Only one clinical study is published so far comparing the failure rate of intertrochanteric fractures treated with a DHS with and without cement augmentation. A beneficial effect of the augmentation was noticed on the stability of the construct [22].

The PFNA augmentation set, allowing for augmentation through the helical blade, became available very recently. Only a few publications are available until now. One study on foam models mimicking osteoporotic bone could show an increased cut-out resistance of augmented PFNA helical blades. In the group of samples where the helical blade was inserted in an eccentric and thus biomechanically inferior position, this effect was even accentuated [27]. In two other biomechanical studies, augmentation of PFNA helical blades was performed in osteoporotic cadaveric bones. In the first study, a superior rotational stability and enhanced pull-out resistance was found in the augmented group [28]. The second study showed an increased cut-out resistance of the augmented femoral heads [25]. In both studies, it was noticed that the benefit of augmentation was higher in bones of low mineral density as measured by micro-CT. Similar findings were observed for augmented lag screws in cadaveric bones [21].

Only one clinical study on the use of PFNA augmentation is published so far [36]. In this multicenter study, 59 patients with a pertrochanteric hip fracture were treated with a PFNA with augmented helical blades. Only one intra-operative complication occurred: a perforation of the femoral head by the Kirschner-wire, which was detected by the leakage test. In all other patients, augmentation of the helical blade was performed with a mean amount of 4.2 ml of cement. The radiographic appearance of the cement distribution was set as secondary outcome parameter. It was noticed that only in case of severe osteoporosis, the cement showed a distribution towards the subchondral area. The postoperative results were very promising: all fractures showed callus formation, no osteonecrosis of the femoral head or lysis around the blade was noticed and no implant migration like cut-out or cut-through was seen. The data suggest that the rate of complications directly related to implant augmentation is very low when the technique is applied correctly. Functional recovery was very good with half of the patients reaching their prefracture mobility level (Fig. 17.5a, b). An important limitation of the study is the short follow-up time of 4 months on average only. Nevertheless, it is known that most implant-related problems after hip fracture osteosynthesis occur in the first postoperative months. In one case, blade removal became necessary due to a new fracture at the nail tip. This blade removal could easily be performed because the interface of the blade and the PMMA cement broke, similar to the cadaver studies.

As there is ongoing debate on the benefit of augmentation, a new prospective randomised comparative trial will be conducted to evaluate the influence of proximal femoral nail augmentation on the functional recovery of the patients [37].

Until now, it remains unclear how to identify the best indications for augmentation. The decision which patient will benefit from the procedure still depends on the personal subjective judgment of the surgeon. An intra-operative measuring device to determine the local bone quality may become the solution for this problem.