High inter- and intraindividual differences in medial and lateral posterior tibial slope are not reproduced accurately by conventional TKA alignment techniques.

PURPOSE: The purpose of this study was to describe the medial and lateral posterior tibial slope (MPTS and LPTS) on 3D-CT in a Caucasian population without osteoarthritis. It was hypothesised that standard TKA alignment techniques would not reproduce the anatomy in a high percentage of native knees. METHODS: CT scans of 301 knees [male:female = 192:109; mean age 30.1 ([Formula: see text] 6.1)] were analysed retrospectively. Tibial slope was measured medially and laterally in relation to the mechanical axis of the tibia. The proportion of MPTS and LPTS was calculated, corresponding to the "standard PTS" of 3°-7°. The proportion of knees accurately reproduced with the recommended PTS of 0°-3° for PS and 5°-7° for CR TKA were evaluated. RESULTS: Interindividual mean values of MPTS and LPTS did not differ significantly (mean (range); MPTS: 7.2° ( - 1.0°-19.0°) vs. LPTS: 7.2° ( - 2.4°-17.8°), n.s.). The mean absolute intraindividual difference was 2.9° (0.0°-10.8°). In 40.5% the intraindividual difference between MPTS and LPTS was > 3°. When the standard slope of 3°-7° medial and lateral was considered, only 15% of the knees were covered. The tibial cut for a PS TKA or a CR TKA changes the combined PTS (MPTS + LPTS) in 99.3% and 95.3% of cases, respectively. CONCLUSION: A high interindividual range of MPTS and LPTS as well as considerable intraindividual differences were shown. When implementing the recommended slope values for PS and CR prostheses, changes in native slope must be accepted. Further research is needed to evaluate the impact of altering a patient's native slope on the clinical outcome. LEVEL OF EVIDENCE: IV.

Similar rates of return to sports and BMI reduction regardless of age, gender and preoperative BMI as seen in matched cohort of hypoallergenic and standard Cobalt Chromium medial unicompartmental knee arthroplasty.

PURPOSE: To compare the rate of return to sports and body mass index (BMI) reduction in patients who underwent surgery for unicompartmental knee arthroplasty (UKA) with either Cobalt-Chromium (CoCr) alloy UKA or with hypoallergenic UKA, stratified by age, gender and BMI. METHODS: Two consecutive cohorts of patients with a total of 172 UKA and a minimum 2-year follow-up period were prospectively included in this comparative study. The first cohort consisted of 136 consecutive series of standard Cobalt-Chromium (CoCr Group). The second cohort consisted of 36 consecutive mobile-bearing hypoallergenic Titanium Niobium Nitride UKA, (TiNbN Group). The clinical evaluation was based on the University of California, Los Angeles (UCLA) activity scores and the High-Activity Arthroplasty Score (HAAS) evaluated on the day before surgery (T0) and after a minimum follow-up of 12 months (T1) and 24 months (T2). Radiographic evaluation performed at T2 included the femoral component position in varus/valgus, the tibial component in varus/valgus and the anteroposterior slope. RESULTS: No statistical differences were found between the groups at each follow-up, as shown by the UCLA and HAAS score (n.s.). Both groups showed a statistically significant improvement (p < 0.05) at each follow-up.. Both groups showed a statistically significant BMI reduction between T0 and T2 (p < 0.05). Radiographic analysis revealed no statistical differences between the two groups in terms of the three measures after the final follow-up (n.s.). All the subgroups showed a significant (p < 0.05) rate of return to sport if compared with the preoperative value (T2 versus T0), except for male in TiNbN group. CONCLUSIONS: Both TiNbN and CoCr medial mobile-bearing UKA enabled patients to return to sports after the final follow-up, regardless of age, BMI, gender and metal sensitivity. These findings inform shared decision making and can help to manage patient expectations after surgery, in particular, in active patients with an overt metal allergy, a specific hypoallergenic implant should be considered the gold standard implant in partial knee replacement surgery. LEVEL OF EVIDENCE: Cohort Study, Level III. REGISTRATION: researchregistry6250- www.researchregistry.com .

Patellar height after unicompartmental knee arthroplasty: comparison between fixed and mobile bearing.

PURPOSE: The purpose of this study was to determine the changes in patellar heights by comparing standardised pre- and post-operative radiographs in a consecutive series of patients undergoing unicompartmental knee arthroplasty (UKA) with two different approaches and implant designs [fixed bearing (FB) vs mobile bearing (MB)] and to correlate the patellar heights with clinical outcomes. METHODS: One hundred and seventy-two UKA patients were prospectively enrolled in the study. 75 patients underwent a minimally invasive FB medial UKA (referred to hereinafter as the 'FB group'); 97 patients were treated with a minimally invasive MB medial UKA. The pre-operative and mid-term (1-year) post-operative patellar heights and clinical scores of these groups of patients were compared using the Insall-Salvati (IS) and Caton-Deschamps (CD) indices and the Oxford Knee Score (OKS). RESULTS: No differences were found between the two groups either with regard to the pre-operative data (p > 0.05) or between pre- and post-operative radiographic scores at the time of each follow-up (p > 0.05). Both the groups reported a significant clinical improvement (p<0.05) as did all the sub-groups (p < 0.05). In the MB group, a higher CD index in females was found at the final follow-up stage (p = 0.043) and a higher pre-operative CD index was found in patients with BMI ≥ 28 (p = 0.040). A statistically negative correlation was found between the pre-operative OKS and pre-operative IS index (rho=- 0.165; p=0.031). CONCLUSIONS: Both FB and MB arthroplastys with different surgical approaches did not change the patellar height regardless of the age, gender and BMI at short-medium-term follow-up. The post-operative patellar height seems not to be correlated with the clinical outcomes. A higher pre-operative IS index was correlated with knee pain and function. LEVEL OF EVIDENCE: Level II-prospective comparative study. STUDY REGISTRATION: Researchregistry6433- www.researchregistry.com .

The role of the iliofemoral ligament as a stabilizer of the hip joint.

The purpose of this systematic literature review is to analyse the role of the iliofemoral ligament (ILFL) as a hip joint stabilizer in the current literature.A total of 26 articles were included in the review. The ILFL is the largest hip ligament consisting of two distinct arms and is highly variable, both in its location and overall size, and plays a primary role in hip stability; in the case of hip dislocation, the iliofemoral ligament tear does not heal, resulting in a persistent anterior capsule defect. Clinically, the ILFL is felt to limit external rotation in flexion and both internal and external rotation in extension.The abduction-hyperextension-external rotation (AB-HEER) test is overall the most accurate test to detect ILFL lesions. Injuries of the ILFL could be iatrogenic or a consequence of traumatic hip instability, and can be accurately studied with magnetic resonance imaging. Different arthroscopic and open techniques have been described in order to preserve the ILFL during surgery and, in case of lesions, several procedures with good to excellent results have been reported in the existing literature.The current systematic review, focusing only on the ILFL of the hip, summarizes the existing knowledge on anatomy, imaging and function and contributes to the further understanding of the ILFL, confirming its key role in anterior hip stability. Future studies will have to develop clinical tests to evaluate the functionality and stability of the ILFL. Cite this article: EFORT Open Rev 2021;6:545-555. DOI: 10.1302/2058-5241.6.200112.

Clinical and Radiological Outcomes after Knee Arthroplasty with Patient-Specific versus Off-the-Shelf Knee Implants: A Systematic Review.

Customised, patient-specific implants (PSI) manufactured based on computed tomography data are intended to improve the clinical outcome by restoring more natural knee kinematics as well as providing a better fit and a more precise positioning. The aim of this systematic review is to investigate the effect of these PSI on the clinical and radiological outcome compared to standard, off-the-shelf (OTS) implants. Thirteen comparative studies including a total of 2127 knee implants were identified. No significant differences in clinical outcome assessed with the range of motion, the Knee Society Score (KSS), and the Forgotten Joint Score (FJS-12) were found between PSI and OTS implants. PSI showed fewer outliers from the neutral limb axis and a better implant fit and positioning. Whether these radiological differences lead to long-term advantages in terms of implant survival cannot be answered based on the current data. Patients receiving PSI could be discharged home earlier at the same or at an even lower total cost. The effective overall superiority of PSI has yet to be proven in long-term studies.

Surgical treatment of patellofemoral instability using trochleoplasty or MPFL reconstruction: a systematic review.

PURPOSE: Trochleoplasty and reconstruction of the medial patellofemoral ligament (MPFL) are among the most commonly performed surgical treatments in patients with patellofemoral instability. The primary purpose of the study was to perform a systematic literature review on trochleoplasty in the treatment of patients with patellofemoral instability. The secondary purpose was to compare the outcomes with those seen in patients treated after reconstruction of the MPFL. METHODS: A standardised search on search engines was performed. All observational and experimental studies dealing with trochleoplasty were then obtained and reviewed in a consensus meeting. Fifteen articles out of 1543 were included and analysed using the CASP appraisal scoring system. Twenty-five studies on MPFL reconstruction were obtained for comparison. The clinical and radiological outcomes were statistically analysed. RESULTS: Both treatment groups showed significant improvement in outcomes from pre- to post-operatively. The mean post-operative Kujala and the Lysholm scores significantly increased in both groups when compared to preoperatively (trochleoplasty group: Kujala 61.4-80.8 and Lysholm 55.5-78.5; MPFL group: Kujala 46.9-88.8 and Lysholm 59.9-91.1). Post-operatively a positive apprehension test was found in 20 and 8 % of the trochleoplasty and MPFL groups, respectively. No significant differences in redislocation (2 %) and subluxation (5-6 %) rates were found. CONCLUSIONS: This systematic review showed that both trochleoplasty and MPFL reconstruction are able to deliver good clinical outcomes with stable patellofemoral joints. LEVEL OF EVIDENCE: III.

Metal backed fixed-bearing unicondylar knee arthroplasties using minimal invasive surgery: a promising outcome analysis of 132 cases.

BACKGROUND: Unicondylar knee arthroplasty (UKA) is a well-established treatment for isolated osteoarthritis (OA) of the medial knee compartment. Aim of this retrospective study was to evaluate the early clinical and radiological outcomes of a consecutive series of patients treated with medial metal backed fixed-bearing UKA. Furthermore, the influence of the component orientation on the outcome was analyzed. METHODS: From 09/2006 to 11/2010 106 patients (132 knees; 69 ± 9 years) were treated using a metal backed fixed-bearing UKA with a MIS approach. All patients underwent a standardized clinical and radiological follow-up at 6 weeks, 1, 2 and 5 years. Mean follow-up was 3.4 ± 1.0 years. Two patients (three UKAs) deceased and two patients (two UKAs) were lost to follow-up. Three different survival analyses were performed using three different endpoints defining failure: (a) revision with exchange of any UKA component (b) aseptic loosening and (c), a worst case scenario, where it was assumed that all progressive radiolucencies would lead to aseptic loosening and thus these were additionally counted. Clinical outcome was assessed using the American knee society score (AKS) and the Oxford knee score (OKS). Radiographic analysis was done according to the American Knee Society Evaluation and Scoring System adapted for UKA and correlated with the AKS and OKS. RESULTS: Five UKAs (3.8 %) were revised to total knee arthroplasties (TKAs) after a median of 25 (10-33) months. Five year survival was 95.2, 97.5 and 87.7% for the aforementioned endpoints. At final follow-up the median AKS knee score was 99 (50-100) points and the median AKS function score was 100 (60-100) points. The median OKS was 43 (8-48) points. Clinical outcome was independent of the component orientation. CONCLUSION: Fixed-bearing UKA showed excellent clinical and radiological results at up to 5 years follow-up. Outcome was independent of component orientation.

Can clinical examination cause a Stener lesion in patients with skier's thumb?: a cadaveric study.

Approximately one-third of all injuries of the upper limb and 7% of all injuries in skiing affect the ulnar collateral ligaments of the thumb metacarpophalangeal joint (skier's thumb). In some patients the collateral ligaments are displaced proximally over the adductor aponeurosis, resulting in a so-called Stener lesion. In these cases surgical treatment is indicated. We hypothesized that a Stener lesion could be provoked by clinical stability testing in patients with a skiers thumb and performed a cadaveric study on 10 Thiel fixated cadaver hands. For clinical stability testing, the thumb was manually deviated in radial direction in both 30° flexion and extension of the MP-joint. It was performed with maximum strength by two hand surgeons after sequential detachment of the ulnar collateral ligaments. After every sequence, it was assessed if the clinical stability testing had caused a Stener lesion. All of the 10 cadavers showed identical results while testing the clinical stability. A decreased stability was only found after cutting both parts of the ulnar collateral ligaments. A Stener lesion could not be provoked in any of the cadavers at any time by clinical stability testing. Summarizing our findings we conclude that a proper performed clinical stability testing of the thumb MP joint is a safe maneuver, which does not lead to a Stener lesion in patients with skier's thumb.

Clinical value of combined single photon emission computerized tomography and conventional computer tomography (SPECT/CT) in sports medicine.

Integrated hybrid single photon emission computerized tomography (SPECT)/computer tomography (CT) is a promising new diagnostic imaging modality for orthopedic patients. A high diagnostic yield is available from combining the detection of abnormal bone metabolism with SPECT, to the precise anatomical detail available in high resolution CT. With this review, we endeavor to illustrate the clinical value and future perspectives of SPECT/CT in sports medicine.

Clinical longer-term results after internal fixation of proximal humerus fractures with a locking compression plate (PHILOS).

OBJECTIVES: The aim of this study was to investigate the subjective and objective longer-term outcomes after fracture fixation with the Proximal Humerus InterLocking OSteosynthesis (PHILOS) plate. DESIGN: Minimum 4-year follow-up of a primary prospective cohort study. SETTING: Single university trauma center. PATIENTS/PARTICIPANTS: Sixty-four consecutively collected patients fulfilled the study criteria. Seven patients (11%) were lost to follow-up, resulting in 57 patients (65 ± 14 years). INTERVENTION: Open reduction and internal fixation with the PHILOS® plate. MAIN OUTCOME MEASUREMENTS: Standardized follow-up including functional outcome instruments (eg, Constant Murley score, Disabilities of the Arm, Shoulder and Hand), rate of complications, and secondary surgeries at 6, 12, and no less than 48 months (uni- and multivariate analysis; P < 0.05). RESULTS: At the 4- to 6-year follow-up (median 5 years postinjury), patients on average achieved an 87% range of motion of the injured compared with the uninjured shoulder (eg, 133° ± 40° versus 152° ± 26° abduction). Objective and subjective outcome improved significantly during the overall follow-up, most of all in reoperated and younger patients (65 years and younger) and within the first postinjury year. We observed an overall reoperation rate of 29% and 10 patients (17.5%) demonstrated an insufficient result resulting from pain (greater than 3 visual analog scale) or restricted abduction (less than 90°) at longer-term follow-up. First, the need for revision surgery and, second, increasing age were found to be the most predictive factors for unsatisfactory results. CONCLUSIONS: Fracture fixation with the PHILOS showed good to excellent longer-term results in three fourths of patients with outcome partially still improving after the first postoperative year.

Surgical treatment of complex bicruciate knee ligament injuries in elite athletes: what long-term outcome can we expect?

BACKGROUND: A traumatic knee dislocation represents a serious injury, particularly for athletes who have the highest demands on their knee function. PURPOSE: Our aim was to analyze the long-term outcome and return to sports after traumatic knee dislocation in elite athletes treated surgically according to a standardized treatment protocol and to identify predictive factors for a successful outcome. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A review of hospital medical records yielded 26 elite athletes with a knee dislocation (torn bicruciate ligaments and at least one torn collateral ligament), who had undergone an open complete single-stage reconstruction/primary repair of the cruciates and collateral ligaments including the posterolateral corner from January 1983 to August 2006. Return to sport (start of sport-specific training) was recorded. Return to the former level of sports activity was assessed. At a median follow-up of 8 years (range, 1-23 years), 24 patients (92%) were evaluated for instrumented anterior-posterior laxity (KT-1000 arthrometer) and scored on the visual analog scale (VAS pain, satisfaction), International Knee Documentation Committee form (IKDC), American Knee Society score, and Lysholm and Tegner score. Standard weightbearing and stress radiographs were taken. RESULTS: Seventy-nine percent of patients (n = 19) returned to their previous sport after a median time of 5.5 months (range, 1.5-36 months), with 8 of them returning to preinjury levels. Eight percent had a VAS pain score >3. Thirteen percent of patients showed a flexion deficit >15 degrees , and 8% showed an extension deficit >10 degrees . The mean side-to-side differences for anterior and posterior laxity were 2.3 mm (range, 1-5 mm) and 2.0 mm (range, 2-7 mm), respectively. The total IKDC score was normal in 4, nearly normal in 12, abnormal in 6, and severely abnormal in 2 patients. The median Lysholm score was 91.8 (range, 37-100). The median Tegner score decreased from 9 (range, 7-10) to 7 (range, 2-10). The median American Knee Society score was 190 (range, 162-200). The median radiological anterior-posterior side-to-side differences in 30 degrees and 90 degrees flexion were 1 mm (range, 1-6 mm)/1 mm (range, 0-11 mm) and 1 mm (range, 0-7 mm)/3 mm (range, 0-11 mm), respectively. Patients treated more than 40 days after injury had a poorer outcome on the satisfaction and relative Tegner scores. This group was also less successful in returning to sport compared with patients treated earlier. CONCLUSION: Athletes treated by early, open, complete single-stage reconstruction within 40 days of injury had better outcomes. Although 19 of 24 patients returned to sports with good functional outcomes and ligamentous stability, only 8 of 24 athletes reached their preinjury sports activity level.

Reliability of shoulder abduction strength measure for the Constant-Murley score.

Reports using the Constant-Murley score often lack details regarding how strength measurement was performed, which may have an important impact on the results obtained. A description of the measurement is especially important when patients are unable to adopt the prescribed position of 90 degrees shoulder abduction, leading to invalid or highly discrepant scores. We investigated the influence of shoulder abduction and torso position on strength measurement with special emphasis on intraobserver reliability. Thirty-three healthy volunteers were examined using a handheld dynamometer (Isobex) in 30 degrees , 60 degrees , and 90 degrees abduction with or without stabilization of the torso. A linear correlation between strength measurements in different degrees of abduction was observed, with values at 90 degrees abduction on average 15% lower than at 60 degrees and 45% lower than at 30 degrees . In multivariate analysis, gender and weight had a substantial impact on the strength of individual measurement positions. Intraobserver reliability was related to arm and torso position (intraclass correlation coefficients, 0.71-0.93) and was highest for 90 degrees abduction without torso stabilization. These findings emphasize the importance of standardized torso and arm positions ensuring high reliability when performing the strength measurement of the Constant-Murley score.

Immunohistochemical Characterization of Human Synovial Bursa Cells by Light and Transmission Electron Microscopy: Where do These Cells Come From? / Caracterización Inmunohistoquímica de las Células de la Bolsa Sinovial Humana Através de Microscopías de Luz y Transmisión: ¿De dónde Provienen esas Células?

In the present study human synovial bursa specimens were examined by light and transmission electron microscopy. For light microscopical investigation the bursa tissue was stained with azan, haematoxylin-eosin and monoclonal antibodies (CD14, CD33, CD36, CD68, laminin). For electron microscopical investigation the bursa specimens were fixated with Karnovsky's solution and 1,5% osmium tetroxide (Os0(4)) in water distilled and contrasted with 5% uranylacetate and embedded in Epon®. For the first time the antigenic phenotype was characterized and conclusions were drawn about the origin of the synovial bursa cells. Histologically the bursa was divided in two distinct layers; the intima, which is formed by a lining layer and a lamina propria, and a subintimal layer. The intima consisted of macrophage like (type I) and fibroblast like cells (type II). According to the immunohistochemical staining and the electron microscopy the type I cell seemed to be a bone marrow derived monocyte and the more frequently seen type II cell was derived from subintimal fibroblasts. The intimal bursa cell frequently interdigitated and usually communicated by their filopodia (indirect cell-cell-communication). Neither tight or gap junctions nor desmosomes could be documented. Although there was no evidence for the existence of a basal lamina, a concentration of extracellular matrix components beyond the bursa cells was observed. In our study there was no accumulation of laminin around the bursal cells, but striking was a vascular bundle of the intima subintima border zone, which was positive for laminin and CD68 and separated the intima from the subintima. In our opinion this histological structure plays an important role in the regeneration of the lining cells and acts like a barrier between bursa and blood.

En el presente estudio se examinaron bolsas sinoviales humanas a través de microscopía de luz y electrónica de transmisión. Para la microscopía de luz, el tejido de las bolsas se tiñó con Azan, H-E y anticuerpos monoclonales (CD14, CD33, CD36, CD68, laminina). Para la microscopía electrónica las bolsas fueron fijadas con solución de Karnovsky y tetróxido de osmio al 1,5% (Os04) en agua destilada y contrastada con acetato de uranilo al 5% y embebido en Epon®. En primera instada, el fenotipo antigénico fue caracterizado, concluyéndose acerca del origen de las células que componen la bolsa sinovial. Histológicamente la bolsa fue dividida en dos capas distintas - la íntima - la cual es formada por una capa lineal y una lámina propia, y, una subintima. La íntima consistió en células parecidas a macrófagos (Tipo I) y células semejantes a fibroblastos (Tipo II). De acuerdo a la tinción inmunohistoquímica y a la microscopía electrónica, las células tipo I parecen provenir de la médula ósea derivada de monocitos y el más frecuente tipo celular II fue derivadado de los fibroblastos de la subintima. Frecuentemente las células de la íntima de la bolsa se interdigitaban y usualmente se comunicaban a través de sus prolongaciones (comunicación célula indirecta-célula). No se observaron ni uniones abiertas, ni cerradas, ni desmosomas. Aunque no hubo evidencia de la existencia de una lámina basal, se observó una concentración de componentes de matriz extracelular más allá de las células de la bolsa. No hubo acumulación de laminina alrededor de estas células, pero destacada era una banda vascular de la zona límite entre íntima y subintima, la cual fue positiva para laminina y CD68 la cual separaba la íntima de la subintima. En nuestra opinión esta estructura histológica juega un importante rol en la regeneración de las células lineales y actúa como una barrera entre la bolsa y la sangre.

Internal fixation of unstable proximal humerus fractures with an anatomically preshaped interlocking plate: a clinical and radiologic evaluation.

BACKGROUND: We evaluated the outcome after internal fixation of unstable or displaced proximal humerus fractures with a new fixed-angle implant. METHODS: Prospective consecutive study with a 1-year clinical follow-up in 119 of 137 patients (87%; mean 68 +/- 15 years; 31 two-, 47 three-, and 41 four-part fractures). RESULTS: One year postoperatively, the range of motion of the injured side demonstrated on average four-fifths of the function of the contralateral side. Ninety-five percentage of patients (n = 114) could dress themselves independently with no or only slight restriction. The mean disabilities of the arm, shoulder, and hand score was 21 (range, 0-62). The absolute and relative Constant score significantly (p < 0.001) improved from 56 +/- 18 (75% +/- 21%) at 6 months postoperatively to up to 65 +/- 18 (82% +/- 18%) at 12 months postoperatively. The initial fracture configuration did not have a significant influence on clinical outcome or complications. Twenty-six patients (22%) underwent a reintervention because of a clinical problem or subjective complaint, which led to total or relevant relief of problems in 23 patients (87%). Radiologic follow-up revealed a significant correction of the mean fragment angles (p < 0.001) postoperatively compared with initial postcrash radiographs. The precision of intraoperative reduction had a significant impact on the patient's disabilities of the arm, shoulder, and hand scoring (p = 0.02). A comparison of the last evaluable radiographs with the intraoperative intensifier images revealed a mean loss of reduction over time of