Biomechanical Properties of Nitinol Staples: Effects of Troughing, Effective Leg Length, and 2-Staple Constructs.

PURPOSE: Nitinol memory compression staples are a recent addition to carpal bone fixation. Compared with traditional staples, they have been shown to have superior compression at the far cortex relative to standard and traditional compression staples. The purpose of this study was to (1) determine the effective leg length of different nitinol staples, (2) confirm the effect of 1 versus 2 staples on biomechanical compression, and (3) determine the effect of troughing (countersinking the staple into bone) the bone on staple biomechanical properties. METHODS: Three commonly used nitinol staples of various bridge and leg lengths were used in a bicortical sawbones block construct. There were 3 separate constructs tested, which included single staple, double staple, and troughed. We measured compression force, stiffness, and bending strength for each construct before and after cyclical 4-point bending. Compression mapping was used to determine the effective leg length of each staple, which included the distance that compression extended beyond the tips of the staple legs. RESULTS: Effective leg length for each staple construct extended 2 mm distal to the tip of the shortest staple leg. Two staple constructs more than doubled compressive force and increased bending strength by greater than 90% in all staple types. There was no loss of compressive force before or after loading for single, double, or troughed constructs with any staple type. CONCLUSIONS: This study supports that nitinol staples do not have to be placed bicortically to achieve adequate compression; placing staples 2 mm short of the far cortex has the same compression as bicortical placement; and troughing of the bone will not significantly diminish the biomechanical properties of the construct. CLINICAL RELEVANCE: Better understanding of the effective leg length of nitinol staples provides support that bicortical placement is not necessary for adequate compression. This study supports troughing bone to minimize implant prominence.

Scaphoid Fractures in Adults Aged 50 Years or Older: Epidemiology and Association With Osteopenia and Nonunion.

BACKGROUND: Scaphoid fractures are less commonly reported in adults older than 50 years. The association between bone density and outcomes following scaphoid fractures has not been explored in this patient population. The second metacarpal cortical percentage (2MCP) has been shown to predict low bone density. The purpose of this study is to describe the epidemiology and radiographic characteristics associated with scaphoid fractures in adults older than 50 years, determine the prevalence of osteopenia defined by 2MCP, and evaluate the characteristics associated with scaphoid nonunion in this population. We hypothesized that osteopenia defined by 2MCP would be common in this patient population and associated with scaphoid nonunion. METHODS: Patients older than 50 years with an acute, closed scaphoid fracture were identified. Demographic data, radiographic characteristics, and outcome data were collected. The 2MCP was measured using standard hand radiographs. RESULTS: A total of 111 patients were identified. Most fractures were nondisplaced and occurred in women via low-energy mechanism. Fifty-six patients (50.5%) had osteopenia defined by a 2MCP less than 60%. Nondisplaced fractures achieved union faster than displaced fractures (P < .05). Displaced, unstable fractures were statistically associated with nonunion (P < .001). 2MCP did not correlate with nonunion. CONCLUSIONS: In adults older than 50 years, scaphoid fractures may represent a fragility fracture cohort given they occur more frequently in female patients via low-energy mechanisms and over half of the cohort had osteopenia defined by a 2MCP less than 60%. Displaced and unstable fractures were statistically more likely to go on to nonunion. Nonunion was not found to be associated with osteopenia.

Retrospective Comparison of Capitolunate Arthrodesis Using Headless Compression Screws Versus Nitinol Memory Staples for SLAC and SNAC Wrist: Radiographic, Functional, and Patient-Reported Outcomes.

BACKGROUND: Nitinol memory compression staples have been proposed as an effective alternative to compression screws for capitolunate arthrodesis (CLA) for scaphoid nonunion advanced collapse (SNAC) and scapholunate advanced collapse (SLAC) wrist. The purpose of this study was to compare the clinical outcomes of CLA for SNAC or SLAC wrist treatment using either compression screws or nitinol staples. METHODS: In all, 47 patients with CLA for SLAC or SNAC wrist with screws or nitinol staples were retrospectively identified. Primary outcome was fusion on radiographs and/or computed tomography. Secondary outcomes were hardware-related complications (HWCs) and other complications, range of motion, grip strength, and patient-reported outcome measures (PROMs), including Visual Analogue Pain scale; Disabilities of the Arm, Shoulder, and Hand score; and patient-rated wrist evaluation. RESULTS: Of the 47 eligible patients, 40 (85%) were included: 31 patients in the staple group and 9 patients in the screw group. The average age was 49 (17-80) years. There was an 89% union rate for the screw group and a 97% union rate for the staple group. Two patients had screw backout: one who went onto union after screw removal and the other who went onto nonunion after hardware removal. There were 2 (6.5%) HWCs in the staple group. One patient had staple loosening requiring revision and the other dorsal impingement requiring staple removal after radiographic union. In all subsequent cases, the staples were countersunk with no impingement. No significant differences existed between any additional outcomes. CONCLUSIONS: We found no differences between nitinol staples and screws for CLA regarding HWCs or PROMs. Nitinol staples may offer additional benefits as a safe and effective alternative to compression screws for wrist fusions.

Screws-Only Primary Subtalar Arthrodesis for Calcaneus Fractures.

BACKGROUND: The management of displaced intraarticular calcaneus fractures (DIACFs) is a difficult problem with disappointing results from open reduction internal fixation (ORIF). Alternatively, ORIF with primary subtalar arthrodesis (PSTA) has gained increasing popularity. The purpose of this study is to review patient-centered and radiographic outcomes of ORIF plus PSTA using only screws through a sinus tarsi approach. METHODS: A retrospective study of patients who underwent ORIF+PSTA for DIACFs was conducted. The same surgical technique was used in all cases consisting of only screws; no plates were used. Delayed surgeries past 8 weeks were excluded. Demographic and radiographic data were collected including worker's compensation claims. Plain radiographs were used to characterize injuries and review outcomes. RESULTS: Seventy-nine DIACFs underwent PSTA with a median follow-up of 200 days (n = 69 patients). Median time to weightbearing was 57.5 days postoperatively. Ten fractures were documented as Sanders II, 36 as Sanders III, and 32 as Sanders IV. Sixty-eight fractures (86.1%) achieved fusion on radiographs at a median of 126.5 (range, 54-518) days. Thirty-nine fractures (57.3%) demonstrated radiographic fusion in all 3 predefined locations. Nine of the 14 worker's compensation patients returned to work within the period of observation. There were 8 complications: 3 requiring a secondary operation. Eleven of 79 fractures treated did not go on to achieve radiographic union. CONCLUSION: In this retrospective case series, we found that screws-only primary subtalar arthrodesis for the treatment of DIACFs through a sinus tarsi approach was associated with relatively high rates of return to work and radiographic fusion. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Sternoclavicular Septic Arthritis Caused by Cutibacterium acnes in a Previously Healthy 13-Year-Old Male: A Case Report.

CASE: A 13-year-old boy presented with 3 weeks of atraumatic left-sided sternoclavicular (SC) joint pain, swelling, and decreased range of motion. After imaging and laboratory workup, he underwent operative irrigation, debridement, and antibiotic therapy with complete resolution of his symptoms. Surgical cultures were consistent with SC septic arthritis. CONCLUSION: The management of septic arthritis in pediatric patients remains varied. Here, we present the only report of SC septic arthritis due to Cutibacterium acnes in a healthy pediatric patient. Given the similar clinical findings of pain and swelling to affected bones and joints, differentiating SC septic arthritis from other conditions within the clinical spectrum of chronic nonbacterial osteomyelitis remains challenging. Clinicians should maintain a high index of suspicion when patients present with pain and swelling over the SC joint.

Quality and Content of Internet-Based Information for Osteoporosis and Fragility Fracture Diagnoses.

INTRODUCTION: We aimed to assess the quality and content of websites addressing orthopaedic conditions affecting older adults, emphasizing osteoporosis and fragility fracture. METHODS: Ten diagnoses were chosen. The transparency of information was assessed via the Health On the Net (HON) score; information content was assessed via diagnosis-specific grading templates. A total of 140 websites (14 per diagnosis) were reviewed by three raters. HON scores and information quality were compared by diagnosis, website type, and website source. The correlation between HON score and information quality score was calculated. RESULTS: Most websites were commercial (59.3%). Cronbach alpha for Hall scores exceeded the a priori threshold of 0.7. Analysis proceeded using averages across raters. HON score was significantly associated with higher content scores (r = 0.56; P < 0.0001). Content scores ranged from 21.1 to 59.4. Content scores differed significantly by diagnosis (P = 0.0008) and website source (P < 0.0001). DISCUSSION: The quality and content of websites is highly variable for osteoporosis and fragility fracture diagnoses. Patients should be encouraged to access reputable sites, including sites displaying a HON seal. Academic and medical specialty societies demonstrate opportunity for improvement of their own websites and might be able to lead efforts to increase accessibility of high-quality content.

Virtual Reality and Augmented Reality-Translating Surgical Training into Surgical Technique.

PURPOSE OF REVIEW: As immersive learning outside of the operating room is increasingly recognized as a valuable method of surgical training, virtual reality (VR) and augmented reality (AR) are increasingly utilized in orthopedic surgical training. This article reviews the evolving nature of these training tools and provides examples of their use and efficacy. The practical and ethical implications of incorporating this technology and its impact on both orthopedic surgeons and their patients are also discussed. RECENT FINDINGS: Head-mounted displays (HMDs) represent a possible adjunct to surgical accuracy and education. While the hardware is advanced, there is still much work to be done in developing software that allows for seamless, reliable, useful integration into clinical practice and training. Surgical training is changing: AR and VR will become mainstays of future training efforts. More evidence is needed to determine which training technology translates to improved clinical performance. Volatility within the HMD industry will likely delay advances in surgical training.

Surgical Approaches to the Proximal Humerus: A Quantitative Comparison of the Deltopectoral Approach and the Anterolateral Acromial Approach.

BACKGROUND: Debate exists over the optimal approach for addressing fractures of the proximal humerus. The purpose of this study was to objectively quantify the surface area of the humerus exposed using the deltopectoral (DP) and anterolateral acromial (ALA) approaches and to compare visualized and palpable anatomic landmarks. METHODS: Ten arms on five fresh-frozen torsos underwent the DP and ALA approaches. The arms were positioned to simulate a supine patient and held in a fixed position. Visual and/or palpable access to relevant surgical landmarks and the myotendinous junctions were recorded. The myotendinous junctions were used as a rough approximation of consistent proximal exposure of a clinically retracted tuberosity. Landmarks were grouped into quadrants based on the location. Calibrated digital photographs of each approach were analyzed to calculate the surface area and the length of the exposed bone. RESULTS: The DP and ALA approaches exposed 22.9 ± 6.3 cm2 and 16.3 ± 6.4 cm2, respectively (P = 0.03). The DP and ALA approaches provided equivalent visual and palpable access to all landmarks in the superior and inferior quadrants. The ALA allowed improved visual (80% versus 70%) and palpable (100% versus 70%) access to the myotendinous junction of the infraspinatus in the posterior quadrant. The DP approach allowed better access to anterior quadrant structures, including improved ability to visualize the myotendinous junction of the subscapularis (100% versus zero), the subscapularis insertion (100% versus 80%), and the medial anatomic neck (100% versus 20%). Palpable access to the myotendinous junction of the subscapularis (100% versus 70%) and medial anatomic neck (100% versus 60%) was also improved with the DP. CONCLUSIONS: In a cadaver model with fixed arm position, the DP provides increased exposure to the proximal humerus and more reliable access to anterior surgical landmarks, whereas the ALA allows improved access to the most posterior aspect of the shoulder.