken hips for some years, so when a foreign surgeon brought modern American hip replacement prostheses, it took him only 2 visits of 1 week each to teach the 2 local surgeons how to do the operation independently. He and other expatriate surgeons continued, and still continue, to visit over the next few years, and the local expertise grew with each visit, but the supply of prostheses was not reliable until the Indian supplier was enrolled.

Loss to follow-up is a problem in all developing countries, and we would not disagree that the 15 patients could be excluded from further analysis.

The Harris Hip Score was chosen as we wished to compare our data to a similar programme in Malawi, as this was the only other reported data on a similar patient cohort. We found it to be difficult to administer by phone, as Dr Dossche points out, so we have supplanted it with the Oxford Hip Score.

The average age of the patients is indeed quite young, which reflected the philosophy of trying to keep young arthritic patients mobile and capable of working so that they could earn a living, and establish families. Obviously, the revision burden would thereby be increased, but this is a necessary disadvantage which is greatly outweighed, in our opinion, by having a chance in life while still young, and a potentially failed hip being converted to a hip fusion can be put off for a decade or more.

Introduction of total hip replacement (THR) into this setting is difficult, but not necessarily more so than when it was first introduced by John Charnley, and we feel that the benefits to the patients have been substantial, while the downside has not discouraged patients from returning for a THR on their other hip in bilateral arthritic cases. We, therefore, would encourage Dr Dossche and his colleagues to build up such a service in a similar setting. We would highly recommend putting resources in place to follow up these patients actively, and enter data prospectively, in order to identify and address the inevitable problems early.