Suspected gluteal compartment syndrome: Etiology predicts clinical course, outcomes and resource utilization.

Background: Gluteal Compartment Syndrome (GCS) is a rare subtype of acute compartment syndrome (ACS), complex to diagnose and potentially fatal if left untreated. The incidence of ACS is estimated to be 7.3 per 100,000 in males and 0.

Does Anterior Plating of Pelvic Ring Fractures Increase Infection Risk in Patients With Bladder or Urethral Injuries?

Objectives: Evaluate the effect of anterior fixation on infection in patients with operative pelvic fractures and bladder or urethral injuries.

Design: Retrospective.

Setting: Eight centers.

Bicondylar Tibial Plateau Fractures: What Predicts Infection?

Objectives: The purpose of this study was to identify the patient, injury, and treatment factors associated with infection of bicondylar plateau fractures and to evaluate whether center variation exists.

Design: Retrospective review.

Setting: Eighteen academic trauma centers.

Proximal tibia fracture dislocations: Management and outcomes of a severe and under-recognized injury.

Introduction: Proximal tibia fracture dislocations (PTFDs) are a subset of plateau fractures with little in the literature since description by Hohl (1967) and classification by Moore (1981). We sought to evaluate reliability in diagnosis of fracture-dislocations by traumatologists and to compare their outcomes with bicondylar tibial plateau fractures (BTPFs).

Methods: This was a retrospective cohort study at 14 level 1 trauma centers throughout North America.

Acute Presentation of a Pseudoaneurysm After a Proximal Humerus Shaft Fracture: A Case Report.

Case: A 69-year-old woman presented with a brachial artery pseudoaneurysm causing median, ulnar, and radial nerve compressive neuropathies 8 weeks after a proximal humerus shaft fracture treated with intramedullary nailing. She underwent a brachial artery bypass with a reverse cephalic vein interposition graft and neurolysis after decompression of a large pseudoaneurysm. Postoperatively, the patient had a normal vascular examination with recovering neurological function.

Management of the Floating Knee: Ipsilateral Fractures of the Femur and Tibia.

The "floating knee" is defined as fractures of the ipsilateral femur and tibia, which consists of a spectrum of injury, and may be in isolation or part of multiple system trauma for a given patient. A floating knee may compromise limb viability due to severe soft-tissue and vascular injury. Expeditious fracture reduction and patient resuscitation are crucial, while type and timing of provisional and definitive management is guided by the extent of injury to the involved extremity and associated systemic injuries.

Wear Particle-induced Priming of the NLRP3 Inflammasome Depends on Adherent Pathogen-associated Molecular Patterns and Their Cognate Toll-like Receptors: An In Vitro Study.

Background: Orthopaedic wear particles activate the NLRP3 inflammasome to produce active interleukin 1β (IL1β). However, the NLRP3 inflammasome must be primed before it can be activated, and it is unknown whether wear particles induce priming. Toll-like receptors (TLRs) are thought to mediate particle bioactivity.

Catastrophic Failure of the Acetabular Polyethylene Liner in Ceramic-on-Polyethylene Total Hip Arthroplasty.

Introduction: Catastrophic polyethylene failure is a rare complication of ceramic-on-polyethylene total hip arthroplasty due to the favorable tribological characteristics of ceramic. Failure of the polyethylene liner can be disastrous, increasing periprosthetic osteolysis, metallosis, and risk of dislocation. Complications associated with ceramic-on-polyethylene articulations have been studied extensively, however, only few reports have described its catastrophic wear.

Posterior dislocation of the hinge-post extension in a rotating hinge total knee prosthesis.

The rotating hinge knee prosthesis is a popular intervention in patients lacking stability with highly constrained total knee arthroplasty. Despite improvements in design, nonmechanical and mechanical complications continue to be a problem. Dislocation of the hinge has been widely described, mainly due to the component fracture.

Nerve allografts and conduits in peripheral nerve repair.

Since the last update on nerve conduits and allograft in 2000, investigations have established the efficacy of these alternatives to autograft in the repair of small sensory neural gaps. However, limited insights into the biology of the regenerating nerve continue to preclude intelligent conduit design. Ongoing discoveries in neuroscience and biomaterial engineering hold promise for the eventual development of allograft and conduits with potential of surpassing nerve autografts in clinical efficacy.

Original article Muscle extracellular matrix degradation and contractibility following tendon rupture and disuse.

Muscle extracellular matrix (ECM) plays an important role in maintaining muscular integrity and force transduction. However, the role of ECM in skeletal muscle atrophy remains unknown. In this study, we employed two clinically relevant mouse models of Achillotenotomy and hindlimb suspension to simulate Achilles tendon rupture and hindlimb disuse.

Comparison of tissue oxygenation and compartment pressure following tibia fracture.

Objective: We investigated the ability of direct continuous measurement of intramuscular tissue oxygenation (PmO(2)) to detect acute ischaemia in the leg in patients at risk for acute extremity compartment syndrome. Following tibia fracture treated by intramedullary nailing, we compared the proportions of PmO(2) and compartment pressure (CP) measurements that met the warning criteria for compartment syndrome.

Methods: Participants included 10 patients sustaining acute isolated closed tibia shaft fractures treated by intramedullary nailing.

A mouse model of massive rotator cuff tears.

Background: Rotator cuff tears are the most common tendon injury seen in orthopaedic patients. Muscle atrophy and fatty infiltration in rotator cuff muscles are considered among the key factors responsible for the failure of attempted repair of a massive rotator cuff tear. However, the pathophysiology of rotator cuff muscle atrophy and fatty infiltration remains largely unknown, partly because of the lack of appropriate small animal models.

A rat model of massive rotator cuff tears.

Rotator cuff tears (RCTs) are the most common tendon injury seen in orthopedic patients. Massive RCT does not heal spontaneously and results in poor clinical outcomes. Muscle atrophy and fatty infiltration in rotator cuff muscles are major complications of chronic massive RCT and are thought to be the key factors responsible for the failure of attempted massive RCT repair.

Role of AP-1 and RE-1 binding sites in matrix metalloproteinase-2 transcriptional regulation in skeletal muscle atrophy.

Previous work has suggested that an extracellular matrix degrading enzyme-matrix metalloproteinase-2 (MMP-2) plays an important role in the development of muscle atrophy. However, the transcriptional regulation mechanism of MMP-2 in skeletal muscle atrophy remains largely unknown. Using transgenic MMP-2 promoter reporter mice, we have demonstrated that AP-1 and RE-1 binding sites in the MMP-2 promoter region, coupled with increased binding of Fra-1, Fra-2 and AP-2, play a critical role in MMP-2 transcriptional regulation in muscle atrophy.