Effects of Abaloparatide on Bone Mineral Density in Proximal Femoral Regions Corresponding to Arthroplasty Gruen Zones: A Study of Postmenopausal Women with Osteoporosis.

BACKGROUND: Low hip bone mineral density (BMD) in patients who undergo total hip arthroplasty (THA) increases the risk of periprosthetic fractures, implant instability, and other complications. Recently, emphasis has been placed on bone health optimization: treating low BMD prior to a planned orthopaedic implant procedure in an effort to normalize BMD and reduce the potential risk of future complications. Abaloparatide is a U.S. Food and Drug Administration-approved osteoanabolic agent for men and postmenopausal women with osteoporosis and a candidate drug for bone health optimization that, in addition to benefits at the spine, increases hip BMD and reduces nonvertebral fracture risk. We hypothesized that abaloparatide would improve BMD in proximal femoral regions surrounding a virtual THA stem. METHODS: This post hoc analysis obtained dual x-ray absorptiometry (DXA) hip scans from 500 randomly selected postmenopausal women with osteoporosis from the Phase-3 Abaloparatide Comparator Trial in Vertebral Endpoints (ACTIVE, NCT01343004) study after 0, 6, and 18 months of abaloparatide (250 patients) or placebo (250 patients). Hip DXA scans underwent 3-dimensional (3D) modeling via 3D-Shaper, followed by virtual resection of the proximal femur and simulated placement of a tapered, flat-wedge hip stem that guided delineation of the Gruen zones that were fully (zones 1 and 7) or largely (zones 2 and 6) captured in the scanning region. Integral, cortical, and trabecular volumetric BMD, cortical thickness, and cortical surface BMD (the product of cortical volumetric BMD and cortical thickness) were determined for each zone. RESULTS: Compared with placebo, the abaloparatide group showed greater increases in integral volumetric BMD in all zones at months 6 and 18; cortical surface BMD in zones 1, 6, and 7 at month 6; cortical thickness, cortical volumetric BMD, and cortical surface BMD in all zones at month 18; and trabecular volumetric BMD in zones 1 and 7 at months 6 and 18. CONCLUSIONS: Abaloparatide increases BMD in proximal femoral regions that interact with and support femoral stems, suggesting that abaloparatide may have value for preoperative or potentially perioperative bone health optimization in patients with osteoporosis undergoing THA. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

AAHKS Surgical Techniques & Technologies Award: Inferior Screw Fixation Decreases Acetabular Component Failure Following Revision Total Hip Arthroplasty.

BACKGROUND: Adjunctive screw fixation has been shown to be reliable in achieving acetabular component stability in revision total hip arthroplasty (THA). The purpose of this study was to assess the effect of inferior screw placement on acetabular component failure following revision THA. We hypothesized that inferior screw fixation would decrease acetabular failure rates. METHODS: We reviewed 250 patients who had Paprosky Type II or III defects who underwent acetabular revision between 2001 and 2021 across three institutions. Demographic factors, the number of screws, location of screw placement (superior versus inferior), use of augments and/or cup-cage constructs, Paprosky classification, and presence of discontinuity were documented. Multivariate regression was performed to identify the independent effect of inferior screw fixation on the primary outcome of aseptic rerevision of the acetabular component. RESULTS: At a mean follow-up of 53.4 months (range, 12 to 261), 16 patients (6.4%) required re-revision for acetabular loosening. There were 140 patients (56.0%) who had inferior screw fixation, all of whom did not have neurovascular complications during screw placement. Patients who had inferior screws had a lower rate of acetabular rerevision than those who only had superior screw fixation (2.1 versus 11.8%, P = .0030). Multivariate regression demonstrates that inferior screw fixation decreased the likelihood of rerevision for acetabular loosening when compared to superior screw fixation alone (odds ratio: 0.1, confidence interval: 0.03 to 0.5; P = .0071). No other risk factors were identified. CONCLUSIONS: Inferior screw fixation is a safe and reliable technique to reduce acetabular component failure following revision THA in cases of severe acetabular bone loss.

How modular porous metal augments have changed the management of acetabular bone loss at primary or revision total hip arthroplasty.

The advent of modular porous metal augments has ushered in a new form of treatment for acetabular bone loss. The function of an augment can be seen as reducing the size of a defect or reconstituting the anterosuperior/posteroinferior columns and/or allowing supplementary fixation. Depending on the function of the augment, the surgeon can decide on the sequence of introduction of the hemispherical shell, before or after the augment. Augments should always, however, be used with cement to form a unit with the acetabular component. Given their versatility, augments also allow the use of a hemispherical shell in a position that restores the centre of rotation and biomechanics of the hip. Progressive shedding or the appearance of metal debris is a particular finding with augments and, with other radiological signs of failure, should be recognized on serial radiographs. Mid- to long-term outcomes in studies reporting the use of augments with hemispherical shells in revision total hip arthroplasty have shown rates of survival of > 90%. However, a higher risk of failure has been reported when augments have been used for patients with chronic pelvic discontinuity.

Evaluation and Management of Acetabular Bone Loss in Revision Total Hip Arthroplasty: A 10-year Update.

Acetabular bone loss continues to be one of the most complex and challenging scenarios facing the orthopaedic surgeon. Preoperative planning and classification systems essentially have remained the same, with the Paprosky classification still being the most commonly used. Careful radiological assessment with well-defined criteria can accurately diagnose acetabular bone loss patterns with an associated chronic pelvic discontinuity before surgery. The use of cemented reconstruction techniques has declined, and contemporary practice trends have involved the increasing use of highly porous hemispherical shells in conjunction with modular porous metal augments, which can successfully treat most acetabular revisions. Noncemented treatment options for the management of acetabular bone loss during revision include conventional porous/modular highly porous hemispherical implants, nonmodular highly porous implants with cementable acetabular liners, cup-cage reconstruction, oblong cups, and triflange reconstruction. These options can be combined with modular porous metal augments, structural allografts, impaction grafting, or reconstruction cages. Acetabular distraction is a newer technique for chronic pelvic discontinuity, which is used in conjunction with off-the-shelf revision acetabular shells and modular porous metal augments. This review is an update over the past decade, highlighting studies with mid to long-term follow-up, and presents the advantages, disadvantages, and principles associated with each of the most commonly used reconstructive techniques.

Increasing the Volume of Outpatient Total Joint Arthroplasty Procedures: An Evaluation of a Novel Rapid Recovery Pathway Program Within an Academic Medical Center.

Background: There has been a national trend toward shifting joint arthroplasty procedures to the outpatient setting. These cases are often performed in freestanding ambulatory surgery centers (ASCs), which are often not accessible to surgeons within academic practices. Purposes: We sought to investigate a novel rapid recovery program used to transition arthroplasty patients to an outpatient-based care system within an academic medical center. Methods: All patients undergoing hip or knee arthroplasty between November 2019 and April 2021 were retrospectively evaluated for their eligibility for a rapid recovery pathway through the Extended Stay Unit (ESU) based on clinical and social criteria. Once admitted, patients were evaluated for whether they were discharged from the unit or if hospital admission was necessary. Results: Out of the 444 patients deemed candidates for the rapid recovery program, 188 patients were admitted to the ESU (42.3%); 18 (9.6%) required inpatient hospital admission, with the majority of these due to failing physical therapy (16; 88.9%). Of the ESU patients who were successfully discharged home, 55 (32.4%) were discharged on postoperative day (POD) 0 and 115 (67.6%) on POD 1 (<23 hours). Conclusion: As total joint arthroplasties shift toward the outpatient setting, surgeons in academic institutions must employ strategies to increase their volume of patient candidates for outpatient procedures. Our retrospective study of prospectively collected data suggests the feasibility of creating a separate rapid recovery unit within the hospital that can be an effective method by which to eventually transition to the ASC setting.

Acetabular Distraction Technique: A Multicenter Study With a Minimum 2-Year Radiographic Follow-Up.

BACKGROUND: Chronic pelvic discontinuity is a challenge during revision total hip arthroplasty due to the loss of structural continuity of the superior and inferior aspects of the acetabulum from severe acetabular bone loss. Acetabular distraction provides an alternative surgical treatment by stabilizing the acetabular component through elastic recoil of the pelvis, which may be supplemented with modular porous augments for addressing major acetabular defects. This study reports 2-year radiographic findings following acetabular distraction for the treatment of chronic pelvic discontinuity. METHODS: Patients undergoing acetabular distraction performed by 5 surgeons from 2002 to 2021 were identified across 5 institutions. Demographic, surgical, and postoperative outcomes, including radiographic component stability, were recorded. There were 53 of 91 (58.2%) patients (5 deceased, 33 lost to follow-up) consisting of 4 Paprosky IIC (7.5%), 8 Paprosky IIIA (15.1%), and 41 Paprosky IIIB (77.4%) defects included, with a mean follow-up time of 4.8 years (range, 2 to 13.5). Modular porous augments were used in 33 (62.3%) cases. Failure was defined as a subsequent revision of the acetabular construct. RESULTS: Among the 13 (24.5%) patients who returned to the operating room, 6 (46.2%) had a prior history of revision total hip arthroplasty before undergoing acetabular distraction. Only 5 (9.4%) patients underwent acetabular revision following acetabular distraction, leading to an overall cup survivorship of 90.6%. Of the remaining 48 patients, 46 (95.8%) had evidence of radiographic bridging callus of the chronic pelvic discontinuity at their last clinical follow-up. CONCLUSIONS: To our knowledge, in the largest series to date, acetabular distraction has proven to be a viable treatment for acetabular bone loss with a chronic pelvic discontinuity, with excellent early survivorship and radiographic evidence of bridging callus. Future studies with longer follow-ups are needed to further monitor the efficacy of this technique. LEVEL OF EVIDENCE: Level III, Retrospective Comparative Study.

Impact of Chronic Opioid Use on Postoperative Mobility Recovery and Patient-Reported Outcomes: A Propensity-Matched Study.

BACKGROUND: Opioid use prior to total joint arthroplasty may be associated with poorer postoperative outcomes. However, few studies have reported the impact on postoperative recovery of mobility. We hypothesized that chronic opioid users would demonstrate impaired objective and subjective mobility recovery compared to nonusers. METHODS: A secondary data analysis of a multicenter, prospective observational cohort study in which patients used a smartphone-based care management platform with a smartwatch for self-directed rehabilitation following hip or knee arthroplasty was performed. Patients were matched 2:1 based on age, body mass index, sex, procedure, Charnley class, ambulatory status, orthopedic procedure history, and anxiety. Postoperative mobility outcomes were measured by patient-reported ability to walk unassisted at 90 days, step counts, and responses to the 5-level EuroQol-5 dimension 5-level, compared by Chi-square and student's t-tests. Unmatched cohorts were also compared to investigate the impact of matching. RESULTS: A total of 153 preoperative chronic opioid users were matched to 306 opioid-naïve patients. Age (61.9 ± 10.5 versus 62.1 ± 10.3, P = .90) and sex (53.6 versus 53.3% women, P = .95) were similar between groups. The proportion of people who reported walking unassisted for 90 days did not vary in the matched cohort (87.8 versus 90.7%, P = .26). Step counts were similar preoperatively and 1-month postoperatively but were lower in opioid users at 3 and 6 months postoperatively (4,823 versus 5,848, P = .03). More opioid users reported moderate to extreme problems with ambulation preoperatively on the 5-level EuroQol-5 dimension 5-level (80.6 versus 69.0%, P = .02), and at 6 months (19.2 versus 9.3%, P = .01). CONCLUSIONS: Subjective and objective measures of postoperative mobility were significantly reduced in patients who chronically used opioid medications preoperatively. Even after considering baseline factors that may affect ambulation, objective mobility metrics following arthroplasty were negatively impacted by preoperative chronic opioid use.

Predictability of implant sizes during cruciate-retaining total knee arthroplasty using an image-free hand-held robotic system.

The use of appropriately sized implants is critical for achieving optimal gap balance following total knee arthroplasty (TKA). Inappropriately sized implants could result in several complications. Robot-assisted TKA (RA-TKA) using CT-based pre-operative planning predicts implant sizes with high accuracy. There is scant literature describing the accuracy of image-free RA-TKA in predicting implant sizes. The purpose of this study was to assess the accuracy of an image-free robotic system in predicting implant sizes during RA-TKA. Patients who underwent cruciate-retaining RA-TKA for primary osteoarthritis, using an image-free hand-held robotic system were studied. The predicted and implanted sizes of the femoral component, tibial component and polyethylene insert, for 165 patients, were recorded. Agreement between robot-predicted and implanted component sizes was assessed in percentages, while reliability was assessed using Cohen's weighted kappa coefficient. The accuracy of the robotic system was 63% (weighted-kappa = 0.623, P < 0.001), 94% (weighted-kappa = 0.911, P < 0.001) and 99.4% (weighted-kappa = 0.995, P < 0.001), in predicting exact, ± 1 and ± 2 sizes of the femoral component, respectively. For the tibial component, an accuracy of 15.8% (weighted-kappa = 0.207, P < 0.001), 55.8% (weighted-kappa = 0.378, P < 0.001) and 76.4% (weighted-kappa = 0.568, P < 0.001) was noted, for predicting exact, ± 1 and ± 2 sizes respectively. An accuracy of 88.5%, 98.2% and 100%, was noted for predicting exact, ± 1 and ± 2 sizes of the polyethylene insert respectively. Errors in predicting accurate implant sizes could be multi-factorial. Though the accuracy of image-free RA-TKA with respect to alignment and component positioning is established, the surgeon's expertise should be relied upon while deciding appropriate implant sizes.

Patients With Significant Medical Comorbidities May Benefit from Unicompartmental Knee Arthroplasty Over Total Knee Arthroplasty.

Many studies have compared outcomes in total knee arthroplasty (TKA) versus unicompartmental knee arthroplasty (UKA); however, to the authors' knowledge, there is no study evaluating complication rates in patients with significant comorbidities. The purpose of this retrospective study was to compare the incidence of postoperative complications, readmission and reoperation rates, length of stay (LOS), and discharge location for patients with significant medical comorbidities undergoing TKA versus UKA. Using the NSQIP database from 2008 to 2018, patients were identified by CPT code (27447 or 27446) and admission diagnostic code of primary osteoarthritis and included in the study if they had an American Society of Anesthesia score greater than or equal to 3. Chi-square test was used to compare categorical variables and t-test for continuous variables. Multivariate regression was used to compare outcomes of interest between groups. A total of 167,054 patients were analyzed with 97.3% undergoing TKA. TKA patients had a greater overall complication rate than those undergoing UKA (p < 0.001). Readmission rates were approximately 1.5 times higher in TKA compared with UKA (p = 0.002), while no statistically significant difference was discovered in reoperation rates (p = 0.868). TKA was also associated with decreased rates of same day discharge, discharge within 24 hours of surgery, and discharge home (p < 0.001, <0.001, and <0.001, respectively). This study found an increase in complication rates, readmission rates, and LOS, along with a lower likelihood of discharge home when undergoing a TKA. These findings suggest that patients with significant medical comorbidities at baseline may benefit from UKA over TKA when anatomically indicated.

The Dome Technique for Managing Massive Anterosuperior Medial Acetabular Bone Loss in Revision Total Hip Arthroplasty: Short-Term Outcomes.

Purpose: The dome technique is a technique used in performance of revision total hip arthroplasty (THA) involving intraoperative joining of two porous metal acetabular augments to fill a massive anterosuperior medial acetabular bone defect. While excellent outcomes were achieved using this surgical technique in a series of three cases, short-term results have not been reported. We hypothesized that excellent short-term clinical and patient reported outcomes could be achieved with use of the dome technique. Materials and Methods: A multicenter case series was conducted for evaluation of patients who underwent revision THA using the dome technique for management of Paprosky 3B anterosuperior medial acetabular bone loss from 2013-2019 with a minimum clinical follow-up period of two years. Twelve cases in 12 patients were identified. Baseline demographics, intraoperative variables, surgical outcomes, and patient reported outcomes were acquired. Results: The implant survivorship was 91% with component failure requiring re-revision in only one patient at a mean follow-up period of 36.2 months (range, 24-72 months). Three patients (25.0%) experienced complications, including re-revision for component failure, inter-prosthetic dual-mobility dissociation, and periprosthetic joint infection. Of seven patients who completed the HOOS, JR (hip disability and osteoarthritis outcome score, joint replacement) survey, five patients showed improvement. Conclusion: Excellent outcomes can be achieved using the dome technique for management of massive anterosuperior medial acetabular defects in revision THA with survivorship of 91% at a mean follow-up period of three years. Conduct of future studies will be required in order to evaluate mid- to long-term outcomes for this technique.

Systematic Exposure in Revision Total Hip Arthroplasty: The Posterior Approach.

As indications for total hip arthroplasty (THA) continue to expand, and patients continue to live longer with more active lifestyles, the incidence of revision THA is expected to rise. General orthopaedic surgeons are now beginning to consider doing revision THA surgery because of the increased revision burden being experienced nationwide. While classical approaches to the hip can be used for simple revisions, extensile exposure techniques in conjunction with selective soft-tissue releases are often required for adequate visualization for more complex revision cases. This review provides a systematic approach to surgical exposure for revision THA using the posterior approach. The surgeon should follow a stepwise progression to obtain safe, adequate, and reproducible visualization of both the acetabulum and the proximal femur.

Evaluating the Social Impact of a Proposed Orthopedic Center of Excellence in Northern Tanzania: A Novel Use of the Impact Multiple of Money Methodology.

BACKGROUND: Musculoskeletal injuries-often a result of Road Traffic Accidents (RTAs)-represent a significant burden in sub-Saharan Africa. RTA victims are faced with lifelong disability and diminished employment. Northern Tanzania in particular lacks the orthopedic surgical capacity needed to provide patients with definitive surgical fixation. While there is great potential in establishing an Orthopedic Center of Excellence (OCE), the precise social impact of such an initiative is currently unknown. METHODS: To demonstrate the social value of an orthopedic OCE in Northern Tanzania, this paper proposes a methodology for calculating social impact. This methodology draws upon RTA-related Disability Adjusted Life Years (DALYs), current and projected surgical complication rates, anticipated changes in surgical volume, and average per capita income to quantify how much social value can be gained by mitigating the impact of RTAs. These parameters can be utilized to calculate an impact multiplier of money (IMM), stating the social returns on each dollar invested. RESULTS: Modeling exercises demonstrate that improvements in the complication rate and surgical volume over the current baseline results in significant social impact. In the best-case scenario, the COE is expected to yield over $131 million over 10 years, with an IMM of 13.19. CONCLUSIONS: Investments in orthopedic care will yield significant dividends, as demonstrated by our novel methodology. The cost-effectiveness of the OCE is comparable to, if not greater, than many other global health initiatives. More broadly, the IMM methodology can be used to quantify the impact of other projects aimed at reducing long-term injury.

A Systematic Approach to Revision Total Knee Arthroplasty.

With the recent increase in primary total knee arthroplasties and the associated rise in failures of the index operation, there has been growing demand for orthopaedic surgeons to perform revision procedures. The orthopaedic surgeon performing revision total knee arthroplasty should be knowledgeable about the various etiologies of primary total knee arthroplasty failure, the steps for proper patient evaluation, and important factors in the preoperative planning process. A systematic methodology for obtaining surgical exposure, strategies for reconstruction, fundamentals of soft-tissue closure, and postoperative care also should be reviewed.

The "Wind Surf" Deformity-Correcting Fixed Flexion Deformity and Hyperextension in Bilateral CAS TKA.

Severe knee arthritis can result in complex coronal and sagittal angular deformities. Windswept deformity is used to describe a varus deformity and contralateral valgus deformity. We recognized a new sagittal pattern at the time of computer-assisted surgery (CAS) in total knee arthroplasty (TKA) in which one knee has a fixed flexion deformity (FFD), while the contralateral knee has a hyperextension deformity. We propose to define it as "wind surf" deformity mimicking the opposite pull of the wind and a surfer. The incidence of "wind surf" deformity in this series was 0.96% among a cohort of 2,291 bilateral TKAs performed between 2013 and 2018. Twenty-two patients were identified with an FFD of 5° to 20° on one knee and recurvatum of -5° to -20° on the contralateral knee. Additional bone resection and soft-tissue releases were performed for the FFD with a goal to maintain residual 1° to 3° of flexion. Minimal bone resection and soft-tissue disruption were performed on the knee with hyperextension with a goal to maintain 5° to 7° of flexion. These opposite strategies applied with the help of CAS prevented recurrence resulting in satisfactory clinical results at 2-year follow-up. The "wind surf" deformity variant should be identified in patients presenting with severe knee arthritis to guide surgical treatment, prevent recurrence, and obtain favorable clinical patient outcomes.

Evolution of total hip arthroplasty in patients younger than 30 years of age: A systematic review and meta-analysis.

INTRODUCTION: While surgical technique and implant technology for total hip arthroplasty (THA) has improved over the years, it is unclear whether recent progress has translated to improved clinical outcomes for young patients. The goal of this study is to determine trends in (1) indications, (2) surgical technique (3) clinical and radiographic outcomes, and (4) survivorship for THA in patients younger than 30 years of age. METHODS: MedLine, Cochrane, EMBASE, and Google Scholar were searched using several key phrases for articles focusing on THA performed on patients younger than 30 years of age between 1971 and 2020. A total of 34 qualifying articles were identified and stratified into three groups according to operative years and compared to one another on the basis of (1) indications; (2) fixation technique; (3) implant design; (4) clinical and radiographic outcomes; and (7) survivorship. RESULTS: The mean patient age at index THA were 20.5 (9-30), 22.1 (11-30) and 21.5 (10-30) years, respectively, for each study group. Over time, patients underwent fewer THAs for JRA (Juvenile Rheumatoid Arthritis) (p < 0.001) but more for post-treatment and iatrogenic avascular necrosis (p < 0.001; p < 0.001). Early THAs primarily used metal on UHMWPE (Ultra high molecular weight polyethylene) (71.7%, p < 0.001), modern THA predominantly use ceramic on HXLPE (Highly cross-linked polyethylene) (42.5%, p < 0.001). Early fixation methods used cement (60.4%, p < 0.001), and modern fixation primarily use press fit technology (95.9%, p < 0.001). Prevalence of radiographic loosening decreased significantly (p < 0.001) over time. There was no significant difference in clinical improvement on HHS. Lastly, fewer patients required THA revision in recent decades (p < 0.001). CONCLUSIONS: Advances in surgical technique and technology have served to improve implant longevity. Surprisingly, subjective clinical scores showed no significant improvement over time, suggesting that early iterations of THA were extremely successful.

The Complex Process of Using the Interconnected Knee Arthroplasty Device Clearance Pathway.

Background: The clearance of medical devices by the US Food and Drug Administration (FDA) has remained largely unchanged since 1976, when the Medical Device Amendments Act established a system classifying devices into 3 categories based on safety risk to the consumer. The system allows for the clearance of many orthopedics devices through the 510(k) premarket pathway, which is based on "predicate ancestors," previously cleared devices that are "substantially equivalent." Purpose: We sought to trace the predicate ancestors of modern total knee arthroplasty (TKA) devices, specifically those recently cleared for marketing by the 510(k) pathway that claim substantial equivalence to prior devices, despite potential differences in material science and design. In addition, we aimed to document which TKA devices cleared by the 510(k) pathway have substantial equivalence to devices that have since been recalled by the FDA. Methods: To create a comprehensive list of TKA devices, we used FDA Classification Process Codes corresponding to knee arthroplasty to search the FDA's databases from May 28, 1976, the start of the 510(k) process, to May 1, 2021. Of 1309 resulting devices, 89 were excluded as not related to arthroplasty. For each of the remaining devices, we analyzed the descendant devices that claimed substantial equivalence, either directly or indirectly. We used data of recalled designs to determine both the absolute number of recalled devices and the number of currently cleared devices that presented substantial equivalence claims upon predicates that have since been recalled. Results: Of 1220 knee devices cleared or approved, 6 (0.5%) were approved through the premarket approval application (PMA) process, and 1214 (99.5%) were cleared through the 510(k) pathway. Of the 1214 cleared devices, 217 (17.9%) have been recalled and 204 (16.8%) have ties to at least 1 recalled predicate device linked through generational claims of substantial equivalence. We found 90 devices (7.4%) linked directly to a recalled predicate device. Conclusions: Most knee arthroplasty devices are cleared for marketing through reliance on a complex web of equivalency to previously cleared predicates. We found that many TKA devices thus connected were cleared decades apart, with multiple iterations of design and material modifications. Many currently marketed TKA devices have claimed equivalency to predicates that have been recalled. Our findings suggest the need for novel regulatory strategies that might further patient safety while balancing the unwanted effects of regulatory burden.

Hospitalized for poverty: orthopaedic discharge delays due to financial hardship in a tertiary hospital in Northern Tanzania.

BACKGROUND: Musculoskeletal injury contributes significantly to the burden of disease in Tanzania and other LMICs. For hospitals to cope financially with this burden, they often mandate that patients pay their entire hospital bill before leaving the hospital. This creates a phenomenon of patients who remain hospitalized solely due to financial hardship. This study aims to characterize the impact of this policy on patients and hospital systems in resource-limited settings. METHODS: A mixed-methods study using retrospective medical record review and semi-structured interviews was conducted at a tertiary hospital in Moshi, Tanzania. Information regarding patient demographics, injury type, days spent in the ward after medical clearance for discharge, and hospital invoices were collected and analyzed for orthopaedic patients treated from November 2016 to June 2017. RESULTS: 346 of the 867 orthopaedic patients (39.9%) treated during this time period were found to have spent additional days in the hospital due to their inability to pay their hospital bill. Of these patients, 72 patient charts were analyzed. These 72 patients spent an average of 9 additional days in the hospital due to financial hardship (range: 1-64 days; interquartile range: 2-10.5 days). They spent an average of 112,958 Tanzanian Shillings (TSH) to pay for services received following medical clearance for discharge, representing 12.3% of the average total bill (916,840 TSH). 646 hospital bed-days were spent on these 72 patients when they no longer clinically required hospitalization. 7 (9.7%) patients eloped from the hospital without paying and 24 (33.3%) received financial assistance from the hospital's social welfare office. CONCLUSIONS: Many patients do not have the financial capacity to pay hospital fees prior to discharge. This reality has added significantly to these patients' overall financial hardship and has taken hundreds of bed-days from other critically ill patients. This single-institution, cross-sectional study provides a deeper understanding of this phenomenon and highlights the need for changes in the healthcare payment structure in Tanzania and other comparable settings.

Local Trends in Total Joint Arthroplasty and Orthopaedic Surgeon Distribution in the United States.

INTRODUCTION: Total joint arthroplasty (TJA) volume and the number of orthopaedic surgeons in the United States have increased in recent years, but local growth variation has not been studied. This study assesses recent changes in state-level distribution of orthopaedic surgeons in the United States and corresponding local trends in TJA volume. METHODS: Data from the National Inpatient Sample database (2000 to 2014) were reviewed. Urban versus rural setting and teaching versus nonteaching hospitals were identified among TJA procedures for comparison. Data from the American Academy of Orthopaedic Surgeons (2002 to 2016) detailing orthopaedic surgeon practice location were evaluated, and linear regression analysis was used to correlate state population data with orthopaedic surgeon density. RESULTS: From 2000 to 2014, there was a 0.1% to 0.3% (P < 0.01) annual decrease in the proportion of TJA procedures conducted in rural hospitals. No notable change was observed in the proportion of TJA procedures conducted at urban teaching versus nonteaching hospitals. Linear regression analysis demonstrated that decreased state population was associated with higher orthopaedic surgeon density (adjusted R2 = 0.114, P < 0.01). States with a higher percentage of population living in rural areas had a lower density of orthopaedic surgeons in the South region and a higher density of orthopaedic surgeons in the remainder of the county. CONCLUSIONS: Less populated, rural states have a higher density of orthopaedic surgeons than states with increased population and less rural areas. Although TJA volume has increased since 2000, the proportion of TJA procedures conducted at rural hospitals has decreased. No change was found in the proportion of TJA procedures conducted at urban teaching versus nonteaching hospitals. This may indicate that more patients living in rural areas are seeking TJA care in urban centers. Future studies are needed to confirm this and ensure that patients living in rural areas have appropriate access to TJA care.

Early Outcome Trends of Unicompartmental Knee Arthroplasty in Patients With Morbid Obesity: A Potential for Outpatient Surgery.

BACKGROUND: Elevated body mass index (BMI) was previously considered a contraindication to unicompartmental knee arthroplasty (UKA). This study sought to determine if outcomes following UKA in patients with elevated BMI have improved over the years. We hypothesized that operative times and length of stay (LOS) following UKA would significantly decrease, while discharge to home rates would increase across all BMI cohorts, especially those with a BMI > 40. METHODS: Using the National Surgical Quality Improvement Program registry, surgical cases categorized using the Current Procedural Terminology code 27446 for UKA with a recorded height and weight were included. Three BMI cohorts were created: BMI I (BMI < 30), BMI II (30 ≤ BMI ≤ 40), and BMI III (BMI > 40). Each BMI group was subclassified temporally by year of operation: Years A (2006-2009), Years B (2010-2014), and Years C (2015-2019). RESULTS: A total of 14,114 patients were included. For BMI III, both operative time (P < .001) and LOS (P < .001) significantly decreased over the Years cohorts. Discharge home rates increased from 88.3% to 94.4% in BMI III (P = .001). All BMI cohorts saw similar changes in discharge patterns, 30-day readmissions, and reoperations within 30 days in recent years. CONCLUSION: This study found that operative times and LOS have decreased significantly in patients with morbid obesity over the past 14 years, while more patients are being discharged home without being readmitted or reoperated on in the first month. As surgeons continue to improve their operative and reconstructive techniques, this study suggests that patients with elevated BMI should be considered candidates to undergo UKA procedures in ambulatory surgery centers or in hospitals with a rapid recovery unit.