Impact of introducing custom-made articulating spacers: A retrospective cohort study on two protocols for two-stage hip revision

Abstract

BACKGROUND

Two-stage revision is the most common treatment for chronic periprosthetic joint infection of the hip, involving a resection arthroplasty with or without placement of an antibiotic-loaded spacer, followed by antibiotic therapy before reimplantation.

AIM

To compare the outcomes and complications of two consecutive treatment protocols for two-stage revision arthroplasty of the infected hip: One using Girdlestone with an antibiotic holiday, the other using custom-made articulating spacers (CUMARS) without an antibiotic holiday.

METHODS

In this retrospective study, two consecutive cohorts were compared. Group A (2017-2020) underwent two-stage revision with a Girdlestone and an antibiotic holiday before reimplantation, while Group B (2020-2023) received CUMARS whenever possible, and no antibiotic holiday, or a Girdlestone if indicated. The primary outcome was successful infection eradication after one year. Secondary outcomes included surgical duration, length of hospital stay, weight-bearing allowance, discharge destination, and complications.

RESULTS

A total of 98 patients were included: 39 patients in Group A and 59 patients in Group B. Successful infection eradication after one year was achieved in 69% of Group A and 83% of Group B (P = 0.164). Patients in Group B were more frequently allowed to bear weight (64% vs 18%, P < 0.001), had a shorter in-hospital stay (9 vs 16 days, P < 0.001), and were more often discharged home after the first surgery (48% vs 24%, P = 0.048). No significant differences were found in (mechanical) complications.

CONCLUSION

A protocol including CUMARS is a safe and effective treatment, offering faster recovery, shorter length of hospital stay, and enabling more patients to return home during the interval. This reduces strain on patients and the healthcare system, potentially saving costs, without compromising infection control or increasing (mechanical) complications.

Key Words: Periprosthetic joint infection; Two-stage revision; Girdlestone; Custom-made articulating spacer; Spacer; Antibiotic holiday

Core Tip: This retrospective cohort study compares two consecutive treatment protocols for two-stage hip revision in periprosthetic joint infection: One using only Girdlestone and another incorporating custom-made articulating spacers (CUMARS) whenever possible, or a Girdlestone when necessary. While infection eradication rates were similar, the introduction of CUMARS was associated with shorter hospital stays, earlier mobilization, and more frequent discharge to home. These results suggest that CUMARS facilitates a faster recovery for suitable patients and reduce healthcare burden without compromising infection control, making them a valuable addition to the treatment algorithm. For patients with contraindications, a Girdlestone remains a viable option.

INTRODUCTION

Two-stage revision arthroplasty is the most common treatment for chronic periprosthetic joint infection (PJI) of the hip, consisting of two surgeries and antibiotic therapy of 6 to 12 weeks. Traditionally, a Girdlestone resection arthroplasty was performed, frequently with an antibiotic holiday before reimplantation. The absence of a functional hip joint severely immobilized patients, prolonging hospital stays and often requiring admission to an extended care facility[1-3].

Over the years, treatment protocols have changed: Antibiotic holidays are no longer mandatory, intervals can be long or short, and antibiotic-loaded interval spacers are advocated[4-6]. More recently, the use of functional/custom-made articulating spacers (CUMARS) has increased. First described by Tsung et al[7], CUMARS utilize standard commercially available hip implants coated in antibiotic-loaded cement tailored to the causative pathogen. CUMARS maintain soft tissue tension, preventing fibrosis and retraction, which facilitates easier reimplantation and reduces leg length discrepancy and dislocation risk after reimplantation[1-3,8]. CUMARS improve functional outcomes while maintaining locally sufficient antibiotic levels until the second-stage surgery[3,9-11]. However, spacers introduce the risk of mechanical complications, including spacer dislocation, (peri)-spacer fracture, and acetabular bone loss[11,12]. These complications are particularly associated with prefabricated/molded spacers and spacers without an acetabular component. They are less frequently or not reported in CUMARS, which also have the advantage of allowing (partial) weight-bearing, potentially shortening hospital stays and enabling patients to return home between stages[13-18].

Traditionally, following the first-stage surgery and subsequent antibiotic treatment, a period without antibiotics, known as the antibiotic holiday, was recommended. The rationale behind this approach was to determine whether it was safe to proceed with second-stage surgery, as any residual infection would have the opportunity to reemerge during this drug-free interval[6]. Secondarily, if tissue cultures remained negative after the second stage procedure, antibiotics could be ceased. However, this approach has proven to be challenging, as there are currently no reliable preoperative tests to definitively exclude any persistent infection prior to reimplantation[6,19,20]. Consequently, the antibiotic holiday is now frequently discouraged, with continuous antibiotic treatment being advocated instead[20,21]. Nevertheless, robust evidence remains limited, as available studies are scarce and present conflicting results[19,22,23]. The International Consensus Meeting on infection also acknowledged the lack of conclusive evidence and, consequently, was unable to issue a formal recommendation on the need for and/or the ideal length of an antibiotic holiday[24].

Motivated by the significant impact of a Girdlestone on a patient's mobility and health, and a strive to limit in-hospital length of stay, we introduced a new protocol including CUMARS and no antibiotic holiday in our center in 2020[25]. We hypothesize that the introduction of the new protocol leads to faster recovery, fewer postoperative complications, and easier reimplantation compared to a Girdlestone interval with an antibiotic holiday for two-stage revision of the infected hip, while maintaining the same infection eradication rate.

MATERIALS AND METHODS

A retrospective single-center cohort study was conducted at a tertiary referral center for PJI in the Netherlands. All patient records of individuals who underwent a two-stage revision arthroplasty of the hip for infection, as determined by a multidisciplinary team based on the EBJIS criteria for PJI, between 2017 and 2023 were reviewed for inclusion in the study. Patients with a two-stage hip arthroplasty for infection were included in the study. Exclusion criteria included one-stage revisions, intentional definitive Girdlestone procedures, and cases in which the first or second-stage surgery was performed at other institutions.

This study involves two consecutive cohorts. In the first cohort, from 2017 to 2020, only Girdlestone (Figure 1) intervals were used (Group A). At the beginning of this period, gentamicin beads were left in place during the first-stage surgery and were removed 2 weeks later. Patients were instructed to avoid weight-bearing during the interim period to limit leg length discrepancy. Antibiotic treatment was discontinued for at least two weeks before the second-stage procedure. After reimplantation, patients received intravenous antibiotics for five days, which were discontinued if cultures remained negative on day five. If cultures were positive, patients received an additional course of targeted antibiotic therapy for at least six weeks.

Figure 1 Anteroposterior radiograph of the right hip of a patient in group B, with a custom-made articulating spacers.

In the second cohort, from 2020 to 2023, a new protocol was introduced in our center (Group B). After the resection arthroplasty, a CUMARS (Figure 2) was created by coating commonly used femoral and acetabular components (Link^® Lubinus Classic Plus Stem and Link^® IP Acetabular Cup (Waldemar Link GmbH & Co. KG, Hamburg, Germany)) with antibiotic-loaded cement (Palacos^® R+G bone cement, Heraeus Medical GmbH, Wehrheim, Germany), with additional antibiotics (1 g per batch of cement) tailored to the patient's specific pathogen (Figure 3). The spacer was then loosely implanted when the cement had a doughy consistency, ensuring easy removal during the second-stage surgery. Rotational stability of the CUMARS is achieved by folding the cement around the edges of the proximal femur and acetabulum. Patients were permitted partial weight-bearing (up to 50% of bodyweight) during the interval based on a recommendation by the operating surgeon. Patients were continuously treated with a minimum of 6 weeks of antibiotics following the first-stage surgery, including 2 weeks intravenously, up until reimplantation. After reimplantation, they received an additional 6-week course of antibiotics, with 1 week administered intravenously, totaling a minimum antibiotic duration of 12 weeks in total. In Group B, a Girdlestone interval was used in case a CUMARS was deemed contraindicated by the treating orthopedic surgeon intraoperatively based on bone stock and fracture risk. These patients received antibiotic treatment according to the protocol used in Group A.

Figure 2 Anteroposterior radiograph of the right hip of a patient in group B after a Girdlestone resection arthroplasty. A spacer was deemed contraindicated due to a 22 cm long extended trochanteric osteotomy, necessary for cement removal.

Figure 3 Construction of a custom-made articulating spacers. A Lubinus Classic stem and a polyethylene IP cup are coated with Palacos R+G bone cement with added extra antibiotics, leaving the posterior surface of the cup and the tip of the stem uncoated to facilitate easier removal.

All patients in both groups received preoperative antibiotic prophylaxis. The surgeries were performed through a posterolateral approach by three senior orthopedic surgeons. During the first-stage surgery, the infected prosthesis, any osteosynthesis material if present, and/or the native femoral head were removed. An extended trochanteric osteotomy (ETO) was performed to remove all cement if necessary. All prostheses were sent for sonication, and at least five cultures were obtained. Postoperatively, after both the first and second-stage surgery, patients were discharged home or to an extended care facility, depending on their mobility and care needs. If necessary, patients could receive intravenous antibiotic treatment both at home and in the extended care facility. The second-stage surgery was generally performed after 6-8 weeks.

General patient characteristics, surgical and treatment details, complications, and infection status were collected from the patient records (Table 1). The primary outcome was successful infection eradication, defined as the absence of clinical suspicion of infection, no requirement for an additional (two-stage) revision due to infection, and no PJI-related death at one year postoperative. Secondary outcomes included surgical time, blood loss, length of hospital stay, postoperative weightbearing allowance, complications, and discharge destination.

Table 1 General patient characteristics, n (%).

Variable	Group A (n = 39)	Group B (n = 59)	P value
Age, mean (SD)	66 (11.5)	64 (14.6)	0.41
Gender male	25 (64)	28 (47)	0.15
BMI, mean (SD)	28 (5.4)	29 (6.3)	0.32
Diabetes	4 (10)	9 (15)	0.56
ASA score			0.53
1	0 (0)	2 (3)
2	22 (56)	34 (58)
3	17 (44)	22 (37)
4	0 (0)	1 (2)
Infected material			0.45
Primary prosthesis	22 (58)	27 (49)
Revision prosthesis	12 (32)	17 (30)
Internal fixation	4 (11)	7 (13)
Septic arthritis	0 (0)	4 (7)
Post-traumatic indication	10 (56)	15 (42)	0.39
Infection duration, days (SD)	468 (498.3)	411 (407.9)	0.57
Earlier infection related surgery	19 (49)	26 (48)	1.00
Earlier two-stage revision	4 (11)	7 (14)	0.75
Mean months of follow-up (SD)	32 (22.0)	19 (10.3)	< 0.001

BMI: Body mass index; ASA: American Society of Anesthesiologists score.

Descriptive statistics are reported as number (percentage) or mean (SD), as appropriate. The student’s t-test was used to compare numerical variables, while Fisher's exact or χ² test was applied for categorical variables. Statistical significance was set at P < 0.05. Statistical analysis was performed using IBM SPSS Statistics (version 28.0.1.0).

RESULTS

From 2017 to 2023, a total of 98 patients underwent a two-stage revision of the hip: 39 patients in Group A received a Girdlestone, while 35 and 24 patients in Group B received a CUMARS or a Girdlestone, respectively. The groups were comparable at baseline in terms of general patient and infection characteristics (Table 1). The mean age was 65 years (SD 13.4), 54% were male, and the mean follow-up duration was 24 months (SD 16.9). The distribution of the causative pathogens is detailed in Table 2.

Table 2 Distribution of causative pathogens, n (%).

Pathogen	Group A (n = 39)	Group B (n = 59)
Polymicrobial	8 (21)	7 (12)
S. Aureus	9 (23)	12 (20)
S. epidermidis	4 (10)	11 (19)
Other CoNS	5 (13)	9 (15)
Cutibacterium acnes	0 (0)	5 (6)
Streptococci	5 (13)	3 (5)
E. Coli	1 (3)	3 (5)
Enterococci	3 (8)	2 (3)
P. Aeruginosa	1 (3)	1 (2)
Other	2 (5)	1 (2)
Culture negative	1 (3)	5 (9)

CoNS: Coagulase negative staphylococci.

Successful infection eradication at one year of follow-up was achieved in 69% and 84% of patients in Group A and Group B, respectively (P = 0.16). In Group A, there were six (21%) cases of persistent infection and three (10%) cases of reinfection with a different pathogen. In Group B, four (8%) cases of persistent infection and four (8%) cases of reinfection caused by a different pathogen.

Treatment details per group are provided in Table 3. The mean operative time for the first stage was significantly shorter in Group A. The mean operative time for the second-stage procedure was comparable between the groups. Patients in Group B were permitted significantly greater weight-bearing during the interim period, had a shorter duration of hospital stay, and were more frequently discharged home following the first-stage surgery. These differences were no longer observed following the second-stage surgery.

Table 3 Treatment details, n (%).

Variables	Group A	Group B	P value
First-stage surgery	n = 39	n = 59
ETO	12 (35)	19 (41)	0.38
Gentamicin beads	6 (15)	0 (0)	0.07
Mean surgical time, min (SD)	149 (49.4)	179 (60.0)	0.02
Mean blood loss, mL (SD)	1128 (581.6)	984 (531.5)	0.32
Interval weightbearing allowance1			< 0.001
0%	32 (82)	21 (36)
10%	7 (18)	29 (49)
50%	0 (0)	9 (15)
Mean length of hospital stay, days (SD)	16 (8.3)	9 (6.5)	< 0.001
Discharge destination			0.048
Home	9 (26)	28 (48)
Extended care facility	26 (74)	30 (52)
Second-stage surgery	n = 35	n = 58
Mean interval duration, days (SD)	213 (266.3)	110 (113.9)	0.01
Mean surgical time, min (SD)	157 (40.1)	165 (54.7)	0.51
Mean blood loss, mL (SD)	1042 (710.1)	886 (586.0)	0.36
Postoperative weightbearing allowance1			0.71
0%	0 (0)	2 (4)
10%	3 (9)	5 (9)
50%	14 (40)	23 (41)
100	18 (51)	26 (46)
Mean length of hospital stay, days (SD)	10 (10.9)	8 (5.6)	0.16
Discharge destination			0.83
Home	20 (61)	31 (57)
Extended care facility	13 (39)	23 (43)

¹Percentage of bodyweight as advised by treating surgeon.

ETO: Extended trochanteric osteotomy.

In Group A, reimplantation was not performed in four patients, compared to one patient in Group B (P = 0.08). In Group A, two patients declined further surgery and two had died of PJI-related causes during the interval. The patient in Group B, who received a Girdlestone, was deemed medically unfit for reimplantation and was subsequently treated with suppressive antibiotic therapy.

Complications are listed in Table 4. No significant differences were observed between the groups for any complication, except for total PJI-related mortality. In Group A, five patients died, whereas no deaths occurred in Group B (P = 0.01). Two patients died during the interval, and three patients died after reimplantation. Three patients died from sepsis, one from complications of intraoperative bleeding, and one from hospital-acquired pneumonia. A total of 55 reoperations were performed in 28 patients, with no significant differences observed between the groups (Table 5).

Table 4 Complications, n (%).

Variables	Group A	Group B	P value
During interval	n = 39	n = 59
Any complication	20 (51)	31 (53)	1.00
Anemia	13 (33)	21 (36)	1.00
AKI	4 (10)	4 (7)	0.71
Delirium	3 (8)	1 (2)	0.30
Decubitus	1 (3)	3 (5)	1.00
Pneumonia	1 (3)	0 (0)	0.40
PJI related death	2 (5)	0 (0)	0.16
Cup loosening	0 (0)	1 (2)	1.00
Spacer dislocation	0 (0)	1 (2)	1.00
After second-stage surgery1	n = 35	n = 58
Any complication	17 (49)	34 (59)	0.39
Anemia	9 (26)	17 (29)	0.81
AKI	1 (3)	5 (9)	0.40
Delirium	1 (3)	1 (2)	1.00
Decubitus	0 (0)	0 (0)
Pneumonia	1 (3)	1 (2)	1.00
PJI related death	3 (9)	0 (0)	0.05
Dislocation	3 (8)	6 (10)	1.00
Mean dislocations per patient (SD)	3.0 (1.0)	2.6 (1.6)	0.67
Aseptic loosening	0 (0)	2 (3)	0.53

¹Until the end of follow-up.

AKI: Acute kidney injury; PJI: Prosthetic joint infection.

Table 5 Reoperations, n (%).

Variable	Group A (n = 39)	Group B (n = 59)	P value
Any reoperation	8 (21)	20 (34)	0.27
Mean surgeries per patient (SD)	2.25 (1.5)	1.85 (1.2)	0.47
During interval
Removal of spacer due to infection	0 (0)	1 (2)	1.00
Debridement	1 (3)	0 (0)	0.40
After second-stage surgery
DAIR	5 (14)	16 (27)	0.20
Two-stage revision	4 (11)	5 (9)	0.72
Revision (non-infectious reasons)	2 (6)	3 (5)	1.00
Plate fixation	1 (3)	1 (2)	1.00

DAIR: Debridement, antibiotics, and implant retention.

Sub-analysis of Group B: Girdlestone vs CUMARS

When dividing Group B based on the type of treatment received, patients with a Girdlestone were significantly younger [mean age 59 (SD 14.2) vs 67 (SD 14.2) years, P = 0.049]. No other significant differences were observed at baseline. Infection eradication rates at one year were 86% for CUMARS and 82% for Girdlestones (P = 1.00). CUMARS patients had three persistent infections and one reinfection with a new pathogen, while Girdlestone patients had one and three, respectively. Patients with a CUMARS had a significantly shorter second-stage operative time, with a mean duration of 143 (SD 64.5) minutes compared to 196 (SD 33.6) for those treated with a Girdlestone (P < 0.001). Patients with CUMARS were more frequently discharged home: 59% vs 33% after the first-stage surgery (P = 0.07) and 65% vs 45% after the second-stage surgery (P = 0.25) for CUMARS and Girdlestones, respectively.

No statistically significant differences in complications were observed. Following the first-stage surgery, 18 (51%) patients with CUMARS and 13 (54%) patients with a Girdlestone experienced any complication (P = 1.00). After the second-stage surgery, this was the case for 17 (49%) and 17 (74%) patients with CUMARS and Girdlestone, respectively (P = 0.06). Anemia occurred in 20% of CUMARS and 43% of Girdlestone patients following the second-stage surgery (P = 0.08). Dislocations after reimplantation occurred in two (6%) patients with CUMARS and five (22%) patients with a Girdlestone (P = 0.10). Nine (26%) patients with CUMARS needed additional surgery after reimplantation compared to 11 (46%) Girdlestone patients (P = 0.16).

DISCUSSION

This study aimed to evaluate two treatment protocols for two-stage revision arthroplasty of the hip by comparing two consecutive patient cohorts: The first received a Girdlestone interval with an antibiotic holiday, while the second cohort was treated with a CUMARS and no antibiotic holiday. Successful eradication of infection after one year was not statistically significantly different between the groups [69% and 84% of patients in groups A and B, respectively (P = 0.16)]. Interpretation of these results is complicated, as it is difficult to determine which portion of the outcomes can be attributed to the use of CUMARS, the application of antibiotic-loaded cement, or the presence or absence of an antibiotic holiday. Direct comparison of these results with other studies is challenging due to heterogeneity in study designs, treatment protocols, spacer types, and the limited availability of comparable studies. Nevertheless, similar to the findings of the present study, most studies report a trend toward a higher infection eradication rate associated with the use of spacers, without reaching statistical significance[3,11]. With reported infection eradication rates ranging from 67% to 97%, our results are in concordance with current literature[2,3,11,26]. A study by Cabrita et al[1] is the only study to date to report a statistically significant difference, demonstrating fewer reinfections with the use of spacers. This could be caused by the absence of local antibiotics or the hematoma-filled dead space resulting from prosthesis removal, which is more susceptible to infection.

By introduction of the new protocol in Group B, the mean length of hospital stay was nearly halved, patients were allowed to bear more weight, and more patients were discharged home following the first-stage surgery. These findings are consistent with other literature and can probably mostly be attributed to the CUMARS[1-3]. Contrary to the study by Cabrita et al[1], in our findings these differences were no longer present after the second-stage surgery. This protocol reduces the overall burden on patients due to the improved mobility and a quicker return home during the interval period. Although treatment costs were not analyzed in this study, the shorter hospital stay and reduced need for extended care facility admission suggest that overall costs are likely to be lower in Group B.

Unfortunately, aside from the orthopedic surgeon’s weight-bearing recommendation, functional outcomes could not be assessed in this study due to a lack of available data. However, comparable studies report superior Harris Hip Score following two-stage revisions with an interval spacer compared to a Girdlestone[3,11]. Additionally, improved interim function has been described with the use of CUMARS compared to molded spacers[13,14]. We believe the shorter hospital stay and increased ability for our patients with a CUMARS to return home during the interval, are an expression of improved mobility compared to the Girdlestone patients.

Logically, the duration of surgery for the first-stage procedure was longer in group B than in group A, which is caused by the time it takes to fabricate and implant the CUMARS. No difference in surgical time was observed during the second-stage surgery when comparing the two consecutive cohorts. However, a significant difference was present when comparing second-stage surgery times of patients with Girdlestones to those with CUMARS, in favor of the latter. This finding aligns with existing literature and is likely due to the preservation of tissue tension and joint movement by the spacer during the interim period, making surgical planes and bony landmarks easier to identify, and allowing for simpler reimplantation procedure[1-3,11].

We expected to observe more complications such as delirium, decubitus, and pneumonia in Group A due to reduced mobility; however, this was not the case. No significant differences were found between the groups regarding any individual complication or the total number of complications, except for PJI-related mortality. Most existing literature similarly reports no significant differences in complications, except for dislocations after reimplantation, which contrasts with our findings[2,3,11]. This discrepancy may be explained by our comparison of two consecutive cohorts. Within Group B, when comparing Girdlestone with CUMARS, there was no significant difference in the number of dislocations (P = 0.10), however this may be caused by the limited number of patients to compare within this group. There were significantly more deaths in Group A compared to Group B (5 vs 0, P = 0.01). This suggests that a protocol involving CUMARS and continuous antibiotic therapy may be associated with improved survival. Cabrita et al[1] is the only comparable study reporting on PJI-related mortality and also observed fewer deaths with the use of spacers, although this did not reach statistical significance. Larger studies are therefore necessary to confirm these findings.

There were two mechanical complications among 35 patients with a CUMARS related to spacer use (6%): One dislocation and one loosening of the cup. Peri-spacer fracture was not observed. This complication rate is considerably lower than the reported average of 16.3% for mechanical complications of hip spacers[12]. Jones et al[16] found that dislocation is associated with a reduced offset, whereas peri-spacer fractures are linked to an increased offset. Furthermore, they demonstrated that CUMARS are the most effective type of spacer for restoring offset compared to other spacer designs[16]. CUMARS offer the same range of options as standard total hip prostheses, whereas molded or prefabricated spacers are only available in a limited range of sizes. Additionally, acetabular complications such as pelvic protrusion were also absent in this study. Burastero et al[17] demonstrated that spacers without an acetabular component cause significantly more acetabular bone loss. Increased acetabular bone loss leads to a greater need for complex revision hardware[27].

This study has several limitations, including a relatively small sample size and its retrospective design, which is prone to missing data and may introduce selection, inclusion, and information biases. A small sample size can lead to a type II error, and results should therefore be interpreted with caution. We have made efforts to minimize the risk of selection and inclusion bias-a common issue in retrospective cohort studies, as not all patients are suitable candidates for spacers - by not selecting groups based on the type of treatment, but instead using two consecutive cohorts including all treated patients during the specific timeframe. However, some heterogeneity between the two groups was still present as the follow-up period for Group B was shorter. Immortal time bias was limited by choosing a determined endpoint of follow-up at one year for the primary outcome. However, this period is relatively short, a more detailed analysis could be conducted after five years of follow-up. Furthermore, as previously mentioned, the lack of available objective data on the functional outcomes of both groups means these results should be interpreted with caution.

To our knowledge, this is the first study to directly compare the outcomes of patients treated with consecutive treatment protocols for two-stage revision of the hip including the introduction of CUMARS. The results of our study confirm swifter recovery during the treatment interval when using CUMARS for two-stage revision arthroplasty of the infected hip.

Although it was not the objective of this study, CUMARS offers the advantage of potentially delaying or even avoiding reimplantation[13,28]. In this study, the longest spacer interval was 114 days, and no patient retained their spacer indefinitely. However, this can potentially be a significant benefit for elderly patients with multiple comorbidities and low functional demands. In a study by Wang et al[13], as many as 58% of patients opted to retain their spacer while maintaining a comparable infection eradication rate to the classic two-stage revision group.

CONCLUSION

A protocol including CUMARS and no antibiotic holiday is a safe and effective treatment option for suitable patients, as it enables faster recovery during the interval period, while maintaining an adequate infection eradication rate and without increasing mechanical complications. Additionally, CUMARS seem to reduce the strain on the healthcare system by shortening the average hospital stay for the entire cohort and enabling more patients to be discharged home, thereby potentially leading to significant cost savings. We believe a CUMARS should be the preferred type of interval spacer over a Girdlestone or other types of spacers in any patient treated with two-stage revision surgery for PJI of the hip. For patients with severe bone loss where a CUMARS is deemed contraindicated, a Girdlestone remains a viable option. The optimal revision strategy for infection eradication remains a subject for further investigation. Whether the indications for a CUMARS can be stretched in unfavorable situations (for instance in case of massive bone loss at the femoral and/or acetabular side, or in case of necessity of a long ETO for cement removal) and if frail patients could benefit from retaining a CUMARS should be further evaluated.