Matthew Hepinstall

Introduction: Longevity and success of total hip arthroplasty (THA) is largely dependent on component positioning. While use of robotic platforms can improve this positioning, published evidence on its clinical benefits is limited. Therefore, the aim of this study was to assess the clinical outcomes of THA with robotic surgical assistance. Materials and Methods: We conducted an analysis of robotic arm-assisted primary THAs performed by a single surgeon utilizing a posterior approach. A total of 99 patients (107 cases) who had a minimum two-year follow up were identified. Their mean age was 61 years (range, 33 to 84 years), and their mean body mass index was 30.5 kg/m2 (range, 18.5 to 49.1 kg/m2). There were 56% female patients and primary osteoarthritis was the principal hip diagnosis in 88.8%. Operative times, lengths of hospital stay, and discharge dispositions were recorded, along with any complications. Modified Harris Hip Scores (HHS) were calculated to quantify clinical outcom...

Introduction: Total hip arthroplasty (THA) in the setting of developmental dysplasia of the hip (DDH) presents more inherent complexities than routine primary THA for osteoarthritis. These include acetabular bone deficiency, limb length discrepancy (LLD), and abnormal femoral anteversion. Three-dimensional planning and robot-assisted (RA) bone preparation may simplify these complex procedures and make them more reproducible. The purpose of this study was to evaluate radiographic and clinical outcomes in a cohort of patients who had DDH and underwent an RA THA. Materials and Methods: We retrospectively analyzed 26 DDH patients who underwent RA THA by a single surgeon between 2013 and 2019. Their mean age was 54 years (range, 29 to 72 years) and mean follow up was approximately two years. Medical records were reviewed for demographics, clinical scores, Crowe classifications, and complications. There were thirteen Crowe I and seven Crowe II DDH hips, who were routinely managed with pri...

INTRODUCTION A variety of highly porous materials have been used to obtain biological acetabular fixation after total hip arthroplasty (THA). Due to their improved surface-coated properties, new highly porous titanium metal implants have shown potential to promote prosthesis osseointegration. Therefore, the purpose of this multicenter study was to evaluate: 1) overall acetabular cup survivorship; 2) postoperative complications; and 3) radiographic signs of loosening and radiolucencies in patients who received a new highly porous titanium metal cup. MATERIALS AND METHODS A total of 81 patients who underwent primary THA and received a new porous acetabular cup between May 16, 2013 and January 27, 2016 at three academic centers were included for analysis. There were 40 women (49%) and 41 men (51%) who had a mean age of 65 years (range, 38 to 95 years) and a mean body mass index (BMI) of 28 kg/m2 (range, 16 to 43 kg/m2). The minimum follow up time was two years and seven months (range, ...

Background Failure of cementless acetabular osseointegration is rare in total hip arthroplasty. Nevertheless, new fixation surfaces continue to be introduced. Novel implants may lack large diameter, constrained bearings, or dual mobility (DM) bearings to address instability. We compared clinical and radiographic outcomes for acetabular components with differing fixation surfaces and bearing options, focusing on the relationship between fixation surface and osseointegration and the relationship between bearing options and dislocation rate. Methods We retrospectively reviewed 463 total hip arthroplasties implanted with 3 different acetabular components between 2012 and 2016. Records were reviewed for demographics, clinical scores, and complications. Radiographs were examined for evidence of acetabular osteointegration. Analysis of variance and chi-square tests were used to compare cohorts. Results All cohorts had 100% survivorship free of acetabular fixation failure with no difference...

Background Guidelines support aspirin thromboprophylaxis for primary total hip and knee arthroplasty (THA and TKA) but supporting evidence has come from high volume centers and the practice remains controversial. Methods We studied 4562 Medicare patients who underwent elective primary THA (1736, 38.1%) or TKA (2826, 61.9%) at 9 diverse hospitals. Thirty-day claims data were combined with data from the health system’s electronic medical records to compare rates of venous thromboembolism (VTE) between patients who received prophylaxis with: (1) aspirin alone (47.3%), (2) a single, potent anticoagulant (29%), (3) antiplatelet agents other than aspirin or multiple anticoagulants (21.5%), or (4) low-dose subcutaneous unfractionated heparin or no anticoagulation (2.2%). Sub-analyses separately evaluating THA, TKA and cases from lower volume hospitals (n = 975) were performed. Results The 30-day VTE incidence was 0.6% (29/4562). VTE rates were equal in patients receiving aspirin and those ...

INTRODUCTION Imaging studies for preoperative planning of total hip arthroplasty (THA) are typically obtained by two-dimensional (2D) anteroposterior radiographs. However, CT imaging has proven to be a valuable tool that may be more accurate than standard radiographs. The purpose of this review was to report on the current literature to assess the utility of CT imaging for preoperative planning of THA. Specifically, we assessed its utility in the evaluation of: 1) hip arthritis; 2) femoral head osteonecrosis; 3) implant size prediction; 4) component alignment; 5) limb length evaluation; and 6) radiation exposure. MATERIALS AND METHODS A literature search was performed using search terms "computed tomography", "radiograph", "joint" "alignment", "hip," and "arthroplasty". Our initial search returned a total of 562 results. After applying our criteria, 26 studies were included. RESULTS CT scans were found to be more accurate t...

INTRODUCTION Longevity and success of total hip arthroplasty (THA) is largely dependent on component positioning. While use of robotic platforms can improve this positioning, published evidence on its clinical benefits is limited. Therefore, the aim of this study was to assess the clinical outcomes of THA with robotic surgical assistance. MATERIALS AND METHODS We conducted an analysis of robotic arm-assisted primary THAs performed by a single surgeon utilizing a posterior approach. A total of 99 patients (107 cases) who had a minimum two-year follow up were identified. Their mean age was 61 years (range, 33 to 84 years), and their mean body mass index was 30.5 kg/m2 (range, 18.5 to 49.1 kg/m2). There were 56% female patients and primary osteoarthritis was the principal hip diagnosis in 88.8%. Operative times, lengths of hospital stay, and discharge dispositions were recorded, along with any complications. Modified Harris Hip Scores (HHS) were calculated to quantify clinical outcomes...

The success of total knee arthroplasty depends on precise bone cuts to provide a neutrally aligned knee. Malalignment has been shown to lead to decreased satisfaction and higher rates of failure (1-4). Ritter et al. found that varus malalignment of the tibia was associated with a 10.6 times greater risk failure compared to neutrally aligned knees, while excessive femoral valgus greater than 8 degrees was associated with a 5.1 times increased risk (2). In the face of severe deformity or prior knee surgery, conventional total knee arthroplasty (TKA) instrumentation may not be sufficient to provide consistent, accurate results. Along with severe deformity, cases unable to utilize intramedullary instrumentation or those with significant bone loss may require the preoperative planning and precise bone cuts that are associated with roboticassisted total knee arthroplasty. Marchand et al. found that the robotic software was able to predict implants within one size for 98% of cases. (5). Ro...

Back pain may both decrease patient satisfaction after TKA and confound outcome assessment in satisfied patients. Our primary objective was to determine whether preoperative back pain is associated with differences in postoperative patient-reported outcome measures (PROMs). We retrospectively reviewed 234 primary TKA patients who completed PROMs preoperatively and 12 weeks postoperatively, which included a back pain questionnaire, the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) and the Forgotten Joint Score-12 (FJS-12). Cohorts were defined based on the severity of preoperative back pain (none, mild, moderate and severe) and compared. Demographics were compared using ANOVA and Chi-square analysis. Univariate ANCOVA analysis was utilized to compare PROMs while accounting for significant demographic differences. Both preoperative KOOS JR scores (none: 47.90, mild: 47.61, moderate: 44.61 and severe: 38.70; p = 0.013) and 12-week postoperative KOOS JR scores (none: 61.24, mild: 64.94, moderate: 57.48 and severe: 57.01; p = 0.012) had a statistically significant inverse relationship with regard to the intensity of preoperative back pain. Although FJS-12 scores at the 12-week postoperative period trended lower with increasing levels of preoperative back pain (p = 0.362), it did not reach statistical significance. Patients who reported severe back pain preoperatively achieved the largest delta improvement from baseline compared to those with lesser pain intensity (p = 0.003). Patients who had a 2-grade improvement in their back pain achieved significantly higher KOOS JR scores 12 weeks postoperatively compared to patients with either 1-grade or no improvement (63.53 vs. 55.98; p = 0.042). Both preoperative (47.99 vs. 41.11; p = 0.003) and 12-week postoperative (64.06 vs. 55.73; p < 0.001) KOOS JR scores were statistically higher for those who reported mild or no back pain pre-and postoperatively than those who reported moderate or severe back pain pre-and postoperatively. Knee pain and back pain both exert negative effects on outcome instruments designed to measure pain and function. Although mean improvement from pre- to postoperative KOOS JR scores for patients with severe pre-existing back pain was higher than their counterparts, this statistical difference is likely not clinically significant. This implies that all patients may experience similar benefits from TKA despite the presence or absence of back pain. Attempts to measure TKA outcomes using PROMs should seek to control for lumbago and other sources of body pain. Level of Evidence IIIRetrospective Cohort Study

Aims The COVID-19 pandemic led to a swift adoption of telehealth in orthopaedic surgery. This study aimed to analyze the satisfaction of patients and surgeons with the rapid expansion of telehealth at this time within the division of adult reconstructive surgery at a major urban academic tertiary hospital. Methods A total of 334 patients underging arthroplasty of the hip or knee who completed a telemedicine visit between 30 March and 30 April 2020 were sent a 14-question survey, scored on a five-point Likert scale. Eight adult reconstructive surgeons who used telemedicine during this time were sent a separate 14-question survey at the end of the study period. Factors influencing patient satisfaction were determined using univariate and multivariate ordinal logistic regression modelling. Results A total of 68 patients (20.4%) and 100% of the surgeons completed the surveys. Patients were “Satisfied” with their telemedicine visits (4.10/5.00 (SD 0.98)) and 19 (27.9%) would prefer telem...

BACKGROUND Registry data suggest increasing rates of early revisions after total hip arthroplasty (THA). We sought to analyze modes of failure over time after index THA to identify risk factors for early revision. METHODS We identified 208 aseptic femoral revision THAs performed between February 2011 and July 2019 using an institutional database. We compared demographics, diagnoses, complications, and resource utilization between aseptic femoral revision THA occurring within 90 days (early), 91 days to 2 years (mid), and greater than 2 years (late) after index arthroplasty. RESULTS Early revisions were 33% of revisions at our institution in the time period analyzed. Periprosthetic fractures were 81% of early, 27% of mid, and 21% of late femoral revisions (P < .01). Women were more likely to have early revisions than men (75% vs 53% of mid and 48% of late revisions; P < .01). Patients who had early revisions were older (67.97 ± 10.06) at the time of primary surgery than those who had mid and late revisions (64.41 ± 12.10 and 57.63 ± 12.52, respectively, P < .01). Index implants were uncemented in 99% of early, 96% of mid, and 64% of late revisions (P < .01). Early revisions had longer postoperative length of stay (4.4 ± 3.3) than mid and late revisions (3.0 ± 2.2 and 3.7 ± 2.1, respectively, P = .02). In addition, 58% of early revisions were discharged to an inpatient facility compared with 36% of mid and 41% of late revisions (P = .03). CONCLUSION Early aseptic femoral revisions largely occur in older women with uncemented primary implants and primarily due to periprosthetic fractures. Reducing the incidence of periprosthetic fractures is critical to decreasing the large health care utilization of early revisions.

Introduction: Approximately half of dislocating total hip arthroplasties (THAs) demonstrate acetabular component position within traditional safe zones. It is unclear if postoperative functional acetabular position can be reliably improved by considering preoperative pelvic tilt. We investigated whether standing cup position targets could be more accurately achieved by considering preoperative standing pelvic tilt in addition to bone landmarks when planning for robot-assisted THA. Methods: We reviewed 146 THAs performed by a single surgeon using computed tomography-based 3-dimensional planning and robotic technology to guide acetabular reaming and component insertion. Planning for 73 consecutive cases started at 40° of inclination and 22° of anteversion relative to the supine functional plane and was adjusted to better match native hip anatomy. Planning for the next 73 cases was modified to consider standing pelvic position based on standing preoperative radiographs. We compared gro...

BACKGROUND Dual mobility (DM) total hip arthroplasty (THA) implants have been advocated for patients at risk for impingement due to abnormal spinopelvic mobility. Impingement against cobalt-chromium acetabular bearings, however, can result in notching of titanium femoral stems. This study investigated the incidence of femoral stem notching associated with DM implants and sought to identify risk factors. METHODS A multicenter retrospective study reviewed 256 modular and 32 monoblock DM components with minimum 1-year clinical and radiographic follow-up, including 112 revisions, 4 conversion THAs, and 172 primary THAs. Radiographs were inspected for evidence of femoral notching and to calculate acetabular inclination and anteversion. Revisions and dislocations were recorded. RESULTS Ten cases of femoral notching were discovered (3.5%), all associated with modular cylindrospheric cobalt-chromium DM implants (P = .049). Notches were first observed radiographically at mean 1.3 years after surgery (range 0.5-2.7 years). Notch location was anterior (20%), superior (60%), or posterior (20%) on the prosthetic femoral neck. Notch depth ranged from 1.7% to 20% of the prosthetic neck diameter. Eight cases with notching had lumbar pathology that can affect spinopelvic mobility. None of these notches resulted in stem fracture, at mean 2.7-year follow-up (range 1-7.6 years). There were no dislocations or revisions in patients with notching. CONCLUSION Femoral notching was identified in 3.5% of DM cases, slightly surpassing the dislocation rate in a cohort selected for risk of impingement and instability. Although these cases of notching have not resulted in catastrophic failures thus far, further study of clinical sequelae is warranted. Component position, spinopelvic mobility, and implant design may influence risk.

Haptic robotic-arm-assisted total knee arthroplasty (RATKA) seeks to leverage three-dimensional planning, intraoperative assessment of ligament laxity, and guided bone preparation to establish and achieve patient-specific targets for implant position. We sought to compare (1) operative details, (2) knee alignment, (3) recovery of knee function, and (4) complications during adoption of this technique to our experience with manual TKA. We compared 120 RATKAs performed between December 2016 and July 2018 to 120 consecutive manual TKAs performed between May 2015 and January 2017. Operative details, lengths of stay (LOS), and discharge dispositions were collected. Tibiofemoral angles, Knee Society Scores (KSS), and ranges of motion were assessed until 3 months postoperatively. Manipulations under anesthesia, complications, and reoperations were tabulated. Mean operative times were 22 minutes longer in RATKA (p 

Medial unicondylar knee arthroplasty (UKA) is a widely accepted treatment option for patients with bone-on-bone medial tibiofemoral compartment osteoarthritis, intact cruciate and collateral ligaments, and mild deformity. Performed well in properly indicated patients, UKA results in a faster recovery, more-normal kinematics, and a lower incidence of arthrofibrosis and other early complications compared to TKA [16]. However, UKAs are more likely to undergo revision than are TKAs according to some registry studies [3, 16], highlighting the need to identify patients at high risk for early revision surgery sowe can inform them about this risk, and perhaps suggest alternative treatments. Kozinn and Scott [10] suggested restricting UKA indications based on age, weight, activity, presence of chondrocalcinosis or inflammatory arthritis, patterns of cartilage loss, and preoperative ROM. They also proposed that varus deformity be no greater than 10° for medial UKA and passively correctable to neutral at the time of surgery after removal of osteophyte [10]. Although primarily a statement of expert opinion, this pioneering work continues to influence thinking about appropriate indications and contraindications for UKA. Researchers from the Oxford group [6] have challenged these narrow indications, reporting comparable Oxford Knee Scores, improved Tegner Activity Scores and Knee Society Function scores, and fewer patients with poor Knee Society Objective scores when wider (though clearly defined) indications are followed. Registry data show UKAs have the lowest rate of reoperations when performed by surgeons with high UKA utilization relative to TKA [11], suggesting that broad indications may both allow surgeons to develop greater technical proficiency and offer the relative benefits of UKA to a larger percentage of patients with knee osteoarthritis (OA). These broadened indications remain controversial, with other investigators reporting higher early reoperation rates when traditional criteria are not met, such as when UKA is performed on patients with morbid obesity [14]. While accepted indications for medial UKA have emphasized the importance of any varus deformity being small and correctable, published evidence shows overcorrection into valgus is a major risk factor for progression of lateral compartment arthritis [7]. The authors of the current study [9] used objective radiographic criteria to identify patients at risk for overcorrection at the time ofmedialUKAusing a specific manual technique and instrumentation. Knees correctable near neutral alignment on full extension valgus stress radiographs were at increased risk for overcorrection. Greater magnitudes of medial meniscal extrusion on MRI were associated with greater magnitudes of correction at surgery. Knees with both findings were at highest risk for overcorrection. These This CORR Insights is a commentary on the article “Valgus Correctability and Meniscal Extrusion Were Associated With Alignment After Unicompartmental Knee Arthroplasty” by Ishibashi and colleagues available at: DOI: 10.1097/CORR.0000000000001260. One of the authors (MSH) certifies, or a member of his or her immediate family, has received or may receive payments or benefits, during the study period, an amount of USD (10,000 to USD 100,000), from Stryker, Kalamazoo, MI, USA). The opinions expressed are those of the writer, and do not reflect the opinion or policy of CORR or The Association of Bone and Joint Surgeons. M. S. Hepinstall MD (✉), NYU Langone Orthopedic Hospital, 301 East 17 Street, Suite 1402, New York, NY 10003, USA, Email: hepinstallm@gmail.com

Introduction:Robotic-arm assisted (RAA) total knee arthroplasty (TKA) has been shown to potentially have certain pre- and intra-operative advantages over manual techniques. Although there are many studies on the alignment advantages when using the robotic-arm assisted (RAA) system for total knee arthroplasty (TKA), there have been questions regarding patient-reported outcomes. Therefore, the purpose of this study was to use this index to compare: 1) total; 2) physical function; and 3) pain scores for manual vs. RAA patients.Methods:We compared 53 consecutive robotic-arm assisted to 53 consecutive manual TKAs. No differences in pre-operative scores were found between the cohorts. Patients were administered a modified WOMAC satisfaction survey pre-operatively, and at 1-year post-operatively. Univariate analyses and multivariate models with stepwise backward linear regression were utilized to evaluate the associations between outcome scores and surgical technique, age, sex, as well as ...

Introduction:There is a lack of data concerning the use of the robotic device for patients with other potentially complex surgical factors. Therefore, the purpose of this series was to present cases in which the robotic-arm assisted TKA (RATKA) application was used in the setting of extra-articular deformities to educate the surgeon community on this potentially useful method to address these complex cases.Methods:Three cases of patients who underwent RATKA in the setting of pre-operative extra-articular deformities were identified. One had femoral and tibial fracture malunion, another had proximal tibial fracture nonunion, and another with a healed tibial plateau fracture. Patient clinical histories, intra-operative surgical techniques, and post-operative outcomes were obtained. Specific focus was placed on the surgical management of the patient’s pre-existing deformity.Results:The robotic software was able to appropriately consider the extra-articular deformity in the pre-operativ...

Introduction:Robotic-arm assisted surgery allows for the execution of well-aligned knee arthroplasty regardless of pre-existing deformity. This case series is presented to show the utility of robotic-arm assisted TKA in achieving well-balanced, well-aligned results in a variety of challenging scenarios.Methods:We present seven challenging cases of robotic-arm assisted total knee arthroplasty. There were two conversion TKAs following a previous surgery. One case featured a previous tibial plateau fracture treated with a plate and screws construct while another featured a prior femoral nail with significant bony overgrowth. Five cases of severe deformity were also identified, with one tibial nonunion, two valgus knees and one patient with two varus knees due psoriatic arthritis treated with staged bilateral TKAs. Patient clinical history, physical examinations, intraoperative surgical techniques and postoperative courses were recorded.Results:All cases were able to utilize effective p...

The potential added costs of managing fibromyalgia patients after total knee arthroplasty (TKA) have not been assessed. Therefore, the purpose of this study was to perform a cost analysis of fibromyalgia versus nonfibromyalgia patients who underwent TKA. Specifically, we evaluated the following episodes of care: (1) readmission rates, (2) total costs, (3) total reimbursements, and (4) net losses for surgical and medical complications. Patients who underwent TKAs between 2005 and 2014 from the Medicare Standard Analytical Files of the PearlDiver supercomputer were propensity score matched by patients with and without fibromyalgia in a 1:1 ratio based on age, sex, and the Charlson Comorbidity Index, yielding a total of 305,510 patients distributed equally between the cohorts for analysis. Odds ratios (ORs), 95% confidence intervals (CIs), and p-values were calculated. Mean costs, total costs, and total reimbursements were assessed as along with total net losses, which were defined as ...

BACKGROUND Prompt identification and treatment of wound complications is essential after joint arthroplasty, but emergency department and office visits for urgent evaluation of normal incisions are a source of unnecessary cost. The purpose of this study is to evaluate the use of an online image messaging platform for remote monitoring of surgical incision sites. METHODS We conducted a retrospective review of 1434 hip and knee arthroplasty patients who registered for an online platform in the perioperative period. We reviewed images sent by patients to evaluate potential wound abnormalities. Medical records were reviewed to determine whether assessments based on wound photographs corresponded with subsequent in-person findings and ultimate disposition. RESULTS Four hundred thirty patients (42%) sent at least one text or image message to their provider. Elimination of redundant images resulted in 104 image encounters, with 76 discrete encounters in 41 patients related to the surgical wound. Most showed normal wound appearance; patients were reassured and urgent visits were avoided. At scheduled in-person follow-up, none of these patients demonstrated unrecognized wound complications. Seventeen image encounters in 7 patients showed possible wound abnormalities. These prompted in-person follow-up on average less than 1 day later for 4 issues deemed urgent (2 patients received surgical treatment) and 5 days later for issues deemed nonurgent. Photos were also used to monitor abnormal wounds over time and to send information unrelated to wounds. CONCLUSION Utilization of an online physician-patient messaging platform can prevent unnecessary visits for normal appearing wounds, while facilitating rapid in-person treatment of wound complications.

BACKGROUND The purpose of this study is to track the 30-day postoperative annual rates and trends of (1) overall, (2) deep, and (3) superficial surgical site infections (SSIs) following total hip arthroplasty (THA) using a large nationwide database. METHODS The National Surgical Quality Improvement Program database was queried for all THA cases performed between 2012 and 2016. After an overall 5-year correlation and trends analysis, univariate analysis was performed to compare the most recent year, 2016, with the preceding 4 years. Correlation coefficients and chi-squared tests were used to determine correlation and statistical significance. RESULTS The lowest incidence of SSIs was in the most recent year, 2016 (0.81%), while the greatest incidence was in the earliest year, 2012 (1.12%), marking a 31% decrease (P < .01). The lowest rate was in the most recent year, 2016 (0.23%), marking a 26% decrease from 2012. The lowest superficial SSI incidence occurred in the most recent year, 2016 (0.58%), while greatest incidence was in 2012 (0.83%), marking a 31% decrease over time (P < .05). There was an inverse correlation among overall, deep, and superficial SSI rates with operative year. CONCLUSION The findings from this study suggest a decreasing trend in SSIs within 30 days following THA. Furthermore, deep SSIs, which can pose substantial threats to implant survivorship, have also decreased throughout the years. These results highlight that potentially through improved medical and surgical techniques, we are winning the fight against short-term infections, but that more can still be done.

Although there are many studies on the alignment advantages when using the robotic arm–assisted (RAA) system for total knee arthroplasty (TKA), there have been questions regarding patient-reported outcomes. Therefore, the purpose of this study was to use this index to compare: (1) total, (2) physical function, and (3) pain scores for manual versus RAA patients. We compared 53 consecutive RAA to 53 consecutive manual TKAs. No differences in preoperative scores were found between the cohorts. Patients were administered a modified Western Ontario and McMaster Universities Osteoarthritis Index satisfaction survey preoperatively and at 1-year postoperatively. The results were broken down to: (1) total, (2) physical function, and (3) pain scores. Univariate analysis with independent samples t-tests was used to compare 1-year postoperative scores. Multivariate models with stepwise backward linear regression were utilized to evaluate the associations between scores and surgical technique, a...

We report the failure of a routine arthrotomy repair following knee arthroplasty. Five additional cases of arthrotomy failure occurred within a 14-month period during which a specific unidirectional knotless barbed suture device had been used for arthrotomy closure. Additional study on larger cohorts may be useful to understand the effectiveness of barbed suture for arthrotomy closure in knee arthroplasty.

Symptomatic instability following total knee arthroplasty (TKA) is a leading cause of early failure. Most reports recommend component revision as the preferred treatment because of poor outcomes and high failure rates with isolated tibial polyethylene insert exchange (ITPIE). However, these ideas have not been tested in modern implant systems that allow insert constraint to be increased. We retrospectively reviewed 90 consecutive patients with minimum 2-year (mean 3.7 years) follow-up who underwent revision TKA for instability at a single institution. Mean age was 62.0 years (range, 41 to 83 years), and 73% of patients were women. Forty percent of patients were treated with ITPIE when standardized preoperative and intraoperative criteria were met; 60% underwent revision of one or both components when these criteria were not met. Patients experienced significant improvements in Knee Society (KS) knee (48.4 to 82.6; P < .001) and function (49.0 to 81.0; P < .001) scores. There w...

We evaluated which treatment decisions in the management of displaced femoral neck fractures (FNFs) may associate with measures of resource utilization relevant to a value-based episode-of-care model. A total of 1139 FNFs treated with hip arthroplasty at 7 hospitals were retrospectively reviewed. Treatment choices were procedure (hemiarthroplasty vs total hip arthroplasty [THA]), surgeon training status, admitting service, and time to surgery. Dependent variables were length of stay, discharge disposition, 30-day readmission, and in-hospital mortality. Variation across hospitals was evaluated with analysis of variance and chi-square tests. Treatment choices were evaluated for the dependent variables of interest with univariable and multivariable regression. There was significant variation between hospitals regarding proportion of cases treated with THA (range = 3.0%-73.2%, P < .001), proportion treated by arthroplasty fellowship-trained surgeons (range = 0%-74.9%, P < .001), p...

There is mounting evidence that treatment of periprosthetic joint infection of the knee with an antibiotic cement spacer (ACS) may increase risk for acute kidney injury (AKI). We sought to determine the incidence, as well as potential risk factors, of in-hospital AKI in this cohort. We retrospectively identified 75 patients that received either a static or articulating ACS at a single institution. In-hospital AKI was defined by a more than 50% rise in serum creatinine from preoperative baseline to at least 1.4 mg/dL. Our secondary outcome was percent change in creatinine from preoperative to peak postoperative value. Variables were analyzed for the outcome of AKI with univariate logistic regression. A final multivariate model for percent change in creatinine was formed while controlling for age, gender, body mass index, and baseline creatinine. The incidence of AKI was 14.6%, occurring at a mean of 6.3 days (2-8 days). A lower preoperative hemoglobin (odds ratio = 1.82, P = .015) si...

Periprosthetic fractures (PPFXs) are becoming increasingly common following total hip arthroplasty (THA) and total knee arthroplasty (TKA). Patients sustaining PPFXs face considerable perioperative morbidity, with relatively increased rates of surgical site infection. We sought to evaluate the efficacy of closed-incision negative-pressure wound therapy (ciNPT) in decreasing perioperative wound complications following lower extremity periprosthetic fracture surgery. We performed a retrospective review of 69 consecutive patients who underwent surgery to address lower extremity periprosthetic fractures around hip or knee implants performed over a 6.5-year period. The population was divided into two groups based on the surgical dressing used at the conclusion of the procedure: (1) a sterile, antimicrobial hydrofiber dressing, or (2) ciNPT. There were no baseline demographic differences between the two groups. Rates of wound complications, surgical site infection, and reoperation related...

Background: The purposes of this study were (1) to evaluate standardized radiographic parameters in a population of patients who developed stiffness after primary total knee arthroplasty (TKA), and (2) to compare those to a matched control population. Methods: A retrospective review was performed to identify patients who required revision for stiffness after primary TKA. Patients with history of TKA revision or infection, as well as, those treated with isolated polyethylene exchange were excluded. Study patients were matched 1:1 with controls based on age, sex, body mass index (BMI). Radiographic measurements were performed by two blinded independent observers. Results: A total of 44 patients met the inclusion criteria. Thirty-one (70%) were females. Mean BMI was 33 kg/m2 (19-58). Univariate odds ratios showed significance for patella baja (5.776; 0.025), increased anterior condylar offset ratio (ACO) (15.265; 0.000), increased anterior implant-cortex gap (5.067; 0.038), and increased percentage of patellar displacement (PPD) (6.476; 0.016). Multivariate regression analysis showed significance for ACO (18.307; 0.001) and PPD (9.338; 0.024). No significance was observed with respect to component alignment in the coronal or sagittal planes, posterior condylar offset ratio, patellar tilt, presence of heterotopic ossification, or posterior osteophyte formation. Intraclass correlation coefficients (ICCs) ranged from good to excellent (>0.8) for all measurements performed. Conclusions: The restoration of the joint line and avoiding overstuffing the patellofemoral compartment are fundamental in preventing the development of postoperative stiffness. Poor mechanics of the patellofemoral compartment are significantly associated with the development of stiffness after primary TKA.

Periprosthetic femoral fractures, which are likely to increase as the population ages and total hip arthroplasty becomes more prevalent, can be effectively managed by restoring femoral length via preoperative planning and surgical execution using a cementless, tapered, fluted stem. Template the contralateral, uninjured side. Identify the ideal COR on the injured side and template the femoral stem. Use stem templates to establish a reference point on the reamer for use intraoperatively, and identify the distance from that point to an identifiable distal landmark. We report on 14 (12 Vancouver type-B2 and 2 Vancouver type-B3) periprosthetic femoral fractures treated with the described method.

There has been a great increase in the use of navigation technology in joint arthroplasty. In most types of navigation-assisted surgery, several temporary navigation pins are placed in the patient. Goals of this study are (1) to identify complications and (2) risk factors associated with placement of these pins. This is a retrospective cohort study of all navigation-assisted hip and knee arthroplasty performed a single institution over a 3-year period. Records were reviewed and outcome measures were tabulated in a database. Complications included in the database were pin site infection, deep prosthetic joint infection, neurologic injury, vascular injury, and fracture through a pin site. A total of 3136 pin sites in 839 patients were included in the study. Five pin site complications were reported with a complication rate of 0.16% per pin site and 0.60% per patient. The complications-per-procedure were slightly higher for unicondylar knee arthroplasty (0.64%) compared with patellofem...

Haptic robotic-arm assisted technology improves accuracy in unicompartmental knee replacement through utilizing a preoperative 3-D plan, optical navigation for real-time intraoperative feedback on soft tissue laxity, and robotic arm for precise bone preparation. This technology became clinically available for total knee arthroplasty (TKA) in 2016. We present outcomes from the early adoption of this technique.A retrospective chart review compared data from the first 120 robotic-arm assisted TKAs performed December 2016 through July 2018 to the last 120 manually instrumented TKAs performed May 2015 to December 2016, prior to robotic technology adoption.Robotic surgery was associated with significantly increased anesthesia (212 vs 187 mins, p < 0.01) and operative (135 vs 112 minutes, p < 0.01) time. The robotic group had a lower hospital length-of-stay (2.7 vs. 3.4 days, p < 0.001). Discharge to home was not statistically different between robotic and manual groups (89% vs. 8...

Modern total hip replacement is typically effective and durable, but early failures do occur. Component position influences functional outcome, durability, and risk of complications. Surgical robotics provides the detail-oriented surgeon with a robust tool to optimize the accuracy and precision of total hip arthroplasty, with the potential to minimize risk of mechanical failure. This article describes efficient workflows for using surgical robotics to optimize surgical precision without increasing surgical complexity.

Component malalignment can be associated with pain following total knee replacement (TKR). Using MRI, we reviewed 50 patients with painful TKRs and compared them with a group of 16 asymptomatic controls to determine the feasibility of using MRI in evaluating the rotational alignment of the components. Using the additional soft-tissue detail provided by this modality, we also evaluated the extent of synovitis within these two groups. Angular measurements were based on the femoral transepicondylar axis and tibial tubercle. Between two observers, there was very high interobserver agreement in the measurements of all values. Patients with painful TKRs demonstrated statistically significant relative internal rotation of the femoral component (p = 0.030). There was relative internal rotation of the tibial to femoral component and combined excessive internal rotation of the components in symptomatic knees, although these results were significant only with one of the observers (p = 0.031). There was a statistically significant association between the presence and severity of synovitis and painful TKR (p < 0.001). MRI is an effective modality in evaluating component rotational alignment.

ABSTRACT Purpose of review: The aim of this article is to review the principles of alignment in total knee arthroplasty and the surgical landmarks available for optimizing component position, and to summarize and interpret recently published data on these subjects to aid the orthopedic surgeon in utilizing best practices based on current evidence. Recent findings: One focus of recent investigations in total knee arthroplasty has been a critical appraisal of surgical landmarks used to determine prosthetic alignment, with the aim of achieving more reproducible results with standard instruments. A second focus has been a comparison of computer navigation systems to traditional guides and jigs. With regard to coronal and sagittal alignment, navigation has decreased the frequency of ‘outliers’, whereas improvement in rotational alignment has not been consistently demonstrated. Navigation has not been shown to improve clinical outcomes in the short term. The cost, learning curve, and increased surgical times currently associated with navigation continue to limit its widespread adoption. Summary: The principles of alignment in total knee arthroplasty remain unchanged. Proper alignment can be reproducibly achieved by recognition of specific anatomic landmarks and proper use of traditional instrumentation; new data suggest, however, that navigation may help surgeons to minimize the risk of coronal malalignment.