Heterotopic Ossification in Total Ankle Arthroplasty: Case Series and Systematic Review.

Heterotopic ossification after total ankle arthroplasty (TAA) is a known sequela and has been reported to contribute to reduced range of motion and poor functional outcomes. However, conflicting results have been reported in the literature. The present study documents the incidence of heterotopic ossification for a novel fourth-generation fixed-bearing 2-component prosthesis and reports a systematic review of the literature. We reviewed the incidence and functional outcome of consecutively enrolled patients who underwent primary Infinity TAA between 2013 and 2015 in a prospective observational study. Preoperative and postoperative radiographic and functional outcome data were collected. A systematic review was also conducted investigating all published studies between 1998 and 2018 reporting the incidence of heterotopic ossification after TAA. The incidence of heterotopic ossification was 70.5% in the 61 patients who underwent primary TAA in the case series. There was no association between heterotopic ossification and American Orthopaedic Foot and Ankle Society (AOFAS) score, foot function index (FFI), visual analogue scale (VAS), and ankle osteoarthritis scale (AOS). Sixteen studies on 1339 TAA implants were included. The overall incidence of heterotopic ossification after TAA was 66.0% at average 3.6 years (range 22.2% to 100%). Four studies (299 ankles) did not address functional outcomes. Eleven studies (960 ankles) reported no association between heterotopic ossification and functional outcomes. One study (80 ankles) reported a statistically significant difference in range of motion (7°) and AOFAS score (7 points). In conclusion, although the incidence of heterotopic ossification after TAA is considerable, there is insufficient literature to suggest that heterotopic ossification after TAA impacts range of motion or functional outcome.

Effects of Cryopreserved Amniotic Membrane-Umbilical Cord Allograft on Total Ankle Arthroplasty Wound Healing.

Relatively high rates of wound healing complications continue to be reported with a total ankle arthroplasty (TAA) anterior incision. The amniotic membrane-umbilical cord (AM-UC) allograft is a regenerative orthobiologic adjunct that modulates wound healing by down-regulating inflammation, enhancing local healing and antimicrobial factors, and reducing scar formation. The purpose of this study was to determine whether local application of a cryopreserved AM-UC allograft enhances soft tissue healing after TAA. A total of 104 patients with symptomatic ankle arthritis who failed conservative management underwent standard TAA. At skin closure, patients were allocated to either the treatment (local application of AM-UC) or control (no allograft) group. Demographic data, patient comorbidities, and radiographic findings were collected. The primary outcome was a major complication necessitating reoperation. Secondary outcomes were time to healing, minor complications (i.e., skin dehiscence, local wound care, use of antibiotics), and patient scar assessment. Local application of an AM-UC allograft significantly decreased the overall time to skin healing (28.5 days vs 40 days; p = .03). Two patients required a reoperation for soft tissue wound complications, with no difference (p = 1.00) between the groups. No statistically significant difference was detected in terms of skin dehiscence, local wound care, or antibiotic prescriptions in the 2 groups. Regenerative technology using local application of a cryopreserved AM-UC allograft may enhance TAA outcomes by decreasing the time to healing. Larger randomized controlled trials are needed to determine whether an AM-UC allograft enhances soft tissue wound healing and ultimately reduces the incidence of devastating soft tissue complications.

Morbidity and Mortality in Elective Total Hip Arthroplasty Following Surgical Care Improvement Project Guidelines.

BACKGROUND: Following evidence questioning the safety and efficacy of perioperative beta-blocker therapy in noncardiac surgery, the Surgical Care Improvement Project (SCIP) guidelines were retired in 2015. However, perioperative myocardial infarctions and cardiac complications remain leading causes of mortality following noncardiac surgery. The impact of the SCIP guidelines on reducing cardiac complications in patients undergoing elective total hip arthroplasty (THA) has not been evaluated. METHODS: The Nationwide Inpatient Sample was queried for 345,875 elective THA performed from 2003 to 2011. Patient demographics and morbidity as well as the incidence of nonfatal and fatal cardiac complications and overall mortality associated with cardiac complications were determined before and following SCIP implementation. RESULTS: Following the institution of the SCIP guidelines, the overall mortality following cardiac complications decreased by 41%. Although the incidence of nonfatal cardiac events after THA did increase 5% (primarily secondary to an increased incidence of nonfatal hypotension), the incidence of postoperative inpatient mortality, stroke, fatal hypotension, fatal myocardial infarction, and nonfatal and fatal cardiac arrest significantly decreased. CONCLUSION: Following the implementation of SCIP guidelines, there was a 41% reduction in mortality and a significant decrease in fatal cardiac complications, postoperative hypotension, myocardial infarction, and cardiac arrest. Despite SCIP guidelines being retired in 2015, evidence supports continuation of perioperative beta-blockade in primary elective total adult hip and knee arthroplasty.

Morbidity and Mortality in Elective Total Knee Arthroplasty Following Surgical Care Improvement Project Guidelines.

BACKGROUND: Perioperative myocardial infarctions and cardiac complications are leading causes of mortality after noncardiac surgery. In an effort to improve patient safety, the Surgical Care Improvement Project (SCIP) implemented guidelines concerning administration of ß-blockers therapy aimed to reduce cardiac complications. METHODS: The Nationwide Inpatient Sample was queried for 759,819 elective total knee arthroplasties performed from 2003 to 2011. Incidence of cardiac complications, mortality, and risk factors for cardiac complications was determined before and after SCIP implementation. RESULTS: The incidence of cardiac events after total knee arthroplasty remained stable at 9%. The incidence and mortality of postoperative stroke, myocardial infarction, and cardiac arrest significantly decreased. Mortality after cardiac complications decreased by 50%. CONCLUSION: After the implementation of SCIP guidelines, there was a greater than 50% reduction in mortality and a significant decrease in fatal postoperative stroke, heart failure, and cardiac arrest.

Processing and Sectioning Undecalcified Murine Bone Specimens.

Preparation of mineralized tissue specimens for bone-specific staining encompasses a critical sequence of histological techniques that provides visualization of tissue and cellular morphology. Bone specimens are fixed in 10% neutral buffered formalin (NBF), dehydrated in graded ethanol (EtOH) solutions (and optionally cleared in xylene), infiltrated and embedded in polymethyl methacrylate (methyl methacrylate or MMA), classically sliced into 4-10 micrometer (µm) sections, and stained with bone-specific histological stains such as von Kossa (with either nuclear fast red solution counterstain or MacNeal's tetrachrome counterstain), modified Goldner's trichrome, Alizarin Red S, Safranin O, and tartrate-resistant acid phosphatase (TRAP) stain. Here, we describe the tissue processing of mineralized mouse bones from dissection to staining for histological analysis by light microscopy.

Blunt Thoracic Trauma-Induced Mitral Papillary Muscle Avulsion with Pericardial Rupture and Cardiac Herniation: Difficult and Delayed Diagnoses.

Blunt thoracic trauma (BTT) and the resultant isolated mitral papillary muscle avulsion, pericardial rupture, and cardiac herniation injuries are each rarely diagnosed clinical entities. We describe the first case of combined pericardial tear with cardiac herniation and ruptured mitral papillary muscles following BTT. Preoperative transesophageal echocardiography (TEE) diagnosed the delayed mitral papillary muscle rupture while all previous diagnostic modalities failed to delineate the pericardial rupture and cardiac herniation. Particular emphasis is placed on the clinical and radiologic aspects of the case that would heighten clinical suspicion in the emergency setting where blunt cardiac injury sequelae are suspected and frequently missed.

Clinical and Radiographic Outcomes of Revision Total Ankle Arthroplasty Using an Intramedullary-Referencing Implant.

BACKGROUND: Treatment of failed total ankle arthroplasty (TAA) is challenging. Limited literature is available on options and outcomes of revision arthroplasty despite failure rates ranging from 10% to 23% within 10 years after primary TAA. This study reports the clinical and radiographic outcomes of revision TAA using a fixed-bearing, intramedullary-referencing implant. METHODS: A retrospective review was performed of 18 consecutive revision TAA cases between 2008-2015 using an intramedullary-referencing, fixed-bearing, 2-component total ankle system. Demographic and radiographic data were collected preoperatively, immediately postoperatively, and at the most recent follow-up. Functional outcome data were collected immediately postoperatively and at mean follow-up 47.5 months. RESULTS: Eighteen patients underwent revision TAA, with 77.8% (14/18) implant survival. Index revision was performed most commonly for aseptic talar subsidence (55.6%) or implant loosening (tibia, 29.4%; talus, 58.9%). Following revision, 22.2% (4/18) patients required reoperation at a mean 57.3 (39-86) months. Osteolysis of the tibia, talus, and fibula was present preoperatively in 66.7% (12/18), 38.9% (7/18), and 38.9% (7/18) of patients, respectively, with progression of osteolysis in 27.8% (5/18), 11.1% (2/18) and 11.1% (2/18) of patients, respectively. Subsidence of the tibial and talar revision components was observed in 38.9% (7/18) and 55.6% (10/18) of patients, respectively. The median American Orthopaedic Foot & Ankle Society (AOFAS) score was 74.5 (26-100) and Foot Function Index (FFI) score 10.2 (0-50.4). CONCLUSION: Early results of intramedullary-referencing revision TAA demonstrated good patient-reported outcomes with maintenance of radiographic parameters at mean follow-up of 47.5 months. Aseptic talar subsidence or loosening were the main postoperative causes of reoperation. Revision arthroplasty utilizing an intramedullary-referencing implant was a viable option for the failed TAA. LEVEL OF EVIDENCE: Level IV, case series.

What Are the Indications for One-Stage Versus Two-Stage Exchange Arthroplasty in Management of the Infected Total Ankle Arthroplasty (TAA)?

RECOMMENDATION: Two-stage exchange arthroplasty is recommended in the majority of cases following infected TAA. One-stage arthroplasty is only indicated in a limited patient population with acute infection, preoperatively identified low-virulence organisms, and low-risk patient factors. LEVEL OF EVIDENCE: Consensus. DELEGATE VOTE: Agree: 92%, Disagree: 8%, Abstain: 0% (Super Majority, Strong Consensus).

What Strategies Can Be Implemented to Help Isolate the Causative Organism in Patients With Infection of the Foot and Ankle?

RECOMMENDATION: Transfer of synovial aspirate in blood culture bottles, obtaining deep biopsy of tissues and bone, obtaining multiple samples, increasing incubation period of cultures, and the use of molecular techniques for culture negative cases are some of the strategies that can help improve the ability to isolate the causative organism(s) in infections of foot and ankle. LEVEL OF EVIDENCE: Moderate. DELEGATE VOTE: Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

What Is the Treatment "Algorithm" for Infection After Ankle or Hindfoot Arthrodesis?

RECOMMENDATION: There is no universal algorithm for addressing the infected ankle or subtalar arthrodesis. A potential algorithm created by consensus is. LEVEL OF EVIDENCE: Consensus. DELEGATE VOTE: Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Tips and techniques for processing and sectioning undecalcified murine bone specimens.

Preparation of mineralized tissue specimens for bone-specific staining encompasses a critical sequence of histological techniques that provides visualization of tissue and cellular morphology. Bone specimens are fixed in 10 % neutral-buffered formalin, dehydrated in graded ethanol (EtOH) solutions (and optionally cleared in xylene), infiltrated and embedded in polymethyl methacrylate (methyl methacrylate), classically sliced into 4-10 micrometer (µm) sections, and stained with bone-specific histological stains such as von Kossa (with either nuclear fast red solution counterstain or MacNeal's tetrachrome counterstain), modified Goldner's trichrome, and alizarin red S stain. Here, we describe the tissue processing of mineralized mouse bones from dissection to staining for histological analysis by light microscopy.

A review of mouse critical size defect models in weight bearing bones.

Current and future advances in orthopedic treatment are aimed at altering biological interactions to enhance bone healing. Currently, several clinical scenarios exist for which there is no definitive treatment, specifically segmental bone loss from high-energy trauma or surgical resection - and it is here that many are aiming to find effective solutions. To test experimental interventions and better understand bone healing, researchers employ critical size defect (CSD) models in animal studies. Here, an overview of CSDs is given that includes the specifications of varying models, a discussion of current scaffold and bone graft designs, and current outcome measures used to determine the extent of bone healing. Many promising graft designs have been discovered along with promising adjunctive treatments, yet a graft that offers biomechanical support while allowing for neovascularization with eventual complete resorption and remodeling remains to be developed. An overview of this important topic is needed to highlight current advances and provide a clear understanding of the ultimate goal in CSD research--develop a graft for clinical use that effectively treats the orthopedic conundrum of segmental bone loss.