Validation of a Novel Software Measurement Tool for Total Hip Arthroplasty

Background

Preoperative planning and postoperative evaluation of component position in total hip arthroplasty (THA) utilize specialized software that must be able to provide measurements that are both accurate and precise. A new software program for use in THA has recently been developed. We sought to evaluate the accuracy of this new software in comparison with two current, widely used software programs.

Methodology

Postoperative anteroposterior (AP) pelvic radiographs from 135 THA patients were retrospectively reviewed. Reference values for acetabular anteversion, inclination, and leg length were established using validated software programs (TraumaCad^® as the primary reference value [PRV] and OsiriX Lite^TM as the secondary reference value [SRV]). Measurements from the new software program (Intellijoint VIEW^TM) were compared with reference values using Student’s t-test and chi-square test.

Results

For anteversion, mean values for the PRV (27.34° ± 7.27°) and the new software (27.29° ± 7.21°) were not significantly different (p = 0.49). The new software differed from the PRV by a mean of 0.05° ± 0.93°. Similar results were noted for inclination, where the new software differed from the PRV and SRV by -0.13° ± 0.65° and 0.25° ± 1.26°, respectively (mean values: PRV: 43.62° ± 6.02°; SRV: 43.99° ± 6.27°; new software: 43.74° ± 6.17°; p = 0.87), and for leg length, where the new software differed from the PRV and SRV by 0.05 mm ± 0.46 mm and 0.22 mm ± 0.52 mm, respectively (mean values: PRV: 10.61 mm ± 11.60 mm; SRV: 10.77 mm ± 11.70 mm; new software: 10.56 mm ­ ± 11.61 mm; p = 0.98). Measurements were highly correlated across multiple reviewers (intraclass correlation coefficient ≥0.987).

Conclusions

The new software measurement tool is accurate and precise for assessing the acetabular component position and leg length measurements following THA in AP pelvic radiographs compared to currently used image measurement software.

Total femur replacement in a patient with chronic persistence osteomyelitis - A case report

INTRODUCTION AND IMPORTANCE

Total femoral replacement (TFR) is a salvage surgical procedure that has been indicated mainly for oncologic indication to avoid lower limb amputation but has recently been indicated for non-oncological disorders.

CASE PRESENTATION

We report the case of a 63-year-old male with chronic osteomyelitis of the left femur, severe pain and bone deformation, the risk of amputation in this patient was very high. The patient underwent total femur replacement (TFR) with a modular mega-prosthesis. TFR was conducted in two phases. The first one consists of femur resection followed by placement of antibiotic cement; and the second operation was performed after 7 weeks, in which a modular mega-prosthesis was implanted. After a 2-month rehabilitation period, the patient recovered basic ambulation without any complaint of pain or detectable residual infection. The 1-year follow-up was uneventful, with no residual pain or infection. The patient retains normal ambulation and daily function.

CLINICAL DISCUSSION

Chronic persistent osteomyelitis is a hard to manage non-neoplastic disorder that leads to amputation in severe cases. In such patients, TFR would be considered as a salvage therapy that could preserve the patient's anatomical integrity and ambulation.

CONCLUSION

To the best of our knowledge, this is the first case of TFR for treatment of chronic persistent osteomyelitis in Vietnam. While TFR are still mainly indicated for oncology patients, TFR is anticipated to be performed more frequently for non-oncological disorders where there are extensive femoral bone loss and risk of amputation.

Spontaneous HIT syndrome: Knee replacement, infection, and parallels with vaccine-induced immune thrombotic thrombocytopenia

Heparin-induced thrombocytopenia (HIT) is characterized clinically by thrombocytopenia, hypercoagulability, and increased thrombosis risk, and serologically by platelet-activating anti-platelet factor 4 (PF4)/heparin antibodies. Heparin-"induced" acknowledges that HIT is usually triggered by a proximate immunizing exposure to heparin. However, certain non-heparin medications (pentosan polysulfate, hypersulfated chondroitin sulfate, fondaparinux) can trigger "HIT". Further, naturally-occurring polyanions (bacterial lipopolysaccharide, DNA/RNA) can interact with PF4 to recapitulate HIT antigens. Indeed, immunologic presensitization to naturally-occurring polyanions could explain why HIT more closely resembles a secondary, rather than a primary, immune response. In 2008 it was first reported that a HIT-mimicking disorder can occur without any preceding exposure to heparin or polyanionic medications. Termed "spontaneous HIT syndrome", two subtypes are recognized: (a) surgical (post-orthopedic, especially post-total knee arthroplasty, and (b) medical (usually post-infectious). Recently, COVID-19 adenoviral vector vaccination has been associated with a thrombotic thrombocytopenic disorder associated with positive PF4-dependent enzyme-immunoassays and serum-induced platelet activation that is maximal when PF4 is added. Vaccine-induced immune thrombotic thrombocytopenia (VITT) features unusual thromboses (cerebral venous thrombosis, splanchnic vein thrombosis) similar to those seen in spontaneous HIT syndrome. The emerging concept is that classic HIT reflects platelet-activating anti-PF4/heparin antibodies whereas spontaneous HIT syndrome and other atypical "autoimmune HIT" presentations (delayed-onset HIT, persisting HIT, heparin "flush" HIT) reflect heparin-independent platelet-activating anti-PF4 antibodies-although the precise relationships between PF4 epitope targets and the clinical syndromes remain to be determined. Treatment of spontaneous HIT syndrome includes non-heparin anticoagulation (direct oral Xa inhibitors favored over direct thrombin inhibitors) and high-dose immunoglobulin.

Trunnion Failure in Revision Total Knee Arthroplasty

In revision total knee arthroplasty, joint kinematics must be maintained amid bone and ligamentous insufficiency. Current modular designs address defects while allowing for intraoperative prosthesis customization through a variety of stem extensions and constraints. Additional constraint improves knee stability while increasing stress at the implant-host interface and modular junction of the implant. This renders the prosthetic stem-condyle junction more prone to fatigue failure. We report 2 cases of prosthetic stem-condyle junction failure in in a varus-valgus constrained revision total knee arthroplasty.

Hip Arthroplasty in Patients with Osteogenesis Imperfecta

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Osteogenesis imperfecta (OI) is a rare congenital disorder that affects connective tissue.

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Modern medicine has mitigated the mortality that is associated with OI, allowing patients to live a near-normal life span.

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The degenerative process in OI is probably accelerated because of subclinical intra-articular fractures, joint laxity, and distorted femoral and acetabular anatomy.

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Total hip arthroplasty is seldom performed in patients with OI; it is technically difficult due to bone fragility, deformity, soft-tissue alteration, acetabular protrusion, the risk of intraoperative and postoperative fractures, and joint laxity.

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This review highlights that patients with OI need hip arthroplasty procedures at an early age and that early revision surgery can be expected. New-generation uncemented implants may improve implant survivorship.

The Effect of a Distal Centralizer on Cemented Femoral Stems in Arthroplasty Shown on Radiographs and SPECT/CT: A Case Report

CASE

A 70-year-old female patient underwent total hip arthroplasty (HA) using a stem cemented line-to-line without centralizer. Postoperatively, she complained of load-dependent thigh pain. Conventional radiographs identified cortical overload because of a distal cement mantle discontinuity at the level of the stem's tip, confirmed by single-photon emission computed tomography/computed tomography scan (SPECT/CT). After cement-in-cement revision using a stem with centralizer, pain ceased rapidly. The cortical overload disappeared, as confirmed on a following SPECT/CT performed for low back pain.

CONCLUSION

In HA, the stem's tip may cause overload on the bone's cortex if the cement mantle is incomplete. Implanting a stem with centralizer avoids or cures this.

Lockdown-Related Disparities Experienced by People with Disabilities during the First Wave of the COVID-19 Pandemic: Scoping Review with Thematic Analysis

People with disabilities may be disproportionally affected by the COVID-19 pandemic. We synthesize the literature on broader health and social impacts on people with disabilities arising from lockdown-related measures.

METHODS

Scoping review with thematic analysis. Up to mid-September 2020, seven scientific databases and three pre-print servers were searched to identify empirical or perspective papers addressing lockdown-related disparities experienced by people with disabilities. Snowballing searches and experts' consultation also occurred. Two independent reviewers took eligibility decisions and performed data extractions.

RESULTS

Out of 1026 unique references, 85 addressed lockdown-related disparities experienced by people with disabilities. Ten primary and two central themes were identified: (1) Disrupted access to healthcare (other than for COVID-19); (2) Reduced physical activity leading to health and functional decline; (3) From physical distance and inactivity to social isolation and loneliness; (4) Disruption of personal assistance and community support networks; (5) Children with disabilities disproportionally affected by school closures; (6) Psychological consequences of disrupted routines, activities, and support; (7) Family and informal caregiver burden and stress; (8) Risks of maltreatment, violence, and self-harm; (9) Reduced employment and/or income exacerbating disparities; and (10) Digital divide in access to health, education, and support services. Lack of disability-inclusive response and emergency preparedness and structural, pre-pandemic disparities were the central themes.

CONCLUSIONS

Lockdown-related measures to contain the COVID-19 pandemic can disproportionally affect people with disabilities with broader impact on their health and social grounds. Lack of disability-inclusive response and emergency preparedness and pre-pandemic disparities created structural disadvantages, exacerbated during the pandemic. Both structural disparities and their pandemic ramifications require the development and implementation of disability-inclusive public health and policy measures.

Osteoarthritis care and risk of total knee arthroplasty among medicare beneficiaries

OBJECTIVE

To examine health care utilization among patients with knee osteoarthritis and test if utilization differed among residents of regions with high and low rates of total knee arthroplasty (TKA).

DESIGN

This was a retrospective cohort study of U.S. Medicare beneficiaries in 2005 - 2010 with knee osteoarthritis. Health care utilization for knee complaints, including rates of physician visits, physical therapy, knee injections and arthroscopy were abstracted from claims files until TKA or the end of study in 2015. Utilization was compared among beneficiaries who lived in regions with high or low rates of TKA.

RESULTS

Among 988,570 beneficiaries with knee osteoarthritis, 327,499 beneficiaries (33.1%) had TKA during follow-up (median 5.6 years). Higher rates of visits for knee complaints were associated with increased risks of arthroplasty, while use of physical therapy, specialist care, and intra-articular treatments were associated with lower risks. Frequency of TKA varied from 26.4% in the lowest quintile region to 42.1% in the highest quintile. Rates of physician visits, physical therapy, specialist care, and use of intra-articular injections varied inversely with arthroplasty quintile. For example, physical therapy was used by 32.5% of beneficiaries in the lowest quintile region and 23.6% in the highest quintile region. Physical therapy was associated with lower TKA rates across all quintiles.

CONCLUSIONS

Dedicated non-surgical osteoarthritis care was infrequently used by elderly Americans with knee osteoarthritis. Non-surgical care was more common in regions with low rates of TKA, suggesting reciprocal emphasis on medical versus surgical treatment across regions.

Preoperative risk stratification minimizes 90-day complications in morbidly obese patients undergoing primary total knee arthroplasty

AIMS

It has been shown that the preoperative modification of risk factors associated with obesity may reduce complications after total knee arthroplasty (TKA). However, the optimal method of doing so remains unclear. The aim of this study was to investigate whether a preoperative Risk Stratification Tool (RST) devised in our institution could reduce unexpected intensive care unit (ICU) transfers and 90-day emergency department (ED) visits, readmissions, and reoperations after TKA in obese patients.

METHODS

We retrospectively reviewed 1,614 consecutive patients undergoing primary unilateral TKA. Their mean age was 65.1 years (17.9 to 87.7) and the mean BMI was 34.2 kg/m² (SD 7.7). All patients underwent perioperative optimization and monitoring using the RST, which is a validated calculation tool that provides a recommendation for postoperative ICU care or increased nursing support. Patients were divided into three groups: non-obese (BMI < 30 kg/m², n = 512); obese (BMI 30 kg/m² to 39.9 kg/m², n = 748); and morbidly obese (BMI > 40 kg/m², n = 354). Logistic regression analysis was used to evaluate the outcomes among the groups adjusted for age, sex, smoking, and diabetes.

RESULTS

Obese patients had a significantly increased rate of discharge to a rehabilitation facility compared with non-obese patients (38.7% (426/1,102) vs 26.0% (133/512), respectively; p < 0.001). When stratified by BMI, discharge to a rehabilitation facility remained significantly higher compared with non-obese (26.0% (133)) in both obese (34.2% (256), odds ratio (OR) 1.6) and morbidly obese (48.0% (170), OR 3.1) patients (p < 0.001). However, there was no significant difference in unexpected ICU transfer (0.4% (two) non-obese vs 0.9% (seven) obese (OR 2.5) vs 1.7% (six) morbidly obese (OR 5.4); p = 0.054), visits to the ED (8.6% (44) vs 10.3% (77) (OR 1.3) vs 10.5% (37) (OR 1.2); p = 0.379), readmissions (4.5% (23) vs 4.0% (30) (OR 1.0) vs 5.1% (18) (OR 1.4); p = 0.322), or reoperations (2.5% (13) vs 3.3% (25) (OR 1.2) vs 3.1% (11) (OR 0.9); p = 0.939).

CONCLUSION

With the use of a preoperative RST, morbidly obese patients had similar rates of short-term postoperative adverse outcomes after primary TKA as non-obese patients. This supports the assertion that morbidly obese patients can safely undergo TKA with appropriate perioperative optimization and monitoring. Cite this article: Bone Joint J 2021;103-B(6 Supple A):45-50.

Manipulation under anaesthesia after primary total knee arthroplasty : minimal differences in intravenous sedation alone versus neuraxial anaesthesia

AIMS

Manipulation under anaesthesia (MUA) remains an effective intervention to address restricted range of motion (ROM) after total knee arthroplasty (TKA) and occurs in 2% to 3% of primary TKAs at our institution. Since there are few data on the outcomes of MUA with different anaesthetic methods, we sought to compare the outcomes of patients undergoing MUA with intravenous (IV) sedation and neuraxial anaesthesia.

METHODS

We identified 548 MUAs after primary TKA (136 IV sedation, 412 neuraxial anaesthesia plus IV sedation) from March 2016 to July 2019. The mean age of this cohort was 62 years (35 to 88) with a mean body mass index of 31 kg/m² (18 to 49). The mean time from primary TKA to MUA was 10.2 weeks (6.2 to 24.3). Pre-MUA ROM was similar between groups; overall mean pre-MUA extension was 4.2° (p = 0.452) and mean pre-MUA flexion was 77° (p = 0.372). We compared orthopaedic complications, visual analogue scale (VAS) pain scores, length of stay (LOS), and immediate and three-month follow-up knee ROM between these groups.

RESULTS

Following MUA, patients with IV sedation had higher mean VAS pain scores of 5.2 (SD 1.8) compared to 4.1 (SD = 1.5) in the neuraxial group (p < 0.001). The mean LOS was shorter in patients that received IV sedation (9.5 hours (4 to 31)) compared to neuraxial anaesthesia (11.9 hours (4 to 51)) (p = 0.009), but an unexpected overnight stay was similar in each group (8.6%). Immediate-post MUA ROM was 1° to 121° in the IV sedation group and 0.9° to 123° in the neuraxial group (p = 0.313). Three-month follow-up ROM was 2° to 108° in the IV sedation group and 1.9° to 110° in the neuraxial anaesthesia group (p = 0.325) with a mean loss of 13° (ranging from 5° gain to 60° loss), in both groups by three months. No patients in either group sustained a complication.

CONCLUSION

IV sedation alone and neuraxial anaesthesia are both effective anaesthetic methods for MUA after primary TKA. Surgeons and anaesthetists should offer these anaesthetic techniques to match patient-specific needs as the orthopaedic outcomes are similar. Also, patients should be counselled that ROM following MUA may decrease over time. Cite this article: Bone Joint J 2021;103-B(6 Supple A):126-130.

2021 Chitranjan S. Ranawat Award: Intraosseous vancomycin reduces periprosthetic joint infection in primary total knee arthroplasty at 90-day follow-up

AIMS

Infection complicating primary total knee arthroplasty (TKA) is a common reason for revision surgery, hospital readmission, patient morbidity, and mortality. Increasing incidence of methicillin-resistant Staphylococcus aureus (MRSA) is a particular concern. The use of vancomycin as prophylactic agent alone or in combination with cephalosporin has not demonstrated lower periprosthetic joint infection (PJI) rates, partly due to timing and dosing of intravenous (IV) vancomycin administration, which have proven important factors in effectiveness. This is a retrospective review of a consecutive series of primary TKAs examining incidence of PJI, adverse reactions, and complications using IV versus intraosseous (IO) vancomycin at 30-day, 90-day, and one-year follow-up.

METHODS

A retrospective review of 1,060 patients who underwent TKA between May 2016 to July 2020 was performed. There were 572 patients in the IV group and 488 in the IO group, with minimal 30 days of follow-up. Patients were followed up at regularly scheduled intervals (two, six, and 12 weeks). No differences between groups for age, sex, BMI, or baseline comorbidities existed. The IV group received an IV dose of 15 mg/kg vancomycin given over an hour preceding skin incision. The IO group received a 500 mg dose of vancomycin mixed in 150 ml of normal saline, injected into proximal tibia after tourniquet inflation, before skin incision. All patients received an additional dose of first generation cephalosporin. Evaluation included preoperative and postoperative serum creatinine values, tourniquet time, and adverse reactions attributable to vancomycin.

RESULTS

Incidence of PJI with minimum 90-day follow-up was 1.4% (eight knees) in the IV group and 0.22% (one knee) in IO group (p = 0.047). This preliminary report demonstrated an reduction in the incidence of infection in TKA using IO vancomycin combined with a first-generation cephalosporin. While the study suffers from limitations of a retrospective, multi-surgeon investigation, early findings are encouraging.

CONCLUSION

IO delivery of vancomycin after tourniquet inflation is a safe and effective alternative to IV administration, eliminating the logistical challenges of timely dosing. Cite this article: Bone Joint J 2021;103-B(6 Supple A):13-17.

Social determinants of health in total knee arthroplasty : are social factors associated with increased 30-day post-discharge cost of care and length of stay?

AIMS

Social determinants of health (SDOHs) may contribute to the total cost of care (TCOC) for patients undergoing total knee arthroplasty (TKA). The aim of this study was to investigate the association between demographic data, health status, and SDOHs on 30-day length of stay (LOS) and TCOC after this procedure.

METHODS

Patients who underwent TKA between 1 January 2018 and 31 December 2019 were identified. A total of 234 patients with complete SDOH data were included. Data were drawn from the Chesapeake Regional Information System, the Centers for Disease Control social vulnerability index (SVI), the US Department of Agriculture, and institutional electronic medical records. The SVI identifies areas vulnerable to catastrophic events with four themed scores: socioeconomic status; household composition and disability; minority status and language; and housing and transportation. Food deserts were defined as neighbourhoods located one or ten miles from a grocery store in urban and rural areas, respectively. Multiple regression analyses were performed to determine associations with LOS and costs after controlling for various demographic parameters.

RESULTS

Divorced status was significantly associated with an increased LOS (p = 0.043). Comorbidities significantly associated with an increased LOS included chronic obstructive pulmonary disease/asthma and congestive heart failure (p = 0.043 and p = 0.001, respectively). Communities with a higher density of tobacco stores were significantly associated with an increased LOS (p = 0.017). Comorbidities significantly associated with an increased TCOC included chronic obstructive pulmonary disease (p = 0.004), dementia (p = 0.048), and heart failure (p = 0.007). Increased TCOCs were significantly associated with patients who lived in food deserts (p = 0.001) and in areas with an increased density of tobacco stores (p = 0.023).

CONCLUSION

Divorced marital status was significantly associated with an increased LOS following TKA. Living in food deserts and in communities with more tobacco stores were significant risk factors for increased LOS and TCOC. Food access and ease of acquiring tobacco may both prove to be prognostic of outcome after TKA and an opportunity for intervention. Cite this article: Bone Joint J 2021;103-B(6 Supple A):113-118.

Discontinuation of the liposomal delivery of bupivacaine has no effect on pain management after primary total knee arthroplasty : no effect on pain scores, opioid consumption, or functional status

AIMS

Liposomal bupivacaine (LB) as part of a periarticular injection protocol continues to be a highly debated topic in total knee arthroplasty (TKA). We evaluated the effect of discontinuing the use of LB in a periarticular protocol on immediate postoperative pain scores, opioid consumption, and objective functional outcomes.

METHODS

On 1 July 2019, we discontinued the use of intraoperative LB as part of a periarticular injection protocol. A consecutive group of patients who received LB as part of the protocol (Protocol 1) and a subsequent group who did not (Protocol 2) were compared. All patients received the same opioid-sparing protocol. Verbal rating scale (VRS) pain scores were collected from our electronic data warehouse and averaged per patient per 12-hour interval. Events relating to the opiate administration were derived as morphine milligram equivalences (MMEs) per patient per 24-hour interval. The Activity Measure for Post-Acute Care (AM-PAC) tool was used to assess the immediate postoperative function.

RESULTS

A total of 888 patients received Protocol 1 and while 789 received Protocol 2. The mean age of the patients was significantly higher in those who did not receive LB (66.80 vs 65.57 years, p = 0.006). The sex, BMI, American Society of Anesthesiologists physical status score, race, smoking status, marital status, operating time, length of stay, and discharge disposition were similar in the two groups. Compared with the LB group, discontinuing LB showed no significant difference in postoperative VRS pain scores up to 72 hours (p > 0.05), opioid administration up to 96 hours (p > 0.05), or AM-PAC scores within the first 24 hours (p > 0.05).

CONCLUSION

The control of pain after TKA with a multimodal management protocol is not improved by the addition of LB compared with traditional bupivacaine. Cite this article: Bone Joint J 2021;103-B(6 Supple A):102-107.

Comparison of 2013 and 2009 versions of Caprini risk assessment models for predicting VTE in Chinese cancer patients: a retrospective study

This study aimed to compare the predictive value of 2009 and 2013 version of Caprini risk assessment models (RAM) for venous thromboembolism (VTE) in cancer patients by receiver operating characteristic (ROC) analysis. This retrospective study reviewed a total of 1439 VTE and 1439 non-VTE Chinese cancer inpatients. The baseline demographic data of these patients were recorded. 2009 and 2013 versions Caprini RAMs were applied, and cumulative risk scores were obtained by adding the scores of each risk factor. The specificity, sensitivity, positive predictive value and negative predictive value of these two models were analyzed. ROC curve was drawn to calculate the area under the curve (AUC) and the Youden index. Significant differences were observed in the risk factors between VTE and non-VTE Group. The specificity and negative predictive value of 2013 version were higher than those of 2009 version (P < 0.05). No significant differences were found in the sensitivity or positive predictive value between 2009 and 2013 versions of the Caprini RAM (P > 0.05). The AUC and Youden index of 2013 Caprini RAM were significantly higher than those of 2009 Caprini RAM (P < 0.001), whereas the Youden index of the 2009 Caprini RAM at critical point 4 was higher than that at critical point 3 (0.362 vs 0.067, P < 0.05). Compared with 2009 version, 2013 version of the Caprini RAM provides a more accurate and efficacious method for the risk assessment of VTE in Chinese cancer patients.

2021 Mark Coventry Award: Use of a smartphone-based care platform after primary partial and total knee arthroplasty: a prospective randomized controlled trial

AIMS

The purpose is to determine the non-inferiority of a smartphone-based exercise educational care management system after primary knee arthroplasty compared with a traditional in-person physiotherapy rehabilitation model.

METHODS

A multicentre prospective randomized controlled trial was conducted evaluating the use of a smartphone-based care management system for primary total knee arthroplasty (TKA) and partial knee arthroplasty (PKA). Patients in the control group (n = 244) received the respective institution's standard of care with formal physiotherapy. The treatment group (n = 208) were provided a smartwatch and smartphone application. Early outcomes assessed included 90-day knee range of movement, EuroQoL five-dimension five-level score, Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) score, 30-day single leg stance (SLS) time, Time up and Go (TUG) time, and need for manipulation under anaesthesia (MUA).

RESULTS

Overall, 90-day mean flexion was not significantly different between the control (121° (SD 11.7°)) and treatment groups (121^o; p = 0.559); 90-day mean SLS was 22.7 seconds (SD 9.8) in controls and 24.3 seconds (SD 20.8) in treatment (p = 0.519); 90-day mean TUG times were 10.1 seconds (SD 4.8) in control and 9.3 seconds (SD 3.3) in treatment (p = 0.139). Mean KOOS JR scores were significantly different between control group (73.6 (SD 13.4)) and treatment group (70.4 (SD 12.6); p = 0.026). MUAs were performed in nine (3.7%) patients in the control group and four (1.9%) in the treatment group (p = 0.398). Physiotherapy was performed by 230 (94.4%) of control group and 123 (59.3%) of treatment group (p < 0.001). There were no significant differences between groups in postoperative urgent care visits, or readmissions within 90 days, with significantly fewer emergency department visits in the treatment group (16 (8.2%) vs five (2.5%), p = 0.014).

CONCLUSION

The use of the smartwatch/smartphone care platform demonstrated non-inferiority of clinically significant outcomes to traditional care models, while requiring significantly less postoperative physiotherapy and fewer emergency department visits. This platform could aid in decreasing postoperative costs, while improving patient engagement and communication with the healthcare team. Cite this article: Bone Joint J 2021;103-B(6 Supple A):3-12.

Excellent mid-term follow-up for a new 3D-printed cementless total knee arthroplasty

AIMS

Cementless total knee arthroplasty (TKA) offers the potential for strong biological fixation compared with cemented TKA where fixation is achieved by the mechanical integration of the cement. Few mid-term results are available for newer cementless TKA designs, which have used additive manufacturing (3D printing). The aim of this study was to present mid-term clinical outcomes and implant survivorship of the cementless Stryker Triathlon Tritanium TKA.

METHODS

This was a single institution registry review of prospectively gathered data from 341 cementless Triathlon Tritanium TKAs at four to 6.8 years follow-up. Outcomes were determined by comparing pre- and postoperative Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) scores, and pre- and postoperative 12-item Veterans RAND/Short Form Health Survey (VR/SF-12) scores. Aseptic loosening and revision for any reason were the endpoints which were used to determine survivorship at five years.

RESULTS

At mid-term follow-up, the mean KOOS JR score improved significantly from 33.14 (0 t0 85, standard deviation (SD) 21.88) preoperatively to 84.12 (15.94 to 100, SD 20.51) postoperatively (p < 0.001), the mean VR/SF-12 scores improved significantly from physical health (PH), 31.21 (SD 5.32; 23.99 to 56.77) preoperatively to 42.62 (SD 10.72; 19.38 to 56.82) postoperatively (p < 0.001) and the mental health (MH), 38.15 (SD 8.17; 19.06 to 60.75) preoperatively to 55.09 (SD 9.64; 19.06 to 66.98) postoperatively (p < 0.001). A total of 11 revisions were undertaken, with an overall revision rate of 2.94%, including five for periprosthetic joint infection (1.34%), three for loosening (0.80%), two for instability (0.53%), and one for pain (0.27%). The overall survivorship was 97.06% and survivorship for aseptic loosening as the endpoint was 98.40%, with a 99.5% survivorship of the 3D-printed tibial component.

CONCLUSION

This 3D-printed cementless total knee system shows excellent survivorship at mid-term follow-up. This design and the ability to obtain cementless fixation offers promise for excellent long-term durability. Cite this article: Bone Joint J 2021;103-B(6 Supple A):32-37.

Patient satisfaction following total knee arthroplasty using restricted kinematic alignment

AIMS

Alternative alignment concepts, including kinematic and restricted kinematic, have been introduced to help improve clinical outcomes following total knee arthroplasty (TKA). The purpose of this study was to evaluate the clinical results, along with patient satisfaction, following TKA using the concept of restricted kinematic alignment.

METHODS

A total of 121 consecutive TKAs performed between 11 February 2018 to 11 June 2019 with preoperative varus deformity were reviewed at minimum one-year follow-up. Three knees were excluded due to severe preoperative varus deformity greater than 15°, and a further three due to requiring revision surgery, leaving 109 patients and 115 knees to undergo primary TKA using the concept of restricted kinematic alignment with advanced technology. Patients were stratified into three groups based on the preoperative limb varus deformity: Group A with 1° to 5° varus (43 knees); Group B between 6° and 10° varus (56 knees); and Group C with varus greater than 10° (16 knees). This study group was compared with a matched cohort of 115 TKAs and 115 patients using a neutral mechanical alignment target with manual instruments performed from 24 October 2016 to 14 January 2019.

RESULTS

Mean overall patient satisfaction for the entire cohort was 4.7 (SE 0.1) on a 5-point Likert scale, with 93% being either very satisfied or satisfied compared with a Likert of 4.3 and patient satisfaction of 81% in the mechanical alignment group (p < 0.001 and p < 0.006 respectively). At mean follow-up of 17 months (11 to 27), the mean overall Likert, Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, Western Ontario and McMaster Universities Osteoarthritis Index, Forgotten Joint Score, and Knee Society Knee and Function Scores were significantly better in the kinematic group than in the neutral mechanical alignment group. The most common complication in both groups was contracture requiring manipulation under anaesthesia, involving seven knees (6.1%) in the kinematic group and nine knees (7.8%) in the mechanical alignment group.

CONCLUSION

With the advent of advanced technology, and the ability to obtain accurate bone cuts, the target limb alignment, and soft-tissue balance within millimetres, using a restricted kinematic alignment concept demonstrated excellent patient satisfaction following primary TKA. Longer-term analysis is required as to the durability of this method. Cite this article: Bone Joint J 2021;103-B(6 Supple A):59-66.

Direct anterior approach has short-term functional benefit and higher resource requirements compared with the posterior approach in primary total hip arthroplasty : a meta-analysis of functional outcomes and cost

AIMS

It has been suggested that the direct anterior approach (DAA) should be used for total hip arthroplasty (THA) instead of the posterior approach (PA) for better early functional outcomes. We conducted a value-based analysis of the functional outcome and associated perioperative costs, to determine which surgical approach gives the better short-term outcomes and lower costs.

METHODS

This meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol and the Cochrane Handbook. Several online databases were searched. Non-stratified and stratified meta-analyses were conducted to test the confounding biases in the studies which were included. The mean cost and probability were used to determine the added costs of perioperative services.

RESULTS

The DAA group had significantly longer operating times (p < 0.001), reduced length of hospital stay by a mean of 13.4 hours (95% confidence interval (CI) 9.12 to 18; p < 0.001), and greater blood loss (p = 0.030). The DAA group had significantly better functional outcome at three (p < 0.001) and six weeks (p = 0.006) postoperatively according to the Harris Hip Score (HHS). However, there was no significant difference between the groups for the HHS at six to eight weeks (p = 0.230), 12 weeks (p = 0.470), six months (p = 0.740), and one year (p = 0.610), the 12-Item Short Form Survey (SF-12) physical score at six weeks (p = 0.580) and one year (p = 0.360), SF-12 mental score at six weeks (p = 0.170) and one year (p = 0.960), and University of California and Los Angeles (UCLA) activity scale at 12 weeks (p = 0.250). The mean non-stratified and stratified difference in costs for the operating theatre time and blood transfusion were $587.57 (95% CI 263.83 to 1,010.29) to $887.04 (95% CI 574.20 to 1,298.88) and $248.38 (95% CI 1,003.40 to 1,539.90) to $1,162.41 (95% CI 645.78 to 7,441.30), respectively, more for the DAA group. However, the mean differences in costs for the time in hospital were $218.23 and $192.05, respectively, less for the DAA group.

CONCLUSION

The use of the DAA, rather than the PA, in THA has earlier benefits for function and pain. However, these are short-lasting, with no significant differences seen at later intervals. In addition the limited benefits were obtained with higher cumulative costs for DAA. Cite this article: Bone Joint J 2021;103-B(6):1078-1087.

Dual Modular Titanium Alloy Femoral Stem Failure Mechanisms and Suggested Clinical Approaches

Titanium (Ti) alloys have been proven to be one of the most suitable materials for orthopaedic implants. Dual modular stems have been introduced to primary total hip arthroplasty (THA) to enable better control of the femoral offset, leg length, and hip stability. This systematic review highlights information acquired for dual modular Ti stem complications published in the last 12 years and offers a conclusive discussion of the gathered knowledge. Articles referring to dual modular stem usage, survivorship, and complications in English were searched from 2009 to the present day. A qualitative synthesis of literature was carried out, excluding articles referring solely to other types of junctions or problems with cobalt-chromium alloys in detail. In total, 515 records were identified through database searching and 78 journal articles or conference proceedings were found. The reasons for a modular neck fracture of a Ti alloy are multifactorial. Even though dual modular stems have not shown any clinical benefits for patients and have been associated with worse results regarding durability than monolithic stems, some designs are still marketed worldwide. Orthopaedic surgeons should use Ti6Al4V dual modular stem designs for primary THA in special cases only.

Incidence of COVID-19 After Nonelective Hip and Knee Surgery During the Peak of the Pandemic: The New Jersey Experience

In an attempt to preserve essential equipment and health care system capacity and slow the spread of coronavirus disease 2019 (COVID-19) infection, Governor Murphy suspended all elective surgeries performed in New Jersey from March 27, 2020, through May 25, 2020. The objective of this study was to determine the incidence of postoperative COVID-19 infection following nonelective hip and knee surgery during the peak of the COVID-19 pandemic in New Jersey during this time. A retrospective cohort of 149 patients who underwent nonelective hip and knee surgery from March 27, 2020, through May 25, 2020, at 2 institutions was identified. The cohort was divided into hip fracture and non-fracture patients to compare the postoperative experience of these patient populations. The primary outcome was the incidence of postoperative COVID-19 infection diagnosed via severe acute respiratory syndrome coronavirus 2 nasopharyngeal real-time reverse transcription polymerase chain reaction. Secondary outcomes included length of stay, discharge disposition, postoperative complications, and mortality rate. A total of 149 patients underwent nonelective hip and knee surgeries, including 76 hip fracture cases and 73 nonelective hip and knee arthroplasty cases. A postoperative diagnosis of COVID-19 was made for 5 (6.6%) of 76 hip fracture patients, and 2 of the 5 died secondary to COVID-19. There were no infections in the arthroplasty cohort. This study describes a low incidence of COVID-19 infection after nonelective hip and knee surgery during the surge of the COVID-19 pandemic in New Jersey. Patients who underwent hip fracture surgery had an increased incidence of postoperative COVID-19 infection. [Orthopedics. 2021;44(3):180-186.].

Wear Assessment of Tibial Inserts Made of Highly Cross-Linked Polyethylene Supplemented with Dodecyl Gallate in the Total Knee Arthroplasty

Background: the wear of tibial insert is still one of primary factors leading to failure of total knee arthroplasty (TKA). Dodecyl gallate (DG) has shown improvements in the oxidation stability of highly cross-linked polyethylene (HXLPE). This study aimed to assess the application of HXLPE supplemented with DG (HXLPE-DG) on the tibial insert in TKA concerning the wear resistance and the potential impact on implant fixation; Methods: tibial inserts made of HXLPE-DG were subjected to a 3 million loading-cycle wear test following ISO 14243-1:2009. The loss of mass and wear rate of the tibial inserts were calculated. The quantity, size,- and shape of wear particles were recorded; Results: the test specimens lost an average mass of 16.00 mg ± 0.94 mg, and were on an average wear rate of 3.92 mg/million cycles ± 0.19 mg/million cycles. The content of wear particles in the calf serum medium was 3.94 × 10⁸ particles/mL ± 3.93 × 10⁷ particles/mL, 96.66% ± 0.77% of the particles had an equivalent circular diameter less than 0.5 μm. The aspect ratio of wear particles was 1.40 (min: 1.01; max: 6.42). Conclusions: HXLPE-DG displayed advantages over the commonly used materials for tibial inserts and presented the potential of application in TKA.

Factors Influencing Press Ganey Ambulatory Surgery Scores in Patients Undergoing Upper Extremity Procedures

We sought to determine whether patient and surgical factors are associated with the Press Ganey Ambulatory Surgery Survey (PGAS) satisfaction scores in patients undergoing outpatient upper extremity procedures.

Implant survival of 2,723 vitamin E-infused highly crosslinked polyethylene liners in total hip arthroplasty: data from the Finnish Arthroplasty Register

Background and purpose - The use of crosslinked polyethylene in total hip arthroplasty (THA) has decreased wear remarkably. It has been suggested that the antioxidative effects of vitamin E may enhance the wear properties of polyethylene even further. This study evaluates revision rates between vitamin E-infused polyethylene liners (E1 and E-poly, ZimmerBiomet, Warsaw, IN, USA) versus moderately crosslinked polyethylene (ModXLPE) liners from the same manufacturer used in primary THA.Patients and methods - We conducted a study based on data from the Finnish Arthroplasty Register. The study group consisted of 2,723 THAs with a vitamin E-infused liner and a reference group of 2,707 THAs with a moderately crosslinked polyethylene liner. Survivorship, revision risk, and re-revision causes were compared between groups.Results - The 7-year survival of the vitamin E-infused polyethylene liner group and of the reference group with revision for any reason as the endpoint was comparable (94% [95% CI 92.9-94.9] and 93% [CI 91.9-93.9], respectively). The adjusted hazard ratio (HR) for any revision was similar between the groups (0.7 [CI 0.4-1.1]). When revision for aseptic loosening was studied as the endpoint, the survival for the study group was 99% (CI 98.6-99.4) and for the reference group 99% (CI 98.7-99.5), and the risk of revision was comparable between the study groups (HR 1.3 [CI 0.7-2.5]).Interpretation - After an observation period of 7 years vitamin E-infused liners shows results equal to results obtained with crosslinked polyethylene liners.

Cobalt-induced cardiomyopathy - do circulating cobalt levels matter?

Elevated levels of circulating cobalt ions have been linked with a wide range of systemic complications including neurological, endocrine, and cardiovascular symptoms. Case reports of patients with elevated blood cobalt ions have described significant cardiovascular complications including cardiomyopathy. However, correlation between the actual level of circulating cobalt and extent of cardiovascular injury has not previously been performed. This review examines evidence from the literature for a link between elevated blood cobalt levels secondary to metal-on-metal (MoM) hip arthroplasties and cardiomyopathy. Correlation between low, moderate, and high blood cobalt with cardiovascular complications has been considered. Elevated blood cobalt at levels over 250 µg/l have been shown to be a risk factor for developing systemic complications and published case reports document cardiomyopathy, cardiac transplantation, and death in patients with severely elevated blood cobalt ions. However, it is not clear that there is a hard cut-off value and cardiac dysfunction may occur at lower levels. Clinical and laboratory research has found conflicting evidence of cobalt-induced cardiomyopathy in patients with MoM hips. Further work needs to be done to clarify the link between severely elevated blood cobalt ions and cardiomyopathy.

Cite this article: Bone Joint Res 2021;10(6):340–347.

Trends and Outcomes of Hip Fracture Hospitalization Among Medicare Beneficiaries with Inflammatory Bowel Disease, 2000-2017

BACKGROUND

Patients with inflammatory bowel disease (IBD) have a higher risk of hip fracture, but lower likelihood of having arthroplasties than non-IBD patients in Nationwide Inpatient Sample. Little is known about hip fracture-associated hospitalization outcomes.

AIMS

We assessed the trends in hip fracture hospitalization rates from 2000 to 2017 and estimated 30-day readmission, 30-day mortality, and length of stay in 2016 and 2017.

METHODS

We estimated trends of age-adjusted hospitalization rates using a piecewise linear regression. Medicare beneficiaries aged ≥ 66 years with Crohn's disease (CD, n = 2014) or ulcerative colitis (UC, n = 2971) hospitalized for hip fracture were identified. We performed propensity score matching to create 1:3 matched samples on age, race/ethnicity, sex, and chronic conditions and compared hospitalization outcomes between matched samples.

RESULTS

In 2017, the age-adjusted hospitalization rates (per 100) were 1.15 [95% CI = (1.07-1.24)] for CD, 0.86 [95% CI = (0.82-0.89)] for UC, and 0.59 [95% CI = (0.59-0.59)] for no IBD. The hospitalization rates for CD and UC decreased from 2000 to 2012 and then increased from 2012 to 2017. Compared to matched cohorts, CD patients had longer hospital stays (5.55 days vs. 5.30 days, p = 0.01); UC patients were more likely to have 30-day readmissions (17.27% vs. 13.71%, p < 0.001), longer hospital stays (5.59 days vs. 5.40 days, p = 0.02), and less likely to have 30-day mortality (3.77% vs. 5.15%, p = 0.003).

CONCLUSIONS

Prevention of hip fracture is important for older adults with IBD, especially CD. Strategies that improve quality of inpatient care for IBD patients hospitalized for hip fracture should be considered.

Assessment of the hyperbaric oxygen therapy effects in distal femoral necrosis using hyperspectral imaging

Introduction. Hyperbaric oxygen therapy is a treatment option for an increasing number of conditions. The aim of this study was to assess its therapeutic effects in femoral condylar necrosis as well as in normal tissue using hyperspectral imaging. Material and method. A 47-year-old female patient diagnosed with avascular necrosis of the medial femoral condyle was included in this study. The patient received hyperbaric oxygen therapy for two consecutive days (the first day: three stages of 30 min each, separated by two breaks of 5 min at pO2 = 2 ATA; the second day: three stages of 30 min each, separated by two breaks of 5 min at pO2 = 2.4 ATA). The effects of hyperbaric oxygen therapy on the affected area (patient’s knee) and normal (patient’s hand) tissues oxygenation were assessed before and after each treatment session using hyperspectral imaging. Results and discussions. The results showed that hyperspectral imaging is quite good for monitoring the hyperbaric oxygen therapy efficacy in affected areas, even with deep tissue problems. Conclusions. In conclusion, the hyperspectral imaging-based approach for monitoring hyperbaric oxygen therapy could support physicians in extracting prognostic information and making the right treatment decisions. Keywords: bone necrosis, image analysis, maps, oxyhemoglobin, deoxyhemoglobin, oxygen saturation,

Revision knee arthroplasty: Can good outcomes be achieved at lower volumes?

BACKGROUND

The National Joint Registry (NJR) demonstrates a re-revision rate for primary knee arthroplasty of 14.2% at 7 years. The 2015 Getting it Right First Time (GIRFT) report highlighted that 58% of surgeons undertaking revision knee arthroplasty (RKA) performed fewer than five cases per year. It has been suggested that revision cases be centralised in specialist centres with a multidisciplinary team (MDT) approach. Such a hub and spoke or cluster models may still require revision surgery to be performed at relatively low volume units.

METHODS

An analysis of RKA surgery performed in a four surgeon, lower volume revision knee unit over 10 years to December 2016 was undertaken. The effect of the introduction of a MDT was reviewed. The minimum follow up was two years. The primary outcome measure was re-revision. Hospital data as well as individual surgeon NJR reports were used to ensure all re-revisions were accounted for. Outcome scores were available for 68% of cases.

RESULTS

There were 192 RKAs performed in 187 patients at a mean (stdev) of 6.3 (5.4) years from the index procedure. The mean age at surgery was 68.2 (10.9) years. Twenty nine (15.5%) patients had died at the time of final review. Twelve (6.3%) cases required a further revision procedure. The commonest complication was stiffness requiring MUA. The overall 7 year survivorship was 94.9% (95% CI 90.2-97.3). The mean Oxford score at 5.4 years was 30.4 (10.4).

CONCLUSIONS

RKA can be reliably performed at lower volume centres with appropriate MDT systems in place.

Removal of Well-Fixed Tibial Cone in Revision Total Knee Arthroplasty-A Uniquely Challenging Yet Necessary Scenario

The number of revision total knee arthroplasties (TKA) performed in the United States continues to increase. While advancements in implant design and surgical technique have led to improved outcomes compared with historical data, these cases remain technically demanding with high rates of aseptic failure and worse patient reported outcome scores compared with primary total knee arthroplasty. One particular problem commonly encountered in revision knee arthroplasty is bone loss, particularly in the epiphyseal region, which negatively impacts the structural integrity of the implants. Various modular metaphyseal sleeves and cones in conjunction with stemmed implants have been designed to enhance metaphyseal fixation, corroborated by multiple studies demonstrating excellent midterm results involving cones, and sleeves. Commercially available revision systems that incorporate metaphyseal cones are currently widely utilized in revision TKA. For tibial defects, both symmetric and asymmetric cone options are available. Excellent midterm results have been reported with use of this device in the setting of severe proximal tibial bone loss in revision TKA surgery. With the enhanced fixation provided by various sleeve and cone augments, implant removal in the setting of recurrent infection or implant failure can be extremely challenging. Consequently, in this work, we sought to describe an algorithmic approach for removing a tibial cone in conjunction with the overlying tibial baseplate. A review of the literature has also been conducted for complex surgical techniques regarding removal of well-fixed implants in revision total knee arthroplasty.

Frailty, Race/Ethnicity, Functional Status, and Adverse Outcomes After Total Hip/Knee Arthroplasty: A Moderation Analysis

BACKGROUND

Although frailty has been shown to be associated with adverse outcomes in patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA), prior studies have not examined how race/ethnicity might moderate these associations. We aimed to assess race/ethnicity as a potential moderator of the associations of frailty and functional status with arthroplasty outcomes.

METHODS

The National Surgical Quality Improvement Program was queried for patients who underwent THA or TKA from 2011 to 2017. Frailty was assessed using the modified frailty index. Regression analyses were conducted to examine associations connecting frailty/functional status with 30-day readmission, adverse discharge, and length of stay (LOS). Further analyses were conducted to investigate race/ethnicity as a potential moderator of these relationships.

RESULTS

We identified 219,143 TKA and 130,022 THA patients. Frailty and nonindependent functional status were positively associated with all outcomes (P < .001). Compared to White non-Hispanic patients, Black non-Hispanic patients had higher odds for all outcomes after TKA (P < .001) and for adverse discharge/longer LOS after THA (P < .001). Similar associations were observed for Hispanics for the adverse discharge/LOS outcomes. Race/ethnicity moderated the effects of frailty in TKA for all outcomes and in THA for adverse discharge/LOS. Race/ethnicity moderated the effects of nonindependent function in TKA for adverse discharge/LOS and on LOS alone for THA.

CONCLUSION

Disparities for Black non-Hispanic and Hispanic patients persist for readmission, adverse discharge, and LOS. However, the effects of increasing frailty and nonindependent functional status on these outcomes were the most pronounced among White non-Hispanic patients.

Performance of the HOOS-12 and KOOS-12 instruments for evaluating outcomes from joint replacement surgery

OBJECTIVE

To evaluate the psychometric properties of the 12-item Hip disability and Osteoarthritis Outcome Score (HOOS-12) and Knee injury and Osteoarthritis Outcome Score (KOOS-12) for use in evaluating outcomes after joint replacement for osteoarthritis.

DESIGN

Patient-reported outcomes data collected by the Australian Orthopaedic Association National Joint Replacement Registry were used for this analysis. HOOS-12 and KOOS-12 domain (pain, function, quality of life) and summary impact data were available. The Oxford Hip Score (OHS), Oxford Knee Score (OKS) and EQ-5D-5L were used as comparators. Instruments were administered pre-operatively and at 6 months post-operatively. Internal consistency reliability, floor and ceiling effects, convergent validity, known groups validity, and responsiveness were evaluated using standard psychometric techniques.

RESULTS

Baseline HOOS-12 and KOOS-12 data were available for 3,023 patients undergoing primary total hip replacement and 4,010 patients undergoing primary total knee replacement. At baseline, high internal consistency was demonstrated for all domains and summary scores (Cronbach's alpha: HOOS-12 = 0.81-0.93; KOOS-12 = 0.82-0.92). Post-operative ceiling effects (>15% of patients scoring the best possible score) were identified for the HOOS-12 pain (46%), function (39%) and quality of life domains (26%) and summary score (17%), and for the KOOS-12 pain (21%) and function domains (18%). The HOOS-12 and KOOS-12 could differentiate between two known groups (lowest/highest OHS or OKS quartiles post-operatively; p < 0.001) and were highly responsive to change (effect sizes for HOOS-12: 2.20-2.83; KOOS-12: 1.82-2.35).

CONCLUSION

The HOOS-12 and KOOS-12 have good psychometric properties for capturing joint replacement outcomes including excellent responsiveness, although ceiling effects may limit monitoring of post-operative improvement.

Decreased Opioid Consumption and Length of Stay Using an IPACK and Adductor Canal Nerve Block following Total Knee Arthroplasty

Peripheral nerve blocks such as a femoral + sciatic block have demonstrated significant pain relief following TKA. However, these nerve blocks have residual motor deficits which prevent immediate postoperative ambulation. The purpose of this study was to compare outcomes in patients undergoing primary TKA with femoral and sciatic (Fem + Sci) motor nerve blocks versus an adductor canal and the interspace between the popliteal artery and the capsule of the posterior knee and adductor canal block (IPACK + ACB) sensory nerve blocks. A total of 100 consecutive patients were reviewed, 50 received Fem + Sci nerve blocks and 50 received IPACK + ACB blocks preoperatively. There were no differences in the two groups with respect to surgical technique, implant type, postoperative pain, and physical therapy protocols. Differences in opioid requirements, length of stay (LOS), distance walked, and common knee scoring systems were analyzed. Among them, 62% IPACK + ACB patients were discharged on postoperative day 1 compared with 14% in the Fem + Sci group (p < 0.0001). The IPACK + ACB patients had a shorter LOS (mean 1.48 days vs. 2.02 days, p < 0.001), ambulated further on postoperative day 0 (mean 21.4 feet vs. 5.3 feet, p < 0.001), and required less narcotics the day after surgery (mean, 15.7 vs. 24.0 morphine equivalents p < 0.0001) and at 2 weeks (mean, 6.2 vs. 9.3 morphine equivalents, p = 0.025). The use of this combination IPACK and ACB demonstrated improved early ambulation with a decrease in opioid use and length of stay compared with a femoral and sciatic motor nerve block in patients undergoing primary TKA.

Total Hip and Knee Arthroplasties Are Highly Cost-Effective Procedures: The Importance of Duration of Follow-Up

BACKGROUND

Total hip and knee arthroplasties (THA/TKA) are clinically effective but high cost procedures. The aim of this study is to perform a cost-effectiveness analysis of THA and TKA in the New Zealand (NZ) healthcare system.

METHODS

Data were collected from 713 patients undergoing THA and 520 patients undergoing TKA at our local public hospital. SF-6D utility values were obtained from participants preoperatively and 1-year postoperatively, and deaths and any revision surgeries from patient records and the New Zealand Joint Registry at minimum 8-year follow-up. A continuous-time state-transition simulation model was used to estimate costs and health gains to 15 years. Quality-adjusted life years (QALYs), treatment costs, and incremental cost-effectiveness ratios (ICERs) were calculated to determine cost effectiveness. ICERs below NZ gross domestic product (GDP; NZ$60 600) and 0.5 times GDP per capita were considered "cost effective" and "highly cost effective" respectively.

RESULTS

Cumulative health gains were 2.8 QALYs (THA) and 2.3 QALYs (TKA) over 15 years. Cost effectiveness improved from ICERs of NZ$74,400 (THA) and NZ$93,000 (TKA) at 1 year to NZ$6000 (THA) and NZ$7500 (TKA) at 15 years. THA and TKA were cost effective after 2 years and highly cost effective after 3 years. QALY gains and cost effectiveness were greater in patients with worse preoperative functional status and younger age.

CONCLUSION

THA and TKA are highly cost-effective procedures over longer term horizons. Although preoperative status and age were associated with cost effectiveness, both THA and TKA remained cost effective in patients with less severe preoperative scores and older ages.

Simple Knee Value: a simple evaluation correlated to existing knee PROMs

PURPOSE

The Simple Knee Value (SKV) is an outcome score in which patients are asked to grade their knee function as a percentage of that of a normal knee. The primary aim of this study was to validate the SKV by measuring its correlation with existing knee-related PROMs.

METHODS

This was a prospective study conducted at a teaching hospital to assess the SKV's validity. The study enrolled 47 young patients (16-54 years old), 49 older patients (≥ 55 years) and 30 healthy controls. A paper questionnaire consisting of the Lysholm, IKDC, KOOS, WOMAC and SKV was given to subjects three times (enrolment, 1-month preoperative visit and 6 months postoperative visit). The criterion validity of the SKV was determined by correlating it to existing knee PROMs using the Spearman correlation coefficient (S). SKV test-retest reliability was assessed by the intraclass correlation coefficient (ICC) between two time points (initial consultation at enrolment and preoperative visit, reflecting the same clinical condition). Responsiveness to change was determined by comparing the SKV scores before and after surgery (enrolment consultation and 6 months postoperative). Discriminative ability was determined by comparing the SKV distribution in patients and controls.

RESULTS

There was a strong and significant correlation between the SKV and the gold standard Lysholm, IKDC, KOOS and WOMAC in the younger patients and the older patients (p < 0.0001). The reliability between the SKV at the initial consultation and before surgery was excellent (ICC 0.862, 95% CI 0.765; 0.921) in the younger patients, and moderate (ICC 0.506, 95% CI 0.265; 0.688) in the older patients. The SKV was responsive to change in both patient groups (p < 0.0001 for the SKV before versus 6 months after surgery). Like the other knee-specific PROMs (p < 0.0001), the SKV was able to distinguish between patients and controls (p < 0.0001).

CONCLUSIONS

The SKV is valid as it is significantly correlated to existing knee PROMs. It is also reliable, responsive to change and discriminating. Its simplicity gives it many advantages and it can be used by physicians in their daily practice.

LEVEL OF EVIDENCE

Level II.

International variation in distribution of ASA class in patients undergoing total hip arthroplasty and its influence on mortality: data from an international consortium of arthroplasty registries

Background and purpose - A challenge comparing outcomes from total hip arthroplasty between countries is variation in preoperative characteristics, particularly comorbidity. Therefore, we investigated between-country variation in comorbidity in patients based on ASA class distribution, and determined any variation of ASA class to mortality risk between countries.Patients and methods - All arthroplasty registries collecting ASA class and mortality data in patients with elective primary THAs performed 2012-2016 were identified. Survival analyses of the influence of ASA class on 1-year mortality were performed by individual registries, followed by meta-analysis of aggregated data.Results - 6 national registries and 1 US healthcare organization registry with 418,916 THAs were included. There was substantial variation in the proportion of ASA class III/IV, ranging from 14% in the Netherlands to 39% in Finland. Overall, 1-year mortality was 0.93% (95% CI 0.87-1.01) and increased from 0.2% in ASA class I to 8.9% in class IV. The association between ASA class and mortality measured by hazard ratios (HR) was strong in all registries even after adjustment for age and sex, which reduced them by half in all registries. Combined adjusted HRs were 2.0, 6.1, and 22 for ASA class II-IV vs. I, respectively. Associations were moderately heterogeneous across registries.Interpretation - We observed large variation in ASA class distribution between registries, possibly explained by differences in background morbidity and/or international variation in access to surgery. The similar, strong mortality trends by ASA class between countries enhance the relevance of its use as an indicator of comorbidity in international registry studies.

Alpha-Defensin Is Not Superior to Traditional Diagnostic Methods for Detection of Periprosthetic Joint Infection in Total Hip Arthroplasty and Total Knee Arthroplasty Patients

BACKGROUND

Synovial fluid alpha-defensin (AD) may improve diagnostic accuracy of periprosthetic joint infection (PJI) following total knee (TKA) and hip (THA) arthroplasty but is only available as send-out test. This study evaluated laboratory result accuracy between send-out test vs hospital labs and if AD made a difference in treatment plan.

METHODS

A retrospective review was performed of 152 consecutive patients with a TKA or THA joint aspiration for painful or clinically concerning joint. Synovial fluid was sent to our institution (hospital-based labs, HBL) and send-out immunoassay laboratory (Synovasure). Patients were scored with specific criteria from validated scoring system for PJI using HBL and Synovasure results. The score with and without AD test was compared to determine if AD impacted patient management.

RESULTS

Overall, there was strong agreement between institutions for PJI diagnosis (Cohen's kappa score 0.96). Twenty-nine patients had PJI diagnosis (score ≥6), of which 28 (97%) had positive AD with 1 false-negative result. Sixty-three patients had inconclusive score (between 2 and 5) and 60 patients had negative PJI diagnosis (score ≤1). Of these patients, 5 underwent surgery for infection. Two patients had surgery for positive AD, 2 for positive culture, and 1 because of elevated HBL results. The AD test changed the PJI diagnosis and influenced decision for surgery in only 1.3% (2/152) of patients.

CONCLUSION

Minimal differences were found in laboratory values between institutions. The addition of AD may be useful in cases of equivocal laboratory results but does not appear to be necessary for routine diagnosis of PJI after TKA/THA.

LEVEL EVIDENCE

Level III.

Analysis of the Exeter V40 femoral stem prosthesis fracture : systematic review and single centre case series

Aims

The Exeter V40 cemented polished tapered stem system has demonstrated excellent long-term outcomes. This paper presents a systematic review of the existing literature and reports on a large case series comparing implant fractures between the Exeter V40 series; 125 mm and conventional length stem systems.

Methods

A systematic literature search was performed adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. In parallel, we performed a retrospective single centre study of Exeter V40 femoral stem prosthetic fractures between April 2003 and June 2020.

Results

There are 25 reported cases of such prosthetic fractures confined to small case series and case reports within the literature. We report an additional 19 cases to the literature (mean age 66.3 years (SD 11.7); 12 (63%) females; BMI 32.9 kg/m² (SD 5.9)). The mean time from index procedure to fracture was 7.8 years (SD 3.6; 2.5 to 16.3). Exeter V40 stem fracture incidence was 0.15% and 1.21% for primary and revision arthroplasty, respectively. Incidence was significantly higher in revision arthroplasty (p < 0.001) and 125 mm length stems compared to ≥ 150 mm length stems (1.25% vs 0.13%, respectively; p < 0.001). When comparing different stem length cohorts, 125 mm short-stems were associated with stem-body fractures (92% vs 29%; p = 0.0095), earlier time to fracture (6.2 years vs 11.0 years; p = 0.0018), younger patient age at time of fracture (62.7 years vs 72.6 years; p = 0.037), and female sex (75% vs 43%; p = 0.326).

Conclusion

This complication remains rare, although we report a significantly higher incidence at up to 17 years follow-up than in the literature. Short 125 mm length Exeter V40 stems undoubtedly have a role in restoring anatomy and biomechanics in smaller femoral geometries, although the surgeon has to appreciate the higher risk of stem fracture and the associated predisposing factors which may necessitate particular attention to surgical technique and planning.

Cite this article: Bone Jt Open 2021;2(6):443–456.

Patient-reported outcomes after hip and knee arthroplasty : results from a large national registry

AIMS

This study aims to describe the pre- and postoperative self-reported health and quality of life from a national cohort of patients undergoing elective total conventional hip arthroplasty (THA) and total knee arthroplasty (TKA) in Australia. For context, these data will be compared with patient-reported outcome measures (PROMs) data from other international nation-wide registries.

METHODS

Between 2018 to 2020, and nested within a nationwide arthroplasty registry, preoperative and six-month postoperative PROMs were electronically collected from patients before and after elective THA and TKA. There were 5,228 THA and 8,299 TKA preoperative procedures as well as 3,215 THA and 4,982 TKA postoperative procedures available for analysis. Validated PROMs included the EuroQol five-dimension five-level questionnaire (EQ-5D-5L; range 0 to 100; scored worst-best health), Oxford Hip/Knee Scores (OHS/OKS; range 0 to 48; scored worst-best hip/knee function) and the 12-item Hip/Knee disability and Osteoarthritis Outcome Score (HOOS-12/KOOS-12; range 0 to 100; scored best-worst hip/knee health). Additional items included preoperative expectations, patient-perceived improvement, and postoperative satisfaction. Descriptive analyses were undertaken.

RESULTS

For THA and TKA patients respectively, the patient profile was 2,850 (54.5%) and 4,684 (56.4%) female, mean age 66.8 years (SD 10.6) and 67.5 (SD 8.8), and mean BMI 29.9 kg/m2 (SD 7.7) and 32.5 kg/m2 (SD 7.0). The proportion of THA and TKA patients who reported their joint as 'much better' was 2,946 (92.6%) and 4,020 (81.6%) respectively, and the majority of patients were 'satisfied' or 'very satisfied' with their procedure (2,754 (86.5%) and 3,981 (80.8%)). There were 311 (9.7%) of THA patients and 516 (10.5%) of TKA patients who reported 'dissatisfied' or 'very dissatisfied' with their surgery.

CONCLUSION

Large improvements in pain, function, and overall health were evident following primary THA and TKA. Approximately 10% of patients reported dissatisfaction with their surgery. Future analyses will focus on factors contributing to dissatisfaction after arthroplasty. Cite this article: Bone Jt Open 2021;2(6):422-432.

Incidental findings detected on preoperative CT imaging obtained for robotic-assisted joint replacements: clinical importance and the effect on the scheduled arthroplasty

OBJECTIVE

To determine the type and frequency of incidental findings detected on preoperative computed tomography (CT) imaging obtained for robotic-assisted joint replacements and their effect on the planned arthroplasty.

MATERIALS AND METHODS

All preoperative CT examinations performed for a robotic-assisted knee or total hip arthroplasty were obtained. This resulted in 1432 examinations performed between September 2016 and February 2020 at our institution. These examinations were initially interpreted by 1 of 9 fellowship-trained musculoskeletal radiologists. Using a diagnosis search, the examination reports were then reviewed to catalog all incidental findings and further classify as significant or non-significant findings. Demographic information was obtained. In those with significant findings, a chart review was performed to record the relevant workup, outcomes, and if the planned arthroplasty was affected.

RESULTS

Incidental findings were diagnosed in 740 (51.7%) patients. Of those with incidental findings, 41 (5.5%) were considered significant. A significant finding was more likely to be detected in males (P = 0.007) and on the hip protocol CT (P = 0.014). In 8 patients, these diagnoses resulted in either delay or cancelation of the arthroplasty. A planned total hip arthroplasty was more likely to be altered as compared to a knee arthroplasty (P = 0.018).

CONCLUSION

Incidental findings are commonly detected by radiologists on preoperative CT imaging obtained for robotic-assisted joint replacement. Several were valuable findings and resulted in a delay or even cancelation of the planned arthroplasty after the detection of critical diagnoses, which if not identified may have resulted in devastating outcomes.

Surgeon practice patterns for pre-soaking ACL tendon grafts in vancomycin: a survey of the ACL study group

PURPOSE

To survey members of The ACL study group to determine the current practice patterns surrounding the technique of pre-soaking ACL grafts in vancomycin.

METHODS

A web-based questionnaire was distributed to members of the ACL Study Group. Questions included the use of vancomycin solution for graft soaking during ACL reconstruction, their protocol for soaking the graft, vancomycin concentration utilized, graft choices, and concerns with the technique.

RESULTS

Sixty-six (57%) ACL surgeons completed the survey. Approximately one-third (37.9%) of respondents currently pre-soak their ACL grafts in vancomycin prior to implantation, with 60% of these surgeons being from Europe. Seventy-six percent have adopted this practice within the past 5 years. The majority of surgeons wrap the graft in a vancomycin-soaked gauze prior to implantation (56%), soak for a variable amount of time before implantation (56%), use a concentration of 5 mg/mL (68%), and soak hamstring grafts (92%). Concerns included the mechanical properties of the graft (35%), cost of vancomycin (23%), availability (12%), and antibiotic resistance (9%).

CONCLUSION

This survey demonstrates that 37.9% of ACL study group members currently utilize vancomycin to pre-soak ACL tendon grafts as a means to decrease post-operative infection risk, with the majority of surgeons having implemented this practice within the past 5 years. The biggest concern towards using vancomycin was the mechanical properties of the graft after soaking.

LEVEL OF EVIDENCE

IV.

Online Crowdsourcing to Explore Public Perceptions of Robotic-Assisted Orthopedic Surgery

BACKGROUND

The clinical benefits of robotic-assisted technology in total joint arthroplasty are unclear, but its use is increasing. This study employed online crowdsourcing to explore public perceptions and beliefs regarding robotic-assisted orthopedic surgery.

METHODS

A 30-question survey was completed by 588 members of the public using Amazon Mechanical Turk. Participants answered questions regarding robotic-assisted orthopedic surgery, sociodemographic factors, and validated assessments of health literacy and patient engagement. Multivariable logistic regression modeling was used to determine population characteristics associated with preference for robotic technology.

RESULTS

Most respondents believe robotic-assisted surgery leads to better results (69%), fewer complications (69%), less pain (59%), and faster recovery (62%) than conventional manual methods. About half (49%) would prefer a low-volume surgeon using robotic technology to a high-volume surgeon using conventional manual methods. The 3 main concerns regarding robotic technology included lack of surgeon experience with robotic surgery, robot malfunction causing harm, and increased cost. Only half of respondents accurately understand the actual role of the robot in the operating room. Overall, 34% of participants have a clear preference for robotic-assisted surgery over a conventional manual approach. After multivariable regression analysis, Asian race, working in healthcare, early technology adoption, and prior knowledge of robotic surgery were independent predictors of preferring robotic-assisted surgery.

CONCLUSION

The public's unawareness of the dubious outcome superiority associated with robotic-assisted orthopedic surgery may contribute to misinformed decisions in some patients. Robotic-assisted technology appears to be a powerful marketing tool for surgeons and hospitals.

Implications for research and clinical use from a Rasch analysis of the HOOS-12 and KOOS-12 instruments

OBJECTIVE

To evaluate the structural validity of the 12-item Hip disability and Osteoarthritis Outcome Score (HOOS-12) and 12-item Knee injury and Osteoarthritis Outcome Score (KOOS-12) using Rasch analysis and consider psychometric implications for research and clinical use.

METHOD

Individual-level HOOS-12 and KOOS-12 data from the Australian Orthopaedic Association National Joint Replacement Registry, collected before and after primary total hip and knee replacement, were used for this analysis. Using the Rasch analytic approach, overall model fit and item fit were examined, together with potential reasons for misfit including response threshold ordering, differential item functioning, internal consistency, unidimensionality and item targeting.

RESULTS

Overall misfit to the Rasch model was evident for both instruments. A degree of item misfit was also observed, although most items demonstrated logical sequencing of response options. Only two items (hip/knee pain frequency and awareness of hip/knee problems) displayed disordered response thresholds. The pain, function, and quality of life domains of the HOOS-12 and KOOS-12 demonstrated excellent internal consistency reliability (person separation index: 0.80-0.93) and unidimensionality. A mismatch between item difficulty and person ability scores at the highest end of the HOOS-12 and KOOS-12 scales contributed to post-operative ceiling effects (mean logit for HOOS-12: 3.57; KOOS-12: 2.58; ≈0 indicates well-targeted scale).

CONCLUSION

We found evidence to support the structural validity of the three HOOS-12 and KOOS-12 domains for evaluating joint replacement outcomes. However, there may be missing content in both instruments particularly for high-functioning patients. Minor refinement of some response options may be warranted to improve item performance.

Patellar Tracking in Revision Total Knee Arthroplasty: Does Retaining a Patella From a Different Implant System Matter?

BACKGROUND

Patellar maltracking is a potential surgical complication following total knee arthroplasty (TKA) and can result in anterior knee pain, recurrent patellar dislocation, and damage to the medial patellar soft tissue stabilizers. Data remain unclear as to whether the patellar button should be revised during a revision TKA (rTKA) if changing the component implant system. Our study examines whether retaining the original patellar button during an rTKA using a different implant system affects patellar tracking.

METHODS

A retrospective cohort study of rTKA patients between August 2011 and June 2019 was performed at an urban, tertiary referral center. Patients were divided into 2 cohorts depending on whether their retained patella from their primary TKA was of the same (SIM) or different implant manufacturer (DIM) as the revision system used. Radiographic measurements were performed on preoperative and postoperative knee radiographs and differences were compared between the 2 groups. Baseline demographic data were also collected.

RESULTS

Of the 293 consecutive, aseptic rTKA cases identified, 122 underwent revision in the SIM cohort and 171 in the DIM cohort. There were no demographic differences between the groups. No statistical significance was calculated for differences in preoperative and postoperative patellar tilt or Insall-Salvati ratio between the groups. The DIM group was found to have more lateral patellar translation (-0.01 ± 6.09 vs 2.68 ± 7.61 mm, P = .001). However, when calculating differences in the magnitude of the translation (thereby removing differences due to laterality), no difference was observed (0.06 ± 3.69 vs 0.52 ± 4.95 mm, P = .394).

CONCLUSION

No clinically significant differences in patellar tracking were observed when the original patellar component was retained and a different revision implant system was used. Given the inherent risks of bone loss and fracture with patellar component revision, surgeons performing rTKA may retain the primary patella if it is well fixed and can still expect appropriate patellar tracking regardless of the revision implant system used.

LEVEL OF EVIDENCE

III, Retrospective cohort study.

Pelvic discontinuity: a challenge to overcome

Pelvic discontinuity (PD) has been a considerable challenge for the hip revision arthroplasty surgeon. However, not all PDs are the same. Some occur during primary cup insertion, resembling a fresh periprosthetic fracture that separates the superior and inferior portions of the pelvis, while others are chronic as a result of gradual acetabular bone loss due to osteolysis and/or acetabular implant loosening.In the past, ORIF, various types of cages, bone grafts and bone cement were utilized with little success. Today, the biomechanics and biology of PD as well as new diagnostic tools and especially a variety of new implants and techniques are available to hip revision surgeons. Ultraporous cups and augments, cup-cage constructs and custom triflange components have revolutionized the treatment of PD when used in various combinations with ORIF and bone grafts. For chronic PD the cup-cage construct is the most popular method of reconstruction with good medium-term results.Dislocation continues to be the leading cause of failure in all situations, followed by infection. Ultimately, surgeons today have a big enough armamentarium to select the best treatment approach. Case individualization, personal experience and improvisation are the best assets to drive treatment decisions and strategies. Cite this article: EFORT Open Rev 2021;6:459-471. DOI: 10.1302/2058-5241.6.210022.

The application of topical vancomycin powder for the prevention of surgical site infections in primary total hip and knee arthroplasty: A meta-analysis

BACKGROUND

Surgical site infections (SSIs), particularly periprosthetic joint infections (PJI), following a primary total joint arthroplasty (TJA) impose a major burden by increasing morbidity, mortality, disability rate, and health expenditure. Surgeons are increasingly using topical vancomycin powder as a preventative measure, but the effectiveness of this method has been debated in TJA. Thus, we designed a meta-analysis to compare the outcomes after primary TJA between a group treated with topical vancomycin powder and an untreated control group aiming to answer: (1) whether the application of topical vancomycin powder can reduce the infection rate after primary total joint replacement; (2) are the main types of pathogens causing SSIs after the application of topical vancomycin powder different from those of patients not using topical vancomycin?

MATERIALS AND METHODS

A meta-analysis was conducted in accordance with the PRISMA guidelines. We included retrospective cohort studies and prospective randomized controlled trials of patients who underwent primary total joint arthroplasty with and without vancomycin powder application before wound closure and reported the SSI rates. The English literature in the PubMed (MEDLINE), EMBASE, Web of Science, and the Cochrane Library databases was comprehensively searched. Literature search, data extraction, and quality assessment were conducted by 2 authors. The main outcomes were SSI and PJI rates, and the secondary outcome was the bacterial spectrum. Statistical analyses were performed with the Review Manager (RevMan) Version 5.3.

RESULTS

Six retrospective cohort studies and 3 prospective cohort studies with 4512 participants were included (2354 in vancomycin group and 2158 in the control group). In the TJA group, the vancomycin powder-treatment resulted in a significantly lower proportion of patients with SSIs (relative risk [RR]=0.40, 95% confidence interval [CI]=0.27-0.61 [p<0.001]) or PJI (RR=0.37, 95% CI=0.23-0.60 (p<0.001)). In the total hip arthroplasty group, the vancomycin powder treatment decreased the rate of SSIs and PJI by 66% (RR=0.34, 95% CI=0.15-0.78 [p=0.01]) and 74% (RR=0.26, 95% CI=0.10-0.67 (p=0.005)), respectively. In the total knee arthroplasty group, the vancomycin powder decreased the rate of SSIs and PJI by 67% (RR=0.43, 95% CI=0.26-0.70 [p<0.001]) and 66% (RR=0.44, 95% CI=0.25-0.77 [p=0.004]) respectively. Staphylococcus aureus (or methicillin-sensitiveStaphylococcus aureus) (6 in vancomycin group versus 11 in control group) was the most common pathogenic bacteria, followed by Staphylococcus epidermidis (1 in vancomycin group versus 2 in control group) and methicillin-resistant Staphylococcus aureus (2 in vancomycin group versus 4 in control group). Pseudomonas aeruginosa was the main gram-negative pathogen, with 3 cases in the control group and 1 case in the vancomycin powder-treatment group.

DISCUSSION

The local application of vancomycin powder could significantly decrease the rate of SSIs and PJI in primary TJA without modifying the spectrum of bacteria involved. We recommend topical administration of the vancomycin powder before wound closure after a full evaluation of the patients.

LEVEL OF EVIDENCE

III; meta-analysis.

Catastrophic failure and metallosis of the acetabular component in total hip arthroplasty

Background

To evaluate the clinical features and results of the revision total hip arthroplasties (THA) in patients with catastrophic failures and metallosis.

Methods

Fifteen hips of 14 patients with catastrophic failure and metallosis in hip arthroplasties were evaluated. They were followed for at least 4.2 years after the revision THA. Clinical evaluation was performed using Harris hip score. Osteolysis, loosening or presence of metallosis was evaluated with standard radiographs. Metallosis was evaluated intraoperatively according to the metallosis severity classification.

Results

The mean time from failure until revision surgery was 9.4 years. It was observed that in the primary THA, metal-on-ceramic (MoC), ceramic-on-ceramic (CoC) and metal-on-conventional polyethylene (MoCPE) bearings were used in 1, 3 and 11 hips, respectively. Grade III metallosis was observed in all patients during revision surgeries. The mean Harris hip score increased from 55 points before revision THA to 75 points at the final follow-up. In revision arthroplasty, MoCPE and CoC bearings were used in 13 and 2 hips, respectively. The femoral stem was replaced in 5 hips. All acetabular cups, except that of one hip, were revised.

Conclusions

Revisions of THAs with catastrophic failures and metallosis are quite challenging. Routine follow-up of arthroplasty patients is beneficial to examine for osteolysis, loosening, and asymmetric wear.

Retrospective Analysis of Pain Relief in Total Knee Replacement Surgeries

Background and Aims

The aim of the study is to measure the postoperative adequacy of pain relief and functional recovery after unilateral primary total knee arthroplasty or total knee replacement (TKR) with a multimodal approach.

Settings and Design

This was a retrospective observational study done in a tertiary care center.

Materials and Methods

Eighty patients aged 18-65 years (yrs) with ASA Physical Status Classes I, II, and III operated for unilateral primary TKR surgery under suitable Anaesthesia and was administered ultrasound-guided adductor canal block + periarticular infiltration (PI) from January 2018 to January 2019 were included. Thereafter, the patients visual analog scale (VAS) scores at rest, 45° knee flexion, and mobilization as well as additional analgesia given were noted after going through the records at following time points: 12 hourly for 24 h and thereafter on postoperative day 1 (POD1) and POD2. Level of block, adverse events, and functional recovery (time up and go [TUG] test, 10 s walk test) on POD1 and POD2 were also noted.

Statistical Analysis and Results

The statistical software namely SPSS 18.0 were used for the analysis of the data. The mean VAS score at 12 h was 4.33 ± 1.3 which worsened at 24 h with steady improvement over the next 2 days. Similarly, the case with a mean VAS score at 45° flexion and on mobilization showed a similar trend. At 12 h postadductor block, besides intravenous (i.v.) paracetamol, 32.6% of patients were given tramadol 50 mg i.v. whereas one patient was given a buprenorphine patch in addition to tramadol. The number of patients requiring additional tramadol and buprenorphine patch steadily increased over the next 2 days. The average time taken for the TUG test at 24 h was 30.98 ± 4.77 s, and the average time taken for the 10 s walk test at 24 h was 6.16 ± 1.10 steps with improvement in performance over the next 2 days.

Conclusion

In our study, our multimodal analgesia model did not provide satisfactory analgesia though mobilization was not hampered.

Custom TKA enables adequate realignment with minimal ligament release and grants satisfactory outcomes in knees that had prior osteotomies or extra-articular fracture sequelae

PURPOSE

To report the early clinical and radiographic outcomes of custom total knee arthroplasty (TKA) in knees that had prior osteotomies and/or extra-articular fracture sequelae.

METHODS

The authors retrospectively analysed a consecutive series of 444 knees that received custom TKA between 2016 and 2019 and identified 41 knees that had prior extra-articular events (osteotomies or fracture sequelae). Patients responded to pre- and post-operative (> 12 months) questionnaires, including Knee Society Score (KSS), Oxford Knee Score (OKS), Forgotten Joint Score (FJS) and Knee injury and Osteoarthritis Outcome Score (KOOS). Net improvements were calculated by subtracting pre- from post-operative scores. In addition to a preoperative CT scan, pre- and post-operative long-leg weight-bearing radiographs were obtained, on which the hip-knee-ankle (HKA) angle, femoral mechanical angle (FMA, between femoral mechanical axis and joint line) and tibial mechanical angle (TMA, between tibial mechanical axis and joint line) angles were measured, and alignment was planned within a 'target zone' of FMA and TMA within 85°-95° and HKA angle within 175°-183°. Agreements between preoperative, planned and post-operative angles were calculated using intra-class correlation coefficients (ICC).

RESULTS

From the initial 41 knees, 3 had incomplete post-operative data and 1 was revised for painful stiffness due to uncorrected rotational malunion, leaving 37 knees for analysis. Twenty had prior osteotomies (tibia, n = 18, femur, n = 2), 8 had isolated fractures (tibial, n = 3; femoral, n = 5), and 9 had both osteotomies and fractures. Postoperative coronal alignments were 90.4° ± 2.4° for FMA, 89.3° ± 2.6° for TMA and 179.9° ± 3.0° for HKA angle. Agreements between planned and achieved alignments were fair to excellent, and 29 (78%) knees were within the 'target zone'. At a mean follow-up of 15 ± 5 months, all clinical scores had improved significantly (p < 0.001).

CONCLUSIONS

Custom TKA granted satisfactory clinical outcomes and a low complication rate in knees that had prior osteotomies and/or extra-articular fracture sequelae. Using custom implants and strategies for coronal alignment, 29 (78%) of the 37 knees were successfully aligned within the 'target zone', and 35 (95%) of the 41 knees did not require ligament release.

LEVEL OF EVIDENCE

IV.

Pursuit of the ideal antiseptic irrigation solution in the management of periprosthetic joint infections

Irrigation and debridement in the treatment of periprosthetic joint infection (PJI) serve an integral role in the eradication of bacterial burden and subsequent re-infection rates. Identifying the optimal irrigation agent, however, remains challenging, as there is limited data on superiority. Direct comparison of different irrigation solutions remains difficult because of variability in treatment protocols. While basic science studies assist in the selection of irrigation fluids, in vitro results do not directly translate into clinical significance once implemented in vivo. Dilute povidone iodine, hydrogen peroxide, chlorhexidine gluconate, acetic acid, sodium hypochlorite, hypochlorous acid, and preformed combination solutions all have potential against a broad spectrum of PJI pathogens with their own unique advantages and disadvantages. Future clinical studies are needed to identify ideal irrigation solutions with optimal bactericidal properties and low cytotoxicity for PJI treatment.

Drug Reaction with Eosinophilia and Systemic Syndrome in Revision Arthroplasty for a Prosthetic Knee Infection: A Case Report

CASE

A 51-year-old woman underwent stage I of a 2-stage revision for a prosthetic knee infection with a vancomycin-impregnated articulating cement spacer followed by IV vancomycin and ceftriaxone. Four weeks later, she developed fevers, a diffuse cutaneous eruption, lymphadenopathy, transaminitis, and acute renal tubular necrosis before being diagnosed with drug reaction with eosinophilia and systemic syndrome (DRESS).

CONCLUSION

DRESS is a rare, potentially life-threatening adverse drug reaction with cutaneous manifestations and multiorgan involvement. Although rare, its incidence in orthopaedic patients is likely to increase with the aging population. It must be recognized early to minimize end-stage organ dysfunction and mortality.