Oxidized Zirconium Versus Cobalt Chromium for Primary TKA: No Difference in Midterm Revision Rates From the American Joint Replacement Registry.

BACKGROUND: Cobalt chromium (CoCr) is the most commonly used material in TKA; however, the use of oxidized zirconium (OxZr) implants has increased. The advantages to this material demonstrated in basic science studies have not been borne out in clinical studies to date. QUESTION/PURPOSE: In the setting of the American Joint Replacement Registry (AJRR), how do revision rates differ between CoCr and OxZr after primary TKA? METHODS: The AJRR was accessed for all primary TKAs performed between 2012 and 2020 for osteoarthritis, resulting in 441,605 procedures (68,506 with OxZr and 373,099 with CoCr). The AJRR is the largest joint replacement registry worldwide and collects procedure-specific details, making it ideal for large-scale comparisons of implant materials in the United States. Competing risk survival analyses were used to evaluate the all-cause revision rates of primary TKAs, comparing CoCr and OxZr implants. Data from the Centers for Medicare and Medicaid Services claims from 2012 to 2017 were also cross-referenced to capture additional revisions from other institutions. Revision rates were tabulated and subclassified by indication. Multivariate Cox regression was used to account for confounding variables such as age, gender, region, and hospital size. RESULTS: After controlling for confounding variables, there were no differences between the OxZr and CoCr groups in terms of the rate of all-cause revision at a mean follow-up of 46 ± 23 months and 44 ± 24 months for CoCr and OxZr implants, respectively (hazard ratio 1.055 [95% confidence interval 0.979 to 1.137]; p = 0.16) The univariate analysis demonstrated increased rates of revisions for pain and instability in the OxZr group (p = 0.003 and p < 0.001, respectively). CONCLUSION: These findings suggest there is no difference in all-cause revision between OxZr and CoCr implants in the short-term to mid-term. However, further long-term in vivo studies are needed to monitor the safety and all-cause revision rate of OxZr implants compared with those of CoCr implants. OxZr implants may be favorable in patients who have sensitivity to metal. Despite similar short-term to mid-term all-cause revision rates to CoCr implants, because of the limitations of this study, definitive recommendations for or against the use of OxZr cannot be made. LEVEL OF EVIDENCE: Level III, therapeutic study.

Comparison of Femoral Nerve Catheter, Adductor Canal Catheter, and Periarticular Liposomal Bupivacaine Infiltration for Postoperative Analgesia After Primary Total Knee Arthroplasty.

BACKGROUND: Peripheral nerve catheters are used to provide analgesia after total knee arthroplasty (TKA) and have been shown to decrease pain and opioid use, to facilitate participation with physical therapy (PT), and to hasten discharge. More recently, pericapsular infiltration using liposomal bupivacaine (LB) has been employed as an alternative analgesic approach. METHODS: This retrospective study compared outcomes for three analgesic approaches: femoral nerve catheter (FNC), adductor canal catheter (ACC), and intraoperative LB infiltration. The primary outcome was numeric rating scale (NRS) pain scores at 24 hours. Secondary outcomes included pain scores at 12, 36, and 48 hours, time-to-first opioid, cumulative opioid use, distance walked, and time-to-discharge. RESULTS: Pain scores at 24 hours were significantly lower in both the ACC and FNC cohorts when compared to the LB cohort (3.1 versus 4.6 [P = .017] and 2.4 versus 4.6 [P < .0001]). The ACC and FNC groups did not differ significantly at that timepoint (P = .27). Similar comparisons were found at 12 and 36 hours, while at 48 hours the FNC group was superior. Time to first opioid and opioid consumption favored the ACC and FNC groups. Walking distance favored the ACC group. Both the ACC and LB groups had a faster time-to-discharge than the FNC group. CONCLUSION: Both ACCs and FNCs provided superior analgesia at 24 hours compared to LB, while being equivalent to each other. Pain scores at 12 hours and 36 hours as well as opioid consumption through 48 hours mirrored this finding. Although various differences were found between groups in terms of time-to-first analgesic, walking distance and time-to-discharge, the ACC approach appeared to optimally balance analgesia, ambulation, and time-to-discharge.

Characterizing Particle Evacuation in the Setting of Positive-pressure Body Exhaust Suit Using a Novel Gloving Technique.

The sterility of the gown-glove interface during total joint arthroplasty is a key factor in preventing contamination of the surgical field. To compare the potential of gown-glove interface contamination with a novel gloving technique versus standard gloving technique. We performed a study quantifying potential gown-glove interface contamination using two different gloving techniques. A 5 µm fluorescent powder simulated potential bacterial contamination. Each group gowned and gloved each hand using a modified technique versus traditional technique. Ultraviolet light was used to measure contamination at the gown-glove interface after performing a simulated surgery. The modified gloving technique did not statistically reduce the contamination at the gown-glove interface compared to the traditional gloving technique (p = 0.27). Despite using a gloving technique recently described as decreasing contamination, we noted contamination at the interface after performing a simulated surgery with a positive pressure exhaust suit. Further study is needed. (Journal of Surgical Orthopaedic Advances 30(3):166-169, 2021).

Dilute Povidone-Iodine Solution Prevents Intraoperative Contamination of Sterile Water Basins During Total Joint Arthroplasty.

BACKGROUND: Periprosthetic joint infection is a major complication of total joint arthroplasty (TJA). The intraoperative splash basin has been found to be a potential source of contamination. Although consensus recommendations against the use of splash basin have been made, splash basin use continues to be taught and utilized in practice. This study aims to investigate the effect of dilute betadine addition to the sterile water (SW) contents (0.02% solution) of the splash basin on contamination rates. This intervention could preserve the functionality and preferential use of the splash basin. The primary outcome of this study is the rate of splash basin contamination, with secondary outcomes of prevalence of culture speciation and mean operative times association with the rate of positive cultures. METHODS: Patients undergoing primary TJA were enrolled in a randomized controlled trial with assignment to either the intervention/betadine group, in which dilute betadine was added to the standard SW splash basin, or the control/standard SW group. For a total cohort of 104 patients, a 120 mL aliquot sample of basin fluid was collected at incision ("preprocedure") and closure ("postprocedure"). Samples were cultured and monitored for 48 hours for growth, with further testing as necessary to identify microbial speciation. RESULTS: Of the final 100 postprocedure samples, 0 (0.0%) were positive in the betadine group, while there were 23 (47.9%) positive samples in the SW group (P < .001). Of the positive cultures, the most common species grown were coagulase-negative Staphylococcus, Corynebacterium, and Micrococcus. The mean operative time was an average of 11 minutes longer for cases with positive cultures. CONCLUSION: In conclusion, treating SW splash basins with dilute povidone-iodine (0.02% solution) eliminates intraoperative contamination of splash basins in TJA procedures. This intervention is simple, low cost, and readily implementable, making it a reasonable addition to TJA protocols. LEVEL OF EVIDENCE: Level 1, Controlled Laboratory Study.

Noise Exposure and Risk of Noise Induced Hearing Loss to the Adult Reconstruction Surgeon: Recommendations for Prevention and Monitoring.

Goal of the study was to determine the average noise exposure to the orthopaedic surgeon performing hip and knee arthroplasty and the benefit of customized hearing protection. Data from dosimeters (3MTM Edge 4) worn by three adult reconstruction orthopedic surgeons for a total of 27 operative day recordings was analyzed using 3MTM Detection Management Software (product version 2.7.152.0). Westone TRU custom hearing protection was used with different filters according to noise reduction rating (NRR). The overall average decibel level was 80.64 dB (73.6-87.2 dB, +/- 4.18). The peak decibel level averaged 103.66 dB (97.30-110.30, +/-3.02). The authors subjective trial of custom hearing protection determined the NRR 10 and 15 filters were most effective at noise reduction with adequate ability to communicate effectively. Our study demonstrates that the daily exposure to the total joint surgeon exceeds safe levels. (Journal of Surgical Orthopaedic Advances 29(4):202-204, 2020).

An Update to a Novel Technique for Centering the Femoral Stem in Primary Total Hip Arthroplasty.

Careful surgical technique is a critical component of total hip arthroplasty. Femoral preparation and component positioning are vital to improving outcomes and preventing complications. Femoral preparation begins with creating an entry hole in the proximal femur. Various tools have been used for this purpose which resemble a "cookie cutter." An axial starter reamer, or awl, is then inserted through the entry hole in the proximal femur to aid in opening and centralizing the canal for sequential reaming or broaching. A novel technique was described previously which allows the awl to center itself in the canal with little risk of deviation from midline or cortical perforation. Since describing this technique in 2014, the senior surgeon has further modified the method of preparing the entry hole in the proximal femur. The surgeon now uses a 1/8" drill bit to penetrate the piriformis fossa, instead of a "cookie cutter" or osteotome. A 1/8" entry hole eliminates gaps between the bone and the implant, results in lateralization of the stem, and avoids varus malposition. We evaluated 300 primary hip arthroplasties by a single surgeon using one of the three techniques: traditional clockwise technique (Group 1), our previously published novel counterclockwise technique (Group 2), and our updated novel technique (Group 3). While the deviation from midline of Group 3 did not differ significantly from Group 2, it was significantly less than the deviation from midline of Group 1 (p=00006). This simple updated technique enables the surgeon to avoid potential malalignment during femoral preparation.

A Bundle Protocol to Reduce the Incidence of Periprosthetic Joint Infections After Total Joint Arthroplasty: A Single-Center Experience.

BACKGROUND: Periprosthetic joint infection (PJI) represents a devastating complication of total hip arthroplasty (THA) or total knee arthroplasty (TKA). Modifiable patient risk factors as well as various intraoperative and postoperative variables have been associated with risk of PJI. In 2011, our institution formulated a "bundle" to optimize patient outcomes after THA and TKA. The purpose of this report is to describe the "bundle" protocol we implemented for primary THA and TKA patients and to analyze its impact on rates of PJI and readmission. METHODS: Our bundle protocol for primary THA and TKA patients is conceptually organized about 3 chronological periods of patient care: preoperative, intraoperative, and postoperative. The institutional total joint database and electronic medical record were reviewed to identify all primary THAs and TKAs performed in the 2 years before and following implementation of the bundle. Rates of PJI and readmission were then calculated. RESULTS: Thirteen of 908 (1.43%) TKAs performed before the bundle became infected compared to only 1 of 890 (0.11%) TKAs performed after bundle implementation (P = .0016). Ten of 641 (1.56%) THAs performed before the bundle became infected, which was not statistically different from the 4 of 675 (0.59%) THAs performed after the bundle that became infected (P = .09). CONCLUSION: The bundle protocol we describe significantly reduced PJIs at our institution, which we attribute to patient selection, optimization of modifiable risk factors, and our perioperative protocol. We believe the bundle concept represents a systematic way to improve patient outcomes and increase value in total joint arthroplasty.

Cost Analysis of Sending Routine Pathology Specimens following Total Joint Arthroplasty in the Age of Bundled Payments.

Bundled payment plans are being developed as a means to curb healthcare spending. Routine histology following total hip arthroplasties (THA) and total knee arthroplasties (TKA) is standard practice at many institutions. Recently, the value of this practice has been questioned as histologic diagnoses in THA and TKA rarely differ from the clinical diagnoses. The goal of this study is to identify discrepant and discordant diagnoses following THA and TKA at an academic medical center and to calculate the cost-saving potential in the setting of a bundled payment plan. A retrospective chart review was conducted on 1,213 primary THA and TKA performed by two orthopaedic surgeons from 2012 to 2014. The clinical and histologic diagnoses were compared and classified as concordant, discrepant, or discordant. Cost information was obtained from the institutional billing office. One thousand one hundred and sixty-six THA and TKA were analyzed in the final cohort. Nineteen (1.6%) diagnoses were classified as discrepant while none were discordant. The cost of histologic examination per specimen was estimated to be $48.56. The total cost of all arthroplasties was $14,999,512.46, of which histologic examination made up 0.31% of the total cost. The results of this study corroborate the results of previous studies and support the proposition that routine histologic examination is not cost-effective. The cost incurred to perform histologic examination will become a cost deduction from future bundled payments. The practice of sending routine histologic specimens following TJA should be decided upon by the operating orthopaedic surgeon.

Retained Gastric Contents After Adequate Fasting Associated with GLP-1 Receptor Agonist Use: A Report of 3 Cases.

CASES: Three patients presented for orthopaedic surgery on glucagon-like peptide receptor agonist (GLP-1 RA) medications with a minimum fasting time of 10 hours. Gastric ultrasound confirmed the presence of retained solids in the stomach; all 3 cases were postponed. CONCLUSION: There is growing concern for increased perioperative aspiration risk related to delayed gastric emptying associated with GLP-1 RA and a paucity of literature to guide perioperative management. This may cause case cancellation over safety concerns for elective procedures. The presented cases illustrate the association of GLP-1 RA drugs and delayed gastric emptying causing case postponement.

Randomized controlled trial of intrathecal oxytocin on speed of recovery after hip arthroplasty.

ABSTRACT: Recovery from surgery is quicker in the postpartum period, and this may reflect oxytocin action in the spinal cord. We hypothesized that intrathecal injection of oxytocin would speed recovery from pain and disability after major surgery. Ninety-eight individuals undergoing elective total hip arthroplasty were randomized to receive either intrathecal oxytocin (100 µg) or saline. Participants completed diaries assessing pain and opioid use daily and disability weekly, and they wore an accelerometer beginning 2 weeks before surgery until 8 weeks after. Groups were compared using modelled, adjusted trajectories of these measures. The study was stopped early due to the lack of funding. Ninety patients received intrathecal oxytocin (n = 44) or saline (n = 46) and were included in the analysis. There were no study drug-related adverse effects. Modelled pain trajectory, the primary analysis, did not differ between the groups, either in pain on day of hospital discharge (intercept: -0.1 [95% CI: -0.8 to 0.6], P = 0.746) or in reductions over time (slope: 0.1 pain units per log of time [95% CI: 0-0.2], P = 0.057). In planned secondary analyses, postoperative opioid use ended earlier in the oxytocin group and oxytocin-treated patients walked nearly 1000 more steps daily at 8 weeks ( P < 0.001) and exhibited a clinically meaningful reduction in disability for the first 21 postoperative days ( P = 0.007) compared with saline placebo. Intrathecal oxytocin before hip replacement surgery does not speed recovery from worst daily pain. Secondary analyses suggest that further study of intrathecal oxytocin to speed functional recovery without worsening pain after surgery is warranted.

Closing Time: One Last Call for Patient Preference.

Background: Wound closure method in total hip and knee arthroplasty is a controversial topic with no differences in clinical outcomes between surgical staples (SS) and subcutaneous sutures with Dermabond (SCD). When clinically appropriate, providers should focus more on what the patient may prefer. This study aimed to collect data on patient preference between SS and SCD and analyze differences in preference based on gender and previous surgical histories. Methods: Patients were surveyed on their wound closure preferences prior to surgery. The handout given collected preference and patient demographics. Risk ratios and risk difference with 95% confidence intervals (95% CI) were calculated along with Firth-corrected logistic regressions. Results: A total of 163 participants were analyzed (53% female) (average age = 63.8 years), in which 12 participants selected SS as their preferred method. Males demonstrated no difference in relative risk (risk ratio: 2.3 [95% CI: 0.7, 7.3], P = .150) or absolute risk (risk difference: 5.9 [-2.2, 14.1], P = .156) in choosing SS over SCD. Patients that previously sustained SS for other surgeries demonstrated no difference in adjusted odds (adjusted: 0.9 [95% CI: 0.2, 3.2], P = .839) in choosing SS over SCD. Conclusion: More patients favored SCD over SS. There was no difference in preferences based on gender or previous surgical history. Current literature shows that successful wound closure is achieved with minimized risks for infection and other complications using both methods. Providers should adopt a patient-centric approach and perform the closure method that most patients prefer when medically warranted.

Does a plastic drape reduce incidence of heterotopic ossification after hip resurfacing?

BACKGROUND: High rates of heterotopic ossification have been associated with hip resurfacing as compared to THA. Bone debris from femoral head reamings is cited as one of the risk factors linked to increased rates of heterotopic ossification. QUESTIONS/PURPOSES: We therefore asked whether (1) the incidence of heterotopic ossification differed with and without the use of a plastic drape used to collect bone debris and (2) any of a number of variables (age, gender, diagnosis, previous hip surgery, operative time, and blood loss) related to the occurrence of HO. METHODS: We retrospectively reviewed 136 hip resurfacings performed using one of two techniques: Group 1 contained 64 hip resurfacings performed using a sterile drape around the femoral neck while reaming the femoral head to collect bone debris; Group 2 contained 72 hip resurfacings carried out with manually removing bone debris and utilizing a pulse lavage. Data were collected with respect to diagnosis, gender, previous surgery, postoperative complications, operative time, and blood loss to rule out confounding variables. The amount of heterotopic ossification was measured radiographically in hips after undergoing resurfacing arthroplasty. The minimum followup was 6 months (mean, 15 months; range, 6-27 months). RESULTS: No patient had heterotopic ossification of clinical importance and none had resection of the heterotopic ossification. Group 1 had a lower overall incidence of minor heterotopic ossification (32%) than Group 2 (58%). Risk factors linked to heterotopic ossification include male gender and operative time. CONCLUSIONS: The use of a plastic drape to collect bone debris from femoral head reamings decreased the incidence of heterotopic ossification in resurfacing arthroplasty of the hip.

Use of intraoperative computed tomography scanning in determining the magnitude of arthroscopic osteochondroplasty.

Femoroacetabular impingement has recently become a recognized cause of disability and hip arthritis. Hip arthroscopy and femoroacetabular reshaping have been performed to treat this condition. Quantification of the excess femoral and acetabular bone requiring resection has been challenging with the less invasive arthroscopic technique. We describe the use of intraoperative computed tomography assessing osteochondroplasty during arthroscopic surgery to treat cam- and pincer-type femoroacetabular impingement. We also describe the technical steps and present the important radiologic findings we have been able to visualize. We found intraoperative computed tomography scanning to be a reliable and reproducible method of assessing the quality of femoroacetabular impingement surgery. We believe that femoroacetabular impingement surgery can be assessed intraoperatively by use of computed tomography scanning where corrections can be made if necessary.

The Clinical Application of Augmented Reality in Orthopaedics: Where Do We Stand?

PURPOSE OF REVIEW: The surgical community is constantly working to improve accuracy and reproducibility in patient care, with the goal to improve patient outcomes and efficiency. One area of growing interest with potential to meet these goals is in the use of augmented reality (AR) in surgery. There is still a paucity of published research on the clinical benefits of AR over traditional techniques, but this article aims to present an update on the current state of AR within orthopaedics over the past 5 years. RECENT FINDINGS: AR systems are being developed and studied for use in all areas of orthopaedics. Most recently published research has focused on the areas of fracture care, adult reconstruction, orthopaedic oncology, spine, and resident education. These studies have shown some promising results, particularly in surgical accuracy, decreased surgical time, and less radiation exposure. However, the majority of recently published research is still in the pre-clinical setting, with very few studies using living patients. AR supplementation in orthopaedic surgery has shown promising results in pre-clinical settings, with improvements in surgical accuracy and reproducibility, decreased operating times, and less radiation exposure. Most AR systems, however, are still not approved for clinical use. Further research is needed to validate the benefits of AR use in orthopaedic surgery before it is widely adopted into practice.

Removing Well-Fixed, Collared and Noncollared Tapered Hip Stems Without an Extended Trochanteric Osteotomy Using a Novel Stem Removal System.

Improvements in materials, components, and surgical techniques in cementless total hip arthroplasty are resulting in improved femoral stem fixation through bony ongrowth or ingrowth. While improved femoral stem fixation is one reason for the current excellent total hip survivorship, indications for stem removal such as infection, implant fracture, or osteolysis remain. A commonly used technique for fully ingrown femoral stems is an extended trochanteric osteotomy which can result in comminuted fractures of the proximal femur during stem removal requiring additional fixation. Therefore, a novel hip stem removal was developed to facilitate removal of these well-ingrown stems without the need for an extended trochanteric osteotomy. This study describes the removal system and surgical technique and presents a case series of successfully removed ingrown stems.

Quantifying the force transmission through the pelvic joints during total hip arthroplasty: A pilot cadaveric study.

BACKGROUND: Total hip arthroplasty is one of the most successful and cost effective procedures in orthopedics. The purpose of this study is to investigate force transmission through the sacroiliac joint as a possible source of post-operative pain after total hip arthroplasty through the following three questions: Does the ipsilateral sacroiliac joint, contralateral sacroiliac joint, or pubic symphysis experience more force during placement? Does the larger mallet used to seat the implant generate a higher force? Does the specimen's bone density or BMI alter force transmission? METHODS: A solid design acetabular component was impacted into five human cadaver pelves with intact soft tissues. The pressure at both sacroiliac joints and the pubic symphysis was measured during cup placement. This same procedure was replicated using an existing pelvis finite element model to use for comparison. FINDINGS: The location of the peak force for each hammer strike was found to be specimen specific. The finite model results indicated the ipsilateral sacroiliac joint had the highest pressure and strain followed by the pubic symphysis over the course of the full simulation. The heft of the mallet and bone mineral density did not predict force values or locations. The largest median force was generated in extremely obese specimens. INTERPRETATION: Contrary to previous ideas, it is highly unlikely that forces experienced at the pelvic joints are large enough to contribute post-operative pain during impaction of an acetabular component. These results indicate more force is conveyed to the pubic symphysis compared to the sacroiliac joints.

Utility of Radiographs, Computed Tomography, and Three Dimensional Computed Tomography Pelvis Reconstruction for Identification of Acetabular Defects in Residency Training.

PURPOSE: The Paprosky classification system of acetabular defects is complex and its reliability has been questioned. The purpose of this study was to evaluate the effectiveness of different radiologic imaging modalities in classifying acetabular defects in revision total hip arthroplasty (THA) and their value of at different levels of training. MATERIALS AND METHODS: Bone defects in 8 revision THAs were classified by 2 fellowship-trained adult reconstruction surgeons. A timed presentation with representative images for each case (X-ray, two-dimensional computed tomography [CT] and three-dimensional [3D] reconstructions) was shown to 35 residents from the first postgraduate year of training year of training (PGY-1 to PGY-5), 2 adult reconstruction fellows and 2 attending orthopaedic surgeons. The Paprosky classification of bone defects was recorded. The influence of image modality and level of training on classification were analyzed using chi-square analysis (alpha=0.05). RESULTS: Overall correct classification was 30%. The level of training had no influence on correct classification (P=0.531). Using X-ray led to 37% correctly identified defects, CT scans to 33% and 3D reconstructions to 20% of correct answers (P<0.001). There was no difference in correct classification based defect type (P<0.001). Regardless of level of training or imaging, 64% of observers recognized type 1 defects, compared to only 16% correct recognition of type 3B defects. CONCLUSION: Using plain X-rays led to an increased number of correct classification, while regular CT scan and 3D CT reconstructions did not improve accuracy. The classification system of acetabular defects can be used for treatment decisions; however, advanced imaging may not improve its utilization.

A novel technique for centering the femoral stem in primary total hip arthroplasty.

Careful surgical technique is a critical component of total hip arthroplasty. Femoral preparation and component positioning are vital to improving outcomes and preventing complications. Using the starting awl when preparing the femur aids in opening and centralizing the canal for sequential reaming or broaching. Although traditional techniques can lead to a deviation from midline, a novel technique allows the awl to center itself in the canal with little risk for cortical perforation. We evaluated 200 patients whose surgeries were performed by a single surgeon using the traditional technique (group 1) or a novel technique (group 2) and found a statistically significant difference in mean deviation from midline. In group 2, the mean deviation was 0.34°; in group 1, the mean deviation was 0.85°. Our novel technique provides a safe, easily reproducible approach to using the starter awl in femoral preparation.