The clinical use of allografts, demineralized bone matrices, synthetic bone graft substitutes and osteoinductive growth factors: a survey study

The emergence of new bone grafting options and alternatives has led to significant uncertainty when determining the most appropriate product for surgical procedures requiring bone graft in orthopedics. Allografts, demineralized bone matrices, synthetic bone graft substitutes, and osteoinductive growth factors are all viable options, yet there is a lack of data reporting clinical usage of these products. This correspondence reports on the use of bone grafting products at the Hospital for Special Surgery for a 27-month period and makes recommendations based on surgical usage, safety, and cost. Approximately half (48.6%) of all bone graft substitutes were implanted during spinal surgery. Arthroplasty, trauma, and foot/hand cases all used considerable amounts of bone grafting products as well (20.1%, 19.0%, 12.1%, respectively). Considerable differences were noticed in usage of bone grafting products among each orthopedic discipline. Of all bone graft substitutes used in arthroplasty, 14.4% were demineralized bone matrices, whereas 56.8% were allografts. Demineralized bone matrix grafts were used in 82% of trauma surgery and 89% of foot/hand cases. An increase in synthetic bone graft alternatives was noticed near the end of our investigation period.

Identification of the radial nerve during the posterior approach to the humerus: a cadaveric study

OBJECTIVE

Identification of the radial nerve is necessary during the posterior approach to the humerus in an effort to maintain its integrity. Other than anatomic descriptions of the radial nerve with respect to osseous structures, there are few superficial intraoperative landmarks along the course of the traditional triceps-splitting approach to provide facile nerve identification. The objective of this study was to determine the reliability of using the anatomic intersection of the long and lateral heads of the triceps and the triceps aponeurosis as a superficial reference point for radial nerve identification during the posterior approach to the humerus.

METHODS

Thirty adult human cadaver upper extremities as 15 matched pairs were used. Systematic identification and measurement from the point of intersection between the long and lateral heads of the triceps and the triceps aponeurosis to the distal most aspect of the radial nerve as it coursed the posterior humerus at its midaxial point was performed and recorded.

RESULTS

Mean distance was found to measure 39.0 ± 2.1 mm (range, 36-44 mm), approximating a fixed distance, two finger breadths proximal to our identified point of intersection. Statistical analysis between the two matched pair groups yielded no significant difference in measured distances (P = 0.88).

CONCLUSIONS

Our group has identified the point of intersection among three landmarks forming a point of intersection. This point is the confluence of the long and lateral heads of the triceps and the triceps aponeurosis. This serves as a visualized anatomic reference point during the posterior surgical exposure to the humerus and can be used to identify the radial nerve as it courses the posterior humerus.

Coronal Shear Fractures of the Distal Humerus: A Review of Diagnosis, Treatment, and Outcomes

Fractures of the capitellum and trochlea are uncommon fractures of the elbow and can be challenging to treat due to their size, location, and articular nature. Because of their intra-articular nature and predilection toward displacement, these fractures are typically treated operatively. Furthermore, capitellum fractures have high rates of associated injuries, including radial head fractures or lateral collateral ligament injury in ~30% to 60% of patients. In addition to open reduction internal fixation, operative options include fragment excision, arthroscopic assisted reduction and fixation, and elbow arthroplasty. In this article, we undertake a comprehensive literature review of capitellum fractures of the distal humerus, in an attempt to summarize the existing body of evidence and propose areas of future study.

Treatment Outcomes in Patients Undergoing Surgical Treatment for Arthritis of the Distal Radioulnar Joint

Objective  Surgical treatment options for distal radioulnar joint (DRUJ) arthritis include distal ulnar resection (DUR), DRUJ arthrodesis, and ulnar head replacement. Ulnar convergence leading to persistent pain and clicking is a relatively common complication of complete DUR and DRUJ arthrodesis with distal ulnar segment resection (DRUJA). This led to the development of the distal ulna hemiresection (DUHR) and distal ulnar stump stabilization techniques to reduce the risk of this complication. Patients may experience incomplete relief of pain and limited range of motion (ROM) with these procedures. We hypothesized that there would be no differences in outcomes between the treatment groups, but patients undergoing DUHR, tendon interposition, or distal ulnar stump stabilization would be at lower risk of complications. Methods  Records were retrospectively reviewed for 121 patients undergoing DRUJ procedures between 2000 and 2018 at a single institution to collect patient demographics, surgical details, preoperative diagnosis, and outcomes including complications, revision procedures, ROM, pain, and swelling. Patients were grouped for analysis by procedure type: DUR (Darrach procedure), DUHR (Bowers procedure), and DRUJA (Sauve-Kapandji procedure). Continuous variables were compared using an analysis of variance test and categorical variables using the Freeman-Halton extension of the Fisher's exact test. A multivariate logistic regression analysis was performed to identify significant predictors of outcomes. Results  Seventy-three patients underwent a DUR procedure, while 33 patients underwent a DUHR procedure and 11 underwent a DRUJA procedure. Mean follow-up was 70.6 months. Patients undergoing DRUJA were significantly younger than those undergoing DUR or DUHR procedure (42.4 vs. 60.0 vs. 62.1, p  < 0.001). No significant differences between groups were demonstrated in measured outcomes. Posttraumatic arthritis was the most common preoperative diagnosis (43.4%). Persistent pain was the most common negative outcome (25.6%) followed by limited ROM (19.7%). Five patients (4.3%) suffered postoperative complications, most common being rupture of extensor tendons. Five patients (4.3%) underwent revision procedures. Body mass index (BMI) was a significant predictor of persistent pain (odds ratio = 1.09, p  = 0.031). Conclusion  The results of our study suggest that outcomes are equivalent between the three distinct treatment groups. Despite the potential benefits, hemiresection, tendon interposition, and distal stump stabilization had no significant effect on outcomes in this study. More than a quarter (25.6%) of patients undergoing DRUJ procedures experience persistent pain postoperatively, while one-fifth (19.7%) experienced limited ROM. Patients with higher BMI are at a significantly greater risk of experiencing persistent postoperative pain. Level of Evidence  This is a Level III, retrospective comparative study.

Vibrio parahaemolyticus growth under low-iron conditions and survival under high-magnesium conditions

Since 1996, Vibrio parahaemolyticus serotype O3:K6 and closely related strains have been associated with an increased incidence of V. parahaemolyticus gastroenteritis worldwide, suggesting the emergence of strains with enhanced abilities to cause disease. One hypothesis for the recent emergence of V. parahaemolyticus O3:K6 and related strains is an enhanced capacity for environmental survival relative to other strains, which might result in increased human exposure to these organisms. Therefore, the objective of this study was to test the hypothesis that survival or growth characteristics of clinical V. parahaemolyticus isolates differ from those of nonclinical isolates under different environmental conditions. Twenty-six V. parahaemolyticus isolates selected to represent either clinical or food sources were monitored for either survival following exposure to high magnesium (300 mM) or growth under iron-limited conditions. Isolates in each category (clinical or food) differed widely in survival capabilities following 24 h of exposure to 300 mM Mg2+. Although 4 of 15 clinical isolates grew better at approximately 0.96 microM Fe2+ (iron-limited conditions) than at 50 microM Fe2+ (iron-rich conditions), as an entire group clinical isolates in this study were not more effective at growing under iron-limited conditions than were strains not associated with disease. Within the diverse collection of strains examined in these experiments, neither growth characteristics in low-iron environments nor survival capabilities following exposure to high magnesium concentrations were uniformly different between clinical and nonclinical V. parahaemolyticus isolates. Therefore, neither phenotypic characteristic can be used to reliably differentiate potentially pathogenic V. parahaemolyticus strains.

A Comparison of Two Sterile Solution Application Methods During Surgical Preparation of the Hand

PURPOSE

The purpose of this study was to determine the extent of skin coverage during surgical preparation of the hand when preparation is done by 2 different methods. We hypothesized that hand preparation with commercially available prep-stick applicators (PS) would lead to more unprepared areas (UPAs) of skin compared with immersed 4 × 4 inch sterile gauze sponges (GS) used as controls.

METHODS

Sixty upper extremities of 30 healthy volunteers were used for this study. The hands were prepped by 2 fellowship trained orthopedic hand surgeons as 30 matched pairs. The experimental group was prepped using a commercially available PS (ChloraPrep, Carefusion, San Diego, CA), whereas the control group was prepared with GS immersed in the prep solution and applied manually using sterile gloves. The number and location of UPAs in the hands and wrists of volunteers after preparation were recorded. In addition, the sum of UPAs relative to the total surface area of the skin was quantified with image analysis software.

RESULTS

There were a total of 77 UPAs when prepping the volunteers with PS, compared with 14 in the control hands. This difference was statistically significant. Similarly, the average percentage area of UPAs relative to the total skin surface was 0.76% (range, 0.006% to 2.15%) when using PS compared with 0.15% (range, 0.005% to 0.56%) in the controls. This difference was statistically significant.

CONCLUSIONS

We identified a larger numbers of UPAs with commercially available applicator sticks compared with a control using sterile GS.

CLINICAL RELEVANCE

The clinical implications of these findings are unknown.

Diagnosis and Management of Common Hand Infections

While many hand infections are superficial, diligent evaluation, diagnosis, and treatment of these infections are central for preventing disability and morbidity. Maintaining a wide differential diagnosis is important as some hand infections may mimic others. In geographic areas with more than a 10% to 15% prevalence of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) hand infections, empiric antibiotics should adequately cover MRSA. Once culture results are available, antibiotic regimens should be narrowed to reduce the development of resistant pathogens.

Acute Septic Carpal Tunnel Syndrome in a Rock Climber

Introduction:

Rock climbing is an increasingly popular sport in the United States. Acute and chronic upper extremity injuries related to rock climbing are frequently reported and include flexor pulley ruptures and hamate stress fractures. Deep space hand infections after indoor rock climbing are a sport-related pathology that has yet to be reported. Our purpose is to describe an acute septic carpal tunnel syndrome following rock climbing at an indoor climbing gym in a patient who required urgent irrigation and debridement.

Case Report:

A 33-year-old Caucasian male presented with an acute septic carpal tunnel syndrome 4 days after rock climbing at an indoor gym. On physical examination, he exhibited numbness over the fingers, significant tenderness to palpation, and pain with passive range of motion. His inflammatory markers were markedly elevated and deep space hand infection was confirmed with computed tomography scans. The patient was taken for urgent exploration, irrigation and debridement, and carpal tunnel release.

Conclusion:

We theorize that the patient had an abrasion on the finger or palm that created an entryway for a pathogen. We are unaware of another report of a deep space hand infection associated with rock climbing activities. This case report will hopefully spread awareness of this clinical entity to improve evaluation and prevention of hand infections in rock climbers, as well as providing guidelines for appropriate and timely treatment of the condition.

Reliability of Routine Radiographs for Conservatively Treated Metacarpal Shaft and Neck Fractures

Background

To investigate the reliability of orthopedic hand surgeons to evaluate radiographic healing in initial and follow-up radiographs of the conservatively treated metacarpal shaft and neck fractures. The rationale for this study was to reduce the rate of unnecessary, routine radiographs when treating metacarpal fractures.

Methods

Forty sets of digital x-rays, twenty at the initial visit and twenty at the 4-week follow-up, were randomly selected and reviewed. Three hand surgeons evaluated the x-rays for (1) fracture location, (2) radiograph timing, (3) healing status, (4) percentage healed, (5) angulation, and (6) confidence in healing status. Observers reviewed studies in random order and evaluated the same set of radiographs one month after the initial review. Intra- and interobserver agreements were analyzed using Fleiss' kappa (κ) for all parameters and all possible observer pairings.

Results

Interobserver and intraobserver reliability was highest when evaluating fracture location and lowest when assessing the percentage healed. The interobserver reliability was fair for radiograph timing and healing status and fair-to-moderate for angulation. The intraobserver reliability was moderate for radiograph timing and healing status and moderate-to-substantial for angulation. Observers correctly differentiated initial vs. follow-up images 62% of the time and reported to feel somewhat certain in their evaluation of healing status.

Conclusion

When evaluating initial and 4-week follow-up radiographs, hand surgeons were somewhat confident in their assessment of healing but had less than substantial intra- and interobserver reliability following radiographic evaluation. Due to their poor reproducibility, routine radiographs may be unnecessary when evaluating conservatively treated metacarpal fractures. Further studies and guidelines that identify clear indications for the use of routine imaging in metacarpal fracture care are warranted.