Medial Patellofemoral Ligament Reconstruction Using Pedicled Quadriceps Tendon Autograft Yields Similar Clinical and Patient-Reported Outcomes but Less Donor-Site Morbidity Compared With Gracilis Tendon Autograft.

PURPOSE: To compare clinical and patient-reported outcome measures (PROMs) in patients with recurrent patellar dislocation after medial patellofemoral ligament (MPFL) reconstruction using either a gracilis tendon (GT) or quadriceps tendon autograft (QT). METHODS: All MPFL reconstruction performed between 2017 and 2019 were reviewed retrospectively. Only patients with isolated MPFL reconstruction, without any major patellofemoral risk factors and a minimum follow-up of 24 months, were included in the study. Patients were matched with respect to sex, age, and body mass index. All patients were evaluated clinically and using PROMs. RESULTS: A total of 64 patients with an average follow up of 28.7 ± 7.5 months were included in this study. The mean Kujala score (GT: 84.8 ± 12.9, QT: 88.9 ± 10.1), Lysholm score (GT: 89.4 ± 10.2, QT: 88.4 ± 5.0), and visual analog scale score for pain (GT: 1.9 ± 1.8, QT: 1.1 ± 1.3) did not significantly differ between both groups. Tegner activity level was significantly greater (P = .027) in the QT group (5.5 ± 1.9) compared with the GT group (4.6 ± 1.8), but within the minimal clinically important differences. Occasional patellar instability events, but no recurrent dislocation, were reported in 12.5% in the GT group and 6.3% in the QT group (P = .39). Of all patients, 90.6% in the QT and 68.8% in the HT group exceeded the PASS for the Kujala score (P = .06). Significantly more patients (59.4%) treated with GT reported donor-site morbidity in the form of sensitivity deficit at the lower leg compared with those treated with QT (3.1%, P = .001). CONCLUSIONS: GT and QT MPFL reconstruction have comparable PROMs and patellar redislocation rates 2 years' postoperatively. Significantly more patients treated with GT reported lower-leg sensitivity deficit compared with those treated with QT. LEVEL OF EVIDENCE: Level III, retrospective case-control study.

No significant difference in early clinical outcomes of custom versus off-the-shelf total knee arthroplasty: a systematic review and meta-analysis.

PURPOSE: The purpose of this systematic review and meta-analysis was to collect, synthesise and critically appraise findings of clinical studies that report outcomes of custom total knee arthroplasty (TKA). The hypothesis was that, compared to off-the-shelf (OTS) TKA, custom TKA would yield better surgical, clinical and radiographic outcomes. METHODS: This systematic review and meta-analysis was performed in accordance with the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). On 8 February 2021, two authors independently searched and screened articles using MEDLINE®, Embase® and the Cochrane Library without restriction on date of publication. Findings from eligible articles were narratively synthesised and tabulated, and when ≥ 3 comparative studies reported the same outcome, results were pooled and summarised in forest plots. Quality assessments of the studies were done according to the guidelines of the Joanna Briggs Institute (JBI) Checklists. RESULTS: A total of 15 articles were eligible for data extraction, of which 9 were case-control studies reporting on 929 custom versus 998 OTS TKA, 5 were case series reporting on results of 587 custom TKA, and 1 was a cross-sectional study reporting on results of 44 custom versus 132 OTS TKA. Five studies that compared early revision rates found the overall effect in favour of OTS TKA (odds ratio (OR), 0.4; p = n.s.) but the result did not reach statistical significance. Four studies found no statistically significant difference in KSS knee (standardised mean difference (SMD), - 0.10; p = n.s.) and function (SMD, 0.03; p = n.s.), and five studies found no statistically significant difference in range of motion (SMD, 0.02; p = n.s.). One study that compared bone-implant fit between custom and three OTS tibial components found no overhang but revealed under-coverage of up to 18% in knees with custom tibial baseplates. CONCLUSION: Custom TKA demonstrated no significant benefits compared to OTS TKA in terms of pooled clinical outcomes, but had considerably higher early revision rates. The findings of the present systematic review and meta-analysis suggest the need for studies with better comparable groups and standardisation of reporting outcomes amongst studies, that could increase the quality of evidence and enable pooling of results in future meta-analyses. LEVEL OF EVIDENCE: Level IV.

Total knee arthroplasty without patella resurfacing leads to worse results in patients with patellafemoral osteoarthritis Iwano Stages 3-4: a study based on arthroplasty registry data.

PURPOSE: To determine whether the preoperative degree of degeneration of the patellofemoral joint really affects the outcome of total knee arthroplasty (TKA) surgery without patella resurfacing and thus to establish a parameter that might serve as a guiding factor to decide whether or not to perform retropatellar resurfacing. It was hypothesized that patients with preoperative mild patellofemoral osteoarthritis (Iwano Stages 0-2) would significantly differ from patients with preoperative severe patellofemoral osteoarthritis (Iwano Stages 3-4) in terms of patient-reported outcome (Hypothesis 1) and revision rates/survival (Hypothesis 2) after TKA without patella resurfacing. METHODS: Application of a retrospective-comparative design on the basis of Arthroplasty Registry data that included patients with primary TKA without patella resurfacing. Patients were allocated to the following groups based on preoperative radiographic stage of patellofemoral joint degeneration: (a) mild patellofemoral osteoarthritis (Iwano Stage ≤ 2) and (b) severe patellofemoral osteoarthritis (Iwano Stages 3-4). The Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC) score was assessed preoperative and 1 year postoperative (0: best, 100 worst). In addition, implant survival was calculated from the Arthroplasty Registry data. RESULTS: In 1209 primary TKA without patella resurfacing, postoperative WOMAC total and WOMAC subscores did not differ significantly between groups, but potentially suffered from type 2 error. Three-year survival was 97.4% and 92.5% in patients with preoperative mild and severe patellofemoral osteoarthritis, respectively (p = 0.002). Five-year survival was 95.8% vs. 91.4% (p = 0.033) and 10-year survival was 93.3% vs. 88.6% (p = 0.033), respectively. CONCLUSIONS: From the study findings, it is concluded that patients with preoperative severe patellofemoral osteoarthritis have significantly higher risks for reoperation than do those with preoperative mild patellofemoral osteoarthritis-when treated with TKA without patella resurfacing. Hence, it is recommended that patella resurfacing be applied in patients with severe Iwano Stage 3 or 4 patellofemoral osteoarthritis during TKA. LEVEL OF EVIDENCE: III, Retrospective comparative.

Clinical outcomes in latissimus dorsi transfer single- versus double-incision technique.

BACKGROUND/HYPOTHESIS: In patients with irreparable postero-superior rotator cuff lesions, a latissimus dorsi transfer (LDT) is performed. For this surgery, different techniques are used. In this study, we aim to compare the patient's functional outcome after treatment with modified L'Episcopo "single-incision" and modified Gerber "double-incision" technique for LDT. METHODS: 44 patients with irreparable postero-superior rotator cuff ruptures, refractory to physiotherapeutic treatment were included. 21 patients were treated using a modified L'Episcopo "single-incision", 23 patients with modified Gerber "double-incision" surgical approach. All patients had full-thickness tears of at least two complete tendons, and all had fully functioning deltoid and subscapularis muscles. Preoperatively, there were statistically significant differences between the two groups in all preoperative CMS sub-parameters except "power" and "pain". In the postoperative follow-up, a functional assessment using "Constant-Murley Score" (CMS) and "Age- and gender-related CMS" was conducted. STUDY DESIGN: Retrospective-comparative trial. RESULTS: There were no statistically significant differences between age, sex and time of follow-up between the two study groups (p > 0.05). The mean age was 59.2(± 6.3) years, and the mean follow-up time was 45.4(± 9.3) months for both groups taken together. Mean CMS improved for both groups together from 24.2 ± 8.2 points prior to surgery, to 62.8 ± 17.4 points after a mean follow-up time of 45.4 ± 9.3 months post surgery. The patients treated with "single-incision" surgery (n = 21) gained significantly (p < 0.001) more in CMS and all CMS-sub-scoring parameters except power and pain, compared to the patients treated with "double-incision" technique (n = 23). CONCLUSION: This survey shows appealing post-operative functional outcome in patients with irreparable postero-superior rotator cuff lesions treated with two different techniques for LDT. We believe that the presentation of these methods and their results might encourage shoulder surgeons to implement these techniques. Especially the "single-incision" LDT surgery might be a more accustomed technique for many shoulder surgeons well trained in the deltopectoral approach.

Radiographic and clinical outcome of tibial plateau fractures treated with bone allograft.

BACKGROUND: To determine the clinical outcome of patients who had been treated with bone allografts during open reduction and internal fixation (ORIF) of tibial head fractures. METHODS: Patients who suffered a medial, lateral, or bicondylar fracture of the tibial plateau and underwent surgical treatment by open reduction and internal fixation (ORIF) using human femoral head bone allografts were included. Patients were invited to provide information for the following: Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), EuroQol Five Dimension score (EQ-5D), Lower Extremity Functional Scale (LEFS) and Parker Mobility Score. Bone mineral density (BMD) of the allograft area and the healthy human bone tissue were measured by quantitative computed tomography. RESULTS: A total of 22 patients with a mean follow-up time of 2.88 ± 2.46 years were included in our study. The most common fractures observed in this study were classified as Schatzker II (11 patients, 50.0%) or AO/OTA 41.B3 (12 patients, 54.5%) fractures. Postoperative WOMAC total was 13.0 (IQR = 16.3, range 0-33). Median quality of life (EQ-5D) score was 0.887 ± 0.121 (range 0.361-1.000). Median Lower Extremity Functional Scale (LEFS) score was 57.5 ± 19.0 (range 33-79). Mean Parker Mobility Score was 9 (range 6-9). Median bone mineral density (BMD) for the whole group was 300.04 ± 226.02 mg/cm3 (range - 88.68 to 555.06 mg/cm3) for region of interest (ROI 5) (central), 214.80 ± 167.45 mg/cm3 (range - 7.16 to 597.21 mg/cm3) for ROI 1-4 (marginal zones: medial, lateral, ventral, dorsal) and 168.14 ± 65.54 mg/cm3 (range 17.47-208.97 mg/cm3) for healthy bone tissue (femur and tibia). CONCLUSION: Based on WOMAC scores, LEFS, ambulatory status, and quality of life findings, it can be concluded that following tibial head ORIF with allograft bone patients has promising results.

Moonlight surgery: no influence of moon phase or Friday 13th on outcomes of total knee arthroplasty.

OBJECTIVES: The purpose of the present study was to investigate associations between revision-free survival and functional scores of total knee arthroplasty (TKA) and moon phase on the day of surgery, as well as operations performed on a Friday 13th. PARTICIPANTS: The data of all patients that received TKA between 2003 and 2019 were extracted from the Tyrol arthroplasty registry. Patients that had undergone previous total or partial knee arthroplasty as well as patients that had missing pre- or post-operative WOMAC were excluded. Patients were allocated to one of the following four groups according to moon phase on the day of surgery: new, waxing, full and waning. Patients operated on a Friday 13th were also identified and compared to patients operated on any other days/dates. A total of 5923 patients met the inclusion criteria, with mean age of 69 ± 9 years, and comprising 62% women. RESULTS: There were no significant differences in revision-free survival among the four moon phase groups (p = 0.479), and no significant differences in preoperative and postoperative total WOMAC (p = 0.260, p = 0.122), There were no significant differences in revision-free survival patients operated on Friday 13th vs. other days/dates (p = 0.440). The preoperative total WOMAC was significantly worse for patients operated on a Friday 13th (p = 0.013), which was observed in the pain (p = 0.032) and function (p = 0.010) subscales. There were no significant differences in postoperative total WOMAC at 1 year follow-up (p = 0.122). CONCLUSIONS: Neither moon phase on the day of surgery nor Friday 13th were associated with revision-free survival or clinical scores of TKA. Patients operated on a Friday 13th had significantly worse preoperative total WOMAC but similar postoperative total WOMAC at 1-year follow-up. These findings could help reassure patients that TKA renders consistent outcomes regardless of the preoperative pain or function, and in spite of bad omens or moon phases.

Driving ability after right-sided inguinal hernia surgery.

PURPOSE: To investigate driving ability (brake reaction time, BRT) after right-sided hernia repair. It was assumed that postoperatively BRT would be impaired as compared to the preoperative reference and healthy controls. METHODS: BRT was prospectively collected from 30 patients undergoing hernia repair [Lichtenstein or total extraperitoneal endoscopic procedure (TEP)]. BRT was measured with a driving simulator preoperatively and on postoperative days 2 and 14. After receiving a visual stimulus, the patients had to apply the brake pedal with 160 N. The average of ten runs was used as the patient's BRT value. RESULTS: Thirty patients completed all measurements. In the Lichtenstein group, BRT was significantly impaired as compared to the patient's preoperative values (p = 0.021). Two weeks after surgery BRT had returned to the preoperative level (p = 0.859). BRT in the Lichtenstein group was also significantly impaired 2 days postoperatively as compared to the BRT of 60 healthy controls (p = 0.001). In the TEP group, no impaired BRT was detected. CONCLUSIONS: Based on our finding of significantly impaired BRT in patients following right-sided Lichtenstein hernia repair, it seems wise to recommend that such patients refrain from driving for 2 weeks after surgery. No such impairment was found in patients following TEP surgery. Consequently, it is deemed safe for them to resume driving 2 days after the procedure.

Insufficient evidence to confirm benefits of custom partial knee arthroplasty: a systematic review.

PURPOSE: The purpose of this systematic review was to synthesise the available literature and critically appraise current evidence on the functional and radiographic outcomes as well as reoperation and revision rates of custom partial knee arthroplasty, i.e., unicompartmental knee arthroplasty (UKA), bicompartmental knee arthroplasty (BKA), and patellofemoral arthroplasty (PFA). MATERIAL AND METHODS: This systematic review was performed in accordance with the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), and a protocol was registered with Prospero. On 25 May 2021, two authors independently searched and screened Level I-IV studies that reported on outcomes of custom partial knee arthroplasty using the databases of MEDLINE®, EMBASE®, and the Cochrane Library without restriction on date of publication. Findings from eligible articles were synthesised and tabulated, and quality assessments were done according to the guidelines of the Joanna Briggs Institute (JBI) Checklists. RESULTS: Fifteen articles were eligible for data extraction, of which two comparative and four case series were on custom UKA (follow-up, 0-9 months), one comparative and five case series on custom BKA (follow-up, 0.25-72 months), and three case series on custom PFA (follow-up, 2-119 months). Three studies on custom UKA reported mean Knee Society Score (KSS) Knee of 86-94 and mean KSS Function of 94-95, and two studies on custom BKA reported mean KSS Knee of 90-94 and KSS function of 81, whereas one study on custom PFA reported KSS Knee of 91 and KSS Function of 89. Custom implants tended to have less bone-implant mismatch compared to off the shelf (OTS) implants. Revision rates were 3-25% for custom UKA (at 0-109 months), 3-5% for custom BKA (at 12-72 months), and 0-14% for custom PFA (at 2-119 months). CONCLUSION: Due to the small number of comparative studies and lack of consistency in reported outcomes, it remains difficult to ascertain the benefits of custom partial knee arthroplasty. Anecdotal evidence suggests that, compared to OTS implants, custom implants result in less bone-implant mismatch and that 78-91% of patients are either satisfied or very satisfied after custom partial knee arthroplasty. LEVEL OF EVIDENCE: IV.

Medial unicondylar knee arthroplasty should be reserved for patients with complete joint space collapse.

PURPOSE: To determine whether preoperative radiologic joint space width (JSW) is related to the outcome of medial unicondylar knee arthroplasty (UKA) (primary hypothesis). METHODS: A retrospective comparative analysis was performed. One group was comprised of UKA patients with preoperative JSW 0-1 mm. Another group was made up of patients with preoperative JSW ≥ 2 mm (range 0-4 mm). The JSW was measured from preoperative weight-bearing Schuss-view radiographs. The clinical outcome was determined with the Western Ontario and MacMaster Universities (WOMAC) Osteoarthritis Index score preoperatively and 1 year after medial UKA. Implant survival data were obtained from the arthroplasty register of Tyrol. RESULTS: There were 80 patients with a preoperative JSW 0-1 mm (age 66, BMI 27.8) and 70 patients with a preoperative JSW ≥ 2 mm (age 64, IQR 15, BMI 28.1). WOMAC total was 10 ± 10 in patients with 0-1 mm JSW and 25 ± 47 in patients with ≥ 2 mm JSW at 1 year postoperative (p = 0.052). WOMAC pain at 1 year postoperative was 7 ± 16 in patients with 0-1 mm JSW and 18 ± 46 in patients with ≥ 2 mm JSW (p = 0.047). WOMAC function at 1 year postoperative was 10 ± 9 in patients with 0-1 mm JSW and 17 ± 51 in patients with ≥ 2 mm JSW (p = 0.048). In patients with 0-1 mm JSW 5 year prosthesis survival was 92.3% and in patients with ≥ 2 mm JSW, it was 81.1% (p = 0.016). CONCLUSIONS: In patients with preoperative complete joint space collapse (0-1 mm JSW), clinical outcome was superior to that of patients with incomplete joint space collapse. This was true for both 1 year postoperative WOMAC pain and WOMAC function and for 5 year implant survival rates. On the basis of our findings, it is recommended that 'complete joint space collapse' especially be used to achieve best clinical outcome in medial UKA surgery. LEVEL OF EVIDENCE: IV.

Injuries to the anterolateral ligament are observed more frequently compared to lesions to the deep iliotibial tract (Kaplan fibers) in anterior cruciate ligamant deficient knees using magnetic resonance imaging.

PURPOSE: To determine the accuracy of detection, injury rate and inter- and intrarater reproducibility in visualizing lesions to the anterolateral ligament (ALL) and the deep portion of the iliotibial tract (dITT) in anterior cruciate ligament (ACL) deficient knees. METHODS: Ninety-one consecutive patients, out of those 25 children (age 14.3 ± 3.5 years), with diagnosed ACL tears were included. Two musculoskeletal radiologists retrospectively reviewed MRI data focusing on accuracy of detection and potential injuries to the ALL or dITT. Lesion were diagnosed in case of discontinued fibers in combination with intra- or peri-ligamentous edema and graded as intact, partial or complete tears. Cohen's Kappa and 95% confidence intervals (95% CI) were determined for inter- and intrarater reliability measures. RESULTS: The ALL and dITT were visible in 52 (78.8%) and 56 (84.8%) of adult-and 25 (100%) and 19 (76.0%) of pediatric patients, respectively. The ALL was injured in 45 (58.5%; partial: 36.4%, compleate: 22.1%) patients. Partial and comleate tears, where visualized in 21 (40.4%) and 16 (30.8%) adult- and seven (28.0%) and one (4%) peditric patients. A total of 16 (21.3%; partial: 13.3%, compleate: 8.0%) dITT injuries were identified. Partal and complete lesions were seen in seven (12.5%) and five (8.9%) adult- and three (15.8%) and one (5.3%) pediatric patients. Combined injuries were visualized in nine (12.7%) patients. Inter-observer (0.91-0.95) and intra-observer (0.93-0.95) reproducibility was high. CONCLUSION: In ACL injured knees, tears of the ALL are observed more frequently compared to lesions to the deep iliotibial tract. Combined injuries of both structures are rare. Clinically, the preoperative visualization of potentially injured structures of the anterolateral knee is crucial and is important for a more personalized preoperative planning and tailored anatomical reconstruction. The clinical implication of injuries to the anterolateral complex of the knee needs further investigation. LEVEL OF EVIDENCE: II.

A Prospective Assessment of Knee Arthroscopy Skills Between Medical Students and Residents-Simulator Exercises for Partial Meniscectomy and Analysis of Learning Curves.

BACKGROUND: The Covid-19 pandemic has created the largest disruption of education in history. In a response to this, we aimed to evaluate the knee arthroscopy learning curve among medical students and orthopaedic residents. METHODS: An arthroscopy simulator was used to compare the learning curves of two groups. Medical students with any prior knowledge of arthroscopy (n=24) were compared to a residents group (n=16). Analyzed parameters were "time to complete a task," assessment of the movement of tools and values scoring damage to the surrounding tissues. RESULTS: After several repetitions, both groups improved their skills in terms of time and movement. Residents were on average faster, had less camera movement, and touched the cartilage tissue less often than did students. Students showed a steeper improvement curve than residents for certain parameters, as they started from a different experience level. CONCLUSION: The participants were able to reduce the time to complete a task. There was also a decrease in possible damage to the virtual surrounding tissues. In general, the residents had better mean values, but the students had the steeper learning curve. Particularly less experienced surgeons can especially train their hand-eye coordination skills required for arthroscopy surgery. Training simulators are an important training tool that supplements cadaveric training and participation in arthroscopic operations and should be included in training.

High range of motion in the first ten postoperative days after TKA does not predict superior outcome in the long run.

INTRODUCTION: To retrospectively investigate the early postoperative range of motion (ROM) (days 4, 7, 10) after total knee arthroplasty (TKA) and to test for associations (a) with long-term outcome in terms of ROM and (b) with a disease-specific knee score. MATERIALS AND METHODS: A retrospective analysis was performed in patients with previous primary TKA. Data taken from the medical records were ROM from preoperative and postoperative days 4, 7 and 10 and 1 year. As patient-reported outcome the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC Score) was taken from preoperative and one year after TKA. RESULTS: 316 patients (330 knees) were available. Only negligible correlations were determined between ROM at twelve months postoperative and ROM in the early postoperative days (days 4, 7, 10). Similarly, only negligible correlations were determined between ROM in the early postoperative days (days 4, 7, 10) and the 1-year WOMAC. CONCLUSION: From the main findings it would seem that steepness of ROM ascent in the early postoperative days is of minor importance for (a) long-term ROM and (b) long-term knee score outcome after TKA.

Migration characteristics of the Corail hydroxyapatite-coated femoral stem-a retrospective clinical evaluation and migration measurement with EBRA.

PURPOSE: Uncemented stem migration analysis by EBRA-FCA (Einzel-Bild-Roentgen Analyse, Femoral Component Analysis) has been seen to be a good predictive indicator for early implant failure. In this study, we investigated the migration behavior of a cementless press-fit stem after two years follow-up. Stem type and postoperative gap between collar and femur were evaluated as a risk factor. METHODS: Applying a retrospective study design, we reviewed all consecutive patients who between 2013 and 2017 received a cementless press-fit Corail stem (DePuy Orthopaedics Inc., Warsaw, IN, USA) at our Department. We reviewed medical histories and performed radiological measurements using EBRA-FCA software. RESULTS: A total of 109 stems in 105 patients (female: 60; male: 45) fulfilled our inclusion criteria. Mean age at surgery was 67.8 (range, 21.6-90.5) years. EBRA migration analysis showed a mean subsidence of 1.8 mm (range, 0.0-12.1) at final follow-up. At 18 months mean subsidence of collared stems was significantly lower than in the collarless group [1.3 mm (range, 0.0-7.6) vs. 3.2 mm (range, 0.5-10.7), p = 0.0104]. Collared stems resting on the femoral cut presented a tendency to less subsidence than did collared stems showing a postoperative gap between collar and femur (1.3 vs. 2.0 mm) without finding statistical significance (p > 0.05). CONCLUSIONS: Low subsidence and the migration pattern of the cementless press-fit stem may predict a good long-term result. Collared stems investigated in our study provide good stability and are able to prevent significant subsidence. Trial registration number and date of registration: Number: 20181024-1875; Date: 2018-10-24.

Subsidence of a metaphyseal-anchored press-fit stem after 4-year follow-up: an EBRA-FCA analysis.

PURPOSE: Uncemented stem migration analysis by EBRA-FCA (Einzel-Bild-Roentgen Analyse, Femoral Component Analyse) has been seen to be a good predictive indicator for early implant failure. In this study, we investigated the migration behavior of a cementless metaphyseal-anchored press-fit stem after 4-year follow-up. METHODS: Applying a retrospective study design, we reviewed all consecutive patients who between 2012 and 2017 received a cementless Accolade II press-fit stem at our Department. We reviewed medical histories and performed radiological measurements using EBRA-FCA software. EBRA-FCA measurements and statistical investigations were performed by two independent investigators. RESULTS: A total of 102 stems in 91 patients (female 60; male 31) fulfilled our inclusion criteria. Mean age at surgery was 66.2 (range 24.3-92.6) years. EBRA migration analysis showed a mean subsidence of 1.4 mm (range 0.0-12.0) at final follow-up. The angle between stem and femur axis was 0.5° (range 0.0°-2.8°) after 48 months. No correlations between gender or Dorr types and subsidence were found (p > 0.05). A body mass index > 30 kg/m2 showed a significant increase in stem subsidence within the first 6 (p = 0.0258) and 12 months (p = 0.0466) postoperative. CONCLUSIONS: Migration pattern of the metaphyseal-anchored stem and a low subsidence rate at final follow-up may predict a good long-term clinical result. TRIAL REGISTRATION: Number: 20181024-1875.

Linear Anterior-Posterior Computed Tomography Parameters Used to Quantify Trochlear Dysplasia Are More Reliable Than Angular Measurements.

PURPOSE: (1) To evaluate the reliability of 9 commonly used quantitative parameters of the trochlear morphology on computed tomography (CT) and (2) to analyze for differences in the reliability regarding patient subgroups (patellofemoral instability [PFI] vs non-PFI). METHODS: A retrospective analysis of lower-limb CT scans performed between August 1996 and February 2013 was performed. The CT scans of all patients with PFI and 30 randomly selected cases without a history of PFI (non-PFI) were included. The following measurements were performed on 1 proximal axial CT slice at the entrance of the trochlear groove and 1 slice 5 mm further distal: relative medial, central, and lateral trochlear height; trochlear depth; relative transverse trochlear shift; trochlear facet asymmetry; sulcus angle; and medial and lateral trochlear slope. Four investigators performed the measurements independently, and intraclass correlation coefficients (ICCs) were calculated for the entire study group, as well as for the PFI and non-PFI groups separately. RESULTS: In total, 66 cases (36 PFI cases) were included in the study. We found almost perfect inter-rater and intrarater agreement for the trochlear height on both axial CT slices (ICC, 0.831-0.977). For the other measurements, we found only fair reliability (ICC < 0.4) on the proximal CT slice, whereas on the distal CT slice, at least moderate reliability (ICC > 0.4) was observed. ICCs were lower for many parameters in the PFI group. Angular values were less reliable than linear values. In particular, measurements involving the medial facet (i.e., sulcus angle, medial trochlear slope, and trochlear facet asymmetry) were less reliable. CONCLUSIONS: When interpreting quantitative parameters defining the trochlear morphology, one must taken into account the considerably lower reliability of angular parameters such as the commonly used sulcus angle compared with linear measurements. Radiologic measurements are less reliable in cases of PFI than in subjects without instability. LEVEL OF EVIDENCE: Level III, retrospective case-control study.

Twenty-one sports activities are recommended by the European Knee Associates (EKA) six months after total knee arthroplasty.

PURPOSE: To elaborate recommendations for sports participation following TKA among the members of the European Knee Associates (EKA). METHODS: A prospective online survey was conducted among the members of the European Knee Associates (EKA). The European Knee Associates (EKA) are a section of the European Society of Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA). The survey investigated recommendations for 47 sports disciplines. Possible answers were: allowed, allowed if experienced, not allowed, no opinion. The survey was conducted separately for 4 specific time frames: within 6 weeks after TKA; 6-12 weeks after TKA; 3-6 months after TKA; and more than 6 months after TKA. Consensus among the respondents was then analyzed. RESULTS: EKA members (N = 120) participated in the survey. A high level of consensus was reached for a recommendation to allow 5 different sports in the first 6 weeks after TKA, 7 sports 6-12 weeks after surgery, 14 sports 3-6 months after TKA, and 21 out of 47 activities 6 months after surgery. In the first 6 weeks after TKA walking, stair climbing, swimming, aqua fitness, and static cycling were recommended. Six to twelve weeks after TKA, cycling on level ground and yoga were recommended in addition to the aforementioned activities. Further sports activities recommended beyond 12 weeks after TKA were: tennis doubles, golf, fitness/weight lifting, aerobics, hiking, Nordic walking and sailing. The sport for which the recommendation was "not allowed" following TKA was squash. CONCLUSION: The number of sports recommended by EKA surgeons increases stepwise over the postoperative time frames. The findings are regarded as clinically relevant as they may serve as a basis for answering patient questions on timing and giving recommendations for the resumption of sports activities following standard primary TKA and should be individualized by surgeons for their patients' expectations and goals. LEVEL OF EVIDENCE: V.

Prioritising of hip and knee arthroplasty procedures during the COVID-19 pandemic: the European Hip Society and the European Knee Associates Survey of Members.

PURPOSE: During the COVID-19 pandemic there has been a massive reduction of arthroplasty services due to reallocation of hospital resources. The unique challenge for clinicians has been to define which arthroplasty patients most urgently require surgery. The present study aimed to investigate priority arthroplasty procedures during the pandemic and in the reinstatement period from the surgeon's perspective. MATERIAL AND METHODS: An online survey was conducted among members of the European Hip Society (EHS), European Knee Associates (EKA) and other invited orthopaedic arthroplasty surgeons (experts) from across the world. The survey consisted of 17 different arthroplasty procedures/indications of which participants were asked to choose and rank the most important 10. RESULTS: Four hundred and thirty-nine arthroplasty surgeons from 44 countries responded. The EHS and EKA had a 43% response rate of members. In weighted average points, the majority of respondents (67.5 points) ranked 'acute fractures requiring arthroplasty (Periprosthetic fractures, THA/hemi-arthroplasty for femoral neck fractures)' as priority indication number one, followed by 'first-stage explantations for acute PJI (periprosthetic joint infection)' in second place and priority indication (45.9 points) three as 'one-stage revision for acute PJI' (39.7 points). CONCLUSIONS: There was agreement that femoral neck fractures, periprosthetic fractures, and acute infections should be prioritised and cannot be postponed in the setting of the COVID-19 pandemic. As arthroplasty procedures are being resumed in most countries now, there has also been a relaxation of lockdown rules in most countries, which might cause a so-called second wave of the pandemic. Therefore, the results of the current study present a proposal by experts as to which operations should be prioritised in the setting of a second wave of the pandemic.

Good mid-term results with the trident peripheral self-locking cup: a clinical evaluation and migration measurement with EBRA.

INTRODUCTION: The most common cause of failure in total hip arthroplasty (THA) is aseptic loosening. Uncemented cup migration analysis by means of Einzel-Bild-Roentgen-Analyse (EBRA) has shown to be a good predictive indicator for early implant failure if the cup migrates more than 2 mm within 4 years after surgery. In this study, we performed a migration analysis of an uncemented peripheral self-locking (PSL) press-fit cup after 4 years follow-up. MATERIALS AND METHODS: We retrospectively reviewed all patients who received a trident PSL press-fit cup at our department between 2004 and 2017. A total of 636 patients were identified. As inclusion criteria for radiological analysis, a minimum follow-up of 2 years was defined. We reviewed medical histories and performed radiological analysis using EBRA software. EBRA measurements and statistical investigations were performed by two independent investigators. RESULTS: A total of 149 cups in 146 patients (female 82; male 64) met our inclusion criteria. Mean age at surgery was 65 years (33-89). We found a significant improvement in the WOMAC score pre- to postoperative (p < 0.0001). EBRA migration analysis showed a mean total migration of 0.6 mm (0.0-8.2) over our follow-up period of 4 years. Of the investigated cups, 69.8% showed a migration rate smaller than 2 mm in the investigated follow-up. CONCLUSION: The acetabular cup used in our study provides low migration at final follow-up. Therefore, a good long-term outcome can be expected for the PSL cup. TRIAL REGISTRATION: Trial registration number is 20181024-1875 and date of registration is 2018-10-24.

Does the type of surgical approach affect the clinical outcome of total knee arthroplasty?

BACKGROUND: The aim of the study was to investigate the issue of medial midvastus (MMV) vs. medial parapatellar (MPP) approaches in total knee arthroplasty (TKA). It was hypothesized that the two surgical approaches would produce significantly different results with respect to patient-reported knee score outcome (hypothesis 1), short-term postoperative range of motion (ROM) (hypothesis 2), long-term postoperative ROM (hypothesis 3) and prosthesis survival (hypothesis 4). METHODS: A retrospective comparative study design was applied. Data sets were obtained from the state arthroplasty registry. The Western Ontario and McMaster Universities osteoarthritis index (WOMAC) data were analyzed from preoperative and 1 year postoperatively. The ROM data were analyzed for the time points preoperative, postoperative days 4 and 10 and 1 year. RESULTS: Available were 627 cases (407 MMV vs. 220 MPP) and 1 year postoperatively there were no significant differences between groups regarding the WOMAC scores (hypothesis 1). Early postoperatively on days 4 and 10 after TKA there were no differences between groups (p = 0.305 and p = 0.383, respectively, hypothesis 2). Likewise, ROM did not significantly differ between the groups 1 year after TKA (p = 0.338, hypothesis 3). The 5­year prosthesis survival did not differ between the groups and showed 94.46% (95% confidence interval, CI 90.69-96.73%) in the MMV group and 94.33% (95% CI 89.96-96.83%) in the MPP group (p = 0.664, hypothesis 4). CONCLUSION: Both surgical approaches produce equivalent clinical results in terms of early postoperative ROM, late postoperative ROM and 1­year WOMAC. The same prosthesis survival rates can be expected.

Derotational femoral osteotomy changes patella tilt, patella engagement and tibial tuberosity trochlear groove distance.

PURPOSE: The aim was to assess the influence of femoral derotational osteotomy on patella tilt (PT), axial patella engagement (AEI) and tibial tuberosity trochlear groove distance (TTTG). METHODS: Derotational femoral osteotomy was performed on ten lower limbs of body donors embalmed with alcohol-glycerine. Femoral torsion, tibial torsion, knee torsion, PT, AEI and TTTG were evaluated on axial CT slices for an absolute femoral torsion of 15°, 20°, 25°, 30°, 35° and 40°. A linear mixed model analysis was used to estimate the effect of femoral torsion on PT, AEI, TTTG and knee torsion adjusted for correlation due to repeated observations. Estimates with 95% confidence intervals were used to represent the mean change in the dependent variables for one unit of change (degree, mm or AEI) in the predictor variable. RESULTS: A significant correlation was observed between femoral torsion and AEI (p < 0.001), PT (p < 0.001) and TTTG distance (p = 0.002). In cases of increased internal femoral torsion, a significant decreased AEI (estimate - 0.003, 95% CI - 0.003 to - 0.002), an increased PT (estimate 0.3, 95% CI 0.2-0.4) and an increased TTTG distance (estimate 0.1, 95% CI 0.1-0.2) were observed. No correlation was seen between change in femoral torsion and knee torsion (n.s.). CONCLUSIONS: Derotational femoral osteotomy has a significant impact on patella tilt and axial patella engagement. Moreover, TTTG distance is slightly changed by a derotational femoral osteotomy, which has to be taken into account preoperatively when considering surgical procedures. LEVEL OF EVIDENCE: Level V.