**4. THR for failed neck of femur internal fixation**

revision surgeries) are higher in the long term [35]. Maceroli et al. demonstrated lower mortality rates in patients undergoing THR for femoral neck fractures in centres that performed large numbers of such procedures [36]. Uhler et al. demonstrated that a patient will gain more cumulative utility over the course of 2 years by waiting 48 hours for a THR, despite an increase in short-term morbidity associated with delayed surgery [37]. It seems reasonable therefore to advocate THR for suitable patients where dedicated arthroplasty services are available. **Figure 1** demonstrates a left basicervical neck of femur fracture, with subsequent

treatment with a hybrid THR shown in **Figure 2**.

88 Total Hip Replacement - An Overview

**Figure 2.** AP pelvis demonstrating subsequent treatment with a hybrid THR in the acute setting.

**Figure 1.** AP radiograph of pelvis showing left basicervical neck of femur fracture.

Following initial treatment with internal fixation, the neck of femur fractures may develop nonunion and osteonecrosis, with reoperation rates of up to 40% reported in the literature. Nikolopoulos et al. demonstrated in a prospective study that patients with displaced neck of femur fractures who underwent internal fixation had a higher rate of avascular necrosis than those that were undisplaced [38]. This group of patients may develop disabling secondary degenerative symptoms necessitating arthroplasty. We highlight this with examples of clinical cases. **Figure 3** shows the collapse of the femoral head following initial sliding screw fixation of a basicervical neck of femur fracture. This was subsequently revised to a hybrid THR as demonstrated in **Figure 4**. **Figure 5** describes the case of screw cut-out post ORIF of the neck of femur fracture, which was subsequently revised to a modular prosthesis as seen in **Figure 6**.

Tidermark et al. demonstrated suboptimal outcomes in patients with displaced neck of femur fractures treated with internal fixation, showing impaired functional outcomes when compared with a cohort of undisplaced fractures despite radiographic and clinical evidence of union [39].

In treating nonunion the surgical team must consider the presence of infection. Clinical evaluation and serial erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels are useful diagnostic tools and if abnormal might prompt joint aspiration or bone biopsy and culture. If preoperative or intraoperative findings suggest infection, a two-stage revision with removal of metalwork and excision of the femoral head is usually performed. An antibioticimpregnated spacer is implanted in the first instance, and subsequent arthroplasty is performed at an appropriate later date.

**Figure 3.** AP radiograph of pelvis demonstrating collapse of femoral head post dynamic hip screw fixation of basicervical neck of femur fracture.

**Figure 4.** Demonstrating subsequent revision to hybrid THR following failed internal fixation.

During the preparation of the femur, it is recommended to leave the internal fixation device in situ and to avoid excessive traction and leg rotation until dislocation to minimise the risk of intraoperative fracture. Cemented or uncemented components can be used depending on user preference and in conjunction with intraoperative evaluation of acetabular and femoral

Arthroplasty for Proximal Femur Fracture http://dx.doi.org/10.5772/intechopen.77053 91

In such cases the acetabulum may not be degenerative and thus less sclerotic than usually encountered in elective arthroplasty. Reaming therefore should be performed with caution, being mindful of the risk of medial wall penetration. In performing a THR in a cognitively impaired patient, an extended stability or constrained liner and a larger diameter bearing

Patients with failed internal fixation of intertrochanteric fractures present with significant functional disability and pain. In these patients revision of the fixation device will often be considered as a first option, but these surgeries are often complicated by bone loss and the presence of avascular bone at the nonunion site. Hip arthroplasty offers a good salvage option for selected patients as it obviates the need for fracture healing and establishes immediate skeletal continuity allowing early, progressive weight bearing. **Figure 7** shows a nonunion of a subtrochanteric femur fracture following cephalomedullary fixation which was successfully

Technical issues such as difficulty of implant removal, bone loss, trochanteric nonunion, anticipated haemorrhage and suboptimal bone quality must be considered. A common mode of

**5. THR for failed intertrochanteric fracture fixation**

**Figure 6.** Demonstrating subsequent revision to a modular prosthesis.

revised to a modular THR as seen in **Figure 8**.

bone quality.

should be considered.

**Figure 5.** AP radiograph demonstrating screw cut out of post ORIF of neck of femur fracture.

Preoperative templating, paying particular attention to the length of the proposed femoral component is essential to bypass bone defects or screw tracks. An attempt should be made to recreate the patients' normal anatomy; it is essential to restore offset, length, and centre of rotation. If acetabular bone loss is noted as autogenous bone graft, allograft or a fixation device may be necessary to reconstruct or span a marginal, cavitary, or combined defect.

**Figure 6.** Demonstrating subsequent revision to a modular prosthesis.

During the preparation of the femur, it is recommended to leave the internal fixation device in situ and to avoid excessive traction and leg rotation until dislocation to minimise the risk of intraoperative fracture. Cemented or uncemented components can be used depending on user preference and in conjunction with intraoperative evaluation of acetabular and femoral bone quality.

In such cases the acetabulum may not be degenerative and thus less sclerotic than usually encountered in elective arthroplasty. Reaming therefore should be performed with caution, being mindful of the risk of medial wall penetration. In performing a THR in a cognitively impaired patient, an extended stability or constrained liner and a larger diameter bearing should be considered.
