Cement (polymethyl methacrylate) has been used in contemporary total hip arthroplasty (THA) since it was originally pioneered by Sir John Charnley in the 1960s. Although the use of polymethyl methacrylate cement was central to the early success of THA, it was subsequently thought to be the weak link, leading to failure. Cemented implant failures were erroneously attributed to “cement disease,” which in reality was attributable to early-generation polyethylene wear and associated periprosthetic osteolysis. That era led to the rise of the use of cementless or porous metal press-fit fixation implants in THA, especially in the United States.¹ Although the uncemented press-fit technique has proven to provide durable osteointegration with low revision rates, its presumed superiority over cemented femoral stems is not supported by peer-reviewed literature given its higher early complication rate.²

Periprosthetic femur fracture is a leading cause of early revision after primary THA.³ In fact, the literature demonstrates that there has been a rise in early and late intraoperative and postoperative periprosthetic femur fracture associated with the use of cementless implants.^4,5 Periprosthetic femur fracture requiring revision surgery is associated with a delayed recovery and an increased risk of deep periprosthetic joint infection, rerevision, and increased mortality.^6,7,8 Additionally, many elderly patients have persistent functional limitations with ambulation after revision hip surgery.⁸ Therefore, cemented femoral fixation remains the superior option in patients at increased risk of periprosthetic femur fracture after primary THA. Cemented femoral components provide value by reducing perioperative complications, improving functional recovery, and reducing pain in elderly patients and patients with poor bone quality undergoing THA.⁹ Cemented femoral fixation may hold even greater benefit in the DAA, where femoral complications including fracture, subsidence, and loosening have been reported to occur at a slightly higher rate compared with other hip approaches.

Cement functions primarily as a grout by moving into the voids of cancellous bone that have been washed free of fat and marrow to create an interlocked construct; this allows it to transfer load-bearing forces from the stem to the host bone. The practical phases to consider from a surgeon’s perspective are mixing, waiting, working, and setting times because throughout these phases the cement transforms from a liquid mixture into a solid material. The duration of each phase varies depending on ambient temperature, humidity, monomer and polymer temperature, mixing speed, ratio of polymer to monomer, and viscosity of the cement.¹⁰ The surgeon’s understanding of how these variables influence working time is vital to the safe handling and effective use of bone cement. An important variable to consider is that warmer, more humid operating room environments promote quicker cement setting time.¹⁰

The art or technique of cementing lies in the surgeon’s understanding of the optimal time to inject the cement in the femoral canal and when to insert the stem. The stem must be inserted at the desired height, alignment, and anteversion before the cement cures and held in the desired final position until the cement hardens. The goal is to achieve sustained pressurization of doughy cement into a dry bed of supportive cancellous bone that has been washed and dried from marrow contents and blood.¹¹ Working times and set times are variable based on cement viscosity (Figure 19.1).

Low-viscosity cement, with a relatively short working time, can result in early application as a wet cement, which may result in a poorer-quality cement mantle. Medium-viscosity cement provides more flexibility to the surgeon because it has a predictable transition between phases and its ability to be applied to bony surfaces and pressurized. High-viscosity cement can be difficult to extrude and pressurize through a cement gun. Additionally, any powder added from heat-stable antibiotics, when clinically indicated, can lengthen the cement working and setting time.¹² Ultimately, the surgeon’s understanding and comfort level with the handling properties should determine which cement to use. It is the recommendation of the authors that those adopting this technique consider using a medium-viscosity cement initially because it allows for a longer working time than low-viscosity cement, preventing it from being inserted too soon, while not becoming too viscous early on so that it becomes difficult to extrude through a cement gun.

Bone cement is a viscoelastic polymer that is affected by long-term properties of creep, stress relaxation, and fatigue. Bone cement functions well in compression and poorly in tension and shear.¹⁰ Fatigue failure originates in areas of high tensile stress and is reduced by stress relaxation during periods of relative unloading.¹⁰ Both the femoral component and cement must be effective conduits in transmitting the load to the host bone and withstand repetitive axial and rotational forces without loosening. For example, in a taper-slip stem design, the axial load on the stem is converted into radial compressive forces across the cement and transferred to the bone as hoop stress.¹³ This phenomenon helps preserve proximal bone stock over time by minimizing proximal femoral stress shielding.¹⁴

Cemented stem geometry, material, and surface finish all affect clinical survivorship. There are two main philosophies of cemented femoral stem fixation (Figure 19.2): taper-slip/force-closed fixation and composite beam/shape-closed fixation.^13,15 The taper-slip concept uses a dual- or triple-tapered stem with a smooth or highly polished surface finish allowing the stem to wedge into the cement mantle over the course of the first year, which improves proximal loading of the cement mantle. The composite beam concept relies on a strong bond between the stem and the cement, so the two different materials function as one unit during load transmission. Stems relying on the composite beam principle are roughened or matted to maximize the mechanical strength of the bond between the cement mantle and the stem. A collar may improve survivorship of composite beam fixation by improving proximal loading and resisting subsidence.

The risk of micromotion between the stem and cement mantle increases with repetitive axial and rotational forces over time; this phenomenon is well tolerated in polished tapered stems but can result in failure in matte finish stems.¹⁶ If the bond between the stem and cement breaks in a roughened/matted composite beam design stem, micromotion can occur, resulting in abrasive wear of the cement mantle and leading to osteolysis and aseptic loosening.¹⁷ For this reason, polished stems generally have better clinical survivorship than stems of the same geometry with a roughened/matted surface finish.¹⁶ Stem subsidence of 1 to 2 mm over the first year is commonly noted around the shoulder of collarless, polished, tapered stems and does not suggest loosening or impending failure of femoral reconstruction.¹⁵

The cemented stem cross-sectional shape influences the cement mantle thickness surrounding it and stress transfer.¹⁸ Rectangular and oval cross-sectional shapes are most commonly used in clinical practice. Although rectangular stems offer more rotational stability, the edges can create stress risers.¹⁵ Rounded edges are favored over sharp corners that occur at transition points, which are less likely to produce stress risers. Areas of increased stress concentration can lead to microfractures of the cement mantle, which can adversely affect the durability of the cement mantle.¹⁵

In summary, a variety of cemented stems exist with good long-term survivorship that use either a taper-slip or composite beam fixation method. Understanding the underlying principles behind stem design and function will help the surgeon appropriately select and use cemented implants to maximize the outcomes for patients.

The indications for cemented fixation for femoral components are broadening given the increasing age of our population. Advancing age, sex, proximal femoral bone morphology, history of metabolic bone disease or fragility fracture (especially osteoporosis), multiple coexisting medical comorbidities, inflammatory arthritis, and/or displaced femoral neck fracture (for hemiarthroplasty or THA) may all be considered for cemented femoral component use. Many surgeons use cementless femoral fixation for technical efficiency, which afforded 13 minutes of time savings in one study.¹⁹ This time savings should be weighed against potential complications in higher-fracture-risk patients.

Periprosthetic femur fracture is now consistently among the top three reasons for THA revision in multiple registries.² Abdel et al⁵ showed that both intraoperative and postoperative proximal femur fractures were greater with cementless femoral fixation, with intraoperative fracture being 14 times greater; postoperative fracture risk was found to be independent of age and sex. By careful selection of patients for cemented femoral fixation, outcomes are improved. This reliable and reproducible THA construct helps to mitigate complications, especially periprosthetic femur fracture.

The surgical technique that follows is broadly applicable to any polished tapered collarless cemented stem.²⁹ Cementing through the DAA is not significantly different from cementing through other approaches because technical considerations to achieve an excellent cement mantle remain the same. The only additional consideration for cementing through the DAA is that it may at times require one or more femoral releases to properly mobilize the femur and achieve straight access to the femoral canal for broaching and stem placement compared with a cementless stem. It is recommended that surgeons adopting the DAA technique for cemented stems give consideration to either a sawbones laboratory workshop or cadaver course to practice with the broaches and cement before implementing this technique in the operating room. This critical preparation will allow them to become familiar with the steps and handling of the cement as well as the proper DAA surgical exposure and instrumentation for femoral preparation. A summary of the steps is listed in Table 19.1.