Decreased Instability in High-Risk (Hip-Spine 2B) Patients After Modifications of Surgical Planning and Technique.

BACKGROUND: Patients undergoing primary total hip arthroplasty (THA) who have spinal deformity and a stiff spine are the highest-risk group for instability. Despite the increasing use of dual-mobility cups and large femoral heads, dislocation remains a major complication after THA. Preoperative planning becomes a critical aspect of ensuring precise component positioning within a safe zone. The purpose of this study was to investigate dislocation rates over a 9-year period. METHODS: A retrospective review of 4,731 THAs performed by three orthopaedic surgeons between January 2014 and March 2023 was performed. Spino-pelvic measurements were conducted to determine the Hip-Spine Classification group for each patient. Only patients classified as 2B (Pelvic Incidence-Lumbar Lordosis > 10° and ΔSacral Slope < 10°) were eligible. Both absolute and relative dislocation frequencies were then analyzed using time-series analysis techniques and Fisher's exact tests. RESULTS: A total of 281 Hip-Spine 2B patients undergoing primary THA were eligible for analysis (57% women; mean age, range: 66 years, 23 to 87; mean BMI, range: 28, 16 to 45). The overall dislocation rate was 4.3%. Use of femoral head sizes ≥ 40 mm increased from 4% in 2014 to 2019 to 37% in 2020 to 2023 (P < 0.001), while the use of dual-mobility cups decreased from 100% in 2014 to 2019 to 37% in 2020 to 2023 (P < 0.001). Acetabular component planning was changed from the supine plane to the standing plane in February 2020. Those changes in surgical practice were notably correlated with a significant decrease in dislocation rates from 6.8% in 2014 to 2019 to 1.5% in 2020 to 2023 (P = 0.03). CONCLUSION: Our study demonstrates that the introduction of advanced preoperative THA planning to the standing plane, coupled with precise intra-operative technology for implant placement, can significantly reduce the risk of instability in high-risk THA patients. Notably, we observed a significant decrease in dislocation rates, which aligned with the shift in surgical practice.

Is Tibial Bone Mineral Density Related to Sex, Age, Preoperative Alignment, or Fixation Method in Primary Total Knee Arthroplasty?

BACKGROUND: Cementless total knee arthroplasty (TKA) has regained interest for its potential for long-term biologic fixation. The density of the bone is related to its ability to resist static and cyclic loading and can affect long-term implant fixation; however, little is known about the density distribution of periarticular bone in TKA patients. Thus, we sought to characterize the bone mineral density (BMD) of the proximal tibia in TKA patients. METHODS: We included 42 women and 50 men (mean age 63 years, range: 50 to 87; mean body mass index 31.6, range: 20.5 to 49.1) who underwent robotic-assisted TKA and had preoperative computed tomography scans with a BMD calibration phantom. Using the robotic surgical plan, we computed the BMD distribution at 1 mm-spaced cross-sections parallel to the tibial cut from 2 mm above the cut to 10 mm below. The BMD was analyzed with respect to patient sex, age, preoperative alignment, and type of fixation. RESULTS: The BMD decreased from proximal to distal. The greatest changes occurred within ± 2 mm of the tibial cut. Age did not affect BMD for men; however, women between 60 and 70 years had higher BMD than women ≥ 70 years for the total cut (P = .03) and the medial half of the cut (P = .03). Cemented implants were used in 1 86-year-old man and 18 women (seven < 60 years, seven 60 to 70 years, and four ≥ 70 year old). We found only BMD differences between cemented or cementless fixation for women < 60 years. CONCLUSIONS: To our knowledge, this is the first study to characterize the preoperative BMD distribution in TKA patients relative to the intraoperative tibial cut. Our results indicate that while sex and age may be useful surrogates of BMD, the clinically relevant thresholds for cementless knees remain unclear, offering an area for future studies.

No Difference in Limb Alignment Between Kinematic and Mechanical Alignment Robotic-Assisted Total Knee Arthroplasty.

BACKGROUND: Individualized alignment techniques have gained major interest in an effort to increase satisfaction among total knee arthroplasty patients. This study aimed to compare postoperative alignment between kinematic alignment (KA) and mechanical alignment (MA) and assess whether KA significantly deviates from the principle of aligning the limb as close to neutral alignment as possible. METHODS: There were 234 patients who underwent robotic-assisted total knee arthroplasty using an unrestricted KA and a strict MA technique (KA: 145, MA: 89). The lateral distal femoral angle, medial proximal tibia angle, and the resultant arithmetic hip-knee-ankle angle (aHKA) were measured. The aHKA < 0 indicated varus alignment, while the aHKA > 0 indicated valgus knee alignment. The primary outcome was the frequency of cases that resulted in an aHKA of ± 4° of neutral (0°), as assessed on full-leg standing radiographs obtained at 6 weeks postoperatively. The secondary outcome was the change in coronal plane alignment of the knee classification type from preoperative to postoperative between the MA and KA groups. RESULTS: The mean preoperative aHKA was similar between the 2 groups (P = .19). The KA group had a mean postoperative aHKA of -1.4 ± 2.4°, while the MA group had a mean postoperative aHKA of -0.5 ± 2.1°. No significant difference in limb alignment was identified between KA and MA cases that resulted in hip-knee-ankle angle of ± 4° being neutral (91.7 versus 96.6%, P = .14). There were 97.2% of cases in the KA group that fell within the ± 5° range. The MA group was associated with a significantly higher rate of coronal plane alignment of the knee classification type change from preoperatively to postoperatively (P < .001). CONCLUSIONS: Kinematic alignment achieved similar postoperative aHKA compared to MA, and thus did not significantly deviate from the principle of aligning the limb as close to neutral alignment as possible. Surgeons should feel comfortable starting to introduce individualized alignment techniques. Without being restricted by boundaries, postoperative alignment will be within 5 degrees of neutral 97% of the time.

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.

Definitions and consequences of current alignment techniques and phenotypes in total knee arthroplasty (TKA) - there is no winner yet.

Dissatisfaction following total knee arthroplasty (TKA) has been extensively documented and it was attributed to numerous factors. In recent years, significant focus has been directed towards implant alignment and stability as potential causes and solutions to this issue. Surgeons are now exploring a more personalized approach to TKA, recognizing the importance of thoroughly understanding each individual patient's anatomy and functional morphology. A more comprehensive preoperative analysis of alignment and knee morphology is essential to address the unresolved questions in knee arthroplasty effectively. The crucial task of determining the most appropriate alignment strategy for each patient arises, given the substantial variability in bone resection resulting from the interplay of phenotype and the alignment strategy chosen. This review aims to comprehensively present the definitions of different alignment techniques in all planes and discuss the consequences dependent on knee phenotypes.Level of evidence V.

Early Complication Rates Are Equivalent Between Isolated Cartilage Restoration and Concomitant Cartilage Restoration and Osteotomy of the Knee.

OBJECTIVE: Realignment osteotomy performed concomitantly with cartilage restoration typically requires early restricted weightbearing and can add significant morbidity, potentially leading to an increased risk of early perioperative complications. The purpose of this study was to compare the 30-day complication rates after isolated cartilage restoration (ICR) versus concomitant cartilage restoration and osteotomy (CRO) using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. DESIGN: NSQIP registries between 2006 and 2019 were queried using Current Procedural Terminology codes to identify patients undergoing ICR (autologous chondrocyte implantation, osteochondral autograft transfer, or osteochondral allograft transplantation) and CRO (with concomitant high tibial osteotomy, distal femoral osteotomy, and/or tibial tubercle osteotomy). Complications rates between treatment groups were compared using multivariate logistic regression analyses adjusted for sex, age, steroid use, and respiratory status. RESULTS: A total of 773 ICR and 97 CRO surgical procedures were identified. Mean patient ages were 35.9 years for the ICR group and 31.2 years for the CRO group. Operative time was significantly longer in the CRO group (170.8 min) compared with the ICR group (97.8 min). Multivariate analysis demonstrated no significant differences in rates of PE, VTE, and all-cause readmission between the ICR and CRO groups. No events of wound disruption, SSI and reoperation were found in the CRO group, while the ICR group was characterized by low rates of wound disruption, reoperation, and SSI (<1.1%). CONCLUSIONS: These findings further support concomitant osteotomy with cartilage restoration when appropriate and aid surgeons in the preoperative counseling of patients undergoing cartilage restoration treatment.

Low early complication rates after arthroscopic meniscus repair and meniscectomy.

PURPOSE: To evaluate the 30-day complication rates after arthroscopic meniscus repair and meniscectomy using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database, with subgroup analysis of patients aged > 40 years. METHODS: NSQIP registries between 2006 and 2019 were queried using Current Procedural Terminology codes to identify patients undergoing arthroscopic meniscus repair (CPT 29882, 29883) and meniscectomy (29880, 29881). The following 30-day complications were assessed: pulmonary embolism (PE), venous thromboembolism (VTE), surgical site infection (SSI), reoperation, and readmission. Complications rates between treatment groups were compared using multivariate logistic regression analyses adjusted for sex, age, steroid use, and smoking/dyspnoea/COPD. A subgroup analysis was performed for patients aged > 40 years. RESULTS: A total 6354 meniscus repairs and 99,372 meniscectomies were identified. Complication rates were < 1% for both meniscus repair and meniscectomy. Meniscus repair was associated with significantly higher rates of PE, VTE, and readmission compared to meniscectomy: PE (0.2% vs 0.1%, p < 0.001), VTE (0.8% vs 0.4%, p < 0.001), superficial SSI (0.1% vs 0.2%, n.s), deep SSI (0.07% vs 0.1%, n.s), reoperation (0.5% vs 0.4%, n.s), and readmission (0.9% vs 0.8%, p = 0.003). Among patients aged > 40 years, complication rates were < 1.3% for both meniscus repair and meniscectomy. Similar trends and rates were found in patients aged > 40 years undergoing meniscus repair versus meniscectomy: PE (0.38% vs 0.12%, p < 0.001), VTE (1.07% vs 0.46%, p < 0.001), superficial SSI (0.03% vs 0.19%, n.s), deep SSI (0.1% vs 0.06%, n.s), reoperation (0.48% vs 0.43%, n.s), and readmission (1.2% vs 0.85%, p = 0.01). CONCLUSION: Arthroscopic meniscus repair and meniscectomy are both low-risk procedures with 30-day complication rates < 1% overall and < 1.3% among patients aged > 40 years. These findings support meniscus repair whenever feasible in the setting of preserved articular cartilage. Understanding of the short-term complication rates after arthroscopic meniscus repair and meniscectomy can aid surgeons in providing comprehensive preoperative counselling to patients considering such treatments, specifically when discussing the risks and benefits of meniscus repair. LEVEL OF EVIDENCE: III.

Geographic Variation in Knee Phenotypes Based on the Coronal Plane Alignment of the Knee Classification: A Systematic Review.

BACKGROUND: The extent of geographic variation in knee phenotypes remains unclear. The Coronal Plane Alignment of the Knee (CPAK) Classification proposes 9 coronal plane phenotypes based on constitutional limb alignment and joint line obliquity. This systematic review aims to examine differences in the distributions of CPAK types across geographic regions. METHODS: A systematic review of the literature was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies reporting distributions of knee phenotypes according to the CPAK classification for healthy and/or arthritic knees were included. RESULTS: There were 7 studies included, accounting for 5,964 knees in 3,917 subjects. Among healthy knees (n = 1,214), CPAK type II was the most common type in Belgium (39.2%), Taiwan (39.3%), and India (25.6%). Among arthritic knees (n = 2,804), CPAK type I was the most common in France (33.4%), India (58.8%), and Japan (53.8%), whereas CPAK type II was the most common in Australia (32.8%). The proportion of CPAK type I and II knees varied significantly across geographic regions among healthy (P < .01) and arthritic knees (P < .01). CONCLUSION: Significant variation in CPAK distributions exists between countries. Further work is needed to delineate racial and sexual differences in CPAK types, which were not explored in this article. A better understanding of population-level variability in knee phenotypes may enable orthopaedic surgeons to offer a more personalized approach to knee arthroplasty.

Current Concepts in Alignment in Total Knee Arthroplasty.

BACKGROUND: In an effort to increase satisfaction among total knee arthroplasty (TKA) patients, emphasis has been placed on implant positioning and limb alignment. Traditionally, the aim for TKA has been to achieve a neutral mechanical alignment (MA) to maximize implant longevity. However, with the recent spike in interest in individualized alignment techniques and with the advent of new technologies, surgeons are slowly evolving away from classical MA. METHODS: This review elucidates the differences in alignment techniques for TKA, describes the concept of knee phenotypes, summarizes comparative studies between MA and individualized alignment, and provides a simple way to incorporate the latter into surgeons' practice. RESULTS: In order to manage patients by applying these strategies in day-to-day practice, a basic understanding of the aforementioned concepts is essential. Transition to an individualized alignment technique should be done gradually with caution in a stepwise approach. CONCLUSION: Alignment and implant positioning are now at the heart of the debate and surgeons are investigating a more personalized approach to TKA.

Outcomes of Arthroscopic Lysis of Adhesions for the Treatment of Postoperative Knee Arthrofibrosis: A Systematic Review.

Background: Postoperative knee arthrofibrosis is a common and potentially detrimental complication affecting knee function and gait. Several cohort studies have reported good outcomes after arthroscopic lysis of adhesions (LOA) with manipulation under anesthesia (MUA). Purpose: To review the literature assessing the efficacy and complications of arthroscopic LOA and MUA for postoperative arthrofibrosis of the knee and evaluate whether any relevant subgroups are associated with different clinical presentation and outcomes. Study Design: Systematic review; Level of evidence, 4. Methods: This review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Eligible studies published from January 1, 1990, to April 1, 2021, were identified through a search of the US National Library of Medicine (PubMed/MEDLINE), EMBASE, and Cochrane databases. All studies included in this analysis included pre- and postoperative range of motion measurements for their treated patients. Studies reporting outcomes for patients with isolated cyclops lesions after anterior cruciate ligament reconstruction were excluded. Results: Eight studies comprising 240 patients were included. The mean time from index surgery to arthroscopic LOA and MUA was 8.4 months, and the mean postoperative follow-up was at 31.2 months. All studies demonstrated a significant improvement (41.6°) in arc of motion after arthroscopic LOA. Clinically significant improvements in outcome measures, including the International Knee Documentation Committee, Western Ontario and McMaster Universities Osteoarthritis Index, and Knee injury and Osteoarthritis Outcome Score, were reported after arthroscopic LOA across all applicable studies. Of 240 patients, a single complication (synovial fistula) occurred after LOA and MUA, which resolved without intervention. Conclusion: The results of this review indicated that arthroscopic LOA and MUA is a safe and efficacious treatment for postoperative arthrofibrosis of the knee.

Cryoneurolysis Is a Safe, Effective Modality to Improve Rehabilitation after Total Knee Arthroplasty.

Although long term pain and mobility outcomes in total knee arthroplasties (TKA) are successful, many patients experience significant amount of debilitating pain during the immediate post-operative period that necessitates narcotic use. Percutaneous cryoneurolysis to the infrapatellar saphenous and anterior femoral cutaneous nerves may help to better restore function and rehabilitation after surgery while limiting narcotic consumption. A retrospective chart review of primary TKA patients receiving pre-operative cryoneurolysis from 2019 to 2020 was performed to assess total opioid morphine milligram equivalents (MME) consumed inpatient and at interval follow-up. Demographics and medical comorbidities were compared between cryoneurolysis and age-matched control patients to assess baseline characteristics. Functional rehabilitation outcomes, including knee range of motion (ROM), ambulation distance, and Boston AM-PAC scores, as well as patient reported outcomes using the KOOS JR and SF-12 scores were analyzed using STATA 17 Software. The analysis included 29 cryoneurolysis and 28 age-matched control TKA patients. Baseline demographics and operative technique were not significant between groups. Although not statistically significant, cryoneurolysis patients had a shorter length of stay (2.5 vs. 3.5 days) and overall less inpatient and outpatient MME requirements. Cryoneurolysis patients had statistically significant improved 6-week ROM and 1-year follow-up KOOS JR and SF-12 mental scores compared to the control. There were no differences in complication rates. Cryoneurolysis is a safe, effective treatment modality to improve active functional recovery and patient satisfaction after TKA by reducing MME requirements. Patients who underwent cryoneurolysis had on average fewer MME prescribed during the perioperative period, improved active ROM, and improved patient-reported outcomes with no associated increased risk of infections, deep vein thrombosis, or neurologic complications.

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.

Salvage Fixation With a Single Nitinol Compression Staple for a Lateralized Fibular Tunnel in Posterolateral Corner Reconstruction of the Knee.

Recognition and treatment of injuries to the posterolateral (PLC) corner of the knee have increased in recent decades. Despite advancements in surgical technique, complications can occur in up to 20% of PLC reconstructions. Lateralization of the fibular tunnel during drilling is a common intraoperative pitfall and can lead to cortical breach or fibular head fracture after graft tensioning. Compression staples have been increasingly used for fracture fixation in the hand, foot, and ankle. Because of its pseudo-elastic properties, insertion of a low-profile, compressive Nitinol staple could serve as an intraoperative salvage technique to reinforce and prevent failure through a thin lateral cortex of the fibular head. The purpose of this Technical Note is to describe a reproducible technique for the implementation of a Nitinol staple for reinforcement of a lateralized fibular tunnel in posterolateral corner reconstruction.

Prophylaxis for Venous Thromboembolic Events in Elective Total Hip and Total Knee Arthroplasty.

Venous thromboembolism (VTE) is a serious complication after major orthopaedic operations, such as a total hip (THA) and knee (TKA) arthroplasty. Therefore, perioperative VTE prophylaxis is recommended; a multitude of modern options are available, including both pharmacologic (aspirin, unfractionated and lowmolecular- weight heparin, vitamin K antagonists, and novel oral anticoagulants) and/or mechanical interventions (early mobilization, graduated compression stockings, intermittent pneumatic compression devices, and venous foot pumps). However, because of the abundance of these possibilities, it is crucial to understand the benefits and drawbacks of each VTE prophylaxis option to ensure that the optimal treatment plan is developed for each patient. The American College of Chest Physicians (AACP) and the American Academy of Orthopaedic Surgeons (AAOS) have both published individual guidelines on VTE prophylaxis regimens, alongside numerous studies evaluating the efficacy and outcomes of the different prophylaxis modalities. The purpose of this review is to provide a summary of the evidence on VTE prophylaxis after elective total hip and knee arthroplasty based on current guidelines and highlight the major concerns and potential complications.

Anatomic study of an anterior portal for percutaneous internal fixation of capitellum fractures.

BACKGROUND: Fractures of the capitellum are uncommon and difficult to treat surgically. Capitellar open reduction-internal fixation uses a lateral open approach with posterior-to-anterior or anterior-to-posterior screw fixation. We investigated the use of an anterior portal for placement of anterior-to-posterior screw fixation through cadaveric measurement of the anatomic relationships from an anteriorly to posteriorly placed Kirschner wire (K-wire) to anterior elbow structures and calculated the percentage of articular surface accessed from the anterior portal. METHODS: Eight fresh-frozen cadaveric elbows without radiographic or cutaneous evidence of prior trauma or surgery were used for this study. An arthroscopic proximal anteromedial portal was cannulized, and the radiocapitellar joint was evaluated. A single 1-cm portal was placed 1 cm distal to the elbow flexion crease and based lateral to the biceps tendon. The location of the portal was confirmed with a spinal needle, and blunt dissection with a hemostat was performed down to capsular tissue and for arthrotomy. A spinal needle sheath was threaded over a blunt switching stick and served as a cannula for placement of a 0.062 K-wire. Articular mapping was performed with cartilage scraping by the K-wire; the K-wire was then placed at the perceived center along the proximal-to-distal and radial-to-ulnar axis of the capitellum. Fluoroscopic confirmation of the wire's location was performed. Under loupe magnification, anatomic dissection was performed and the shortest distance measurements were recorded with digital calipers from the K-wire to the dissected structures. Capitellar articular measurements were recorded, in addition to the articular area defined by the K-wire. Data analysis was performed, and the average distance and standard deviation (in millimeters) were calculated. For structures that were pierced by or touching the K-wire, the distance was recorded as 0.1 mm. RESULTS: The average distance from the K-wire to the radial, lateral antebrachial cutaneous, and median nerves was 1.8 mm, 11.5 mm, and 28.0 mm, respectively. The average distance from the median cubital vein and biceps tendon was 3.7 mm and 13.4 mm, respectively. The pin track pierced the brachioradialis and supinator muscles in all but 1 specimen. The average capitellar articular surface marked was 39.1% of the calculated articular footprint of the capitellum. CONCLUSIONS: The anterior portal to the capitellum is directly adjacent to the radial nerve and lateral antebrachial cutaneous nerve, where each is susceptible to injury. We recommend blunt dissection and insertion of a cannula to allow drilling and placement of internal fixation in a relatively safe manner with respect to neurovascular structures.

Use of elevated liners in primary total hip arthroplasty: a systematic review of the literature.

PURPOSE: Instability remains one of the most frequent complications requiring revision surgery after primary total hip arthroplasty (THA). Elevated liners are often utilized to reduce the risk of dislocation; however, the literature is inconclusive, with no systematic reviews summarizing the data. Thus, this systematic review aimed to establish a consensus for the efficacy of elevated liners in primary THA by determining rates of overall revision and revision specifically for recurrent dislocation. MATERIALS AND METHODS: This study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eligible randomized-controlled trials and observational studies reporting on the use of elevated liners in primary total hip arthroplasty were identified through May 2020. A random effects model meta-analysis was conducted, and the I2 statistic was used to assess for heterogeneity. RESULTS: Eight studies met inclusion criteria, and overall, 26,507 patients undergoing primary THA with use of an elevated liner were included. In aggregate, the most common cause of revision was recurrent hip dislocation (1.3%, N = 82/6,267) followed by joint infection (1.2%, N = 45/3,772) and acetabular loosening (0.3%, N = 10/3,772). Notably, elevated liners were associated with a lower risk of revision for recurrent dislocation compared to neutral liners (HR: 0.74; 95% CI: 0.55-1.00; p = 0.048). CONCLUSION: This review found that after primary THA with the use of elevated liners, hip dislocation and prosthetic joint infection continued to be the most frequent reasons for revision surgery. However, elevated liners had a lower risk of revision for recurrent dislocation compared to neutral liners.

Highly cross-linked polyethylene in primary total knee arthroplasty is associated with a lower rate of revision for aseptic loosening: a meta-analysis of 962,467 cases.

BACKGROUND: The evolution in total knee arthroplasty (TKA) includes the highly cross-linked polyethylene (HXLPE) which has been reported as an effective manner to reduce the wear of the polyethylene and the osteolysis. The purpose of the present study is to synthesize the results of comparative studies between HXLPE and conventional polyethylenes and determine their effect in primary TKA. METHODS: The US National Library of Medicine (PubMed/MEDLINE) and the Cochrane Database of Systematic Reviews were queried for publications utilizing the following keywords: "cross-linked", "polyethylene", "HXLPE", "conventional", "total knee arthroplasty", "TKA", "total knee replacement" and "TKR" combined with Boolean operators AND and OR. RESULTS: Ten studies met the inclusion criteria and were included in the present meta-analysis with 962,467 patients. No significant difference was found regarding the revision rate for any reason between the patients who received HXLPE and those with conventional liner (OR 0.67; 95% CI 0.39-1.18; I2: 97.7%). In addition, there was no difference regarding the radiolucent lines between the two types of liners (OR 0.54; 95% CI 0.20-1.49; I2: 69.4%). However, with data coming from seven studies enrolling a total of 411,543 patients, it was demonstrated that patients who received HXLPE were less likely to be revised due to aseptic loosening compared to the patients with conventional liners (OR 0.35; 95% CI 0.31-0.39; I2: 0.0%). CONCLUSION: The present meta-analysis showed that regarding the overall revision rate and radiographic outcomes there was no significant difference between the two types of liners. On the other hand, the significantly less revision rate due to loosening supports the routine continued use of HXLPE in primary TKA.

Relatively Low Rate of Heterotopic Ossification Following Primary Total Knee Arthroplasty: A Systematic Review and Meta-analysis.

BACKGROUND: Heterotopic ossification (HO) is abnormal growth of ectopic bone and negatively affects the outcomes after total knee arthroplasty (TKA). This systematic review and meta-analysis were performed to characterize the prevalence and severity of HO after primary TKA. METHODS: A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Patient demographics, publication year, and HO prevalence after a primary TKA were recorded. A meta-analysis was performed to determine the overall prevalence of HO formation, and a subanalysis compared the studies published in different timeframes to determine whether a temporal effect exists for HO prevalence. RESULTS: Two thousand nine hundred eighty-eight patients underwent primary TKA across the included studies. Fourteen percent of patients (9% to 20%; I2: 93.68%) developed HO postoperatively during a mean follow-up of 40.1 months (11 to 108 months). HO rates seemed to decrease in studies published in more recent years, with a pooled HO prevalence of 5% (0% to 13%; I2: 92.26%) among studies published in the past 15 years compared with 18% (12% to 25%; I2: 92.49%) among studies published before then. CONCLUSION: Although studies reported a relatively low overall rate of HO after a primary TKA, the absence of a single, standardized classification system precludes the comparisons of HO severity between studies. Overall, HO prevalence seems to have decreased over time, likely reflecting the changes in perioperative medication protocols.

Total knee arthroplasty in dialysis patients: Is it safe? A systematic review of the literature.

PURPOSE: This systematic review characterizes the safety and efficacy of total knee arthroplasty (TKA) in end stage renal disease (ESRD) patients due to the unique challenges they face. RESULTS: The cumulative complication rate for 3684 patients on dialysis for ESRD after primary TKA was 25%(N = 925/3702), with incidence rates of 2.5%(N = 92/3702) for periprosthetic joint infection, 3.7%(N = 71/1895) for reoperations, and 2.5%(N = 90/3578) for mortality. CONCLUSION: Patients on dialysis for ESRD face significant mortality rates after primary TKA, in addition to other major complications. Careful counseling regarding risks and benefits should be provided prior to TKA in this population.