Knee Prosthesis in the Computer Era

Over the past two decades, computer assistance has revolutionalized surgery and has enabled enormous advancements in knee prosthesis surgery. Total knee arthroplasty (TKA) is a hot topic of orthopaedic research. Reflecting population dynamics, its use continues to increase, especially in high demand populations. Therefore, efforts to achieve the best fit and precise alignment in TKA continue. Computer assistance is valuable for knee prosthesis surgeons in this regard. This manuscript investigated the use of computer assistance in knee prosthesis surgery. The effects of computer use on important facets of knee prosthesis surgery, such as precision, clinical aspects, and costs, were examined. Moreover, an overall review of the recent literature on the navigation and personalized cutting guides was conducted.

Managing a pessary business

In this final article in a series of three, components of pessary fitting, provision, and follow up are reviewed from a business perspective related to supplies, patient flow, billing, and coding.

The benefits of customized patient instrumentation to lower-volume joint replacement surgeons: results from practice

Because of the significant risks associated with component malalignment, considerable resources are being utilized to develop technology to improve alignment and decrease outliers in knee replacement surgery. While computer-assisted surgery is more accurate and allows for decreased outliers when compared to traditional instrumentation, it is not a technology that can be utilized by all surgeons who perform total knee arthroplasty (TKA) due to increased operative times and cost. Recently, the creation and use of patient-customized cutting guides has been applied to TKA. Published studies and results from practice have shown customized patient instrumentation technology to have comparable or better implant alignment than traditional instrumentation and increased efficiency with regard to surgical preparation time, the amount of surgical instrumentation needed, and cost savings. For lower-volume/inexperienced surgeons, these advantages can be significant.

Customized patient instrumentation for total knee arthroplasty: preoperative planning and intraoperative technique

Individual physicians are challenged to decrease their operating costs at the same time they are expected to reduce complication rates. For the orthopedic surgeon who performs total knee arthroplasty (TKA), one way to address operating costs is to increase efficiency in the operating room. Computer-assisted surgery (CAS) has not delivered efficiency the way it was once hoped. Customized patient instrumentation (CPI) takes advantage of computer-based technology but, unlike CAS, does not increase surgical time, does not require a computer in the operating room, and allows critical alignment decisions to be made before entering the operating room. In this article, the preoperative preferences and intraoperative techniques in using CPI technology are described. Keeping in mind key components of the intraoperative technique when using CPI, such as soft tissue removal, especially at cutting block contact points, will ensure successful procedures for both the surgeon and patient.

Comparison of á priori alignment techniques for transtibial prostheses in the developing world – pilot study

PURPOSE

The purpose of this study was to evaluate three alignment systems based on two alignment theories that can be utilized in the fabrication of monolimb prostheses that have acceptable alignment. A second goal was to assess the feasibility of technology transfer for providing prosthetic services to remote areas of landmine-affected countries.

METHOD

Five prosthetists and five healthy transtibial amputees participated in the study. Each prosthetist was trained and then used each of the three systems to capture alignment measurements for one subject. Three monolimbs identified as X, Y and Z were fabricated for each subject and assessed during clinical static and dynamic gait conditions. Training materials and methods were also evaluated.

RESULTS

All three systems captured acceptable alignments fairly well, although the two systems that incorporated weight-bearing into the alignment process had slightly better outcomes. Each system has its own advantages in terms of ease of use, required equipment, and ease of technology transfer.

CONCLUSION

All three systems have the potential for application in outreach prosthetic services and warrant continued evaluation. Minor changes need to be incorporated into the alignment systems and procedures to make them easier to use and more effective.

A simple and inexpensive splint for phalangeal fractures

This article describes the fabrication and application of a simple and inexpensive splint for treating phalangeal fractures.

Gait, cost and time implications for changing from PTB to ICEX sockets

The ICEX system (Ossur, Iceland), allows a socket to be manufactured directly onto the stump and is thought to provide improved comfort due to better pressure distribution whilst being easier to fit and manufacture. The aims of this project were to a) compare gait performance by measuring several gait characteristics, b) compare production and fitting times, c) investigate financial implications and d) attempt to gauge the amputees' subjective opinions of socket comfort. A randomised, controlled trial was conducted on 27 trans-tibial amputees with an existing patellar tendon bearing (PTB) socket on the Endolite system (Chas A. Blatchford, UK). Twenty one (21) subjects completed the study. Of these, 10 in the control group received new PTB sockets while 11 in the experimental group received ICEX. Gait analysis wearing existing sockets was performed and kinetic data obtained from a force plate. This was repeated with the new sockets after a 6 week period of adjustment. Mann-Whitney tests were used in statistical evaluations with a significance level of 5%. Subjects were asked to score their prosthesis for comfort using the Socket Comfort Score (Hanspal et al., 2003) and the frequency of visits for socket adjustments over a three-month period post-delivery of the sockets was recorded. This study demonstrates no significant difference in any of the gait parameters measured. Though the time required to manufacture a PTB prosthesis was found to be considerably longer than the ICEX, the overall cost for producing the ICEX was significantly greater. Subjects showed only minor comfort preference for the ICEX design and there was no significant difference in the mean number of visits for socket adjustments. In view of the considerable additional cost of providing ICEX and the lack of evidence of improvement in any parameter tested, the routine provision of ICEX prostheses to unselected trans-tibial amputees cannot be recommended.