Preoperative Depression Is Associated With Increased Short-term Complications But Equivalent Long-term Outcomes in Total Knee Arthroplasty.

Concomitant depression negatively impacts outcomes following total knee arthroplasty (TKA). Patient-Reported Outcomes Measurement Information System (PROMIS) surveys are validated measures that quantify depression, pain, and physical function. We hypothesized that higher preoperative PROMIS-depression scores would be associated with inferior outcomes following TKA. A total of 258 patients underwent primary TKA at a tertiary academic center between June 2018 and August 2020. PROMIS scores were collected preoperatively and at 6 weeks, 3 months, 1 year, and 2 years postoperatively. Patients with preoperative PROMIS depression scores of 55 or greater were considered PROMIS depressed (PD) and patients with scores less than 55 were considered not PROMIS depressed (ND). The primary outcomes were changes in PROMIS scores. Secondary outcomes included total and daily mean morphine milligram equivalents (MME) received during admission as well as 90-day hospital readmission and 2-year all-cause revision rates. There were 66 (25.58%) patients in the PD group and 192 (74.42%) in the ND group. Patients in the PD group had improved depression scores at all follow-up intervals (P<.001) and decreased pain scores at 1 year (P=.016). Both groups experienced similar changes in function scores at each follow-up interval. Patients in the PD group had higher total (P=.176) and daily (P=.433) mean MME use while admitted. Ninety-day hospital readmissions were higher in the PD group (P=.002). There were no differences in 2-year revision rates (P=.648). Preoperative PROMIS-depression scores of 55 or greater do not negatively impact postoperative function, depression, or pain, and patients with these scores have greater improvement in depression and pain at certain intervals. Patients in the PD group had higher readmission rates. [Orthopedics. 2024;47(1):40-45.].

Isolated Liner Exchange Versus All-Component Revision for Instability After Total Knee Arthroplasty.

BACKGROUND: Instability is a common cause for revision total knee arthroplasty (TKA). The risks and benefits of polyethylene liner exchange (LE) as compared to full metal component revision continue to be debated. The purpose of this study was to investigate the success rate and complication profiles of revision TKA for instability based on surgical procedure. METHODS: This was a retrospective study of patients undergoing revision TKA for instability from 2015 to 2019. Patients with prior revisions were excluded. 42 patients undergoing isolated polyethylene LE without an increase in constraint were compared with 48 patients undergoing full component revision revision (FCR) of both tibial and femoral components. The primary outcome was differences in rerevision for instability. Noninstability reoperations, 90-day readmissions, and lengths-of-stay were also compared. RESULTS: LEs had a 10.1% higher rerevision for instability rate that approached statistical significance (LE 14.3% versus FCR 4.2%, P = .092). Additionally, FCR had a 4.2% rate of aseptic loosening and a 4.2% rate of periprosthetic-joint-infection, whereas LE had none (P = .181). FCR also had a longer length-of-stay (FCR 3.0 ± 1.3 versus LE: 1.8 ± 0.9 days, P < .001). No differences were found in 90-day readmissions (LE 7.1% versus FCR 4.2%, P = .661). CONCLUSION: All component revision may have a higher success rate than isolated LE in addressing instability but is associated with higher rates of surgical complications. With appropriate patient selection and risk-benefit discussion, isolated LE may be a reasonable surgical option for TKA instability with a lower complication profile and length-of-stay.

Initiation of Bisphosphonates Prior to Total Joint Arthroplasty Does Not Lower Periprosthetic Fracture Risk.

BACKGROUND: Many patients are diagnosed with osteoporosis shortly prior to scheduling total joint arthroplasty (TJA). The purpose of this study was to determine if initiation of bisphosphonates prior to TJA decreased the risks of periprosthetic fractures (PPFx). METHODS: A national database was used to identify all patients diagnosed with osteoporosis prior to primary TJA. Patients who had osteoporosis without preoperative bisphosphonate use were designated as our control group. Patients on preoperative bisphosphonates were stratified based on duration and timing of bisphosphonate use: long-term preoperative users (initiation 3 to 5 years preoperatively), intermediate-term preoperative users (initiation 1 to 3 years preoperatively), and short-term preoperative users (initiation 0 to 1 year preoperatively). Rates of PPFx at 90-day and 2-year follow-up were compared between groups. RESULTS: In patients undergoing primary total hip arthroplasty, there was no difference in PPFx rate between our control group and preoperative bisphosphonate users of all durations at 90-day (P = .12) and 2-year follow-up (P = .22). In patients undergoing primary total knee arthroplasty, there was no difference in PPFx rate between our control group and preoperative bisphosphonate users of all durations at 90-day (P = .76) and 2-year follow-up (P = .39). CONCLUSIONS: In patients undergoing primary TJA, preoperative bisphosphonate users did not have a decreased PPFx rate compared to our control group at 90-day and 2-year follow-up. Our findings suggest that preoperative bisphosphonate use, regardless of the duration of treatment, does not confer protective benefits against PPFx in patients undergoing TJA. LEVEL OF EVIDENCE: Prognostic Level III.

Intra-Articular Corticosteroid Injections Into a Preexisting Total Knee Arthroplasty are Associated With Increased Risk of Periprosthetic Joint Infection and Revision.

Background: This study aims to determine the risks of periprosthetic joint infection (PJI) and revision associated with injecting a preexisting total knee arthroplasty (TKA) with intra-articular corticosteroids (IACSs). Methods: The PearlDiver database was used to identify patients who underwent elective, primary TKA between 2015 and 2019. Patients who received IACS injections into the ipsilateral knee within 1 year after their primary TKA were matched 2:1 on age, gender, and Charlson comorbidity index and compared to a no-injection control group. The incidence of PJI at 1 year postoperatively and revision at 2 years postoperatively were compared between groups. Results: A total of 27,059 patients were in the injection cohort and 54,116 patients in the control cohort. The overall PJI rate was 1.3% in the injection cohort and 0.8% in the control cohort (P < .001). The rate of PJI increased with the number of post-TKA IACS injections received: 1 injection (1.3%), 2 injections (1.4%), and >3 injections (1.8%) (P < .001 for all, compared to controls). The revision rate was 3.1% in the injection cohort and 1.3% in the control cohort (P < .001). Revision rates increased with the number of post-TKA IACS injections received: 1 injection (2.5%), 2 injections (4.2%), and >3 injections (7.3%) (P < .001 for all, compared to controls). Conclusions: IACS injections into a preexisting TKA are associated with an incremental increased risk of prosthetic joint infection and revision. Considering the potential deleterious impact of PJI and complexity of revision procedures, IACS injections into a preexisting TKA should be strongly discouraged.

Metallosis in Total Hip Arthroplasty.

¼ Metallosis is a rare but significant complication that can occur after total hip arthroplasty (THA) for a variety of reasons but most commonly in patients with metal-on-metal implants.¼ It is characterized by the visible staining, necrosis, and fibrosis of the periprosthetic soft tissues, along with the variable presence of aseptic cysts and solid soft tissue masses called pseudotumors secondary to the corrosion and deposition of metal debris.¼ Metallosis can present with a spectrum of complications ranging from pain and inflammation to more severe symptoms such as osteolysis, soft tissue damage, and pseudotumor formation.¼ Workup of metallosis includes a clinical evaluation of the patient's symptoms, imaging studies, serum metal-ion levels, and intraoperative visualization of the staining of tissues. Inflammatory markers such as erythrocyte sedimentation rate and C-reactive protein along with intraoperative frozen slice analysis may be useful in certain cases to rule out concurrent periprosthetic joint infection.¼ Management depends on the severity and extent of the condition; however, revision THA is often required to prevent rapid progression of bone loss and tissue necrosis.

Higher Complication Rate in COVID-19 Recovered Patients Undergoing Primary Total Joint Arthroplasty.

BACKGROUND: There is limited data reviewing complication risks associated with total joint arthroplasty (TJA) after recovering from COVID-19. This study evaluated complications within 90 days of TJA in patients who had a COVID-19 diagnosis at varying intervals prior to surgery versus a non-COVID-19 cohort. METHODS: A large national database was used to identify patients diagnosed with COVID-19 in the six months prior to total hip arthroplasty (THA) or total knee arthroplasty. The incidence of complications within 90 days of surgery was recorded and compared to a COVID-19 negative control group matched 1:3 for age range in 5-year intervals, Charlson Comorbidity Index, and sex. There were 7,780 patients included in the study; 5,840 (75.1%) never diagnosed with COVID-19, 1,390 (17.9%) who had a COVID-19 diagnosis 0 to 3 months prior to surgery, and 550 (7.1%) who had a COVID-19 diagnosis 3 to 6 months prior to surgery. RESULTS: When compared to their COVID negative controls, patients who had a COVID-19 diagnosis 0 to 3 months prior to surgery had significantly higher rates of readmission (14.0 versus 11.1%, P = .001), pneumonia (2.2 versus 0.7%, P < .001), deep vein thrombosis (DVT) (3.3 versus 1.9%, P = .001), kidney failure (2.4 versus 1.4%, P = .006), and acute respiratory distress syndrome (1.4 versus 0.7%, P = .01). Patients who had a COVID-19 diagnosis 3 to 6 months prior to surgery had significantly higher rates of pneumonia (2.0 versus 0.7%, P = .002) and DVT (3.6 versus 1.9%, P = .005) when compared to their COVID negative controls. CONCLUSION: Patients diagnosed with COVID-19 within three months prior to TJA have an increased risk of 90-day postoperative complications. Risk for pneumonia and DVT remains elevated even when surgery was performed as far as 3 to 6 months after COVID-19 diagnosis.

Revision total knee arthroplasty for arthrofibrosis improves range of motion.

PURPOSE: Arthrofibrosis after primary total knee arthroplasty (TKA) is a significant contributor to patient dissatisfaction. While treatment algorithms involve early physical therapy and manipulation under anaesthesia (MUA), some patients ultimately require revision TKA. It is unclear whether revision TKA can consistently improve these patient's range of motion (ROM). The purpose of this study was to evaluate ROM when revision TKA was performed for arthrofibrosis. METHODS: A retrospective study of 42 TKA's diagnosed with arthrofibrosis from 2013 to 2019 at a single institution with a minimum 2-year follow-up was performed. The primary outcome was ROM (flexion, extension, and total arc of motion) before and after revision TKA, and secondary outcomes included patient reported outcomes information system (PROMIS) scores. Categorical data were compared using chi-squared analysis, and paired samples t tests were performed to compare ROM at three different times: pre-primary TKA, pre-revision TKA, and post-revision TKA. A multivariable linear regression analysis was performed to assess for effect modification on total ROM. RESULTS: The patient's pre-revision mean flexion was 85.6 degrees, and mean extension was 10.1 degrees. At the time of the revision, the mean age of the cohort was 64.7 years, the average body mass index (BMI) was 29.8, and 62% were female. At a mean follow-up of 4.5 years, revision TKA significantly improved terminal flexion by 18.4 degrees (p < 0.001), terminal extension by 6.8 degrees (p = 0.007), and total arc of motion by 25.2 degrees (p < 0.001). The final ROM after revision TKA was not significantly different from the patient's pre-primary TKA ROM (p = 0.759). PROMIS physical function, depression, and pain interference scores were 39 (SD = 7.72), 49 (SD = 8.39), and 62 (SD = 7.25), respectively. CONCLUSION: Revision TKA for arthrofibrosis significantly improved ROM at a mean follow-up of 4.5 years with over 25 degrees of improvement in the total arc of motion, resulting in final ROM similar to pre-primary TKA ROM. PROMIS physical function and pain scores showed moderate dysfunction, while depression scores were within normal limits. While physical therapy and MUA remain the gold standard for the early treatment of stiffness after TKA, revision TKA can improve ROM. LEVEL OF EVIDENCE: IV.

Impact of Antibiotic-Impregnated Spacer Design in the Treatment of Periprosthetic Hip Infection.

Background: Although 2-stage exchange arthroplasty, consisting of temporary insertion of an antibiotic-impregnated cement spacer (AICS), is considered the standard of care for chronic periprosthetic joint infection (PJI) in total hip arthroplasty (THA), a consensus on the AICS design has not yet been established. Ceramic-on-polyethylene AICSs (Poly-AICS) are theorized to cause less pain and better function than cement-on-bone AICS (CemB-AICS) but use non-antibiotic-impregnated components that may harbor bacteria. This study evaluates the impact of spacer design on infection-free survivorship following THA reimplantation as well as pain and function during the interim AICS stage. Methods: A retrospective review was performed of all cases of THA PJI treated with either Poly-AICS or CemB-AICS at a single high-volume academic center. Data were collected until the final follow-up after THA reimplantation with an average follow-up duration of 2.6 years. The primary outcome was infection-free survivorship after the final reimplantation. Secondary outcomes included postoperative pain scores, opioid use, time to ambulation, length of stay, complications, and discharge disposition. Results: A total of 99 cases (67 CemB-AICS; 32 Poly-AICS) were included. There were no baseline differences between the 2 groups. There were no differences in infection-free survivorship after reimplantation in survivorship curve comparisons (P = .122) and no differences in postoperative inpatient pain scores, opioid use, length of stay, time to ambulation, complications, or discharge disposition during the AICS stage. Conclusions: Patients with THA PJI treated with Poly-AICS did not have worse infection-related outcomes despite the use of non-antibiotic-impregnated components but also did not appear to have less pain or improved function during the early AICS stage.

Increased Prevalence, Complications, and Costs of Smokers Undergoing Total Knee Arthroplasty.

Given a national push toward bundled payment models, the purpose of this study was to examine the prevalence as well as the effect of smoking on early inpatient complications and cost following elective total knee arthroplasty (TKA) in the United States across multiple years. Using the nationwide inpatient sample, all primary elective TKA admissions were identified from 2012 to 2014. Patients were stratified by smoking status through a secondary diagnosis of "tobacco use disorder." Patient characteristics as well as prevalence, costs, and incidence of complications were compared. There was a significant increase in the rate of smoking in TKA from 17.9% in 2012 to 19.2% in 2014 (p < 0.0001). The highest rate was seen in patients < 45 years of age (27.3%). Hospital resource usage was significantly higher for smokers, with a length of stay of 3.3 versus 2.9 days (p < 0.0001), and hospital costs of $16,752 versus $15,653 (p < 0.0001). A multivariable logistic model adjusting for age, gender, and comorbidities showed that smokers had an increased odds ratio for myocardial infarction (5.72), cardiac arrest (4.59), stroke (4.42), inpatient mortality (4.21), pneumonia (4.01), acute renal failure (2.95), deep vein thrombosis (2.74), urinary tract infection (2.43), transfusion (1.38) and sepsis (0.65) (all p < 0.0001). Smoking is common among patients undergoing elective TKA, and its prevalence continues to rise. Smoking is associated with higher hospital costs as well as higher rates of immediate inpatient complications. These findings are critical for risk stratification, improving of bundled payment models as well as patient education, and optimization prior to surgery to reduce costs and complications.

High-Dose Vitamin D Supplementation Can Correct Hypovitaminosis D Prior to Total Knee Arthroplasty.

BACKGROUND: Vitamin D deficiency in the perioperative surgical period is associated with inferior surgical outcomes. There are no established preoperative supplementation regimens in the orthopedic literature. The purpose of this study is to compare the efficacy between 2 different supplementation regimens of vitamin D prior to total knee arthroplasty. METHODS: We conducted a retrospective analysis of 174 patients identified as vitamin D deficient (25(OH)D < 30 ng/mL) who received one of 2 vitamin D supplementation protocols: (1) daily supplementation with D3 on a sliding scale from 1000 to 6000 IU or (2) a loading dose of 50,000 IU D3 weekly for 4 weeks then 2000 IU/d. Serum vitamin D levels were measured at 3 months and 1 month preoperatively. RESULTS: Mean patient age was 65.5(±8.6) years, and 54.6% were female. Deficiency was corrected in 73.3% of patients in the loading dose group and 42.4% of patients in the daily, low-dose group [χ2 (1, N = 174) = 16.53, P < .001]. Patients in the loading dose group also achieved a greater average correction in vitamin D levels. CONCLUSION: This is the first study to compare preoperative vitamin D supplementation protocols. A loading dose regimen of 50,000 IU weekly for 4 weeks followed by a maintenance dose of 2000 IU/d more effectively corrects vitamin D deficiency compared to a low-dose, daily regimen among total knee arthroplasty patients. We recommend this regimen for deficiency correction in patients who have been screened to be deficient in vitamin D preoperatively.

National Decline in Knee Fusions Performed for Salvage of Chronic Periprosthetic Total Knee Infections.

The primary purpose of this study was to study and compare rates of two salvage operations for patients with chronically infected total knee arthroplasties: (1) knee arthrodesis and (2) above knee amputation (AKA). An analysis was performed comparing the inpatient hospital characteristics and complications between the two procedures. Secondarily, we presented rates of all surgically treated periprosthetic total knee infections over a 6-year period. Using the Nationwide Inpatient Sample, we identified all patients with a periprosthetic infection (International Classification of Diseases, Ninth Revision [ICD-9] 996.66) from 2009 to 2014. Subsequently, we identified surgically treated total knee infections through the following ICD-9 codes: 00.80 (all component revision), 00.84 (liner exchange), 80.06 (removal of prosthesis), 84.17 (AKA), and 81.22 (knee fusion). From 2009 to 2014, the annual incidence of surgically treated total knee periprosthetic infections increased by 34.9% nationally, while the annual incidence of primary total knees increased by only 13.9%. Salvage operations (AKA and knee fusion) represented 5.8% of all surgically treated infections. The rate of knee fusions decreased from 1.9% of surgically treated infections in 2009 to 1.4% in 2014 (p < 0.05), while the rate of AKA stayed steady at 4.5% of cases over the 6-year period. Length of stay was significantly shorter in the knee fusion group (7.9 vs. 10.8 days, p < 0.05), but total hospital costs were higher (33,016 vs. 24,933, p < 0.05). In the multivariable adjusted model, patients undergoing knee fusion had significantly decreased odds of being discharged to skilled nursing facility (odds ratio: 0.42, 95% confidence interval: 0.31-0.58). The annual incidence of surgically treated periprosthetic total knee infections is increasing. The rate of knee arthrodesis for chronic periprosthetic total knee infections is decreasing. Reasons for this downward trend in knee fusions should be evaluated carefully as knee fusions have shown to have the potential advantage of improved mobility and decreased patient morbidity for chronic PJI. The level of evidence is III.

Nationwide Analysis of Lower Extremity Periprosthetic Fractures.

BACKGROUND: Although the annual incidence of primary total joint arthroplasty is increasing, trends in the annual incidence of periprosthetic fractures have not been established. This study aimed to define the annual incidence of periprosthetic fractures in the United States. METHODS: Inpatient admission data for 60,887 surgically treated lower extremity periprosthetic fractures between 2006 and 2015 were obtained from the National Inpatient Sample database. The annual incidence of periprosthetic fractures was defined as the number of new cases per year and presented as a population-adjusted rate per 100,000 US individuals. Univariable methods were used for trend analysis and comparisons between groups. RESULTS: The national annual incidence of periprosthetic fractures presented as a population-adjusted rate of new cases per year peaked in 2008 (2.72; 95% confidence interval [95% CI], 2.39-3.05), remained stable from 2010 (1.65; 95% CI, 1.45-1.86) through 2013 (1.67; 95% CI, 1.55-1.8) and increased in 2014 (1.99; 95% CI, 1.85-2.13) and 2015 (2.47; 95% CI, 2.31-2.62). The proportion of femoral periprosthetic fractures managed with total knee arthroplasty revision remained stable (Ptrend = .97) with an increase in total hip arthroplasty (THA) revision (Ptrend < .001) and concurrent decrease in open reduction and internal fixation (ORIF) (Ptrend < .001). Revision THA was significantly more costly than revision total knee arthroplasty (P = .004), and both were significantly more costly than ORIF (P < .001 for both). CONCLUSION: The annual incidence of periprosthetic fractures remained relatively stable throughout our study period. The proportion of periprosthetic fractures managed with revision THA increased, whereas ORIF decreased. Our findings are encouraging considering the significant burden an increase in periprosthetic fracture incidence would present to the health care system in terms of both expense and patient morbidity.

Activity Recommendations After Total Hip and Total Knee Arthroplasty.

¼: A formal unsupervised activity program should be recommended to all patients recovering from total knee arthroplasty (TKA) and total hip arthroplasty (THA). ¼: In a subset of all patients undergoing TKA or THA, studies have found that an unsupervised activity program may be as efficacious as supervised physical therapy (PT) after surgery. Certain patients with inadequate independent function may continue to benefit from supervised PT. ¼: For TKA, supervised telerehabilitation has also been proven to be an effective modality, with studies suggesting equivalent efficacy compared with supervised in-person PT. ¼: Following TKA, there is no benefit to the use of continuous passive motion or cryotherapy devices, but there are promising benefits from the use of pedaling exercises, weight training, and balance and/or sensorimotor training as adjuncts to a multidisciplinary program after TKA. ¼: No standardized postoperative limitations exist following TKA, and the return to preoperative activities should be dictated by an individual's competency and should consist of methods to minimize high impact stress on the joint. ¼: Despite traditional postoperative protocols recommending range-of-motion restrictions after THA, it is reasonable to recommend that hip precautions may not be needed routinely following elective primary THA.

Determining and Achieving Target Limb Length and Offset in Total Hip Arthroplasty Using Intraoperative Digital Radiography.

BACKGROUND: Achieving appropriate limb length and offset in total hip arthroplasty (THA) is challenging. Target limb length and offset may not always mean equal radiographic measurements bilaterally. The goal of this study is to introduce a method for determining as well as achieving target limb length and offset using digital radiographic measurements. METHODS: One hundred and two consecutive patients with unilateral hip osteoarthritis undergoing primary THA in the lateral decubitus position were included. Limb length and offset were measured on anterior-posterior pelvic radiographs preoperatively, intraoperatively, and postoperatively. Offset was defined as the length of a line parallel to the inter-teardrop line, extending from the edge of the ischium, at about the lower border of the ipsilateral obturator foramen, to the edge of the femoral cortex, usually at, or just below, the neck resection level. Target limb length was determined for each patient based on patient perception and severity of disease. Target offset equaled the contralateral limb. Using intraoperative digital radiography, adjustments were made until targets were achieved and the hip was stable. Patients were followed for an average of 4.2 years postoperatively. RESULTS: Limb length was within 5 mm of target measurements in 100% of patients and offset was within 5 mm of targets in 97.1%. Target measurements differed by >5 mm from the contralateral side in 2.0% of limb length and 2.9% of offset measurements. There were no significant differences between intraoperative and postoperative limb length (P = .261) or offset (P = .747) measurements. At final follow-up, there were no dislocations or reoperations and average Hip disability and Osteoarthritis Outcome Score for Joint Replacement was 95.78. CONCLUSION: Target limb length and offset goals can be determined for most patients undergoing THA. Targets are not always equal to the contralateral side. Intraoperative digital radiography can allow surgeons to accurately achieve target limb length and offset to within 5 mm in a homogenous cohort of patients with unilateral hip osteoarthritis with excellent clinical outcomes.

Smoking and Total Hip Arthroplasty: Increased Inpatient Complications, Costs, and Length of Stay.

BACKGROUND: Smoking is a potentially modifiable risk factor that may impact the overall outcomes of total hip arthroplasty (THA). In an era of bundled payments for THA, the purpose of this study was to evaluate, on a national level, the inpatient complications and additional costs of smokers undergoing THA. METHODS: The Nationwide Inpatient Sample was used to identify all primary elective THAs performed in the United States in 2014. This cohort was further stratified by smoking status. Inpatient hospital characteristics, costs, and complications rates were assessed. RESULTS: The Nationwide Inpatient Sample had 63,446 admissions recorded for primary THAs in 2014, corresponding to an estimated 317,230 cases nationwide. The smoking rate was 20.7%. Smokers were slightly yet significantly younger than nonsmokers (63.5 years vs 64.8 years; P < .0001). The smoking group had a significantly longer hospital stay and higher total hospital costs (both P < .0001). After using a multivariable logistic model adjusting for age, gender, and comorbidities, smokers were found to have a significantly higher odds ratio (OR [95% confidence interval {CI}]) for myocardial infarction (15.5 [5.0-47.5]), cardiac arrest (10.1 [2.2-47.6]), pneumonia (4.7 [2.4-9.1]), urinary tract infection (1.9 [1.4-2.7]), sepsis (13.1 [3.5-49.0]), acute renal failure (2.9 [2.2-3.7]), discharge to a skilled nursing facility (1.3 [1.2-1.4]), and mortality (11.7 [2.0-70.5]). CONCLUSIONS: Smoking remains a highly prevalent and important risk factor for complications in elective primary THA in the United States. Patients who smoke have a significantly higher rate of complications and generate significantly higher postoperative inpatient costs. These findings are important for risk stratification, bundled payment considerations, as well as perioperative patient education and intervention.

Increasing Burden of Total Hip Arthroplasty Revisions in Patients Between 45 and 64 Years of Age.

BACKGROUND: This study provides a comprehensive analysis of total hip arthroplasty (THA) revisions in the U.S. from 2007 to 2013. METHODS: International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes were used to identify all THA revisions in the Nationwide Inpatient Sample (NIS) from 2007 to 2013. The diagnoses leading to the revisions, types of revisions, major inpatient complications, and hospital and patient characteristics were compared between 2007 and 2013. Multivariable logistic regression models were used to calculate adjusted odds ratios (ORs) for complications in 2013 versus 2007. RESULTS: This study identified 320,496 THA revisions performed between 2007 and 2013. From 2007 to 2013, the THA revision rate adjusted for U.S. population growth increased by 30.4% in patients between 45 and 64 years of age and decreased in all other age groups. The rate of surgically treated THA dislocations decreased by 14.3% from 2007 to 2013 (p < 0.0001). The mean length of the hospital stay and hospital costs for THA revision were significantly lower in 2013 than in 2007 (4.6 versus 5.8 days and $20,463 versus $25,401 both p < 0.0001). A multivariable model showed that the odds of a patient undergoing THA revision having the following inpatient complications were significantly lower in 2013 than in 2007: deep vein thrombosis (OR = 0.57, p = 0.004), pulmonary embolism (OR = 0.45, p = 0.047), myocardial infarction (OR = 0.52, p = 0.003), transfusion (OR = 0.64, p < 0.0001), pneumonia (OR = 0.56, p < 0.0001), urinary tract infection (OR = 0.66, p < 0.0001), and mortality (OR = 0.50, p = 0.0009). Notably, the odds of being discharged to a skilled nursing facility were also lower in 2013 than in 2007 (OR = 0.71, p < 0.0001). CONCLUSIONS: The THA revision rate has significantly increased in patients between 45 and 64 years of age. However, the rate of surgically treated THA dislocations has decreased significantly. This may indicate that evolving techniques and implants are improving stability. The rate of inpatient complications following THA revision also decreased significantly from 2007 to 2013. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Digital Radiography in Total Hip Arthroplasty: Technique and Radiographic Results.

BACKGROUND: Obtaining the ideal acetabular cup position in total hip arthroplasty remains a challenge. Advancements in digital radiography and image analysis software allow the assessment of the cup position during the surgical procedure. This study describes a validated technique for evaluating cup position during total hip arthroplasty using digital radiography. METHODS: Three hundred and sixty-nine consecutive patients undergoing total hip arthroplasty were prospectively enrolled. Preoperative supine anteroposterior pelvic radiographs were made. Intraoperative anteroposterior pelvic radiographs were made with the patient in the lateral decubitus position. Radiographic beam angle adjustments and operative table adjustments were made to approximate rotation and tilt of the preoperative radiograph. The target for cup position was 30° to 50° abduction and 15° to 35° anteversion. Intraoperative radiographic measurements were calculated and final cup position was determined after strict impingement and range-of-motion testing. Postoperative anteroposterior pelvic radiographs were made. Two independent observers remeasured all abduction and anteversion angles. RESULTS: Of the cups, 97.8% were placed within 30° to 50° of abduction, with a mean angle (and standard deviation) of 39.5° ± 4.6°. The 2.2% of cups placed outside the target zone were placed so purposefully on the basis of intraoperative range-of-motion testing and patient factors, and 97.6% of cups were placed between 15° and 35° of anteversion, with a mean angle of 26.6° ± 4.7°. Twenty-eight percent of cups were repositioned on the basis of intraoperative measurements. Subluxation during range-of-motion testing occurred in 3% of hips despite acceptable measurements, necessitating cup repositioning. There was 1 early anterior dislocation. CONCLUSIONS: Placing the acetabular component within a target range is a critical component to minimizing dislocation and polyethylene wear in total hip arthroplasty. Using digital radiography, we positioned the acetabular component in our desired target zone in 97.8% of cases and outside the target zone, purposefully, in 2.2% of cases. When used in conjunction with strict impingement testing, digital radiography allows for predictable cup placement in total hip arthroplasty.

The Effect of Hamstring Tendon Autograft Harvest on the Restoration of Knee Stability in the Setting of Concurrent Anterior Cruciate Ligament and Medial Collateral Ligament Injuries.

BACKGROUND: A hamstring autograft is commonly used in anterior cruciate ligament (ACL) reconstruction (ACLR); however, there is evidence to suggest that the tendons harvested may contribute to medial knee instability. HYPOTHESIS: We tested the hypothesis that the gracilis (G) and semitendinosus (ST) tendons significantly contribute to sagittal, coronal, and/or rotational knee stability in the setting of ACLR with a concurrent partial medial collateral ligament (MCL) injury. STUDY DESIGN: Controlled laboratory study. METHODS: Twelve human cadaveric knees were subject to static forces applied to the tibia including an anterior-directed force as well as varus, valgus, and internal and external rotation moments to quantify laxity at 0°, 30°, 60°, and 90° of flexion. The following ligament conditions were tested on each specimen: (1) ACL intact/MCL intact, (2) ACL deficient/MCL intact, (3) ACL deficient/partial MCL injury, and (4) ACLR/partial MCL injury. To quantify the effect of muscle loads, the quadriceps, semimembranosus, biceps femoris, sartorius (SR), ST, and G muscles were subjected to static loads. The loads on the G, ST, and SR could be added or removed during various test conditions. For each ligament condition, the responses to loading and unloading the G/ST and SR were determined. Three-dimensional positional data of the tibia relative to the femur were recorded to determine tibiofemoral rotations and translations. RESULTS: ACLR restored anterior stability regardless of whether static muscle loads were applied. There was no significant increase in valgus motion after ACL transection. However, when a partial MCL tear was added to the ACL injury, there was a 30% increase in valgus rotation ( P < .05). ACLR restored valgus stability toward that of the intact state when the G/ST muscles were loaded. A load on the SR muscle without a load on the G/ST muscles restored 19% of valgus rotation; however, it was still significantly less stable than the intact state. CONCLUSION: After ACLR in knees with a concurrent partial MCL injury, the absence of loading on the G/ST did not significantly alter anterior stability. Simulated G/ST harvest did lead to increased valgus motion. These results may have important clinical implications and warrant further investigation to better outline the role of the medial hamstrings, particularly among patients with a concomitant ACL and MCL injury. CLINICAL RELEVANCE: A concurrent ACL and MCL injury is a commonly encountered clinical problem. Knowledge regarding the implications of hamstring autograft harvest techniques on joint kinematics may help guide management decisions.

Nationwide Analysis of Femoral Neck Fractures in Elderly Patients: A Receding Tide.

BACKGROUND: Geriatric femoral neck fractures are associated with substantial morbidity and medical cost. We evaluated the incidence and management trends of femoral neck fractures in recent years in the U.S. METHODS: Patient data from 2003 through 2013 were obtained from the Nationwide Inpatient Sample database. Femoral neck fractures in patients ≥65 years old were identified and grouped using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) procedure codes for internal fixation, hemiarthroplasty, or total hip arthroplasty (THA). The nationwide incidence of femoral neck fractures was calculated and presented as an age-adjusted population rate. Univariable methods were used for trend analysis and comparisons between groups. Logistic regression modeling was used to analyze complications. RESULTS: From 2003 to 2013, we identified 808,940 femoral neck fractures in patients ≥65 years old. The national age-adjusted incidence of femoral neck fractures decreased from 242 per 100,000 U.S. adults in 2003 to 146 in 2013. The proportion of fractures managed operatively with THA increased over time (5.9% in 2003 versus 7.4% in 2013; p < 0.001). Concurrently, the use of hemiarthroplasty declined (65.1% versus 63.6%; p < 0.001). In 2013, the median age of the patients treated with THA was significantly younger (77.3 years) compared with that in the hemiarthroplasty and internal fixation groups (83.2 and 82.0 years). The THA group had significantly higher median initial hospital costs ($17,097) compared with the hemiarthroplasty and internal fixation groups ($14,776 and $10,462). CONCLUSIONS: In the last decade, the total number and population rate of femoral neck fractures in the elderly declined significantly. There was a modest but significant increase in the utilization of THA. CLINICAL RELEVANCE: This report identifies the changing trends in clinical practice in the treatment of geriatric femoral neck fractures in the U.S. Treating physicians should be aware of these trends, which include a decreasing national incidence of geriatric femoral neck fractures as well as an increase in the use of THA.