Three-dimensional acetabular reorientation during periacetabular osteotomy: an intraoperative navigation method using an external fixator for periacetabular osteotomy.

INTRODUCTION: Bernese periacetabular osteotomy (PAO) is an effective procedure for treating acetabular dysplasia. However, limited visual control of the acetabular position during surgery may result in under- or overcorrection or changes in acetabular version resulting in residual dysplasia or femoroacetabular impingement. Thus, we wanted to develop a simple and straightforward navigation method that provides information about acetabular correction in all three planes during surgery. METHOD: Intraoperatively, acetabular coordinates are shown in coronal, sagittal, and transverse plane by two perpendicular tubes of an external fixator mounted onto a third tube that is fixed to the mobilized acetabular fragment with two Schanz screws. The application and fixation of the external fixator on the pelvis are demonstrated in this article. We used this analog navigation method on 27 PAOs, where we mainly performed a lateral rotational correction. The pre- and postoperative radiographs of these 27 hips were analyzed regarding the radiological hip parameters, taking into account the pelvic tilt. RESULTS: The mean preoperative lateral center edge angle (LCEA) of the 27 PAOs improved from 16° (+-6) to a mean of 34° (+-6°) and the mean acetabular index (AI) was corrected from 15° (+-4) to 2° (+-4). This implements highly physiologic postoperative values for lateral coverage in this population. In this case series, no postoperative acetabular retroversion was measured in any of the 27 PAOs. CONCLUSION: Three-dimensional control of the acetabular orientation during periacetabular osteotomy is important to avoid over- and undercorrection. Using a fixateur externe as an analog navigation method this three-dimensional control can be implemented intraoperatively for PAOs.

Postural stability after operative reconstruction of the AFTL in chronic ankle instability comparing three different surgical techniques.

Background: Chronic lateral ankle instability is a relatively frequent consequence after acute ankle sprain. In case of unsuccessful conservative treatment, surgical therapy is recommended to prevent osteoarthritis of the ankle joint. To date, different surgical methods have evolved. Yet, it remains unclear which approach reveals the best results. We hypothesized that the modified Broström-Gould procedure with suture anchor ligament fixation leads to superior postoperative results compared to the Broström-Gould procedure or the periosteal flap technique. Material and methods: In a prospective study, we examined the three surgical techniques. For this purpose, we performed a matched-pair analysis with four groups according to age, sex, and body mass index: periosteal flap technique (G1), Broström-Gould procedure (G2), modified Broström-Gould procedure with suture anchor ligament fixation (G3), and a control group (G4). Results were compared with the American Orthopaedic Foot & Ankle Society (AOFAS) score, a functional analysis as well as measuring postural stability with the Biodex balance system. Results: No significant differences were found between all four groups concerning AOFAS score, functional results, as well as postural stability. Conclusion: All three surgical methods revealed satisfactory results. No significant differences could be detected in clinical and functional categories. The Broström-Gould method as well as the modified procedure with anchor can be recommended as surgical therapy for chronic lateral ankle instability. Additional anchors do not seem to have a significant positive impact on the results.

Favourable mid-term isokinetic strength after primary THA combined with a modified enhanced recovery after surgery concept (ERAS) in a single blinded randomized controlled trial.

PURPOSE: Muscular deficits as part of severe osteoarthritis of the hip may persist for up to two years following total hip arthroplasty (THA). No study has evaluated the mid-term benefit of a modified enhanced-recovery-after-surgery (ERAS) concept on muscular strength of the hip in detail thus far. We (1) investigated if a modified ERAS-concept for primary THA improves the mid-term rehabilitation of muscular strength and (2) compared the clinical outcome using validated clinical scores. METHODS: In a prospective, single-blinded, randomized controlled trial we compared patients receiving primary THA with a modified ERAS concept (n = 12, ERAS-group) and such receiving conventional THA (n = 12, non-ERAS) at three months and one year postoperatively. For assessment of isokinetic muscular strength, a Biodex-Dynamometer was used (peak-torque, total-work, power). The clinical outcome was evaluated by using clinical scores (Patient-Related-Outcome-Measures (PROMs), WOMAC-index (Western-Ontario-and-McMaster-Universities-Osteoarthritis-Index), HHS (Harris-Hip-Score) and EQ-5D-3L-score. RESULTS: Three-months postoperatively, isokinetic strength (peak-torque, total-work, power) and active range of motion was significantly better in the modified ERAS group. One year postoperatively, the total work for flexion was significantly higher than in the Non-ERAS group, whilst peak-torque and power did not show significant differences. Evaluation of clinical scores revealed excellent results at both time points in both groups. However, we could not detect any significant differences between both groups in respect of the clinical outcome. CONCLUSION: With regard to muscular strength, this study supports the implementation of an ERAS concept for primary THA. The combination with a modified ERAS concept lead to faster rehabilitation for up to one-year postoperatively, reflected by significant higher muscular strength (peak-torque, total-work, power). Possibly, because common scores are not sensitive enough, the results are not reflected in the clinical outcome. Further larger randomized controlled trials are necessary for long-term evaluation.

A New Methodology for the Accurate Measurement of Tibiofemoral Kinematics in Human Cadaveric Knees: An Evaluation of the Anterior-Posterior Laxity Pre- and Post-Cruciate Ligament Resection.

Anterior-posterior (AP) stability is an important measure of knee performance after total knee arthroplasty (TKA). To improve the stabilizing effect of implants designed to compensate for the loss of the cruciate ligaments, it is important to understand the tibiofemoral contact situation within the native ligamentous situation of the knee and how it changes after cruciate ligament resection. This in vitro study introduces a new approach to accurately measure the tibiofemoral kinematics in a six-degrees-of-freedom joint motion simulator by tracking landmark-based coordinate systems and their corresponding bone geometries. The tibiofemoral contact situation was investigated by projecting the medial and lateral flexion facet centers onto the tibial plateau under AP shear forces across various flexion angles in thirteen knees. Tests were conducted pre- and post-cruciate ligament resection. Post-cruciate ligament resection, the femoral condyles shifted closer to or even exceeded the posterior border of the tibial plateau, but only slightly closer to the anterior border. This study presents a new methodology for measuring the tibiofemoral kinematics that can be applied to multiple loading profiles. It provides a basis for further investigations, including passive or active muscle forces, to enhance the design of total knee protheses and improve surgical outcomes.

Periprosthetic Joint Infections of the Knee-Comparison of Different Treatment Algorithms.

Background: Periprosthetic joint infection (PJI) following total knee arthroplasty is a serious complication lacking evidence-based diagnostic and treatment protocols, particularly in ruling out persisting infection before reimplantation. Methods: This retrospective analysis assessed the mid-term outcomes of 66 patients undergoing septic two-stage knee revision surgeries from 2007 to 2013, diagnosed as per the Musculoskeletal Infection Society criteria. After implant removal and antibiotic treatment, reimplantation decisions were based on either joint aspiration, blood counts, and clinical examination (group A) or an open biopsy (group B). Both groups underwent meticulous debridement and spacer exchange during the interim period. Results: Late re-infection occurred in 12.1% of all patients. In group A, 13.8% experienced late re-infection, with 14.3% in subgroup A1 and 13.3% in subgroup A2. In group B, 10% had a late re-infection. No significant difference in re-infection or complication rates was found between the groups. Conclusions: The study did not demonstrate the superiority of group B's approach of open biopsy over group A's joint aspiration, clinical examination, and blood counts in preventing re-infection or reducing complications.

Postural Stability and Pedobarography After Reconstruction of Peroneus Brevis Tendon Split Lesion.

PURPOSE: Lesions of the peroneal tendons are frequently overseen after ankle sprain. The symptoms consist of stress-dependent pain that extends from the inframalleolar to the proximal part along the course of the peroneal tendons as well as ankle instability and soft-tissue swelling. In case of unsuccessful conservative treatment, surgical therapy is recommended. The aim of the study was to evaluate the clinical and functional outcome after open reconstruction of the peroneus brevis tendon. METHODS: 13 patients were included in this retrospective study. All of them received a single reconstruction of the peroneus brevis tendon in open technique. Postoperative results were evaluated with the AOFAS score, a functional and perdobargraphic analysis as well as measuring postural stability with the Biodex balance system. The participants were matched with a healthy control group according to age, sex and BMI. RESULTS: The results of the AOFAS score showed significantly convincing results in all subscores postoperatively. A bilateral comparison of the postural stability showed that the affected side had become functionally similar to the healthy side. No statistical significant difference was detected concerning both one-legged and two-legged standing with the control group. Pedobarographic results revealed no difference between the affected and contralateral side, as well as between the patients and the healthy control group. CONCLUSION: Open reconstruction of the peroneus brevis tendon leads to significant better postoperative results and can be recommended after unsuccessful conservative treatment as promising option.

Impressive Short-Term Improvement in Functional Outcome and Quality of Life after Primary Total Hip Arthroplasty (THA) in the Orthogeriatric Patient in a Prospective Monocentric Trial.

Background/Objectives: Osteoarthritis (OA) represents the most frequent chronic joint disease worldwide. Facing an aging population, resulting from the demographic change, the number of primary total hip arthroplasties (THA) will further increase. Although the geriatric patient strongly differs from the younger one, the current literature on elective orthopedic surgery in the geriatric patient is scarce. This work analyses, whether geriatric patients receiving primary THA significantly improve in terms of their (1) mobility and functional outcome and (2) health-related quality of life at four to six weeks as well as three months postoperatively. Methods: In a prospective study design, we analyzed 101 geriatric patients with osteoarthritis of the hip receiving primary THA. The study is part of the ongoing "Special Orthopaedic Geriatrics" (SOG) trial, which is funded by the German Federal Joint Committee (GBA). In addition to a preoperative comprehensive geriatric assessment (CGA), the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and the EQ5D-5L were imposed preoperatively (t0), at four to six weeks (t1), and at three months (t2) postoperatively. Results: The 101 enrolled patients had a mean age of 78.1 ± 4.9 years. The total WOMAC score and almost all subcategories significantly improved at four to six weeks as well as three months postoperatively in comparison to the preoperative results (p < 0.001). The same was observed for the EQ-5D-5L, showing significant improvement in overall health at both time points (p < 0.001) and all subcategories (p < 0.05). Conclusions: This study implies that a geriatric patient benefits as much from elective primary THA as a younger patient. However, the preoperative comprehensive geriatric assessment with screening for risk factors is of utmost importance. Regarding the aging population, a lot of effort is needed to obtain more knowledge about geriatric patients receiving elective orthopedic surgery.

A randomized controlled trial demonstrating sustained benefit of autologous matrix-induced chondrogenesis (AMIC®) over microfracture: 10-year follow-up.

PURPOSE: Autologous matrix-induced chondrogenesis (AMIC®) and microfracture are established treatments for focal chondral defects in the knee, but there are little clinical data concerning these procedures over the long term. This study evaluates the outcomes of AMIC® compared to microfracture over 10-year follow-up. METHODS: Forty-seven patients were randomized and treated either with MFx (n = 13), sutured AMIC® (n = 17) or glued AMIC® (n = 17) in a prospective, randomized, controlled multicentre trial. The Modified Cincinnati Knee Score, a visual analogue scale for pain and MOCART score were used to assess outcomes over 10 years post-operatively. RESULTS: All treatment arms improved in the first 2 years, but a progressive and significant deterioration in scores was observed in the MFx group, while both AMIC® groups remained stable. MOCART scores were comparable between groups. CONCLUSION: The AMIC® procedure results in improved patient outcomes in comparison with microfracture up to 10 years following surgery for the repair of focal chondral defects in the knee. CLINICALTRIALS: gov Identifier: NCT02993510.

[Risk and complication profiles of orthogeriatric patients in elective hip and knee joint replacement]. / Risiko- und Komplikationsprofil orthogeriatrischer Patienten bei elektivem Hüft- und Kniegelenkersatz.

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.

[Fast-Track-Arthroplasty]. / Fast-Track-Endoprothetik.

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.

[SOG-Special Orthopedic Geriatrics : First interim results of a randomized controlled study on integrated orthogeriatric care in elective hip and knee arthroplasty]. / SOG ­ Spezielle Orthopädische Geriatrie : Erste Zwischenergebnisse einer randomisierten kontrollierten Studie zur integrierten orthogeriatrischen Versorgung in der elektiven Hüft- und Kniegelenkendoprothetik.

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.

[Navigation and robotics-current status and future implications]. / Navigation und Robotik ­ status präsens und zukünftige Implikationen.

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.

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.

[Trends in navigation-handheld systems]. / Trends in der Navigation ­ Handheld-Systeme.

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.

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.

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.

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.

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.