[Risk and complication profiles of orthogeriatric patients in elective hip and knee joint replacement]

BACKGROUND

The care of geriatric patients undergoing elective orthopedic surgery is becoming increasingly more important due to demographic trends. Compared to geriatric traumatology, however, there are still no established orthogeriatric care models in Germany and therefore hardly any scientific data. The aim of this study was to describe the risk and complication profiles in older patients with elective hip and knee replacements.

METHODS

In a prospective study data were collected from orthogeriatric patients with indications for elective hip and knee replacement surgery who fulfilled defined inclusion and exclusion criteria between January 2021 and August 2023 in the orthopedic department of a German university hospital for the descriptive analysis of risk and complication profiles. In addition to a preoperative and perioperative data analysis, a follow-up was conducted 4-6 weeks and 3 months postoperatively.

RESULTS

The surgical risk profile of the patient population analyzed was characterized by advanced age (78.4 ± 4.8 years), preobesity/obesity (76%), multimorbidity (7.4 ± 3.1 comorbidities), polypharmacy (7.5 ± 3.8 medications), immobility (short physical performance battery 7.1 ± 2.6), prefrailty/frailty (87%), frequent anticoagulation (22%) and a high number of potentially inappropriate medications (64%). Complication events mainly occurred within the first 7 days postoperatively and 90% of the events within this recording period were minor complications. The overall complication rate significantly decreased in the follow-up period.

CONCLUSION

Due to the high risk and complication profiles the routine use of orthogeriatric co-management models for elective orthopedic surgery should be considered in the future.

[SOG-Special Orthopedic Geriatrics : First interim results of a randomized controlled study on integrated orthogeriatric care in elective hip and knee arthroplasty]

BACKGROUND

To date, there are no adequate care concepts for geriatric patients undergoing elective orthopaedic surgery in Germany. The Special Orthopaedic Geriatrics (SOG) study evaluates for the first time in Germany the impact of comprehensive orthogeriatric co-management on the outcome of elderly patients with elective hip and knee replacements compared to standard orthopaedic care.

METHODS

The interim analysis of the ongoing study included 174 patients; 87 patients were randomized to the intervention group and 87 to the control group. The SOG care model consists of screening, preoperative assessment with preoperative intervention, fast-track surgery and multimodal perioperative care in the orthogeriatric team. The control group received standard orthopaedic care. Mobility, complications, and patient-reported outcome measures after surgery were compared.

RESULTS

The SOG group showed a clinically relevant improvement in mobility postoperatively compared to the control group at all time points (p < 0.01). The evaluation of complications showed a significant risk reduction for minor complications (p < 0.01), as well as a clear trend towards a risk reduction for major complications. Patient-reported outcome measures showed a significant improvement in joint function and general health-related quality of life both in the SOG group and the control group.

CONCLUSION

Integrated orthogeriatric care models such as SOG could improve the care of geriatric patients in elective orthopaedic surgery in the future and, above all, make it safer.

[Fast-Track-Arthroplasty]

INTRODUCTION

Essential components of fast-track or enhanced recovery programs in arthroplasty are the optimization of interdisciplinary organizational processes, as well as pre-, intra- and postoperative procedures in everyday clinical practice. The early postoperative mobilization of patients after joint replacement surgery is of central importance, with the aim of avoiding pain and complications. This article provides a detailed overview of fast-track procedures that have already been established in many units. Furthermore, it demonstrates the clinical advantages of FastTrack for total hip arthroplasty (THA) in an evidence-based manner within the framework of a randomized study design.

MATERIAL AND METHODS

194 primary THA patients were examined after randomization into two single-blinded groups; Fast-Track (n = 98) or conventional treatment path (n = 96). Mobilization was defined as the primary outcome parameter, measured in seconds using the Timed Up and Go Test (TUG). Secondary parameters were the achievable walking distance in meters and pain using the numerical rating scale (NRS). All parameters were recorded preoperatively and daily until the sixth postoperative day.

RESULTS

No complications or revisions were recorded within the first postoperative week. The fast-track group showed significantly better TUG values and walking distance results compared to the conventional group until the sixth postoperative day (p < 0.05, respectively). There was no significant difference regarding the pain assessment (NRS) (p > 0.05).

CONCLUSION

The use of Fast-Track in hip arthroplasty can evidently improve short-term postoperative clinical outcomes. This first prospective, single-blinded, randomized controlled study showed very good clinical results with comparable pain after FastTrack THA compared to a conventional treatment path. Fast-Track concepts are highly effective in terms of early mobilization and clinical outcome-without incurring a higher risk of complications in the short term.

[Navigation and robotics-current status and future implications]

INTRODUCTION

Both navigation systems and robotics enable greater precision in the implantation of an artificial knee joint. However, they do not improve clinical outcomes. We hypothesized that although implantation of a total knee arthroplasty results in reconstruction of the alignment in the coronal plane, the variable rotational tibial and variable translational femoral and tibial component positioning lead to a change in the remaining alignment parameters of the lower extremity. However, these parameters could be determined using a navigation system or robot and could represent future implications for these systems.

METHODS

The kinematics and the position between femur and tibia before and after implantation of a total knee arthroplasty were determined using a navigation system in nine healthy knee joints of Thiel-fixed whole-body cadavers.

RESULTS

After arthroplasty, there was no change in the natural coronal alignment. In extension and the early degrees of flexion, the rotational position of the femur relative to the tibia was altered. This also led to a change in the positioning of the medial and lateral epicondyle in relation to the tibia; while both epicondyles were positioned more laterally in relation to the tibia after arthroplasty, the lateral epicondyle was significantly more lateral in relation to the tibia up to 20° of flexion.

DISCUSSION

Following arthroplasty of a knee joint using the established technique, a good reconstruction of the coronal alignment was achieved with simultaneous changes in the alignment in both the rotational and translational directions between the femur and tibia. Using navigation as well as robotics, we would be able to quantify all alignment parameters and could achieve an alignment of the components or a reconstruction of the overall alignment in all six degrees of freedom. We might also be able to achieve a clinical advantage or increase the service life even further.

[Trends in navigation-handheld systems]

Navigation-assisted surgical procedures in orthopedics and trauma surgery have become increasingly widespread over the last 20 years. In addition to applications in spinal surgery, they are primarily available for knee and hip endoprosthetics. On the one hand, computer-assisted procedures have been increasingly expanded with robotic assistance systems in recent years, and on the other hand, so-called handheld navigation systems have been developed, which enable specialized use directly in the operating field at lower acquisition costs. The aim of this overview is to describe current handheld systems and to present the respective technical principles and the available scientific results. Three handheld systems for TKA use, two for THA use and one system to support pedicle screw placement on the spine are presented.

[Injection treatment for cervical and lumbar syndromes : Special infiltration techniques]

Minimally invasive injection treatment is indicated particularly in cases of treatment-resistant, painful degenerative alterations of the cervical and lumbar spine, intervertebral disc displacement and radicular syndrome. Through the injections and the supplementation with further conservative, e.g., physical therapy and activating measures, the vicious circle of neural irritation and muscle tension and sympathetic nerve reactions can be interrupted.

Bone Mineral Density is Associated With Adverse Events but not Patient-Reported Outcomes in Total Hip and Knee Arthroplasty

BACKGROUND

Although osteoporosis is common in patients undergoing elective total hip arthroplasty (THA) and total knee arthroplasty (TKA), its impact on postoperative outcomes has been inadequately studied. The purpose of this study was to evaluate the impact of bone mineral density (BMD) on adverse events and patient-reported outcomes in THA and TKA.

METHODS

A series of 1,306 THA and 1,046 TKA patients who had received osteodensitometry were analyzed retrospectively. Rates of readmission, complication, transfusion, and patient-reported outcome were correlated with BMD. Multivariable logistic regression models were used to assess the relationship between osteoporosis and adverse events.

RESULTS

Osteoporosis patients showed higher rates of 90-day readmission (THA: 8.5% versus 4.0%, P = .02; TKA: 8.9% versus 4.4%, P = .04) and transfusion (THA: 6.8% versus 1.2%, P < .001; TKA: 5.4% versus 1.5%, P = .005). After THA, rates of complications requiring intensive care management (5.1% versus 0.7%, P < .001) and rates of medical complications (3.5% versus 0.6%, P = .001) were increased. After TKA, rates of surgical complications (2.8% versus 0.8%, P = .04) were increased. Postoperatively, osteoporosis patients improved to comparable patient-reported outcomes as patients who had normal BMD. Multivariable logistic regression analyses revealed osteoporosis as an independent risk factor for readmissions, complications, and transfusions.

CONCLUSION

Osteoporosis is a risk factor for adverse events after THA and TKA. Affected patients show similar improvement of patient-reported outcome compared to patients who have normal BMD. As osteoporosis is modifiable, a systematic screening of patients scheduled for THA or TKA should be discussed.

The impact of primary total hip and knee replacement on frailty: an observational prospective analysis

BACKGROUND

Osteoarthritis is a prevalent condition in frail older adults that requires hip or knee replacement in many patients. The aim of the study was to determine the impact of hip and knee arthroplasty on frailty.

METHODS

In this prospective short-term study, we used data from 101 participants of the ongoing Special Orthopaedic Geriatrics (SOG) trial, funded by the German Federal Joint Committee (GBA). Frailty, measured by Fried's Physical Frailty Phenotype (PFP), was assessed preoperatively, 7 days postoperatively, 4-6 weeks and 3 months after hip and knee arthroplasty. ANOVA with repeated measures and post-hoc tests for the subgroups were used for the statistical analysis.

RESULTS

Of the 101 participants, 50 were pre-frail (1-2 PFP criteria) and 51 were frail (≥ 3 PFP criteria) preoperatively. In the pre-frail group, the PFP score decreased from 1.56 ± 0.50 (median 2) preoperatively to 0.53 ± 0.73 (median 0) 3 months after surgery (p < 0.001). The PFP score in the frail cohort decreased from 3.39 ± 1.45 (median 3) preoperatively to 1.27 ± 1.14 (median 1) 3 months postoperatively (p < 0.001). While the PFP score of the pre-frail participants increased 7 days after surgery, the PFP score of the frail group decreased significantly.

CONCLUSION

Pre-frail individuals often regain robustness and patients with frailty are no longer assessed as frail after surgery. Joint replacement is an effective intervention to improve frailty in hip and knee osteoarthritis.

TRIAL REGISTRATION

This study is part of the Special Orthopaedic Geriatrics (SOG) trial, German Clinical Trials Register DRKS00024102. Registered on 19 January 2021.

Influence of bone mineral density on femoral stem subsidence after cementless THA

INTRODUCTION

Femoral stem subsidence can lead to aseptic loosening after total hip arthroplasty (THA). Low bone mineral density (BMD) is a risk factor for stem subsidence as it can affect the initial stability and osteointegration. We evaluated whether reduced bone mineral density is related to higher subsidence of the femoral stem after primary cementless THA with enhanced recovery rehabilitation.

METHODS

79 patients who had undergone primary cementless THA with enhanced recovery rehabilitation were analyzed retrospectively. Subsidence of the femoral stem was measured on standing pelvic anterior-posterior radiographs after 4-6 weeks and one year. Patient individual risk factors for stem subsidence (stem size, canal flare index, canal fill ratio, body mass index (BMI), demographic data) were correlated. Dual X-ray absorptiometry (DXA) scans were performed of the formal neck and the lumbar spine including the calculation of T-score and Z-score. Patient-reported outcome measures were evaluated 12 months postoperatively.

RESULTS

Stem subsidence appeared regardless of BMD (overall collective 2.3 ± 1.64 mm). Measure of subsidence was even higher in patients with normal BMD (2.8 ± 1.7 mm vs. 2.0 ± 1.5 mm, p = 0.05). High BMI was correlated with increased stem subsidence (p = 0.015). Subsidence had no impact on improvement of patient-related outcome measures (WOMAC, EQ-5D-5L and EQ-VAS) after THA. Patients with low BMD reported lower quality of life 12 month postoperatively compared to patients with normal BMD (EQ-5D-5L 0.82 vs. 0.91, p = 0.03).

CONCLUSION

Stable fixation of a cementless stem succeeds also in patients with reduced BMD. Regarding stem subsidence, enhanced recovery rehabilitation can be safely applied in patients with low BMD.

Influence of avascular necrosis of the femoral head on hip prosthesis integration: a radiological analysis

BACKGROUND

Avascular osteonecrosis of the femoral head (AVN) often results in total hip arthroplasty (THA). The cause for increased THA revision rates among patients with AVN is not yet fully understood.

PURPOSE

To perform a comparative radiological analysis of implant integration between patients with AVN and osteoarthritis (OA).

MATERIAL AND METHODS

After a matched pair analysis of 58 patients, 30 received THA due to OA, 28 due to AVN. X-ray images were evaluated after one week ("baseline") and on average 37.58 months postoperatively ("endline"). The prosthesis was grouped into 10 regions of interest (ROI): seven femoral and three acetabular. Incidence, width, and extent of "radiolucent lines" were measured within each zone.

RESULTS

Between baseline and endline, width and extent progressed more noticeably in all femoral and acetabular zones among patients with AVN. In femoral ROI 1, the width increased in 40% of AVN cases compared to 6.7% of OA cases. For acetabular ROI 3, the width increased in 26.7% of AVN cases compared to no perceived changes in the OA group. No signs of prosthetic loosening were found in the AVN group.

CONCLUSION

The increase of width and extent of radiolucent lines over time in patients with AVN could be a sign of lack of osteointegration. However, prosthetic loosening in absence of clinical symptoms cannot be deduced from radiological findings after medium-term postoperative follow-up. Further long-term studies are required to monitor how radiolucent lines develop in respect to long-term implant loosening. Dependent on bone quality, individually adapted reaming and broaching of the implant site are recommended.

Better early outcome with enhanced recovery total hip arthroplasty (ERAS-THA) versus conventional setup in randomized clinical trial (RCT)

INTRODUCTION

Numbers of total hip arthroplasty (THA) are steadily rising and patients expect faster mobility without pain postoperatively. The aim of enhanced recovery after Surgery (ERAS) programs in a multidisciplinary setup was to keep pace with the needs of quality and quantity of surgical THA-interventions and patients' expectations.

METHODS

194 patients undergoing THA procedures were investigated after single-blinded randomization to ERAS (98) or conventional setup group (96). Primary outcome variable was mobilization measured with the Timed Up and Go Test (TUG) in seconds. Secondary outcome variables were floor count and walking distance in meters as well as rest, mobilization and night pain on a numerous rating scale (NRS). All variables were recorded preoperatively and daily until the sixth postoperative day. To assess and compare clinical outcome and patient satisfaction, the PPP33-Score and PROMs were used.

RESULTS

No complications such as thromboembolic complications, fractures or revisions were recorded within the first week postoperatively in either study group. Compared to the conventional group, the ERAS group showed significantly better TUG (p < 0.050) and walking distance results after surgery up to the sixth, and floor count up to the third postoperative day. On the first and second postoperative day, ERAS patients showed superior results (p < 0.001) in all independent activity subitems. Regarding the evaluation of pain (NRS), PPP33 and PROMS, no significant difference was shown (p > 0.050).

CONCLUSION

This prospective single-blinded randomized controlled clinical trial was able to demonstrate excellent outcome with comparable pain after ERAS THA versus a conventional setup. Therefore, ERAS could be used in daily clinical practice.

[Injection treatment for cervical and lumbar syndromes: principles, indications and general performance]

An intensive conservative treatment that exhausts all treatment options should fundamentally be carried out before every surgical intervention in the region of the spinal column. The therapeutic measures are determined by the extent of the cervical or lumbar syndrome. As a rule, in cases of local complaints symptomatic measures with physiotherapy or digital healthcare applications are indicated. In cases of referred cervical and lumbar syndromes targeted injections can be employed. Before targeted injection treatment a detailed orthopedic clarification with respect to the intensity of local, radicular or pseudoradicular complaints must be carried out. When carrying out minimally invasive injection treatment specific prerequisites with respect to spatial, personnel and technical conditions must be fulfilled. The indications and contraindications must be strictly controlled.

[Shoulder endoprosthesis-When and which model?]

Advanced omarthritis or an irreparable lesion of the rotator cuff are indications for the implantation of a shoulder prosthesis. Several models are available and the choice of model depends on the specific pathology of the patient. Preoperative medication management must be taken into account in rheumatism patients. The correct aftercare is essential for the proper functioning of the prosthesis.

[Outcome of joint replacement in patients with underlying rheumatoid disease]

BACKGROUND

Artificial joint replacement is a meaningful treatment option for patients with advanced rheumatic degenerative joint diseases. The aim of this study was to investigate the influence of the underlying rheumatic diseases on postoperative complications and patient-reported outcome (PRO) after elective total joint replacement (TJR).

MATERIAL AND METHODS

In a retrospective analysis of 9149 patients with elective total knee or total hip arthroplasty (TKR and THR), complication rates and PRO of patients with and without rheumatic diseases (RD) were compared. Multivariate logistic regression models were used to determine whether the underlying rheumatic disease was an independent risk factor for various complications.

RESULTS

In the univariate analyses the RD patients had an increased risk of medical complications (7.1% vs. 5.2%; p = 0.028) and Clavien-Dindo grade IV complications (2.8% vs. 1.8%; p = 0.048) after TJR. This was confirmed in multivariate statistical analyses (p < 0.034). The rates for operative revisions and surgical complications were comparable (2.5% vs. 2.4%; p = 0.485). Analysis of the PRO showed a higher responder rate in patients with RD after TKR (91.9% vs. 84.5%, p = 0.039). In contrast, the responder rate in patients with RD after THR was comparable (93.4% vs. 93.2%, p = 0.584).

CONCLUSION

Despite increased postoperative complication rates, patients with underlying rheumatic diseases showed a comparable outcome 1 year after TJR. After TKR the RD patients showed even higher responder rates. Although RD patients are a vulnerable patient group, they can still benefit from joint replacement.

[Structured approach for infected prosthesis]

BACKGROUND

Endoprosthesis infections represent a major challenge for doctors and patients. Due to the increase in endoprosthesis implantation because of the increasing life expectancy, an increase in endoprosthesis infections is to be expected. In addition to infection prophylaxis, methods of infection control become highly relevant, especially in the group of geriatric and multimorbid patients. The aim is to reduce the high 1‑year mortality from prosthesis infections through a structured algorithm.

ALGORITHM FOR PROSTHESIS INFECTIONS

Prosthesis infections can basically be divided into early and late infections. According to the criteria of the International Consensus Meeting, a late infection is defined as the occurrence more than 30 days after implantation. With respect to the planned approach, the (p)TNM classification offers an orientation. In the early postoperative interval the clinical appearance is crucial as in this phase neither laboratory parameters nor an analysis of synovial fluid show a high sensitivity. It is fundamental that, apart from patients with sepsis, environment diagnostics should be initiated. If a late infection is suspected, in addition to radiological diagnostics (X-ray, skeletal scintigraphy and if necessary, computed tomography, CT), laboratory (C-reactive protein, CRP, leukocytes, blood sedimentation, and if necessary, interleukin‑6, procalcitonin) and microbiological diagnostics (arthrocentesis with synovial analysis and microbiology) are indicated; however, in addition to the arthrocentesis result, the clinical appearance is crucial in cases where an exclusion cannot be confirmed by laboratory parameters. If an infection is confirmed, the treatment depends on the spectrum of pathogens, the soft tissue situation and the comorbidities, including a multistage procedure with temporary explantation and, if necessary, implantation of an antibiotic-containing spacer is necessary. A prosthesis preservation using the debridement, antibiotics and implant retention (DAIR) regimen is only appropriate in an acute infection situation. Basically, radical surgical debridement should be carried out to reduce the pathogen load and treatment of a possible biofilm formation for both early and late infections. The subsequent antibiotic treatment (short or long interval) should be coordinated with the infectious disease specialists.

CONCLUSION

A structured approach for prosthesis infections oriented to an evidence-based algorithm provides a sufficient possibility of healing. An interdisciplinary approach involving cooperation between orthopedic and infectious disease specialists has proven to be beneficial. Surgical treatment with the aim of reducing the bacterial load by removing the biofilm with subsequent antibiotic treatment is of intrinsic importance.

Arthrosis diagnosis and treatment recommendations in clinical practice: an exploratory investigation with the generative AI model GPT-4

BACKGROUND

The spread of artificial intelligence (AI) has led to transformative advancements in diverse sectors, including healthcare. Specifically, generative writing systems have shown potential in various applications, but their effectiveness in clinical settings has been barely investigated. In this context, we evaluated the proficiency of ChatGPT-4 in diagnosing gonarthrosis and coxarthrosis and recommending appropriate treatments compared with orthopaedic specialists.

METHODS

A retrospective review was conducted using anonymized medical records of 100 patients previously diagnosed with either knee or hip arthrosis. ChatGPT-4 was employed to analyse these historical records, formulating both a diagnosis and potential treatment suggestions. Subsequently, a comparative analysis was conducted to assess the concordance between the AI's conclusions and the original clinical decisions made by the physicians.

RESULTS

In diagnostic evaluations, ChatGPT-4 consistently aligned with the conclusions previously drawn by physicians. In terms of treatment recommendations, there was an 83% agreement between the AI and orthopaedic specialists. The therapeutic concordance was verified by the calculation of a Cohen's Kappa coefficient of 0.580 (p < 0.001). This indicates a moderate-to-good level of agreement. In recommendations pertaining to surgical treatment, the AI demonstrated a sensitivity and specificity of 78% and 80%, respectively. Multivariable logistic regression demonstrated that the variables reduced quality of life (OR 49.97, p < 0.001) and start-up pain (OR 12.54, p = 0.028) have an influence on ChatGPT-4's recommendation for a surgery.

CONCLUSION

This study emphasises ChatGPT-4's notable potential in diagnosing conditions such as gonarthrosis and coxarthrosis and in aligning its treatment recommendations with those of orthopaedic specialists. However, it is crucial to acknowledge that AI tools such as ChatGPT-4 are not meant to replace the nuanced expertise and clinical judgment of seasoned orthopaedic surgeons, particularly in complex decision-making scenarios regarding treatment indications. Due to the exploratory nature of the study, further research with larger patient populations and more complex diagnoses is necessary to validate the findings and explore the broader potential of AI in healthcare.

LEVEL OF EVIDENCE

Level III evidence.

Comparison of postoperative isokinetic quadriceps and gluteal muscular strength after primary THA: is there an early benefit through enhanced recovery programs?

PURPOSE

Although total hip arthroplasty (THA) is expected to result in a postoperative loss of muscular strength, no study investigated the benefit of an enhanced-recovery-after-surgery (ERAS) concept on the hip muscles in detail. We evaluated if (1) an ERAS-concept for primary THA results in reduced loss of muscular strength five days and four weeks postoperative. We (2) compared the two groups regarding Patient-Related-Outcome-Measures (PROMs), WOMAC-index (Western-Ontario-and-McMaster-Universities-Osteoarthritis-Index), HHS (Harris-Hip-Score) and EQ-5d-3L-score.

METHODS

In a prospective, single-blinded, randomized controlled trial, we compared isokinetic muscular strength of 24 patients receiving primary THA with an enhanced recovery concept with early mobilization (n = 12, ERAS-group) and such receiving conventional THA (n = 12, non-ERAS). Isokinetic muscular strength was measured with a Biodex-Dynamometer before, as well as five days and four weeks after surgery (peak-torque, total-work, power). Furthermore, WOMAC, HHS, PROMs and EQ-5d-3L were imposed.

RESULTS

The ERAS group revealed significant higher isokinetic strength (peak-torque, total-work, power) at both time points. Both groups showed a significant pain decrease at both time points meeting very high rates of patient satisfaction resembled by good results in PROMs, WOMAC, HHS, EQ-5d. There was no significant difference in any of the scores between both groups.

CONCLUSION

We proved a significant reduced loss of muscular strength five days and four weeks after primary THA in combination with an ERAS concept. However, the reduced loss of muscular strength is not reflected by patient's functional outcome and quality of life, showing no significant differences in WOMAC, HHS, EQ-5d-3L, PROMs and NRS. Therefore, this study supports the implementation of an ERAS concept for primary THA in terms of isokinetic strength. Further studies are needed to evaluate the development of muscular strength over a long period.

The impact of elective total hip and knee arthroplasty on physical performance in orthogeriatric patients: a prospective intervention study

BACKGROUND

Osteoarthritis is a prevalent condition in older adults that leads to reduced physical function in many patients and ultimately requires hip or knee replacement. The aim of the study was to determine the impact of hip and knee arthroplasty on the physical performance of orthogeriatric patients with osteoarthritis.

METHODS

In this prospective study, we used data from 135 participants of the ongoing Special Orthopaedic Geriatrics (SOG) trial, funded by the German Federal Joint Committee (GBA). Physical function, measured by the Short Physical Performance Battery (SPPB), was assessed preoperatively, 3 and 7 days postoperatively, 4-6 weeks and 3 months after hip and knee arthroplasty. For the statistical analysis, the Friedman test and post-hoc tests were used.

RESULTS

Of the 135 participants with a mean age of 78.5 ± 4.6 years, 81 underwent total hip arthroplasty and 54 total knee arthroplasty. In the total population, SPPB improved by a median of 2 points 3 months after joint replacement (p < 0.001). In the hip replacement group, SPPB increased by a median of 2 points 3 months after surgery (p < 0.001). At 3 months postoperatively, the SPPB increased by a median of 1 point in the knee replacement group (p = 0.003).

CONCLUSION

Elective total hip and knee arthroplasty leads to a clinically meaningful improvement in physical performance in orthogeriatric patients with osteoarthritis after only a few weeks.

TRIAL REGISTRATION

This study is part of the Special Orthopaedic Geriatrics (SOG) trial, German Clinical Trials Register DRKS00024102. Registered on 19 January 2021.

No clinically significant difference in postoperative pain and side effects comparing conventional and enhanced recovery total hip arthroplasty with early mobilization

INTRODUCTION

Enhanced recovery after surgery (ERAS) leads to less morbidity, faster recovery, and, therefore, shorter hospital stays. The expected increment of primary total hip arthroplasty (THA) in the U.S. highlights the need for sufficient pain management. The favorable use of short-lasting spinal anesthesia enables early mobilization but may lead to increased opioid consumption the first 24 h (h) postoperatively.

METHODS

In a retrospective study design, we compared conventional THA with postoperative immobilization for two days (non-ERAS) and enhanced recovery THA with early mobilization (ERAS group). Data assessment took place as part of the "Quality Improvement in Postoperative Pain Treatment project" (QUIPS). Initially, 2161 patients were enrolled, resulting in 630 after performing a matched pair analysis for sex, age, ASA score (American-Society-of-Anesthesiology) and preoperative pain score. Patient-reported pain scores, objectified by a numerical rating scale (NRS), opioid consumption and side effects were evaluated 24 h postoperatively.

RESULTS

The ERAS group revealed higher activity-related pain (p = 0.002), accompanied by significantly higher opioid consumption (p < 0.001). Maximum and minimum pain as well as side effects did not show significant differences (p > 0.05).

CONCLUSION

This study is the first to analyze pain scores, opioid consumption, and side effects in a matched pair analyses at this early stage and supports the implementation of an ERAS concept for THA. Taking into consideration the early postoperative mobilization, we were not able to detect a difference regarding postoperative pain. Although opioid consumption appeared to be higher in ERAS group, occurrence of side effects ranged among comparable percentages.

[Achilles tendon pathologies]

Achilles tendon pathologies are a frequent problem in the clinical practice. A distinction must be made between insertional and noninsertional tendinopathies. In addition to intrinsic risk factors, such as diabetes mellitus, there are also extrinsic risk factors, such as overuse and running. Sonography, X‑ray imaging and magnetic resonance imaging (MRI) are established imaging methods, depending on the question. The primary treatment includes a conservative approach. First-line treatment includes administration of nonsteroidal anti-inflammatory drugs (NSAID), physical rest and the use of assistive devices. Established conservative treatment procedures include eccentric stretching, shockwave therapy and infiltration with, e.g., platelet-rich plasma. There are numerous other conservative treatment options. After exhausting the conservative treatment options, a surgical approach can be considered. The surgical procedure depends on the clinical symptoms and findings. Established procedures are minimally invasive or endoscopic procedures or even open debridement.

The Role and Efficiency of an AI-Powered Software in the Evaluation of Lower Limb Radiographs before and after Total Knee Arthroplasty

The rapid evolution of artificial intelligence (AI) in medical imaging analysis has significantly impacted musculoskeletal radiology, offering enhanced accuracy and speed in radiograph evaluations. The potential of AI in clinical settings, however, remains underexplored. This research investigates the efficiency of a commercial AI tool in analyzing radiographs of patients who have undergone total knee arthroplasty. The study retrospectively analyzed 200 radiographs from 100 patients, comparing AI software measurements to expert assessments. Assessed parameters included axial alignments (MAD, AMA), femoral and tibial angles (mLPFA, mLDFA, mMPTA, mLDTA), and other key measurements including JLCA, HKA, and Mikulicz line. The tool demonstrated good to excellent agreement with expert metrics (ICC = 0.78-1.00), analyzed radiographs twice as fast (p < 0.001), yet struggled with accuracy for the JLCA (ICC = 0.79, 95% CI = 0.72-0.84), the Mikulicz line (ICC = 0.78, 95% CI = 0.32-0.90), and if patients had a body mass index higher than 30 kg/m2 (p < 0.001). It also failed to analyze 45 (22.5%) radiographs, potentially due to image overlay or unique patient characteristics. These findings underscore the AI software's potential in musculoskeletal radiology but also highlight the necessity for further development for effective utilization in diverse clinical scenarios. Subsequent studies should explore the integration of AI tools in routine clinical practice and their impact on patient care.

Comparison of two joint-preserving treatments for osteonecrosis of the femoral head: core decompression and core decompression with additional cancellous bone grafting

OBJECTIVE

Femoral head necrosis (FHN) affects mostly young and active people. The most common operative therapy is core decompression (CD) with optional cancellous bone grafting (CBG). Because little information is available on the long-term results of these procedures, we investigated the effectiveness of CD and CD + CBG in patients with ARCO stage II FHN in terms of postoperative pain, range of motion, patient-reported outcome measures (Harris Hip Score, Hip Disability and Osteoarthritis Outcome Score, EuroQol 5D, and Short Form 36 Questionnaire), and disease progression.

METHODS

We retrospectively compared 11 patients treated with CD alone 48.0 months (range, 26.3-68.5 months) postoperatively versus 11 patients treated with CD + CBG 69.2 months (range, 38.0-92.9 months) postoperatively. All patients were assessed according to a routine clinical protocol involving a clinical examination, questionnaires, and radiological imaging (X-ray and magnetic resonance imaging).

RESULTS

The clinical and radiological results showed no significant differences between the two groups. Both interventions demonstrated equal results according to clinical scores.

CONCLUSIONS

Our data may encourage application of the less invasive technique of CD alone without CBG, which is more surgically demanding. Further prospective studies with longer follow-up are necessary to clarify the risk factors for therapy failure.

No Success without Effort: Follow-Up at Six Years after Implementing a Benchmarking and Feedback Concept for Postoperative Pain after Total Hip Arthroplasty

BACKGROUND

Total hip arthroplasty (THA) is still ranked among the operations with the highest postoperative pain scores. Uncontrolled postsurgical pain leads to prolongated hospital stays, causes more frequent adverse reactions and can induce chronical pain syndromes. In 2014, we implemented a standardized, multidisciplinary pain management concept with continuous benchmarking at our tertiary referral center by using the "Quality Improvement in Postoperative Pain Management" (QUIPS) program with excellent results over a period of two years. The initial study ended in 2016 and we aimed to evaluate if it was possible to obtain the excellent short-term results over a period of six years without any extra effort within the daily clinical routine.

MATERIALS AND METHODS

In a retrospective study design, we compared postoperative pain, side effects and functional outcome after primary THA for 2015 and 2021, using validated questionnaires from the QUIPS project. In contrast to the implementation of the pain management concept in 2014, the weekly meetings of the multidisciplinary health care team and special education for nurses were stopped in 2021. Data assessment was performed by an independent pain nurse who was not involved in pain management.

RESULTS

Altogether, 491 patients received primary THA in 2015 and 2021 at our tertiary referral center. Collected data revealed significantly worse maximum and activity-related pain (both p < 0.001) in combination with significantly higher opioid consumption in comparison to implementation in 2015. Though the patients reported to be less involved in pain management (p < 0.001), the worse pain scores were not reflected by patient satisfaction which remained high. While the participation rate in this benchmarking program dropped, we still fell behind in terms of maximum and activity-related pain in comparison to 24 clinics.

CONCLUSION

Significantly worse pain scores in combination with higher opioid usage and a lower hospital participation rate resemble a reduced awareness in postoperative pain management. The significantly lower patient participation in pain management is in line with the worse pain scores and indirectly highlights the need for special education in pain management. The fact patient satisfaction appeared to remain high and did not differ significantly from 2015, as well as the fact we still achieved an acceptable ranking in comparison to other clinics, highlight the value of the implemented multidisciplinary pain management concept.

Preoperative Decolonization Appears to Reduce the Risk of Infection in High-Risk Groups Undergoing Total Hip Arthroplasty

BACKGROUND

Periprosthetic infections represent a major challenge for doctors and patients. The aim of this study was therefore to determine whether the risk of infection can be positively influenced by preoperative decolonization of the skin and mucous membranes.

METHODS

In a retrospective analysis of 3082 patients who had undergone THA between 2014 and 2020, preoperative decolonization with octenidine dihydrochlorid was performed in the intervention group. In an interval of 30 days, soft tissue and prosthesis infections were detected, and an evaluation between the study groups was made by using a bilateral t-test regarding the presence of an early infection. The study groups were identical with regard to the ASA score, comorbidities, and risk factors.

RESULTS

Patients treated preoperatively with the octenidine dihydrochloride protocol showed lower early infection rates. In the group of intermediate- and high-risk patients (ASA 3 and higher), there was generally a significantly increased risk. The risk of wound or joint infection within 30 days was 1.99% higher for patients with ASA 3 or higher than for patients with standard care (4.11% [13/316] vs. 2.02% [10/494]; p = 0.08, relative risk 2.03). Preoperative decolonization shows no effect on the risk of infection that increases with age, and a gender-specific effect could not be detected. Looking at the body mass index, it could be shown that sacropenia or obesity leads to increased infection rates. Preoperative decolonization led to lower infection rates in percentage terms, which, however, did not prove to be significant (BMI < 20 1.98% [5/252] vs. 1.31% [5/382], relative risk 1.43, BMI > 30 2.58% [5/194] vs. 1.20% [4/334], relative risk 2.15). In the spectrum of patients with diabetes, it could be shown that preoperative decolonization leads to a significantly lower risk of infection (infections without protocol 18.3% (15/82), infections with protocol 8.50% (13/153), relative risk 2.15, p = 0.04.

CONCLUSION

Preoperative decolonization appears to show a benefit, especially for the high-risk groups, despite the fact that in this patient group there is a high potential for resulting complications.

Isokinetic knee muscle strength comparison after enhanced recovery after surgery (ERAS) versus conventional setup in total knee arthroplasty (TKA): a single blinded prospective randomized study

PURPOSE

Total knee arthroplasty (TKA) combined with the concept of enhanced recovery is of continued worldwide interest, as it is reported to improve early functional outcome and treatment quality without increasing complications. The aim of the study was to investigate isokinetic knee muscle strength after cemented TKA in combination with an enhanced recovery after surgery (ERAS) compared to a conventional setup.

METHODS

In the single blinded prospective randomized study, 52 patients underwent navigated primary cemented TKA within an ERAS (n = 30) or a conventional setup (n = 22). Preoperatively, five days and four weeks after surgery isokinetic knee muscle strength with BIODEX-type measuring device (peak torque in Nm, work in Joules and power in Watt) and subjective patient-related outcome measures (PROMs) were investigated.

RESULTS

The ERAS group showed significantly better outcomes in knee flexion at 180°/s (peak torque (Nm) p = 0.047, work (J) p = 0.040 and power (W) p = 0.016) 5 days postoperatively. The isokinetic measuring at knee extension 60°/s and 180°/s demonstrated no significant difference. The PROMs showed that patients were satisfied with the postoperative results in both groups. After 4 weeks, there was no longer a significant difference in isokinetic measuring at knee extension and flexion between the ERAS and conventional group.

CONCLUSIONS

TKA with the concept of ERAS improves excellent isokinetic outcome and patient satisfaction. The isokinetic muscle strength measurement can help patients and surgeons to modify expectations and improve patient satisfaction.

[Update: endoprosthetics on the ankle joint]

The ankle joint has to bear the entire body weight on a relatively small joint surface. Incongruities, instabilities and deformities lead to painful arthrosis and considerable restrictions in everyday life. For many years, arthrodesis has proven to be the gold standard for end stage arthrosis; however, considering modern endoprostheses for the ankle joint it is no longer appropriate to offer only arthrodesis. The very good results of the 3rd generation 3‑component prostheses and the 4th generation 2‑component prostheses show how much the surgical treatment options for the ankle joint are currently changing. The simplified implantation techniques enable access to arthroplasty of the ankle joint for a broader spectrum of surgeons and explain the increasing implantation rates in recent years. Decisive for postoperative success are correct planning with knowledge of the leg axes and foot position, correct patient selection and exact surgical placement of the components.

[Work-related sedentary behavior]

Background

Sedentary behavior is associated with an increased risk of chronic diseases, such as metabolic syndrome and type 2 diabetes and all-cause mortality. Occupational sitting time contributes to large amounts of daily sedentary behavior, especially in office workers.

Objective

This study investigated the amount of time spent in sedentary behavior during different tasks at work and while commuting of administrative personnel of a university hospital in Germany.

Material and methods

A cross-sectional questionnaire-based study of administrative employees at the University Hospital Regensburg, Germany was carried out to assess work-related sedentary behavior. Descriptive and exploratory statistical analyses were performed.

Results

The study population consisted of 159 participants (54.1% women, 51.6% older than 40 years), which corresponds to a response rate of 26%. The median daily sitting time in the office was 7.0 h (interquartile range, IQR 6.0-7.5 h) and mostly occurred during computer work (57.3%), telephone calls (13.2%) and meetings (11.7%). Median standing time at work was 0.8 h (IQR 0.3-1.4 h). Administrative staff spent a median of 0.7 h (IQR 0.3-1.0 h) per day sedentary while commuting, with 67.3% of respondents commuting by car, motorbike or scooter. The participants were of the opinion that sitting for long uninterrupted periods had negative (69.6%) or relatively negative (29.7%) effects on health.

Conclusion

Administrative staff in hospitals spend large amounts of the daily working time with sedentary behavior. Interventions that enable working both in sitting and standing positions can lead to reduced work-related sitting time and thereby could improve occupational and, in a broader sense, public health.

Total Knee Arthroplasty Violates the Law of Burmester-A Biomechanical Investigation

BACKGROUND

Kinematic patterns of knees after total knee arthroplasty (TKA) are different from those of healthy knees. We hypothesised that these changes cause a relevant shift in the medial and lateral epicondyles and, consequently, the insertion sites of the collateral ligaments. Any alterations, however, violate the law of Burmester, which states a close relation between the course of the collateral and cruciate ligaments, and the articular surfaces.

METHODS

Ten healthy knees of whole body cadavers were investigated. The positions of the medial and lateral epicondyles in relation to the tibia were compared before and after cruciate retaining fixed bearing TKA between 0 and 90° of flexion using a navigational device.

RESULTS

After TKA, the medial and lateral epicondyles significantly shifted laterally (~3-5mm) between 0° and 40° of flexion. Additionally, the lateral epicondyle was located significantly more dorsal (~3-5mm) during 0° and 20° of flexion and significantly shifted proximally (~2.5-3mm) between 0° and 30° of flexion.

CONCLUSIONS

By changing the epicondylar positions relative to the articular surfaces, the law of Burmester is violated in the present study setting. This might explain the impairment in motion, instability, or mid-flexion instability and the persistent pain in the knees after TKA.

Special orthopaedic geriatrics (SOG) - a new multiprofessional care model for elderly patients in elective orthopaedic surgery: a study protocol for a prospective randomized controlled trial of a multimodal intervention in frail patients with hip and knee replacement

BACKGROUND

Due to demographic change, the number of older people in Germany and worldwide will continue to rise in the coming decades. As a result, the number of elderly and frail patients undergoing total hip and knee arthroplasty is projected to increase significantly in the coming years. In order to reduce risk of complications and improve postoperative outcome, it can be beneficial to optimally prepare geriatric patients before orthopaedic surgery and to provide perioperative care by a multiprofessional orthogeriatric team. The aim of this comprehensive interventional study is to assess wether multimorbid patients can benefit from the new care model of special orthopaedic geriatrics (SOG) in elective total hip and knee arthroplasty.

METHODS

The SOG study is a registered, monocentric, prospective, randomized controlled trial (RCT) funded by the German Federal Joint Committee (GBA). This parallel group RCT with a total of 310 patients is intended to investigate the specially developed multimodal care model for orthogeriatric patients with total hip and knee arthroplasty (intervention group), which already begins preoperatively, in comparison to the usual orthopaedic care without orthogeriatric co-management (control group). Patients ≥70 years of age with multimorbidity or generally patients ≥80 years of age due to increased vulnerability with indication for elective primary total hip and knee arthroplasty can be included in the study. Exclusion criteria are age < 70 years, previous bony surgery or tumor in the area of the joint to be treated, infection and increased need for care (care level ≥ 4). The primary outcome is mobility measured by the Short Physical Performance Battery (SPPB). Secondary outcomes are morbidity, mortality, postoperative complications, delirium, cognition, mood, frailty, (instrumental) activities of daily living, malnutrition, pain, polypharmacy, and patient reported outcome measures. Tertiary outcomes are length of hospital stay, readmission rate, reoperation rate, transfusion rate, and time to rehabilitation. The study data will be collected preoperative, postoperative day 1 to 7, 4 to 6 weeks and 3 months after surgery.

DISCUSSION

Studies have shown that orthogeriatric co-management models in the treatment of hip fractures lead to significantly reduced morbidity and mortality rates. However, there are hardly any data available on the elective orthopaedic care of geriatric patients, especially in total hip and knee arthroplasty. In contrast to the care of trauma patients, optimal preoperative intervention is usually possible.

TRIAL REGISTRATION

German Clinical Trials Register DRKS00024102. Registered on 19 January 2021.

Pain Course after Total Knee Arthroplasty within a Standardized Pain Management Concept: A Prospective Observational Study

BACKGROUND

Joint replacement surgeries have been known to be some of the most painful surgical procedures. Therefore, the options for postoperative pain management are of great importance for patients undergoing total knee arthroplasty (TKA). Despite successful surgery, up to 30% of the patients are not satisfied after the operation. The aim of this study is to assess pain development within the first 4 weeks after TKA in order to gain a better understanding and detect possible influencing factors.

METHODS

A total of 103 patients were included in this prospective cohort study. Postoperative pain was indicated using a numeric rating scale (NRS). Furthermore, demographic data and perioperative parameters were correlated with the reported postoperative pain.

RESULTS

The evaluation of postoperative pain scores showed a constant decrease in the first postoperative week (mean NRS score of 5.8 on day 1 to a mean NRS score of 4.6 on day 8). On day 9, the pain increased again. Thereafter, a continuous decrease in pain intensity from day 10 on was noted (continuous to a mean NRS score of 3.0 on day 29). A significant association was found between postoperative pain intensity and gender, body mass index (BMI), and preoperative leg axis.

CONCLUSIONS

The increasing pain score after the first postoperative week is most likely due to more intensive mobilization and physiotherapy in the rehabilitation department. Patients that were female, had a low BMI, and a preoperative valgus leg axis showed a significantly higher postoperative pain scores. Pain management should consider these results in the future to improve patient satisfaction in the postoperative course after TKA.

[Hallux saltans-rare diagnosis, often overlooked]

Hallux saltans is similar to digitus saltans and produces a spontaneous "snapping" of the big toe. This results in a constriction of the flexor hallucis longus tendon within the osteofibrous retromalleolar canal. The diagnosis was first described in 1940, and only a few case reports exist. We present the diagnosis and the treatment of a patient and give a review of the literature.

[Preoperative screening for risk factors]

The demographic change and continuously improving healthcare lead to increasing numbers of older, comorbid patients in elective orthopedic surgery. Perioperative risk assessment is crucial for patient counseling and preoperative planning. Risk factors, such as heart failure, chronic obstructive pulmonary disease, peripheral arterial occlusive disease, anemia, malnutrition, obesity, smoking and insufficiently controlled diabetes mellitus are common in patients undergoing elective orthopedic surgery. A thorough and early screening not only enables the individual assessment of the risk profile but in an elective setting also enables the chance for modification of certain risk factors in order to reduce the individual perioperative risk. Meanwhile, recommendations regarding risk stratification and adjustment of modifiable risk factors are included in national guidelines on the indications for elective total hip arthroplasty.

In vivo knee kinematics of an innovative prosthesis design

Up to 20% of patients after total knee arthroplasty (TKA) are not satisfied with the result. Several designs of new implants try to rebuild natural knee kinematics. We hypothesized that an innovative implant design leads to better results concerning femoral rollback compared to an established implant design. For this pilot study, 21 patients were examined during TKA, receiving either an innovative (ATTUNE^TM Knee System (DePuy Inc.), n = 10) or an established (PFC^TM (DePuy Inc.), n = 11) knee system. All patients underwent computer navigation. Knee kinematics was assessed after implantation. Outcome measure was anterior–posterior translation between femur and tibia. We were able to demonstrate a significantly higher femoral rollback in the innovative implant group (p < 0.001). The mean rollback of the innovative system was 11.00 mm (95%-confidence interval [CI], 10.77–11.24), of the established system 8.12 mm (95%-CI, 7.84–8.42). This study revealed a significantly increased lateral as well as medial femoral rollback of knees with the innovative prosthesis design. Our intraoperative finding needs to be confirmed using fluoroscopic or radiographic three-dimensional matching under full-weight-bearing conditions after complete recovery from surgery.

[Outpatient care through cross-sector prehabilitation and rehabilitation concepts in outpatient hip and knee arthroplasty]

Kein noch so flammender Appell eines Gesundheitspolitikers hat alle Versorgungsstrukturen unseres Gesundheitssystems so zur Überprüfung eigener Effizienz und Einsparpotenziale gezwungen, wie das SARS-CoV‑2. Fast-Track-Chirurgie, lange vor der aktuellen Pandemie entwickelt, kann auch unter Einbindung verzahnter Versorgungsstrukturen ein unverzichtbares Element moderner Krankenhausroutinen werden. Durch deutlich kürzere Krankenhausverweildauern, sinkende Komplikationsraten sowie durch zusätzliche Stärkung der Eigenkompetenz und Motivation der betroffenen Patientinnen und Patienten, kann die Patientenzufriedenheit und das klinische Outcome verbessert werden. Krankenhauspersonal könnte entlastet und Gesamtkosten, auch durch Einbindung externer Prähabilitationszentren, gespart werden. Es gilt nun, weiter Standards zum Aufbau und zur Umsetzung entsprechend abgestimmter Prähabilitations- und Rehabilitationskonzepte bei geplanter endoprothetischer Versorgung von Hüft- und Kniegelenken zu entwickeln und idealerweise gleichzeitig Ressourcen durch regionale Vernetzung zu sparen.

[Day-case outpatient endoprosthetics-"Ultra-Fast-Track"]

Fast-track procedures are common in general surgery today. In our European neighbour countries and in the USA, one-day-surgery for knee and hip replacement is gaining popularity. However, it is of great importance that a detailed concept for prehabilitation with a sufficient training program and targeted instructions regarding behavioral measures are established to allow a safe outpatient procedure. Where fast-track programs are established, one-day surgery with minimally invasive operative procedures for hip and knee arthroplasty is the consequent next step.

Kinematic pelvic tilt during gait alters functional cup position in total hip arthroplasty

Static pelvic tilt impacts functional cup position in total hip arthroplasty (THA). In the current study we investigated the effect of kinematic pelvic changes on cup position. In the course of a prospective controlled trial postoperative 3D-computed tomography (CT) and gait analysis before and 6 and 12 months after THA were obtained in 60 patients. Kinematic pelvic motion during gait was measured using Anybody Modeling System. By fusion with 3D-CT, the impact of kinematic pelvic tilt alterations on cup anteversion and inclination was calculated. Furthermore, risk factors correlating with high pelvic mobility were evaluated. During gait a high pelvic range of motion up to 15.6° exceeding 5° in 61.7% (37/60) of patients before THA was found. After surgery, the pelvis tilted posteriorly by a mean of 4.0 ± 6.6° (p < .001). The pelvic anteflexion led to a mean decrease of -1.9 ± 2.2° (p < .001) for cup inclination and -15.1 ± 6.1° (p < .001) for anteversion in relation to the anterior pelvic plane (APP). Kinematic pelvic changes resulted in a further change up to 2.3° for inclination and up to 12.3° for anteversion. In relation to the preoperative situation differences in postoperative cup position ranged from -4.4 to 4.6° for inclination and from -7.8 to 17.9° for anteversion, respectively. Female sex (p < .001) and normal body weight (p < .001) correlated with high alterations in pelvic tilt. Kinematic pelvic changes highly impact cup anteversion in THA. Surgeons using the APP as reference should aim for a higher anteversion of about 15° due to the functional anteflexion of the pelvis during gait.

Animal experimental investigation on the efficacy of antibiotic therapy with linezolid, vancomycin, cotrimoxazole, and rifampin in treatment of periprosthetic knee joint infections by MRSA

Aims

Periprosthetic joint infections (PJIs) are rare, but represent a great burden for the patient. In addition, the incidence of methicillin-resistant Staphylococcus aureus (MRSA) is increasing. The aim of this rat experiment was therefore to compare the antibiotics commonly used in the treatment of PJIs caused by MRSA.

Methods

For this purpose, sterilized steel implants were implanted into the femur of 77 rats. The metal devices were inoculated with suspensions of two different MRSA strains. The animals were divided into groups and treated with vancomycin, linezolid, cotrimoxazole, or rifampin as monotherapy, or with combination of antibiotics over a period of 14 days. After a two-day antibiotic-free interval, the implant was explanted, and bone, muscle, and periarticular tissue were microbiologically analyzed.

Results

Vancomycin and linezolid were able to significantly (p < 0.05) reduce the MRSA bacterial count at implants. No significant effect was found at the bone. Rifampin was the only monotherapy that significantly reduced the bacterial count on implant and bone. The combination with vancomycin or linezolid showed significant efficacy. Treatment with cotrimoxazole alone did not achieve a significant bacterial count reduction. The combination of linezolid plus rifampin was significantly more effective on implant and bone than the control group in both trials.

Conclusion

Although rifampicin is effective as a monotherapy, it should not be used because of the high rate of resistance development. Our animal experiments showed the great importance of combination antibiotic therapies. In the future, investigations with higher case numbers, varied bacterial concentrations, and changes in individual drug dosages will be necessary to be able to draw an exact comparison, possibly within a clinical trial.

Cite this article: Bone Joint Res 2022;11(3):143–151.

[Surgical treatment of focal cartilage defects in the knee : Indications, techniques, modifications and results]

The treatment strategies for focal cartilage damage in the knee are multifarious. For established procedures, such as microfracturing (MFX), autologous matrix-induced chondrogenesis (AMIC), osteochondral transplantation (OCT) and autologous chondrocyte transplantation (ACT), well-founded, partly comparative long-term studies and overlapping size-dependent differential indications are available. Innovative cell sources, the utilization of biological scaffolds as well as biologic agents and various combinations, have recently become the focus of scientific attention; however, high regulatory demands are restricting their use in Germany. The success of every procedure is dependent on the appropriate indications, the treatment of comorbidities, such as axis deviations or ligamentous instability, the surgeon's experience and an adequate follow-up treatment.

[Delirium-an interdisciplinary challenge]

BACKGROUND

Delirium is a common and potentially life-threatening disease that often poses major problems for hospitals in terms of care. It mainly affects older patients and is multifactorial, especially in older people. Permanent functional and cognitive impairments after delirium are not uncommon in geriatric patients.

DIAGNOSTIC

Often, delirious syndromes are not recognized or are misinterpreted. This is especially the case with the hypoactive form of delirium. Various screening and test procedures are available for the detection of delirium, the routine use of which is essential.

TREATMENT

In many cases, delirium can be avoided with suitable preventive measures. Above all, nondrug prevention strategies and multidimensional approaches play an important role here. For the drug treatment of delirium in geriatric patients, low-potency, classic and atypical neuroleptics, as well as dexmedetomidine for severe courses are recommended.

[Risk management in orthopedic surgery : Stratification and adjustment of patient-individual risk factors]

Preoperative identification of patients at risk of postoperative complications enables better patient education and surgical planning for the orthopedic surgeon. In addition to demographic and intervention-specific factors, a variety of instruments are available for individual risk assessment. The concept of frailty seems to be promising to identify patients at risk. Modifiable risk factors such as malnutrition, anemia, obesity, smoking, and insufficiently controlled diabetes mellitus are common in elective orthopedic patients. With the use of screening protocols, modifiable risk factors can be identified and optimized preoperatively in order to reduce the individual risk of complications. Recommendations regarding preoperative risk stratification and modification prior to elective hip replacement have meanwhile been incorporated in national guidelines.

Medial Open Wedge High tibial Osteotomy (MOWHTO) does not relevantly alter patellar kinematics: a cadaveric study

PURPOSE

The purpose of this study was to quantify the influence of medial open wedge high tibial osteotomy on patellar kinematics using optical computer navigation, as anterior knee pain infrequently occurs postoperatively and the reason is still being unknown.

METHODS

Ten medial open wedge high tibial osteotomies at supratuberosity level in 5 full body specimens were performed. The effect of the surgical procedure on patellar kinematics, measured at 5 and 10 degrees of leg alignment correction angle, was analyzed and compared to native patellar kinematics during passive motion-regarding patella shift, tilt, epicondylar distance and rotation. Linear mixed models were used for statistical analysis, a two-sided p value of ≤ 0.05 was considered statistically significant.

RESULTS

Tilt behavior, medial shift and epicondylar distance did not show a significant difference regarding natural patellar kinematics at both osteotomy levels. Both osteotomy correction angles showed a significant less external rotation of the patella (p < 0.001, respectively) compared to natural kinematics.

CONCLUSIONS

Except less external rotation of the patella, medial open wedge high tibial osteotomy does not seem to relevantly alter patellar alignment during passive motion. Future clinical studies have to prove the effect of MOWHTO on patellar kinematics measured in this experimental setup, especially regarding its influence on anterior knee pain.

Differences in femoral component subsidence rate after THA using an uncemented collarless femoral stem: full weight-bearing with an enhanced recovery rehabilitation versus partial weight-bearing

BACKGROUND

Femoral component subsidence is a known risk factor for early failure of total hip arthroplasty (THA) using cementless stems. The aim of the study was to compare an enhanced recovery concept with early full weight-bearing rehabilitation and partial weight-bearing on stem subsidence. In addition, the influence of patient-related and anatomical risk factors on subsidence shall be assessed.

METHODS

One hundred and fourteen patients underwent primary cementless THA and were retrospectively analyzed. Sixty-three patients had an enhanced recovery rehabilitation with early full weight-bearing and 51 patients had rehabilitation with partial weight-bearing (20 kg) for 6 weeks. Postoperative subsidence was analyzed on standing pelvic anterior-posterior radiographs after 4 weeks and 1 year. Subsidence was measured in mm. Anatomical and prosthetic risk factors (stem size, canal flare index, canal fill ratio as well as BMI and demographic data) were correlated.

RESULTS

Femoral stem subsidence rate was significantly higher for the group with an enhanced recovery concept compared to the group with partial weight-bearing at the first radiological follow up after 4 weeks [2.54 mm (SD ± 1.86) vs. 1.55 mm (SD ± 1.80)] and the second radiological follow up after 1 year [3.43 mm (SD ± 2.24) vs. 1.94 (SD ± 2.16)] (p < 0.001, respectively). Stem angulation > 3° had a significant influence on subsidence. Canal flare index and canal fill ratio showed no significant correlation with subsidence as well as BMI and age.

CONCLUSION

In the present study, cementless stem subsidence was significantly higher in the group with enhanced recovery rehabilitation compared to partial weight-bearing. Small absolute values and differences were demonstrated and therefore possibly below clinical relevance. Anatomical radiological parameters and anthropometric data did not appear to be risk factors for stem subsidence.

A novel radiological classification for displaced os coccyx: the Benditz-König classification

BACKGROUND

Treatment of coccygodynia is still a challenging entity. Clear surgical selection criteria are still lacking. The aim of the investigation was to establish a novel radiological classification for surgical decision-making in coccygodynia cases.

MATERIAL AND METHODS

Retrospective analysis of standing and sitting X-rays of coccygodynia patients referred to a single centre from 2018 to 2020. The sacro-coccygeal angle (SCA), the intra-coccygeal angle (ICA) and the difference of the intervertebral disc height (∆IDH) were measured. All coccyges were distributed in subtypes and correlated with the patients' treatment.

RESULTS

In total, 138 patients (female/male: 103/35) with a mean age of 45.6 ± 15.4 years were included in the study. In total, 49 patients underwent coccygectomy. Four different subtypes of displaced coccyges were identified: Type I with a non-segmented coccyx, anterior pivot, increased SCA and ICA from standing to sitting, ∆IDH = 1.0 ± 1.5 mm. Type II with a multisegmented coccyx, anterior pivot, increased SCA and ICA standing/sitting, ∆IDH = 1.1 ± 1.6 mm. Type III showed a posterior pivoted coccyx, negative SCA and ICA, ∆IDH = 0.6 ± 1.6 mm. Type IV is characterized by an anterior-posterior dissociation of the tail bone with a positive SCA, and the ICA shifted from a posterior to an anterior orientation. ∆IDH was - 0.6 ± 1.8 mm.

CONCLUSION

The presented radiological classification could help to facilitate the surgical decision-making for patients with displaced os coccyx. In addition, lateral and sitting X-rays were easy to perform and did not need unnecessary ionizing radiation like in CT scans and were more cost-effective than MRI investigations. The subtypes III and especially IV were more likely leading to surgery.

Postoperative delirium is a risk factor for complications and poor outcome after total hip and knee arthroplasty

Background and purpose - Improving health care and demographic change have resulted in a steady increase in geriatric patients undergoing total hip (THA) and knee (TKA) arthroplasty. Postoperative delirium (POD) is a frequent and severe complication after major surgery. Therefore, we analyzed the impact of POD on outcome after THA and TKA.Patients and methods - In a consecutive series of 10,140 patients who had undergone elective THA or TKA between 2011 and 2020, rates of reoperation within 90 days, readmission within 90 days, complications, and responder rate as defined by the OMERACT-OARSI criteria were compared between patients with and without POD. Multivariable logistic regression models were used to assess the relationship between POD and other postoperative complications.Results - Patients with POD showed higher rates of reoperation (12% vs. 5%), readmission (15% vs. 5%), surgical complications (7% vs. 2%), non-surgical complications (8% vs. 4%), Clavien-Dindo IV° complications (10% vs. 2%) and transfusion (14% vs. 2%). POD led to lower responder rate (76% vs. 87%) 1 year after total joint replacement. All previous comparisons statistically significant. Multivariable logistic regression analyses revealed POD as an independent risk factor for reoperation (OR = 2; CI 1-3), readmission (OR = 2; CI 2-4) and Clavien-Dindo IV° complications (OR = 3; CI 2-5).Interpretation - POD is a serious problem in elective joint replacement. Affected patients suffer more complications and show poor patient-reported outcome 1 year postoperatively. Systematic prevention strategies and standardized therapy protocols are mandatory to avoid burden to patients and healthcare providers.

[Surgical treatment of focal cartilage defects in the knee : Indications, techniques, modifications and results]

The treatment strategies for focal cartilage damage in the knee are multifarious. For established procedures, such as microfracturing (MFX), autologous matrix-induced chondrogenesis (AMIC), osteochondral transplantation (OCT) and autologous chondrocyte transplantation (ACT), well-founded, partly comparative long-term studies and overlapping size-dependent differential indications are available. Innovative cell sources, the utilization of biological scaffolds as well as biologic agents and various combinations, have recently become the focus of scientific attention; however, high regulatory demands are restricting their use in Germany. The success of every procedure is dependent on the appropriate indications, the treatment of comorbidities, such as axis deviations or ligamentous instability, the surgeon's experience and an adequate follow-up treatment.