Synergistic effects of robotic surgery and IPACK nerve block on reduction of opioid consumption in total knee arthroplasty

Background

There are numerous strategies to combat postoperative analgesia and expedite recovery after total knee arthroplasty (TKA). The purpose of this study was to determine opioid consumption, length of stay, and functional outcomes after robotic versus standard TKA in the setting of various regional pain modalities.

Methods

A consecutive series of patients treated with unilateral primary robotic or standard TKA from January 2018-February 2021 were retrospectively identified. Regional pain modalities included peri-articular injection (PAI), adductor canal block (ACB), and infiltration between popliteal artery and capsule of knee (IPACK). Patient demographics, operative/perioperative variables, and postoperative function were recorded. Daily opiate consumption was calculated as morphine milligram equivalents (MME). Multivariate regression was performed to control for age, sex, and race.

Results

After review, 283 patients (177 Females; 106 Males) were included. Robotic TKA patients received IPACK + ACB (36), while standard TKA patients received either ACB (45), IPACK + ACB (167), or PAI (35). Daily inpatient opioid consumption in the standard IPACK + ACB (p = 0.02) and robotic IPACK + ACB groups (p = 0.0001) was significantly lower compared to standard ACB. When combined with IPACK block, robotic procedures synergistically lowered opiate consumption (p = 0.004) compared to standard procedures and led to earlier discharge (p = 0.003). The robotic IPACK + ACB cohort also demonstrated improved early ambulation compared to standard ACB, (p = 0.05), whereas the same benefit was not seen for patients who received IPACK during standard TKA.

Conclusions

The utilization of IPACK block decreases inpatient postoperative opioid requirements following TKA. Robotic TKA and IPACK block appeared to have a synergistic effect on opioid consumption and postoperative recovery.

A break-even analysis of tranexamic acid for prevention of periprosthetic joint infection following total hip and knee arthroplasty

Purpose

Despite the commonplace use of tranexamic acid in total joint arthroplasty, much of the current data regarding its cost-effectiveness examines savings directly related to its hemostatic properties, without considering its protective effect against periprosthetic joint infections. Using break-even economic modeling, we calculated the cost-effectiveness of routine tranexamic acid administration for infection prevention in total joint arthroplasty.

Materials and methods

The cost of intraoperative intravenous tranexamic acid, the cost of revision arthroplasty for periprosthetic joint infections, and the baseline rates of periprosthetic joint infections in patients who did not receive intraoperative tranexamic acid were obtained from the literature and institutional purchasing records. Break-even economic modeling incorporating these variables was performed to determine the absolute risk reduction in infection rate to make routine intraoperative tranexamic acid use economically justified. The number needed to treat was calculated from the absolute risk reduction.

Results

Routine use of intraoperative tranexamic acid is economically justified if it prevents at least 1 infection out of 3125 total joint arthroplasties (absolute risk reduction = 0.032%). Cost-effectiveness was maintained with varying costs of tranexamic acid, infection rates, and periprosthetic joint infection costs.

Conclusion

The routine use of intraoperative tranexamic acid is a highly cost-effective practice for infection prevention in primary and revision total joint arthroplasty. The use of tranexamic acid is warranted across a wide range of costs of tranexamic acid, initial infection rates, and costs of periprosthetic joint infection treatment.

Disturbance of osteonal bone remodeling and high tensile stresses on the lateral cortex in atypical femoral fracture after long-term treatment with Risedronate and Alfacalcidol for osteoporosis

An 83 year-old Japanese woman complained of left lateral thigh pain following a low-energy fall 4 months prior to admission. She had been treated for osteoporosis with Risedronate and Alfacalcidol for the previous five years. She was diagnosed with an atypical femoral fracture (AFF) according to the American Society for Bone and Mineral Research (ASBMR) Task Force revised criteria. Radiographs revealed cortical thickening and a transverse radiolucent fracture line in the lateral cortex of the shaft. MRI showed a high intensity signal on the T2WI image 1 cm long in the lateral cortex. The patient had normal levels of bone resorption and formation biomarkers except for low 25(OH) Vitamin D. Double fluorescent labeling was done preoperatively.

Due to significant bowing, a corrective osteotomy and intramedullary nailing were performed, and the resected bone wedge was analyzed by bone histomorphometry. Three ground sections of the lateral cortex at the fracture site showed many and large pores, with or without tetracycline labeling. Histomorphometric assessment was done on intracortical pores, classified by a novel criteria, only to assess size of the pores to know prolonged osteoclastic activity and its characteristics of inner surfaces to assess whether bone formation has been occurring or not in labeling period in remodeling cycle, and coalition of multi-pores. Increased size with widespread variation of pores suggested prolonged osteoclastic activity in the reversal/resorptive phase. Bone labeling showed lamellar bone on the endocortical surface.

We hypothesize that the case had developed from a regional disturbance of osteonal remodeling in the lateral cortex, in which accumulated microcracks might have initiated a resorption process resulting in resorption cavities, i.e., pores, which became larger due to prolonged activity of secondary osteoclasts. Various sized pores could form lamellar bone, still forming at the time of biopsy, some had formed lamellar bone, but stopped to form before labeling and not to start to form at all, probably due to incomplete coupling. Endocortical lamellar bone might had started to resorbed to smooth off endocortical surface, followed by formation of lamellar bone. The endocortical bone formation was assessed and its formation period is about 2.7 years.

A finite element analysis using preoperative CT data revealed high tensile stresses on the lateral aspect of the femur. Histomorphometric results suggest that there might be more pores in the tensile area than the compressive area. These findings may subsequently connect accumulation of microcracks, an increase of size and number of pores and coalition and subsequent fracture in the lateral cortex.

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The lateral cortex of the fracture site of atypical femoral fracture was assessed by bone histomorphometry and FEA.

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Many enlarged pores may suggest a prolonged resorptive phase, resulting in excessive resorption by secondary osteoclasts.

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There is large variation in size of pores, which is much more than that of osteons, normally observed.

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Pores were classified as types with/without label, and with/without parallel lamellae to inner surface of the pores.

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More pores in size and number were observed in the lateral cortex under tensile force than compressive force by FEA.

Prosthetic Joint Infections Due to Histoplasma capsulatum: A Report of 3 Cases

Histoplasma capsulatum causes pneumonia and multisystemic disease in humans. Musculoskeletal involvement in histoplasmosis is most often tenosynovitis and rarely septic arthritis. Even more uncommon is the involvement of prosthetic joints. Here, we report a series of 3 cases of prosthetic joint failures caused by infection due to H capsulatum. Together with a review of 4 previously reported cases, we summarize host characteristics, clinical presentation, surgical approaches, antifungal management, and outcomes of this rare orthopedic joint infection.

The Impact of State Level Public Policy, Prescriber Education, and Patient Factors on Opioid Prescribing in Elective Orthopedic Surgery: Findings From a Tertiary, Academic Setting

Background

The United States is in the midst of an opioid misuse epidemic. There have been recent changes to North Carolina’s public policy leading to institutional education attempting to reduce high-risk opioid prescribing. This study investigated whether state-level and institutional efforts were associated with provider-level changes in opioid prescriptions after common orthopedic surgeries.

Patients and Methods

Six-week post-operative opioid prescribing in patients 18 years or older undergoing high-volume elective surgeries were reviewed retrospectively. Three patient cohorts from equivalent calendar year periods were included in this analysis; preceding policy implementation (January 1, 2017, to March 31, 2017), immediately after policy implementation (January 1, 2018, to March 31, 2018), and 1 year after policy implementation (January 1, 2019, to March 31, 2019). Multivariable models were constructed to evaluate the effects of public policy and institutional education on postoperative opioid prescribing.

Results

The mean (standard deviation) amount of oxycodone 5-mg equivalents prescribed at discharge decreased from 75.6 (53.2) in 2017 to 55.7 (36.2) in 2018 and then 45.6 (32.6) in 2019 (P < .05). Similarly, 6-week postoperative cumulative oxycodone 5-mg equivalents prescribed also significantly decreased from 123.3 (145.8) in 2017 to 84.1 (90.3) in 2018 and to 80.2 (150.1) in 2019. Other outcomes including prescription duration and rates of outlier prescribing showed similar trends.

Conclusion

In a North Carolina tertiary academic hospital, opioid prescribing decreased after public policy implementation and an institutional response of education for prescribers within a national context of changing practices in opioid prescribing. State-level public policy and prescriber education could be important avenues for decreasing postoperative opioid prescription in orthopedic settings.

Impact of body mass index on hemoglobin level and blood transfusion in total knee arthroplasty: A retrospective case control study

Background

Morbid obesity is a challenge in cases that require total knee arthroplasty, and several studies considered it a contraindication for the procedure due to associated risk of complications, including plummeting hemoglobin levels and subsequent need for a blood transfusion. This study investigated risk factors for blood transfusion in this patient group and considered their relationship to obesity.

Materials and methods

Patients' data were extracted from medical records, including estimated blood loss and perioperative hemoglobin levels. Patients were weighed and measured, and their body mass index (BMI) was calculated and stratified according to international criteria.

Results

A total of 188 patients were included in this study; among them, 136 patients had obesity (72%), with a mean BMI of 33.54. The mean volume of blood lost was 1055.4 ml, with the mean postoperative hemoglobin decrease of 1.42 g/dl and 2.88 g/dl at 6 and 24 h after surgery, respectively. The pre-operative Hb level was the only significant risk factor for blood transfusion. BMI did not affect the risk of blood transfusion or amount of blood lost.

Conclusion

Obesity (BMI > 30 kg/m²) did not increase the risk of needing a blood transfusion after total knee arthroplasty. A judicious transfusion strategy involving the pre-operative Hb optimization should be adopted in TKA to decrease transfusion rate, benefit patient outcomes, and increase healthcare system efficiency. This study shows that high BMI is not a risk factor for postoperative blood transfusion.

Benefit of subcutaneous patient controlled analgesia after total knee arthroplasty

Purpose

Subcutaneous patient-controlled analgesia (PCA) has been widely used for orthopedic surgeries including total knee arthroplasty (TKA). This study aims to clarify the usefulness of subcutaneous PCA in the early phase after TKA.

Methods

Our subjects consisted of 88 osteoarthritis knee patients who underwent primary TKA, and were classified into two groups: 42 patients received a subcutaneous PCA (containing fentanyl and droleptan) after operation (PCA group), and 46 patients were managed without a subcutaneous PCA (control group). We compared the incidence of side effects for 3 days postoperatively, measuring the number of times patients used adjuvant analgesia and range of motion on day 7 between the two groups. 34 of 42 patients in the PCA group tolerated PCA use until POD 3 (continuation sub-group), while 8 patients could not continue PCA (interruption sub-group). Demographic data of the two sub-groups were compared.

Results

The mean number of times adjunctive analgesics were used by the PCA group (3.7 ± 2.2) was significantly less than in the control group (5.4 ± 2.8) (p = 0.0049). There were no significant differences in the frequency of side effects between the two groups. There was no significant difference in range of motion between the two groups. Comparing the continuation and interruption sub-groups, patients over 80 years old were at risk to discontinue a subcutaneous PCA (p = 0.0319, odds ratio 5.4).

Conclusion

These findings demonstrate that subcutaneous PCA would be a safe postoperative pain regimen for TKA patients, but the effect was not enough to promote early functional recovery.

Levels of evidence

Therapeutic, Level Ⅱ.

The Effect of Body Mass Index on Functional Outcome of Patients With Knee Replacement

Objective

To investigate the effects of body mass index (BMI) on the rehabilitation process in patients with a recent knee replacement.

Design

This retrospective cohort study included all patients admitted to a rehabilitation hospital, with a recent diagnosis of knee replacement and available hospital admission data including height and weight, between 2014 and 2017.

Setting

Rehabilitation hospital.

Participants

Study participants included patients who had undergone knee replacement surgery (N=742), with available BMI data.

Interventions

None.

Main Outcome Measures

FIM scores, including FIM change per day (FIM efficiency) by BMI category.

Results

The chart review identified 742 patients who had undergone knee replacement surgery, with available BMI data. The identified patients ranged in age from 58 to 85 years, with a mean age of 70 years. Of the patients included in the study, 24 were male, 49 were female, 73 were within the normal weight class, 180 in the overweight class, 189 in the obese class I, 143 in the obese class II, and 157 patients were classified as obese class III. The mean FIM efficiency was highest in the obese class II category (3.96). In a multivariate analysis after controlling for age, obese classes II and III had significantly better FIM efficiency.

Conclusion

This study did not demonstrate that obesity adversely affects the rate of recovery during hospitalization after knee replacement surgery.

Use of porous monoblock patella component should avoid for patient with patella baja

Background

Although many studies have evaluated the success of porous tantalum component in primary and revision cementless total knee arthroplasty (TKA) cases, few studies have reported the breakage of porous tantalum monoblock patella component (PTMP). The purpose of this study was to investigate the radiographic outcomes of breakage of PTMP at short-term follow up.

Methods

This was a retrospective study of 49 consecutive knees in 43 patients who underwent TKA surgery between September 2012 and March 2014. Bone marrow contents/tissue volumes (BMC/TV. mg/cm³) were evaluated using 2-dimensional osteomorphometry software with 2D- multi-detector-row computed tomography (2D-MDCT) to measure fixation of the bone-prosthesis interface with patella at 6, 12, and 24 months after surgery. Clinical follow up was obtained by reviewing each patient at orthopedic record.

Results

We experienced a case that resulted in breakage of PTMP without traumatic episode at 26 months after surgery. Relative changes of Bone Mineral Contents per Tissue Volume. (BMC/TV mg/cm³) at ROI. 1 (superior border of the patella) and ROI. 2 (peg of patella) were significantly higher than ROI.3 (inferior border of patella) at 6, 12 and 24 months after surgery (p < 0.001. p < 0.01). Patient with breakage of PTMP has patella baja (Insall- Salvati ratio: 0.72), and the relative change of BMC/TV at ROI.1 and 2 for patients who experienced a breakage of PTMP was higher than any other patients.

Conclusion

The present study revealed that the use of PTMP should be avoided for patients with patella baja.