Citations

Aims Two-stage exchange arthroplasty with an antibiotic-eluting cement spacer remains the predominant strategy in the USA for managing chronic periprosthetic joint infection (PJI) following total hip arthroplasty (THA). The aim of this study was to evaluate a commercially available, partially intraoperatively fabricated articulating high-dose antibiotic cement spacer, focusing on survival, complications, and patient-reported outcomes. Methods A total of 298 patients (302 THAs) underwent two-stage exchange arthroplasty for PJI using a specific articulating antibiotic spacer between August 2005 and May 2022. Patients with a previous failed two-stage exchange were excluded, although 121 THAs (302, 40%) had undergone previous PJI-related procedures. The mean age of the patients was 65 years (SD 11), the mean BMI was 32 kg/m 2 (SD 7), and 116 (38%) were female. Most patients were classified as McPherson host B (158; 52%) and limb grade 2 (165; 55%), and 265 (88%) met the 2011 Musculoskeletal Infection Society criteria. The mean follow-up was six years (2 to 16). Results At five years after reimplantation, survival free of reinfection, aseptic rerevision, any rerevision, or any reoperation were 89% (95% CI 85.2 to 93.1), 93% (95% CI 89.3 to 96.1), 86% (95% CI 81.3 to 90.3), and 80% (95% CI 74.7 to 84.9), respectively. Dislocation accounted for most aseptic rerevisions (15/20). McPherson host C (HR 3.7 (95% CI 1.4 to 9.6); p = 0.007) and limb grade 3 (HR 3.3 (95% CI 1.0 to 11.1); p = 0.049) were significantly associated with an increased risk of reinfection. The mean Harris Hip Score at the latest follow-up was 76 (29 to 100). A total of 17 patients underwent revision or removal of a spacer for concerns about persistent infection and two for dislocation of the spacer. Eight patients underwent a non-rerevision reoperation during the spacer interval for wound drainage (n = 5), dislocation of the spacer (n = 2), and perispacer fracture (n = 1). A total of 26 spacer-related complications were treated nonoperatively (15 perispacer fractures, 11 dislocations). Dislocation of the spacer was strongly associated with dislocation after reimplantation (HR 6.2 (95% CI 2.3 to 16.9); p < 0.001). Conclusion This commercially available, partially intraoperatively fabricated articulating spacer showed excellent reinfection-free five-year survival (89%). Spacer-related fracture and dislocation each occurred in 5% of patients. Dislocation of the spacer significantly increased the risk of dislocation following reimplantation, supporting the use of higher-stability bearings in these high-risk patients. Cite this article: Bone Joint J 2026;108-B(9):1104–1112.

Background: Prior studies have reported higher rates of periprosthetic fracture, superficial infection, and neurologic deficit with the direct anterior approach (DAA), and higher rates of dislocation with the posterior approach (PA) for total hip arthroplasty (THA). Despite these differences, the overall clinical burden of complications between approaches remains unclear. The purpose of this study was to compare the profiles, severity, impact, and resolution of 5 clinically important complications between DAA and PA THA. Methods: A retrospective review was conducted of 11,783 consecutive primary THAs performed between 2010 and 2021 across 3 centers within a single healthcare system, using either the DAA (n = 4,451) or the PA (n = 7,332). Complications assessed included dislocation, infection, periprosthetic fracture (PPFx), aseptic loosening, and neurologic deficit. Severity was graded using the Clavien-Dindo classification (I = minor, V = death). Impact was defined by reoperation burden, and outcomes were categorized as resolved or persistent. Kaplan-Meier survivorship and propensity-weighted Cox proportional hazards models were used to compare complication risk. Results: The overall 1-year risk of surgical complications did not differ between DAA and PA (hazard ratio [HR], 0.89; 95% confidence interval [CI], 0.75-1.06; p = 0.208). Dislocation occurred more frequently with PA THA than DAA THA (1.9% vs. 0.4%; HR, 5.20; 95% CI, 3.04-8.90; p < 0.001). Superficial infections were more frequent with the DAA (1.6% vs. 0.8%; HR, 2.43; 95% CI, 1.68-3.53; p < 0.001). The risk of deep infection, PPFx, aseptic loosening, and neurologic deficit did not differ significantly between approaches. Among patients with complications, the proportion classified as severe (Clavien-Dindo III–V) was similar, and adjusted analyses showed no difference in the odds of severe complications (adjusted odds ratio 1.34 for PA vs DAA; 95% CI, 0.95-1.91; p = 0.099). Complication impact and resolution were likewise comparable. Conclusion: Although the profile of complications differed between DAA and PA THA, the severity, early clinical impact, and resolution of complications appeared similar. Notably, DAA was associated with a lower risk of dislocation and a higher risk of superficial infection compared with PA THA. Level of Evidence: Level III , Retrospective Comparative Study. See Instructions for Authors for a complete description of levels of evidence.

Aims Total knee arthroplasty (TKA) for end-stage osteonecrosis has historically been associated with concerns regarding aseptic loosening, and long-term data are limited. The purpose of this study was to update and expand our previous series with long-term follow-up, with specific emphasis on implant survivorship, risk factors for failure, complications, and clinical outcomes in a consecutive cohort of TKAs performed for primary and secondary osteonecrosis. Methods We retrospectively identified 295 consecutive TKAs in 266 patients for osteonecrosis performed at a single tertiary care academic institution from January 2002 to July 2022. Of these, 207 TKAs (70%) were performed for primary osteonecrosis, and 88 (30%) for secondary osteonecrosis. The predominant cause of secondary osteonecrosis was steroid use (59%; n = 52), followed by post-traumatic (25%; n = 22), radiation-induced (9%; n = 8), and alcohol-induced (7%; n = 6) osteonecrosis. Implant survivorship was analyzed as a time-to-event outcome using Kaplan-Meier estimation. The mean age was 61 years (18 to 93), with 67% being female (n = 197). The mean follow-up was nine years (2 to 20). Results The 15-year survivorship free of any revision for the entire cohort was 92% (95% CI 87 to 97), with similar rates between primary and secondary osteonecrosis (92% (95% CI 87 to 98) vs 93% (95% CI 87 to 100), respectively; p = 0.459). Varus-valgus constraint implant designs (HR 10.8 (95% CI 2.7 to 43.4); p < 0.001) and tibial stem use (HR 12.0 (95% CI 4.1 to 35.1); p < 0.001) were associated with an increased risk of any revision. The 15-year survivorship free of aseptic loosening was 97% (95% CI 93 to 100) for the entire cohort. Age under 65 years (HR 2.7 (95% CI 1.4 to 5.4); p = 0.005) and secondary osteonecrosis (HR 1.9 (95% CI 1.0 to 3.4); p = 0.044) were associated with an increased risk of any reoperation at 15 years. Conclusion TKA is a durable and reliable option for primary osteonecrosis at long-term follow-up. However, TKAs performed for secondary osteonecrosis carry a higher reoperation risk. Cite this article: Bone Joint J 2026;108-B(4):455–462.

Abstract Purpose Iliopsoas tendinitis following total hip arthroplasty (THA) has been described to result from acetabular component overhang as well as prominent femoral collars. Yet, a portion of patients experience iliopsoas tendinitis in the setting of well-positioned components. The purpose of this study was to assess anatomic factors predisposing to iliopsoas tendinitis after THA. Methods Patients with THAs performed at three academic institutions who subsequently underwent arthroscopic iliopsoas release were retrospectively reviewed from 2015 to 2025 and propensity matched in a 1:3 fashion to a control group of THAs without subsequent iliopsoas release. Controls were matched by age, surgery date, laterality, sex, surgical approach, and implanted femoral component. Patients with iliopsoas tendinitis and subsequent release (THA-IP) were evaluated for anterior acetabular component overhang and femoral collar overhang, when a collar was present. We also evaluated the absolute and relative profile of the lesser trochanter on anteroposterior radiographs, understanding that when less of the lesser trochanter is visualized, the trochanter is anatomically displaced posterolaterally, resulting in a more arduous route from the inner pelvic origin of the iliopsoas to its insertion on the femur. Results Forty-five patients (mean age: 57±11; 71% female; 19 direct anterior, 10 anterolateral, 16 posterior approach) undergoing THA-IP were analyzed and matched to 135 controls. Both groups demonstrated a median cup size of 54 mm and head size of 36 mm. Average time to iliopsoas release after THA was 4 years. Anterior cup overhang of &gt;2 mm was present in 49% of THA-IP patients, with 18% having collared femoral components, and 9% demonstrating collar overhang of &gt;2 mm. Overall, 19 THA-IP patients had &lt;2 mm of cup and collar overhang and 26 patients had &gt;2 mm of overhang. THA-IP patients with &lt;2 mm of cup and collar overhang had significantly greater relative posterolateralization of the lesser trochanter compared to those with overhang of &gt;2 mm (p=0.010) and to controls (p=0.037). Conclusion Visualizing “Less of the Lesser” on anteroposterior hip radiographs and associated posterolateralization of the lesser trochanter may be an anatomic risk factor for iliopsoas tendinitis following THA, even in the presence of satisfactorily positioned components.

Abstract » The coronal plane alignment of the knee (CPAK) classification is a practical and straightforward framework to define a patient’s constitutional coronal knee limb alignment and joint line obliquity. » Patients are assigned to one of nine phenotypes using two straightforward calculations; the arithmetic hip-knee-ankle angle (aHKA) and the arithmetic joint line obliquity (aJLO). » CPAK allows clear understanding of the geographical and gender variations in knee alignment, as well as the differing outcomes of knee reconstructive surgery, based on phenotype. » CPAK enables surgeons to tailor their alignment strategy to best fit a patient’s constitutional phenotype and avoid the drawbacks of a “one-size fits all” approach.

Background and Objectives: Patients undergoing major orthopedic surgery experience significant postoperative pain. Failure to provide adequate analgesia may impede early physical therapy and rehabilitation, which are important factors for maintaining joint range of motion and facilitating hospital dismissal. We examined the effect of a pre-emptive, multimodal, perioperative analgesic regimen emphasizing peripheral nerve block in patients undergoing total hip (THA) and total knee (TKA) arthroplasty. Perioperative outcomes and major postoperative complications were evaluated. Methods: One hundred consecutive patients undergoing primary or revision THA or TKA using the Mayo Clinic Total Joint Regional Anesthesia (TJRA) protocol were retrospectively reviewed. The TJRA protocol is a pre-emptive, multimodal, perioperative analgesic regimen emphasizing peripheral nerve block that was jointly developed by the Departments of Anesthesiology and Orthopedic Surgery. Identified patients were matched 1:1 with historical controls undergoing identical surgical procedures with traditional anesthetic techniques. Matching criteria included patient age, gender, surgeon, date of surgery, and American Society of Anesthesiologists physical status. Patient demographics, preoperative joint range of motion, and anesthetic management were recorded for each patient. The primary study outcome was hospital length of stay. Secondary outcome variables included time to ambulation, joint range of motion, and discharge eligibility. Postoperative verbal analog pain scores (VAS), opioid requirements, side effects, and perioperative complications were also documented. Results: One hundred patients underwent THA or TKA using the newly implemented Mayo Clinic TJRA protocol. Matched controls (n = 100) received intravenous patient-controlled analgesia with subsequent conversion to oral analgesics for postoperative pain management. TJRA patients had significantly shorter hospital lengths of stay (3.8 days v 5.0 days; P < .001), achieved discharge eligibility significantly sooner (1.7 ± 1.9 days earlier; P < .0001), and had improved joint range of motion (90° v 85°; P = .008) when compared with matched controls. TJRA patients had significantly improved postoperative analgesia, including lower VAS pain scores (postoperative day 0 through postoperative day 3; P < .001), and lower opioid requirements (postoperative day 0 to postoperative day 2; P = .04). Adverse outcomes such as postoperative urinary retention (50% v 31%; P < .001), and ileus formation (7% v 1%; P = .01) occurred more frequently among control patients. Conclusions: Patients undergoing THA or TKA using a comprehensive, pre-emptive, multimodal analgesic regimen emphasizing peripheral nerve block may have significantly improved perioperative outcomes, and fewer adverse events, when compared with patients receiving traditional intravenous opioids during the initial postoperative period. Improved perioperative outcomes include a shortened hospital length of stay, and a significant reduction in postoperative urinary retention and ileus formation.

Background: The U.S. Food and Drug Administration has approved a bupivacaine and meloxicam extended-release (ER) intra-articular injection for pain during total knee arthroplasty (TKA). However, the real-world evidence with regard to analgesic efficacy of that medication has been limited. This randomized clinical trial investigated the efficacy of this new medication compared with our standard periarticular injection for postoperative analgesia after primary TKA. Methods: Eligible patients undergoing primary, unilateral TKA for osteoarthritis at our academic center were enrolled. Patients were blinded and were randomized 1:1 to the bupivacaine-meloxicam ER (ZYNRELEF) injection group or the standard injection (ropivacaine, ketorolac, epinephrine) control group. A standardized, multimodal analgesic pathway was implemented. Numeric Rating Scale (NRS) pain scores and tallies of opioid consumption were collected. The primary outcome was the area under the curve (AUC) for NRS pain, adjusted for opioid consumption, over 72 hours. The minimal clinically important difference was considered to be 30%. Power analysis determined a minimum of 44 patients per group. The final groups included 53 patients in the experimental group and 48 patients in the control group. Results: Similar postoperative analgesia was observed, with an AUC for the adjusted NRS pain score up to 72 hours of 331 in the experimental group and 373 in the control group (p = 0.09). The mean maximum NRS pain scores were similar and reflected good, but not complete, analgesia. Scores were 3 to 5 on the day of the surgery, 4 to 6 on postoperative day (POD) 1, 5 to 6 on POD 2, and 4 to 5 on POD 3 (p > 0.05). One patient in the experimental group and 2 patients in the control group had early postoperative complications, none of which was deemed to be related to the analgesic choice. Conclusions: This randomized clinical trial demonstrated similar analgesia with a bupivacaine-meloxicam ER solution and a standard periarticular injection up to 72 hours after primary TKA. Cost, reimbursement, and convenience may ultimately prove to be more important than analgesic differences when choosing between these 2 effective options for managing postoperative pain. Level of Evidence: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.

AimsThe purpose of this study was to directly compare the Modular Dual Mobility (MDM) Mobile Bearing Hip System (Stryker, USA) and large femoral heads (LFHs) in revision total hip arthroplasties (THAs) at mid-term follow-up, with specific emphasis on survival free of re-revision for dislocation, any re-revision, dislocation, and the risk of metal-related complications.MethodsWe identified 299 revision THAs performed at a single tertiary care academic institution from March 2011 to July 2014. Aseptic loosening of the acetabular component (n = 65), dislocation (n = 58), and reimplantation as part of a two-stage exchange protocol (n = 57) were the most common reasons for index revision. MDM constructs were used in 123 cases, and LFHs were used in 176 cases. Mean age was 66 years (28 to 93), mean BMI was 31 kg/m2 (18 to 55), and 45% (n = 136) were female. Mean follow-up was seven years (2 to 12).ResultsThe ten-year survival free of re-revision for dislocation was 99% (95% CI 95 to 100) in the MDM cohort and 91% (95% CI 84 to 96) in the LFH cohort, with a significantly increased risk of re-revision for dislocation in the LFH cohort (HR 7.1 (95% CI 1.3 to 40.8); p = 0.023). The ten-year survival free of any re-revision was 92% (95% CI 82 to 99%) in the MDM cohort and 84% (95% CI 74 to 90) in the LFH cohort with a significantly increased risk of any re-revision in the LFH cohort (HR 2.6 (95% CI 1.1 to 5.9); p = 0.024). The ten-year survival free of any dislocation was 95% (95% CI 85 to 99) in the MDM cohort and 87% (95% CI 78 to 92) in the LFH cohort with a significantly increased risk of any dislocation in the LFH cohort (HR 2.7 (95% CI 1.1 to 6.3); p = 0.028). There were no re-revisions or reoperations for metallosis or corrosion in the MDM cohort.ConclusionIn this head-to-head comparison, revision THAs with a MDM construct safely and effectively lowered the risk of re-revision for dislocation, any re-revision, and any dislocation compared to LFH at mid-term follow-up. There were no re-revisions or reoperations for metallosis or corrosion in the MDM cohort.Cite this article: Bone Joint J 2025;107-B(1):58–64.

Background: Second-generation highly cross-linked polyethylene (HXLPE) has revolutionized total hip arthroplasty. However, the long-term risks and benefits of HXLPE in primary total knee arthroplasty (TKA) remain unknown. This randomized clinical trial evaluated implant survivorship, complications, radiographic results, and clinical outcomes of HXLPE and conventional ultra-high molecular weight polyethylene (UHMWPE) inserts in primary TKAs. Methods: We enrolled 518 patients (518 knees) who underwent primary TKA in 3 centers within 1 tertiary referral network. The mean age was 67 years, the mean body mass index was 32 kg/m 2 , and 58% of the patients were women. All of the patients underwent primary TKA with a cemented posterior-stabilized tibial insert and patellar resurfacing. Randomization proceeded via stratified dynamic allocation. The patients were blinded to their study group allocation: those in the control group (254 knees) underwent TKA with an UHMWPE insert (N2Vac; Stryker); those in the treatment group (264 knees) received an HXLPE insert (X3; Stryker). Kaplan-Meier survivorship, radiographic results, and clinical outcomes were assessed. This trial was registered with ClinicalTrials.gov. The mean follow-up was 11 years. Results: The 10-year overall survivorship free from any revision and from any reoperation was 96% and 94%, respectively. There were no differences in the risk of revision or reoperation between the groups (p > 0.05). There were a total of 19 revisions. Revision indications included periprosthetic joint infection (14 knees), instability (4 knees), and open reduction and internal fixation (ORIF) for a patellar fracture due to osteolysis around a UHMWPE insert (1 knee). There were no revisions due to polyethylene wear, osteolysis, or fracture of the post in the HXLPE group. The radiographic results and clinical outcomes were otherwise similar. Conclusions: Notably, no wear-related failures were identified in the HXLPE group, but there was 1 case of osteolysis in the UHMWPE group. Level of Evidence: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.

AimsThe prevalence of obesity is increasing substantially around the world. Elevated BMI increases the risk of complications following total hip arthroplasty (THA). We sought to evaluate trends in BMI and complication rates of obese patients undergoing primary THA over the last 30 years.MethodsThrough our institutional total joint registry, we identified 15,455 primary THAs performed for osteoarthritis from 1990 to 2019. Patients were categorized according to the World Health Organization (WHO) obesity classification and groups were trended over time. Cox proportional hazards regression analysis controlling for confounders was used to investigate the association between year of surgery and two-year risk of any reoperation, any revision, dislocation, periprosthetic joint infection (PJI), venous thromboembolism (VTE), and periprosthetic fracture. Regression was stratified by three separate groups: non-obese; WHO Class I and Class II (BMI 30 to 39 kg/m2); and WHO Class III patients (BMI ≥ 40 kg/m2).ResultsThere was a significant increase in the proportion of all obesity classes from 1990 to 2019, and the BMI values within each WHO class significantly increased over time. Risk of any reoperation did not change over time among non-obese or WHO Class I/II patients, but increased for WHO Class III patients (hazard ratio (HR) 1.04; p = 0.044). Risk of dislocation decreased over time for non-obese (HR 0.96; p < 0.001) and WHO Class I/II (HR 0.96; p = 0.002) patients, but did not change over time for WHO Class III (HR 0.94; p = 0.073) patients. Risks of any revision and PJI did not change over time for any group.ConclusionThe proportion of patients undergoing THA who are obese has increased dramatically at our institution between 1990 and 2019. Despite BMI values increasing within all WHO classes over time, two-year complication risks have remained stable or decreased in WHO Class I/II patients. However, continued efforts will be required to mitigate risks in the heaviest WHO Class III patients.Cite this article: Bone Joint J 2024;106-B(11):1223–1230.