Bisphosphonate Use May be Associated With an Increased Risk of Periprosthetic Hip Fracture.

BACKGROUND: Osteoporosis is common among patients undergoing primary total hip arthroplasty (THA). This study aimed to evaluate the effect of bisphosphonate treatment on osteoporotic patients undergoing primary THA. METHODS: Using a national database, 30,137 patients who had osteoporosis before primary elective THA were identified during 2010 to 2020. Patients undergoing nonelective THA and those using corticosteroids or other medications for osteoporosis were excluded. Bisphosphonate users and bisphosphonate naïve patients were matched 1:1 based on age, sex, Elixhauser comorbidity index, and a history of obesity, rheumatoid arthritis, tobacco use, and alcohol abuse. Kaplan-Meier and multivariate analyses were used to compare 2-year outcomes between groups. RESULTS: Among matched cohorts of 9,844 patients undergoing primary THA, bisphosphonate use was associated with a significantly higher 2-year rate of periprosthetic fracture (odds ratio 1.29, 95% confidence interval 1.04 to 1.61, P = .022). There was a trend toward increased risk of any revision with bisphosphonate use (odds ratio 1.19, confidence interval 1.00 to 1.41, P = .056). Rates of infection, aseptic loosening, dislocation, and mortality were not statistically different between bisphosphonate users and bisphosphonate-naïve patients. CONCLUSION: In osteoporotic patients, bisphosphonate use before primary THA is an independent risk factor for periprosthetic fracture. Additional longer-term data are needed to determine the underlying mechanism for this association and identify preventative measures.

Body Mass Index Does Not Drive the Risk for Early Postoperative Instability After Total Hip Arthroplasty: A Matched Cohort Analysis.

BACKGROUND: Instability remains the leading cause of revision following total hip arthroplasty (THA). The objective of the present investigation was to determine whether an elevated body mass index (BMI) is associated with an increased risk of instability after primary THA. METHODS: An administrative claims database was queried for patients undergoing elective, primary THA for osteoarthritis between 2010 and 2022. Patients who underwent THA for a femoral neck fracture were excluded. Patients who had an elevated BMI were grouped into the following cohorts: 25 to 29.9 (n = 2,313), 30 to 34.9 (n = 2,230), 35 to 39.9 (n = 1,852), 40 to 44.9 (n = 1,450), 45 to 49.9 (n = 752), and 50 to 59.9 (n = 334). Patients were matched 1:1 based on age, sex, and Elixhauser Comorbidity Index, as well as a history of spinal fusion, neurodegenerative disorders, and alcohol abuse, to controls with a normal BMI (20 to 24.9). A multivariate logistic regression controlling for age, sex, Elixhauser Comorbidity Index, and additional risk factors for dislocation was used to evaluate dislocation rates at 30 days, 90 days, 6 months, 1 year, and 2 years. Rates of revision for instability were similarly compared at 1 year and 2 years postoperatively. RESULTS: No significant differences in dislocation rate were observed between control patients and each of the evaluated BMI classes at all evaluated postoperative intervals (all P values > .05). Similarly, the risk of revision for instability was comparable between the normal weight cohort and each evaluated BMI class at 1 year and 2 years postoperatively (all P values > .05). CONCLUSIONS: Controlling for comorbidities and known risk factors for instability, the present analysis demonstrated no difference in rates of dislocation or revision for instability between normal-weight patients and those in higher BMI classes.

Clinical Outcomes and Survivorship of Lateral Unicompartmental Knee Arthroplasty: A Large Single Surgeon Cohort.

INTRODUCTION: Lateral unicompartmental knee arthroplasty (UKA) is an effective treatment for isolated lateral compartment osteoarthritis. However, due to the rarity of the procedure, long-term outcomes and survivorship are poorly understood. We report the clinical and radiographic outcomes after lateral UKA. METHODS: We retrospectively reviewed a consecutive series of patients who underwent lateral UKA by a single fellowship-trained arthroplasty surgeon from 2001 to 2021 with a minimum two year follow up. There were 161 knees in 153 patients (average age 69 years) that met inclusion criteria, with a mean follow up of 10.0 years (range 0.05 to 22.2). All patients underwent the procedure via a minimally invasive lateral parapatellar approach with a fixed-bearing implant. Patient demographics, complications, radiographic findings, patient-reported outcomes, and the need for revision surgery were evaluated. Survivorship was defined with the endpoint as revision of components. RESULTS: There were eight patients (5.0%) who underwent conversion to TKA for lateral UKA implant failure or progression of arthritis. There were three patients (1.9%) who underwent ipsilateral medial UKA due to medial compartment arthritis progression with preserved mechanical alignment and patello-femoral joint. There were eight additional procedures that did not require implant changes, including five irrigation and debridements for acute periprosthetic joint infection (PJI) (3.1%), two wound closures for dehiscence (1.3%), and one loose body removal (0.6%). CONCLUSION: Lateral UKA showed a survivorship rate of 98.0% at 5 years, 96.0% at 10 years, and 94.5% at 15 years. When including patients who underwent additional surgery for the progression of arthritis, survivorship was 97.4% at 5 years, 95.4% at 10 years, and 91.3% at 15 years. Lateral UKA should be seen as a durable treatment option for isolated lateral compartment osteoarthritis.

Fretting and Tribocorrosion of Modular Dual Mobility Liners: Role of Design, Microstructure, and Malseating.

BACKGROUND: Modular dual mobility (DM) bearings have a junction between a cobalt chrome alloy (CoCrMo) liner and titanium shell, and the risk of tribocorrosion at this interface remains a concern. The purpose of this study was to determine whether liner malseating and liner designs are associated with taper tribocorrosion. METHODS: We evaluated 28 retrieved modular DM implants with a mean in situ duration of 14.6 months (range, 1 to 83). There were 2 manufacturers included (12 and 16 liners, respectively). Liners were considered malseated if a distinct divergence between the liner and shell was present on postoperative radiographs. Tribocorrosion was analyzed qualitatively with the modified Goldberg Score and quantitatively with an optical coordinate-measuring machine. An acetabular shell per manufacturer was sectioned for metallographic analysis. RESULTS: There were 6 implants (22%) that had severe grade 4 corrosion, 6 (22%) had moderate grade 3, 11 (41%) had mild grade 2, and 5 (18.5%) had grade 1 or no visible corrosion. The average volumetric material loss at the taper was 0.086 ± 0.19 mm3. There were 7 liners (25%) that had radiographic evidence of malseating, and all were of a single design (P = .01). The 2 liner designs were fundamentally different from one another with respect to the cobalt chrome alloy type, taper surface finish, and shape deviations. Malseating was an independent risk factor for increased volumetric material loss (P = .017). CONCLUSIONS: DM tribocorrosion with quantifiable material loss occurred more commonly in malseated liners. Specific design characteristics may make liners more prone to malseating, and the interplay between seating mechanics, liner characteristics, and patient factors likely contributes to the shell/liner tribocorrosion environment. LEVEL OF EVIDENCE: Level III.

Intra-articular corticosteroid injections are associated with a dose-dependent risk of total knee arthroplasty at 5 years.

PURPOSE: Intra-articular corticosteroid injections (CSI) are used commonly for the non-operative management of patients with knee pain. Recent literature has raised concern for chondrotoxicity of CSI. The purpose of the present study is to evaluate for any dose-dependent association between CSI in non-osteoarthritic knees and subsequent total knee arthroplasty (TKA). METHODS: The Pearl Diver database identified patients with a diagnosis of knee pain without concomitant osteoarthritis who were administered CSI over a 2-year period. Patients were compared to matched and unmatched cohorts. The primary endpoint was the incidence of TKA at 5 years. Multivariable regression analysis was used to assess CSI quantity as an independent risk factor. RESULTS: 49,443 of 986,162 (5.0%) Patients diagnosed with knee pain without concomitant knee osteoarthritis who received at least one CSI were identified. At 5 years, there was a higher incidence of TKA in the matched injection cohort relative to the non-injection matched cohort (0.26 vs 0.13%; p < 0.001) and unmatched cohort (0.26 vs. 0.10%, p < 0.001). The quantity of CSI corresponded with an increased probability of TKA at 5 years; one injection: 0.22% (OR 1.23, 95% CI [0.87-1.74], p = 0.236); two injections: 0.39% (OR 1.98 CI [1.06-3.67], p = 0.03, three or more injections: 0.49% (OR 3.22 CI [1.60-6.48], p = 0.001). The average time to TKA after one CSI was 3.03 ± 2.29 years. This time was nearly halved with three CSI (1.78 ± 0.80 years, p < 0.001). CONCLUSIONS: Intra-articular corticosteroid injections in patients without knee osteoarthritis at the time of injection are associated with a dose-dependent risk of TKA at 5 years. CSI may not be as benign of a treatment modality as previously thought.

Cementless Total Knee Arthroplasty is Associated With Early Aseptic Loosening in a Large National Database.

BACKGROUND: Despite excellent longevity demonstrated in institutional studies, outcomes after cementless total knee arthroplasty (TKA) on a population level remain unknown. This study compares 2-year outcomes between cemented and cementless TKA using a large national database. METHODS: A large national database was used to identify 294,485 patients undergoing primary TKA from January 2015 to December 2018. Patients who had osteoporosis or inflammatory arthritis were excluded. Cementless and cemented TKA patients were matched one-to-one based on age, Elixhauser Comorbidity Index, sex, and year yielding matched cohorts of 10,580 patients. Outcomes at 90 days, 1 year, and 2 years postoperatively were compared between groups, and Kaplan-Meier analysis was used to evaluate implant survival rates. RESULTS: At 1 year postoperatively, cementless TKA was associated with an increased rate of any reoperation (odds ratio [OR] 1.47, 95% confidence interval [CI] 1.12-1.92, P = .005) compared to cemented TKA. At 2 years postoperatively, there was an increased risk of revision for aseptic loosening (OR 2.34, CI 1.47-3.85, P < .001) and any reoperation (OR 1.29, CI 1.04-1.59, P = .019) after cementless TKA. Two-year revision rates for infection, fracture, and patella resurfacing were similar between cohorts. CONCLUSION: In this large national database, cementless fixation is an independent risk factor for aseptic loosening requiring revision and any reoperation within 2 years after primary TKA.

Contralateral Total Hip Arthroplasty Staged Within Six Weeks Increases the Risk of Adverse Events Compared to Unilateral Surgery.

BACKGROUND: The ideal timing for bilateral total hip arthroplasty (THA) remains controversial. This study compared 90-day outcomes after simultaneous bilateral THA and contralateral surgery in staged bilateral THA to a matched cohort of unilateral procedures. METHODS: Patients undergoing primary, elective THA during 2015 to 2020 were reviewed in a national database. Of the 273,281 patients identified, 39,905 (14.6%) were bilateral. Patients were divided into cohorts of unilateral THA, simultaneous bilateral THA, and staged bilateral THA at 1 to 14 days, 15 to 42 days, 43 to 90 days, and 91 to 365 days. Bilateral THA cohorts were matched with unilateral THA patients based on demographics and comorbidities. Ninety-day outcomes after the second THA were compared between matched groups. RESULTS: Simultaneous bilateral THA resulted in higher rates of transfusion (odds ratio [OR] 4.43, 95% confidence interval 2.31-2.63, P < .001), readmission (OR 2.60, 2.01-3.39, P < .001), and any complication (OR 1.86, 1.55-2.24, P < .001) compared to unilateral THA. Contralateral THA staged at 1 to 14 days increased the risk of readmission (OR 1.83, 1.49-2.24, P < .001) and any complication (OR 1.45, 1.26-1.66, P < .001) relative to unilateral THA. Contralateral THA staged at 15 to 42 days increased the risk of periprosthetic joint infection (OR 3.15, 1.98-5.19, P < .001), readmission (OR 1.92, 1.55-2.39, P < .001), and any complication (OR 1.70, 1.46-1.97, P < .001). Contralateral THA staged beyond 42 days resulted in similar or decreased rates of adverse events relative to unilateral THA. CONCLUSIONS: Bilateral THA should be staged a minimum of 6 weeks apart in appropriately selected patients to avoid an increased risk of adverse events after the second THA compared to unilateral THA.

Over Half of All Medicare Total Knee Arthroplasty Patients Are Now Classified as an Outpatient-Three-Year Impact of the Removal From the Inpatient-Only List.

BACKGROUND: In 2018, Centers for Medicare & Medicaid Services removed total knee arthroplasty (TKA) from its inpatient-only list, triggering many unintended consequences. The purpose of this study was to determine how the impact of TKA removal affected the number of outpatient TKA patients, which patients were being labeled outpatient, and how outpatient classification affected discharge location and readmission rates. METHODS: Using a large administrative claims database, we reviewed a consecutive series of 216,365 primary TKA Medicare patients from 2015 to 2020. Patients who had an inpatient status (n = 63,356) were compared to patients who had an outpatient status (n = 38,510) from 2018 to 2020 based on demographics, comorbidities, discharge dispositions, and readmissions. RESULTS: In 2015, only 1.8% of TKA patients were designated as outpatients, but by 2020, 57.2% of Medicare TKA patients were classified as outpatients. A majority of patients (72%) who had an outpatient designation remained in the hospital for >24 hours (average length of stay was 2.7 days). Patients who had an outpatient status were discharged to skilled nursing facilities more frequently than patients who had an inpatient status (3.1 versus 2.0%, P < .001) with increased emergency visits (5.1 versus 3.9%, P < .001) and 90-day readmissions (2.2 versus 0.9%, P < .001). CONCLUSION: Over half of all Medicare TKA patients are being classified as outpatients 3 years following the policy to remove TKA from the inpatient-only list. Patients designated as outpatients had higher readmissions than those designated as inpatients. This policy should be re-evaluated in the context of failure to demonstrate safer discharge of Medicare patients who undergo TKA.

Invasive Gastrointestinal Endoscopy Following Total Joint Arthroplasty Increases the Risk for Periprosthetic Joint Infection.

BACKGROUND: The safety of postoperative colonoscopy and endoscopy following total joint arthroplasty (TJA) remains largely unknown. The objective of this study was to characterize the effect of gastrointestinal endoscopic procedures after TJA on the risk of postoperative periprosthetic joint infection (PJI). METHODS: Using a large national database, patients who underwent an endoscopic procedure (colonoscopy or esophagogastroduodenoscopy (EGD)) within 12 months after primary TJA were identified and matched in a 1:1 fashion based on procedure (primary total knee arthroplasty (TKA) versus total hip arthroplasty (THA)), age, sex, Charlson Comorbidity Index (CCI), and smoking status with patients who did not undergo endoscopy. A total of 142,055 patients who underwent endoscopy within 12 months following TJA (96,804 TKAs and 45,251 THAs) were identified and matched. The impact of timing of endoscopy relative to TJA on postoperative outcomes was assessed. Preoperative comorbidity profiles and 1-year complications were compared. Statistical analyses included Chi-squared tests and multivariate logistic regressions with outcomes considered significant at P < .05. RESULTS: Multivariate analyses revealed that endoscopy within 2 months following TKA and 1 month of THA was associated with a significantly increased odds of periprosthetic joint infection (odds ratio (OR): 1.29 [1.08-1.53]; P = .004; OR: 1.41 [1.01-1.90]; P = .033, respectively). Patients who underwent endoscopy greater than 2 months from the timing of their TKA and 1 month from THA were not at significantly greater risk of developing PJI. CONCLUSION: These data suggest that invasive endoscopic procedures should be delayed if possible by at least 2 months following TKA and 1 month following THA to minimize the risk of PJI.

Preoperative Opioids and the Dose-Dependent Effect on Outcomes After Total Hip Arthroplasty.

BACKGROUND: The purpose of this study is to identify the preoperative daily opioid dose associated with increased complications after primary total hip arthroplasty (THA). METHODS: Primary THA patients in the Humana claims database (2007-2020) with an opioid prescription within 3 months prior to surgery were identified. Patients were stratified based on daily opioid dose: Tier 1, <5 milligram morphine equivalents (MME); Tier 2, 5-10 MME; Tier 3, 11-25 MME; Tier 4, 26-50 MME; Tier 5, >50 MME. Each tier was matched 1:1 to opioid-naïve patients. Emergency department (ED) visits, readmissions, and postoperative complications were compared. RESULTS: In total, 67,719 patients using preoperative opioids were identified and matched. 17.0% of patients using preoperative opioids visited the ED within 90 days, compared to 13.3% of opioid-naïve patients (P < .001). About 9.5% of patients using preoperative opioids were readmitted within 90 days, compared to 7.4% of opioid-naïve patients (P < .001). When stratified by tier, opioid users in all tiers had higher risk of ED visits and readmission. Rates of superficial infection, periprosthetic joint infection, and dislocation were increased in patients taking preoperative opioids in Tiers 2 through 5. Patients in Tiers 3 through 5 had an increased risk of revision surgery. CONCLUSION: Preoperative opioid use is associated with a dose-dependent increase in complications after THA. Just one 5 mg hydrocodone tablet daily leads to a significant increase in ED visits and readmission, while higher doses are associated with dislocation, superficial infection, periprosthetic joint infection, and revision surgery. Continued education regarding the harmful effects of opioids prescribed for the nonoperative treatment of osteoarthritis is still needed. LEVEL OF EVIDENCE: Level III.

Daily Dose of Preoperative Opioid Prescriptions Affects Outcomes After Total Knee Arthroplasty.

BACKGROUND: The use of preoperative opioids is associated with complications after total knee arthroplasty (TKA), but the dosing threshold that constitutes this risk is not known. The purpose of this study was to identify the preoperative daily opioid dose associated with increased complications after primary TKA. METHODS: Patients who underwent primary TKA in the Humana claims database (2007-2016) with an opioid prescription within 3 months before surgery were identified. All opioids prescribed within 3 months before TKA were converted to milligram morphine equivalents. Patients were stratified based on daily opioid dose: tier 1) <10, tier 2) 10-25, tier 3) 25-50, tier 4) >50 milligram morphine equivalents. Patients were matched to opioid-naïve patients by comorbidities, age, and gender. Emergency department (ED) visits, readmissions, and surgical complications were compared. RESULTS: A total of 20,019 patients using preoperative opioids were identified and matched. ED visits and readmissions within 90 days were significantly higher in opioid users in all tiers (relative risk (RR) of ED visit: 1.25, 1.28, 1.34, and 1.25, respectively; readmission: 1.13, 1.17, 1.22, and 1.19, respectively). Rates of prosthetic joint infection were increased in opioid users in tiers 2, 3, and 4, and the risk increased in a dose-dependent manner (RR 1.37, 1.39, and 1.50, respectively). Patients in tier 4 had an increased risk of revision surgery (RR 1.44) at 2 years. CONCLUSION: Preoperative opioid use is associated with a dose-dependent increase in postoperative complications after TKA. Just two 5mg hydrocodone tablets daily lead to increased ED visits and readmission. Higher doses are associated with an increased risk of prosthetic joint infection and revision surgery.

Incidence of meniscal injury and chondral pathology in anterior tibial spine fractures of children.

BACKGROUND: Pediatric avulsion fractures of the anterior tibial spine are injuries similar to anterior cruciate ligament injuries in adults. Sparse data exists on the association between anterior tibial spine fractures (ATSFs) and injury to the meniscus or cartilage of the knee joint in children. This research presents a retrospective review of clinical records, imaging, and operative reports to characterize the incidence of concomitant injury in cases of ATSFs in children. The purpose of this study was to better delineate the incidence of associated injuries in fractures of the anterior tibial spine in the pediatric population. METHODS: We identified 58 patients who sustained an ATSF and met inclusion criteria for this study between 1996 and 2011. The subjects were separated by the Myers and McKeever classification into type I, II, and III fractures, and each of these were subclassified by associated injury pattern. RESULTS: 59% of children with an ATSF had an associated soft tissue or other bony injury diagnosed by magnetic resonance imaging or arthroscopy. The most prevalent associated injuries were meniscal entrapment, meniscal tears, and chondral injury. We found no meniscal or chondral injury associated with type I fractures. Twenty-nine percent of type II injuries demonstrated meniscal entrapment, 33% showing meniscal tears. Seven percent demonstrated chondral injury. Forty-eight percent of type III fractures had entrapment, whereas 12% showed meniscal tears. Eight percent had a chondral injury. CONCLUSIONS: A majority (59%) of displaced ATSF had either concomitant meniscal, ligamentous, or chondral injury. This finding suggests that magnetic resonance imaging evaluation is an important aspect of the evaluation of these injuries, particularly in type II and type III patterns. To date, this study reports the largest number of patients to evaluate the specific question of concomitant injuries in ATSFs in the pediatric population. LEVEL OF EVIDENCE: Level IV.

Step-cut osteotomy of the anterior superior iliac spine for increased visualisation in the Levine approach for Bernese periacetabular osteotomy surgery.

BACKGROUND: Hip dysplasia can lead to pain and dysfunction in the young adult. Acetabular undercoverage leads to abnormal joint loading and results in joint degeneration, accelerating need for arthroplasty in this patient population. Conceptually, treatment focuses on increasing acetabular coverage in the form of periacetabular osteotomy. The procedure can be performed through the iliofemoral approach, and performing an anterior superior iliac spine (ASIS) osteotomy can enhance the visualisation in this approach. Several techniques have been described for ASIS osteotomy. AIM: The purpose this study was to report on step-cut technique for ASIS osteotomy during the Bernese periacetabular osteotomy procedure to enhance visualisation when utilising the iliofemoral approach. SURGICAL TECHNIQUE: This step-cut technique enhances stability at the osteotomy site, and minimises soft tissue dissection to reduce pain and assists with maintaining a stable fixation construct postoperatively. RESULTS: There were no nonunions and minimal morbidity to the lateral femoral cutaneous nerve injury in cohort of 86 patients while utilising this technique. CONCLUSIONS: We recommend using this step-cut ostetomy of the ASIS during Bernese periactetabular osteotomy for benefit of increasing exposure while maintaining a low complication profile.

The Ideal Timing of Bilateral Total Knee Arthroplasty: Simultaneous Versus Staged.

Objectives: The ideal timing for patients undergoing bilateral total knee arthroplasty (TKA) remains unknown. The purpose of this study was to compare 90-day outcomes between unilateral, simultaneous bilateral, and staged bilateral TKA. Methods: The PearlDiver database was used to retrospectively identify 231,119 patients undergoing primary TKA during 2015-2020, of which 67,956 (29.4%) were bilateral. Bilateral TKA patients were divided into cohorts of simultaneous bilateral TKA and staged bilateral TKA at 1-14 days, 15-30 days, 31-90 days, and 91-365 days. Each bilateral TKA cohort underwent one-to-one matching with unilateral TKA patients based on age, gender, year, Elixhauser Comorbidity Index (ECI), and a history of obesity, diabetes, and tobacco use. Ninety-day outcomes were compared between matched groups via univariate and multivariate analysis. In staged bilateral TKA groups, outcomes were collected beginning after the second TKA. Results: Compared to unilateral TKA, simultaneous bilateral TKA was associated with higher rates of venous thromboembolism (VTE; odds ratio [OR] 1.28, 95% confidence interval [CI] 1.07-1.54, p=0.007), acute kidney injury (AKI; OR 1.47, CI 1.17-1.84, p=0.001), blood transfusion (OR 6.81, CI 5.43-8.65, p<0.001), and any complication (OR 1.63, CI 1.49-1.78, p<0.001). Staged bilateral TKA at any time interval studied was associated with a similar or decreased risk of individual complications, emergency department visits, readmissions, reoperations, and any complication relative to unilateral TKA. Conclusion: Simultaneous bilateral TKA is associated with an increased risk of adverse events compared to unilateral TKA. However, bilateral TKA staged at a short interval appears safe in appropriately selected patients.

Intra-articular corticosteroids associated with increased risk of total hip arthroplasty at 5 years.

BACKGROUND: Intra-articular corticosteroid injections are commonly administered for hip pain. However, guidelines are conflicting on their efficacy, particularly in patients without arthritis. This study assessed for an association of corticosteroid injections and the incidence of total hip arthroplasty at 5 years. METHODS: Patients with a diagnosis of hip pain without femoroacetabular osteoarthritis who were administered an intra-articular corticosteroid injection of the hip within a 2-year period were identified from the Mariner PearlDiver database. Patient were matched to patients with a diagnosis of hip pain who did not receive an injection. 5-year incidence of total hip arthroplasty was compared between matched patients who received an intra-articular corticosteroid injection and those who did not. RESULTS: 2,540,154 patients diagnosed with hip pain without femoroacetabular arthritis were identified. 25,073 (0.9%) patients received a corticosteroid injection and were matched to an equal number of control patients. The incidence of total hip arthroplasty (THA) at 5-year-follow up was significantly higher for the corticosteroid cohort compared to controls (1.1% vs. 0.5%; p < 0.001). The incidence and risk of THA increased along with number of injections (1 injection: 0.8%, OR 1.37; 95% CI, 1.34-1.42; p < 0.001, 2 injections: 1.1%; OR 1.45; CI, 1.40-1.50; p < 0.001, ⩾3 injections: 1.5%; OR 1.48; CI, 1.40-1.56; p < 0.001). CONCLUSIONS: There may be a dose-dependent association of corticosteroid injections and a greater risk of total hip arthroplasty at 5 years. These results along with the conflicting guidelines on the efficacy of intra-articular steroids for hip pain should prompt physicians to consider osteoarthritis progression that may occur in the setting of corticosteroid injections in non-arthritic hips.

A Novel Fluoroscopic View for Improved Assessment of the Safety of the Posterosuperior Screw in Femoral Neck Fracture Fixation.

BACKGROUND: The purpose of the present study was to determine specific fluoroscopic views of the femoral neck to accurately identify partially extraosseous ("in-out-in"; IOI) placement of the posterosuperior screw for fixation of femoral neck fractures. METHODS: A 3.2-mm guide pin was placed in the posterosuperior aspect of 2 synthetic femur models: 1 entirely intraosseous and 1 IOI. Sequential fluoroscopic images were made at 5° intervals in order to identify which fluoroscopic projections identified IOI guide pin placement. These images were utilized to inform screw placement and assessment in the second phase of the study, which involved the use of cadaveric specimens. In Phase II, the posterosuperior screw of the inverted triangle was placed in 10 cadaveric specimens with use of a standard posteroanterior fluoroscopic view and 1 of 2 lateral views, either (1) neck in line with the shaft, i.e., 0° lateral; or (2) a -15° rollunder view. The final fluoroscopic views (i.e., the posteroanterior and multiple lateral and oblique views) were randomized and blinded for review by 10 orthopaedic residents and 5 attending orthopaedic traumatologists. Specimens were stripped of soft tissue and inspected for screw perforation. RESULTS: Overall accuracy of respondents was 68.8%, with no difference between the attending traumatologists (71.8%) and resident surgeons (67.4%; p = 0.173). Interobserver reliability was moderate (κ = 0.496). Dissection identified that 4 (40%) of 10 screws were extraosseous. All of the extraosseous screws were placed with use of the 0° lateral view. The -15° rollunder lateral view was the most sensitive (81.7%) and specific (92.2%) view for identifying IOI screw placement. CONCLUSIONS: Surgeons often utilize the standard posteroanterior and 0° lateral fluoroscopic views to safely place screws; however, many of these screws are IOI. The addition of a -15° rollunder lateral view significantly improved identification of IOI screws in the posterosuperior femoral neck. Unidentified IOI screw placement may result in damage to the blood supply of the femoral head.

Periprosthetic Tibial Plateau Fractures After Unicompartmental Knee Arthroplasty Are Successfully Treated With Open Reduction and Internal Fixation.

Periprosthetic tibial fractures after unicompartmental knee arthroplasty (UKA) are rare but devastating events. Given the relative infrequency of these injuries, treatment strategies are not well defined. The goal of this retrospective case series is to report the findings for a series of patients who underwent open reduction and internal fixation (ORIF) of periprosthetic fracture after UKA, including radiographic alignment, Knee Society Score (KSS), and failure rate. Patients were identified by the International Classification of Diseases code for periprosthetic tibial plateau fractures. Electronic medical records and radiographs were retrospectively reviewed. Fracture patterns and coronal and sagittal alignment of UKA components were measured on radiographs. Clinical outcomes, including range of motion assessment, visual analog scale pain score, and KSS, were collected at final follow-up. Eight patients satisfied the inclusion criteria for this study. Fractures occurred at a median of 14 days (range, 5-52 days) after UKA, and all showed a vertical shear pattern that exited at the meta-diaphyseal junction. Of the 8 fractures, 7 (87.5%) healed to radiographic and clinical union after the initial ORIF. One patient required reoperation for hardware failure. Mean visual analog scale pain score and KSS at final follow-up were 3 and 85±14, respectively. Periprosthetic tibial plateau fractures after UKA commonly occur as a vertical shear fracture exiting at the metadiaphyseal junction. The use of ORIF with a 3.5-mm plate in buttress mode is a reliable method for treatment of these fractures. Restoration of alignment and motion is achievable, but residual pain may affect patient-reported outcome scores. [Orthopedics. 2022;45(5):287-292.].

Free Fibular Flap and Fibular Graft Double-Strut Tunneling to Fill a Large Tibial Plateau Defect.

Introduction: Bony defects resulting from trauma, osteomyelitis, and tumor resection pose significant reconstructive challenges. Free fibular flaps (FFFs) are an excellent option, especially for large defects in the tibia. Case presentation: In this article, the authors review a case of a 60-year-old male who underwent FFF and fibular graft double-strut tunneling to fill a large tibial plateau defect. Conclusion: The use of the FFF provides an excellent option for reconstructing long bone large defects (defects > 6 cm). The case presented in this report indicates an expanded application of this technique in treating defects secondary to chronic osteomyelitis in infected tibial plateau nonunion.

Costs of unicompartmental compared with total knee arthroplasty : a matched cohort study over ten years.

AIMS: The aim of this study was to compare ten-year longitudinal healthcare costs and revision rates for patients undergoing unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). METHODS: The Humana database was used to compare 2,383 patients undergoing UKA between 2007 and 2009, who were matched 1:1 from a cohort of 63,036 patients undergoing primary TKA based on age, sex, and Elixhauser Comorbidity Index. Medical and surgical complications were tracked longitudinally for one year following surgery. Rates of revision surgery and cumulative mean healthcare costs were recorded for this period of time and compared between the cohorts. RESULTS: Patients undergoing TKA had significantly higher rates of manipulation under anaesthesia (3.9% vs 0.9%; p < 0.001), deep vein thrombosis (5.0% vs 3.1%; p < 0.001), pulmonary embolism (1.5% vs 0.8%; p = 0.001), and renal failure (4.2% vs 2.2%; p < 0.001). Revision rates, however, were significantly higher for UKA at five years (6.0% vs 4.2%; p = 0.007) and ten years postoperatively (6.5% vs 4.4%; p = 0.002). Longitudinal-related healthcare costs for patients undergoing TKA were greater than for those undergoing UKA at one year ($24,771 vs $22,071; p < 0.001) and five years following surgery ($26,549 vs $25,730; p < 0.001); however, the mean costs of TKA were comparable to UKA at ten years ($26,877 vs $26,891; p = 0.425). CONCLUSION: Despite higher revision rates, patients undergoing UKA had lower mean healthcare costs than those undergoing TKA up to ten years following the procedure, at which time costs were comparable. In the era of value-based care, surgeons and policymakers should be aware of the costs involved with these procedures. UKA was associated with fewer complications at one year postoperatively but higher revision rates at five and ten years. While UKA was significantly less costly than TKA at one and five years, costs at ten years were comparable with a mean difference of only $14. Lowering the risk of revision surgery should be targeted as a source of cost savings for both UKA and TKA as the mean related healthcare costs were 2.5-fold higher in patients requiring revision surgery. Cite this article: Bone Joint J 2021;103-B(6 Supple A):23-31.

Similar 90-day outcomes among inpatient and outpatient arthroplasties : a single-surgeon matched cohort analysis.

AIMS: The proportion of arthroplasties performed in the ambulatory setting has increased considerably. However, there are concerns whether same-day discharge may increase the risk of complications. The aim of this study was to compare 90-day outcomes between inpatient arthroplasties and outpatient arthroplasties performed at an ambulatory surgery centre (ASC), and determine whether there is a learning curve associated with performing athroplasties in an ASC. METHODS: Among a single-surgeon cohort of 970 patients who underwent arthroplasty at an ASC, 854 (88.0%) were matched one-to-one with inpatients based on age, sex, American Society of Anesthesiologists (ASA) grade, BMI, and procedure (105 could not be adequately matched and 11 lacked 90-day follow-up). The cohort included 281 total hip arthroplasties (THAs) (32.9%), 267 unicompartmental knee arthroplasties (31.3%), 242 primary total knee arthroplasties (TKAs) (28.3%), 60 hip resurfacings (7.0%), two revision THAs (0.3%), and two revision TKAs (0.3%). Outcomes included readmissions, reoperations, visits to the emergency department, unplanned clinic visits, and complications. RESULTS: The inpatient and outpatient groups were similar in all demographic variables, reflecting successful matching. The reoperation rate was 0.9% in both cohorts (p = 1.000). Rates of readmission (2.0% inpatient vs 1.6% outpatient), any complications (5.9% vs 5.6%), minor complications (4.2% vs 3.9%), visits to the emergency department (2.7% vs 1.4%), and unplanned clinic visits (5.7% vs 5.5%) were lower in the outpatient group but did not reach significance with the sample size studied. A learning curve may exist, as seen by significant reductions in the reoperation and overall complication rates among outpatient arthroplasties over time (p = 0.032 and p = 0.007, respectively), despite those in this group becoming significantly older and heavier (both p < 0.001) during the study period. CONCLUSION: Arthroplasties performed at ASCs appear to be safe in appropriately selected patients, but may be associated with a learning curve as shown by the significant decrease in complication and reoperation rates during the study period. Cite this article: Bone Joint J 2021;103-B(7 Supple B):84-90.