A quantitative analysis of two cementing techniques in total elbow replacement: A cadaveric study

One of the reasons for failure of total elbow replacement is loosening of the ulnar component. Cementing techniques are often outdated. A special small nozzle is needed for the ulnar component, when a cement gun is used. This may not always be available, or surgeons may prefer to use a syringe. We postulated that the use of a cement gun and smaller nozzle would result in improved filling of the ulnar canal. A cadaveric study was performed in which the ulnas of paired specimens were cemented with a cement gun or with a syringe. A 3D printed ulnar component was inserted and computed tomography scanning was performed on all specimens. Filling of the ulnar intramedullary canal was analysed using 3D reconstructions of the specimens. A greater degree of filling was seen by the use of the cement gun in 85.7%. Filling was 52.7% in the syringe group (25.1–78.7%), compared to 63.3% for the cement gun group ( p < 0.05). The use of a small nozzle cement gun provided a significantly higher filling degree of the ulnar canal. We recommend to always use a cement gun with a specific small nozzle to cement the ulnar component in total elbow arthroplasty.

Modified hybrid cementing technique reduces stem tip pain and improves patient’s satisfaction after revision total knee arthroplasty

Background There have been no studies comparing patient-reported outcome measures including end-of-stem tip pain and patient satisfaction based on the use of cementing techniques in revision total knee arthroplasty (TKA). The purpose of this study was to compare end-of-stem tip pain and PROMs with hybrid and modified hybrid cementing techniques in revision TKAs. Method Sixty-two cases of revision TKA performed by a single surgeon were divided into two groups based on the cementing technique with a minimum follow-up of 2 years. Two types of cementing technique for femoral and tibial stems were used as follows: (1) a hybrid cementing technique (33 cases), in which cement was applied immediately distal to the modular junction of the stem and the component while the distal stem was press-fitted into the diaphysis without using cement; and (2) a modified hybrid cementing technique (29 cases), in which cement was applied to the tip of femoral and tibial stems. The thigh and shin were assessed for the end-of-stem tip pain. Patient satisfaction was evaluated based on the satisfaction items of New Knee Society Score. Results Modified hybrid cementing significantly lowered the percentage of patients manifesting shin pain (3.4% vs. 24.2%, p = 0.029). Patients treated with the modified hybrid cementing technique showed a higher satisfaction rate (p = 0.003). Multivariate logistic regression analysis showed an increase in the odds of satisfaction 32.686-fold (p = 0.004) in patients without pain at the end-of-stem tip in the shin and 9.261-fold (p = 0.027) in patients treated with the modified hybrid cementing technique. Conclusion The modified hybrid cementing technique for fixation of long-stem in revision TKAs reduced the end-of-stem tip pain in the shin, leading to significantly higher satisfaction compared with the hybrid cementing technique after revision TKA. Level of evidence Level III

Current concepts and outcomes in cemented femoral stem design and cementation techniques: the argument for a new classification system

Cemented implant fixation design principles have evolved since the 1950s, and various femoral stem designs are currently in use to provide a stable construct between the implant–cement and cement–bone interfaces. Cemented stems have classically been classified into two broad categories: taper slip or force closed, and composite beams or shaped closed designs. While these simplifications are acceptable general categories, there are other important surgical details that need to be taken into consideration such as different broaching techniques, cementing techniques and mantle thickness. With the evolution of cemented implants, the introduction of newer implants which have hybrid properties, and the use of different broaching techniques, the classification of a very heterogenous group of implants into simple binary categories becomes increasingly difficult. A more comprehensive classification system would aid in comparison of results and better understanding of the implants’ biomechanics. We review these differing stem designs, their respective cementing techniques and geometries. We then propose a simple four-part classification system and summarize the long-term outcomes and international registry data for each respective type of cemented prosthesis. Cite this article: EFORT Open Rev 2020;5:241-252. DOI: 10.1302/2058-5241.5.190034

Femoral Cementation in Knee Arthroplasty—A Comparison of Three Cementing Techniques in a Sawbone Model Using the ATTUNE Knee

Femoral component loosening is a rare but severe complication in total knee arthroplasty. Former studies have repeatedly demonstrated radiolucent lines behind the ventral and dorsal anchoring shields of the femoral components, which has led us to investigate this matter further. Therefore, three different cementing techniques were tested in a group of nine Sawbone samples each. These differed in the amount of cement applied on the femoral component as well as in the pressure application. Computed tomography was performed to evaluate and classify the cement penetration into the bone adjacent to the prosthesis according to the zones defined by the Knee Society scoring system. The results show significantly deeper cement penetration in all zones when a pressurizer is used. In the other two groups, no significant difference in the dorsal bevel cement penetration was noted. Additionally, no difference in ventral and dorsal cement penetrations (Zones 1 and 4) was delineated. In contrast, there was a significant difference in both the ventral bevel (Zone 2) as well as the distal anchoring surface (Zones 5–7). The use of a pressurizer results in greater cement penetration into all anchoring areas. Completely covering the component back surface results in a significantly higher penetration, which is mainly due to differences in volume. These data show significantly improved cementation results when using a pressurizer. Whether this improves the biomechanical properties and ultimately the revision rate requires further investigation.

Comparing Cementing Techniques in Total Knee Arthroplasty: An In Vitro Study

Aseptic loosening remains to be a major reason for revision in total knee arthroplasty. Cement penetration of 2 to 5 mm increases the interface strength and consequently decreases the likelihood of loosening. But despite this overall accepted optimal cement penetration, there is still a wide variety of cementing techniques used in total knee arthroplasty. The purpose of this study was to evaluate two cementing techniques on the tibial and femoral sides, with regard to cement penetration. Five paired cadaveric knees were used. A total knee arthroplasty was placed according to standard practice, with a setup that mimics the clinical practice. On the tibial side, we compared the application of cement to the bone surface alone, to the application of cement to both the bone surface and the component. On the femoral side, we compared the application of cement to the posterior condyles of the component and to the anterior and distal parts of the bone surface, to the application of cement to the component alone. After the cement had cured, the arthroplasty was removed and the bone was examined to determine the cement penetration using digital software. When applying cement to both the tibial bone surface and the tibial component, the cement penetration increased compared with applying cement to the tibial bone surface alone (3.46 vs. 2.66 mm, p = 0.007). With regard to the distal femoral cuts, the cement penetration did not vary when applied to either the bone or the component (2.81 vs. 2.91 mm). But applying it to the anterior bone surface did seem preferable, when compared with only applying it to the component. The average cement penetration did not differ, but applying the cement to the bone did enlarge the total length of the cement distribution (2.48 vs. 0.96 mm, p = 0.011). Almost no cement was detected on the posterior surface of the femoral cut. We concluded that applying cement to both the tibial bone surface and the component improves cement penetration.