Left-digit bias in surgical decision-making for lumbar spinal stenosis.

BACKGROUND CONTEXT: Left-digit bias is a behavioral heuristic or cognitive "shortcut" in which the leftmost digit of a number, such as patient age, disproportionately influences surgical decisions. PURPOSE: To determine if left-digit bias in patient age influences the decision to perform arthrodesis with instrumentation vs decompression in lumbar spinal stenosis (LSS). DESIGN: Retrospective cohort. PATIENT SAMPLE: Patients with an ICD-10 diagnosis of lumbar stenosis or spondylolisthesis identified in the 2017-2021 National Surgical Quality Improvement Program (NSQIP) database. OUTCOME MEASURES: The primary outcome was the percent of patients who underwent arthrodesis with instrumentation (AwI). Matched age group comparisons without left-digit differences (ie, 76/77 vs 78/79, 80/81 vs 82/83, etc.) were performed to isolate the effect of the heuristic. Secondary outcomes including peri-operative events and complications were also compared within AwI and decompression cohorts. METHODS: Using CPT codes, procedures were classified as either AwI or decompression. Patients were grouped into 6 cohorts based on 2-year age windows (74/75, 76/77, 78/79, 80/81, 82/83, 84/85). The cohorts were propensity matched with neighboring age groups based on the presence of spondylolisthesis, demographics, and comorbidities. The primary comparison was between those aged 78/79 vs 80/81. RESULTS: After matching, the primary cohort consisted of two groups of 1,550 patients (aged 78/79 and 80/81). Patients aged 80/81 were less likely to undergo AwI than patients aged 78/79 (23.5% vs 27.2%, p=.021). AwI procedures occurred at similar rates between age groups with the same left digit. Within the decompression and AwI cohorts, there were no differences in secondary outcomes between patients aged 78/79 and 80/81. CONCLUSIONS: LSS patients aged 80/81 are less likely to undergo AwI than patients aged 78/79, regardless of comorbidities. This was not seen when comparing patients with similar left digits in age. Until objective measures of physiologic capacity are established, left-digit bias may influence clinical decisions.

Intravenous Ketorolac Substantially Reduces Opioid Use and Length of Stay After Lumbar Fusion: A Randomized Controlled Trial.

STUDY DESIGN: A randomized, double-blinded, placebo-controlled trial. OBJECTIVE: To examine the effect of intravenous ketorolac (IV-K) on hospital opioid use compared with IV-placebo (IV-P) and IV acetaminophen (IV-A). SUMMARY OF BACKGROUND DATA: Controlling postoperative pain while minimizing opioid use after lumbar spinal fusion is an important area of study. PATIENTS AND METHODS: Patients aged 18 to 75 years undergoing 1 to 2 level lumbar fusions between April 2016 and December 2019 were included. Patients with chronic opioid use, smokers, and those on systemic glucocorticoids or contraindications to study medications were excluded. A block randomization scheme was used, and study personnel, hospital staff, and subjects were blinded to the assignment. Patients were randomized postoperatively. The IV-K group received 15 mg (age > 65) or 30 mg (age < 65) every six hours (q6h) for 48 hours, IV-A received 1000 mg q6h, and IV-P received normal saline q6h for 48 hours. Demographic and surgical details, opioid use in morphine milliequivalents, opioid-related adverse events, and length of stay (LOS) were recorded. The primary outcome was in-hospital opioid use up to 72 hours. RESULTS: A total of 171 patients were included (58 IV-K, 55 IV-A, and 58 IV-P) in the intent-to-treat (ITT) analysis, with a mean age of 57.1 years. The IV-K group had lower opioid use at 72 hours (173 ± 157 mg) versus IV-A (255 ± 179 mg) and IV-P (299 ± 179 mg; P = 0.000). In terms of opiate use, IV-K was superior to IV-A ( P = 0.025) and IV-P ( P = 0.000) on ITT analysis, although on per-protocol analysis, the difference with IV-A did not reach significance ( P = 0.063). When compared with IV-P, IV-K patients reported significantly lower worst ( P = 0.004), best ( P = 0.001), average ( P = 0.001), and current pain ( P = 0.002) on postoperative day 1, and significantly shorter LOS ( P = 0.009) on ITT analysis. There were no differences in opioid-related adverse events, drain output, clinical outcomes, transfusion rates, or fusion rates. CONCLUSIONS: By reducing opioid use, improving pain control on postoperative day 1, and decreasing LOS without increases in complications or pseudarthrosis, IV-K may be an important component of "enhanced recovery after surgery" protocols.

Preoperative and Postoperative Segmental and Overall Range of Motion in Patients Undergoing Lumbar Spinal Fusion Using HA-Infused PEEK and HA-Treated Titanium Alloy Interbody Cages.

STUDY DESIGN: Retrospective observational radiographic analysis. OBJECTIVE: Determine how single level lumbar interbody fusion (LIF) alters segmental range of motion (ROM) at adjacent levels and decreases overall ROM. METHODS: This study included 54 patients who underwent single-level anterior (ALIF, 39%), thoraco-LIF (TLIF, 26%), posterior LIF (PLIF, 22%), or lateral LIF (LLIF, 13%) (L2-3/L3-4/L4-5/L5-S1: 4%/13%/35%/48%). Segmental ROM from L1-2 to L5-S1 and the overall lumbar ROM (L1-S1) were assessed from preoperative and postoperative flexion-extension radiographs. K-means cluster analysis was used to identify ROM subgroups. RESULTS: The overall L1-S1 ROM decreased 14% (25.5 ± 20.4° to 22.0 ± 17.2°, P = .104) postoperatively. ROM at the fusion level decreased 77% (4.8 ± 5.0° to 1.1 ± 1.1°, P < .001). Caudal adjacent segment ROM decreased 12% (5.2 ± 5.7° to 4.6 ± 4.4°, P = .345) and cranially ROM increased 34% (4.3 ± 5.0° to 5.7 ± 5.7°, P = .05). K-cluster analysis identified 3 distinct clusters (P < .05). Cluster 1 lost more ROM and had less improvement in patient-reported outcomes measures (PROMs) than average. Cluster 2 had less ROM loss than average with worse PROMs improvement. Cluster 3 did not have changes in ROM and better improvement in PROMs than average. Successful fusion was verified in 96% of all instrumented segments with >6 months follow-up (ROM <4°). CONCLUSION: Following single-level L IF, patients should expect a loss of 3.3°, or 14% of overall lumbar motion with increases in ROM of the cranial segment. However, specific clusters of patients exist that experience different relative changes in ROM and PROMs.

Why Didn't You Walk Yesterday? Factors Associated With Slow Early Recovery After Adult Spinal Deformity Surgery.

STUDY DESIGN: This is a retrospective case-control study. OBJECTIVES: The objectives of this study are to identify (1) risk factors for delayed ambulation following adult spinal deformity (ASD) surgery and (2) complications associated with delayed ambulation. METHODS: One-hundred and ninety-one patients with ASD who underwent posterior-only fusion (≥5 levels, LIV pelvis) were reviewed. Patients who ambulated with physical therapy (PT) on POD2 or later (LateAmb, n = 49) were propensity matched 1:1 to patients who ambulated on POD0-1 (NmlAmb, n = 49) based on the extent of fusion and surgical invasiveness score (ASD-S). Risk factors, as well as inpatient medical complications were compared. Logistic regressions were used to identify risk factors for late ambulation. RESULTS: Of the patients who did not ambulate on POD0-1, 32% declined participation secondary to pain or dizziness/fatigue, while 68% were restricted from participation by PT/nursing due to fatigue, inability to follow commands, nausea/dizziness, pain, or hypotension. Logistic regression showed that intraoperative estimated blood loss (EBL) >2L (OR = 5.57 [1.51-20.55], P = .010) was independently associated with an increased risk of delayed ambulation, with a 1.25 times higher risk for every 250 mL increase in EBL (P = .014). Modified 5-Item Frailty Index (mFI-5) was also independently associated with delayed ambulation (OR = 2.53 [1.14-5.63], P = .023). LateAmb demonstrated a higher hospital LOS (8.4 ± 4.0 vs 6.2 ± 2.6, P < .001). The LateAmb group trended toward an increase in medical complications on POD3+ (14.3% vs 26.5%, P = .210). CONCLUSIONS: EBL demonstrates a dose-response relationship with risk for delayed ambulation. Delayed ambulation increases LOS and may impact medical complications.

The Association of Lumbar Plexus Lengthening with Neurologic Deficit After Adult Spinal Deformity Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: This study aimed to evaluate the association between nerve lengthening after adult deformity correction and motor deficits dervied from the upper lumbar plexus or femoral nerve. SUMMARY OF BACKGROUND DATA: Adult spinal deformity (ASD) surgery is associated with high rates of neurological deficits. Certain postoperative deficits may be related to lengthening of the upper lumbar plexus (ULP) and/or femoral nerve (FN) after correction of lumbar deformity. METHODS: Patients with ASD who underwent posterior-only corrective surgery from the sacrum to L3 or above were included. The length of each lumbar nerve root (NR) was calculated geometrically using the distance from the foramen to the midpoint between the anterosuperior iliac crest and pubic symphysis on AP and lateral radiographs. The mean lengths of the L1-3 and L2-4 NRs were used to define the lengths of the ULP and FN, respectively. Pre- to postoperative changes in nerve length were calculated. Neurological examination was performed at discharge. Proximal weakness (PW) was defined as the presence of weakness compared to baseline in either hip flexors or knee extensors. Multiple linear regression analysis was used for estimating the postoperative lengthening according to the magnitude of preoperative curvature and postoperative correction angles. RESULTS: A total of 202 sides were analyzed in 101 patients, and PW was present on 15 (7.4%) sides in 10 patients. Excluding the 10 cases with three-column osteotomies, those with PW had a significantly higher rate of pure sagittal deformity (P<.001) and greater nerve lengthening than those without PW (ULP 24 vs 15 mm, P=0.02; FN 18 vs 11 mm, P=0.05). No patient had advanced imaging showing neural compression, and complete recovery of PW occurred in 8 patients at 1-year follow-up. CONCLUSIONS: After ASD surgery, lengthening of the ULP was associated with PW. In preoperative planning, surgeons must consider how the type of correction may influence the risk for nerve lengthening, which may contribute to postoperative neurologic deficit. LEVEL OF EVIDENCE: 3.

Improving Racial and Ethnic Disparities in Outpatient Anterior Cervical Discectomy and Fusion Driven by Increasing Utilization of Ambulatory Surgical Centers in New York State.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The purpose of this study was to assess trends in disparities in utilization of hospital outpatient departments (HOPDs) and ambulatory surgical centers (ASCs) for outpatient ACDF (OP-ACDF) between White, Black, Hispanic, and Asian/Pacific Islander patients from 2015 to 2018 in New York State. SUMMARY OF BACKGROUND DATA: Racial and ethnic disparities within the field of spine surgery have been thoroughly documented. To date, it remains unknown how these disparities have evolved in the outpatient setting alongside the rapid emergence of ASCs and whether restrictive patterns of access to these outpatient centers exist by race and ethnicity. MATERIALS AND METHODS: We conducted a retrospective review from 2015 to 2018 using the Healthcare Cost and Utilization Project (HCUP) New York State Ambulatory Database. Differences in utilization rates for OP-ACDF were assessed and trended over time by race and ethnicity for both HOPDs and freestanding ASCs. Poisson regression was used to evaluate the association between utilization rates for OP-ACDF and race/ethnicity. RESULTS: Between 2015 and 2018, Black, Hispanic, and Asian patients were less likely to undergo OP-ACDF compared with White patients in New York State. However, the magnitude of these disparities lessened over time, as Black, Hispanic, and Asian patients had greater relative increases in utilization of HOPDs and ASCs for ACDF when compared with White patients ( Ptrend <0.001). The magnitude of the increase in freestanding ASC utilization was such that minority patients had higher ACDF utilization rates in freestanding ASCs by 2018 ( P <0.001). CONCLUSIONS: We found evidence of improving racial disparities in the relative utilization of outpatient ACDF in New York State. The increase in access to outpatient ACDF appeared to be driven by an increasing number of patients undergoing ACDF in freestanding ASCs in large metropolitan areas. These improving disparities are encouraging and contrast previously documented inequalities in inpatient spine surgery. LEVEL OF EVIDENCE: III.

Short Term Outcomes (Average Follow-Up of 2.4 Years) of a Constrained Acetabular Liner in Primary and Revision Total Hip Arthroplasty.

BACKGROUND: As instability continues to be a burden post-total hip arthroplasty (THA), there has been a controversial discussion on the ideal implant choice. We report the outcomes of a modern constrained acetabular liner (CAL) system in primary and revision THA at an average follow-up of 2.4 years. METHODS: We performed a retrospective study of all patients undergoing primary and revision hip arthroplasty and being implanted with the modern CAL system from 2013 to 2021. We identified 31 hips, of which 13 underwent primary THA and the remaining 18 underwent revision THA for instability. RESULTS: Of those implanted with CAL primarily, 3 had concomitant abductor tear repair and gluteus maximus transfer, 5 had Parkinson's disease, 2 had inclusion body myositis, 1 had amyotrophic lateral sclerosis, and the remaining two were over 94 years of age. All patients implanted with the CAL had active instability post-primary THA and underwent only liner and head exchange without revision of the acetabular or femoral components. At an average follow-up of 2.4 years (ranging from 9 months to 5 years and 4 months), we had 1 case (3.2%) of dislocation post-CAL implantation. None of the patients undergoing surgery with CAL for active instability had a redislocation. CONCLUSION: In conclusion, a CAL provides excellent stability in both primary THA in high-risk individuals and revision THA in cases of active instability. There were no dislocations when using a CAL to treat active instability post-THA.

Small residual fracture gaps delay time to union in length stable femur fractures treated with intrameduallary fixation.

OBJECTIVES: The purpose of this study was to investigate whether residual fracture gapping and translation at time of intramedullary nail (IMN) fixation for diaphyseal femur fractures were associated with delayed healing or nonunion. DESIGN: Retrospective cohort study SETTING: Level 1 trauma hospital, quaternary referral center PATIENTS/PARTICIPANTS/INTERVENTION: Length stable Winquist type 1 and 2 diaphyseal femur fractures treated with IMN at a single Level I trauma center were retrospectively reviewed. MAIN OUTCOME MEASURE: The largest fracture gap and translation were evaluated on immediate anteroposterior (AP) and lateral postoperative radiographs. Radiographic healing was assessed using Radiographic Union Score in Femur (RUSF) scores at each follow-up. Radiographic union was defined as a RUSF score ≥8 and consolidation of at least 3 cortices. ANOVA and student's t-tests were used to evaluate the influence of fracture gap parameters on time to union (TTU) and nonunion rate. Patients were stratified to measured average gap and translation distances <1mm, 1-3mm and >3mm for portions of the analysis. RESULTS: Sixty-six patients who underwent IMN with adequate follow-up were identified. A total of 93.9% of patients achieved union at an average of 2.8 months. Fractures with average AP/lateral gaps of <1mm, 1-2.9 mm, and >3mm had an average TTU of 70.1, 91.7, and 111.9 days respectively; fractures with larger residual gap sizes had a significantly longer TTU (p=0.009). Fractures with an average gap of 1-2.9mm and >3 mm had a significantly higher nonunion rate (1.5% and 4.5% respectively) compared to 0% nonunion in the <1 mm group (p=0.003). CONCLUSION: Residual gapping following intramedullary fixation of length stable diaphyseal femur fractures is associated with a significant increase in likelihood of nonunion. SUMMARY: Residual displacement of length stable femoral shaft fractures following intramedullary nailing can have a significantly negative impact on fracture healing. An average 3 mm AP/lateral residual fracture gap or a total of 6 mm of the AP + lateral fracture gap appeared to be a critical gap size with increased rates of nonunion and time to union. Therefore, we suggest minimizing the sum of the residual AP and lateral fracture gap to less than a total of 6 mm.

Implant Malalignment may be a Risk Factor for Poor Patient-Reported Outcomes Measures (PROMs) Following Total Knee Arthroplasty (TKA).

BACKGROUND: Implant malalignment may be a risk factor for poor patient-reported outcomes measures (PROMs) following total knee arthroplasty (TKA). METHODS: Postoperative surveys were administered to assess PROMs regarding satisfaction, pain, and function in 262 patients who underwent surgery at 4 centers in the U.S. and U.K (average age, 67.2) at a mean 5.5 years after primary TKA. Postoperative distal femoral angle (DFA), proximal tibial angle (PTA), and posterior tibial slope angle (PSA) were radiographically measured, and outliers were recorded. PROMs were compared between patients with aligned versus malaligned knees using univariate analysis. RESULTS: Patients with DFA, PTA, and PSA outliers were more likely to experience similar or decreased activity levels postoperatively than patients with no alignment outliers, as were patients with 1 or 2 outliers of any kind (P < .05). Patients with DFA, PTA, and PSA outliers were significantly more likely to be dissatisfied with their ability to perform activities of daily living (ADLs), as were patients with 1 or 2 outliers of any kind (P < .05). Patients with DFA and PSA outliers were more likely to be dissatisfied with their degree of pain relief, as were patients with 2 outliers of any kind (P < .05). Finally, patients with DFA and PSA outliers, as well as those with 1 outlier of any kind, were more likely to be dissatisfied with their overall knee function (P < .05). CONCLUSION: DFA, PTA, and PSA outliers represent a significant risk factor for decreased satisfaction with activities of daily living(ADLs), pain relief, and knee function, as well as decreased activity levels. LEVEL OF EVIDENCE: Level III.

Outcomes Following Repeat Ankle Arthroscopy and Microfracture for Osteochondral Lesions of the Talus.

BACKGROUND: The management of symptomatic osteochondral lesions of the talus (OLTs) previously treated with arthroscopy is controversial. Minimal data exist on the role for repeat arthroscopy. Here, we describe our experience with repeat arthroscopy and microfracture for symptomatic OLTs. METHODS: Our database was queried over an 8-year period to identify patients undergoing repeat arthroscopy and microfracture as treatment for symptomatic OLTs. Phone surveys were conducted to assess residual pain, patient satisfaction, and need for subsequent surgery. We compared patient outcomes based on the size of their OLT (small lesions ≤150 mm2, large >150 mm2) and the presence or absence of subchondral cysts. RESULTS: We identified 14 patients who underwent repeat arthroscopy and microfracture for symptomatic OLTs. Patients reported reasonable satisfaction (7.6 ± 3.5 out of 10) but moderate residual pain (4.7 ± 3.4 out of 10) at midterm follow-up (5.1 ± 2.9 years). In total, 21% (3/14) of patients had undergone subsequent surgery. Patients with small (n = 5) and large OLTs (n = 9) had similar postoperative pain scores (4.2 ± 4.1 vs 4.9 ± 3.2) and postoperative satisfaction levels (6.4 ± 4.9 vs 8.3 ± 2.5). CONCLUSION: At midterm follow-up, repeat arthroscopy for symptomatic OLTs demonstrated reasonable satisfaction but moderate residual pain. Lesion size or presence of subchondral cysts did not affect outcome, but our sample size was likely too small to detect statistically significant differences. These data show that repeat ankle arthroscopy can be performed safely with modest outcomes, and we hope that this report aids in managing patient expectations.Level of Evidence: Level IV Case Series.

The Impact of Corticosteroid Injection Timing on Infection Rates Following Spine Surgery: A Systematic Review and Meta-Analysis.

STUDY DESIGN/SETTING: Systematic review/meta-analysis. OBJECTIVES: The objective of this review was to assess how the risk of infection following lumbar spine surgery varies as a function of the timing of preoperative corticosteroid spinal injections (CSIs). METHODS: A systematic review and meta-analysis was performed in accordance with the PRISMA guidelines. PubMed and EMBASE databases were searched and data was pooled for meta-analysis. RESULTS: Six studies were identified for inclusion. Two (33.3%) demonstrated a significant relationship between the timing of preoperative CSIs and the risk of postoperative infection, while 4 (66.7%) demonstrated no impact. A total of 2.5% (110/4,448) of patients who underwent CSI <1 month before surgery experienced a postoperative infection, as compared to 1.2% (1,466/120, 943) of controls, which was statistically significant (RR = 1.986 95% CI 1.202-3.282 P = 0.007). A total of 1.6% (25/1,600) of patients who underwent CSI 0-3 months before surgery experienced a postoperative infection, as compared to 1.6% (201/12, 845) of controls (RR = 0.887 95% CI 0.586-1.341, P = 0.569). A total of 1.1% (199/17 870) of patients who underwent CSI 3-6 months before surgery experienced a postoperative infection, as compared to 1.3% (1,382/102, 572) of controls (RR = 1.053 95% CI 0.704-1.575, P = 0.802). Differences in infection risk for 0-3 months and 3-6 months were not statistically significant. CONCLUSIONS: CSIs <1 month prior to lumbar spine surgery are a significant risk factor for infection, while CSIs beyond that point showed no such association. Surgeons should consider avoiding CSIs <1 month of the use of CSIs of the spine.

Intra-articular administration of vancomycin and tobramycin during primary cementless total knee arthroplasty : determination of intra-articular and serum elution profiles.

AIMS: Intra-articular administration of antibiotics during primary total knee arthroplasty (TKA) may represent a safe, cost-effective strategy to reduce the risk of acute periprosthetic joint infection (PJI). Vancomycin with an aminoglycoside provides antimicrobial cover for most organisms isolated from acute PJI after TKA. However, the intra-articular doses required to achieve sustained therapeutic intra-articular levels while remaining below toxic serum levels is unknown. The purpose of this study is to determine the intra-articular and serum levels of vancomycin and tobramycin over the first 24 hours postoperatively after intra-articular administration in primary cementless TKA. METHODS: A prospective cohort study was performed. Patients were excluded if they had poor renal function, known allergic reaction to vancomycin or tobramycin, received intravenous vancomycin, or were scheduled for same-day discharge. All patients received 600 mg tobramycin and 1 g of vancomycin powder suspended in 25 cc of normal saline and injected into the joint after closure of the arthrotomy. Serum from peripheral venous blood and drain fluid samples were collected at one, four, and 24 hours postoperatively. All concentrations are reported in µg per ml. RESULTS: A total of 22 patients were included in final analysis. At one, four, and 24 hours postoperatively, mean (95% confidence interval (CI)) serum concentrations were 2.4 (0.7 to 4.1), 5.0 (3.1 to 6.9), and 4.8 (2.8 to 6.9) for vancomycin and 4.9 (3.4 to 6.3), 7.0 (5.8 to 8.2), and 1.3 (0.8 to 1.8) for tobramycin; intra-articular concentrations were 1,900.6 (1,492.5 to 2,308.8), 717.9 (485.5 to 950.3), and 162.2 (20.5 to 304.0) for vancomycin and 2,105.3 (1,389.9 to 2,820.6), 403.2 (266.6 to 539.7), and 98.8 (0 to 206.5) for tobramycin. CONCLUSION: Intra-articular administration of 1 g of vancomycin and 600 mg of tobramycin as a solution after closure of the arthrotomy in primary cementless TKA achieves therapeutic intra-articular concentrations over the first 24 hours postoperatively and does not reach sustained toxic levels in peripheral blood. Cite this article: Bone Joint J 2021;103-B(11):1702-1708.

Clinical impact of component placement in manually instrumented total knee arthroplasty : a systematic review.

AIMS: The goal of the current systematic review was to assess the impact of implant placement accuracy on outcomes following total knee arthroplasty (TKA). METHODS: A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using the Ovid Medline, Embase, Cochrane Central, and Web of Science databases in order to assess the impact of the patient-reported outcomes measures (PROMs) and implant placement accuracy on outcomes following TKA. Studies assessing the impact of implant alignment, rotation, size, overhang, or condylar offset were included. Study quality was assessed, evidence was graded (one-star: no evidence, two-star: limited evidence, three-star: moderate evidence, four-star: strong evidence), and recommendations were made based on the available evidence. RESULTS: A total of 49 studies were identified for inclusion. With respect to PROMs, there was two-star evidence in support of mechanical axis alignment (MAA), femorotibial angle (FTA), femoral coronal angle (FCA), tibial coronal angle (TCA), femoral sagittal angle (FSA), femoral rotation, tibial and combined rotation/mismatch, and implant size/overhang or offset on PROMs, and one-star evidence in support of tibial sagittal angle (TSA), impacting PROMs. With respect to survival, there was three- to four-star evidence in support FTA, FCA, TCA, and TSA, moderate evidence in support of femoral rotation, tibial and combined rotation/mismatch, and limited evidence in support of MAA, FSA, and implant size/overhang or offset impacting survival. CONCLUSION: Overall, there is limited evidence to suggest that PROMs are impacted by the accuracy of implant placement, and malalignment does not appear to be a significant driver of the observed high rates of patient dissatisfaction following TKA. However, FTA, FCA, TCA, TSA, and implant rotation demonstrate a moderate-strong relationship with implant survival. Efforts should be made to improve the accuracy of these parameters in order to improve TKA survival. Cite this article: Bone Joint J 2021;103-B(9):1449-1456.

The Impact of Psychological Factors and Their Treatment on the Results of Total Knee Arthroplasty.

➤: There is a growing body of evidence implicating psychosocial factors, including anxiety, depression, kinesiophobia, central sensitization, and pain catastrophizing, as negative prognostic factors following total knee arthroplasty (TKA). ➤: Symptoms of anxiety and depression likely represent risk factors for negative outcomes in patients undergoing TKA. However, few studies have assessed the impact of preoperative interventions for these conditions on postoperative outcomes. ➤: The Tampa Scale of Kinesiophobia and the Central Sensitization Inventory have demonstrated value in the diagnosis of kinesiophobia and central sensitization. Higher preoperative indices of kinesiophobia and central sensitization predict worse patient-reported outcomes postoperatively. ➤: Although evidence is limited, cognitive-behavioral therapy for kinesiophobia and duloxetine for central sensitization may help to diminish the negative impact of these preoperative comorbidities. It is important to note, however, that outside the realm of TKA, cognitive-behavioral therapy has been recognized as a more effective treatment for central sensitization than medical treatment. ➤: Awareness of these issues will allow surgeons to better prepare patients regarding postoperative expectations in the setting of a comorbid psychosocial risk factor. Further research into the role of preoperative assessment and possible treatment of these conditions in patients undergoing TKA is warranted.

Infographics Are More Effective at Increasing Social Media Attention in Comparison With Original Research Articles: An Altmetrics-Based Analysis.

PURPOSE: To compare social media attention and citation rates between infographics (visual abstracts) and original research articles. METHODS: All infographics in 2019 from electronic versions of Arthroscopy were matched by topic to articles in the "Original Research" section of the journal in a 4:1 ratio within the same year. The primary outcome was the Altmetric Attention Score (AAS), a cumulative measure of social media attention from various platforms such as Twitter and Facebook. Secondary outcomes included citation rates, article characteristics, and number of shares on social media platforms. Independent t tests and χ2 analyses were used to compare primary and secondary outcomes between infographics and control articles. Multivariate linear regression analysis was performed to determine the association between article type and social media attention while controlling for bibliometric characteristics. RESULTS: A total of 60 matched research articles (n = 48, 80.0%) and infographics (n = 12, 20.0%) published in 2019 in Arthroscopy were included. The mean AAS among all infographics was 29.75 ± 32.84 (range, 3-118), whereas the mean AAS among all control research articles was 5.75 ± 8.90 (range, 0-41), representing a statistically significant difference (P < .001). Infographics had significantly more Twitter mentions (100% vs 70.8%, P < .001) and Facebook mentions (75% vs. 6.2%, P < .001) compared with original articles. Multivariate linear regression analysis demonstrated a statistically significant and positive association between AAS and article type, with an additional mean increase in the AAS of 33.7 (95% confidence interval 11.6-50.6; P = .003) for every infographic article compared with an original research article. The mean citation rate among all infographics was 2.4 ± 2.4 (range, 0-7), whereas the mean citation rate among all control research articles was 2.2 ± 4.0 (range, 0-27), which was not a significant difference (P = .69). CONCLUSIONS: Infographics resulted in significantly greater AAS and social media attention in comparison with original research articles of similar topics. We recommend the routine creation of infographics by journals to increase the social media attention that their research and chosen topics of interest receive. However, viewers of infographics should read them out of interest but turn their attention toward the original article or a source of more detailed information before making changes in clinical decision-making or practice, as they can be oversimplified. CLINICAL RELEVANCE: Infographics are an increasingly used by journals as a form of depicting research findings from select studies. By producing infographics, journals may increase the amount of social media attention received for a particular study or topic of interest.

Cost Comparison of Botulinum Toxin Injections Versus Surgical Treatment in Pediatric Patients With Cerebral Palsy: A Markov Model.

PURPOSE: The purpose of this study was to compare the cost-effectiveness of surgical release to botulinum toxin injections in the treatment of upper-extremity (UE) cerebral palsy (CP). METHODS: A Markov transition-state model was developed to assess the direct and indirect costs as well as accumulated quality-adjusted life-years associated with surgery (surgery group) and continuous botulinum toxin injections (botulinum group) for the treatment of UE CP in children aged 7 to 12 years. Direct medical costs were obtained from institutional billing departments. The number of parental missed workdays associated with each treatment was estimated and previously published regressions were used to calculate indirect costs associated with missed work. Total costs, cost-effectiveness, and incremental cost-effectiveness ratios were calculated. Incremental cost-effectiveness ratios and willingness to pay thresholds were used to make decisions regarding society's willingness to pay for the incremental cost of each treatment given the incremental benefit. RESULTS: The surgery group demonstrated lower direct, indirect, and total costs compared with the botulinum group. Direct costs were $29,250.50 for the surgery group and $50,596.00 for the botulinum group. Indirect costs were $9,467.46 for the surgery group and $44,428.60 for the botulinum group. Total costs were $38,717.96 for the surgery group and $95,024.60 for the botulinum group, a difference of $56,306.64. The incremental cost-effectiveness ratio was -$42,019.88, indicating that surgery is a less costly and more effective treatment and that botulinum injections fall outside the societal willingness to pay threshold. Excluding indirect costs associated with parental missed work during home occupational therapy did not have a significant impact on the model. CONCLUSIONS: Surgery is associated with lower direct, indirect, and total costs, as well as a greater number of accumulated quality-adjusted life-years. Surgery provides a greater benefit at a lower cost, which suggests that botulinum injections should be used sparingly in this population. Treatment with surgery could represent savings of $5.6 to $11.3 billion annually in the United States. TYPE OF STUDY/LEVEL OF EVIDENCE: Economic/Decision Analysis II.

Radiological outcomes following manual and robotic-assisted unicompartmental knee arthroplasty.

AIMS: The purpose of this study was to compare the radiological outcomes of manual versus robotic-assisted medial unicompartmental knee arthroplasty (UKA). METHODS: Postoperative radiological outcomes from 86 consecutive robotic-assisted UKAs (RAUKA group) from a single academic centre were retrospectively reviewed and compared to 253 manual UKAs (MUKA group) drawn from a prior study at our institution. Femoral coronal and sagittal angles (FCA, FSA), tibial coronal and sagittal angles (TCA, TSA), and implant overhang were radiologically measured to identify outliers. RESULTS: When assessing the accuracy of RAUKAs, 91.6% of all alignment measurements and 99.2% of all overhang measurements were within the target range. All alignment and overhang targets were simultaneously met in 68.6% of RAUKAs. When comparing radiological outcomes between the RAUKA and MUKA groups, statistically significant differences were identified for combined outliers in FCA (2.3% vs 12.6%; p = 0.006), FSA (17.4% vs 50.2%; p < 0.001), TCA (5.8% vs 41.5%; p < 0.001), and TSA (8.1% vs 18.6%; p = 0.023), as well as anterior (0.0% vs 4.7%; p = 0.042), posterior (1.2% vs 13.4%; p = 0.001), and medial (1.2% vs 14.2%; p < 0.001) overhang outliers. CONCLUSION: Robotic system navigation decreases alignment and overhang outliers compared to manual UKA. Given the association between component placement errors and revision in UKA, this strong significant improvement in accuracy may improve implant survival. Level of Evidence: III Cite this article: Bone Jt Open 2021;2-3:191-197.

Hip resurfacing arthroplasty and total hip arthroplasty in the same patient: which do they prefer?

INTRODUCTION: Hip resurfacing arthroplasty (HRA) is an alternative to conventional total hip arthroplasty (THA) with potential advantages of preserving femoral bone stock and the ability to participate in higher impact activities. This study compares outcomes, satisfaction and preference in patients who underwent HRA in 1 hip and THA on the contralateral side. METHODS: 62 Patients with an HRA in 1 hip and a contralateral THA were retrospectively identified at 3 centres, consisting of 38 males and 24 females with 53 patients (85.5%) undergoing HRA first. A survey regarding satisfaction and preference for each procedure and outcome scores were obtained. RESULTS: Patients were younger (51.5 vs. 56.6 years, p = 0.002) and had longer follow-up on the HRA hip (11.0 vs. 6.0 years, p < 0.001). HRA was associated with larger increase in Harris Hip Score from preoperative to final follow-up (35.8 vs. 30.6, p = 0.035). 18 Patients (29.0%) preferred HRA, 19 (30.6%) preferred THA and 25 (40.3%) had no preference (p = 0.844). When asked what they would choose if they could only have 1 surgery again, 41 (66.1%, p < 0.001) picked HRA. Overall satisfaction (p = 0.504), willingness to live with their HRA versus THA for the rest of their life (p = 0.295) and recommendation to others (p = 0.097) were similar. CONCLUSIONS: Although HRA is associated with risks related to metal-on-metal bearings, it showed greater increase in patient-reported outcomes and a small subjective preference amongst patients who have undergone both conventional and resurfacing arthroplasty.

Prior Manipulation under Anesthesia is a Predictor of Contralateral Manipulation in Staged Bilateral Total Knee Arthroplasty.

BACKGROUND: There are many risk factors for arthrofibrosis and manipulation under anesthesia (MUA) following total knee arthroplasty (TKA). However, no study has elucidated whether a history of MUA increases the risk of contralateral MUA in patients undergoing staged bilateral TKA. METHODS: A retrospective review of an institutional database of TKAs was performed. All patients aged ≥18 years who underwent primary staged bilateral TKAs were screened for inclusion. Staged bilateral TKAs were viewed as 2 distinct events based on the temporal order in which they occurred: TKA#1 (occurred first) and TKA#2 (occurred second). Following TKA#1, patients were split into 2 groups: those who underwent MUA (Group MANIP) and those who did not (Group NO MANIP). The subsequent risk of undergoing MUA following TKA#2 was then assessed and compared between the 2 groups. Chi-squared tests were used for comparison. RESULTS: A total of 5,330 patients who underwent primary uncomplicated staged bilateral TKAs (10,660 knees) during the study period were identified. Overall, 2.1% of patients underwent MUA following TKA#1 and 1.9% of patients underwent MUA following TKA#2. In the MANIP group, 21.4% of patients underwent MUA following TKA#2, while only 1.5% underwent MUA in the NO MANIP group. This 14.3-fold increase in the risk of MUA in the MANIP group following TKA#2 was statistically significant (21.4% vs 1.5%, absolute risk reduction = 19.9%, relative risk reduction = 93.0%, P < .0001). CONCLUSION: Patients who undergo MUA during the first TKA of a staged bilateral TKA are 14.3 times more likely to undergo a subsequent MUA than those who did not undergo MUA following their first TKA.

Pelvic rotation after total hip arthroplasty is dynamic and variable.

AIMS: The aims of this study were to determine the change in the sagittal alignment of the pelvis and the associated impact on acetabular component position at one-year follow-up after total hip arthroplasty (THA). METHODS: This study represents the one-year follow-up of a previous short-term study at our institution. Using the patient population from our prior study, the radiological pelvic ratio was assessed in 91 patients undergoing THA, of whom 50 were available for follow-up of at least one year (median 1.5; interquartile range (IQR) 1.1 to 2.0). Anteroposterior radiographs of the pelvis were obtained in the standing position preoperatively and at one year postoperatively. Pelvic ratio was defined as the ratio between the vertical distance from the inferior sacroiliac (SI) joints to the superior pubic symphysis and the horizontal distance between the inferior SI joints. Apparent acetabular component position changes were determined from the change in pelvic ratio. A change of at least 5° was considered clinically meaningful. RESULTS: Pelvic ratio decreased (posterior tilt) in 54.0% (27) of cases, did not change significantly in 34.0% (17) of cases, and increased (anterior tilt) in 12.0% (6) of cases when comparing preoperative to one-year postoperative radiographs. This would correspond with 5° to 10° of abduction error in 22.0% of cases and > 10° of error in 6.0%. Likewise, this would correspond with 5° to 10° of version error in 22.0% of cases and > 10° of error in 44.0%. CONCLUSION: Pelvic sagittal alignment is dynamic and variable after THA, and these changes persist to the one-year postoperative period, altering the orientation of the acetabular component. Surgeons who individualize the acetabular component placement based on preoperative functional radiographs should consider that the rotation of the pelvis (and thus the component version and inclination) changes one year postoperatively. Cite this article: Bone Joint J 2020;102-B(7 Supple B):47-51.