Injectable macroporous naturally-derived apatite bone cement as a potential trabecular bone substitute.

In this study, we have formulated a novel apatite bone cements derived from natural sources (i.e. eggshell and fishbone) with improved qualities that is, porosity, resorbability, biological activity, and so forth. The naturally-derived apatite bone cement (i.e. FBDEAp) was prepared by mixing hydroxyapatite (synthesized from fishbone) and tricalcium phosphate (synthesized from eggshell) as a solid phase with a liquid phase (a dilute acidic blend of cement binding accelerator and biopolymers like gelatin and chitosan) with polysorbate (as liquid porogen) to get a desired bone cement paste. The prepared cement paste sets within the clinically acceptable setting time (≤20 min), easily injectable (>85%) through hands and exhibits physiological pH stability (7.3-7.4). The pure apatite phased bone cement was confirmed by x-ray diffraction and Fourier transform infrared spectroscopy analyses. The FBDEAp bone cement possesses acceptable compressive strength (i.e. 5-7 MPa) within trabecular bone range and is resorbable up to 28% in simulated body fluid solution within 12 weeks of incubation at physiological conditions. The FBDEAp is macroporous in nature (average pore size ~50-400 µm) with interconnected pores verified by SEM and micro-CT analyses. The FBDEAp showed significantly increased MG63 cell viability (>125% after 72 h), cell adhesion, proliferation, and key osteogenic genes expression levels (up to 5-13 folds) compared to the synthetically derived, synthetic and eggshell derived as well as synthetic and fishbone derived bone cements. Thus, we strongly believe that our prepared FBDEAp bone cement can be used as potential trabecular bone substitute in orthopedics.

Fabrication of injectable antibiotic-loaded apatitic bone cements with prolonged drug delivery for treating post-surgery infections.

Antibiotic-loaded bioactive bone substitutes are widely used for treating various orthopedic diseases and prophylactically to avoid post implantation infection. Calcium deficient hydroxyapatite (also known as apatitic bone cement) is a potential bioactive bone substitute in orthopedics due to its chemical composition similar to that of natural bone minerals. In this study, fabrication of mannitol (a solid porogen) incorporated injectable synthetic (Syn) and eggshell derived (ESD) apatitic bone cements loaded with antibiotics (gentamicin/meropenem/ rifampicin/vancomycin) was investigated. The release kinetics of the antibiotics were studied by fitting them with different kinetic models. All the antibiotics-loaded apatitic bone cements set within clinically accepted setting time (20 ± 2 min) and with good injectability (>70%). The antibiotics released from these bone cements were found to be controlled and sustained throughout the study time. Weibull and Gompertz (applies in least initial burst and sustain drug release rate models) were the best models to predict the release behavior. They cements had acceptable compressive strength (6-10 MPa; in the range of trabecular bone) and were biodegradable (21%-27% within 12 weeks of incubation) in vitro in simulated body fluids at physiological conditions. These bone cements showed excellent antibacterial activity from day 1 onwards and no bacterial colony was found from day 3 onwards. The viability of MG63 cells in vitro after 72 h was significantly higher after 24 h (i.e., ~110%). The cells were well attached and spread over the surface of the cements with extended morphology. The ESD antibiotic-loaded apatitic bone cements showed better injectability, degradation and cytocompatibility compared when compared to Syn antibiotic-loaded apatitic bone cements. Thus, we believe that the ESD antibiotic-loaded apatitic bone cements are suitable as potential injectable bone substitutes to avoid post-operative implant associated and other acute or chronic bone infections.

Fabrication of macroporous apatite bone cements for non-load bearing orthopedic applications.

Calcium deficient hydroxyapatite (CDHA)-based apatite forming bone cements are well known for their bioactivity and bioresorbability. The formulation of CDHA-based cements with improved macroporosity, injectability, and resorbability has been investigated. The solid phase consists of nanocrystalline hydroxyapatite (HA) and tricalcium phosphate (ß-TCP). The liquid phase is diluted acetic acid with disodium hydrogen phosphate as binding accelerator along with gelatin and chitosan to improve the injectability. A porogen agent either mannitol (as solid porogen) or polysorbate (as liquid porogen) is also used to improve the porosity. All combined in fine-tuned composition results in optimal bone cements. The cement sets within the clinically preferred setting time (≤20 min) and injectability (>70%) and also stable at physiological pH (i.e., ~7.3-7.4). The XRD and FT-IR analysis confirmed the formation of CDHA phase on day 7 when the after-set cement immersed under phosphate buffer solution (PBS) at physiological conditions. The cements were found to have acceptable compressive strength for trabecular bone substitute. The cements were macroporous in nature with average pore size between 50 and 150 µm and were interconnected as confirmed by SEM, micro-CT and MIP analysis. The prepared cements are degradable up to 22% and 19% in simulated body fluid and PBS respectively within 10 weeks of immersion at physiological conditions. The cements exhibit higher viability (%) (>110%) with L929 and MG63 cells compared to the control after 3 days of incubation. They also show increased proliferation, well spreading and extended filopodia with MG63 cells. Overall, the developed apatite forming bone cements seems to be suitable for low or non-load bearing orthopedic applications.

Efficacy and cost-effectiveness of universal pre-operative iron studies in total hip and knee arthroplasty.

BACKGROUND: The prevalence of anaemia in patients planned for total hip and knee arthroplasty is about 20%. Optimising pre-operative haemoglobin levels by iron supplementation has been shown to decrease transfusion rates, complications and associated morbidity. The need for universal screening with iron studies of all elective arthroplasty patients is not clearly defined at present. METHODS: Retrospective review of 2 sequential cohorts of patients undergoing primary hip or knee arthroplasty by a single surgeon at a single centre between January 2013 and December 2017. The first group of patients underwent pre-operative iron studies only if found to be anaemic, with a haemoglobin below 12g/dl. From January 2015, all patients irrespective of the presence of anaemia were screened with a complete iron profile before surgery. Patients with a confirmed iron deficiency were administered with intravenous iron prior to surgery. The 2 cohorts were compared with regard to blood transfusion rate post-operatively and cost efficiency for universal screening with iron studies. RESULTS: There was a net decrease in the allogenic blood transfusion rate from 4.76 to 2.92% when universal iron studies were introduced but the difference was not statistically significant. Obtaining universal pre-operative iron studies is cost neutral with the price of allogenic blood transfusion in a similar cohort. We also diagnosed 5 patients with occult malignancies. CONCLUSIONS: Universal screening with pre-operative iron studies and iron infusion in elective arthroplasty patients may reduce allogenic blood requirements and is cost neutral. An additional benefit is the potential to diagnose asymptomatic malignancies. Further studies are required to show the true benefit of universal pre-operative iron screening.

Use of an Angled Blade Plate for 31A3 Intertrochanteric Fractures.

BACKGROUND: A subgroup of pertrochanteric fractures-namely, the AO/OTA 31A3 fracture-continues to be a difficult problem to treat, even with cephalomedullary nails. We present the results for 26 patients with a 31A3 fracture treated with the angled blade plate. METHODS: The records of 26 consecutive patients with a 31A3 fracture that was treated operatively with the angled blade plate device between 2007 and 2012 at our center were reviewed, and the patients were contacted for follow-up. The functional outcome (traumatic hip rating score) and radiographic outcome (the neck-shaft angle at the time of fixation and final follow-up) were obtained for 20 of the 26 patients at a minimum follow-up of 1 year. RESULTS: All 26 patients had primary surgery. At final review, 2 patients had died and 4 had been lost to follow-up. Of the 4 patients lost to follow-up, 2 had revision of the fixation with the angled blade plate. Of the 20 patients with follow-up, 1 had malreduction and implant failure but eventually had healing after revision of the fixation with the angled blade plate. The mean traumatic hip rating score at the time of follow-up was 50.0 with 4, 14, and 2 patients having excellent, good, and failed outcomes, respectively. The mean neck-shaft angle at the time of final union was 126.16°, which was an average of 4° less than that on the unaffected side. However, this did not correlate with functional outcome. There was no significant difference between the immediate postoperative and final neck-shaft angles. CONCLUSIONS: This study demonstrated that blade plate fixation for 31A3 fractures is associated with low rates of failure (15%), revision surgery (15%), and infection (15%), which are comparable with the results of nail fixation (range, 5% to 12%) and superior to those of sliding hip screw fixation. This large series demonstrates that the angled blade plate can be utilized for these complex fractures and should be part of the armamentarium for these injuries. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Intravenous Mannitol reduces intracompartmental pressure following tibia fractures: A randomized controlled trial.

PURPOSE: Impending compartment syndrome is a common event following closed tibia fractures, which can progress to sinister compartment syndrome. Fasciotomy is the only definitive treatment available, though it has its own drawbacks and complications. Medical management at present consists of limb elevation and adequate hydration. This study aims at determining whether intravenous administration of Mannitol reduced the intracompartmental pressure in patients with closed tibial fractures. METHODS: This is a double blinded, randomized control trial done in a single tertiary care center in India. Forty-five patients were recruited between February 2012 and October 2012. Forty patients who presented to the emergency department with isolated, closed, high velocity, and proximal 2/3 tibia fractures were included in this study. Patients with contraindication to Mannitol were excluded. They were allocated into 2 groups by the investigator using computer generated randomization. The pressure in the anterior compartment of the leg was measured with a handheld Stryker pressure monitor. Then either 20% Mannitol or 0.9% normal saline as given intravenously in a blinded manner, based on the randomization. The intracompartmental pressure was measured at 0, 1 and 3 h after the infusion. The participant, investigator and statistician were masked to the group assessment. RESULTS: There was no difference in intracompartmental pressures at 1 or 3 h, between the groups. However, in patients with the baseline of compartmental pressures ≥30 mmHg, Mannitol showed a marked reduction in pressure of 8.5 mmHg at 1 h compared to almost no change in pressure in the saline group. There were no adverse events with the use of Mannitol. CONCLUSIONS: This preliminary study appears to show that Mannitol is useful in the management of the increased compartment pressure. The limitations of this study were that it only involved a small group of patients and the baseline pressures in both the groups were not comparable. More studies are required before the use of Mannitol as a standard of care in the management of compartment syndrome can be established.

Similar regeneration of articular cartilage defects with autologous & allogenic chondrocytes in a rabbit model.

Background & objectives: Articular cartilage defects in the knee have a very poor capacity for repair due to avascularity. Autologous chondrocyte transplantation (ACT) is an established treatment for articular cartilage defects. Animal studies have shown promising results with allogenic chondrocyte transplantation since articular cartilage is non-immunogenic. In addition to being economical, allogenic transplantation has less morbidity compared to ACT. This study was undertaken to compare ACT with allogenic chondrocyte transplantation in the treatment of experimentally created articular cartilage defects in rabbit knee joints. Methods: Cartilage was harvested from the left knee joints of six New Zealand white rabbits (R1-R6). The harvested chondrocytes were cultured to confluence and transplanted onto a 3.5 mm chondral defect in the right knees of 12 rabbits [autologous in 6 rabbits (R1-R6) and allogenic in 6 rabbits (R7-R12)]. After 12 wk, the rabbits were euthanized and histological evaluation of the right knee joints were done with hematoxylin and eosin and safranin O staining. Quality of the repair tissue was assessed by the modified Wakitani histological grading scale. Results: Both autologous and allogenic chondrocyte transplantation resulted in the regeneration of hyaline/mixed hyaline cartilage. The total histological scores between the two groups showed no significant difference. Interpretation & conclusions: Allogenic chondrocyte transplantation seems to be as effective as ACT in cartilage regeneration, with the added advantages of increased cell availability and reduced morbidity of a single surgery.

Characteristics of postoperative weight bearing and management protocols for tibial plateau fractures: Findings from a scoping review.

OBJECTIVE: To identify and describe the characteristics of existing practices for postoperative weight bearing and management of tibial plateau fractures (TPFs), identify gaps in the literature, and inform the design of future research. METHODS: Seven electronic databases and clinical trial registers were searched from inception until November 17th 2016. Studies were included if they reported on the surgical management of TPFs, had a mean follow-up time of ≥1year and provided data on postoperative management protocols. Data were extracted and synthesized according to study demographics, patient characteristics and postoperative management (weight bearing regimes, immobilisation devices, exercises and complications). RESULTS: 124 studies were included involving 5156 patients with TPFs. The mean age across studies was 45.1 years (range 20.8-72; 60% male), with a mean follow-up of 34.9 months (range 12-264). The most frequent fracture types were AO/OTA classification 41-B3 (29.5%) and C3 (25%). The most commonly reported non-weight bearing time after surgery was 4-6 weeks (39% of studies), with a further 4-6 weeks of partial weight bearing (51% of studies), resulting in 9-12 weeks before full weight bearing status was recommended (55% of studies). Loading recommendations for initial weight bearing were most commonly toe-touch/<10kg (28%), 10kg-20kg (33%) and progressive (39%). Time to full weight bearing was positively correlated with the proportion of fractures of AO/OTA type C (r=0.465, p=0.029) and Schatzker type IV-VI (r=0.614, p<0.001). Similar rates of rigid (47%) and hinged braces were reported (58%), most frequently for 3-6 weeks (43% of studies). Complication rates averaged 2% of patients (range 0-26%) for abnormal varus/valgus and 1% (range 0-22%) for non-union or delayed union. CONCLUSIONS: Postoperative rehabilitation for TPFs most commonly involves significant non-weight bearing time before full weight bearing is recommended at 9-12 weeks. Partial weight bearing protocols and brace use were varied. Type of rehabilitation may be an important factor influencing recovery, with future high quality prospective studies required to determine the impact of different protocols on clinical and radiological outcomes.

Outcome of Hip Impingement Surgery: Does Generalized Joint Hypermobility Matter?

BACKGROUND: Generalized joint hypermobility (JH) might negatively influence the results of surgical femoroacetabular impingement (FAI) treatment, as JH has been linked to musculoskeletal pain and injury incidence in athletes. JH may also be associated with worse outcomes of FAI surgery in thin females. PURPOSE: To (1) determine the results of FAI surgery at a minimum 2-year follow-up by means of patient-reported outcome measures (PROMs) and failure rates, (2) assess the prevalence of JH in FAI patients and its effect on outcomes, and (3) identify other risk factors associated with treatment failure. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: We included 232 consecutive patients (118 females; mean age, 36 years) with 244 hips surgically treated for symptomatic FAI between 2010 and 2012. All patients completed different PROMs preoperatively and at a mean follow-up of 3.7 years. Satisfaction questions were used to define subjective failure (answering any of the 2 subjective questions with dissatisfied/ very dissatisfied and/or didn't help/ made things worse). Conversion to total hip replacement (THR) was defined as objective failure. JH was assessed using the Beighton score. RESULTS: All PROM values significantly ( P < .001) improved from preoperative measurement to follow-up (Oxford Hip Score: 33.8 to 42.4; University of California at Los Angeles Activity Scale: 6.3 to 7.3; EuroQol-5 Dimension Index: 0.58 to 0.80). Overall, 34% of patients scored ≥4 on the Beighton score, and 18% scored ≥6, indicating generalized JH. Eleven hips (4.7%) objectively failed and were converted to THR. Twenty-four patients (10.3%) were considered as subjective failures. No predictive risk factors were identified for subjective failure. Tönnis grade significantly ( P < .001) predicted objective failure (odds ratio, 13; 95% CI, 4-45). There was a weak inverse association ( r = -0.16 to -0.30) between Beighton scores and preoperative PROM values. There were no significant associations between Beighton scores and postoperative PROM values or subjective failure rates, but patients who objectively failed had lower Beighton scores than did nonfailures (1.6 vs 2.6; P = .049). CONCLUSION: FAI surgery yielded favorable outcomes at short- to midterm follow-up. JH as assessed by the Beighton score was not consistently associated with subjective and objective results. Joint degeneration was the most important risk factor for conversion to THR. Although statistical significance was not reached, female patients with no joint degeneration, only mild FAI deformity, and higher Oxford scores at the time of surgery seemed to be at increased risk for subjective dissatisfaction.

Valgus osteotomy for nonunion and neglected neck of femur fractures.

Nonunion neck of femur can be a difficult problem to treat, particularly in the young, and is associated with high complication rates of avascular necrosis due to the precarious blood supply and poor biomechanics. The various treatment options that have been described can be broadly divided according to the aim of improving either biology or biomechanics. Surgeries aimed at improving the biology, such as vascularized fibula grafting, have good success rates but require high levels of expertise and substantial resources. A popular surgical treatment aimed at improving the biomechanics-valgus intertrochanteric osteotomy-optimizes conditions for fracture healing by converting shear forces across the fracture site into compressive forces. Numerous variations of this surgical procedure have been developed and successfully applied in clinical practice. As a result, the proximal femoral orientation for obtaining a good functional outcome has evolved over the years, and the present concept of altering the proximal femoral anatomy as little as possible has arisen. This technical objective supports attaining union as well as a good functional outcome, since excessive valgus can lead to increased joint reaction forces. This review summarizes the historical and current literature on valgus intertrochanteric osteotomy treatment of nonunion neck of femur, with a focus on factors predictive of good functional outcome and potential pitfalls to be avoided as well as controversies surrounding this procedure.

Retrograde Intramedullary Nailing for Recurrent Fracture in Congenital Pseudarthrosis of the Tibia.

We present the case of a 23-year-old male with congenital pseudarthrosis of the tibia, who had undergone treatment with Ilizarov ring fixation and had experienced 4 episodes of repeat fracture. He had associated type 1 neurofibromatosis, and his radiographs confirmed a type 6 Boyd's congenital pseudarthrosis of the left tibia, with concomitant arthritic ankle and subtalar joints. He was treated successfully with retrograde intramedullary nailing of the tibia and autologous bone grafting. At his final follow-up visit at 3 years postoperatively, he displayed complete union with no repeat fractures.

Draft Genome Sequences of Four Genetically Distinct Human Isolates of Streptococcus dysgalactiae subsp. equisimilis.

ß-Hemolytic group C and group G streptococci (GCS-GGS; Streptococcus dysgalactiae subsp. equisimilis) emerged as human pathogens in the late 1970s. We report here the draft genome sequences of four genetically distinct human strains of GCS-GGS isolated between the 1960s and 1980s. Comparative analysis of these genomes may provide a deeper understanding of GCS-GGS genome and virulence evolution.

Recurrent peripheral embolism following nonunion of the clavicle.

Vascular complications in closed clavicular fractures are uncommon, with an incidence of only 0.4%. Subclavian artery injury can present acutely or can have a delayed presentation with arm ischemia. We report the case of an undetected subclavian pseudoaneurysm in a patient with a nonunion fracture clavicle who was referred with persistent ischemia following attempted brachial embolectomy at another center, along with a review of literature to support the hypothesis that in addition to repair of the aneurysm, treatment of the psuedarthrosis by fixation of the clavicle is essential.

Indices affecting outcome of neglected femoral neck fractures after valgus intertrochanteric osteotomy.

OBJECTIVES: To evaluate preoperative neck resorption and postoperative valgus orientation as predictors of union and functional outcome after valgus intertrochanteric osteotomy for treatment of neglected femoral neck fractures and nonunions. DESIGN: Retrospective cohort study. SETTING: Tertiary care center. PATIENTS/PARTICIPANTS: Forty consecutive patients with neglected femoral neck fracture and nonunions were treated with valgus intertrochanteric osteotomy, and follow-up was available in 32 patients (average age, 43 years; range, 14-60 years; average nonunion duration, 6 ± 7 months; range, 1-36 months). INTERVENTION: Valgus intertrochanteric osteotomy. MAIN OUTCOME MEASUREMENTS: Clinical outcome was assessed with Harris hip score. Plain radiographs were evaluated for union, avascular necrosis, preoperative bone deficiency (neck resorption ratio), and postoperative femoral head fragment alignment (head-shaft angle). RESULTS: Follow-up at 5 ± 3 years (range, 2-12 years) after surgery showed union in 29 patients (91%), and Harris hip score was 82 ± 13 points (range, 63-100 points). The 3 patients with persistent nonunion at the neck of femur had neck resorption ratio <0.52. Increased postoperative head-shaft angle was associated with lower follow-up Harris hip score; postoperative valgus alignment >15 degrees compared with the contralateral side was associated with poor functional outcome. The presence of avascular necrosis did not affect the outcome. CONCLUSIONS: Valgus intertrochanteric osteotomy resulted in union and satisfactory functional outcome in most patients who had neglected femoral neck fractures and nonunions. Preoperative neck resorption ratio <0.5 was a risk factor for nonunion, and excessive valgus alignment was a risk factor for poor functional outcome after osteotomy. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

The efficacy of single-stage open intramedullary nailing of neglected femur fractures.

BACKGROUND: Neglected femur fractures are not rare in the developing world. Treatment options include single-stage open reduction and intramedullary nailing, or open release, skeletal traction, and then second-stage open intramedullary nailing, with bone grafting. Single-stage procedures have the potential advantage of avoiding neurovascular complications secondary to acute lengthening, but they require a second operation, with potentially increased resource use and infection risk. QUESTIONS/PURPOSES: We sought to determine the (1) likelihood of union, (2) complications and reoperations, and (3) functional results with single-stage open intramedullary nailing without bone grafting in patients with neglected femur fractures. METHODS: Between January 2003 and December 2007, 17 consecutive patients presented to our practice with neglected femoral shaft fractures. All were treated with single-stage nailing without bone grafting. There were 15 men and two women with a median age of 27 years. The average time from fracture to treatment was 13 weeks (range, 4-44 weeks). Eleven patients underwent open nailing with interlocked nails and six were treated with cloverleaf Kuntscher nails. Patients were followed for a minimum of 6 months (mean, 33 months; range, 6-72 months). The mean preoperative ROM of the knee was 28° (range, 10°-150°) and femoral length discrepancy was 3.1 cm (range, 1-5 cm). RESULTS: All fractures united and the mean time to union was 16 weeks (range, 7-32 weeks). There were no neurologic complications secondary to acute lengthening. The mean postoperative ROM of the knee was 130° (range, 60°-150°). All patients were able to return to preinjury work. Sixteen patients regained their original femoral length. CONCLUSIONS: One-stage open intramedullary nailing of neglected femoral diaphyseal fractures without bone grafting was safe and effective, and obviated the need for a two-stage approach. Although the findings need to be replicated in larger numbers of patients, we believe this technique may be useful in treating patients with this injury, and may offer advantages in resource-constrained environments.

Tuberculosis of and around the ankle.

Osteoarticular tuberculosis of the ankle joint is rare, and diagnostic delays are common with this condition. The aim of our report is to highlight the varied clinical and radiologic presentation of this entity. We present a retrospective review of 16 patients with tuberculosis in and around the ankle joint who were surgically treated during a 6-year period. The incidence of ankle joint involvement in extraspinal osteoarticular tuberculosis was 15.7% in our unit. The most common presentation in our series was chronic septic arthritis, followed by periarticular osseous lytic lesion. Tuberculous synovitis, tenosynovits, and retrocalcaneal bursitis were also seen. Osteopenia, the hallmark of osteoarticular tuberculosis, might not be seen in all forms of tuberculosis affecting this joint. Chemotherapy remains the mainstay of treatment. Adjuvant surgery is often required to establish the diagnosis and in the treatment of patients with deformity and widespread destruction of articular cartilage owing to delayed presentation.