The Influence of Spacer Design on the Rate of Complications in Two-Stage Revision Hip Arthroplasty

BackgroundAntibiotic cement spacers are used during 2-stage revision total hip arthroplasty for prosthetic joint infection. Complications including dislocation and periprosthetic fracture have been reported but a large cohort comparing spacer design features is lacking. We aimed to determine if spacer design is associated with perioperative complications.MethodsWe performed a retrospective review of antibiotic cement spacers implanted between 2004 and 2014. Radiographic assessment included leg length, offset, and bone loss (Paprosky classification). Clinical outcomes included dislocation, periprosthetic fracture, spacer fracture, infection cure, and overall reoperation rate. Univariate analysis, Student’s t-test, chi-squared test, or Kruskal-Wallis test was employed (P < .05).ResultsOne hundred eighty-five patients were treated: 42% were female and mean age was 64 years (range 24-93, standard deviation 13.6). Spacer types were (1) molded (53%), (2) antibiotic-coated prosthesis (30%), (3) handmade (12%); and (4) prefabricated (4%). Cemented acetabular liners were used in 3% (6/185). There was no loss to follow-up during the interstage period. Spacer complications occurred in 26% (48/185). Dislocation occurred in 9% (17/185) and was associated with reduced femoral offset of >5 mm (P = .033) and increased bone loss (P = .01). Spacer fracture occurred in 8% (14/185); 12% (12/97) molded versus 8% (2/23) handmade (P = .02). Periprosthetic femur fracture was associated with increased offset >5 mm (P = .01) and extended trochanteric osteotomy (P = .001).ConclusionDuring 2-stage total hip arthroplasty, antibiotic-loaded cement spacers had an overall complication rate of 26%. Spacer design, acetabular and femoral bone loss, and offset restoration were significantly associated with perioperative complications. We recommend the optimization of antibiotic-loaded cement spacer placement to minimize potential complications by focusing on restoration of leg-length and offset, ensuring adequate femoral fixation and paying attention to selection of an appropriate head/neck ratio.     

术中自制抗生素骨水泥占位器在治疗髋关节置换术后感染的并发症研究

目的:研究术中自制抗生素骨水泥占位器在治疗髋关节置换术后感染的控制率及其并发症。方法 :对2006年1月至2016年7月解放军总医院骨关节科髋关节置换术后感染行占位器植入患者265例(266髋)进行回顾性研究,其中男143例(144髋),女122例(122髋)。占位器均利用自行设计的压模器术中制作,全部占位器均加入万古霉素,同时根据细菌药敏结果加入另外一种抗生素。记录是否行大粗隆延长截骨术(ETO)取出感染假体、占位器并发症(断裂和脱位)的发生率、Harris评分和感染的控制率。结果:占位器植入时患者的平均年龄(57.4±14.2)岁。39例(14.7%)行ETO取出感染假体。38例(14.3%)出现了占位器的并发症,其中28例(10.5%)出现了占位器断裂,10例(3.8%)出现了占位器脱位。平均随访时间(83.4±14.6)个月。Harris评分从术前的47.56±14.23上升到末次随访的86.43±12.84(P0.05)。256例(96.6%)植入占位器术后感染得到了有效控制。Ⅱ期翻修术后到末次随访,4例患者再次出现感染,并再次行Ⅱ期翻修,感染得到控制。感染总的控制率为95.1%(252/265)。结论:术中自制抗生素骨水泥占位器控制髋关节置换术后感染具有显著效果,占位器并发症发生率较低,占位器结合钢丝、钛缆、捆绑带、异体骨板及螺钉不影响感染的控制。     

Two-Stage Revision Total Hip Arthroplasty With a Specific Articulating Antibiotic Spacer Design: Reliable Periprosthetic Joint Infection Eradication and Functional Improvement

Background

Two-stage revision utilizing spacers loaded with high-dose antibiotic cement prior to reimplantation remains the gold standard for treatment of periprosthetic joint infections (PJI) in total hip arthroplasty (THA) in North America, but there is a paucity of data on mid-term outcomes. We sought to analyze the survivorship free of infection, clinical outcomes, and complications of a specific articulating spacer utilized during 2-stage revision.

Total Hip Arthroplasty in Patients With Osteopetrosis

BackgroundOsteopetrosis is an inherited bone disease associated with high risk of osteoarthritis and fracture non-union, which can lead to total hip arthroplasty (THA). Bone quality and morphology are altered in these patients, and there are limited data on results of THA in these patients. The goals of this study were to describe implant survivorship, clinical outcomes, radiographic results, and complications in patients with osteopetrosis undergoing primary THA.MethodsWe identified 7 patients (9 hips) with osteopetrosis who underwent primary THA between 1970 and 2017 utilizing our total joint registry. The mean age at index THA was 48 years and included two males and five females. The mean follow-up was 8 years.ResultsThe 10-year survivorship free from any revision or implant removal was 89%, with 1 revision and 1 resection arthroplasty secondary to periprosthetic femoral fractures. The 10-year survivorship free from any reoperation was 42%, with 4 additional reoperations (2 ORIFs for periprosthetic femoral fractures, 1 sciatic nerve palsy lysis of adhesions, 1 hematoma evacuation). Harris hip scores significantly increased at 5 years (P = .04). Five hips had an intraoperative acetabular fracture, and 1 had an intraoperative femur fracture. All postoperative femoral fractures occurred in patients with intramedullary diameter less than 5 mm at a level 10 cm distal to the lesser trochanter.ConclusionPrimary THA in patients with osteopetrosis is associated with good 10-year implant survivorship (89%), but a very high reoperation (58%) and periprosthetic femoral fracture rate (44%). Femoral fractures appear associated with smaller intramedullary diameters.     

Total Femur Antibiotic Spacers: Effective Salvage for Complex Periprosthetic Joint Infections

BackgroundA simultaneous periprosthetic joint infection (PJI) of an ipsilateral hip and knee arthroplasty is a challenging complication of lower extremity reconstructive surgery. We evaluated the use of total femur antibiotic-impregnated polymethylmethacrylate (PMMA) bone cement spacers in the staged treatment of such limb-threatening PJIs.MethodsThirteen patients were treated with a total femur antibiotic spacer. The mean age at the time of spacer placement was 65 years. Nine patients had polymicrobial PJIs. All spacers incorporated vancomycin (3.0 g/40 g PMMA) and gentamicin (3.6 g/40 g PMMA), while 8 also included amphotericin (150 mg/40 g PMMA). Eleven spacers were biarticular. Twelve spacers were implanted through one longitudinal incision, while 8 of 12 reimplantations occurred through 2 smaller, separate hip and knee incisions. Mean follow-up after reimplantation was 3 years.ResultsTwelve (92%) patients underwent reimplantation of a total femur prosthesis at a mean of 26 weeks. One patient died of medical complications 41 days after spacer placement. At latest follow-up, 3 patients had experienced PJI recurrence managed with irrigation and debridement. One required acetabular component revision for instability. All 12 reimplanted patients retained the total femur prosthesis with no amputations. Eleven (91%) were ambulatory, and 7 (58%) remained on suppressive antibiotics.ConclusionTotal femur antibiotic spacers are a viable, but technically demanding, limb-salvage option for complex PJIs involving the ipsilateral hip and knee. In the largest series to date, there were no amputations and 75% of reimplanted patients remained infection-free. Radical debridement, antimicrobial diversity, prolonged spacer retention, and limiting recurrent soft tissue violation are potential tenets of success.Level of EvidenceIV.     

Impact of Hip Antibiotic Spacer Dislocation on Final Implant Position and Outcomes

BackgroundDislocation of dynamic antibiotic hip spacers during the treatment of periprosthetic joint infection is a well-described complication. Unfortunately, the repercussions of such events after reimplantation of the definitive prosthesis remain largely unknown. As such, we devised a study comparing the perioperative and postoperative outcomes of patients having undergone reimplantation with and without spacer dislocation.MethodsA search of our institutional database was performed. Two retrospective cohorts were created: dislocated and nondislocated hip spacers. The radiographic and clinical outcomes for each cohort were collected.ResultsThe two retrospective cohorts contained 24 patients for the dislocated group and 66 for the nondislocated group. Continuous variables noted to be significantly different between the dislocated and nondislocated groups were as follows: clinical leg-length discrepancy (1.35 cm vs 0.41 cm, P = .027), acetabular center of rotation (1.34 cm vs 0.60 cm, P = .011), total packed red blood cell transfusions (4.05 vs 2.37, P = .019), operative time (177.4 min vs 147.3 min, P = .002), and hospital length of stay (7.79 days vs 5.89 days, P = .018). Categorical variables noted to be significantly different were requirement for complex acetabular reconstruction (58.3% vs 13.7%, P < .001), requirement of constrained liners (62.5% vs 37.3%, P = .040), and dislocation after second stage (20.8% vs 6.1%, P = .039).ConclusionDislocation of dynamic hip spacers leads to inferior clinical results and perioperative outcomes after reimplantation of the definitive prosthesis. Additionally, complex acetabular reconstruction is often required. As such, every effort should be made to prevent hip spacer dislocation.     

Posterior-Stabilized Antibiotic Cement Articulating Spacer With Endoskeleton-Reinforced Cam Reduces Rate of Post-Cam Mechanical Complications in Prosthetic Knee Infection: A Preliminary Study

BackgroundPosterior-stabilized antibiotic cement articulating spacers (PS spacers) reduce spacer mechanical complications in prosthetic knee infections (PKIs); however, joint dislocation after femoral cam fracture has been reported. We hypothesized that the rate of post-cam mechanical complications is lower in PS spacers with an endoskeleton-reinforced cam.MethodA retrospective study of PKIs using PS spacers with or without a Kirschner wire–reinforced cam (K-PS or nK-PS spacers, respectively) was conducted between 2015 and 2019. The rates of post-cam mechanical complications and reoperation, as well as risk factors for post or cam failure, were analyzed.ResultsThe cohort included 118 nK-PS and 49 K-PS spacers. All patients were followed up for 2 years. The rate of joint subluxation/dislocation after femoral cam fracture was lower in K-PS (0%) than in nK-PS spacers (17.8%; P = .002). The reoperation rate for spacer mechanical complications was lower in K-PS (0%) than in nK-PS spacers (11.9%; P = .008). The identified risk factors for femoral cam fractures were body mass index ≥25 kg/m², femoral spacer size ≤2, and surgical volume ≤12 resection arthroplasties per year.ConclusionThis preliminary study highlights that K-PS spacers have a lower rate of post-cam mechanical complications than nK-PS spacers. We recommend the use of PS spacers with endoskeleton-reinforced cam when treating PKIs performed by surgeons with lower surgical volumes, especially in patients with higher body mass index and smaller femoral spacer sizes.     

Outcomes and Risk Factors of Extended Trochanteric Osteotomy in Aseptic Revision Total Hip Arthroplasty: A Systematic Review

BackgroundAlthough extended trochanteric osteotomy (ETO) is an effective technique for femoral stem removal and for the concomitant management of proximal femoral deformities, complications including persistent pain, trochanteric nonunion, and painful hardware can occur.MethodsThe US National Library of Medicine (PubMed/MEDLINE) and the Cochrane Database of Systematic Reviews were queried for publications utilizing the following keywords: “extended” AND “trochanteric” AND “osteotomy.”ResultsNineteen articles were included in the present study with 1478 ETOs. The mean overall union rate of the ETO was 93.1% (1377 of 1478 cases), while the overall rate of radiographic femoral stem subsidence >5 mm was 7.1% (25 of 350 cases). ETO union rates and femoral stem subsidence rates were similar between patients with periprosthetic fractures treated with total hip arthroplasty (THA) revision and ETO and patients treated with THA revision and ETO for reasons other than fractures. There was limited evidence that prior femoral cementation and older age might negatively influence ETO union rates.ConclusionThere was moderate quality evidence to show that the use of ETO in aseptic patients undergoing single-stage revision THA is safe and effective, with a 7% rate of ETO nonunion and subsidence >5 mm in 7%. ETO can be safely used in cases with periprosthetic fractures in which stem fixation is jeopardized and a reimplantation is required. A well-conducted ETO should be preferred in selective THA revision cases to prevent intraoperative femoral fractures which are associated with deteriorated clinical outcomes. The use of trochanteric plate with cables should be considered as the first choice for ETO fixation.     

Two-stage revision surgery to treat an infected hip implant. A comparison between a custom-made spacer and a pre-formed one

A retrospective study was conducted to evaluate the results of two-stage surgical treatment for infected hip implant using two different spacers in antibiotic-impregnated cement, one custom-made and one pre-formed. Out of a total of 20 patients treated between 1995 and 2003, the temporary implant of one custom-made spacer was carried out in 8 cases, while in the remaining 12 cases we resorted to using a pre-formed spacer (Spacer G). In both groups we observed one recurrence of infection, for an overall 90% success rate in terms of eradication of the infection. Custom-made spacers had a greater incidence of local complications (1 breakage, 1 dislocation, 1 sinking of the revision stem) as compared to pre-formed ones (1 dislocation). The clinical results evaluated using the Harris Hip Score showed a statistically significant difference (p < 0.05) in both groups as compared to the preoperative score. The use of a pre-formed spacer, although more costly as compared to that custom-made one, was advantageous in some ways, for example in terms of standardization of the implant method, the lower incidence of mechanical complications and the better functional results.     

Outcomes and Risk Factors Associated With 2-Stage Reimplantation Requiring an Interim Spacer Exchange for Periprosthetic Joint Infection

BackgroundPatients undergoing a 2-stage revision for periprosthetic joint infection (PJI) often require a repeat spacer in the interim due to persistent infection. This study aims to report outcomes for patients with repeat spacer exchange and to identify risk factors associated with interim spacer exchange in 2-stage revision arthroplasty.MethodsA total of 256 consecutive 2-stage revisions for chronic infection of total hip arthroplasty and total knee arthroplasty with reimplantation and minimum 2-year follow-up were investigated. An interim spacer exchange was performed in 49 patients (exchange cohort), and these patients were propensity score matched to 196 patients (nonexchange cohort). Multivariate analysis was performed to analyze risk factors for failure of interim spacer exchange.ResultsPatients in the propensity score–matched exchange cohort demonstrated a significantly increased reinfection risk compared to patients without interim spacer exchange (24% vs 15%, P = .03). Patients in the propensity score–matched exchange cohort showed significantly lower postoperative scores for 3 patient-reported outcome measures (PROMs): hip disability and osteoarthritis outcome score physical function (46.0 vs 54.9, P = .01); knee disability and osteoarthritis outcome score physical function (43.1 vs 51.7, P < .01); and patient-reported outcomes measurement information system physical function short form (41.6 vs 47.0, P = .03). Multivariate analysis demonstrated Charles Comorbidity Index (odds ratio, 1.56; P = .01) and the presence of Enterococcus species (odds ratio, 1.43; P = .03) as independent risk factors associated with 2-stage reimplantation requiring an interim spacer exchange for periprosthetic joint infection.ConclusionThis study demonstrates that patients with spacer exchange had a significantly higher risk of reinfection at 2 years of follow-up. Additionally, patients with spacer exchange demonstrated lower postoperative PROM scores and diminished improvement in multiple PROM scores after reimplantation, indicating that an interim spacer exchange in 2-stage revision is associated with worse patient outcomes.     

Vancomycin-Gentamicin Prefabricated Spacers in 2-Stage Revision Arthroplasty for Chronic Hip and Knee Periprosthetic Joint Infection: Insights Into Reimplantation Microbiology and Outcomes

BackgroundSecond-stage positive cultures in 2-stage revision arthroplasty are a matter of concern, as their influence in outcomes is not clearly defined. We sought to study reimplantation microbiology when using vancomycin-gentamicin prefabricated cement spacers in hip and knee periprosthetic joint infection. The associations of second-stage positive cultures with treatment failures and patient-associated factors were analyzed.MethodsWe conducted a retrospective cohort study, examining patients managed with 2-stage revision arthroplasty due to knee or hip chronic periprosthetic joint infection between 2010 and 2017. Prefabricated vancomycin-gentamicin cement spacers were used during the spacer stage. Intraoperative microbiological culture results after the first and second stages were evaluated. The primary end point was infection eradication or relapse.ResultsA total of 108 cases were included (61 hips and 47 knees). And 22.2% of patients had ≥1 second-stage positive culture, while 9.3% had ≥2 positive samples. Overall success, at an average follow-up of 46.4 months, was 77.8%. Treatment failure was higher among cases with positive cultures (15.5% vs 45.8%, P < .01) regardless of the number of positive samples. Diabetes was identified as a risk factor for second-stage positive cultures (P = .03); use of cement loaded with extra antibiotics for spacer fixation showed a protective effect (P < .01).ConclusionSecond-stage positive cultures were related to a higher failure rate when using vancomycin-gentamicin cement spacers. Diabetes increased the likelihood of second-stage positive cultures. The use of extra-antibiotic-loaded cement for spacer fixation during the first stage showed a protective effect.     

Explantation,Followed by Serial Debridement Without Antibiotic Spacers and Subsequent Revision With Cementless Components,Is Associated With High Remission Rates and Low Mortality in Periprosthetic Hip Joint Infections

BackgroundIn difficult-to-treat cases, it is necessary to add debridement steps in prosthesis-free interval of 2-stage exchange. We aimed to analyze the functional and clinical outcome of patients treated with a multistage exchange of total hip arthroplasty without the use of spacers, rather only cementless implants.MethodsBetween 2009 and 2018, 84 patients (mean age: 67.3 [39-90] years) suffering chronic late-onset periprosthetic joint infection (PJI) were treated using a multistage prosthesis exchange without spacers. The mean follow-up was 70 ± 45.3 [14-210] months. The treatment included prosthesis exchange and at least 1 additional revision step before a reimplantation, owing to ongoing acute infection in the prosthesis-free interval. High-efficiency antimicrobial therapy was administered in between, which was discontinued after cementless revision implantation.ResultsThe mean number of revisions between explantation and implantation was 2.6 (1-9). The most common microorganism was Staphylococcus epidermidis (53.6%) followed by Staphylococcus aureus (16.7%) and Cutibacterium acnes (11.9%). The bacterial load was more than one bacterium per patient in 38% of cases. All patients could be treated using a cementless implant. PJI remission was achieved in 92% of cases. Overall, 9 prostheses (11%) were replaced because of an ongoing PJI or fracture. The mean modified Harrison Hip Score was 63.4 (22-88) points. No patient died.ConclusionMultistage total hip arthroplasty exchange showed high remission rates and low mortality in difficult-to-treat cases. Spacer-free and multistage treatment had no negative effect on the success rate or functional outcome, consistent with the results of published 2-stage exchange studies. Implantation of an uncemented press-fit prosthesis was possible in all patients with no elevated periprosthetic fracture rate.     

Two-Stage Revision Total Hip Arthroplasty Without Spacer Placement: A Viable Option to Manage Infection in Patients With Severe Bone Loss or Abductor Deficiency

BackgroundHigh rates of spacer-related complications in two-stage exchange total hip arthroplasty (THA) have been reported. Patients with advanced bone defects and abductor deficiency may benefit from a nonspacer two-stage revision. This study reports on the clinical course of a contemporary two-stage exchange for periprosthetic hip infection without spacer insertion.MethodsWe reviewed 141 infected THAs with extensive bone loss or abductor damage who underwent two-stage exchange without spacer placement. The mean duration from resection arthroplasty to reimplantation was 9 weeks (2-29). Clinical outcomes included interim revision, reinfection, and aseptic revision rates. Restoration of leg-length and offset was assessed radiographically. Modified Harris hip scores were calculated. Mean follow-up was 5 years (3-7). Treatment success was defined using the modified Delphi consensus criteria.ResultsThirty-four patients (24%) had treatment failure, including 13 reinfections, 16 interim redebridements for persistent infection, 2 antibiotic suppressive therapies, and 3 prosthetic joint infection–related deaths. Aseptic rerevision after reimplantation was necessary in 14 patients (10%). Dislocation accounted for most aseptic complications, with 20 dislocations occurring in 15 patients (11%). Leg-length and offset were restored to preoperative measures. Mean modified Harris hip scores significantly improved from 35 points to 67 points.ConclusionA nonspacer two-stage exchange is a viable option for managing chronically infected THA with severe bone loss or abductor deficiency, showing comparable rates of interim revision and recurrence of infection. Cementless reimplantation demonstrates good midterm survivorship with comparable functional outcomes and leg-length restoration. However, dislocation continues to be a major concern.     

Articulating Knee Spacers in the Treatment of Periprosthetic Joint Infection: All Polyethylene Tibia or Tibial Insert?

BackgroundThe best antibiotic spacer for periprosthetic knee joint infection treatment is unknown. Using a metal-on-polyethylene (MoP) component provides a functional knee and may avoid a second surgery. Our study investigated complication rates, treatment efficacies, durabilities, and costs of MoP articulating spacer constructs using either an all-polyethylene tibia (APT) or a polyethylene insert (PI). We hypothesized that while the PI would cost less, the APT spacer would have lower complication rates and higher efficacies and durabilities.MethodsA retrospective review evaluated 126 consecutive articulating knee spacer (64 APTs and 62 PIs) cases from 2016 to 2020 was performed. Demographic information, spacer components, complication rates, infection recurrence, spacer longevity, and implant costs were analyzed. Complications were classified as follows: spacer-related; antibiotic-related; infection recurrence; or medical. Spacer longevity was measured for patients who underwent reimplantation and for those who had a retained spacer.ResultsThere were no significant differences in overall complications (P < .48), spacer-related complications (P = 1.0), infection recurrences (P = 1.0), antibiotic-related complications (P < .24), or medical complications (P < .41). Average time to reimplantation was 19.1 weeks (4.3 to 98.3 weeks) for APT spacers and 14.4 weeks (6.7 to 39.7 weeks) for PI spacers (P = .09). There were 31% (20 of 64) of APT spacers and 30% (19 of 62) of PI spacers that remained intact for an average duration of 26.2 (2.3 to 76.1) and 17.1 weeks (1.7 to 54.7) (P = .25), respectively, for patients who lived for the duration of the study. PI spacers cost less than APT ($1,474.19 versus $2,330.47, respectively; P < .0001).ConclusionAPT and PI tibial components have similar results regarding complication profiles and infection recurrence. Both may be durable if spacer retention is elected, with PI constructs being less expensive.     

Preformed gentamicin spacers in two-stage revision hip arthroplasty: functional results and complications

Two-stage revisions with antibiotic-loaded spacers have gained popularity for treating infected hip-joint arthroplasties. The aim of this prospective study was to assess patient functionality between stages and treatment impact on duration of hospital stay and to describe related complications. Sixty-one consecutive patients with infected hip arthroplasties underwent two-stage revision with preformed spacer implantation. Mean Harris Hip and Merle d’Aubigné scores between the two stages were 39.9 and 7.6, respectively. Forty-six patients (75.4%) were able to leave hospital between stages. Spacer dislocation occurred in 16.4%. No cases of spacer breakage were noted. Preformed cement spacers provide acceptable functional outcome between revision hip arthroplasty stages and facilitate the surgical procedure without increasing mechanical complication rates.     

Comparison of Functional and Radiographic Outcomes Between Two Fixation Methods for Extended Trochanteric Osteotomy in Revision Total Hip Arthroplasty: A Retrospective Cohort Study

BackgroundTo compare the functional and radiographic outcomes between two fixation methods for extended trochanteric osteotomy (ETO) in revision total hip arthroplasty (rTHA).MethodsIncluded in this study were 64 patients who underwent ETO in rTHA using either claw-plate fixation (claw-plate group, n = 31) or cable-alone fixation (cable group, n = 33) in our hospital from 2008 to 2020. The functional and radiographic results and complications were compared between the groups during a mean follow-up period of 64 and 78 months.ResultsThe Harris hip score and visual analogue scale at the last follow-up improved significantly in both groups, showing no significant statistical difference between the two fixation methods. In the cable group, the mean abductor lever arm, the proximal migration, and medial migration in the affected hip were significantly decreased compared to those in the contralateral normal hip (P < .05), whereas in the claw-plate group no significant statistical differences were observed between two sides. No or slight limping occurred in 25 patients (81%) in the claw-plate group and 16 patients (48%) in the cable group (P = .007). A multiple logistic regression demonstrated that claw-plate fixation could reduce the incidence of postoperative moderate-to-severe limping.ConclusionBoth claw-plate fixation and cable-alone fixation could improve the functional performance of rTHA with ETO, whereas claw-plate fixation could offer superior biomechanical results and gait improvement as compared with cable-alone fixation.     

The Use of Extended Trochanteric Osteotomy in 2-Stage Reconstruction of the Hip for Infection

BackgroundThe effect of extended trochanteric osteotomy (ETO) with immediate cerclage wire fixation on the scene of chronic periprosthetic joint infection on infection eradication and the osteotomy healing remains unclear.MethodsOne hundred seventeen patients who underwent two-stage revision total hip arthroplasty for chronic periprosthetic joint infection were enrolled in the study. The minimum follow-up was 2 years. Of these, 48 patients had underwent ETO and immediate cerclage wire fixation during the first-stage surgery, while 69 did not undergo ETO or any other osteotomy. In addition, 18 patients had underwent ETO in the second-stage reimplantation surgery. Repeated debridement, curative rate of infection, and complications were compared between the 2 groups. Meanwhile, osteotomy healing between the first and second osteotomy were also compared.ResultsThe repeated debridement rate and curative rate of infection were 2.1% and 95.8% in the ETO group, compared with 13.0% and 82.6% in the non-ETO group; there were significant difference between the 2 groups in these parameters (P = .037 and .030, respectively). Meanwhile, osteotomy healing rate was 93.8% in first-stage surgery with infection scene and 100% in second-stage surgery without infection; no significant difference was detected in osteotomy healing rate and time to healing (P = .278 and .803, respectively). The rate of complication was similar in both groups.ConclusionsETO combined with immediate cerclage wire fixation does not appear to reduce the rate of infection eradication. There was no harmful effect on complication rate and osteotomy healing.     

大转子延长截骨在全髋关节翻修术中应用的临床评价

目的 回顾性研究采用大转子延长截骨(extended troehanteric osteotomy,ETO)行全髋关节翻修术后股骨柄的位置变化,评价ETO在股骨假体稳定件髋关节翻修术中的作用.方法 1998年1月至2007年6月,采用ETO对股骨柄或骨水泥壳固定稳定性全髋关节33例33髋进行翻修.翻修术后采用Harris评分和MOMAC评分评估髋关节功能,摄动态X线片观察截骨块愈合、假体位置改变及股骨柄与股骨髓腔匹配等情况.结果 25例随访12～103个月,平均63个月.Harris评分由术前平均38.4分,提高到末次随访时88.7分;WOMAC评分由术前平均56.2分,降至末次随访时42.8分.大转子截骨块均在术后4～10个月骨性愈合.3例发生股骨柄下沉.平均3.4mm.股骨柄假体出现外翻、内翻各1例.无术中或术后骨折、钢丝断裂、感染、假体周围骨溶解以及异位骨化发生.术后关节脱位1例.结论 对假体固定稳定性股骨柄进行翻修,采用ETO有利于假体的安全取出,术后截骨块愈合率高,延长截骨不影响假体稳定性.股骨柄下沉、位置改变、截骨块骨折等并发症发生率低.     

Complications and Outcomes Associated With a Novel,Prefabricated, Articulating Spacer for Two-Stage Periprosthetic Joint Infection Treatment

BackgroundVarious prefabricated articulating spacer options have been described for 2-stage treatment of chronic periprosthetic joint infection, but their results are poorly generalizable between designs due to differing antibiotic and material properties. This study reports outcomes for a novel, prefabricated, commercially available cement-on-cement articulating spacer.MethodsA retrospective review of prospectively collected data for patients undergoing treatment with a prefabricated articulating cement spacer was performed. Outcomes were categorized as spacer complications, reimplantation rates, function, reinfection, and mortality.ResultsSeventy-six knees and 28 hips were analyzed. Spacer survival free of fracture, instability, or other implant-related complication until reimplantation was 100%. There were no bony or spacer fractures during the interstage or reimplantation. Reimplantation occurred in 84.6% of resected joints. Following spacer implantation, all but 1 patient was allowed to bear weight. The proportion of patients requiring an assistive device decreased from 67% prior to resection to 31% following reimplantation. Knee flexion improved from an average of 88.1° before resection to 111.9° following reimplantation. Eighty-seven percent of cases were infection free at mean follow-up of 16.6 ± 10.4 months.ConclusionStudy results demonstrate that this novel, prefabricated, articulating antibiotic spacer is safe, allows for good interstage function, and results in reasonable infection eradication rates at early term follow-up.Level of evidenceTherapeutic Level III.