Dedicated locking plate reduces non-union risk in open ankle fusion in obese patients.

INTRODUCTION: Obesity is a growing public health concern. In ankle osteoarthritis, non-conservative treatment in advanced stages consists in ankle fusion, or else total ankle replacement, for which obesity is a relative contraindication. One of main complications of ankle fusion is non-union. Devascularization, obesity and fixation material are all factors involved in postoperative non-union, and have to be taken into account in surgical strategy for reliable results. The objective of this study was to compare the rate of ankle non-union in obese patients using quadruple screwing or a dedicated locking plate. The hypothesis was that the locking plate limits the risk of non-union in this population. METHODS: All patients were obese (BMI>30kg/m2) and presented ankle osteoarthritis with>10° intra-articular deformity. The approach and joint preparation were performed via an anteromedial approach. Group S was composed of 32 patients, operated on by quadruple screwing; group P comprised 10 patients operated on using a dedicated locking plate. The main endpoint was a significant difference in the rate of non-union between the 2 groups. The secondary endpoint was improvement in pre- and 6-month postoperative AOFAS score. RESULTS: Group S presented 31% non-union (10/32) and group P 0% (0/10) (p<0.05). Postoperative AOFAS score was significantly higher in group P: 67.8±10.4 [range, 40-92] vs. 83.1±8.0 [range, 64-92] (p<0.05). CONCLUSION: The dedicated anterior locking plate is a technique of choice for ankle fusion in obese patients with intra-articular deformity>10°, to limit the risk of non-union. LEVEL OF EVIDENCE: IV; retrospective study.

Better Constant Scores and Active Forward Elevation Using Deltopectoral Versus Anterosuperior Approach for Reverse Shoulder Arthroplasty: Matched Cohort Study.

Purpose: To determine, from a sizable cohort of reverse shoulder arthroplasty (RSA), whether the deltopectoral (DP) or anterosuperior (AS) approach grant better outcomes at a minimum follow-up of 24 months. Methods: The authors reviewed 743 RSAs in patients with primary osteoarthritis (OA) with or without rotator cuff lesions and secondary OA due to rotator cuff tears. The DP approach was used in 540 and the AS approach in 203. Pre- and post-operative constant scores (CSs) and shoulder range of motion were recorded. Results: Of the initial cohort of 743 shoulders, 193 (25.7%) were lost to follow-up, 16 (2.1%) died, and 33 (4.4%) were revised; 540 shoulders were operated using DP approach (73%), of which 22 were revised (4.1%), while 203 were operated using the AS approach (27%), of which 11 were revised (5.4%). Propensity score matching resulted in two groups: 172 shoulders operated by DP approach, and 88 shoulders operated by AS approach. Comparing outcomes of the matched groups at 2 or more years also revealed that, compared to the AS approach, the DP approach resulted in significantly better post-operative CSs (67.3 ± 14.0° vs 60.8 ± 18.3, P = 0.017), active forward elevation (137° ± 27.4° vs 129° ± 29.8; P = 0.031). Conclusion: At 2 or more years following RSA, the DP approach granted significantly better CS (by 6.5 points) and active forward elevation (by 8°) compared to the AS approach. The differences observed are clinically relevant and must be considered to manage patient expectations following RSA and for selecting surgical approach depending on their functional needs. Level of evidence: III, comparative study.

Intraoperative repair of functional subscapularis during RSA by deltopectoral approach could improve internal rotation but does not prevent anterior dislocation.

INTRODUCTION: The role of the subscapularis following reverse shoulder arthroplasty (RSA) remains controversial as repair could restore adequate internal rotation and shoulder stability, but might compromise external rotation. The purpose of this multi-centre study, on a large cohort of RSAs performed using the deltopectoral approach, was to determine the effect of subscapularis preoperative status and intraoperative repair on range of motion, clinical scores and rates of complications at a minimum follow-up of 2 years. HYPOTHESIS: Repair of a functional subscapularis grants better internal rotation and stability without compromising external rotation. MATERIALS AND METHODS: We retrospectively reviewed records of all RSAs (n=916) performed by 14 surgeons that participated in a large national society symposium, and excluded 234 operated by the anterosuperior approach, 42 operated for rheumatoid arthritis, fractures, instability or post traumatic sequalae, and eight that had adjuvant latissimus dorsi tendon transfer (LDTT). This left 632 RSAs, in which the subscapularis was detached in 594, and repaired after detachment in 495. Patients completed pre- and postoperative Constant Score and postoperative Subjective Shoulder Value (SSV). Active forward elevation, active external rotation (ER), and active internal rotation (IR) were recorded pre- and postoperatively. Complications following RSA that required conservative treatment, reoperation without implant removal, as well as reoperation with implant removal were recorded. RESULTS: Of the initial cohort of 632 shoulders, 120 (19%) were lost to follow-up, 12 (2%) died due to causes unrelated to RSA, and 26 (4%) were revised with implant removal. Of the remaining 474 shoulders, 259 (55%) had a functional repaired subscapularis (Group FR), 59 (12%) had a non-functional repaired subscapularis (Group nFR), whereas 68 (14%) had a not repaired subscapularis (Group nR). Comparison of patient demographics revealed no significant differences among the three groups. Postoperative Constant Score (p=0.031) and SSV (p=0.016) were significantly different among the three groups, but effect sizes were small and not clinically relevant. Differences in postoperative ER as well as postoperative IR were not significant among the three groups: 91 (35%) gained functional IR in Group FR, 11 (19%) in Group nFR, and 13 (19%) in Group nR. Three shoulders (1.2%) reported subjective instability and 1 (0.4%) dislocated in Group FR, but none in either Groups nFR or nR. DISCUSSION: Despite statistically significant differences in Constant Score and SSV among the three groups, the clinical relevance of these differences is negligible, so repair of functional subscapularis has little or no influence on functional outcomes. During RSA by deltopectoral approach, repair of a functional subscapularis could slightly improve internal rotation in some patients but does not compromise external rotation, forward elevation or clinical scores, while repair of a non-functional subscapularis, compared to non-repair, did not improve range of motion or clinical scores. LEVEL OF EVIDENCE: III; retrospective comparative.

Management of acute grade IV and greater acromioclavicular dislocations: Open acromioclavicular brace versus arthroscopic double DogBone® endobutton.

INTRODUCTION: Several surgical techniques exist to manage grade IV acute acromioclavicular dislocation (ACD). However, the conventional acromioclavicular brace technique (ACB) has never been compared to the arthroscopic DogBone® (DB) double endobutton technique. The aim of this work was to compare the functional and radiological results of DB stabilization with those of ACB. HYPOTHESIS: DB stabilization provides similar functional results with a low rate of radiological recurrences compared to ACB. MATERIAL AND METHODS: This is a case-control study comparing 17 cases of ACD operated by DB (DB group) between January 2016 and January 2021 with 31 cases of ACD operated by ACB (ACB group) between January 2008 and January 2016. The primary outcome was the difference in the D/A ratio (reflecting vertical displacement) measured on an anteroposterior acromioclavicular (AC) X-ray compared between the 2 groups at one-year after surgery. The secondary outcome was a clinical evaluation at one-year using the Constant score and clinical AC instability. RESULTS: At revision, the mean D/A ratio in the DB and ACB groups was 0.4±0.5 [-0.4-1.6] and 1.6±0.3 [0.8-3.1] respectively (p>0.05). Two patients (11.7%) in the DB group had implant migration with radiological recurrence while 14 patients (33%) had radiological recurrence in the ACB group (p<0.05). CONCLUSION: The DB technique limits the radiographic recurrence of acute ACD with an equivalent functional result at 1-year postoperatively compared to the conventional ACB technique, which implicitly requires a second operation for hardware removal. The DB technique has become the technique of choice in first-line treatment of acute grade IV ACD. LEVEL OF EVIDENCE: III; retrospective case-control series.

Clinical and radiological outcomes of internal fixation of complex talar neck and body fractures with locking plates through a dual approach.

INTRODUCTION: Talar fractures are rare and surgical treatment has not been standardized. The literature is rather poor on preserving talar vascularization in single or dual approaches. A dual approach allows better exposure and should limit devascularization. Locking plates are one of the modern solutions for challenging comminuted fractures. The aim of this study was to determine clinical and radiological outcomes in complex talar fracture (CTF) of the neck and body, fixed by locking plates through a dual approach with at least one locking plate. HYPOTHESIS: Locking-plate fixation of CTF through a dual approach leads to good clinical outcome. MATERIAL AND METHODS: A single-center retrospective study included 12 cases of CTF treated between January 2007 and May 2019. 3D CT was systematically performed to plan surgery. A dual approach and at least one locking plate were used for fixation. Clinical outcome was evaluated on AOFAS score. Reduction quality and correlation to clinical results were evaluated, reduction with<2mm joint step being considered satisfactory. Consolidation rate and occurrence of avascular necrosis of the talus (ANT), post-traumatic arthritis (PTA) and postoperative complications were analyzed. RESULTS: Mean follow-up was 27 months (range, 15-47). Mean AOFAS score was 70±18 (range, 30-97). Inframillimetric reduction was achieved in 67% of cases, without significant correlation with clinical results. The consolidation rate was 91.6%, ANT rate 18.2% and PTA rate 45.5%. One patient presented septic osteoarthritis secondary to scar necrosis. CONCLUSION: Locking plate fixation of CTF through a dual approach provided acceptable clinical outcomes. LEVEL OF EVIDENCE: IV; retrospective study.

Does isolated arthroscopic anterior acromioplasty modify critical shoulder angle?

INTRODUCTION: Critical shoulder angle (CSA)>35° correlates significantly with primary rotator cuff tear and re-tear after repair. Acromial axial orientation varies between individuals. The present study aimed to assess the impact of strictly anterior acromioplasty on CSA. HYPOTHESIS: CSA is reduced by arthroscopic anterior acromioplasty. MATERIAL AND METHODS: A single-center retrospective study included patients receiving isolated arthroscopic acromioplasty between January 2016 and December 2017. Exclusion criteria comprised history of surgery and fracture or dislocation of the shoulder. Pre- and post-operative AP shoulder radiographs were taken. The angle subtended by a line between the inferior and superior edges of the glenoid and a line between the inferior edge of the glenoid and the most lateral point on the acromion was measured. RESULTS: One hundred and two patients were included: mean age, 50.5±10.1 years (range, 23-82 years). Mean CSA was 34.7±4.4° (range, 26-48°) preoperatively and 31.7±3.7° (range, 23-40°) postoperatively (p<0.001). In the group with CSA >35°, the decrease was significant: 34.4±3.2° (range, 28-40°) versus 38.9±2.8° (range, 36-48°) (p<0.001), with 64% CSA <35° after isolated anterior acromioplasty. DISCUSSION: CSA was decreased by arthroscopic acromioplasty. However, in 36% of cases with preoperative CSA >35°, CSA was not normalized. CONCLUSION: Anterior arthroscopic acromioplasty significantly reduced CSA in the overall population, and especially in case of high CSA. LEVEL OF EVIDENCE: IV; retrospective study.

Does anterior arthroscopic acromioplasty modify critical shoulder angle?

INTRODUCTION: Critical shoulder angle (CSA) is measured on AP view in neutral rotation as the angle subtended by the tangent to the glenoid and the lateral edge of the acromion. CSA >35° is a risk factor for primary rotator cuff tear and iterative tear after cuff repair. The aim of the present study was to assess change in CSA following arthroscopic anterior acromioplasty. HYPOTHESIS: CSA is decreased by arthroscopic anterior acromioplasty. MATERIAL AND METHOD: A single-center retrospective descriptive observational study included patients undergoing arthroscopic acromioplasty between January 2016 and December 2017, for whom strictly AP pre- and post-operative radiographs were available. Patients with history of surgery, fracture or dislocation in the same shoulder were excluded. RESULTS: 102 patients were included; mean age, 50.5 years (range, 23-82 years). Mean preoperative CSA was 34.7±4.4° (range, 26-48°) and postoperative CSA 31.7±3.7° (range, 23-40°) (p<0.001). In the pathological CSA group (>35°), the values were 38.9±2.8° (36-48°) and 34.4±3.2° (28-40°) (p<0.001), with a 64.3% rate of correction after acromioplasty. DISCUSSION: CSA decreased after arthroscopic acromioplasty. Even so, 36.7% of pathological CSAs (>35°) were not corrected, with risk of rotator cuff tear. CONCLUSION: Anterior arthroscopic acromioplasty significantly reduced CSA overall, notably in case of high CSA. LEVEL OF EVIDENCE: IV, retrospective study.

Does the retention of osseointegrated prosthetic implants during the surgical management of chronic infections following reverse total shoulder arthroplasty (RTSA) influence functional outcomes without impacting the efficacy of the infection treatment?

INTRODUCTION: The gold standard (GS) for treating chronic infections following reverse total shoulder arthroplasty (RTSA) is a complete exchange of the prosthesis carried out in one or two stages. This surgical procedure, which may damage the bone stock, can result in poor functional outcomes due to intraoperative complications. The purpose of this study was to compare the GS to a surgical technique that retained osseointegrated implants: the partial one-stage exchange. HYPOTHESIS: Partial one-stage exchange was effective in treating chronic infections after RTSA (no recurrent infection) and resulted in better functional outcomes than the GS. MATERIALS AND METHODS: This retrospective single-center study included 18 patients with chronic infection after a primary RTSA. Two treatments were compared in a non-randomized fashion. The first included 11 patients who underwent a partial one-stage exchange with implant retention in case of macroscopic osseointegration. The second included seven patients who were treated with the GS: six patients with a complete one-stage exchange and one patient with a two-stage surgical approach. The absence of recurrent infection and functional outcomes were assessed after a minimum of two years. RESULTS: There were no statistically significant differences in treatment efficacy between the two strategies: 91% vs. 100%, respectively. The partial one-stage exchange resulted in a significantly improved shoulder function compared to the GS with postoperative Constant scores of 55±14.58 vs. 44±14.45, respectively (p=.03). In the partial one-stage exchange group, there was a significantly improved shoulder function with a preoperative Constant score of 40 [28-55]±9.04 preoperatively vs. 55 [25-75]±14.58 postoperatively (p=.01). The GS treatment did not significantly improve the postoperative function (p=.09). DISCUSSION: Partial one-stage exchange does not compromise treatment efficacy of chronic infections after RTSA. This technique resulted in better shoulder function than a conventional GS-type management. A study with greater statistical power is required. LEVEL OF EVIDENCE: III; clinical series, retrospective, single-center.

Osteoarthritis of the shoulder in under-50 year-olds: A multicenter retrospective study of 273 shoulders by the French Society for Shoulder and Elbow (SOFEC).

INTRODUCTION: Osteoarthritis (OA) of the shoulder in under-50 year-olds is rare, and treatment is delicate. Shoulder replacement incurs frequent long-term risk of progression and a high revision rate, making it unsuited to young active patients. The aim of the present study was to determine the epidemiology of shoulder OA in under-50 year-olds and to assess the clinical results of the various treatment options. HYPOTHESIS: The main study hypothesis was that well-conducted non-operative treatment can allow shoulder replacement to be postponed. The secondary hypothesis was that anatomic total shoulder arthroplasty (TSA) is the treatment of choice when other options fail. MATERIALS AND METHODS: A multicenter retrospective study included primary (POA) and post-instability osteoarthritis (PIOA) in patients aged≤50years at symptom onset. Exclusion criteria comprised post-traumatic OA, rheumatoid arthritis and necrosis. Two hundred and sixty-six patients for 273 shoulders were included from 13 shoulder surgery centers: 2 types of non-operative treatment (28 by platelet-rich plasma [PRP] and 88 by viscosupplementation), 73 arthroscopies, and 150 implantations (62 humeral hemiarthroplasties [HA], comprising 10 hemi-metal, 24 hemi-pyrocarbon and 28 hemi-resurfacing; 77 anatomic total prostheses, and 11 reverse prostheses). Minimum follow-up was 12 months for non-operative treatment and 24 months for arthroplasty (some patients having both). Endpoints comprised Constant score, Subjective Shoulder Value (SSV) and number of complications/revision procedures. RESULTS: Mean age at treatment was 43 years (range, 23-65 years), with 75% male predominance. Symptom onset was earlier in PIOA than in POA: 36 vs. 39 years (range, 20-50 years). PRP and viscosupplementation postponed implantation by a mean 3.5 years in 86% of cases, as did arthroscopy in 56%. ER1 restriction was the most negative factor. At 74 months' follow-up for HA and 95 months for TSA, mean Constant score was significantly lower for HA (56 vs. 67; p=0.004), with higher rates of complications (31% vs. 11%) and implant exchange (13% vs. 9%). DISCUSSION/CONCLUSION: PRP, viscosupplementation and arthroscopy allow implantation to be postponed until the shoulder becomes stiff and painful. In case of failure, TSA is the most effective solution in the medium-term. LEVEL OF EVIDENCE: IV a; therapeutic study - investigating the results of treatment.

Histochemical identification of wear debris released by alumina-on-alumina hip prostheses in the periprosthetic tissues.

BACKGROUND: Tribological studies have shown that the most used couples for hip prostheses consist of metal-on-polyethylene and alumina-on-alumina prostheses. Over time, wear products accumulate in the joint cavity and in the periprosthetic tissues. Although polyethylene and metal are easily identifiable by microscopy in periprosthetic tissues, alumina particles are very difficult to identify. HYPOTHESIS: The fluorescent azo-dye lumogallion was evaluated as a suitable histochemical stain for alumina particles in periprosthetic tissues. MATERIAL AND METHOD: In 28 patients who had a prosthetic revision of an alumina-on-alumina prosthesis, periprosthetic tissues were removed and embedded in paraffin; sections were stained with HPS (for conventional diagnosis) or with lumogallion. Sections were examined for wear particles in light and fluorescence microscopy. Some sections were counter-stained using DAPI for visualization of cell nuclei. RESULTS: The wear particles of the alumina-alumina prostheses were very difficult to identify on the HPS stained sections; they were clearly evidenced by lumogallion staining with a bright orange fluorescence. The stain revealed large quantities of particles (of the order of several thousand per section). Only two patients had no particles. The staining technique identified numerous particles that were not visible on HPS-stained sections in macrophages, synoviocytes and fibroblasts. CONCLUSION: This staining, which has been validated in neuromuscular pathology for the identification of alumina used as a vaccine adjuvant, gave successful results in the present study. Alumina particles are modified when they are phagocytized by macrophages. lumogallion staining easily shows the presence of thousands of wear particles released by alumina-on-alumina prostheses in periprosthetic tissues. LEVEL OF EVIDENCE: V expert opinion study.

Comparison of double screw fixation versus tension-band fixation after olecranon osteotomy for complex distal humerus fractures.

INTRODUCTION: Supra- and intercondylar elbow fractures are surgically challenging given the intra-articular comminution. Various surgical approaches have been described. Among these-olecranon osteotomy-provides optimal joint exposure but is associated with several complications. Tension band wiring (TBW) is the most commonly used fixation method. We hypothesized that double screw fixation would lead to fewer surgical revisions than TBW (all causes included) after olecranon osteotomy. METHODS: We carried out a single-center retrospective study of 39 patients, treated between January 2007 and April 2016, for a supra- or intercondylar elbow fracture using the transolecranon exposure. There were 34 type C fractures (13 C1, 6 C2 and 15 C3), 3 type B fractures and 2 type A fractures, based on the AO classification. Fourteen patients received double screw fixation and 25 received TBW. The primary outcome measure was the number of surgical revisions, regardless of cause. Secondary outcome measures were the number of surgical revisions for olecranon nonunion, fixation failure or fixation device removal due to pain. RESULTS: There were significantly more surgical revisions in the TBW group than in the double screw fixation group: 3 (21%) versus 14 (56%) (p=0.049, Fisher test). The three main reasons for revision in the TBW and double screw fixation groups were removal of the fixation device due to soft tissue impingement (11 [44%] versus 2 [14%]; p=0.08), failure of the olecranon fixation (6 [24%] versus 1 [7%] p=0.38), and olecranon nonunion (4 [16%] versus 0 [0%] p=0.27). DISCUSSION: There are no published studies on the outcomes of this surgical technique. The posterior transolecranon approach provides the best exposure at the elbow joint. TBW fixation is associated with multiple complications. Double screw fixation for olecranon fractures yields good clinical and radiological outcomes. CONCLUSION: Based on our findings, double screw fixation of the olecranon results in fewer surgical revisions (all causes combined) than TBW in supra- and intercondylar elbow fractures operated by a transolecranon approach. LEVEL OF EVIDENCE: IV.

WITHDRAWN: Does anterior arthroscopic acromioplasty modify critical shoulder angle?

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Fast-track care for pertrochanteric hip fracture: What impact on function and autonomy after discharge?

INTRODUCTION: Fast-track treatment of pertrochanteric fracture is being developed in traumatology. The present study hypothesis was that fast-track treatment of pertrochanteric fracture does not jeopardize patient autonomy. MATERIAL AND METHOD: A single-center prospective comparative observational study, conducted from 2014 to 2016 in the University Hospital of Angers, France, included patients presenting with isolated A1 or A2 pertrochanteric fracture on the AO classification, managed by intramedullary nailing and requiring transfer to Post-acute Recovery (PAR). The fast-track exposure group were transferred directly on postoperative day 1, while the non-exposure group received postoperative care in the surgery department before transfer to PAR. The main endpoint was difference in Parker score between admission and discharge. Secondary endpoints comprised type of walking aid at discharge and destination of discharge from PAR. RESULTS: 109 patients were initially included, with 54 patients (27 pairs) after matching. There was a significant difference in reduction in Parker score in favor of fast-track: -1.27 (95% CI: -2.27; -0.32) (p=0.012). There were no differences in amount or type of aid at discharge or discharge destination, although there was a trend toward greater discharge to the initial place of residence with fast-track. DISCUSSION: Orthopedics is heading to the fast-track. Previous studies reported shorter hospital stay, comparable survival and complications rates, and significant cost-saving. The present study addressed progression: fast-track patients showed significantly less loss of walking autonomy. CONCLUSION: Fast-track management of pertrochanteric fracture significantly reduced loss of walking autonomy, without significant impact on discharge destination or walking aids. LEVEL OF EVIDENCE: IIB, exposure/non-exposure cohort.

Imaging of shoulder arthroplasties and their complications: a pictorial review.

Currently, an increasing number of patients benefit from shoulder prosthesis implantation. Radiologists are therefore more often confronted with imaging examinations involving shoulder arthroplasty, whether during a dedicated examination or incidentally. Standard radiography is the first-line imaging modality in the follow-up of these implants, before the possible use of cross-sectional imaging modalities (computed tomography and magnetic resonance imaging), ultrasound, or nuclear medicine examinations. Shoulder arthroplasties are divided into three categories: reverse shoulder arthroplasty, total shoulder arthroplasty, and partial shoulder joint replacement (including humeral hemiarthroplasty and humeral head resurfacing arthroplasty). Each of these prostheses can present complications, either shared by all types of arthroplasty or specific to each. Infection, periprosthetic fractures, humeral component loosening, heterotopic ossification, implant failure, and nerve injury can affect all types of prostheses. Instability, scapular notching, and acromial fractures can be identified after reverse shoulder arthroplasty implantation. Glenoid component loosening and rotator cuff tear are specific complications of total shoulder arthroplasty. Progressive wear of the native glenoid is the only specific complication observed in partial shoulder joint replacement. Knowledge of different types of shoulder prostheses and their complications' radiological signs is crucial for the radiologist to initiate prompt and adequate management.

Osteocyte staining with rhodamine in osteonecrosis and osteoarthritis of the femoral head.

Death of osteocytes is synonymous of bone death. Aseptic osteonecrosis of the femoral head is a lesion characterized by the death of osteocytes occurring after major vascular changes. The evolution may lead to hip osteoarthritis, which requires total hip arthroplasty in most cases. Evolution of aseptic osteonecrosis in four radiological stages is well known. We analyzed 24 femoral heads from patients with osteonecrosis or osteoarthritis, retrieved at the time of surgery for a hip arthroplasty. The aim of the study was to clearly identify the necrotic bone from the living bone in the histological samples. The femoral heads were sawed, and a large sample was harvested in the superior zone; it was stained en-bloc with rhodamine dissolved in formalin to make the osteocytes fluorescent under UV light microscopy. Undecalcified sections, 7 µm thick, were obtained on a heavy-duty microtome. A micrographic analysis using two UV excitation wavelengths visualized the living osteocytes (in green) and the bone matrix (in blue). A simple method to prepare combined images is described. In addition, the blocks can be analyzed by confocal microscopy to visualize more details. It is possible to identify at low magnification the osteocytes within the bone matrix and the osteonecrotic areas where osteocytes have disappeared. Identification of osteocytes showed that newly formed bone packets are laid on dead trabeculae in patients with aseptic osteonecrosis or with osteoarthritis. In the osteosclerotic areas, the enlarged trabeculae have a dead central core surrounded by recently apposed bone structure units.

Texture analysis of trabecular bone around RM-Pressfit cementless acetabulum in a series of 46 patients during a 5 year period.

BACKGROUND: Cementless total hip arthroplasty (THA) is a common procedure producing excellent clinical results. Their long-term survival is nevertheless burdened by loosening of the acetabular part caused by changes in the distribution of strains around the cup. In this context the RM-Pressfit® cup has been developed, resulting in a more harmonious distribution of the strains. HYPOTHESIS: Texture analysis of X-ray films can evaluate the evolution of trabecular bone micro-architecture during the five years following THA with a RM-Pressfit® cup. MATERIAL AND METHOD: A monocentric series of 46 hips was reviewed regularly within five years post- surgery. Radiographic evaluation of the operated hip was done on frontal digitized radiographs of the pelvis to follow evolution of bone micro-architecture in the #2 zone of De Lee and Charnley. Texture analysis using fractal algorithms was done at D0, 6 months, 1, 2 and 5 years post-THA. The fractal methods used included the skyscrapers and the dynamic blanket methods with 3 different structuring elements (a cross, a horizontal and a vertical vector). RESULTS: The RM-Pressfit® caused significant changes in the distribution of strains around the acetabulum that preserved the bone volume over a 5-year period post-surgery. This corresponds to an improvement of the trabecular micro-architecture around the acetabular cups. CONCLUSION: A statistically significant increase in the four fractal dimensions considered corresponded to an improved trabecular bone micro-architecture revealed by texture analysis, a non-invasive method that can be used on digitized X-ray images. LEVEL OF EVIDENCE: IIIb, Case control study, retrospective design.

Intramedullary nailing for adult open tibial shaft fracture. An 85-case series.

INTRODUCTION: Treatment of open tibial shaft fracture is controversial due to the risk of infection. We assessed results in a continuous series of open tibial shaft fractures treated by primary intramedullary nailing. HYPOTHESIS: Factors can be determined for non-union and onset of infection following primary intramedullary nailing in open tibial shaft fracture. PATIENTS AND METHOD: A retrospective study assessed open tibial shaft fractures treated by primary intramedullary nailing between January 2007 and December 2013. Fractures were classified on the AO and Gustilo classifications. Infection rates and time to union were compared. RESULTS: Eighty-five patients (85 fractures) were included: 13 Gustilo type I, 43 type II, 19 type III-A and 10 type III-B. Eight patients had infection (9%). Healing and union were obtained after nail exchange and reaming in 5 cases, and after bone transport in 2. One patient showed non-union at last follow-up. Infection risk did not correlate with Gustilo (p=0.55) or AO type (p=0.69). The interval between trauma and wound debridement was significantly longer in infected patients (p=0.048). Eighty-three fractures (97.6%) healed, at a mean 6.9±6.1 months (range, 2-40). Non-union was associated with AO type (p=0.04), and showed a non-significant association with Gustilo type (p=0.06). DISCUSSION: Time to treatment was the only factor influencing risk of infection. Non-union was related to AO comminution grade. Primary intramedullary nailing seemed reliable if treatment was early, with rigorous debridement. The advantages then are early resumption of weight-bearing and low patient burden. LEVEL OF EVIDENCE: V, retrospective study.

Fast track care for pertrochanteric hip fractures: How does it impact length of stay and complications?

INTRODUCTION: The medical and economic impact of treating pertrochanteric hip fractures is growing. We hypothesized that fast track surgery of pertrochanteric fractures would reduce the length of stay (LOS) without compromising the quality of care. MATERIALS AND METHODS: This was a prospective, observational, single-center cohort study conducted between 2014 and 2016 at the Angers Teaching Hospital in France. The enrolled patients had an isolated A1 or A2 proximal femur fracture (AO classification) that was treated surgically by intramedullary nailing and required post-acute rehabilitation (PAR) care. The exposed FT cohort was transferred into the PAR pathway on postoperative day 1. The non-exposed (control) group was provided with postoperative care in the surgery unit before transfer to PAR. The primary outcome was the total LOS (LOS in surgery+LOS in PAR). The secondary objectives were to determine the immediate survival, 1-year survival, postoperative complications and average cost of hospitalization. RESULTS: The study enrolled 109 patients initially, with 54 patients eligible for analysis after matching (27 pairs). The LOS in PAR and total LOS were 45.85±19.24 days and 48.56±19.36 days in the FT group (n=27), and 68.41±48.77 days and 77.85±48.80 days in the control group (n=27). Thus the LOS in PAR and total LOS were significantly lower in the FT group (p=0.022, p=0.003). There was no significant difference in the number of early deaths, complications, and 1-year survival without rehospitalization between cohorts. The mean cost per patient was lower in the FT cohort. DISCUSSION: The FT pathway has already been adopted in orthopedics. For patient who suffer a hip fracture, it contributes to reducing the total LOS without negatively impacting the quality of care. Early health economics studies support this care pathway. CONCLUSION: The FT approach to treating pertrochanteric fractures reduces total LOS without increasing mortality or complication rates. The 1-year survival is comparable. LEVEL OF EVIDENCE: IIB, Exposed/Unexposed cohort.

Biomaterial granules used for filling bone defects constitute 3D scaffolds: porosity, microarchitecture and molecular composition analyzed by microCT and Raman microspectroscopy.

Biomaterials are used in the granular form to fill small bone defects. Granules can be prepared with a grinder from trabecular bone samples or provided as synthetic biomaterials by industry. Granules occupy the 3D-space and create a macroporosity allowing invasion of vascular and bone cells when the inter-granular pores are larger than 300 µm. We compared the 3D-porosity of granule stacks obtained or prepared with nine biomaterials Osteopure® , Lubboc® , Bio-Oss® , CopiOs® , TCP Dental® , TCP Dental HP® , KeraOs® , and TCH® in comparison with that of human trabecular bone. For each biomaterial, two sizes of granules were analyzed: 250-1000 and 1000-2000 µm. Microcomputed tomography determined porosity and microarchitectural characteristics of granular stacks and Raman microspectroscopy was used to analyze their composition. Stacks of 250-1000 µm granules had a much lower porosity than 1000-2000 µm granules and the maximum frequency of pores was always centered at 200-250 µm. One biomaterial contained substantial amount of cortical bone (Bio-Oss® ). The highest porosity and pore size was obtained with TCP Dental HP. Raman spectroscopy found differences in biomaterials of the same composition. Stacks of granules represent 3D scaffolds resembling trabecular bone with an interconnected porous microarchitecture. Small granules have created pores <300 µm in diameter; this can interfere with vascular colonization. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 415-423, 2019.