Diabetes as a Risk Factor for Orthopedic Implant Surface Performance: A Retrieval and In Vitro Study.

Orthopedic devices are often associated with increased risk for diabetic patients due to impaired wound healing capabilities. Adverse biological responses for immunocompromised patients at the implant-tissue interface can lead to significant bone resorption that may increase failure rates. The goal of this study was to characterize the surface of implants removed from diabetic patients to determine underlying mechanisms of diabetes-induced impaired osseointegration. Thirty-nine retrieved titanium and stainless-steel orthopedic devices were obtained from diabetic and non-diabetic patients, and compared to non-implanted controls. Optical Microscopy, Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, and X-ray Photoelectron Spectroscopy revealed changes in morphology, chemical composition, oxidation state, and oxide thickness of the retrieval specimens, respectively. Additionally, titanium disks were immersed for 28 days in simulated in vitro diabetic conditions followed by Inductively Coupled Plasma-Optical Emission Spectroscopy to quantify metal dissolution. Electrochemical testing was performed on specimens from retrievals and in vitro study. Aside from biological deposits, retrievals demonstrated surface discoloration, pit-like formations and oxide thinning when compared to non-implanted controls, suggesting exposure to unfavorable acidic conditions. Cyclic load bearing areas on fracture-fixation screws and plates depicted cracking and delamination. The corrosion behavior was not significantly different between diabetic and non-diabetic conditions of immersed disks or implant type. However, simulated diabetic conditions elevated aluminum release. This elucidates orthopedic implant failures that potentially arise from diabetic environments at the implant-tissue interface. Design of new implant surfaces should consider specific strategies to induce constructive healing responses in immunocompromised patients while also mitigating corrosion in acidic diabetic environments.

Comparison of Interscalene Brachial Plexus Block Performed With and Without Steroids.

This prospective comparative clinical study was performed to evaluate the effect of triamcinolone when added to bupivacaine during brachial plexus blockade in patients undergoing shoulder surgery. Interscalene brachial plexus blocks were performed on 910 patients before shoulder surgery. Of the patients, 574 were randomly allocated to receive steroids added to the injected local anesthetic and 336 patients received local anesthetic without steroids. All patients were followed prospectively to evaluate the rate of successful anesthesia, duration of anesthesia, side effects of the block, adverse events, and persistent neurologic complications associated with interscalene brachial plexus block. Patients who received steroids had statistically longer pain relief than those who did not receive steroids (P<.001). No difference was found in adverse events, complications, or side effects. Compared with blocks performed without steroids, a statistically longer duration of block analgesia occurred with the addition of steroids to the local anesthetic solution during brachial plexus blockade. Rates of side effects, adverse events, and persistent neurologic complications were similar between the groups. [Orthopedics. 2016; 39(6):e1100-e1103.].

Asymptomatic Migration of a Kirschner Wire from the Proximal Aspect of the Humerus to the Thoracic Cavity: A Case Report.

CASE: A 78-year-old man presented with an open fracture of the proximal aspect of the humerus and an axillary artery laceration; the fracture was treated provisionally with Kirschner wires (K-wires). Forty-five days postoperatively, he presented with pin prominence at the lateral aspect of the arm, and was incidentally noted to have migration of a separate K-wire to the left lung. He underwent successful thoracotomy and lung wedge resection for wire removal. CONCLUSION: K-wires used in the fixation of fractures of the proximal aspect of the humerus may migrate into the thoracic cavity. No modification of this technique, including the use of threaded, terminally bent, or external pins that are visibly secured, eliminates the potential for devastating complications.

Arthroscopic anterior cruciate ligament reconstruction using a flexible guide pin with a rigid reamer.

Successful anterior cruciate ligament reconstruction depends heavily on accurate placement of the graft within the anatomical insertion of the native anterior cruciate ligament. Inaccurate placement can lead to graft failure and recurrent instability. Flexible guide pins and reamers have been developed to overcome some of the limitations of using transtibial and anteromedial portals to drill femoral tunnels. Early in our experience with flexible instruments, reamer breakage caused complications. We therefore developed a technique that uses a flexible guide pin with a rigid reamer to place the femoral tunnel in an anatomical position. This technique allows placement of longer anatomical tunnels through an anteromedial portal, reduces time spent with the knee in hyperflexion, provides better viewing, poses less risk of damage to the articular cartilage and neurovascular structures, and at a lower cost with less risk of reamer breakage.

Pseudoaneurysm after arthroscopic subacromial decompression and distal clavicle excision.

Arthroscopic shoulder surgery is considered a safe and effective method of treating a variety of shoulder pathologies and is associated with a low complication rate. The type and rate of complications can vary, depending on the procedure, positioning, surgical time, and anesthesia. Fortunately, neurovascular injuries occur infrequently. Numerous studies have described the proximity of neurovascular structures to portals placed in shoulder arthroscopy, in both the beach chair and the lateral decubitus positions. Accurate portal placement is important to avoid damage to adjacent neurovascular structures. Inaccurate placement of portals can lead to inadvertent damage to these structures and create more difficulty with visualization and angle of instrumentation, possibly compromising the success of the procedure. This article describes a 50-year-old man who underwent arthroscopic subacromial decompression and distal clavicle excision for persistent subacromial impingement and acromioclavicular arthritis. During postoperative follow-up, the patient had a small, bulging area located near the anterior portal site. Examination showed a well-healed anterior portal site with a small (approximately 2×2 cm), nontender, immobile mass located within the deep soft tissues just below the anterior portal incision. Ultrasound evaluation showed a pseudoaneurysm of a branch off the axillary artery. The patient underwent successful embolization of the pseudoaneurysm, with complete resolution of symptoms.

Gymnastic wrist injuries.

During gymnastic activities, the wrist is exposed to many different types of stresses, including repetitive motion, high impact loading, axial compression, torsional forces, and distraction in varying degrees of ulnar or radial deviation and hyperextension. Many of these stresses are increased during upper extremity weight-bearing and predispose the wrist to high rates of injury during gymnastics. Distal radius stress injuries are the most common and most documented gymnastic wrist conditions. Other conditions include scaphoid impaction syndrome, dorsal impingement, scaphoid fractures, scaphoid stress reactions/fractures, capitate avascular necrosis, ganglia, carpal instability, triangular fibrocartilage complex tears, ulnar impaction syndrome, and lunotriquetral impingement. It is important to diagnose quickly and accurately the specific injury to initiate expediently the proper treatment and limit the extent of injury. In addition, a gymnast's training regimen should also include elements of injury prevention.

Proximal femoral stress reaction in a professional football player.

There have been no previous case reports of femoral stress fractures in professional football players. We present a professional defensive back who presented 1 week after noting mild soreness in the right proximal thigh during practices, prior to a regular season game. Early diagnosis of a stress reaction was made with magnetic resonance imaging (MRI). Magnetic resonance imaging is an excellent imaging modality for stress reactions/fractures given its high sensitivity, specificity, and ability to image surrounding soft tissues. Short tau inversion recovery and fat-suppressed images are best for seeing early osseous edema. Early detection of this injury allowed us to hasten the recovery and prevent further injury. The patient was treated successfully with early nonweight bearing, a gradual increase in activity via cross training, and a structured functional progression to return to play. Normalization of MRI lagged behind the player's healing and was not necessary to determine advancement of rehabilitation or return to play. Three main issues are important to review in this case of a proximal femoral stress injury: early diagnosis is the key to treatment and early return to play; imaging studies lag behind clinical symptoms; and the treatment regimen should consist of a period of rest and be tailored to the individual.

Risk factors in total joint arthroplasty: comparison of infection rates in patients with different socioeconomic backgrounds.

Infection after total joint arthroplasty is a serious complication. Several risk factors have been shown to increase the risk of total joint infections. The purpose of this study was to evaluate whether socioeconomic background was a risk factor for infection in primary total joint arthroplasty. A retrospective chart review was conducted over a 4-year period on a single surgeon's split practice between private patients with mostly private insurance and Medicare and county based patients with predominately indigent county health coverage and Medicaid. An infection rate was calculated for each population in both primary total knee and hip arthroplasty. The two populations were statistically analyzed for differences in age, preoperative diagnoses, and socioeconomic background. To our knowledge, this is the first study showing an increased risk of infection in total joint arthroplasty based on socioeconomic background.