Comparison of Early Complication Rates After High Tibial Osteotomy Versus Unicompartmental Knee Arthroplasty for Knee Osteoarthritis.

Background: Although both high tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) can be utilized to treat unicompartmental osteoarthritis (OA) in select patients, the early complication rates between the 2 procedures are not well understood. Understanding of the complication profiles for both procedures would help clinicians counsel patients with unicompartmental knee OA who may be eligible for either treatment option. Purpose: To compare the 30-day complication rates after HTO versus UKA for the treatment of knee OA using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Study Design: Cohort study; Level of evidence, 3. Methods: NSQIP registries between 2006 and 2019 were queried using Current Procedural Terminology codes to identify patients undergoing HTO and UKA for knee OA. Patients >60 years of age were excluded. Patient demographics, preoperative comorbidities, and intraoperative data were collected. Postoperative 30-day complications, including venous thromboembolism (VTE), urinary tract infection (UTI), transfusion, surgical-site infection (SSI), and reoperations were recorded. Complication rates between treatment groups were compared using a multivariate logistic regression model adjusted for sex, age, body mass index, steroid use, respiratory status (smoking/dyspnea/chronic obstructive pulmonary disease), diabetes, and hypertension. Results: A total of 156 patients treated with HTO and 4755 patients treated with UKA for knee OA were identified. Mean patient ages were 46 years for the HTO group and 53.4 years for the UKA group. Operative time was significantly longer in the HTO group versus the UKA group (112 minutes vs 90 minutes; P < .001). Multivariate analyses found no significant differences in VTE (1.3% vs 0.6%), UTI (0.6% vs 0.3%), transfusion (0.6% vs 0.2%), deep SSI (0.6% vs 0.1%), and reoperation (1.3% vs 1%) rates between HTO and UKA groups. The HTO group had a higher rate of superficial SSI compared with the UKA group (2.6% vs 0.6%; P = .006) (adjusted odds ratio, 4.2; 95% CI, 1.4-12.5; P = .01). Conclusion: There were no differences in 30-day VTE, UTI, transfusion, deep SSI, and reoperation rates for HTO versus UKA in the treatment of knee OA. HTO was associated with a higher rate of superficial SSI compared with UKA. These findings serve to guide clinicians in counseling patients regarding the early risks after HTO and UKA.

Characterization of the Age-Related Differences in Porcine Acetabulum and Femoral Head Articular Cartilage.

OBJECTIVE: The use of porcine animal models for cartilage injury has increased recently due to their similarity with humans with regard to cartilage thickness, limited intrinsic healing of chondral defects, and joint loading biomechanics. However, variations in the mechanical and biochemical properties of porcine hip articular cartilage among various tissue ages and weightbearing (WB) regions are still unknown. This study's aim was to characterize the mechanical and biochemical properties of porcine hip articular cartilage across various ages and WB regions. METHODS: Articular cartilage explants were harvested from WB and non-weightbearing (NWB) surfaces of the femoral head and acetabulum of domesticated pigs (Sus scrofa domesticus) at fetal (gestational age: 80 days), juvenile (6 months), and adult (2 years) ages. Explants underwent compressive stress-relaxation mechanical testing, biochemical analysis for total collagen and glycosaminoglycan (GAG) content, and histological staining. RESULTS: Juvenile animals consistently had the highest mechanical properties, with 2.2- to 7.6-time increases in relaxation modulus, 1.3- to 2.3-time increases in instantaneous modulus, and 4.1- to 14.2-time increases in viscosity compared with fetal cartilage. Mechanical properties did not significantly differ between the WB and NWB regions. Collagen content was highest in the NWB regions of the juvenile acetabulum (65.3%/dry weight [DW]) and femoral head (75.4%/DW) cartilages. GAG content was highest in the WB region of the juvenile acetabulum (23.7%/DW) and the WB region of the fetal femoral head (27.5%/DW) cartilages. Histological staining for GAG and total collagen content followed the trends from the quantitative biochemical assays. CONCLUSION: This study provides a benchmark for the development and validation of preclinical porcine models for hip cartilage pathologies.

In Vitro Effects of Triamcinolone and Methylprednisolone on the Viability and Mechanics of Native Articular Cartilage.

BACKGROUND: The chondrotoxic effects of methylprednisolone acetate (MP) and triamcinolone acetonide (TA) have been well described. However, the mechanical effects of these commonly used steroids on native cartilage are largely unknown. PURPOSE: To investigate the in vitro effects of a single 1-hour MP or TA exposure on the viability, mechanics, and biochemical content of native articular cartilage explants. STUDY DESIGN: Controlled laboratory study. METHODS: Articular cartilage explants (n = 6 per group) were harvested from the femoral condyles of bovine stifles. Explants were exposed to chondrogenic medium containing a clinical dose of MP or TA for 1 hour, followed by fresh medium wash and exchange. Explants in the control group underwent the same treatment with chondrogenic medium alone. At 24 hours after treatment, samples were assessed for viability (live/dead), mechanical properties (creep indentation and Instron tensile testing), biochemical (collagen and glycosaminoglycan) content, and pyridinoline crosslinking via mass spectrometry. RESULTS: Mean cell viability was significantly decreased in native explants exposed to MP (35.5%) compared with the control (49.8%; P < .001) and TA (45.7%; P = .01) specimens. Significant decreases were seen in the mechanical properties of steroid-treated native explants when compared with controls, with decreases in aggregate modulus (646.3 vs 312.8 kPa [MP] and 257.0 kPa [TA]; P < .001), shear modulus (370.1 vs 191.2 kPa [MP] and 157.4 kPa [TA]; P < .001), and ultimate tensile strength (9.650 vs 5.648 MPa [MP; P = .021] and 6.065 MPa [TA; P = .0403]). No significant differences in collagen and glycosaminoglycan content were found in the steroid-treated groups. Pyridinoline crosslinking was significantly decreased in explants exposed to TA compared with controls (P = .027). CONCLUSION: Exposure of MP to articular cartilage explants was chondrotoxic, and exposure of articular cartilage explants to MP or TA resulted in significant decreases in mechanical properties of articular cartilage explants compared with controls. Clinicians should be judicious regarding use of intra-articular steroids, particularly in patients with intact healthy articular cartilage.

The Statistical Fragility of Operative vs Nonoperative Management for Achilles Tendon Rupture: A Systematic Review of Comparative Studies.

BACKGROUND: The statistical significance of randomized controlled trials (RCTs) and comparative studies is often conveyed utilizing the P value. However, P values are an imperfect measure and may be vulnerable to a small number of outcome reversals to alter statistical significance. The interpretation of the statistical strength of these studies may be aided by the inclusion of a Fragility Index (FI) and Fragility Quotient (FQ). This study examines the statistical stability of studies comparing operative vs nonoperative management for Achilles tendon rupture. METHODS: A systematic search was performed of 10 orthopaedic journals between 2000 and 2021 for comparative studies focusing on management of Achilles tendon rupture reporting dichotomous outcome measures. FI for each outcome was determined by the number of event reversals necessary to alter significance (P < .05). FQ was calculated by dividing the FI by the respective sample size. Additional subgroup analyses were performed. RESULTS: Of 8020 studies screened, 1062 met initial search criteria with 17 comparative studies ultimately included for analysis, 10 of which were RCTs. A total of 40 outcomes were examined. Overall, the median FI was 2.5 (interquartile range [IQR] 2-4), the mean FI was 2.90 (±1.58), the median FQ was 0.032 (IQR 0.012-0.069), and the mean FQ was 0.049 (±0.062). The FI was less than the number of patients lost to follow-up for 78% of outcomes. CONCLUSION: Studies examining the efficacy of operative vs nonoperative management of Achilles tendon rupture may not be as statistically stable as previously thought. The average number of outcome reversals needed to alter the significance of a given study was 2.90. Future analyses may benefit from the inclusion of a fragility index and a fragility quotient in their statistical analyses.

Osteochondral Allografts in Knee Surgery: Narrative Review of Evidence to Date.

Knee articular cartilage defects can result in significant pain and loss of function in active patients. Osteochondral allograft (OCA) transplantation offers a single-stage solution to address large chondral and osteochondral defects by resurfacing focal cartilage defects with mature hyaline cartilage. To date, OCA transplantation of the knee has demonstrated excellent clinical outcomes and long-term survivorship. However, significant variability still exists among clinicians with regard to parameters for graft acceptance, surgical technique, and rehabilitation. Technologies to optimize graft viability during storage, improve osseous integration of the allograft, and shorten recovery timelines after surgery continue to evolve. The purpose of this review is to examine the latest evidence on treatment indications, graft storage and surgical technique, patient outcomes and survivorship, and rehabilitation after surgery.

Statistical Fragility of Single-Row Versus Double-Row Anchoring for Rotator Cuff Repair: A Systematic Review of Comparative Studies.

Background: Comparative studies and randomized controlled trials (RCTs) often use the P (probability) value to convey the statistical significance of their findings. P values are an imperfect measure, however, and are vulnerable to a small number of outcome reversals to alter statistical significance. The inclusion of a fragility index (FI) and fragility quotient (FQ) may aid in the interpretation of a study's statistical strength. Purpose/Hypothesis: The purpose of this study was to examine the statistical stability of studies comparing single-row to double-row rotator cuff repair. It was hypothesized that the findings of these studies would be vulnerable to a small number of outcome event reversals, often fewer than the number of patients lost to follow-up. Study Design: Systematic review; Level of evidence, 3. Methods: We analyzed comparative studies and RCTs on primary single-row versus double-row rotator cuff repair that were published between 2000 and 2021 in 10 leading orthopaedic journals. Statistical significance was defined as a P < .05. The FI for each outcome was determined by the number of event reversals necessary to alter significance. The FQ was calculated by dividing the FI by the respective sample size. Results: Of 4896 studies screened, 22 comparative studies, 10 of which were RCTs, were ultimately included for analysis. A total of 74 outcomes were examined. Overall, the median FI was 2 (interquartile range [IQR], 1-3), and the median FQ was 0.035 (IQR, 0.020-0.057). The mean FI was 2.55 ± 1.29, and the mean FQ was 0.043 ± 0.027. In 64% of outcomes, the FI was less than the number of patients lost to follow-up.) Additionally, 81% of significant outcomes needed just a single outcome reversal to lose their significance. Conclusion: Over half of the studies currently used to guide clinical practice have a number of patients lost to follow-up greater than their FI. The results of these studies should be interpreted within the context of these limitations. Future analyses may benefit from the inclusion of the FI and the FQ in their statistical analyses.

No Difference in Complications Between Elbow Ulnar Collateral Ligament Reconstruction With the Docking and Modified Jobe Techniques: A Systematic Review and Meta-analysis.

BACKGROUND: The most commonly used techniques for elbow ulnar collateral ligament reconstruction (UCLR) are the docking and modified Jobe figure-of-8 techniques. Previous literature has suggested that UCLR with the docking technique is associated with fewer complications; however, these studies included results from the original classic Jobe technique without controlling for the effects of flexor pronator mass (FPM) detachment and routine submuscular ulnar nerve transposition (UNT). PURPOSE/HYPOTHESIS: This study sought to compare the rates of complications and subsequent unplanned surgical procedures between the docking and figure-of-8 techniques. We hypothesized that there would be no significant difference in the rates of complications or subsequent unplanned surgical procedures between the techniques when the FPM was preserved and no routine submuscular UNT was performed. STUDY DESIGN: Systematic review and meta-analysis; Level of evidence, 4. METHODS: This study was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A series of mixed-effects multivariate metaregression models were implemented using the restricted maximum likelihood method. Complications and subsequent unplanned surgical procedures were modeled as Freeman-Tukey transformed incidence rates for variance stabilization, and nerve-specific complications were assessed as the Freeman-Tukey transformed proportion of cases, with back-transformation to estimate summary effects. RESULTS: There were 19 studies eligible for qualitative analysis, consisting of 1788 cases of UCLR (303 docking, 1485 figure-of-8), 18 of which were suitable for quantitative analysis (1769 cases; 291 docking, 1478 figure-of-8). A total of 338 complications were reported (17 for docking, 321 for figure-of-8), the majority of which were nerve related. Additionally, a total of 75 subsequent unplanned surgical procedures were related to the index UCLR procedure. There was no significant difference in the rate of complications (P = .146) or proportion of cases with nerve-specific complications (P = .127) between the docking and figure-of-8 techniques when controlling for FPM preservation versus detachment with submuscular UNT. FPM detachment with submuscular UNT was independently associated with a significantly higher proportion of postoperative nerve-related complications (P = .004). There was also no significant difference in the rates of subsequent unplanned surgical procedures between the docking and figure-of-8 techniques (P = .961), although FPM detachment with routine submuscular UNT was independently associated with a significantly higher incidence of subsequent unplanned surgical procedures. CONCLUSION: The results of this study demonstrate no significant difference in the rates of complications or subsequent unplanned surgical procedures between the figure-of-8 and docking techniques for UCLR when controlling for FPM preservation versus detachment with submuscular UNT. With modern muscle-sparing approaches and avoiding submuscular UNT, the modified Jobe technique does not differ significantly from the docking technique in terms of complication rates, proportions of cases with nerve-specific complications, or rates of subsequent unplanned surgical procedures.

Modified Jobe Versus Docking Technique for Elbow Ulnar Collateral Ligament Reconstruction: A Systematic Review and Meta-analysis of Clinical Outcomes.

BACKGROUND: The modified Jobe and docking techniques are the most common techniques used for elbow ulnar collateral ligament (UCL) reconstruction. Previous systematic reviews have suggested that the docking technique results in superior outcomes as compared with the Jobe (figure-of-8) technique. However, these included results from earlier studies in which the flexor-pronator mass (FPM) was detached and an obligatory submuscular ulnar nerve transposition was performed. PURPOSE/HYPOTHESIS: The purpose was to compare the outcomes and return-to-play (RTP) time between the docking and figure-of-8 techniques for UCL reconstruction. We hypothesized that there would be no significant difference in the proportion of excellent outcomes between techniques when the FPM was preserved and no obligatory submuscular ulnar nerve transposition was performed. We also hypothesized that there would be no significant difference in RTP time between techniques. STUDY DESIGN: Systematic review and meta-analysis. METHODS: This study was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. In the primary analysis, techniques were compared in random effects models by using the restricted maximum likelihood method, with weighted effect sizes calculated as the Freeman-Tukey double-arcsine transformed proportion of excellent outcomes for variance stabilization and with summary effects estimated from the inverse double-arcsine transformation per the harmonic mean of the sample sizes. Mean RTP times for techniques were compared in a separate model. RESULTS: There were 21 eligible articles identified, with results for 1842 UCL reconstructions (n = 320, docking; n = 1466, figure-of-8). Without controlling for the effects of flexor-pronator detachment and submuscular ulnar nerve transposition, a significantly larger proportion of excellent outcomes was observed with docking reconstruction (86.58%; 95% CI, 80.42%-91.85%) than with figure-of-8 reconstruction (76.76%; 95% CI, 69.65%-83.25%; P = .031); however, there was no significant difference between techniques when controlling for FPM preservation or detachment with submuscular nerve transposition (P = .139). There was no significant difference between techniques in time to return to sports (P = .729), although no reconstructions with FPM detachment and submuscular ulnar nerve transposition were available for RTP time analysis. CONCLUSION: There was no significant difference in the proportion of excellent Conway Scale outcomes or RTP time between the docking and modified Jobe techniques for UCL reconstruction when the FPM was preserved and routine submuscular ulnar nerve transposition was not performed.

The Statistical Fragility of Single-Bundle vs Double-Bundle Autografts for ACL Reconstruction: A Systematic Review of Comparative Studies.

BACKGROUND: The statistical significance of a given study outcome can be liable to small changes in findings. P values are common, but imperfect statistical methods to convey significance, and inclusion of the fragility index (FI) and fragility quotient (FQ) may provide a clearer perception of statistical strength. PURPOSE/HYPOTHESIS: The purpose was to examine the statistical stability of studies comparing primary single-bundle to double-bundle anterior cruciate ligament reconstruction (ACLR) utilizing autograft and independent tunnel drilling. It was hypothesized that the study findings would be vulnerable to a small number of outcome event reversals, often less than the number of patients lost to follow-up. STUDY DESIGN: Systematic review; Level of evidence, 2. METHODS: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the authors searched PubMed for comparative studies and randomized controlled trials (RCTs) published in select journals, based on impact factor, between 2005 and 2020. Risk-of-bias assessment and methodology scoring were conducted for the included studies. A total of 48 dichotomous outcome measures were examined for possible event reversals. The FI for each outcome was determined by the number of event reversals necessary to alter significance. The FQ was calculated by dividing the FI by the respective sample size. RESULTS: Of the 1794 studies screened, 15 comparative studies were included for analysis; 13 studies were RCTs. Overall, the mean FI and FQ were 3.14 (IQR, 2-4) and 0.050 (IQR, 0.032-0.062), respectively. For 72.9% of outcomes, the FI was less than the number of patients lost to follow-up. CONCLUSION: Studies comparing single-bundle versus double-bundle ACLR may not be as statistically stable as previously thought. Comparative studies and RCTs are at substantial risk for statistical fragility, with few event reversals required to alter significance. The reversal of fewer than 4 outcome events in a treatment group can alter the statistical significance of a given result; this is commonly less than the number of patients lost to follow-up. Future comparative study analyses might consider including FI and FQ with P values in their statistical analysis.

The Statistical Fragility of Hamstring Versus Patellar Tendon Autografts for Anterior Cruciate Ligament Reconstruction: A Systematic Review of Comparative Studies.

BACKGROUND: Evidence-based medicine utilizes data to inform clinical decision making, despite the ability of a small number of outcome reversals to change statistical significance. P values are common measurements of statistical significance that possess inherent flaws. The inclusion of the fragility index (FI) and fragility quotient (FQ) may provide a clearer conveyance of statistical strength. PURPOSE/HYPOTHESIS: The purpose was to examine the statistical stability of studies comparing hamstring tendon and bone-patellar tendon-bone autografts in primary single-bundle anterior cruciate ligament reconstruction with independent tunnel drilling. We hypothesized that the findings of these studies are vulnerable to a small number of outcome event reversals, often fewer than the number of patients lost to follow-up. STUDY DESIGN: Systematic review. METHODS: Comparative studies and randomized controlled trials (RCTs) published in 10 leading orthopaedic journals between 2000 and 2020 were analyzed. Statistical significance was defined as a P value ≤.05. FI for each outcome was determined by the number of event reversals necessary to alter significance. FQ was calculated by dividing the FI by the respective sample size. RESULTS: Of the 1803 studies screened, 643 met initial search criteria, with 18 comparative studies ultimately included for analysis, 8 of which were RCTs. A total of 114 outcomes were examined. Overall, the mean (interquartile range) FI and FQ were 3.77 (2-4) and 0.040 (0.016-0.055), respectively. The FI was less than the number of patients lost to follow-up for 76.3% of outcomes. CONCLUSION: Studies examining graft choice for anterior cruciate ligament reconstruction may not be as statistically stable as previously thought. Comparative studies and RCTs are at substantial risk for statistical fragility, with few event reversals required to alter significance. The reversal of <4 outcome events in a treatment group can alter the statistical significance of a given result; this is commonly fewer than the number of patients lost to follow-up. Future comparative study analyses might consider including FI and FQ with P values in their statistical analysis.