Cross-cultural adaptation and validation of the French version of the Hip disability and Osteoarthritis Outcome Score (HOOS) in hip osteoarthritis patients.

OBJECTIVE: To translate and adapt the Hip disability and Osteoarthritis Outcome Score (HOOS) into French and to evaluate the psychometric properties of this new version, by testing feasibility, internal consistency, construct validity, reliability and responsiveness, in patients with hip osteoarthritis (OA). METHODS: The French version of the HOOS was developed according to published international guidelines to ensure content validity. The new version was then evaluated in two symptomatic hip OA populations, one with no indication for joint replacement (medical group), and the other waiting for total hip replacement (THR) (surgery group). The psychometric properties assessed were feasibility: percentage of responses, floor and ceiling effects; internal consistency using Cronbach's alpha; construct validity by evaluating correlations with the Lequesne's index and the visual analogic scale (VAS) for pain (Pearson's correlation coefficient); reliability: intra-class correlation coefficient (ICC), Bland et Altman representation; responsiveness by comparing the results of before and 1 month after injection of hyaluronic acid (medical group) and by comparing the pre and 3 months post THR results (surgery group) by calculating standardized response mean (SRM) and effect size (ES). RESULTS: A total of 88 patients were recruited; 58 in the medicine group (mean age=61.8+/-9 years, range 42-81, 70% women) and 30 in the surgery group (mean age=67.5+/-9 years, range 50-81, 68% women). The percentage of item responses was excellent (99%). Neither a floor nor a ceiling effect was observed, except for a ceiling effect (17.8% of patients with worst possible score) observed prior to surgery in the sport and recreation subscale. The internal consistency was good for four of the five HOOS subscales. As expected, the strongest correlations were observed between all HOOS subscales and Lequesne's index or VAS pain, indicating good construct validity. The reliability was good, with an ICC>0.8 for all subscales. The responsiveness was good for all domains 1 month after hyaluronic acid injection (ES ranging from 0.73 to 1.86 and SRM from 0.51 to 1.04) and high for all domains 3 months after THR (ES ranging from 1.47 to 2.08 and SRM ranging from 1.97 to 3.24). CONCLUSION: The French version of HOOS demonstrated good psychometric properties and appears to be useful for the evaluation of patient-relevant outcome whatever the severity of hip OA. This study provides a basis for the use of this French version of the HOOS in future clinical trials.

Can patients really do sport after TKA?

Function and sport participation was analyzed via a self-administered questionnaire in 347 patients with unilateral noncomplicated TKA. It was 227 women and 120 men with a mean age of 75 (range, 28 to 94) and a mean follow-up of 44 months (range 13-71). Two hundred and thirty-seven patients (68%) reported that their knee was "normal", 56% that their activities were limited by their knee, and 66% that they were as active as they expected to be before the intervention. Of them, 98% were satisfied. Of the patients who were insufficiently active, 52% were not satisfied with their outcome (P < 0.0001). Neither the duration of preoperative pain, the age at evaluation or the number of previous surgeries influenced the subjective result or the degree of patient satisfaction. Among patients under 75 years, 10% regularly participated in strenuous sports but only 13% felt that this ability was important. When participation was analyzed in the motivated patients subgroup, 63% regularly took part in at least one impact sport.

[Infrapatellar fat pad: anterior crossroads of the knee]. / Le corps adipeux infra-patellaire: carrefour antérieur du genou.

The infrapatellar fat pad or Hoffa's fat pad is a cylindrical extrasynovial collection of fat located in the infrapatellar region. Anatomical, biomechanical and imaging data show that the infrapatellar fat pad constitutes a true crossroads between patella, femur and tibia and helps in understanding if not describing regional pathology. Intrinsic lesions (with abnormal signal on MRI) such as hoffitis, anterolateral impingement, plica syndrome, post-arthroscopic changes, trauma, patellar dislocation and extrasynovial tumors are less frequent. On the other hand, extrinsic lesions are more frequent and may affect the synovium, patellar ligament, vascular structures, and bursae. Mucoid and parameniscal cysts may develop in the infrapatellar fat pad. In this article, the anatomical and imaging features of the infrapatellar fat pad will be summarized and the most common lesions will be illustrated.

Antibiotic-loaded tantalum may serve as an antimicrobial delivery agent.

AIMS: The aims of this study were to compare the mean duration of antibiotic release and the mean zone of inhibition between vancomycin-loaded porous tantalum cylinders and antibiotic-loaded bone cement at intervals, and to evaluate potential intrinsic antimicrobial properties of tantalum in an in vitro medium environment against methicillin-sensitive Staphylococcus aureus (MSSA). MATERIALS AND METHODS: Ten porous tantalum cylinders and ten cylinders of cement were used. The tantalum cylinders were impregnated with vancomycin, which was also added during preparation of the cylinders of cement. The cylinders were then placed on agar plates inoculated with MSSA. The diameter of the inhibition zone was measured each day, and the cylinders were transferred to a new inoculated plate. Inhibition zones were measured with a Vernier caliper and using an automated computed evaluation, and the intra- and interobserver reproducibility were measured. The mean inhibition zones between the two groups were compared with Wilcoxon's test. RESULTS: MSSA was inhibited for 12 days by the tantalum cylinders and for nine days by the cement cylinders. At day one, the mean zone of inhibition was 28.6 mm for the tantalum and 19.8 mm for the cement group (p < 0.001). At day ten, the mean zone of inhibition was 3.8 mm for the tantalum and 0 mm for the cement group (p < 0.001). The porous tantalum cylinders soaked only with phosphate buffered solution showed no zone of inhibition. CONCLUSION: Compared with cement, tantalum could release antibiotics for longer. Further studies should assess the advantages of using antibiotic-loaded porous tantalum implants at revision arthroplasty. Cite this article: Bone Joint J 2019;101-B:848-851.

Primary total knee arthroplasty for acute fracture around the knee.

Relatively poor results have been reported with open reduction and internal fixation of complex fractures around the knee in elderly osteoporotic patients, and primary total knee arthroplasty (TKA) has been proposed as an alternative solution. While limiting the number of procedures, it meets two prerequisites: (1) to save the patient's life, thanks to early weight-bearing, to limit decubitus complications; and (2) to save knee function and patient autonomy, thanks to early knee mobilization. There are 3 main indications: complex articular fractures in elderly patients with symptomatic osteoarthritis prior to fracture; complex articular fractures of the tibial plateau in elderly patients whose bone quality makes internal fixation hazardous; and major destruction of the distal femur in younger patients. Although admitted in emergency, these patients require adequate preoperative management, including a multidisciplinary approach to manage comorbidities, control of anemia and pain, and assessment and management of vascular and cutaneous conditions. Preoperative planning is crucial, to order appropriate implants and materials that may be needed intraoperatively. Surgical technique is based on the basic principles of revision surgery as regards choice of implant, steps of reconstruction, bone defect management and implant fixation. For complex fractures of the distal femur, primary temporary reduction is a useful "trick", to determine the level of the joint line and femoral rotation. Complementary internal fixation may be required in case of diaphyseal extension of the fracture and to prevent inter-prosthetic fractures. In the literature, the results of primary TKA for fracture are encouraging and better than for secondary TKA after failure of non-operative treatment or internal fixation, with lower rates of revision and complications, earlier full weight-bearing and better functional results. Loss of autonomy is, however, frequent, and 1-year mortality is high, especially following complex femoral fractures in the elderly.

Influence of treatment modality on morbidity and mortality in periprosthetic femoral fracture. A comparative study of 71 fractures treated by internal fixation or femoral implant revision.

INTRODUCTION: The incidence of periprosthetic femoral fracture is constantly increasing, with high associated morbidity and mortality. Surgical treatment is guided by the Vancouver classification, but the influence of type of treatment on morbidity and mortality has been little analyzed. The theoretical advantage of implant revision over internal fixation is that it should allow earlier weight-bearing, although the impact of this on morbidity and mortality and autonomy has not been demonstrated. We conducted a case-control study, to assess the influence of type of treatment (implant revision or internal fixation) (1) on mobility and autonomy and (2) on morbidity and mortality. HYPOTHESIS: The study hypothesis was that clinical results and morbidity and mortality do not differ between these two types of treatment. METHODS: A retrospective study included 70 patients with a total of 71 femoral periprosthetic fractures treated between 2007 and 2014. Two treatment groups, comparable for mean age, gender and ASA and Parker scores, were studied. Mean age was 78±13.5years (range, 23-95years). Thirty-six fractures (50.7%) were treated by implant revision via a posterolateral approach, using a revision stem with (n=11) or without cement (n=25) (REVISION group); immediate postoperative weight-bearing was authorized. Thirty-five fractures (49.3%) were treated by open reduction and internal fixation, using a locking plate (ORIF group); weight-bearing was authorized only in the third month. Mean follow-up was 43±27months (range, 0.75-107months). RESULTS: Autonomy on Parker score was reduced by 2 points at 1year's follow-up. Mean preoperative scores were 7.32±1.79 (range, 3-9) and 7.43±1.79 (range, 4-9) in the REVISION and ORIF group, respectively, (p=0.8), falling to 5.06±2.6 (range, 0-9) and 4.5±2.01 (range, 0-9) respectively at follow-up (p=0.349). Sixteen patients in the REVISION group versus 13 in the ORIF group had made adaptations in their home or changed place of residence (p=0.2). At last follow-up, 18 patients (28.6%) had died: 12 (37.5%) in the ORIF and 6 (19.3%) in the REVISION group (p<0.05). Survival with death as endpoint at a mean 3.5years was 88±11% in the REVISION group versus 51±11% in the ORIF group (p=0.02). Three implant replacements were performed in each group (p=0.83). Twelve medical or surgical complications occurred in the ORIF group (37.5%) and 11 in the REVISION group (34%) (p=0.9). CONCLUSION: Implant revision for periprosthetic femoral fracture showed significantly lower overall mortality than internal fixation, without difference in terms of treatment failure or complications requiring revision surgery. LEVEL OF EVIDENCE: Level III, case-control study.

Differences in trochlear parameters between native and prosthetic kinematically or mechanically aligned knees.

INTRODUCTION: Kinematic (KA) and mechanical (MA) alignment techniques are two different philosophies of implant positioning that use the same TKA implants. This might generate differences in the resulting prosthetic trochleae parameters between the two techniques of alignment. Our study aim was to test the following hypotheses : (1) mechanically or kinematically aligned femoral implant understuffs the native trochlear articular surface and poorly restores the native groove orientation, and (2) the orientation of the prosthetic trochlear groove and trochlear fill are different between MA and KA. METHODS: Three-dimensional models of the femur were made from segmentation of preoperative Magnetic Resonance Imaging scans (MRIs) of ten subjects with isolated medial tibiofemoral osteoarthritis. In-house planning and analysis software kinematically and mechanically aligned a modern cruciate retaining femoral component and determined differences in parameters of the trochlear fit between native and prosthetic trochleae, and between KA and MA prosthetic trochleae. RESULTS: The MA prosthetic trochleae did not fill (understuffed) the entire length of the native medial facet and the proximal 70% of the native groove and lateral facet, and oriented the trochleae groove 8° more valgus than native. The KA prosthetic trochleae understuffed the proximal 70% of the native trochleae, and had a groove 6° more valgus than native. The KA trochleae understuffed the medial facet distally and oriented the groove 2° less valgus and 3° more internally rotated than the MA trochleae. CONCLUSION: MA and KA prosthetic trochleae substantially understuff and create a prosthetic groove more valgus compared to native trochlear anatomy, and they also differed between each other regarding trochleae stuffing and groove alignment. Although randomized trials have not shown differences in patellofemoral complications between KA and MA, a femoral component designed specifically for KA that more closely restores the native trochlear anatomy might improve patient reported satisfaction and function. LEVEL OF EVIDENCE: Level 2 controlled laboratory study.

Is anatomic acetabular orientation related to pelvic morphology? CT analysis of 150 healthy pelvises.

BACKGROUND: Links between sagittal spinal alignment and acetabular orientation attract considerable research attention with the goal of optimising prosthetic cup position. However, whether pelvic incidence (PI) is related to anatomic acetabular orientation remains unknown. We therefore conducted a radiological study with the following objectives: to look for correlations between PI and anatomic acetabular parameters; to describe the sacro-pubic angle (SPA), defined by fixed bony pelvic landmarks, and its relations with acetabular anteversion; and to determine whether anatomical parameters (PI and SPA) correlate with demographic characteristics. HYPOTHESIS: PI correlates with anatomical acetabular parameters. MATERIALS AND METHODS: We conducted a computed tomography (CT) study of the pelvises of 150 patients free of degenerative disease. Three parameters were measured: anatomic acetabular orientation in the Lewinnek reference plane, PI, and the SPA subtended by the line connecting the midpoint of the sacral endplate to the pubic symphysis and the anterior pelvic plane. Statistical tests were performed to look for correlations among these parameters. RESULTS: Intra-observer and inter-observer reproducibility was considered highly satisfactory (inter-class correlation coefficient, >86% and >82%, respectively). Mean PI was 58.6°±10.2° (range, 32.8°-97.6°), with no significant differences between genders or across age groups. Mean SPA was 34.7°±5.5° (range, 18.3°-49.8°). Mean anatomic acetabular anteversion (AAA) was greater in females (23.4°; range, 11.5°-34.5°) than in males (20°; range, 7.5°-34.5°) (P<0.001). PI did not correlate with any of the acetabular parameters (PI/AAA, r=0.8 and P=0.33; PI/acetabular inclination on the horizontal, r=-0.96 and P=0.24). SPA correlated significantly with both PI (r=0.33 and P<0.001) and AAA (r=0.33 and P<0.001). DISCUSSION: This CT study of normal pelvises showed that AAA was significantly greater in females and that SPA correlated significantly with both PI and acetabular anteversion. SPA could serve to define the "theoretical" AAA of each individual patient and could thus be incorporated into surgical planning protocols or intra-operative guidance methods for hip replacement surgery. LEVEL OF EVIDENCE: IV, retrospective study with no control group.

Superimposition of maximal stress and necrosis areas at the top of the femoral head in hip aseptic osteonecrosis.

INTRODUCTION: Recent reports described possible mechanical factors in the development and aggravation of osteonecrosis of the femoral head (OFH), but these have yet to be confirmed on dedicated mechanical study. We therefore developed a 3D finite element model based on in-vivo data from patients with incipient OFH, with a view to determining whether the necrosis area was superimposed on the maximal stress area on the femoral head. HYPOTHESIS: The location of the necrosis area is determined by stress on the femoral head. MATERIAL AND METHOD: All patients from the rheumatology department with early stage OFH in our center were investigated. Analysis of CT scans showed stress distribution on the head by 3D finite elements models, enabling determination of necrosis volume within the maximal stress area and of the percentage intersection of necrosis within the stress area (%I n/s: necrosis volume in stress area divided by total stress area volume and multiplied by 100) and of stress within the necrosis area (%I s/n: stress volume in necrosis area divided by total necrosis area volume and multiplied by 100). RESULTS: Nineteen of the 161 patients assessed retrospectively for the period between 2006 and 2015 had incipient unilateral OFH, 10 of whom (4 right, 6 left) had CT scans of sufficient quality for inclusion. Mean age was 52 years (range, 37-81 years). Mean maximal stress was 1.63MPa, mean maximal exported stress volume was 2,236.9 mm3 and mean necrosis volume 6,291.1 mm3. Mean %I n/s was 83% and mean %I s/n 35%, with no significant differences according to gender, age, side or stress volume. There was a strong inverse correlation between necrosis volume and %I s/n (R2=-0.92) and a strong direct correlation between exported stress volume and %I s/n (R2=0.55). %I s/n was greater in small necrosis (<7,000mm3). CONCLUSION: OFH seems to develop within the maximal stress area on the femoral head. The present results need confirmation by larger-scale studies. We consider it essential to take account of these mechanical parameters to reduce failure rates in conservative treatment of OFH. LEVEL OF EVIDENCE: IV.

Ten-year survival and complications of total knee arthroplasty for osteoarthritis secondary to trauma or surgery: A French multicentre study of 263 patients.

BACKGROUND: Previous surgical procedures raise technical challenges in performing total knee arthroplasty (TKA) and may affect TKA outcomes. Survival rates of TKA done after trauma or surgery to the knee have not been accurately determined in large populations. The objectives of this retrospective study in 263 patients with TKA after knee trauma or surgery and a follow-up of 10 years were to assess survival, functional outcomes, and the nature and frequency of complications. HYPOTHESIS: Knee trauma or surgery before TKA increases the risk of complications and decreases implant survival. MATERIAL AND METHODS: Two hundred and sixty-three patients (122 [47%] females and 141 [53%] males) underwent TKA between 2005 and 2009 at nine centres in France. Mean age at surgery was 61 years. The patients had knee osteoarthritis secondary to a fracture (n=66), osteotomy (n=131), or ligament injury (n=66). Mean time from trauma or surgery to TKA was 145 months (range, 72-219 months). RESULTS: Major complications were infection (n=12, 4.5%), skin problems (n=8, 3%), and stiffness (n=8, 3%). Ten-year survival to implant exchange for any reason was 89%±2.8%. Flexion range increased by 2.5°±17° (p=0.02) to a mean of 110° (range, 30° to 140°); extension range increased by 4°±7° (p<0.001) to a mean of -1.19 (range, -20° to 0°). Of the 263 patients, 157 (60%) reported little or no pain at last follow-up. Mean postoperative hip-knee-ankle angle was 179°±3.2° (range, 171°-188°). CONCLUSION: TKA performed after knee injury or surgery carries a risk of specific complications (infection, skin problems, and stiffness) and may have a lower survival rate compared to primary TKA. LEVEL OF EVIDENCE: IV, retrospective cohort study.

Three-dimensional custom-designed cementless femoral stem for osteoarthritis secondary to congenital dislocation of the hip.

A clinical and radiological study was conducted on 97 total hip replacements performed for congenital hip dislocation in 79 patients between 1989 and 1998 using a three-dimensional custom-made cementless stem. The mean age at operation was 48 years (17 to 72) and the mean follow-up was for 123 months (83 to 182). According to the Crowe classification, there were 37 class I, 28 class II, 13 class III and 19 class IV hips. The mean leg lengthening was 25 mm (5 to 58), the mean pre-operative femoral anteversion was 38.6 degrees (2 degrees to 86 degrees ) and the mean correction in the prosthetic neck was -23.6 degrees (-71 degrees to 13 degrees ). The mean Harris hip score improved from 58 (15 to 84) to 93 (40 to 100) points. A revision was required in six hips (6.2%). The overall survival rate was 89.5% (95% confidence interval 89.2 to 89.8) at 13 years when two hips were at risk. This custom-made cementless femoral component, which can be accommodated in the abnormal proximal femur and will correct the anteversion and frontal offset, provided good results without recourse to proximal femoral corrective osteotomy.

[Knee arthrodesis with a double mono-bar external fixators to salvage infected knee arthroplasty: retrospective analysis of 18 knees with mean seven-year follow-up]. / Arthrodèse du genou par double fixateur externe monobarre en contexte infectieux: à propos d'une série de 18 cas avec un recul moyen de 7 ans.

PURPOSE OF THE STUDY: Knee arthrodesis is sometimes the only alternative to amputation in patients with an infected knee prosthesis or in major bone damage with loss of the extensor system. We hypothesized that arthrodesis with a double mono-bar external fixators would be a valid technical solution enabling simple fixation sufficiently rigid to control infection. The main objective of our study was to assess outcome with this technique in terms of fusion. The secondary objective was to check remission of the infection at last follow-up for the infection cases. MATERIAL AND METHODS: Mean follow-up in this retrospective analysis of 18 knee arthroplasties in 17 patients was 85 months. Mean patient age was 65 years. All patients presented destruction of the extensor system associated with infection on a total knee arthroplasty (n=14) or joint destruction (n=4). The first operative stage involved insertion of a temporary external fixator using a lateral bar to align the limb. The infected knee prosthesis was then removed or a spacer was inserted. After avivement of the bone surfaces, compression was applied with an external fixator using an anterior bar. Early weight bearing was encouraged. The lateral fixator was removed at 45 days and the anterior fixator at bone healing. RESULTS: First-intention fusion was achieved in 16 of the 18 knees at mean five months (range 3-8 months). Fusion was achieved in one case after surgical revision using a bone autograft. Nonunion persisted in the other patient. Mean time to removal of the anterior fixator was 7.5 months (range 6-12 months). Remission of infection was noted at last follow-up in all patients with infection. DISCUSSION: This technique provides effective treatment for infected knee prostheses or major joint destruction with loss of the extensor mechanism. Joint fusion limits function but is a better solution than above knee amputation. The rigid fixation achieved with two single-bar fixators positioned perpendicularly enables rapid weight bearing, a capital element for these often bedridden elderly patients with multiple co-morbidities. The essential element for fusion is a solid fixation. The use of external fixators also avoids implanting material in septic tissues. Associated with medical treatment for the infection we have been able to achieve complete remission of infection in all patients who underwent arthrodesis for an infected knee arthroplasty.

[Computer-assisted surgery for acetabular cup positioning in total hip arthroplasty: comparative prospective randomized study]. / Positionnement acétabulaire assisté par ordinateur dans les prothèses totales de hanche: étude prospective comparative randomisée.

PURPOSE OF THE STUDY: Actetabular component malpositioning during total hip arthroplasty (THA) increases the risk of dislocation, reduces the range of motion, and can be the cause of early wear and loosening. There have been numerous reports on the optimal orientation of the acebaular component in THA. Lewinnek et al recommended an abduction angle of 40+/-10 degrees and an anteversion of 15+/-10 degrees for cup alignment in THA. In order to prevent malpostioned hip implants and improve the reproducibility of implant alignment in THA, numerous computer-assisted orthopedic systems have been described, using computed tomography (CT)-base or imageless navigation. Among the imageless systems available, one is based on Bone Morphing technology initially described by Stindel for computer-assisted knee arthroplasty and adapted for THA. The purpose of this study was to compare computer-assisted acetabular component insertion versus free hand placement. MATERIAL AND METHODS: A controlled randomized matched prospective study was performed in two groups of 30 patients. The study was approved by the French Ethics Committee. In the first group, cup positioning was assisted by an imageless computer-assisted orthopedics system based on Bone Morphing(R) (CAOS+ group). In the control group, cup placement was free hand (CAOS- group). The same cementless cup was used in both groups. The same surgeon performed all procedures using an anterolateral approach. Cup anteversion and abduction angles were measured on 3D CT scan reconstructions obtained postoperatively for each patient by an independent observer using a special cup evaluation software. RESULTS: There were 16 males and 14 females in each group, mean age was 62 years (range 24-80) years, and mean body mass index was 25 in each group. Mean additional time of the CAOS procedure was 12 minutes (range 8-20). Intraoperative subjective agreement of the surgeon with the computer guidance system demonstrated a high correlation in 23 cases, a weak correlation in six cases and poor correlation in one case. There were no statistical differences between the CAOS+ and the CAOS- group regarding means of the abduction and anteversion angles, but a significant range of variance, the lowest variations being observed in the CAOS+ group. DISCUSSION: This study has shown the accuracy of cup positioning using a CT-free navigation system in a prospective randomized controlled protocol.

[Acetabular revision for aseptic loosening in total hip arthroplasty using cementless cup and impacted morselized allograft]. / Reprise des descellements acétabulaires aseptiques par cupule non cimentée, vissée et allogreffe morcelée impactée.

PURPOSE OF THE STUDY: Impaction grafting can be used in cementless fixation with morsellized bone, bone graft, and hemispherical cup. The first goal of impaction grafting in revision of total hip arthroplasty is to transform segmental defects into cavitary defects and obtain a full compaction of the graft in order to restore the bone stock. The second goal is to achieve primary stability of the cup. The third goal is to restore the hip center of rotation with a cup anatomically located in the acetabulum. The aim of our study was to evaluate the results of a surgical technique with impacted morsellized bone graft and a cementless press-fit cup for the revision with defect type III according to the AAOS classification. MATERIAL AND METHODS: We performed a retrospective study including 34 hip reconstructions during revision of acetabular aseptic loosening with type III AAOS acetabular defects. All the revisions were performed in the same center by two senior surgeons. Mean age at surgery was 58 years. There were 23 women and 11 men. All reconstructions were performed with a cementless cup and a morsellized impacted bone graft. The analysis of the acetabular defects was done preoperatively according to the AAOS classification. We analyzed postoperatively and at follow-up: position and stability of the acetabular cup, restoration of the hip center and graft integration. RESULTS: Mean follow-up was 6.6 years (range 3-13 years). Complications included three dislocations, two trochaanteric nonunions. Two acetabular components were revised for septic loosening. According to the Kaplan-Meier survival curves, with endpoint criteria defined as acetabular cup removal, survival was 91.3% at 10 years (95CI: 86.3-96.3). The preoperative Harris hip score was 53 points (range 26-86) and at last follow-up 94 (47-100). Concerning the subjective clinical outcome, 96% of patients were satisfied or very satisfied at last follow-up. 100% of cups were considered stable at follow-up and bone integration was good in 100%. The center of rotation was located in anatomic position mediolaterally in 66% and in the craniopodal plane in 44%. DISCUSSION: Restoration of bone stock is one of the main goals during hip reconstruction after aseptic loosening. Clinical experience in our series has shown the reliability of the impacted morsellized bone graft allowing relocation of the center of rotation and good cup stability. Biological fixation of the cup and graft integration seems good at mid-term follow-up. The cup that we used in our series combined the advantages of a press-fit cup and those of a reinforcement ring. The combination of this type of cup with morsellized bone graft seems to be a reliable solution for restoring bone stock, relocating the hip center, and stabilizing the cup in revision total hip arthroplasty with type III acetabular defect according to the AAOS classification.

[A pediatric case of rupture of the brachial artery and radial nerve palsy secondary to proximal humeral exostosis]. / Rupture de l'artère brachiale et paralysie radiale secondaire à une exostose proximale de l'humérus chez une enfant de 14 ans.

Rupture of the brachial artery associated with radial nerve palsy in a context of exostosis of the proximal humerus has not been described to date in the literature. Our patient was a fourteen-year-old girl with a history of violent pain occurring suddenly with no prodrome or triggering factor. The pain was localized at the level of the proximal left humerus. Physical examination revealed the presence of a hematoma and complete motor radial nerve palsy. The diagnosis was not confirmed by computed tomography with contrast injection but was confirmed by magnetic resonance imaging which eliminated malignant transformation of the exostosis. After checking the neurovascular bundles and evacuating the hematoma, treatment consisted in resection of the exostosis and arterial repair with an autologous venous graft. We discuss the diagnostic and therapeutic challenges which present vascular complications due to exostosis.

Alignment options for total knee arthroplasty: A systematic review.

In spite of improvements in implant designs and surgical precision, functional outcomes of mechanically aligned total knee arthroplasty (MA TKA) have plateaued. This suggests probable technical intrinsic limitations that few alternate more anatomical recently promoted surgical techniques are trying to solve. This review aims at (1) classifying the different options to frontally align TKA implants, (2) at comparing their safety and efficacy with the one from MA TKAs, therefore answering the following questions: does alternative techniques to position TKA improve functional outcomes of TKA (question 1)? Is there any pathoanatomy not suitable for kinematic implantation of a TKA (question 2)? A systematic review of the existing literature utilizing PubMed and Google Scholar search engines was performed in February 2017. Only studies published in peer-reviewed journals over the last ten years in either English or French were reviewed. We identified 569 reports, of which 13 met our eligibility criteria. Four alternative techniques to position a TKA are challenging the traditional MA technique: anatomic (AA), adjusted mechanical (aMA), kinematic (KA), and restricted kinematic (rKA) alignment techniques. Regarding osteoarthritic patients with slight to mid constitutional knee frontal deformity, the KA technique enables a faster recovery and generally generates higher functional TKA outcomes than the MA technique. Kinematic alignment for TKA is a new attractive technique for TKA at early to mid-term, but need longer follow-up in order to assess its true value. It is probable that some forms of pathoanatomy might affect longer-term clinical outcomes of KA TKA and make the rKA technique or additional surgical corrections (realignment osteotomy, retinacular ligament reconstruction etc.) relevant for this sub-group of patients. Longer follow-up is needed to define the best indication of each alternative surgical technique for TKA. Level I for question 1 (systematic review of Level I studies), level 4 for question 2.

Ropivacaine alters the mechanical properties of hamstring tendons: In vitro controlled mechanical testing of tendons from living donors.

OBJECTIVE: Intraarticular or periarticular injection of ropivacaine (RI) is an element of current knee surgery practices. The goal of this study was to determine the effects of RI on the mechanical properties of hamstring tendons. We hypothesized that RI would have a detrimental effect on the mechanical properties of periarticular soft tissues METHODS: A tensile test to failure was performed on 120 hamstring tendon segments harvested during ACL reconstruction surgery in 120 patients. Two sets of tensile tests were done. The first evaluated the effect of RI itself on the mechanical properties of tendons: 30 samples were soaked for 1hour in a 2% RI solution and compared to 30 samples soaked in a saline solution (control group). The second evaluated the effect of RI concentration on the mechanical properties of hamstring tendons: 30 samples were soaked for 1hour in a 2% RI solution and 30 samples were soaked in a 7.5% RI solution. RESULTS: In the first test, 29 samples from each group were analyzed as two samples (one in each group) failed at the grip interface. The specimens exposed to 2% RI had lower ultimate tensile strength (Δ=4.4MPa, P=0.001), strain energy (Δ=13MPa, P=0.001) and Young's modulus (Δ=1.6MPa, P=0.02) than the specimens in the control group. There was no significant difference in the strain at failure between groups (Δ=5%, P=0.3). In the second test, one specimen from the 7.5% RI group failed during the preloading and was excluded. There was no significant difference in terms of the load at failure and ultimate tensile stress (Δ=0.45MPa, P=0.6) and strain energy (Δ=0.49MPa, P=0.49) between the two groups. There were significant differences in terms of elongation at failure (Δ=28%, P=0.0003) and Young's modulus (Δ=2.6MPa, P=0.005), with the specimens exposed to 7.5% RI undergoing greater deformation and having a lower Young's modulus. DISCUSSION: While local RI injections are widely performed in clinical practice, the results of this in vitro study point to short-term alterations of the mechanical properties of hamstring tendons. If these results hold in vivo, this could lead to weakness of the soft tissues exposed to this product, particularly the tendons and ligaments around the injection area. LEVEL OF EVIDENCE: Experimental study. Level 1.

Mechanical alignment technique for TKA: Are there intrinsic technical limitations?

BACKGROUND: Mechanically aligned (MA) total knee arthroplasty (TKA) is affected by disappointing functional outcomes in spite of the recent improvements in surgical precision and implant designs. This might suggest the existence of intrinsic technical limitations. Our study aims to compare the prosthetic and native trochlear articular surfaces and to estimate the extent of collateral ligament imbalance, which is technically uncorrectable by collateral ligament release when TKA implants are mechanically aligned. STUDY HYPOTHESIS: Conventional MA technique generates a high rate of prosthetic overstuffing of the distal groove, distal lateral trochlear facet and distal lateral femoral condyle (Hypothesis 1), and technically uncorrectable collateral ligament imbalance (hypothesis 2)? Disregarding the distal femoral joint line obliquity (DFJLO) when performing femoral cuts explains distal lateral femoral prosthetic stuffing and uncorrectable imbalance (hypothesis 3)? METHODS: Twenty patients underwent a conventional MA TKA. Pre-operative MRI-based 3D knee models were generated and MA TKA was simulated. Native and prosthetic trochlear articular surfaces were compared using in-house analysis software. Following the automatic determination by the planning software of the size of the extension and flexion gaps, an algorithm was applied to balance the gaps and the frequency and amplitude of technically uncorrectable knee imbalance were estimated. RESULTS: The conventional MA technique generates a significant slight distal lateral femoral prosthetic overstuffing (mean 0.6mm, 0.8mm, 1.25mm for the most distal lateral facet point, groove, and at the most distal point of lateral femoral condyle, respectively) and a high rate of type 1 and 2 uncorrectable knee imbalance (30% and 40%, respectively). The incidence of distal lateral prosthetic overstuffing (trochlea and condyle) and uncorrectable knee imbalance were strongly to very strongly correlated with the DFJLO (r=0.53 to 0.89). CONCLUSION: Conventional MA technique for TKA generates frequent lateral distal femoral prosthetic overstuffing and technically uncorrectable knee imbalance secondary to disregarding the DFJLO when adjusting the femoral component frontal and axial rotations, respectively. LEVEL OF EVIDENCE: level 4.

Can three-dimensional patient-specific cutting guides be used to achieve optimal correction for high tibial osteotomy? Pilot study.

INTRODUCTION: Treatment of medial tibiofemoral osteoarthritis with a high-tibial osteotomy (HTO) is most effective when the optimal angular correction is achieved. However, conventional instrumentation is limited when multiplanar correction is needed. HYPOTHESIS: Use of patient-specific cutting guides (PSCGs) for HTO provides an accurate correction (difference<2°) relative to the preoperative planning. MATERIALS AND METHODS: Between February 2014 and February 2015, 10 patients (mean age: 46 years [range: 31-59]; grade 1 or 2 osteoarthritis in Ahlbäck's classification) were included prospectively in this reliability and safety study. All patients were operated using the same medial opening-wedge osteotomy technique. Preoperative planning was based on long-leg radiographs and CT scans with 3D reconstruction. The PSGCs were used to align the osteotomy cut and position the screw holes for the plate. The desired correction was achieved in the three planes when the holes on the plate were aligned with the holes drilled based on the PSCG. Preoperatively, the mean HKA angle was 171.9° (range: 166-179°), the mean proximal tibial angle was 87° (86-88°) and the mean tibial slope was 7.8° (1-22°). The postoperative correction was compared to the planned correction using 3D CT scan transformations. Intraoperative and postoperative complications were assessed at a minimum follow-up of 1 year. RESULTS: The procedure was successfully carried out in all patients with the PSCGs. On postoperative long-leg radiographs, the mean HKA was 182.3° (180-185°); on the CT scan, the mean tibial mechanical angle was 94° (90-98°) and the mean tibial slope was 7.1° (4-11°). In 19 out of 20 postoperative HKA and slope measurements, the difference between the planned and achieved correction was <2° based on the 3D analysis of the three planes in space; in the other case, the slope was 13° instead of the planned 10°. The intra-class correlation coefficients between the postoperative and planned parameters were 0.98 [0.92-0.99] for the HKA and 0.96 [0.79-0.99] for the tibial slope. There were no surgical site infections; one patient had a postoperative hematoma that resolved spontaneously. DISCUSSION: The results of this study showed that use of PSCGs in HTO procedures helps to achieve optimal correction in a safe and reliable manner. LEVEL OF EVIDENCE: IV - Prospective cohort study.

Total knee arthroplasty after opening- versus closing-wedge high tibial osteotomy. A 135-case series with minimum 5-year follow-up.

INTRODUCTION: High tibial osteotomy (HTO) is effective in treating isolated medial osteoarthritis of the knee, but subsequent deterioration is inevitable, and total knee arthroplasty (TKA) is then an option. The present study sought to compare TKA following medial opening-wedge HTO (OW-HTO) versus lateral closing-wedge HTO (CW-HTO) in terms of intraoperative data and clinical results. The study hypothesis was that there is no significant difference in clinical results or complications in TKA following OW-HTO or CW-HTO. MATERIAL AND METHOD: A retrospective multicenter (9 centers) study was conducted for the French Society of Orthopedic Surgery and Traumatology (SoFCOT), including 135 TKAs following HTO (58 OW and 77 CW) at a minimum 5 years' follow-up. Mean interval between HTO and TKA was 134 months and was longer in case of CW-HTO (P<0.0001). Mean age at TKA was 65.4 years and older in case of CW-HTO (P=0.021). Tibial slope was greater in case of OW-HTO (P=0.024). Prior to TKA, 55.7% of patients could walk without canes, 98.4% found stairs difficult or impossible and only 19.1% could manage a walking distance greater than 1000m. Mean flexion was 110°; 54.2% of patients showed frontal knee stability and 87.8% sagittal stability; 60.1% had a mechanical axis in varus, without difference according to OW- or CW-HTO. RESULTS: Hardware was almost systematically removed (in 98.5% of cases): in the same step for OW-HTO (P=0.018) or often in 2 steps for CW-HTO. The primary approach was generally re-used (54.2%), but less frequently in the CW-HTO group (P=0.0004). Lateral or medial ligament release was not associated in respectively 78.2% and 79.7% of cases. The TKA implant was usually without stem (87.2%) and was fitted using a conventional technique (74.4%). At a mean 87 months' follow-up, 78.5% of patients could walk without canes, stairs were still difficult or impossible for 67%, and 74.1% could now walk further than 1000m; mean flexion was 110.5°. Overall, 91.5% of patients showed frontal knee stability and 98.2% sagittal stability, without difference according to OW- or CW-HTO. There were 15 complications within 3 months, more often in the OW-HTO group (12.3%) although not significantly, and with no difference in severity. Late complications comprised loosening (5.5%) and infection (3.6%) and were more frequent in the CW-HTO group (12%) (P<0.05). DISCUSSION: The study hypothesis was partially confirmed. The only technical differences concerned hardware removal, often performed in two steps in case of CW-HTO, and TKA approach, which differed from the primary approach in case of CW-HTO. Clinical results were comparable between OW- and CW-HTO, but late complications were more frequent in the CW-HTO group. LEVEL OF EVIDENCE: III; comparative retrospective study.