Stifle arthrodesis in dogs using semi-circular saw: Cadaveric study

The aim of this study was to develop a novel surgical technique for stifle arthrodesis in dogs using a semicircular saw for tibial and femoral ostectomies through a medial approach. Ten pelvic limbs from five canine cadavers underwent stifle arthrodesis. Prior to the surgical procedure, the limbs were radiographed to rule out musculoskeletal abnormalities. Additionally, the radiographs were used for surgical planning. For the tibial ostectomy, the center of the intercondylar eminences, the cranial limit of the tibial plateau, and the caudal cortex of the tibia were used as landmarks. In the femur, the groove of the insertion of the long digital extensor tendon and the caudal portion of the femoral cortex served as references. The most significant iatrogenic injury during the surgical procedures was the complete rupture of the long digital extensor tendon during the tibial cut in one of the stifles. Dome ostectomies facilitated interfragmentary contact, allowing for adjustment of the angulation between the fragments without the need for additional ostectomies or osteotomies. The medial approach provided a clear view of intra-articular structures without causing extensive damage to surrounding tissues. After the procedures, the limbs were radiographed to calculate angular measurements, and the final angulation (mean) of the knee joints was 134.7 ± 11°.

Does adding sacroiliac (type IV) resection to periacetabular (type II) resection increase complications or provide worse clinical outcomes? An institutional experience and systematic review

BACKGROUND AND OBJECTIVES

Internal hemipelvectomy is a limb sparing procedure most commonly indicated for malignant bone and soft tissue tumors of the pelvis. Partial resection and pelvic reconstruction may be challenging for orthopedic oncologists due to late presentation, high tumor burden, and complex anatomy. Specifically, wide resection of tumors involving the periacetabular and sacroiliac (SI) regions may compromise adjacent vital neurovascular structures, impair wound healing, or limit functional recovery. We aimed to present a series of patients treated at our institution who underwent periacetabular internal hemipelvectomy (Type II) with or without sacral extension (Type IV) in combination with a systematic review to investigate postoperative complications, functional outcomes, and implant and patient survival following pelvic tumor resection via Type II hemipelvectomy with or without Type IV resection.

MATERIALS AND METHODS

A surgical registry of consecutive patients treated with internal hemipelvectomy for primary or secondary pelvic bone tumors at our institution since 1994 was retrospectively reviewed. All type II resection patients were stratified into two separate cohorts, based on whether or not periacetabular resection was extended beyond the SI joint to include the sacrum (Type IV), as per the Enneking and Dunham classification. Patient demographics, operative parameters, complications, and oncological outcomes were collected. Categorical and continuous variables were compared with Pearson's chi square or Fisher's exact test and the Mann-Whitney U test, respectively. Literature review according to PRISMA guidelines queried studies pertaining to patient outcomes following periacetabular internal hemipelvectomy. The search strategy included combinations of the key words "internal hemipelvectomy", "pelvic reconstruction", "pelvic tumor", and "limb salvage". Pooled data was compared using Pearson's chi square. Statistical significance was established as p < 0.05.

RESULTS

A total of 76 patients were treated at our institution with internal hemipelvectomy for pelvic tumor resection, of whom 21 had periacetabular resection. Fifteen patients underwent Type II resection without Type IV involvement, whereas six patients had combined Type II/IV resection. There were no significant differences between groups in operative time, blood loss, complications, local recurrence, postoperative metastasis, or disease mortality. Systematic review yielded 69 studies comprising 929 patients who underwent internal hemipelvectomy with acetabular resection. Of these, 906 (97.5 %) had only Type II resection while 23 (2.5 %) had concomitant Type II/IV resection. While overall complication rates were comparable, Type II resection alone produced significantly fewer neurological complications when compared to Type II resection with sacral extension (3.9 % vs. 17.4 %, p = 0.001). No significant differences were found between rates of wound complications, infections, or construct failures. Local recurrence, postoperative metastasis, and survival outcomes were similar. Type II internal hemipelvectomy without Type IV resection on average produced higher postoperative MSTS functional scores than with Type IV resection.

CONCLUSION

In our series, the two groups exhibited no differences. From the systematic review, operative parameters, local recurrence or systemic metastasis, implant survival, and disease mortality were comparable in patients undergoing Type II internal hemipelvectomy alone compared to patients undergoing some combination of Type II/IV resection. However, compound resections increased the risk of neurological complications and experienced poorer MSTS functional scores.

Capsular and fascial closure with barbed sutures reduces blood loss compared to traditional interrupted sutures in total hip arthroplasty

BACKGROUND

STRATAFIX, a recently introduced barbed suture device, incorporates self-anchoring, knotless sutures with higher tensile strength and enhanced tissue-holding capacity compared to traditional braided absorbable sutures. This study aimed to compare the efficacy of barbed sutures and interrupted sutures in capsular and fascial closure during total hip arthroplasty.

METHODS

We retrospectively reviewed the records of patients who underwent total hip arthroplasty between April 2017 and March 2021. Overall, 547 patients were evaluated, comprising 77 men and 470 women (mean age: 64.5 years). Among them, 330 patients were in the interrupted suture (control) group, while 217 were in the barbed suture (BS) group. Data on surgical time, perioperative hemoglobin, length of hospital stay, complications such as transfusions and delayed wound healing, and dislocation rates were collected during the latest outpatient follow-up and compared between the two groups.

RESULTS

No differences were observed in intraoperative blood loss between the groups. However, the BS group exhibited significantly longer operative time, as well as significantly lower postoperative blood loss, total blood loss, and postoperative hemoglobin drop compared to the control group. Dislocation was reported in two cases within the control group, whereas no instances were recorded in the BS group.

CONCLUSION

The use of barbed sutures demonstrated effectiveness in reducing perioperative blood loss for capsular and fascial closure during total hip arthroplasty.

Predictive Modeling of Medical and Orthopaedic-Related 90-Day-Readmissions Following Primary Total Knee Arthroplasty

BACKGROUND

As the demand for total knee arthroplasty (TKA) escalates, 90-day readmissions have emerged as a pressing clinical and economic concern for the current value-based healthcare system. Consequently, healthcare providers have focused on estimating the risk levels of readmitted patients; however, it is unknown if specific factors are associated with different types of complications (i.e., medical or orthopaedic-related) that lead to readmissions. Therefore, this study aimed to: (1) Determine the overall, medical-related, and orthopaedic-related 90-day readmission rate; and (2) Develop a predictive model for risk factors affecting overall, medical-related, and orthopaedic-related 90-day readmissions following TKA.

METHODS

A prospective cohort of primary unilateral TKAs performed at a large tertiary academic center in the United States from 2016 to 2020 was included (n = 10,521 patients). Unplanned readmissions were reviewed individually to determine their primary cause, either medical or orthopaedic-related. Orthopaedic-related readmissions were specific complications affecting the joint, prosthesis, or surgical wound. Medical readmissions were due to any other cause requiring medical management. Multivariable logistic regression models were used to investigate associations between pre-specified risk factors and 90-day readmissions, as well as medical/orthopaedic-related readmissions independently.

RESULTS

Overall, the rate of 90-day readmissions was 6.7% (n = 704). Over 82% of these readmissions were due to medical-related causes (n = 580), with the remaining 18% being orthopaedic-related (n = 124) readmissions. The AUC for the 90-day readmission model was 0.68 (95% CI [confidence interval]: 0.67 to 0.70). Sex, smoking, length of stay (LOS), and discharge disposition (DD) were associated with orthopaedic readmission, while age, sex, race, Charlson Comorbidity Index (CCI), insurance, surgery day, opioid overdose risk (NARX) score, LOS, and DD were associated with medical-related 90-day readmissions.

CONCLUSION

Medical-related readmissions after TKA are more prevalent than orthopaedic-related readmissions. Through successfully constructing and validating multiple 90-day readmission predictive models, we highlight the distinct risk profiles for medical and orthopaedic-related readmissions. This emphasizes the necessity for nuanced, patient-specific risk stratification and preventive measures.

Soft tissue laxity is highly variable in patients undergoing total knee arthroplasty

BACKGROUND

One major goal of total knee arthroplasty (TKA) is to achieve balanced medial and lateral gaps in flexion and extension. While bone resections are planned by the surgeon, soft tissue laxity is largely intrinsic and patient-specific in the absence of additional soft tissue releases. We sought to determine the variability in soft tissue laxity in patients undergoing TKA.

METHODS

We retrospectively reviewed 113 patients undergoing TKA. Data on preoperative knee deformity were collected. Data from a dynamic intraoperative stress examination were collected by a robotic tracking system to quantify maximal medial and lateral opening in flexion (85-95 degrees) and extension (-5-20 degrees). T-tests were used to assess the differences between continuous variables.

RESULTS

A valgus stress opened the medial compartment a mean of 4.3 ± 2.3 mm (0.0-12.4 mm) in extension and 4.6 ± 2.3 mm (0.0-12.9 mm) in flexion. A varus stress opened the lateral compartment a mean of 5.4 ± 2.4 mm (0.3-12.6 mm) in extension and 6.2 ± 2.5 mm (0.0-13.4 mm) in flexion. The medial compartment of varus knees opened significantly more in response to valgus stress than valgus knees in both extension (5.2 mm vs. 2.6 mm; P < 0.0001) and flexion (5.4 mm vs 3.3 mm; P < 0.0001). The lateral compartment of valgus knees opened significantly more in response to varus stress than varus knees in both extension (6.7 mm vs. 4.8 mm; P < 0.0001) and flexion (7.4 mm vs. 5.8 mm; P = 0.0003).

CONCLUSIONS

Soft tissue laxity is highly variable in patients undergoing TKA, contributing anywhere from 0-13 mm to the post-resection gap. Only a small part of this variability is predictable by preoperative deformity. These findings have implications for either measured-resection or gap-balancing techniques.

LEVEL OF EVIDENCE

Level III.

Risk factors associated with re-revision following revision total knee arthroplasty: a systematic review

Aims

The aim of this study was to perform a systematic review and bias evaluation of the current literature to create an overview of risk factors for re-revision following revision total knee arthroplasty (rTKA).

Methods

A systematic search of MEDLINE and Embase was completed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. The studies were required to include a population of index rTKAs. Primary or secondary outcomes had to be re-revision. The association between preoperative factors and the effect on the risk for re-revision was also required to be reported by the studies.

Results

The search yielded 4,847 studies, of which 15 were included. A majority of the studies were retrospective cohorts or registry studies. In total, 26 significant risk factors for re-revision were identified. Of these, the following risk factors were consistent across multiple studies: age at the time of index revision, male sex, index revision being partial revision, and index revision due to infection. Modifiable risk factors were opioid use, BMI > 40 kg/m2, and anaemia. History of one-stage revision due to infection was associated with the highest risk of re-revision.

Conclusion

Overall, 26 risk factors have been associated with an increased risk of re-revision following rTKA. However, various levels of methodological bias were found in the studies. Future studies should ensure valid comparisons by including patients with identical indications and using clear definitions for accurate assessments.

Real-world accuracy of robotic-assisted total knee arthroplasty and its impact on expedited recovery

Despite total knee arthroplasty (TKA) being the gold standard for end-stage knee osteoarthritis, 20% of patients remain dissatisfied. Robotic-assisted arthroplasty promises unparalleled control of the accuracy of bone cuts, implant positioning, control of gap balance, and resultant hip-knee-ankle (HKA) axis. Patients underwent clinical and radiological assessments, including knee CT scans and patient-reported outcome measures (PROMs), preoperatively. Follow-up assessments were conducted at 2 weeks, 6 weeks, and 3 months post-operatively, with imaging repeated at 6 weeks. A total of 155 patients underwent robotic-assisted TKA and have completed 3 months of follow-up. Mean pre-operative HKA axis was 7.39 ± 5.52 degrees varus, improving to 1.34 ± 2.22 degrees varus post-operatively. Restoration of HKA axis was 0.76 ± 1.9 degrees from intra-operative planning (p < 0.0005). Implant placement accuracy in the coronal plane was 0.08 ± 1.36 degrees (p = 0.458) for the femoral component and 0.71 ± 1.3 degrees (p < 0.0005) for the tibial component. Rotational alignment mean deviation was 0.39 ± 1.49 degrees (p = 0.001). Most patients (98.1%) had ≤ 2 mm difference in extension-flexion gaps. PROM scores showed improvement and exceeded pre-operative scores by 6 weeks post-surgery. Robotic-assisted knee arthroplasty provides precise control over traditionally subjective factors, demonstrating excellent early post-operative outcomes.Level of evidence Prospective observational study-II.

Robotic arthroplasty software training improves understanding of total knee arthroplasty alignment and balancing principles: a randomized controlled trial

Understanding alignment and gap balancing in Total Knee Arthroplasty (TKA) can be challenging for trainee and experienced orthopedic surgeons. Traditional learning methods may not effectively translate to real-life scenarios. The advent of advanced technologies like robotic surgery and navigation systems has revolutionized intraoperative understanding of gap balancing techniques. This trial aims to investigate the effectiveness of robotic TKA planning software in educating trainees about alignment and ligament balancing. We hypothesize that a single session with the software will significantly enhance trainees' understanding of these techniques. This UK-based single-center, two-arm, group parallel randomized controlled trial was conducted during a national robotic arthroplasty symposium. It aims to evaluate the effect of robotic knee arthroplasty software training on understanding TKA alignment and gap balancing principles using Multiple Choice Questions (MCQs). The MCQ test was crafted based on established guidelines from a different institution with expert consensus in the field. Our study revealed that baseline knowledge of gap balancing and alignment principles was generally low among all participants. However, the intervention group, which received comprehensive robotic software training, demonstrated a significant improvement in their MCQ scores compared to the control group, which did not undergo the training. In conclusion, our study demonstrates that robotic arthroplasty software training significantly improves the understanding of TKA alignment and balancing principles among orthopedic trainees. Level of Evidence II.

Utilization and timing of surgical intervention for central cord syndrome in the United States

STUDY DESIGN

Retrospective cohort analysis.

OBJECTIVE

CCS is the most common type of incomplete spinal cord injury and can occur without or with bony injury. Surgical intervention and its timing for patients diagnosed with CCS has been controversial. The current study assessed utilization of and factors associated with operative intervention and its timing in patients diagnosed with central cord syndrome (CCS) in the absence of bony injury.

METHODS

Adult patients diagnosed with CCS in the absence of vertebral fracture were queried from the national, multi-insurance, administrative 2015-2020 M151 PearlDiver database. The incidence, trends, and timing of operative intervention following CCS were assessed. Patient characteristics associated with surgical intervention and its timing were determined.

RESULTS

From 2015 to 2020, 11,653 patients meeting inclusion criteria were identified, of which surgical intervention was identified for 2,003 (17.2%) and thus nonsurgical intervention for 9,650 (82.8%). The proportion of patients undergoing operative intervention evolved from 11.5% in 2015 to 19.7% in 2020 (p < 0.0001). Of those undergoing surgical intervention, the greatest increase was seen for those undergoing surgery within two days of diagnosis (5.5% in 2015 to 12.3% in 2020, p < 0.0001). On multivariable analysis, more recent year of service, region of service, younger age, and higher comorbidity burden were independent predictors of operative management (p < 0.05 for all).

CONCLUSION

The majority of a large cohort of patients with first diagnosis CCS in the absence of bony injury were managed non-operatively. Operative management increased over the years of study, were performed earlier after diagnosis, and varied based on patient characteristic and geographic region.

Fixation options for total knee arthroplasty: a comprehensive literature review

Total knee arthroplasty is a consistently successful, cost-efficient, and highly effective surgical procedure for treating severe knee osteoarthritis. The success and longevity of total knee arthroplasty depend significantly on the fixation method used to secure the prosthetic components. This comprehensive review examines the primary fixation methods (cemented, cementless, and hybrid fixation), analysing their biomechanics, clinical outcomes, advantages, and disadvantages, focusing on recent advances and trends in total knee arthroplasty fixation.

Minimally invasive interventional procedures for osteoarthritis and inflammatory arthritis: A systematic review and meta-analysis

OBJECTIVE

to summarize the evidence on the efficacy of minimally invasive interventional procedures such as radiofrequency ablation (RFA) and transcatheter arterial embolization (TAE) in patients with osteoarthritis or inflammatory arthritis.

METHODS

a literature search was conducted in PubMed and Web of Science databases. Both randomized controlled trials (RCTs) and non-randomized studies of interventions (NRSI) were included. The results were organized according to the treated anatomical site: knee, hip, foot and ankle, shoulder, hand and wrist, sacroiliac joints. Data about treatment efficacy were extracted. The main outcome was change in pain intensity using the 0-10 visual analog scale (VAS) from baseline to 1 month. Additional timepoints at 3, 6 and 12 months were assessed. Change in functional status was evaluated. Pooled estimates were calculated as the mean difference (MD) and 95 % confidence interval relative to baseline. The meta-analyses of RCTs and NRSI were conducted separately.

RESULTS

of the 4599 retrieved articles, 164 were included in the review and, considering all the established timepoints, 111 (38 RCTs and 73 NRSI) were selected for the meta-analysis. Only one article described patients with inflammatory arthritis. In the meta-analysis of RCTs, one month after the procedure, MD in VAS was -3.98 (-4.41 to -3.55; k = 21) for knee RFA, and -3.18 (-3.96 to -2.39; k = 8) for sacroiliac joints RFA. In the meta-analysis of NRSI, MD in VAS was -4.12 (-4.63 to -3.61; k = 23) for knee RFA, -3.84 (-4.77 to -2.92; k = 7) for knee TAE, -4.34 (-4.96 to -3.71; k = 2) for hip RFA, -3.83 (-4.52 to -3.15; k = 3) for shoulder RFA and -4.93 (-5.58 to -4.28; k = 14) for sacroiliac joints RFA. Significant decrease in pain intensity was found also at 3, 6 and 12 months. Additionally, functional status improved at all the assessed timepoints.

CONCLUSION

minimally invasive interventional procedures can improve pain and functional status of patients affected by OA or chronic sacroiliac pain of degenerative origin. Further research is warranted in the field of inflammatory rheumatic diseases.

Adverse events associated with robotic-assistance in total hip arthroplasty: an analysis based on the FDA MAUDE database

BACKGROUND

The Food and Drug Administration (FDA) maintains the Manufacturer and User Facility Device Experience (MAUDE) database for reporting adverse events associated with medical devices, including emerging technologies, such as robotic-assisted total hip arthroplasty (THA). Aim of this study was to evaluate the variation of adverse events associated with robotics in THA.

METHODS

Medical device reports (MDRs) within the MAUDE database were identified between 2017 and 2021. For MDR identification the product class "orthopaedic stereotaxic equipment" and terms associated with THA were used. Individual adverse events were identified and organised by type and consequences, such as patient injury, surgical delay, or conversion to the manual technique.

RESULTS

521 MDRs constituting 546 discrete events were found. The most common reported complication was intraoperative hardware failure (304/546, 55.7%), among which the most common failure was a broken impaction handle/platform (110, 20.1%). Inaccurate cup placement was the second most common reported complication (63, 11.5%). Abandoning the robot occurred in 13.0% (71/521) of reports. A surgical delay was noted in 28% (146/521) of reports, with an average delay of 17.9 (range 1-60) minutes.

CONCLUSIONS

Identifying complications that may occur with robotics in THA is an important first step in preventing adverse events and surgical delays. Database analysis provide an overview of the range of complications.

Mid-term outcomes of total hip arthroplasty in patients younger than 30 years

INTRODUCTION

Total hip arthroplasty (THA) has predominantly been utilized to treat older patients with primary osteoarthritis. However, recent improvements in surgical technique and implant materials have increased implant longevity, making THA a viable option for younger patients (< 30 years old). While trend analyses indicate an expanding utilization of THA in younger patients with non-OA diagnoses, current data on mid- and long-term THA outcomes in this population are limited. This study aims to describe the demographics, perioperative data, and implant survivorship of patients younger than 30 years undergoing THA.

METHODS

A retrospective study across two large urban academic medical institutions identified 135 patients aged < 30 years who underwent 155 primary THAs between 2012 and 2017, with up to 10-year clinical follow-up. Baseline demographics, surgical indications, intraoperative details, and postoperative outcomes were analyzed.

RESULTS

The mean age at surgery was 24.9 years (range 18-29). Osteonecrosis of the femoral head (55.5%), developmental hip dysplasia (28.3%), and arthritis (15.5%) were the primary indications. Most surgeries utilized the posterior approach (64.5%), manual technique (65.8%), and Ceramic-on-Polyethylene articulation (71.6%). Seven patients (4.5%) were readmitted within 90-days of surgery, including three non-orthopedic-related readmissions (1.9%) and four orthopedic-related readmissions (2.6%). Dislocations were reported in two patients (1.3%). There were six all-cause revisions (3.9%), four aseptic (2.6%) and two septic (1.3%). Kaplan-Meier analysis showed 10-year survival from implant retaining reoperation was 98.7%, 10-year survival from all-cause revision was 96.1%, and 10-year survival from aseptic revision was 97.4%.

CONCLUSION

With a 10-year aseptic implant survivorship rate of 97.4%, THA is a reliable surgical intervention for patients younger than 30 years of age who have severe hip pathology. Further studies are warranted for a more comprehensive understanding of mid- and long-term survivorship risk factors in this demanding population, facilitating improved risk assessment and informed surgical decisions.

Non-pulmonary complications of intrathecal morphine administration: a systematic review and meta-analysis with meta-regression

BACKGROUND

Intrathecal morphine provides effective analgesia for a range of operations. However, widespread implementation into clinical practice is hampered by concerns for potential side-effects. We undertook a systematic review, meta-analysis, and meta-regression with the primary objective of determining whether a threshold dose for non-pulmonary complications could be defined and whether an association could be established between dose and complication rates when intrathecal morphine is administered for perioperative or obstetric analgesia.

METHODS

We systematically searched the literature for randomised controlled trials comparing intrathecal morphine vs control in patients undergoing any type of surgery under general or spinal anaesthesia, or women in labour. Primary outcomes were rates of postoperative nausea and vomiting, pruritus, and urinary retention within the first 24 postoperative hours, analysed according to doses (1-100 μg; 101-200 μg; 201-500 μg; >500 μg), type of surgery, and anaesthetic strategy. Trials were excluded if doses were not specified.

RESULTS

Our analysis included 168 trials with 9917 patients. The rates of postoperative nausea and vomiting, pruritus, and urinary retention were significantly increased in the intrathecal morphine group, with an odds ratio (95% confidence interval) of 1.52 (1.29-1.79), P<0.0001; 6.11 (5.25-7.10), P<0.0001; and 1.73 (1.17-2.56), P=0.005, respectively. Meta-regression could not establish an association between dose and rates of non-pulmonary complications. There was no subgroup difference according to surgery for any outcome. The quality of evidence was low (Grading of Recommendations Assessment, Development, and Evaluation [GRADE] system).

CONCLUSIONS

Intrathecal morphine significantly increased postoperative nausea and vomiting, pruritus, and urinary retention after surgery or labour in a dose-independent manner.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO (CRD42023387838).

Is there an increased revision rate due to early tibial component loosening with a modern total knee arthroplasty design? A retrospective analysis from a large volume arthroplasty centre

BACKGROUND

The Attune TKR was introduced in 2011 as a successor to its predicate design The PFC Sigma. However, following reports of early failures, there are ongoing concerns related to increased loosening rates. Given the concerns, this study aimed to compare revision rates of the Attune implant to an established predicate, and other implant designs used in a high-volume arthroplasty center.

METHODS

We identified 10,202 patients who underwent primary cemented TKR at our institution with a minimum of 1 year follow-up, involving 2406 Attune TKR (557 S +), 4642 PFC TKR, 3154 other designs. Primary outcomes were revision for all-causes, aseptic loosening of any component, and aseptic tibial loosening. Kaplan-Meier survival and Cox regression models were used to compare groups. Matched cohorts were selected for radiographic analysis.

RESULTS

308 knees were revised. The Attune cohort had the lowest risk of revision, with a rate of 2.98 per 1000 implant-years while the PFC and All Other Implant groups had a rate of 3.15 and 4.4 respectively. Aseptic loosing was the most common cause for revision, with 76% (65/88) involving the tibia. Survival analysis showed no significant differences between the Attune and other cohorts. Radiolucent lines were detected in 7.1% of the Attune S + group, 6.8% of the standard Attune group, and 6.3% of the PFC group, with no significant differences found between them.

CONCLUSION

This study represents the largest non-registry review of the Attune TKR in comparison to a predicate and other designs. There was no significant increased revision rate for all-cause revision or aseptic loosening, or peri-implant radiolucencies. It appears that increased loosening may not be as concerning as originally thought.

LEVEL OF EVIDENCE

Level III.

Evaluating two implant designs in patients undergoing primary total knee arthroplasty using a novel measure of early optimal recovery: a retrospective observational study

PURPOSE

Quality of care in total knee arthroplasty (TKA) between implants was assessed using a novel composite outcome measure, early optimal recovery (EOR), to indicate ideal clinical outcomes and minimal healthcare resource utilization.

METHODS

Patients that underwent primary TKA in the study group (ATTUNE® Knee System) or control group (LCS® COMPLETE Knee System) were included in this retrospective, single-center study. EOR was defined as no complications, no readmissions, no extra outpatient visits, ≤ 48 h length of hospital stay (LOS), and restored range of motion and pain perception at 3-month follow-up. Multivariate logistic regression was used to compare EOR between the study and control groups. Results were adjusted for differences in baseline characteristics and are presented with 95% confidence intervals (CI). Data were collected from a specialized clinic for elective surgeries in the Netherlands, between January 2017 and December 2020.

RESULTS

A total of 566 patients (62.4% female, mean age 67 years) were included for analysis; 185 patients (32.7%) underwent TKA in the study group. Compared to the control group, patients in the study group had greater probability of achieving EOR (65.8% [95% CI: 55.1-75.2] vs. 38.9% [95% CI: 32.8-45.3]; p < 0.001), a LOS ≤ 48 h (77.2% [95% CI: 67.7-84.5] vs. 61.4% [95% CI: 54.7-67.7]; p < 0.05), and ideal pain perception at 3-month follow-up (93.3% [95% CI: 85.7-97.0] vs. 78.2% [95% CI: 71.0-83.9]; p < 0.05).

CONCLUSION

The study group was associated with a greater probability of achieving EOR versus the control group, suggesting improved quality of care.

Etiology, Outcomes, and Complications of Total Hip Arthroplasty in Younger Patients: A Nationwide Big Data Analysis

Background: This study investigates the rising trend of total hip arthroplasty (THA) in patients under 55 years old, commonly referred to as "younger" THA patients. Traditionally a procedure for older adults with osteoarthritis, THA is increasingly performed on younger patients. Methods: Using data from the Nationwide Inpatient Sample (NIS) from 2016 to 2019, we analyze the factors driving this trend, including the causes of hip issues, patient characteristics, and coexisting medical conditions. The study examines in-hospital mortality, length of stay, post-surgical complications, and hospitalization costs for 231,630 THA patients aged 18-54.9, identified using ICD-10 codes. Results: Statistical analysis revealed that younger patients (aged 18-34.9) had higher rates of chronic anemia, inflammatory bowel disease, sickle cell disorders, connective tissue disorders, and coagulation defects compared to patients aged 35-44.9 and 45-54.9. They also experienced the longest hospital stays (2.08 days) and highest costs ($70,540). Significant odds ratios were found for sickle cell disorders (36.078), coagulation defects (1.566), inflammatory bowel disease (2.582), connective tissue disorders (11.727), hip dislocation (3.447), and blood transfusion (1.488) in younger patients compared to other THA patients. Conclusions: Comprehensive analysis of these unique needs is crucial for optimizing care, tailoring treatment, managing co-existing conditions, and personalizing recovery strategies to improve outcomes and quality of life for younger THA patients.

High Area Deprivation Index is Associated With Not Achieving the Patient-acceptable Symptom State After TKA

BACKGROUND

The Area Deprivation Index (ADI) approximates a patient's relative socioeconomic deprivation. The ADI has been associated with increased healthcare use after TKA, but it is unknown whether there is an association with patient-reported outcome measures (PROMs). Given that a high proportion of patients are dissatisfied with their results after TKA, and the large number of these procedures performed, knowledge of factors associated with PROMs may indicate opportunities to provide support to patients who might benefit from it.

QUESTIONS/PURPOSES

(1) Is the ADI associated with achieving the minimum clinically important difference (MCID) for the Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain, Joint Replacement (JR), and Physical Function (PS) short forms after TKA? (2) Is the ADI associated with achieving the patient-acceptable symptom state (PASS) thresholds for the KOOS pain, JR, and PS short forms?

METHODS

This was a retrospective study of data drawn from a longitudinally maintained database. Between January 2016 and July 2021, a total of 12,239 patients underwent unilateral TKA at a tertiary healthcare center. Of these, 92% (11,213) had available baseline PROM data and were potentially eligible. An additional 21% (2400) of patients were lost before the minimum study follow-up of 1 year or had incomplete data, leaving 79% (8813) for analysis here. The MCID is the smallest change in an outcome score that a patient is likely to perceive as a clinically important improvement, and the PASS refers to the threshold beyond which patients consider their symptoms acceptable and consistent with adequate functioning and well-being. MCIDs were calculated using a distribution-based method. Multivariable logistic regression models were created to investigate the association of ADI with 1-year PROMs while controlling for patient demographic variables. ADI was stratified into quintiles based on their distribution in our sample. Achievement of MCID and PASS thresholds was determined by the improvement between preoperative and 1-year PROMs.

RESULTS

After controlling for patient demographic factors, ADI was not associated with an inability to achieve the MCID for the KOOS pain, KOOS PS, or KOOS JR. A higher ADI was independently associated with an increased risk of inability to achieve the PASS for KOOS pain (for example, the odds ratio of those in the ADI category of 83 to 100 compared with those in the 1 to 32 category was 1.34 [95% confidence interval 1.13 to 1.58]) and KOOS JR (for example, the OR of those in the ADI category of 83 to 100 compared with those in the 1 the 32 category was 1.29 [95% CI 1.10 to 1.53]), but not KOOS PS (for example, the OR of those in the ADI category of 83 to 100 compared with those in the 1 the 32 category was 1.09 [95% CI 0.92 to 1.29]).

CONCLUSION

Our findings suggest that social and economic factors are associated with patients' perceptions of their overall pain and function after TKA, but such factors are not associated with patients' perceptions of their improvement in symptoms. Patients from areas with higher deprivation may be an at-risk population and could benefit from targeted interventions to improve their perception of their healthcare experience, such as through referrals to nonemergent medical transportation and supporting applications to local care coordination services before proceeding with TKA. Future research should investigate the mechanisms underlying why socioeconomic disadvantage is associated with inability to achieve the PASS, but not the MCID, after TKA.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Generalizability of machine learning models predicting 30-day unplanned readmission after primary total knee arthroplasty using a nationally representative database

Unplanned readmission after primary total knee arthroplasty (TKA) costs an average of US $39,000 per episode and negatively impacts patient outcomes. Although predictive machine learning (ML) models show promise for risk stratification in specific populations, existing studies do not address model generalizability. This study aimed to establish the generalizability of previous institutionally developed ML models to predict 30-day readmission following primary TKA using a national database. Data from 424,354 patients from the ACS-NSQIP database was used to develop and validate four ML models to predict 30-day readmission risk after primary TKA. Individual model performance was assessed and compared based on discrimination, accuracy, calibration, and clinical utility. Length of stay (> 2.5 days), body mass index (BMI) (> 33.21 kg/m2), and operation time (> 93 min) were important determinants of 30-day readmission. All ML models demonstrated equally good accuracy, calibration, and discriminatory ability (Brier score, ANN = RF = HGB = NEPLR = 0.03; ANN, slope = 0.90, intercept =  - 0.11; RF, slope = 0.93, intercept =  - 0.12; HGB, slope = 0.90, intercept =  - 0.12; NEPLR, slope = 0.77, intercept = 0.01; AUCANN = AUCRF = AUCHGB = AUCNEPLR = 0.78). This study validates the generalizability of four previously developed ML algorithms in predicting readmission risk in patients undergoing TKA and offers surgeons an opportunity to reduce readmissions by optimizing discharge planning, BMI, and surgical efficiency.

Effects of Vancomycin/Tobramycin-Doped Ceramic Composite (Polyvinyl Alcohol Composite-Vancomycin/Tobramycin-Polymeric Dicalcium Phosphate Dihydrate) in a Rat Femur Model Implanted With Contaminated Porous Titanium Cylinders

BACKGROUND

Periprosthetic joint infection (PJI) remains common and problematic. We hypothesized that using a bioceramic that provided rapid release of the antibiotics (vancomycin [VAN] or VAN and tobramycin [VAN and TOB]) from a polyvinyl-alcohol-composite (PVA) combined with a delayed and sustained antibiotic release from polymeric-dicalcium-phosphate-dihydrate (PDCPD) ceramic would inhibit S. aureus-associated implant infections.

METHODS

A total of 50 male Sprague Dawley rats were randomly divided into 5 groups-I: negative control; II: bacteria only; III: bacteria + saline wash; IV: bacteria + PVA-VAN-PDCPD, and V: bacteria + PVA-VAN-TOB-PDCPD. A porous titanium (Ti) implant was press-fit into the rat knee. S. aureus-containing broth was added into the joint space creating a PJI. After 1 week, the joints from groups III to V were washed with saline and the fluid collected for bacterial quantification. This was followed by saline irrigation treatment (groups III to V) and application of the antibiotic-loaded PVA-PDCPD bioceramic (groups IV and V). On day 21, joint fluid was collected, and the implants harvested for bacterial quantification.

RESULTS

No bacteria were isolated from the negative control (group I). The positive control (group II) was positive on both days 7 and 21. Bacteria were still present on day 21 in the fluid and implant in group III. Groups (IV and V) showed a decrease in the bacterial burden in the fluid and implant on day 21. There were significant differences in bacteria levels in the collected wash fluid and on the implant at day 21 between the saline wash (group III) and treatment groups (IV and V).

CONCLUSIONS

In this animal model of acute periprosthetic infection, treatment with PVA-VAN-PDCPD and PVA-VAN/TOB-PDCPD reduced bacterial load in the infected joint and the infected Ti implant. Application of PVA-VAN-PDCPD and/or PVA-VAN/TOB-PDCPD after saline irrigation could be used as an addition to the treatment of PJI.

Who Are the Anatomic Outliers Undergoing Total Knee Arthroplasty? A Computed Tomography-Based Analysis of the Hip-Knee-Ankle Axis Across 1,352 Preoperative Computed Tomographies Using a Deep Learning and Computer Vision-Based Pipeline

BACKGROUND

Dissatisfaction after total knee arthroplasty (TKA) ranges from 15 to 30%. While patient selection may be partially responsible, morphological and reconstructive challenges may be determinants. Preoperative computed tomography (CT) scans for TKA planning allow us to evaluate the hip-knee-ankle axis and establish a baseline phenotypic distribution across anatomic parameters. The purpose of this cross-sectional analysis was to establish the distributions of 27 parameters in a pre-TKA cohort and perform threshold analysis to identify anatomic outliers.

METHODS

There were 1,352 pre-TKA CTs that were processed. A 2-step deep learning pipeline of classification and segmentation models identified landmark images and then generated contour representations. We used an open-source computer vision library to compute measurements for 27 anatomic metrics along the hip-knee axis. Normative distribution plots were established, and thresholds for the 15th percentile at both extremes were calculated. Metrics falling outside the central 70th percentile were considered outlier indices. A threshold analysis of outlier indices against the proportion of the cohort was performed.

RESULTS

Significant variation exists in pre-TKA anatomy across 27 normally distributed metrics. Threshold analysis revealed a sigmoid function with a critical point at 9 outlier indices, representing 31.2% of subjects as anatomic outliers. Metrics with the greatest variation related to deformity (tibiofemoral angle, medial proximal tibial angle, lateral distal femoral angle), bony size (tibial width, anteroposterior femoral size, femoral head size, medial femoral condyle size), intraoperative landmarks (posterior tibial slope, transepicondylar and posterior condylar axes), and neglected rotational considerations (acetabular and femoral version, femoral torsion).

CONCLUSIONS

In the largest non-industry database of pre-TKA CTs using a fully automated 3-stage deep learning and computer vision-based pipeline, marked anatomic variation exists. In the pursuit of understanding the dissatisfaction rate after TKA, acknowledging that 31% of patients represent anatomic outliers may help us better achieve anatomically personalized TKA, with or without adjunctive technology.

Bone cement in total hip arthroplasty - Is it really green?

BACKGROUND

Total hip replacement (THR)is typically cemented, cementless or hybrid depending on patient factors and surgeon preference. To date no studies have evaluated waste generated with each of these procedures in relation to implant choice, and particularly waste related to consumables. We aimed to quantify the volume; type and ability to recycle this waste and suggest potential strategies for reducing the overall waste related to consumables in THR.

METHOD

This was a prospective review of all waste related to consumables in THR. The waste was weighed using a Salter 1066 BKDR15 scale, accurate to the nearest 1 ​g. The primary outcome was the amount of waste generated per case depending on implant choice (cemented vs. uncemented). Secondary outcomes included: proportion of clinical waste and proportion of recyclable waste.

RESULTS

Cemented THR generated a total of 1.89 ​kg of waste compared to 775 ​g for an uncemented THR. Cemented THR generated significantly more sterile (hazardous) waste than uncemented THR both as overall volume and as a proportion 763 ​g (40%) vs 76 ​g (10%). Significantly more of the waste related to uncemented THR was amenable to being recycled through conventional waste streams with simple changes in theatre 672 ​g (86%) compared to 989 ​g (52%) with cemented THR. Between 20 and 30% of waste packaging for both types of surgery compromised information booklets.

CONCLUSION

Cemented hip replacement generates significantly more waste from consumables than uncemented and a greater amount of this waste is hazardous requiring intensive processing. For both implants a significant proportion of waste can be recycled with simple process changes in theatre. Industry partners have a responsibility to minimise unnecessary packaging and work with surgeons to improve sustainability.

Enhanced recovery program in ambulatory pediatric urology: A quality improvement initiative

BACKGROUND

Enhanced Recovery After Surgery (ERAS) was established in 2001 for adult patients undergoing complex procedures. ERAS in adult ambulatory surgery later followed with similar positive outcomes. For the pediatric population, ERAS implementation has shown promising results in complex surgeries such as bladder reconstruction. Its application in pediatric ambulatory surgery has only recently been reported. We hereby report a Quality Improvement initiative in implementing an Enhanced Recovery Protocol (ERP) for pediatric urology in an ambulatory surgery center.

METHODS

A project was launched to evaluate and implement enhanced recovery elements into an institutional Enhanced Recovery Protocol (ERP). These included reliance on peripheral nerve blocks for all inguinal and genital cases and reduction of opioids intraoperatively and postoperatively. Improvements were placed into a project plan broken into one preparation phase to collect baseline data and three implementation phases to enhance existing and implement new elements. The implementation phase went through iterative Plan-Do-Study-Act (PDSA) cycles for all sub-projects. Team countermeasures were based on available evidence. A consensus process was used to resolve disagreement. Monthly meetings were held to share real-time data, gather new feedback, and modify plans as needed. The primary outcome measures selected were percent intraoperative opioid use, percent opioid prescribing, mean PACU length of stay, and average number of opioid doses prescribed. Secondary outcome measures were mean maximum pain score in PACU, PACU rescue rate for PONV, and patient/family satisfaction scores. Post-implementation data for 18 months was included for evaluation. Statistical process control methodology was used.

RESULTS

The total number of participants was 3306: 561 (baseline), 220 (Phase 1) 356 (Phase 2) and 527 (Phase 3), 1642 (post-implementation). Intraoperative opioid use was eliminated in >99% of cases. Post-operative opioid prescribing was reduced from 30% to 15% of patients. The number of opioid doses was also reduced from an average of 7.6 to 6.1 doses. There was no change for the mean maximum pain score in the recovery room despite elimination of opioids. Patient/family satisfaction scores were high and sustained throughout the period of study (9.8/10). Balancing measures such as return to the operating room within 30 days and return to the emergency department within 7 days were unchanged.

CONCLUSIONS

This QI project demonstrated the feasibility of a pediatric enhanced recovery protocol in a urology ambulatory surgery setting. With implementation of this protocol, intraoperative opioid use was virtually eliminated, and opioid prescribing was reduced without affecting pain scores or post-operative complications.

Neglected Anterior Dislocation of Hip Managed with Total Hip Arthroplasty Using Dual Approach: A Case Report and Review of Literature

Introduction

Traumatic hip dislocations frequently result from road traffic accidents and are prevalent in developing nations. Untreated dislocations either due to ignorance or lack of proper treatment become more challenging to manage and have an increased likelihood of developing avascular necrosis (AVN). Over time, closed methods of reduction become impractical, and if the waiting period surpasses 3 months, open reduction likewise becomes unworkable. Anterior dislocations are less common than posterior dislocations, accounting for a frequency of 7-13% of all hip dislocations. Neglected anterior hip dislocations are extremely rare, and therefore, there is a paucity of information about the management of these dislocations and associated injuries. The available treatment options for these particular situations are total hip arthroplasty (THA), Girdlestone surgery, or hip arthrodesis.

Case Report

We describe the case of a 49-year-old male who presented to our hospital with a neglected anterior dislocation of the hip. The patient disclosed a history of hip trauma 8 months ago, initially receiving conservative management. However, due to persistent pain and functional limitations, he sought further medical attention. A physical examination, radiographic evaluation, and computed tomography (CT) scan confirmed the diagnosis. The patient underwent THA using dual anterior and posterior approaches, followed by a comprehensive rehabilitation program.

Conclusion

Anterior dislocation of the hip is a relatively rare condition, and its neglected presentation is even rarer. This case highlights the importance of prompt diagnosis and early intervention in neglected anterior hip dislocations to minimize complications and optimize patient outcomes.

Racial and Ethnic Disparities in Providing Guideline-Concordant Care After Hip Fracture Surgery

Importance

Institutions have adopted protocol-driven standardized hip fracture programs (SHFPs). However, concerns persist regarding bias in adherence to guideline-concordant care leading to disparities in implementing high-quality care for patients recovering from surgery for hip fracture.

Objective

To assess disparities in the implementation of guideline-concordant care for patients after hip fracture surgery in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) Targeted Hip Fracture (THF) Database.

Design, Setting, and Participants

This cross-sectional study was conducted using the ACS-NSQIP THF database from 2016 to 2021 for patients aged 65 years and older with hip fractures undergoing surgical fixation. Care outcomes of racial and ethnic minority patients (including American Indian or Alaska Native, Asian, Black or African American, Native Hawaiian or Pacific Islander, or multiple races and Hispanic ethnicity) were compared with non-Hispanic White patients via risk difference, stratified by care institution SHFP status. Modified Poisson regression was used to measure interactions. Statistical analysis was performed from November 2022 to June 2024.

Main Outcomes and Measures

The primary outcomes of interest encompassed weight-bearing as tolerated (WBAT) on postoperative day 1 (POD1), venous thromboembolism (VTE) prophylaxis, bone-protective medication, and the presence of SHFP at the institution.

Results

Among 62 194 patients (mean [SD] age, 82.4 [7.3] years; 43 356 [69.7%] female) who met inclusion criteria and after multiple imputation, 11.2% (95% CI, 10.8%-11.5%) were racial and ethnic minority patients, 3.3% (95% CI, 3.1%-3.4%) were Hispanic patients, and 92.0% (95% CI, 91.7%-92.2%) were White. Receiving care at an institution with an SHFP was associated with improved likelihood of receiving guideline-concordant care for all patients to varying degrees across care outcomes. SHFP was associated with higher probability of being WBAT-POD1 (risk difference for racial and ethnic minority patients, 0.030 [95% CI, 0.004-0.056]; risk difference for non-Hispanic White patients, 0.037 [95% CI, 0.029-0.45]) and being prescribed VTE prophylaxis (risk difference for racial and ethnic minority patients, 0.066 [95% CI, 0.040-0.093]; risk difference for non-Hispanic White patients, 0.080 [95% CI, 0.071-0.089]), but SHFP was associated with the largest improvements in receipt of bone-protective medications (risk difference for racial and ethnic minority patients, 0.149 [95% CI, 0.121-0.178]; risk difference for non-Hispanic White patients, 0.181 [95% CI, 0.173-0.190]). While receiving care at an SHFP was associated with improved probability of receiving guideline-concordant care in both race and ethnicity groups, greater improvements were seen among non-Hispanic White patients compared with racial and ethnic minority patients.

Conclusions and Relevance

Older adults who received care at an institution with an SHFP were more likely to receive guideline-concordant care (bone-protective medication, WBAT-POD1, and VTE prophylaxis), regardless of race and ethnicity. However, the probability of receiving guideline-concordant care at an institution with an SHFP increased more for non-Hispanic White patients than racial and ethnic minority patients.

Synovial Calprotectin is Superior to Synovial Leukocyte Count in Excluding Chronic Periprosthetic Joint Infections, a Retrospective Cohort Study

BACKGROUND

Synovial calprotectin is a promising biomarker for diagnosing chronic periprosthetic joint infections (PJIs), but its diagnostic value has not been directly compared to synovial leukocyte count and polymorphonuclear neutrophils. This study aimed to: (1) evaluate and compare the diagnostic accuracy between these markers in patients undergoing revision arthroplasty for chronic PJI or aseptic reasons; and (2) determine the best rule-out and rule-in test for PJI.

METHODS

Synovial fluid samples from patients undergoing revision arthroplasty in hip and knee joints were collected and analyzed. Patients diagnosed with an acute PJI, patients treated with antibiotics 2 weeks prior to revision surgery, and/or patients who had active inflammatory joint disease were excluded. Periprosthetic joint infections were diagnosed based on the presence of a sinus tract and/or positive intraoperative cultures according to the European Bone and Joint Infection Society microbiological criteria.

RESULTS

A total of 137 patients were included, of whom 19 (14%) were diagnosed with a PJI. Overall, synovial calprotectin had the highest diagnostic accuracy of all studied markers (area under the curve 96%). Synovial calprotectin, with a cutoff of 50 mg/L, had the highest negative predictive value of 100%. However, PMNs (> 80%) combined with a leukocyte count (> 3,000 cells/μL) showed the highest positive likelihood ratio of an infection (PLR 17).

CONCLUSIONS

Synovial calprotectin is the most accurate biomarker for ruling out a chronic PJI, while the combination of synovial leukocyte count and PMN is most reliable for ruling in a chronic PJI.

Surgery Within 24 Hours Reduces Mortality and General Complication Rates in Patients Who Have Periprosthetic Femoral Fractures at the Hip

BACKGROUND

In patients who have hip fractures, treatment within 24 hours reduces mortality and complication rates. A similar relationship can be assumed for patients who have hip periprosthetic femoral fractures (PPFs) owing to the similar baseline characteristics of the patient populations. This monocentric retrospective study aimed to compare the complication and mortality rates in patients who had hip PPF treated within and after 24 hours.

METHODS

In total, 350 consecutive patients who had hip PPF in a maximum-care arthroplasty and trauma center between 2006 and 2020 were retrospectively evaluated. The cases were divided into 2 groups using a time to surgery (TTS) of 24 hours as the cutoff value. The primary outcome variables were operative and general complications as well as mortalities within 1 year.

RESULTS

Overall, the mean TTS was 1.4 days, and the 1-year mortality was 14.6%. The TTS ≤ 24 hours (n = 166) and TTS > 24 hours (n = 184) groups were comparable in terms of baseline characteristics and comorbidities. Surgical complications were equally frequent in the 2 groups (16.3 versus 15.2%, P = .883). General complications occurred significantly more often in the late patient care group (11.4 versus 28.3%, P < .001). In addition, the 30-day mortality (0.6 versus 5.5%, P = .012), and 1-year mortality (8.3 versus 20.5%, P = .003) rates significantly increased in patients who had TTS > 24 hours. Cox regression analysis yielded a hazard ratio of 4.385 (P < .001) for the TTS > 24 hours group.

CONCLUSIONS

Prompt treatment is required for patients who have hip PPF to reduce mortality and overall complications.

Unexpected positive cultures in revision total knee arthroplasty after unicompartmental knee arthroplasty

PURPOSE

Unexpected positive cultures are defined as a single positive culture in intraoperative samples taken during revision surgery after prosthetic joint infection was preoperatively ruled out. This study aims to determine the prevalence of unexpected positive cultures (UPC) in revision total knee arthroplasty (TKA) after unicompartmental knee arthroplasty (UKA). As a secondary objective, this study aims to compare the re-intervention rate in this specific group, between UPC and non-UPC patients. The hypothesis is that the UPC prevalence in patients who undergo a revision TKA after UKA is not higher than in other TKA revision cases and this does not increase the risk of re-intervention.

METHODS

This is a retrospective study where all patients who underwent a UKA revision from January 2016 to February 2023 in a high-volume arthroplasty centre, were analyzed. Unexpected positive culture prevalence in this group of patients was obtained.

RESULTS

During the included period, 270 UKA revision surgeries were performed. Eight cases had at least two positive cultures and were therefore excluded. The final analysis included 262 patients. Of these, 8 (3.05%) patients presented UPCs and the isolated microorganisms were low-virulence organisms. None of the UPC patients received any treatment. No statistical differences were found between UPC and non-UPC groups in the analyzed variables.

CONCLUSION

The prevalence of unexpected positive cultures in patients following revision of unicompartmental knee arthroplasty is lower than in patients who undergo a revision of total knee arthroplasty. In UKA patients a UPC does not seem to increase the risk of a re-intervention, so it can be safely ignored if ICM criteria are not met.

Osseointegration of minimally invasive sacroiliac joint fixation implants-A human retrieval study

Minimally invasive sacroiliac joint fusion has become increasingly prevalent and is described to reduce pain and improve function. In some patients, pain can recur several months after primary surgery. Lack of early implant osseointegration might be a cause of pain and hence an indication for revision surgery. Triangular titanium implants are the most documented implant for minimally invasive sacroiliac joint fusion. There is, however, no knowledge of how triangular titanium implants osseointegrate in humans and whether fusion is induced over the sacroiliac joint. During planned revision surgery due to recurrent pain, six triangular titanium implants were retrieved from six different patients at median 9 months from primary surgery. All six implants were scanned using microcomputed tomography. The presence or absence of bone in-growth, on-growth, and through-growth of the implants was evaluated as an indication of implant osseointegration. Three of six implants showed no or minor signs of osseointegration. Of the three remaining implants, one showed partial osseointegration and two implants showed high degrees of osseointegration. This study showed that triangular titanium implants can osseointegrate into host bone in humans. When osseointegration occurs, triangular titanium implants can give fusion across the sacroiliac joint.

Use of blood parameters for the prediction of mortality in patients with below‑knee amputation

The present retrospective study aimed to investigate the value of blood parameters in predicting mortality in patients with below-knee amputation (BKA). A total of 178 patients with BKA were included in the present study. The patients were divided into two groups, namely the exitus group (n=136; 76.4%) and the survivors group (n=42; 23.6%). Patients in the exitus group were further divided into three subgroups: i) Those who experienced mortality in <1 month (n=55; 40.4%); ii) those who experienced mortality between 1-12 months (n=48; 35.3%); and iii) those who experienced mortality in >12 months after surgery (n=33; 24.3%). Binary logistic regression and a generalized linear model were used for relational analysis, and a receiver operator characteristic curve was used for diagnostic tests. It was found that the parameters of age (B=0.061; P=0.01), eosinophil-to-lymphocyte ratio (ELR) (B=-2.861; P<0.05), C-reactive protein (CRP)/albumin ratio (B=0.027; P<0.01) and mean platelet volume (MPV)/lymphocyte ratio (B=0.310; P<0.01) had a significant effect on mortality at the multivariate level. Moreover, regression coefficients showed that the effect of age, CRP/albumin and MPV/lymphocyte ratios on mortality were positive, whereas the effect of the ELR was negative. The mortality predictive values of age [area under the curve (AUC)=0.681; P=0.01], ELR (AUC=0.630; P=0.01), CRP/albumin ratio (AUC=0.746; P=0.01) and MPV/lymphocyte ratio (AUC=0.676; P<0.01) were also found to be statistically significant. For the 27.51 CRP/albumin cut-off value, the sensitivity was found to be 80.1%, whereas the specificity was 54.8%. For the 36.93 CRP/albumin cut-off value, the sensitivity was 71.3%, and the specificity was 73.8%. Furthermore, MPV (B=-0.37; P<0.01) and hemoglobin/red-blood-cell distribution width (RDW) ratio (B=5.20; P<0.01) were found to have a significant effect on the time to death at the multivariate level. The parameters MPV (AUC=0.648; P<0.01) and hemoglobin/RDW (AUC=0.673; P=0.01) had predictive value in terms of the time to death. The predictive value for MPV was found to be 64.8%, whereas that for the hemoglobin/RDW ratio was 67.3%. For the 0.54 cut-off value for hemoglobin/RDW, the sensitivity was 74.5%, and the specificity was 11.1%. By contrast, for the 0.84 cut-off value for the hemoglobin/RDW ratio, the sensitivity was 10.9% and the specificity was 81.5%. In conclusion, the CRP/albumin ratio was identified as a significant mortality parameter, whereas the hemoglobin/RDW ratio was a significant time to death predictor, according to the results of the present analysis. These results may guide clinical practices and further research in terms of predicting mortality in patients with BKA.

Risk factors for infection in patients undergoing shoulder arthroscopy: a systematic review and meta-analysis

We conducted a meta-analysis to determine the risk of infection following shoulder arthroscopy and to identify risk factors for infection. We systematically searched the PubMed/Medline, Embase and Cochrane Library databases, as well as the reference lists of previous systematic reviews and meta-analyses; manual searches were also performed. A random-effects model was employed to estimate pooled odds ratios (ORs), based on sample size, the P-value of Egger's test and heterogeneity among studies. Of the 29,342 articles screened, 16 retrospective studies comprising 74,759 patients were included. High-quality evidence showed that patients with diabetes (OR, 1.30; 95% confidence interval (CI), 1.20-1.41) or hypertension (OR, 1.26; 95% CI, 1.10-1.44) had a higher risk of infection, while moderate quality evidence showed that patients with obesity (body mass index ≥30 kg/m2) (OR, 1.42; 95% CI, 1.28-1.57), those who were male (OR, 1.65; 95% CI, 1.12-2.44), those who had an American Society of Anesthesiologists (ASA) class ≥3 (OR, 2.02; 95% CI, 1.02-3.99) and those who had a history of smoking (OR, 2.44; 95% CI, 1.39-4.28) had a higher risk of infection. The meta-analysis revealed that there was no association between age, time of surgery, or alcohol consumption and infection. This meta-analysis identified six significant risk factors for infection following shoulder arthroscopy including diabetes, obesity, hypertension, male sex, ASA class, history of smoking. These patient-related risk factors may help identify postoperative patients at higher risk for infection following shoulder arthroscopy.

Total Hip Arthroplasty Outcomes in Patients with Gout: A Retrospective Analysis of Matched Large Cohorts

Background

Gout is the most prevalent form of inflammatory arthritis in the world. Total hip arthroplasty (THA) has emerged as a widely sought-after and highly effective surgical procedure for advanced hip diseases. However, there is a lack of research on the impact of gout on primary THA outcomes in large cohorts. This study aimed to address this gap by primarily investigating complications following THA in patients with or without gout.

Methods

Patients with records of gout in the 2 years leading up to their primary THA and who also have at least 2 years of follow-up were identified using a national insurance database and compared to a 5:1 matched control. A total of 32,466 patients with gout and 161,514 patients without gout undergoing THA were identified. Multivariable logistic regression analyses were done for medical complications up to 90 days and surgical complications up to 2 years. In addition, 90-day emergency department (ED) visits and inpatient readmission were also documented.

Results

Patients with gout demonstrated higher rates of medical complications including deep vein thrombosis, transfusion, acute kidney injury, and urinary tract infection than non-gout patients (p < 0.001). Gout patients also showed higher rates of pulmonary embolism (p = 0.017). Increased incidences of surgical complications were identified in gout patients, specifically wound complications and periprosthetic joint infection (p < 0.001). There was an increased risk of revision for gout patients up to 90 days (p = 0.003), 1 year (p = 0.027), and 2 years (p = 0.039). There was also an increased risk of dislocation for gout patients up to 90 days (p = 0.022) and 1 year (p = 0.047), but not at 2 years. No significant difference was observed in aseptic loosening or periprosthetic fracture. Additionally, gout patients also demonstrated a higher likelihood of 90-day ED visits and readmission (p < 0.001).

Conclusions

Primary THA in gout patients is associated with increased risks of multiple medical and surgical complications. Our findings provide insights into the planning and expectation of THA for patients with gout. These insights have the potential to benefit the decision-making process for gout patients considering THA.

Multiplex cytokine analysis for the identification of novel potential synovial fluid biomarkers for periprosthetic joint infections

INTRODUCTION

Periprosthetic joint infections (PJIs) are a devastating complication of total hip (THA) and knee (TKA) arthroplasty. The use of novel techniques like multiplex cytokine analysis could contribute immensely to the identification of potential novel biomarkers.

PATIENTS AND METHODS

This is a single-centre study of patients that were treated with revision TKA, THA or hemiarthroplasty. Serum's white blood cells (WBCs), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) and synovial fluid's WBCs, percentage of polymorphonuclear neutrophils (%PMNs) and CRP were measured. Proteomic analysis targeting the secreted cytokines in synovial fluid was conducted using a 73-plex assay panel. The results were statistically compared between the septic and aseptic cases and ROC analysis to establish the area under the curve (AUC), sensitivity and specificity of each biomarker.

RESULTS

The study included 30 patients (18 revision THA cases; 3 conversion of hemiarthroplasty to THA and 9 revision TKA cases); 14 cases were considered infected, 1 likely infected and 15 not infected. The results showed statistically significant differences (p < 0.05) between infected and not infected cases in serum's ESR, CRP and synovial fluid's%PMNs, growth-regulated oncogene alpha (GROA), interleukin-8, interleukin-5, S100-A8/calprotectin and resistin (RETN) with AUCs of 0.75, 0.72, 0.95, 0.75, 0.72, 0.95, 0.83, 0.73, 0.75, 0.81 and 0.76 respectively.

CONCLUSIONS

In the present study, serum ESR and CRP as well as synovial %PMNs, GROA, IL-8, IL-5, calprotectin and RETN protein levels were identified as potential biomarkers. Further studies are needed to further investigate their diagnostic utility and optimal cut-off values.

Intraoperative Surgeon-Administered Adductor Canal Block Is a Safe Alternative to Preoperative Anesthesiologist-Administered Adductor Canal Block in Primary Total Knee Arthroplasty

BACKGROUND

The shift toward outpatient total knee arthroplasties (TKAs) has led to a demand for effective perioperative pain control methods. A surgeon-performed "low" adductor canal block ("low-ACB") technique, involving an intraoperative ACB, is gaining popularity due to its efficiency and early pain control potential. This study examined the transition from traditional preoperative anesthesiologist-performed ultrasound-guided adductor canal blocks ("high-ACB") to low-ACB, evaluating pain control, morphine consumption, first physical therapy visit gait distance, hospital length-of-stay, and complications.

METHODS

There were 2,620 patients at a single institution who underwent a primary total knee arthroplasty between January 1, 2019, and December 31, 2022, and received either a low-ACB or high-ACB. Cohorts included 1,248 patients and 1,372 patients in the low-ACB and high-ACB groups, respectively. Demographics and operative times were similar. Patient characteristics and outcomes such as morphine milligram equivalents (MMEs), Visual Analog Scale pain scores, gait distance (feet), length of stay (days), and postoperative complications (30-day readmission and 30-day emergency department visit) were collected.

RESULTS

The low-ACB cohort had higher pain scores over the first 24 hours (5.05 versus 4.86, P < .001) and higher MME at 6 hours (11.49 versus 8.99, P < .001), although this was not clinically significant. There was no difference in pain scores or MME at 12 or 24 hours (20.81 versus 22.07 and 44.67 versus 48.78, respectively). The low-ACB cohort showed longer gait distance at the first physical therapy visit (188.5 versus 165.1 feet, P < .001) and a shorter length of stay (0.88 versus 1.46 days, P < .01), but these were not clinically significant. There were no differences in 30-day complications.

CONCLUSIONS

The low-ACB offers effective pain relief and comparable early recovery without increasing operative time or the complication rate. Low-ACB is an effective, safe, and economical alternative to high-ACB.

LEVEL OF EVIDENCE

Therapeutic study, Level III (retrospective cohort study).

Effect of Posterior Cruciate Ligament Resection on Gap Balancing in Robot-assisted Total Knee Arthroplasty

OBJECTIVE

Retention or sacrifice of the posterior cruciate ligament (PCL) is one of the most controversial issues while performing total knee arthroplasty (TKA). This study aimed to evaluate the impact of PCL resection on flexion-extension gaps, femoral component rotation, and bone resection amounts during robot-assisted TKA.

METHODS

This prospective study included 40 patients with knee osteoarthritis who underwent robot-assisted posterior-stabilized (PS) TKA between September 2021 and February 2022. Of the patients, 75% were women (30/40) with a mean age and BMI of 72.6 years and 27.4 kg/m2, respectively. The guidance module and camera stand assembly were used to capture gaps before and after PCL resection. Measurements of femoral component rotation and bone resection amounts were made in cruciate-retaining (CR) TKA mode and PS-TKA mode.

RESULTS

After PCL resection, the mean change in the medial and lateral compartments of flexion gaps increased by 2.0 and 0.6 mm, respectively (p < 0.001). Compared with the CR-TKA mode group, the bone resection amounts of the medial posterior condyle and the lateral posterior condyle in the PS-TKA mode group decreased by 2.0 ± 1.1 and 1.1 ± 1.1 mm, respectively, and the external rotation of the femoral prosthesis relative to the posterior condylar axis and trans-epicondylar line was reduced by 1.0° ± 1.3° and 1.2° ± 1.6°, respectively (p < 0.001).

CONCLUSION

The release of the PCL did not affect the extension gap, but significantly increased the flexion gap. Moreover, the increases in the medial flexion gap were greater than those of the lateral flexion gap. After PCL resection, less external rotation of the femoral prosthesis and fewer bone cuts of the posterior femur were needed in PS-TKA.

Existing and Novel Assessment Methods for Metal Sensitivity in Elective Lower-Limb Arthroplasty-A Scoping Review

Background

Metal sensitivity is a possible cause for revision in elective lower-limb arthroplasty. This scoping review aims to identify and evaluate all existing and novel assessment methods for metal sensitivity in elective lower-limb arthroplasty.

Methods

The Cochrane Central Register of Controlled Trials (CENTRAL), Ovid Medical Literature Analysis and Retrieval System Online (MEDLINE), PubMed, and Google Scholar databases were searched for studies published between January 1, 2000, and September 1, 2023. Studies evaluating one or more metal sensitivity assessment method preoperatively, perioperatively, or postoperatively were included. Studies were grouped based on the assessment methods reported and summarized based on the study design, outcome measure, results, and comments on the method's validity.

Results

A total of 1220 results were screened, with 39 results (15 retrospective cohort studies, 11 prospective cohort studies, 6 case reports, 5 randomized controlled trials, and 2 case control studies) included, identifying 12 assessment methods. The most used one was patch testing, featuring in 17 studies (43.6%). Lymphocyte transformation assay/testing featured in 12 studies (30.8%). Plasma/serum concentration of metal ions featured in 6 studies (15.4%). Patient history and serum cytokine testing featured in 7 (17.9%) and 4 (10.3%) studies each. Generalized serum inflammatory markers featured in 3 studies (7.7%). The remaining 6 methods each featured in one or 2 studies. Evidence of the reliability of most metrics was limited.

Conclusions

Several assessment methods were identified. However, evidence of any methods reliably predicting and diagnosing the occurrence of metal sensitivity was limited. There is a need for improved metrics of metal hypersensitivity.

Translation, cross-cultural adaptation, and validation of the Persian version of the Hospital for Special Surgery Anterior Cruciate Ligament Postoperative Satisfaction Survey

PURPOSE

With over 140 million speakers spread across Iran, Afghanistan, and Tajikistan, Persian, also known as Farsi, is a pluri-centric language. The purpose of this study is to perform cross-cultural adaptation and examine the validity and reliability of the Persian translation of the Hospital for Special Surgery Anterior Cruciate Ligament Post-Operative Satisfaction Survey (HSS ACL-SS).

METHODS

In this retrospective study, 102 anterior cruciate ligament reconstruction (ACLR) patients were asked to complete the Persian version of the HSS ACL-SS, Tegner scale, Lysholm score, the Single Assessment Numeric Evaluation (SANE) score, the Cincinnati Knee Rating System (CKRS), and the Visual Analogue Scale (VAS) for pain. Internal consistency was calculated via Cronbach's alpha coefficient. Validity was assessed with the correlations of Spearman's rho. 18 patients were included in the test-retest reliability assessment. The floor and ceiling effects of the examined content validity of HSS ACL-SS.

RESULTS

The Cronbach's alpha coefficient was computed at 0.959, showing outstanding internal consistency. The intra-class correlation coefficient (ICC) demonstrated excellent results (0.986, P-value < 0.001). Insignificant ceiling effects (2.9%) and floor effects (3.9%) were detected. The Persian version of the HSS ACL-SS score significantly correlated with the SANE (r = 0.730, p < 0.001), Lysholm score (r = 0.622, p < 0.001), and CKRS (r = 0.741, p < 0.001).

CONCLUSION

The overall performance of the Persian HSS ACL-SS was more than excellent in terms of reliability and validity. To conclude, Persian HSS ACL-SS may be used to assist patients in having a better perception of post-operative satisfaction.

Intramedullary Total Femur via a Direct Anterior Approach for Complex Revision Total Hip and Knee Arthroplasty

Total femur replacement is a well-recognized salvage procedure and an alternative to hip disarticulation in patients with massive femoral bone loss. Compared to conventional total femur replacement, intramedullary total femur (IMTF) requires less soft tissue dissection and preserves femoral bone stock and soft-tissue attachments. Despite these advantages, patients can still anticipate compromised functional outcomes and high complication rates following IMTF. Prior studies describe IMTF with the patient positioned laterally and utilizing posterior or anterolateral approaches to the hip. We describe our IMTF technique performed via the direct anterior approach in the supine position. In our experience, this is an effective method, with potential benefits including intraoperative limb length and rotational assessment, use of fluoroscopy, more convenient exposure of the knee, and potential lower rates of hip instability.

Evaluation of Adult Reconstruction and Arthroplasty Fellowships in the United States Based on Academic Productivity

Background

Institutional academic productivity varies on an individual level. This study aims to analyze the research output of adult reconstruction and arthroplasty fellowship programs in the United States.

Methods

The American Association of Hip and Knee Surgeons Fellowship Directory was used to evaluate 112 adult reconstruction and arthroplasty fellowships in the United States. Publication data and Hirsch index (h-index) were collected from the Scopus Database. All of each author's total publications were analyzed with their current institution, regardless of their affiliation at the time of publication. Multivariate logistic regressions were performed to determine the effect of program size on research productivity.

Results

The total number of publications per institution ranged from 2 to 3743, with a mean of 289 and a median of 135. The h-index of individual faculty members ranged from 0 to 103, with a mean of 16 and a median of 11. The number of faculty (P < .001) and number of fellows (P = .003) per program had a significant effect on the total number of publications. The number of faculty did not have a significant effect on the median number of publications (P = .12) or the median h-index (P = .31). The number of fellows had a significant effect on the median number of publications (P < .001) and the median h-index (P < .001).

Conclusions

Academic productivity in adult reconstruction and arthroplasty fellowships within the United States varies widely, with the top few institutions responsible for a majority of the overall output.

Outcomes Following Total Hip Arthroplasty in Patients Who Have Von Willebrand Disease Depend on Postoperative Anticoagulation

BACKGROUND

Von Willebrand disease (VWD) is the most common congenital bleeding disorder. This autosomal dominant condition arises from quantitative or qualitative defects of Von Willebrand factor. To our knowledge, this study leveraged a national database to characterize the largest VWD cohort of total hip arthroplasty (THA) patients to date, assessing 90-day postoperative adverse events and 5-year revision-free survival.

METHODS

Adult patients who underwent primary THA for osteoarthritis were identified from January 2010 to October 2021 in a nationwide database. Patients who had and did not have VWD were matched (4:1) on age, sex, and Elixhauser Comorbidity Index and compared with multivariable logistic regression. Patients were then categorized based upon venous thromboembolism (VTE) chemoprophylaxis prescription patterns to compare bleeding and thrombotic adverse events.

RESULTS

Of 544,851 THA patients, VWD was identified in 309 patients (0.06%). The matched cohorts contained 1,221 patients who did not have VWD and 306 patients who have VWD. On multivariable analysis, VWD patients had increased odds of 90-day VTE (odds ratio [OR] = 1.86) and hematoma (OR = 3.40) (P < .05 for all). No difference in 5-year revision-free survival was found. The VWD patients receiving aspirin or no prescriptions had greater odds of VTE (OR = 2.39, P = .048). Those on other chemoprophylaxis agents had greater odds of hematoma (OR = 4.84, P = .006).

CONCLUSIONS

Patients with VWD undergoing THA had increased odds of 90-day VTE if using aspirin or no prescriptions, or hematoma if using other chemoprophylaxis. There is a delicate balancing act of clotting versus bleeding that must be considered in managing such patients, but it was reassuring that no difference in overall 5-year revision-free survival was found.

Cementless versus Cemented Total Knee Arthroplasty Using the Same Implant Design: A Mean 5-Year Follow-up Study

Cementless implant use continues to increase primarily due to increased numbers of younger and obese patients opting for primary total knee arthroplasty (TKA). Given the increased use of cementless implants, the purpose of this study was to evaluate the midterm clinical performance of cementless TKA using a highly porous tibial baseplate compared with its cemented counterpart of the same system. We conducted a retrospective case-control study of 400 patients undergoing primary TKA that included 200 patients with cementless components matched for age and body mass index (BMI) to 200 patients with cemented implants of the same implant design with a 5-year follow-up. We evaluated clinical results, complications, revisions, and overall survivorship between the cohorts. Statistical analysis was performed using student t-test and chi-square analysis. There was no statistical difference in age (64.3 vs. 64.3 p = 0.81), BMI (34 vs. 33.1 p = 0.19), preoperative Knee Society Score (KSS) function (41 vs. 32.3 p = 0.22), and preoperative KSS knee score (39.2 vs. 38.3 p = 0.54) between the cementless and cemented cohorts, respectively. The cementless group had seven revisions, while the cemented group had nine revisions (p = 0.609). The cementless group had one revision due to aseptic loosening versus five in the cemented group (p = 0.09). Postoperative 5-year KSS knee scores were 92.84 versus 91.75 (p = 0.386) and function scores were 81.81 versus 69.65 (p = 0.00004) in the cementless and cemented groups, respectively. The cementless group had survivorship of 96.5% for all-cause revision compared with 95.5% in the cemented group at 5-year follow-up (p = 0.60). Cementless TKA using a highly porous tibial baseplate showed excellent midterm results with one case of aseptic loosening at 5-year follow-up and with similar Knee Society outcome scores and survivorship compared with the cemented group. Cementless TKA demonstrated noninferiority to cemented TKA and could be used as an alternative mode of fixation in patients opting for primary TKA. Additional long-term follow-up is needed to determine if cementless TKA can demonstrate improved survivorship over cemented TKA.

Acute Surgical Site Complications in Direct Anterior Total Hip Arthroplasty: Impact of Local Subcutaneous Tissue Depth and Body Mass Index

Background

Body mass index (BMI) is an imperfect measure of patients' adiposity and operative risk. Radiographic and direct subcutaneous measurements have been utilized in attempts to more accurately characterize the risk of postoperative complications, including surgical site infection. This study aims to evaluate whether direct tissue depth measurement is a more accurate predictor of skin complication following direct anterior total hip arthroplasty (THA).

Methods

A retrospective chart review of patients who underwent elective THA between April 30, 2020, and January 31, 2023, was performed. Baseline demographics, antibiotics, anticoagulation, and intraoperatively measured tissue depths at proximal, middle, and distal portions of the incision were recorded. Patient follow-up was reviewed to assess the development of skin complication in the acute postoperative period.

Results

Data were collected from 280 patients who underwent THA via direct anterior approach by a single surgeon. The mean age was 66.0 years, and 52.1% were female. A total of 18/280 (6.4%) patients developed an abrasion (5/18) or superficial surgical site infection (13/18) within the first 60 days postoperatively. Patients who developed skin complications had a significantly higher BMI (33.7 kg/m2 vs 29.9 kg/m2; P = .0021). Patients with a BMI >30 kg/m2 had more than 5 times increased odds of developing a superficial skin complication in the acute 60-day postoperative period compared to those with a BMI <30 kg/m2 (Odds ratio = 5.318, P = .0059). None of the measured tissue depths, nor their average together, were shown to be significant predictors of skin complications.

Conclusions

This study showed that BMI is a significant predictor of acute skin complications in direct anterior THA patients. No other significant predictors were found to be associated with increased risk, including proximal, middle, and distal tissue depths.

Similar Efficacy and Lower Cost Associated With Ceftazidime Compared to Tobramycin Coupled With Vancomycin in Antibiotic Spacers in the Treatment of Periprosthetic Joint Infection

BACKGROUND

Vancomycin and tobramycin have traditionally been used in antibiotic spacers. In 2020, our institution replaced tobramycin with ceftazidime. We hypothesized that the use of ceftazidime/vancomycin (CV) in antibiotic spacers would not lead to an increase in treatment failure compared to tobramycin/vancomycin (TV).

METHODS

From 2014 to 2022, we identified 243 patients who underwent a stage I revision for periprosthetic joint infection. The primary outcome was a recurrent infection requiring antibiotic spacer exchange. We were adequately powered to detect a 10% difference in recurrent infection. Patients who had a prior failed stage I or two-stage revision for infection, acute kidney injury prior to surgery, or end-stage renal disease were excluded. Given no other changes to our spacer constructs, we estimated cost differences attributable to the antibiotic change. Chi-square and t-tests were used to compare the two groups. Multivariable logistic regressions were utilized for the outcomes.

RESULTS

The combination of TV was used in 127 patients; CV was used in 116 patients. Within one year of stage I, 9.8% of the TV group had a recurrence of infection versus 7.8% of the CV group (P = .60). By final follow-up, results were similar (12.6 versus 8.6%, respectively, P = .32). Adjusting for potential risk factors did not alter the results. Cost savings for ceftazidime versus tobramycin are estimated to be $68,550 per one hundred patients treated.

CONCLUSIONS

Replacing tobramycin with ceftazidime in antibiotic spacers yielded similar periprosthetic joint infection eradication success at a lower cost. While larger studies are warranted to confirm these efficacy and cost-saving results, our data justifies the continued investigation and use of ceftazidime as an alternative to tobramycin in antibiotic spacers.

Mechanical Failure of SIGMA Total Condylar-III Revision Total Knee System Modular Femoral Component Due to Bolt Screw Breakage - Our Experience in Overcoming Broken Component Incarceration

Introduction

The rising use of modular implants in revision total knee arthroplasty offers surgeons greater flexibility in addressing bone defects and achieving uniform gaps compared to monoblock counterparts. However, this enhanced functionality brings specific complications such as loosening and breakage at component coupling sites, leading to challenges due to mechanical failures and suboptimal fixation. Extracting broken components during revision surgery poses a significant challenge, prompting innovative techniques to facilitate extraction.

Case Report

We present a rare case of modular femoral component mechanical failure in a 69-year-old male, manifesting as left knee instability and acute pain while walking 4 years following revision of total knee replacement due to infection. Radiographs revealed mechanical failure of the Sigma Total Condylar-III Revision prosthesis bolt, with intra-operative extraction efforts complicated by a lodged broken bolt. Despite initial challenges, successful extraction was achieved using mosquito forceps and a universal nail extractor.

Conclusion

This case highlights the importance of documenting rare instances of mechanical failure in modular implants, emphasizing the need to understand prevalence rates and various surgical techniques for implant extraction. Our experience underscores the utility of the universal nail extractor as a valuable tool in managing difficult implant removal during revision surgery. Surgeons must remain vigilant and innovative in addressing challenges encountered during modular implant revisions.

A nurse-driven penicillin allergy risk score in the preoperative setting was associated with increased cefazolin use perioperatively

STUDY OBJECTIVE

To characterize and assess the effects of a preoperative, nurse-driven penicillin allergy risk stratification tool on rates of perioperative cefazolin and second-line antibiotic use.

DESIGN

Quasi-experimental quality improvement study of penicillin-allergic surgical patients undergoing procedures for which cefazolin is indicated.

SETTING

Outpatient Perioperative Care Clinic (PCC) for preoperative surgical patients at a tertiary care center.

PATIENTS

670 and 1371 adult penicillin-allergic PCC attendants and non-attendants, respectively.

INTERVENTION

A paper penicillin allergy risk stratification questionnaire was administered during the PCC visit. Nurses were educated on its use.

MEASUREMENTS

Antibiotic (cefazolin, clindamycin, vancomycin) use rates in the 24 months before and 17 months after intervention implementation in November 2020 (November 2018 - April 2022) were assessed in penicillin-allergic PCC attendants with statistical process control charts. Multivariable logistic regression assessed antibiotic use rates pre- and post-intervention adjusting for age, sex, surgical specialty and penicillin allergy history severity. Similar analyses were done in penicillin-allergic PCC non-attendants.

MAIN RESULTS

Of 670 penicillin-allergic PCC attendants, 451 (median [IQR] age, 66 (Sousa-Pinto et al., 2021 [14])) were analyzed pre-intervention and 219 (median [IQR] age, 66 (Mine et al., 1970 [13])) post-intervention. One month after implementation, process measures demonstrated an upward shift in cefazolin use for PCC attendants versus no shift or other special cause variation for PCC non-attendants. There were increased odds of cefazolin use (aOR 1.67, 95% CI [1.09-2.57], P = 0.019), decreased odds of clindamycin use (aOR 0.61, 95% CI [0.42-0.89], P = 0.010) and decreased odds of vancomycin use (aOR 0.56, 95% CI [0.35-0.88], P = 0.013) in PCC attendants post-intervention. This effect did not occur in PCC non-attendants. There was no increase in perioperative anaphylaxis post-intervention.

CONCLUSIONS

A simple penicillin allergy risk stratification tool implemented in the preoperative setting was associated with increased use of cefazolin and decreased rates of second-line agents post implementation.

Re: Re: Laboratory safety evaluation of bedinvetmab, a canine anti-nerve growth factor monoclonal antibody, in dogs

In their letter to the editor, Farrell et al., (2024) presented questions related to canine joint health after treatment with the anti-Nerve Growth Factor (NGF) monoclonal antibody (mAb) bedinvetmab, which was presented as a component of a non-clinical laboratory safety assessment published in Krautmann et al., (2021). Their questions appear to have stemmed from an anti-NGF mAb developed for the treatment of osteoarthritis in humans (tanezumab; FDA, 2021) which in 2021 failed to achieve marketing approval due to an unfavorable benefit: risk profile, primarily due to a syndrome called Rapidly Progressive Osteoarthritis (RPOA) which occurred more commonly in treatment groups when compared to controls. Farrell et. al. (2024) have posed questions on radiographic and histopathologic bone findings from studies included in Krautmann, et al., (2021) and communicated in the FDA's Freedom of Information summary for Librela (FDA, 2023). These findings have previously been determined to be incidental and not bedinvetmab-associated. To address the questions posed, it is important to briefly define RPOA and summarize the syndrome in humans, review why the bone/joint findings in bedinvetmab safety studies in dogs are not indicative of RPOA or an RPOA-like condition, provide an update on joint health after use of bedinvetmab since market approval (>3 years in some markets), and summarize why Zoetis, the manufacturer of Librela, has confidence in joint safety after use of bedinvetmab in dogs.

Increased prevalence of valgus constitutional alignment subtypes in a South African arthritic population group using the coronal plane alignment of the knee (CPAK) classification

BACKGROUND

Knee alignment philosophies and patient specific models to improve patient reported outcomes are gaining increasing attention. The coronal plane alignment of the knee (CPAK) classification describes nine knee phenotypes and then proposes surgical alignment strategies to achieve constitutional alignment. The CPAK classification has been validated in Australian, European, Asian and North American population groups. To date no African data has been analyzed using CPAK.

METHODS

A total of 344 arthritic patients (608 knees) with appropriate long leg radiographs were classified based on the CPAK type. Measurements included mechanical hip-knee-angle(mHKA), medial proximal tibial angle (mMPTA) and lateral distal femoral angle (mLDFA) and the derived calculations of joint line obliquity (JLO) and arithmetic hip-knee-angle (aHKA).

RESULTS

The sample population was 77.9% (n = 268) female with a mean age of 68.4 ± 9.2 years. The most common CPAK types in order were type 3 (n = 174; 28.6%), type 2 (n = 155; 25.5%), type 1 (n = 94; 15.5%) and type 6 (n = 80; 13.2%). The most common limb alignment types were valgus (CPAK types 3,6,9; 41.8%).

CONCLUSION

This study, which investigated arthritic patients from a single institution in South Africa, shows a divergence of CPAK phenotypic knee patterns relative to other international studies, with much higher proportions of valgus phenotypes (3 and 6). This regional difference should be further investigated in other South African and African population samples and used to adapt the surgical strategies employed by local surgeons.

Use of an Automated Surgical Impactor Reduces Femoral Broaching Time in Direct Anterior Approach Total Hip Arthroplasty: Results From a Randomized, Multicenter Study

Background

Impaction in total hip arthroplasty has typically been conducted using a mallet. A surgical automated impactor has been developed with the goal of reducing surgeon variability, fatigue, and injury. There is also potential to reduce the variability of each impaction step in which automated impaction is used, through reproducible and consistent application of force.

Methods

Patients were randomized into either the mallet control group, or the automated impaction study group (1:1 randomization). The primary endpoint analysis was conducted to demonstrate that femoral broaching time (in minutes) with an automated impactor is noninferior to femoral broaching time with manual instruments (mallet) under a noninferiority (NI) margin of 1.25 minutes, with a subsequent test of superiority. A total of 218 patients were randomized and treated (109 in each group).

Results

Mean femoral broaching time was 5.8 minutes in the automated impaction study group (automated), and 8.1 minutes in the mallet control group (mallet), a 28.4% reduction (P = .0005). However, there was not a difference in surgery duration between the groups. Three fractures were reported in the mallet group and 1 in the automated group.

Conclusions

In this randomized multicenter study, an automated impactor was shown to reduce femoral broaching time in primary total hip arthroplasty, with no increase in fractures, but no decrease in operating room time was noted.

Associated patellofemoral osteoarthritis is not a contraindication for unicompartmental knee replacement. Report of one hundred ten prostheses with an average 6-year follow-up

INTRODUCTION

Associated patellofemoral joint osteoarthritis (APFJ-OA) has typically been considered a contraindication for unicompartmental knee arthroplasty (UKA) in the treatment of femorotibial joint osteoarthritis. However, this contraindication is being challenged. The aim of this study was to assess clinical and functional outcomes, complications, and implant survival in medial or lateral UKA, regardless of clinical symptoms or radiographic signs of APFJ-OA.

METHODS

This retrospective, comparative study included patients treated with medial or lateral UKA regardless of preoperative symptoms or signs of APFJ-OA, with a minimum 2-year follow-up. Intraoperatively, knees were subdivided based on APFJ-OA grade, according to the Outerbridge classification. Clinical and functional outcomes were analyzed using the 2011 Knee Society Score (KSS) at the last follow-up control. APFJ-OA was treated systematically, in a tailored, stepwise fashion according to its severity. Complications and implant survival rates were evaluated. Two-sided paired T-test, ANOVA, and Kruskal-Wallis tests were used with a significance level of 5%.

RESULTS

Finally, 110 UKAs were assessed 81 (73.6%) medial and 29 (26.4%) laterals. The average follow-up was 6 years (2-19.5). According to Outerbridge, 22 knees (20%) were in grade 2, 59 (53.6%) were in grade 3, and 29 (26.4%) were in grade 4. All three groups showed a statistically significant increase in KSS scores and range of motion. There were no significant differences in clinical KSS improvement and flexion contracture between Outerbridge groups (average 35.7 and -4.9, respectively). Group 3 showed statistically significant improvement in functional KSS when compared to group 2 (68.8 vs 61.2). In maximum flexion, groups 3 and 4 did significantly better than group 2 (20° vs 15°). Three prostheses (2.7%) needed revision after 7, 8.6, and 12 years due to aseptic tibial loosening. Implant survival was 100% at 5 (64 of 64), 97% at 7 (30 of 31), 93% at 9 (14 of 15), and 89% at 12 years, respectively (8 of 9).

CONCLUSION

Clinical and functional results, complications, and survival of medial or lateral UKA were not negatively affected by APFJ-OA assessed intraoperatively using the Outerbridge classification after an average follow-up of 6 years. We consider that APFJ-OA is not a contraindication for UKA when treated systematically according to its severity.

LEVEL OF EVIDENCE

IV.