An exploratory study of cell stiffness as a mechanical label-free biomarker across multiple musculoskeletal sarcoma cells.

BACKGROUND: Cancer cells are characterized by changes in cell cytoskeletal architecture and stiffness. Despite advances in understanding the molecular mechanisms of musculoskeletal cancers, the corresponding cellular mechanical properties remain largely unexplored. The aim of this study was to investigate the changes in cellular stiffness and the associated cytoskeleton configuration alterations in various musculoskeletal cancer cells. METHODS: Cell lines from five main sarcoma types of the musculoskeletal system (chondrosarcoma, osteosarcoma, Ewing sarcoma, fibrosarcoma and rhabdomyosarcoma) as well as their healthy cell counterparts (chondrocytes, osteoblasts, mesenchymal stem cells, fibroblasts, skeletal muscle cells) were subjected to cell stiffness measurements via atomic force microscopy (AFM). Biochemical and structural changes of the cytoskeleton (F-actin, ß-tubulin and actin-related protein 2/3) were assessed by means of fluorescence labelling, ELISA and qPCR. RESULTS: While AFM stiffness measurements showed that the majority of cancer cells (osteosarcoma, Ewing sarcoma, fibrosarcoma and rhabdomyosarcoma) were significantly less stiff than their corresponding non-malignant counterparts (p < 0.001), the chondrosarcoma cells were significant stiffer than the chondrocytes (p < 0.001). Microscopically, the distribution of F-actin differed between malignant entities and healthy counterparts: the organisation in well aligned stress fibers was disrupted in cancer cell lines and the proteins was mainly concentrated at the periphery of the cell, whereas ß-tubulin had a predominantly perinuclear localization. While the F-actin content was lower in cancer cells, particularly Ewing sarcoma (p = 0.018) and Fibrosarcoma (p = 0.023), this effect was even more pronounced in the case of ß-tubulin for all cancer-healthy cell duos. Interestingly, chondrosarcoma cells were characterized by a significant upregulation of ß-tubulin gene expression (p = 0.005) and protein amount (p = 0.032). CONCLUSION: Modifications in cellular stiffness, along with structural and compositional cytoskeleton rearrangement, constitute typical features of sarcomas cells, when compared to their healthy counterpart. Notably, whereas a decrease in stiffness is typically a feature of malignant entities, chondrosarcoma cells were stiffer than chondrocytes, with chondrosarcoma cells exhibiting a significantly upregulated ß-tubulin expression. Each Sarcoma entity may have his own cellular-stiffness and cytoskeleton organisation/composition fingerprint, which in turn may be exploited for diagnostic or therapeutic purposes.

The gap height in open wedge high tibial osteotomy is not affected by the starting point of the osteotomy.

INTRODUCTION: In open-wedge high-tibial-osteotomy (OWHTO), most surgeons use a preoperative planning software and realise that they should match the intraoperative alignment correction with the preoperative plan. We aimed to determine whether there is a difference in osteotomy gap height when starting the OWHTO either 3 or 4 cm distal to the joint line. This should help to clarify whether the osteotomy starting point must exactly match the preoperative planning. METHODS: 25 patients with constitutional varus alignment were planned for OWHTO. Long-leg-standing-radiographs and mediCAD-software were used. Osteotomy was planned to a neutral Hip-Knee-Ankle angle (HKA) of 0°. The osteotomy-starting-point was either 3 or 4 cm distal to the medial joint line. The following angles were compared: mechanical medial proximal tibial angle (mMPTA), mechanical lateral distal femoral angle (mLDFA), joint line conversion angle (JCA), mechanical Tibio-Femoral angle (mTFA) or Hip Knee Ankle (HKA) angle. RESULTS: 25 Patients (18 males, 7 females) had a mean age of 62 ± 16.6 years and showed a varus-aligned leg-axis. The HKA was - 5.96 ± 3.02° with a mMPTA of 82.22 ± 1.14°. After osteotomy-planning to a HKA of 0°, the mMPTA was 88.94 ± 3.01°. With a mean wedge height of 8.08 mm when locating the osteotomy 3 cm and a mean wedge height of 8.05 mm when locating the osteotomy 4 cm distal to the joint-line, there was no statistically significant difference (p = 0.7). CONCLUSION: When performing an OWHTO aiming towards the tip of the fibula, the osteotomy starting point does not need to exactly match the planned starting-location of the osteotomy. A starting-point 1 cm more distal or proximal than previously determined through the digital planning does not alter the size of the osteotomy gap needed to produce the desired amount of correction.

Evaluation of modified and newly applied patella height indices in primary total knee arthroplasty.

OBJECTIVE: The aim of this radiological study was to compare several relevant modified and newly applied patella height indices (PHI) in navigated primary total knee arthroplasty (TKA) to determine intra- and interobserver reliability in order to give a recommendation for clinical application in measuring patella height (PH) in primary TKA. MATERIALS AND METHODS: A retrospective data analysis assessing different PHI (modified Insall-Salvati index (mISI), Caton-Deschamps index (mCDI), Blackburne-Peel index (mBPI), Plateau-Patella Angle (mPPA); Miura-Kawaramura index (MKI), Knee-Triangular index (KTI)) on lateral knee radiographs was performed by two blinded observers using the same software three months pre- and postoperatively. Concordance correlation coefficient and Pearson's correlation respectively were determined for intra- and interobserver rating as well as a categorization according to Landis and Koch and Cohen. RESULTS: A total of 337/291 patients of a 5-year period could be analyzed pre-/postoperatively. Excellent postoperative interrater results according to the categorization of Landis and Koch were achieved for the mBPI (Pearson 0.98) > mPPA (0.90) > KTI (0.86), good results for the MKI (0.79) and the mCDI (0.69), and moderate results for the mISI (0.52) with a predominantly strong Cohen correlation in almost all cases. Preoperatively, the mBPI and the KTI were the best interrated PHI. No PH changes could be found postoperatively for the mISI, KTI, MKI, and mPPA. CONCLUSION: The mBPI, the mPPA, and the KTI can be recommended for PH assessment in TKA. The mPPA might be the easiest one to use in a daily clinical set-up.

Outside-in repair technique is effective in traumatic tears of the meniscus in active adults: a systematic review.

PURPOSE: Meniscal injuries are common. Outside-in meniscal repair is one of the techniques advocated for the management of traumatic meniscal tears. This systematic review investigated the outcomes of the outside-in repair technique for the management of traumatic tears of the menisci. The outcomes of interest were to investigate whether PROMs improved and to evaluate the rate of complications. METHODS: Following the 2020 PRISMA statement, in May 2023, PubMed, Web of Science, Google Scholar, and Embase were accessed with no time constraints. All the clinical investigations which reported data on meniscal repair using the outside-in technique were considered for inclusion. Only studies which reported data on acute traumatic meniscal tears in adults were considered. Only studies which reported a minimum of 24 months of follow-up were eligible. RESULTS: Data from 458 patients were extracted. 34% (155 of 458) were women. 65% (297 of 458) of tears involved the medial meniscus. The mean operative time was 52.9 ± 13.6 min. Patients returned to their normal activities at 4.8 ± 0.8 months. At a mean of 67-month follow-up, all PROMs of interest improved: Tegner scale (P = 0.003), Lysholm score (P < 0.0001), International Knee Documentation Committee (P < 0.0001). 5.9% (27 of 458) of repairs were considered failures. Four of 186 (2.2%) patients experienced a re-injury, and 5 of 458 (1.1%) patients required re-operation. CONCLUSION: Meniscal repair using the outside-in technique can be effectively performed to improve the quality of life and the activity level of patients with acute meniscal tears. LEVEL OF EVIDENCE: Level IV.

In closed wedge distal femur osteotomies for correction of valgus malalignment overcorrection of mLDFA should be avoided.

PURPOSE: The purpose of the study was to investigate the influence of the mLDFA (mechanical lateral distal femur angle) as a parameter in varus realignment osteotomies for valgus deformities of the knee. We hypothesized that joint line obliquity with mLDFA > 90° after distal femur osteotomy (DFO) is associated with inferior clinical outcome. METHODS: In a retrospective study, a total of 52 patients with isolated femoral valgus deformities were included in the study. The mean postoperative follow-up was 70.5 (SD 33.3) months (standard deviation SD±33.3). In all patients, a distal femur osteotomy was performed. A clinical examination and survey of questionnaires was conducted with the HSS (Hospital for Special Surgery), LG (Lysholm-Gilquist), and KOOS (Knee Injury and Osteoarthritis Outcome Score) scores. Several radiological parameters were assessed on long-standing x-rays: mechanical tibio-femoral angle (mTFA), mLDFA, mechanical medial proximal tibia angle (mMPTA), joint-line convergence angle (JLCA). The t test was used for normally distributed data. The Mann-Whitney U test was performed in non-normally distributed data. RESULTS: The mLDFA was 84.9° (SD±2.3) preop and changed to 91.9° (SD±3, 22.9) postop. The mTFA (mechanical tibio-femoral angle) was 5.2° (SD±2.9°) preop and - 1.8° (SD±2.9) postop demonstrating a difference of 6.7°. For analysis, the data was divided into two groups based on postop mLDFA. Group 1: mLDFA ≤ 90°; Group 2: > 90°. Postoperatively, a mean mLDFA of 88.6° (SD±1.4°) was measured in group 1 and 93.9° (SD±2.1) in group 2. The change in mLDFA was 4.7° (SD±1.6) in group 1 and 8.4° (SD±2.8) in group 2. Preoperatively, the mTFA was 4.8° (SD±1.9) in group 1 and 5.5° (SD±3.3) in group 2. Postoperatively, the mTFA decreased in group 1 by 4.8° (SD±2.3) to - 0.1° (SD±2.1). In group 2, the mTFA decreased by 8.2° (SD±3.8) to - 2.8° (SD±2.9). Regarding the HSS, group 1 showed a 10.4 points better score than group 2 (p<0.01). Also, regarding the Lysholm, a significant difference of 16.9 points was found (p<0.01). CONCLUSION: Correction of valgus knees using closed wedge DFO leads to good clinical results. A postoperative mLDFA of 85-90° results in superior clinical outcome compared to mLDFA > 90°. Joint-line obliquity should be avoided using double level osteotomy, if needed. LEVEL OF EVIDENCE: III.

Posterior shoulder dislocation with associated reverse Hill-Sachs lesion: clinical outcome 10 years after joint-preserving surgery.

INTRODUCTION: Posterior shoulder dislocation in association with reverse Hill-Sachs lesion is a rather rare injury. Few studies reporting results after joint-preserving surgery in these cases are available. This current study presents the clinical outcomes 10 years postoperatively. MATERIALS AND METHODS: In a prospective case series, we operatively treated 12 consecutive patients (all males) after posterior shoulder dislocation with associated reverse Hill-Sachs lesion using joint-preserving techniques. Patients received surgery in a single center between January 2008 and December 2011. The joint-preserving surgical procedure was chosen depending on the defect size and bone quality. The following outcome-measures were analyzed: Constant-Score, DASH-Score, ROWE-Score, and SF-12. Results 1, 5, and 10 years postoperatively were compared. RESULTS: Out of 12 patients, ten patients (83.3%) were followed-up with a mean follow-up interval of 10.7 years (range 9.3-12.8). The mean patient age at the time of the last follow-up was 51 years (32-66). The outcome scores at the final follow-up were: Constant 92.5 (range 70.0-100), DASH 3.2 (0.0-10.8), ROWE 91.0 (85.0-100), and SF-12 87.8 (77.5-98.3). Clinical results had improved from 1 to 5 years postoperatively and showed a tendency for even further improvement after 10 years. CONCLUSIONS: Joint-preserving surgical therapy of posterior shoulder dislocation provides excellent results when the morphology of the reverse Hill-Sachs lesion is respected in surgical decision-making. TRIAL REGISTRATION: 223/2012BO2, 02 August 2010.

Rotation osteotomy of the distal femur influences coronal femoral alignment and the ischiofemoral space.

INTRODUCTION: Despite the fact that osteotomies around the knee represent well-established treatment options for the redistribution of loads and forces within and around the knee joint, unforeseen effects of these osteotomies on the remaining planes and adjacent joints are still to be defined. It was, therefore, the aim of this study to determine the influence of a distal femoral rotation osteotomy on the coronal limb alignment and on the ischiofemoral space of the hip joint. MATERIALS AND METHODS: Long-leg standing radiographs and CT-based torsional measurements of 27 patients undergoing supracondylar rotational osteotomies of the femur between 2012 and 2019 were obtained and utilized for the purpose of this study. Postoperative radiographs were obtained after union at the osteotomy site. The hip-knee-ankle angle (HKA), the mechanical lateral distal femur angle (mLDFA), and the ischiofemoral space were measured. Comparison between means was performed using the Wilcoxon-Mann-Whitney test. RESULTS: Twenty-seven patients underwent isolated supracondylar external rotation osteotomy to reduce the overall antetorsion of the femur. The osteotomy resulted in a 2.4° ± 1.4° mean increase in HKA and 2.4 mm ± 1.7 mm increase in the ischiofemoral space (p < 0.001). CONCLUSION: Supracondylar external rotation osteotomy of the femur leads to valgisation of the coronal limb alignment and increases the ischiofemoral space. This is resultant to the reorientation of the femoral antecurvature and the femoral neck. When planning a rotational osteotomy of the lower limb, this should be appreciated and may also aid in the decision regarding osteotomy site.

Osteotomies around the knee lead to corresponding frontal realignment of the ankle.

INTRODUCTION: Despite the fact that osteotomies around the knee represent well-established treatment options for the redistribution of loads and forces within and around the knee joint, unforeseen effects of these osteotomies on the ankle are still to be better understood. It was therefore the aim of this study to determine the influence of osteotomies around the knee on the coronal alignment of the ankle. We hypothesize that osteotomies around the knee for correction of genu varum or valgum lead to a change of the ankle orientation in the frontal plane by valgisation or varisation. MATERIALS AND METHODS: Long-leg standing radiographs of 154 consecutive patients undergoing valgisation or varisation osteotomy around the knee in 2017 were obtained and utilized for the purpose of this study. Postoperative radiographs were obtained after union at the osteotomy site. The hip knee ankle angle (HKA), the mechanical lateral distal femur angle (mLDFA), the mechanical medial proximal tibia angle (mMPTA) and five angles around the ankle were measured. Comparison between means was performed using the Wilcoxon-Mann-Whitney test. RESULTS: One hundred fifty-four patients (96 males, 58 females) underwent osteotomies around the knee for coronal realignment. The mean age was 51 ± 11 years. Correction osteotomies consisted of 73 HTO, 54 DFOs, and 27 double level osteotomies. Of all osteotomies, 118 were for valgisation and 36 for varisation. For valgisation osteotomies, the mean HKA changed from 5.8° ± 2.9° preoperatively to - 0.9° ± 2.5° postoperatively, whereas the mMPTA changed from 85.9° ± 2.7° to 90.7° ± 3.1° and the malleolar-horizontal-orientation-angle (MHA) changed from 16.4° ± 4.2° to 10.9° ± 4.2°. For varisation osteotomies, the mean HKA changed from - 4.3° ± 3.7° to 1.1° ± 2.2° postoperatively, whereas the mLDFA changed from 85.7° ± 2.2° to 89.3° ± 2.3° and the MHA changed from 8.8° ± 5.1° to 11.2° ± 3.2°. CONCLUSION: Osteotomies around the knee for correction of coronal limb alignment not only lead to lateralization or medialization of the weight-bearing line at the knee but also lead to a coronal reorientation of the ankle. This can be measured at the ankle using the MHA. When planning an osteotomy around the knee for correction of genu varum or valgum, the ankle should also be appreciated-especially in patients with preexisting deformities, ligament instabilities, or joint degeneration around the ankle.

The ischiofemoral space of the hip is influenced by the frontal knee alignment.

PURPOSE: The ischiofemoral distance (IFD), defined as the distance between the ischial tuberosity and the lesser trochanter of the femur, is gaining recognition as an extra-articular cause of hip pain. It is unknown whether the IFD is influenced by the frontal knee alignment. The aim of this study was to determine the influence of realignment surgery around the knee on the IFD. It was hypothesized that valgisation osteotomy around the knee is associated with reduction of the IFD. METHODS: A consecutive series of 154 patients undergoing frontal realignment procedures around the knee in 2017 were included in this study. Long-leg standing radiographs were obtained before surgery and postoperatively. The IFD was measured between the ischium and the lesser trochanter at three different levels (proximal, middle and distal margins of the lesser trochanter parallel to the horizontal orientation of the pelvis) on standardized long-leg radiographs with the patient in upright standing position. The knee alignment was determined by measuring the hip knee ankle angle, mechanical lateral distal femur angle and the medial mechanical proximal tibia angle. Linear regression was performed to determine the influence of the change of frontal knee alignment on the IFD. RESULTS: Linear regression showed a direct influence of the overall change in frontal knee alignment on the IFD of the hip, regardless of the site of the osteotomy (ß-0.4, confidence-interval - 0.5 to - 0.3, p < 0.001). Valgisation osteotomy around the knee induced a significant reduction of the ipsilateral IFD (p < 0.001), while varisation osteotomy induced a significant increase (p < 0.001). The amount of ISD change was 0.4 mm per corresponding degree of change in frontal knee alignment. CONCLUSION: These findings are relevant to both the hip and knee surgeons when planning an osteotomy or arthroplasty procedure. Correction of a malalignment of the knee may resolve an ischiofemoral conflict in the hip. The concept deserves inclusion in the diagnostic workup of both the hip and knee joints. LEVEL OF EVIDENCE: IV.

Reliability of a Caton-Deschamps-derived patella height index for knee arthroplasty.

PURPOSE: The original Caton-Deschamps index (oCDI) detects functional patella height. It cannot be used in knees with an implanted endoprosthesis. The "modified Caton-Deschamps index" (mCDI) for knee arthroplasty can miss pseudo-patella-infera (PPI), which is common after TKA. A derivate of the oCDI could be a simple analogue to the index published in 1982 using a modified tibial reference point at the anterior proximal point of the inlay, which can indirectly be located on the lateral knee radiograph. It was the aim of this study to determine the intra- and inter-rater agreement of a derived Caton-Deschamps index (dCDI) for knee arthroplasty. We hypothesized that the derived Caton-Deschamps index (dCDI) is a reliable radiological measure for patella height in knee arthroplasty. METHODS: Several patella height indices were measured by three independent raters in two passes. The second pass was performed after 6 weeks in random order. Intra- and inter-observer agreements were determined and analyzed using the intraclass correlation coefficient (ICC). For radiographic evaluation, digital lateral radiographs of 150 knees before and after primary TKA were used. RESULTS: We found high interrater reliability for all analyzed indices. We found the highest agreements for the ISI preop (ICC = 0.914) and postop (ICC = 0.920), respectively. We also found very good intra-rater reliability for the CDI (ICCpreop = 0.954), dCDI (ICCpostop = 0.945), ISI (ICCpreop = 0.960; ICCpostop=0.940) and BPI (ICCpreop = 0.969; ICCpostop = 0.955). Fourteen cases (9.3%) with insignificant PPI were found. CONCLUSION: The derived Caton-Deschamps index (dCDI) can easily be used in knee arthroplasty and demonstrated high intra- and interrater agreement, which was similar to other commonly used and established patella height indices.

Long-term outcome of anterior cruciate ligament tear without reconstruction: a longitudinal prospective study.

PURPOSE: To analyse subjective and objective long-term outcomes of patients with anterior cruciate ligament (ACL)-deficient knees and limited demands regarding sportive activities. This subgroup of patients might be well-treated without ligament reconstruction. METHODS: We included 303 patients with unilateral tears of the ACL and conservative treatment into a prospective study. Mean age at injury was 33.8 (min. 18, max. 66) years. Follow-up was 27.1 (min. 21.3, max. 31.5) years. Follow-up examinations were conducted 12 and 27 years after injury. At the last follow-up we analysed 50 patients completely. To evaluate clinical and radiological outcomes we used the Lysholm score, Tegner activity scale, visual analogue scale for pain (VAS-pain), KOOS and Sherman score. RESULTS: Subjective outcome (Lysholm score and VAS-pain scale) improved between the 12th and 27th year after anterior cruciate ligament tear. At the same time activity level (Tegner activity scale) decreased. Also, arthritis (Sherman score) worsened over time. Twenty-seven years after injury, 90 % of the patients rated their ACL-deficient knee as normal or almost normal; 10 % of the patients rated it as abnormal. The findings of this study show that there is a subgroup of patients with ACL tears who are well treated with physiotherapy alone, not reconstructing the ligament. Also, other authors found this correlation between activity level reduction and better subjective outcome. CONCLUSIONS: Conservative treatment of an ACL tear is a good treatment option for patients with limited demands regarding activity. Patient age, sportive activities and foremost subjective instability symptoms in daily life should be considered when deciding for or against ACL reconstruction.

Similar outcomes between two-stage revisions for infection and aseptic hip revisions.

PURPOSE: Two-stage revision hip arthroplasty using an antibiotic-loaded spacer is the most widely performed procedure for infected hip arthroplasties. The clinical outcome of this type of surgery compared with aseptic joint revision with exchange of femoral and acetabular components is still controversial due to the relative lack of medium- to long-term follow-up. Therefore, we analysed clinical and radiological outcomes of septic two-stage revisions compared with aseptic hip revision surgeries. METHODS: In this retrospective study we assessed 82 consecutive patients who underwent two-stage revision for septic total hip (45 patients) or one-stage aseptic revision arthroplasty (37 patients). The average follow-up was 53 months for the aseptic group and 55 months for the septic group. For clinical evaluation, we used the Harris Hip Score (HHS) and the Merle d'Aubigné and Postel score. The postoperative pain level was determined with the visual analogue pain scale. RESULTS: The surgeries were performed 124 months (aseptic group) and 119 months (septic group) after primary total hip arthroplasty on average. The main indications for aseptic revision surgeries were aseptic loosening (96%), dislocation (2.2%), and periprosthetic fracture (2.2%). In the clinical outcome patients achieved 75.5 points in the aseptic group and 73.4 points in the septic group in the Harris Hip Score. The Merle d'Aubigné and Postel Score revealed 12.5 points for the aseptic group and 13.1 points for the septic group. Mean level of persisting pain was 0.8 (aseptic group) and 0.4 (septic group) on the visual analogue scale (VAS). Overall survival in the aseptic group was 85.6% at 9.8 years 82.7% at 10.1 years for the septic group, with a repeat revision rate of 8.1% and 6.7%, respectively. CONCLUSIONS: Performing aseptic acetabular and femoral revision hip arthroplasty showed equal clinical outcomes in relation to septic two-stage revision hip surgeries. Our results showed a tendency for better outcome in comparison with the information given in the literature for septic and nonseptic exchange arthroplasties, including a lower rate of re-revisions.

No significant difference in clinical outcome and knee stability between patellar tendon and semitendinosus tendon in anterior cruciate ligament reconstruction.

INTRODUCTION: ACL reconstruction with either patellar tendon or semitendinosus tendon autografts are standard procedures. Between these two grafts might be differences in stability, morbidity, or long-term changes. This study investigates outcomes of ACL reconstruction with patellar tendon versus semitendinosus tendon autografts. We hypothesize no significant differences in clinical outcome and knee stability between both groups. METHODS: In a randomized prospective trial, we operated 62 ACL-deficient patients, 45 males and 17 females with a mean age of 29.8 years (min. 18, max. 44). We reconstructed the ligament using either autologous patellar tendon (n = 31) or semitendinosus tendon (n = 31). After 10 years of follow-up, we investigated 47 patients of the study. For evaluation we used a standard clinical examination including one-leg jump test and KT-1000 instrumental translation measure, visual analog pain scale, IKDC subjective knee form, Lysholm score, Tegner activity scale, and standard X-rays of the knee. RESULTS: The data did not show any significant differences between the two groups. Between 5 and 10 years after ACL reconstruction both groups started to develop degenerative arthritic changes, which were detectable in standard radiographs of the knee. At 10-year follow-up mean IKDC for the BPTB group was 1.8 (min. 1, max. 3) and for the ST group it was 2.2 (min 1, max. 4), p = 0.35. Regarding Tegner activity scale after 10 years, the BPTB group showed a mean score of 5.9 (min. 4, max. 9) versus 5.1 (min. 3, max. 7) in the ST group, p = 0.53. For the Lysholm score the BPTB group reached a mean of 92.0 (min. 63, max. 98) and the ST group 91.8 (min. 62, max. 98) points, p = 0.66. There is a tendency for higher donor site morbidity in the BPTB group than in the ST group, p = 0.07. CONCLUSIONS: Both, patellar tendon and semitendinosus tendon are safe autografts for ACL reconstruction. Regarding graft selection, individual patient-dependent factors should be considered. ACL reconstruction cannot fully restore pre-injury status of knee joint function in the majority of cases.

Outcome of isolated polyethylene tibial insert exchange after primary cemented total knee arthroplasty.

PURPOSE: Total knee arthroplasty using a modular design gives the possibility for an isolated exchange of the tibial polyethylene insert in patients with failed total knee arthroplasty. The success of this kind of surgery is still controversial. We analysed the clinical outcome after isolated tibial polyethylene insert exchange. METHODS: In this retrospective study we included 62 consecutive patients with an isolated tibial polyethylene insert exchange at our institution. The average follow-up was 35 months. For clinical evaluation we used the Oxford Knee score, the Knee Society score, the Turba score, and the Kujala score. The health-related quality of life was determined with the SF-36 score and the visual analogue pain scale. RESULTS: The operations were performed 73 months after primary total knee arthroplasty on average. The main reasons for isolated tibial polyethylene insert exchange were instability and wear. In the clinical outcome patients achieved 31.5 points in the Oxford Knee score, 120.5 points in the Knee Society score, 9.3 points in the Turba score, and 49.0 points in the Kujala score. Mean level of persisting pain was 2.2. In the SF-36 score patients achieved 36.3 points physical and 51.7 points mental. The overall survival for isolated tibial insert exchange revealed 72.2 % survival at 6.25 years follow-up with a repeat revision rate of 11 %. CONCLUSIONS: Isolated tibial polyethylene insert exchange revealed a good clinical outcome. There is a tendency for better results in comparison with the information given in literature for most of the parameters including a lower rate in repeat revision.

Outcome of a modular tapered uncemented titanium femoral stem in revision hip arthroplasty.

PURPOSE: Revision hip arthroplasty using a modular tapered design gives the possibility for customising the prostheses to the individual anatomy intra-operatively. The success of this kind of surgery is still controversial due to the relative lack of medium- to long-term follow-up. Therefore we analysed the clinical and radiological outcome of the modular MRP-TITAN stem with diaphyseal fixation in revision hip surgery. METHODS: In this retrospective study we included 136 consecutive patients with MRP-TITAN stem implanted during revision hip arthroplasty. The average follow-up was 55 months. For clinical evaluation we used the Harris Hip Score and the Merle d'Aubigné and Postel score. The health-related quality of life was determined with the visual analogue pain scale. RESULTS: The surgeries were performed 109 months after primary total hip arthroplasty on average. The main indications for the MRP-TITAN revision stem were aseptic loosening, infection, and periprosthetic fracture. In the clinical outcome, patients achieved 75.1 points in the Harris Hip Score and 14.4 points in the Merle d'Aubigné and Postel Score. Mean level of persisting pain was 0.7 (VAS). The overall survival of the MRP stem in revision hip arthroplasty revealed 85.6% survival at 9.75 years' follow-up with a repeat revision rate of 6.8%. CONCLUSIONS: Performing revision hip arthroplasty using the MRP-TITAN stem revealed a good clinical outcome. There is a tendency for better results in comparison with the information given in literature for cementless modular revision stems including a lower rate in re-revisions.

Outcome of a modular head-neck adapter system in revision hip arthroplasty.

PURPOSE: Revision hip arthroplasty using a modular head-neck adapter gives the possibility of keeping a well-fixed femoral component while revising the acetabular prosthesis or femoral head and adapt leg length and femoral offset to the individual anatomy intraoperatively. The success of this kind of surgery is still unclear due to the lack of medium- to long-term follow-up. Therefore, we analyzed the clinical and radiological outcome of the modular Merete BioBall© adapter system in revision hip surgery. METHODS: In this retrospective study, we included 95 consecutive patients with a Merete BioBall© adapter system implanted during revision hip arthroplasty. The average follow-up was 52.5 months. For clinical evaluation, we used the Harris Hip Score. The health-related quality of life was determined with the visual analog pain scale. RESULTS: The surgeries were performed 97 months after prior hip arthroplasty on average. The main indications for the Merete BioBall© adapter system were dislocation, acetabular loosening, and wear. In the clinical outcome, patients achieved 80.9 points in the Harris Hip Score. The mean level of persisting pain was 1.4 (VAS). The overall survival of the Merete BioBall© system in revision hip arthroplasty revealed 92.8 % survival at 8.17 years follow-up with a repeat revision rate of 5.2 %. CONCLUSIONS: Performing revision hip arthroplasty using the Merete BioBall

Classification and Incidence of Heterotopic Ossifications in Relation to NSAID Prophylaxis after Elbow Trauma.

Heterotopic ossification (HO) after elbow trauma can be responsible for significant motion restrictions. The study's primary aim was to develop a new X-ray-based classification for HO of the elbow. This retrospective study analyzed elbow injury radiographs from 138 patients aged 6-85 years (mean 45.9 ± 18) who underwent operative treatment. The new classification was applied at 6 weeks, 12 weeks, and 6 months postoperatively. The severity of HO was graded from 0 to 4 and localization was defined as r (radial), p (posterior), u (ulnar) or a (anterior) by two observers. The patients were categorized based on injury location and use of non-steroidal anti-inflammatory drugs (NSAIDs) for HO prophylaxis. The correlations between the generated data sets were analyzed using Chi-square tests (χ2) with a significance level of p < 0.05. The inter- and intraobserver reliability was assessed using Cohen's Kappa. In 50.7% of the evaluated X-rays, the formation of HO could be detected after 12 weeks, and in 60% after 6 months. The analysis showed a significant correlation between the injury's location and the HO's location after 12 weeks (p = 0.003). The use of an NSAID prophylaxis did not show a significant correlation with the severity of HO. The classification showed nearly perfect inter- (κ = 0.951, p < 0.001) and intrareliability (κ = 0.946, p < 0.001) according to the criteria of Landis and Koch. Based on the presented classification, the dimension and localization of HO in the X-ray image can be described in more detail compared to previously established classifications and, thus, can increase the comparability of results across studies.

Ankle fractures of the geriatric patient: a narrative review.

The present narrative review provides a summary of current concepts for the treatment of ankle fractures in elderly patients. Despite a high complication rate, open reduction and internal fixation is the gold standard for operative care. However, individual patient-based treatment decision considering the soft-tissue status, the fracture pattern, as well as the patient's mobility and comorbidities is mandatory to achieve sufficient patient outcomes. Due to high complication rates after surgery in the past, techniques such as fibular nails or minimal invasive techniques should be considered.

Risk factors for liner wear and head migration in total hip arthroplasty: a systematic review.

Total hip arthroplasty (THA) is a successful orthopaedic surgical procedure, and its longevity depends on bearing components and implant fixation. Optimizing polyethylene and ceramics has led to improved wear parameters and contributed to improved long-term outcomes. The present systematic review investigated whether time span from implantation, patient characteristics and performance status exert an influence on liner wear and head migration in THA. This study was conducted in conformity to the 2020 PRISMA guidelines. All the clinical investigations which reported quantitative data on the amount of liner wear and head migration in THA were considered. Only studies which reported quantitative data at least on one of the following patient characteristics were suitable: mean age, mean BMI (kg/m2), sex, side, time span between the index THA and the last follow-up (months) were eligible. A multiple linear model regression analysis was employed to verify the association between patient characteristics and the amount of liner wear and/or head migration. The Pearson Product-Moment Correlation Coefficient was used to assess the association between variables. Data from 12,629 patients were considered. The mean length of the follow-up was 90.5 ± 50.9 months. The mean age of patients at surgery was 58.4 ± 9.4 years, and the mean BMI was 27.2 ± 2.5 kg/m2. 57% (7199 of 12,629 patients) were women, and in 44% (5557 of 12,629 patients) THAs were performed on the left. The mean pre-operative Harris hip score was 46.5 ± 6.0 points. There was evidence of a moderate positive association between the amount of liner wear and the time elapsed between the index surgery to the follow-up (P = 0.02). There was evidence of a moderate positive association between the amount of head migration and the time elapsed between the index surgery to the follow-up (P = 0.01). No further statistically significant association was found. The time elapsed between the index surgery to the follow-up was the most important factor which influence the head migration and liner wear in THA. Patients' characteristics and preoperative physical activity did not influence the amount of head migration and liner wear.

The Female Pelvis Is Associated with a Lateralized Ischium and a Reduced Ischiofemoral Space.

BACKGROUND: Pelvi-femoral conflicts are increasingly recognized for their explanatory role in the pathology of extra-articular hip impingement. Ischiofemoral impingement (IFI) is a type of impingement between the femur and the ischium that causes high femoral antetorsion and valgus femoral neck orientation. It is unknown whether obstetric adaptation of the female pelvis renders the female hip at a higher risk of sustaining IFI. The aim of this study was to determine the influence of the pelvic morphology on the ischiofemoral space (IFS). METHODS: Plain radiographs of healthy individuals with no symptomatic hip disease were obtained in a functional standing position in a standardized manner and utilized for measurement of the interischial and ischiofemoral widths, subpubic angle, and centrum collum diaphyseal (CCD) angle. Linear regression was performed to determine the influence of morphometric measures on the ischiofemoral space. RESULTS: Sixty-five radiographs (34 females and 31 males) were included. The cohort was stratified according to gender. Significant gender-related differences were noted regarding the ischiofemoral distance (31% increase in males, p < 0.001), pubic-arc angle (30% increased in females, p < 0.001), and the interischial space (7% increase in females, p < 0.001). CCD did not significantly differ between genders (p = 0.2). Factors influencing the IFS include the pubic-arc angle (ß = -0.01 (CI -0.02--0.00), p = 0.003), interischial distance (ß = -0.11 (CI -0.23--0.00), p = 0.049) and CCD (ß = -0.06 (CI -0.09--0.04), p < 0.001). CONCLUSIONS: Obstetric adaptation is associated with an increased subpubic angle that shifts the ischia laterally and away from the symphysis. The resultant reduction in the ischiofemoral space renders the female pelvis at a higher risk for a pelvi-femoral conflict, or more precisely, an ischiofemoral conflict, due to the reduced ischiofemoral space of the hip. The CCD angle of the femur was shown not to be gender specific. However, the CCD angle demonstrates an influence on the ischiofemoral space, rendering the proximal femur a target for corresponding osteotomies.