Mid term outcomes of a novel metaphyseal porous titanium cone in revision total knee arthroplasty.

Introduction: Bone loss is present in all revision total knee arthroplasties. Metaphyseal cones allow surgeons to negotiate loss of femoral and tibial bone stock while obtaining stable bony fixation. This study examines the mid-term functional and radiographic outcomes in patients undergoing revision total knee arthroplasty (rTKA) utilizing a novel metaphyseal cone system. Methods: This multicenter retrospective study examined all patients who received a porous, titanium tibial or femoral cone at four academic urban tertiary care institutions and presented for a minimum two-year follow-up. Patient demographics, indications for revision surgery, knee range-of-motion (ROM), re-revision rates, radiographic measurements, bone defect per AORI classification, and implant osseointegration were evaluated according to the Knee Society total knee arthroplasty (TKA) radiographic evaluation system. Results: One-hundred and four patients received 128 cone implants (84 tibial, 44 femoral cones; 24 patients with simultaneous ipsilateral tibial and femoral cones; 104 rTKA) with mean follow-up of 32.75 ± 6.54 months. The pre-operative main revision indications were aseptic loosening 36 (34.61 %), periprosthetic infection (PJI) 23 (22.11 %) and instability 18 (17.3 %). Thirteen rTKA underwent re-revision surgery: 3 for acute PJI, 4 for chronic PJI, 5 for instability, and 1 for mechanical failure of a hinged system. At most recent radiographic follow-up available, all unrevised cones had evidence of osteointegration and no visible implant migration.All-cause re-operation free survivorship was 87.5 % (91/104), and all-cause cone implant survivorship was 96.09 % (123/128 cones) at 2-year follow-up. Conclusion: This study demonstrates excellent mid-term outcomes of a novel porous, titanium metaphyseal cone in patients with large bone defects undergoing complex revision TKA. Level of evidence: IV, case series.

The Cam-Post Dislocation in Posterior-Stabilized Total Knee Arthroplasty A Case Series.

Cam-post dislocations are a unique complication of total knee arthroplasty (TKA) designs that utilize a cam-post mechanism, representing an extreme form of deep flexion instability. They are rare complications and are poorly defined in the existing literature. The purpose of this case study is to present a series of six cam-post dislocation cases to improve understanding of this complication and its mechanism, presentation, and available treatment options. All patients experienced cam-post dislocations after a deep flexion moment that were identified clinically and confirmed radiographically. Affected implants included both primary and revision components and all utilized a cam-post mecha- nism. Three patients underwent revision surgery whereas the remaining three were treated with closed reduction only. Cam-post dislocations are rare complications of posterior- stabilized TKA that should be understood and recognized by adult reconstruction surgeons. Closed reduction may be achieved with hyperflexion and anterior drawer or with hyperextension, but these patients may ultimately require a revision procedure.

Assessment of Healthcare Delivery Systems in Orthopaedic Surgery: A Large Retrospective Cohort Evaluation.

INTRODUCTION: The purpose of this study was to assess how quality and volume of common orthopaedic care varies across private, municipal, and federal healthcare delivery systems (HDSs). METHODS: Hip and knee arthroplasty, knee and shoulder arthroscopy, and hip fracture repair were audited over a two-year period. Electronic medical records were reviewed for demographics, diagnosis, lengths of stay (LoSs), surgical wait times, inpatient complication, readmission, and revision surgery rates. Multivariate regression controlled for differences in age, sex, diagnosis, and Charlson Comorbidity Index to determine how HDS correlated with surgical wait time, length of stay, complication rates, readmission, and revision surgery. RESULTS: The 5,696 included patients comprise 87.4% private, 8.6% municipal, and 4.0% federal HDSs. Compared with private HDS for arthroplasty, federal surgical wait times were 18 days shorter (95% CI = 9 to 26 days, P < 0.001); federal LoS was 4 days longer (95% CI = 3.6 to 4.3 days, P < 0.001); municipal LoS was 1 day longer (95% CI = 0.8 to 1.4, P < 0.001); municipal 1-year revision surgery odds were increased (odds ratio [OR] = 2.8, 95% CI = 1.3 to 5.4, P = 0.045); and complication odds increased for municipal (OR = 12.2, 95% CI = 5.2 to 27.4, P < 0.001) and federal (OR = 12.0, 95% CI = 4.5 to 30.8, P < 0.001) HDSs. Compared with private HDS for arthroscopy, municipal wait times were 57 days longer (95% CI = 48 to 66 days, P < 0.001) and federal wait times were 34 days longer (95% CI = 21 to 47 days, P < 0.001). Compared with private HDS for fracture repair, municipal wait times were 0.6 days longer (95% CI = 0.2 to 1.0, P = 0.02); federal LoS was 7 days longer (95% CI = 3.6 to 9.4 days, P < 0.001); and municipal LoS was 4 days longer (95% CI = 2.4 to 4.8, P < 0.001). Only private HDS fracture repair patients received bone health consultations. DISCUSSION: The private HDS provided care for a markedly larger volume of patients seeking orthopaedic care. In addition, private HDS patients experienced reduced surgical wait times, LoSs, and complication odds for inpatient elective cases, with better referral patterns for nonsurgical orthopaedic care after hip fractures within the private HDS. These results may guide improvements for federal and municipal HDSs.

Dual Mobility in Total Hip Arthroplasty.

Dual mobility designs in total arthroplasty allow for increased range of motion prior to impingement and dislocation. While valuable for reducing dislocation, dual mobility has its own unique complication profile that includes intraprosthetic dislocation, corrosion, and femoral notching. Despite these relatively rare complications, dual mobility articulations are valuable options for patients at higher risk of dislocation-both early and contemporary reports on dual mobility in total hip arthroplasty suggest that it can reduce the risk of dislocation without leading to unacceptable rates of complication or early revision. Cost analyses and longer follow-up studies on newer dual mobility designs will help determine the future of dual mobility in total hip arthroplasty.

Improved Sexual Function After Total Hip and Knee Arthroplasty for Osteoarthritis.

Osteoarthritis of the hip and knee is known to affect sexual activity. For patients with osteoarthritis, pain during sexual activity can lead to decreased quality of life and other associated health issues. The authors designed a prospective study to evaluate the effect of total hip arthroplasty and total knee arthroplasty on the psychosocial and physical aspects of sexuality pre- and postoperatively. Between April 2009 and December 2011, patients received questionnaires in the mail preoperatively. They were asked to return the preoperative questionnaire before surgery and the postoperative questionnaire 6 months after surgery. Data were analyzed to evaluate the psychosocial and physical aspects of sexuality and participants' subjective assessment of their appearance. Preoperatively, 91% and 67% of patients reported psychosocial and physical issues, respectively. After the arthroplasty procedure, 84% (P<.001) and 47% (P<.001) of patients reported improvement psychosocially and physically, respectively. Of the patients, 16% reported that arthroplasty adversely affected sexual function, with their predominant fear being joint damage (63%). A greater number of women and patients undergoing hip procedures reported improvement in sexual activity after surgery compared with men (P=.02) and patients undergoing knee procedures (P=.002). Both hip and knee osteoarthritis and arthroplasty had a significant effect on overall sexual function-psychosocially, physically, and in terms of patients' assessment of their external appearance-with higher rates of improvement seen after hip arthroplasty. Because of the effect of osteoarthritis and arthroplasty on sexual function, this topic should be addressed both pre- and postoperatively. [Orthopedics. 2021;44(2):111-116.].

Aseptic Loosening of Porous Metaphyseal Sleeves and Tantalum Cones in Revision Total Knee Arthroplasty: A Systematic Review.

Bone loss often complicates revision total knee arthroplasty (TKA). Management of metaphyseal defects varies, with no clearly superior technique. Two commonly utilized options for metaphyseal defect management include porous-coated metaphyseal sleeves and tantalum cones. A systematic review was conducted according to the international Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We combined search terms "Total knee arthroplasty" AND/OR "Sleeve," "Cone" as either keywords or medical subject heading (MeSH) terms in multiple databases according to PRISMA recommendations. All retrieved articles were reviewed and assessed using defined inclusion and exclusion criteria. A total of 27 studies (12 sleeves and 15 cones) of revision TKAs were included. In the 12 studies on sleeve implantation in revision TKAs, 1,617 sleeves were implanted in 1,133 revision TKAs in 1,025 patients. The overall rate of reoperation was 110/1,133 (9.7%) and the total rate of aseptic loosening per sleeve was 13/1,617 (0.8%). In the 15 studies on tantalum cone implantation in revision TKAs, 701 cones were implanted into 620 revision TKAs in 612 patients. The overall rate of reoperation was 116/620 (18.7%), and the overall rate of aseptic loosening per cone was 12/701 (1.7%). Rates of aseptic loosening of the two implants were found to be similar, while the rate of reoperation was nearly double in revision TKAs utilizing tantalum cones. Variability in the selected studies and the likely multifactorial nature of failure do not allow for any definitive conclusions to be made. This review elucidates the necessity for additional literature examining revision TKA implants.

Does femoral morphology and stem alignment influence outcomes of cementless total hip arthroplasty with proximally coated double-tapered titanium stems?

INTRODUCTION: Stem subsidence and thigh pain can cause significant patient dissatisfaction after cementless THA. The purpose of this study was to examine the effect of proximal-femoral morphology and stem alignment on clinical outcomes using a double-tapered, cementless titanium femoral component. METHODS: We retrospectively reviewed 281 consecutive, primary THAs from 2012 to 2014 with a mean follow-up of 4 years. Preoperative radiographs were used to assess femoral neck shaft angle (FNS), canal flare index (CFI), Dorr classification, and greater trochanter (GT) overhang. Postoperative radiographs were used to determine stem alignment and 6-week follow-up radiographs were used to determine subsidence. Clinical outcomes included thigh pain, leg-length discrepancy (LLD), patient-reported outcome measures (PROMs) and revision surgeries. RESULTS: 271 stems (96%) did not subside (<4 mm) and 10 (4%) showed evidence of subsidence (>4 mm). Subsidence was significantly associated with subsequent revision surgery (p < 0.01). 278 stems (99%) were in neutral alignment and 3 in varus (1%). Alignment did not significantly influence subsidence, thigh pain, LLD, revisions, or PROMs. Femoral morphology measures (FNS, CFI, Dorr classification, and GT overhang) were not significantly associated with stem alignment, subsidence, LLD, or revisions. CFI was significantly associated with intraoperative calcar fractures (p = 0.02). GT overhang was associated with thigh pain (p = 0.03) and FNS was inversely associated with postoperative HOOS scores. CONCLUSIONS: Subsidence and proximal-femoral morphology are potential sources of postoperative morbidity in certain cementless THA patients. In accordance with prior studies, CFI was identified as a potential risk factor for intraoperative calcar fractures. More research into preoperative femoral morphologies, such as GT overhang and FNS, is warranted as these may contribute to unsatisfactory results related to cementless THA.

Subsidence Following Revision Total Hip Arthroplasty Using Modular and Monolithic Components.

BACKGROUND: The ideal femoral component in revision total hip arthroplasty (rTHA) remains undetermined; however, tapered, fluted, titanium (TFT) stems are now widely used with favorable results in all types of revision scenarios. With both modular and monoblock TFT stem options, neither has been proven to be superior. Femoral stem subsidence has been linked to aseptic loosening, instability, and leg length discrepancy. This study aims to assess stem subsidence of modular and monoblock TFT stems at a single urban orthopedic specialty hospital within a tertiary academic medical center. METHODS: Electronic medical records of rTHAs performed between January 2013 and March 2018 utilizing modular and monoblock TFT stems were examined. Data collected included baseline demographics, surgical indication, femoral Paprosky classification, and stem subsidence at most recent follow up (3 months to 3 years). Two-sample t-tests and chi-squared tests were used for statistical analysis. RESULTS: A total of 186 patients (106 modular, 80 monoblock) were included in the analysis. Modular stems underwent significantly greater subsidence than monoblock stems at latest radiographic follow-up (3.9 ± 2.6 vs 2.3 ± 2.5 mm, P < .001). A significantly greater proportion of modular stems underwent >5 mm of subsidence at latest follow-up (29.2% vs 11.3%, P < .001). CONCLUSION: Monoblock TFT stems have displayed promising clinical results in prior studies, and now have been shown to decrease the incidence of postoperative subsidence. With the potential for stem subsidence to lead to aseptic loosening, limb length discrepancy, and instability, the orthopedic surgeon should weigh the risks and benefits of utilizing modular vs monoblock TFT stems in rTHA.

Total Knee Arthroplasty Is Safe in Jehovah's Witness Patients-A 12-Year Perspective.

Despite the evolution of blood management protocols, total knee arthroplasty (TKA) occasionally requires allogeneic blood transfusion. This poses a particular challenge for Jehovah's Witnesses (JW) who believe that the Bible strictly prohibits the use of blood products. The aim of this study was to compare JW and a matched-control cohort of non-JW candidates undergoing TKA to assess the safety using modern blood management protocols. Fifty-five JW patients (63 knees) who underwent TKA at our institution between 2005 and 2017 were matched to 63 non-JW patients (63 knees). Patient demographics, intraoperative details, and postoperative complications including in-hospital complications, revisions, and 90-day readmissions were collected and compared between the groups. Additionally, subgroup analysis was performed comparing JW patients who were administered tranexamic acid (TXA) between the two groups. Baseline demographics did not vary significantly between the study cohorts. The mean follow-up was 3.1 years in both the JW and non-JW cohorts. Postoperative complications, including in-hospital complications (7.9 vs. 4.8%; p = 0.47), revision TKA (1.6 vs. 1.6%; p = 1.00), and 90-day readmission (1.6 vs. 4.8%; p = 0.31) were not significantly different between the JW and non-JW groups. Subgroup analysis demonstrated JW patients who received TXA had a significantly lower decline in postoperative hemoglobin (Hgb) (8.6 vs. 14.0%; p < 0.01). At a follow-up of up to 12 years, JW patients who underwent TKA have outcomes equivalent to non-JW patients without the need for transfusion. Our findings support that surgeons are more likely to optimize JW patients preoperatively with iron and folate supplementation. Despite these variations in preoperative optimization efforts, no significant difference with regard to Hgb or hematocrit levels was demonstrated. Level of evidence is III, retrospective observational study.

Nonmodular Stems Are a Viable Alternative to Modular Stems in Revision Total Hip Arthroplasty.

BACKGROUND: Nonmodular and modular femoral stems have been associated with complications after revision total hip arthroplasty (rTHA). As such, the ideal femoral component for rTHA remains undecided. This study aims to report outcomes of titanium, tapered-fluted, modular and nonmodular femoral components in rTHA. METHODS: From January 1, 2013 to September 30, 2017, all rTHAs using modular or nonmodular femoral stems were identified. Demographic data including age, gender, and American Society of Anesthesiologists scores were collected. Surgical details including operative time and implant cost were also collected. Clinical outcomes including length of stay, dislocation, infection, fracture, reoperation, and re-revision were collected. Statistical analysis was performed using chi-square test and Student's t-test for all categorical and continuous variables, respectively. RESULTS: One hundred forty-six rTHA cases (103 modular and 43 nonmodular) were identified with an average follow-up of 29 months (range 3-59 months). Nonmodular stems had a significantly lower cost when compared to modular implants (modular stems 120.8% higher cost; P < .001). The surgical time of nonmodular components was significantly greater (193 minutes vs 163 minutes; P = .029). There were no differences observed in any other surgical details or clinical outcomes assessed, including length of stay (P = .323), rate of re-revision of the femoral implant (P = .389), rate of re-operation (P = .383), and postop complications (P = .241), including infection (P = .095), dislocation (P = .778), and fracture (P = .959). CONCLUSIONS: Nonmodular components provide encouraging clinical results with significantly lower costs compared to modular implants in rTHA. The use of titanium, tapered-fluted, nonmodular components may offer a more cost-effective approach to rTHA compared to their modular counterparts.

Salvage of failed internal fixation of intertrochanteric hip fractures: clinical and functional outcomes of total hip arthroplasty versus hemiarthroplasty.

BACKGROUND: Failed internal fixation of intertrochanteric (IT) hip fractures presents a significant challenge in the elderly, osteoporotic population. Conversion total hip arthroplasty (cTHA) and hemiarthroplasty (cHA) are both accepted salvage operations for failed IT fracture fixation, though limited clinical data exist regarding the optimal treatment between these procedures. METHODS: A systematic review of 3 databases (PubMed, Cochrane, and Embase) was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Inclusion criteria were English-language studies that compared clinical or functional outcomes after failed fixation of IT fractures with total hip arthroplasty and hemiarthroplasty in adult subjects (>18 years of age). Data regarding research design, surgical technique, and clinical or functional outcomes were obtained and analyzed from eligible studies using a Mantel-Haenszel random-effects analysis model. RESULTS: Six studies with 188 patients (100, total hip arthroplasty; 88, hemiarthroplasty) met inclusion and exclusion criteria. There was no significant difference between cTHA and cHA for postoperative dislocation, reoperation, infection, intraoperative fractures, postoperative fractures, or stem subsidence. The mean change in Harris Hip Scores was significantly higher (P < .001) in the cTHA group (47.5 ± 4.9) than that in the cHA (38.9 ± 7.2) group at minimum 14-month follow-up. CONCLUSIONS: Despite potential advantages of cTHA or cHA for failed IT fractures, there were no differences in complications between either of the salvage procedures. Our analysis found a slight advantage in functional outcomes (Harris Hip Score) for cTHA at a minimum 14-month follow-up. Our study suggests that cTHA and cHA are both effective salvage procedures. Additional prospective studies are warranted to further delineate outcomes after salvage arthroplasty performed for failed IT fracture fixation.

The Role of Bariatric Surgery in the Obese Total Joint Arthroplasty Patient.

Although bariatric surgery is a proven means of weight loss and treatment of obesity-related comorbidities in morbidly obese patients, it is not yet clear how it affects outcomes after total joint arthroplasty in this high-risk patient population. This article explores the effects of obesity and bariatric surgery on osteoarthritis and total joint arthroplasty, and also discusses the financial and ethical implications of use of bariatric surgery for risk reduction before total joint arthroplasty.

Obesity: The Modifiable Risk Factor in Total Joint Arthroplasty.

Obesity is an epidemic in the health care system. Obesity poses several challenges and raises unique issues for the arthroplasty surgeon. Obese patients are at higher risk for infection and dislocation. Additionally, obese patients have poorer implant survivorship and functional scores postoperatively. Obesity is a modifiable risk factor and weight loss preoperatively should be strongly considered. Obese patients must be counseled so that they have realistic expectations after total joint arthroplasty.

Metal hypersensitivity in total hip and knee arthroplasty: Current concepts.

Metal hypersensitivity (MHS) is a rare complication of total joint arthroplasty that has been linked to prosthetic device failure when other potential causes have been ruled out. The purpose of this review was to conduct an analysis of existing literature in order to get a better understanding of the pathophysiology, presentation, diagnosis, and management of MHS. It has been described as a type IV hypersensitivity reaction to the metals comprising prosthetic implants, often nickel and cobalt-chromium. Patients suffering from this condition have reported periprosthetic joint pain and swelling as well as cutaneous, eczematous dermatitis. There is no standard for diagnosis MHS, but tests such as patch testing and lymphocyte transformation testing have demonstrated utility, among others. Treatment options that have demonstrated success include administration of steroids and revision surgery, in which the existing metal implant is replaced with one of less allergenic materials. Moreover, the definitive resolution of symptoms has most commonly required revision surgery with the use of different implants. However, more studies are needed in order to understand the complexity of this subject.

Rotating hinge prosthesis for complex revision total knee arthroplasty: A review of the literature.

INTRODUCTION: The rotating hinge prosthesis was originally used and designed as a primary total knee arthroplasty implant, but was hampered due to poor outcomes and catastrophic failures. Newer rotating hinge implants can be utilized in complex revision total knee arthroplasties when appropriately indicated, but their outcome data is very difficult to interpret due to the strict and varied indications for use and subsequently small number of procedures performed. The goal of this review is to evaluate the current evidence on large cohort, rotating hinge knee prostheses used in the revision setting, in order to provide a clearer understanding of the indications, outcomes and complications. METHODS: The PubMed database was utilized to search the available literature regarding "hinged knee," or "rotating hinge" devices. Exclusion criteria included papers focusing on primary arthroplasty, revision for oncologic issues, one-stage revision for infection or studies with less than fifty cases. RESULTS: Review of 115 abstracts after initial search, led to ten studies in the literature that met our inclusion and exclusion criteria. The data shows that rotating hinge knee implants have good survivorship ranging from 51% to 92.5% at 10 years post-operatively. Complication rates range from 9.2% to 63% with infection and aseptic loosening as the most common complications. CONCLUSION: Rotating hinge knee prostheses are most commonly indicated for infection, aseptic loosening, instability and bone loss in the literature. They have good outcome scores and survivorship, but continue to have high complication and revision rates. The implant is a good option when utilized appropriately for patients that are not candidates for less constrained devices.

Total Hip Arthroplasty in Paget's Disease A Review.

Paget's disease of the bone is a chronic osteopathy that leads to structural weakness, hypervascularity, and bone deformities. Rapid bone turnover in patients with Paget's disease may affect outcomes following total hip arthroplasty (THA). Most literature on THA in the setting of Paget's disease is limited to isolated case reports or case series documenting a single institution experience. By completing a comprehensive analysis of the available cases, this study aims to investigate the outcomes and complications of THA in patients with Paget's disease.

Does a non-stemmed constrained condylar prosthesis predispose to early failure of primary total knee arthroplasty?

PURPOSE: The use of unlinked constrained condylar components (CCK) has been extended to primary total knee arthroplasty (TKA); however, there is limited literature on its outcomes. The purpose of this retrospective cohort study was to assess clinical outcomes of one particular design of primary, non-stemmed, unlinked constrained TKA and to compare them with a control group of PS-TKA utilizing the same implant design. METHODS: The clinical and radiographic outcomes of 486-cemented, non-stemmed, primary TKA's performed by two surgeons at one institution using similar surgical algorithm, technique and prosthetic design were retrospectively reviewed. Primary TKA components were used in all knees; the only difference between groups was the type of polyethylene inserts used (CCK vs PS). Pre-operative deformity, knee society scores (KSS), range-of-motion (ROM), radiographic data and revision rates were compared. RESULTS: Both groups had comparable demographics, pre-operative coronal plane alignment, ROM and KSS. At a mean follow-up of 3.5 years, no difference was found in ROM, KSS, radiographic outcomes and revision rates. CONCLUSIONS: Cemented, primary, non-stemmed CCK-TKA offered comparable clinico-radiographic results to PS-TKA at short-term follow-up. Use of a semi-constrained insert without additional stems did not predispose to failure due to aseptic loosening with this implant design. Moreover, the rate of revision due to instability was lowered. LEVEL OF EVIDENCE: Retrospective cohort study, Level III.

Reducing blood loss in bilateral total knee arthroplasty with patient-specific instrumentation.

Patient-specific instrumentation (PSI) in total knee arthroplasty (TKA) has been introduced to obtain consistent alignment, prevent instrumentation of the medullary canal and improve operating room efficiency. This article compares simultaneous bilateral TKA performed with and without the use of PSI in terms of surgical time; blood loss and transfusion requirements; length-of-stay, early thromboembolic events and complication rates. There was a trend to reduced total blood loss (as measured by drop in hemoglobin values) and lower transfusion rate after surgery. Further research in the form of high quality randomized trials and cost-benefit analyses may help in further consolidation of these findings.

Femoral Revision Arthroplasty for Su Type 3 Supracondylar Periprosthetic Knee Fractures.

Periprosthetic distal femoral fractures can present significant reconstructive challenges when associated with poor bone stock, comminution, or component loosening. Revision arthroplasty with stemmed components or distal femoral replacement arthroplasty often becomes necessary. This retrospective study reviewed the results of femoral revision arthroplasty in 16 knees with acute, extreme distal (Su type 3), supracondylar periprosthetic fractures using cemented, midlevel constrained implants. The mean patient age was 71 years and mean follow-up was 5 years. All fractures united with mean Knee Society scores of 86 and 55, at the last follow-up. All patients returned to preinjury activity level. Complications included one valgus malunion with shortening and one reoperation for functional lateral instability. This treatment modality achieved reliable fracture union and return of function. Moreover, the final salvage option of distal femoral arthroplasty is preserved.