Comparison of reamer irrigator aspirator (RIA) suspension versus bone marrow aspirate concentrate (BMC) for percutaneous treatment of long bone nonunions-A preclinical canine model.

OBJECTIVE: To compare the bone healing effects of percutaneously delivered bone marrow aspirate concentrate (BMC) versus reamer irrigator aspirator (RIA) suspension in a validated preclinical canine ulnar nonunion model. We hypothesized that BMC would be superior to RIA in inducing bone formation across a nonunion site after percutaneous application. The null hypothesis was that BMC and RIA would be equivalent. METHODS: A bilateral ulnar nonunion model (n= 6; 3 matched pairs) was created. Eight weeks after segmental ulnar ostectomy, RIA from the ipsilateral femur and BMC from the proximal humerus were harvested and percutaneously administered into either the left or right ulnar defect. The same volume (3 ml) of RIA suspension and BMC were applied on each side. Eight weeks after treatment, the dogs were euthanized, and the nonunions were evaluated using radiographic, biomechanical, and histologic assessments. RESULTS: All dogs survived for the intended study duration, formed radiographic nonunions 8 weeks after segmental ulnar ostectomy, and underwent the assigned percutaneous treatment. Radiographic and macroscopic assessments of bone healing at the defect sites revealed superior bridging-callous formation in BMC-treated nonunions. Histologic analyses revealed greater amount of bony bridging and callous formation in the BMC group. Biomechanical testing of the treated nonunions did not reveal any significant differences. CONCLUSION: Bone marrow aspirate concentrate (BMC) had important advantages over Reamer Irrigator Aspirator (RIA) suspension for percutaneous augmentation of bone healing in a validated preclinical canine ulnar nonunion model based on clinically relevant radiographic and histologic measures of bone formation.

Characterization of regional variation of bone mineral density in the geriatric human cervical spine by quantitative computed tomography.

BACKGROUND: Odontoid process fractures are among the most common in elderly cervical spines. Their treatment often requires fixation, which may include use of implants anteriorly or posteriorly. Bone density can significantly affect the outcomes of these procedures. Currently, little is known about bone mineral density (BMD) distributions within cervical spine in elderly. This study documented BMD distribution across various anatomical regions of elderly cervical vertebrae. METHODS AND FINDINGS: Twenty-three human cadaveric C1-C5 spine segments (14 males and 9 female, 74±9.3 y.o.) were imaged via quantitative CT-scan. Using an established experimental protocol, the three-dimensional shapes of the vertebrae were reconstructed from CT images and partitioned in bone regions (4 regions for C1, 14 regions for C2 and 12 regions for C3-5). The BMD was calculated from the Hounsfield units via calibration phantom. For each vertebral level, effects of gender and anatomical bone region on BMD distribution were investigated via pertinent statistical tools. Data trends suggested that BMD was higher in female vertebrae when compared to male ones. In C1, the highest BMD was found in the posterior portion of the bone. In C2, BMD at the dens was the highest, followed by lamina and spinous process, and the posterior aspect of the vertebral body. In C3-5, lateral masses, lamina, and spinous processes were characterized by the largest values of BMD, followed by the posterior vertebral body. CONCLUSIONS: The higher BMD values characterizing the posterior aspects of vertebrae suggest that, in the elderly, posterior surgical approaches may offer a better fixation quality.

Biomechanical Analysis of Conventional Partially Threaded Screws Versus Headless Compression Screws in Proximal Fifth Metatarsal (Jones) Fracture Fixation.

BACKGROUND: Intramedullary screw fixation of Jones fractures using partially threaded screws is a common method of fixation for these injuries, but refracture continues to be a problem. Various other fixation strategies, such as headless compression screws, plantar plating, and tension-band wiring. have been developed to mitigate these issues. Biomechanical studies with regard to these other fixation strategies are limited. Herein, we investigate the compression strength and angular stiffness of Jones fractures fixed with Herbert-style headless compression screws. METHODS: Jones fractures were created in 10 fresh-frozen pairs of cadaveric fifth metatarsals. A bone from each pair was instrumented with either a conventional, partially threaded screw 5.0 or 6.5 mm in diameter, or a headless compression screw 5.0 or 7.0 mm in diameter. Sizes were determined via sequential tapping until a snug fit was obtained. Each metatarsal was stressed via cantilever bending over 1000 cycles. We monitored compression and displacement throughout. RESULTS: Headless compression screws achieved a significantly higher amount of stiffness than conventional, partially threaded screws (P = 0.005). There was no statistically significant difference with respect to compression. CONCLUSION: In a cadaveric model, headless compression screws achieved a greater amount of fracture stiffness versus conventional, partially threaded screws.Levels of Evidence: Therapeutic, Level V: Biomechanical.

Outcomes of Lisfranc Injuries Treated with Joint-Preserving Fixation.

BACKGROUND: Open reduction and internal fixation (ORIF) with transarticular screws to stabilize Lisfranc injuries may increase the risk of arthritis or affect outcomes. Joint-preserving fixation using staples, bridge plating, or Lisfranc screws avoids iatrogenic articular damage. This study analyzes functional outcomes and complications in Lisfranc-injury patients who underwent joint-preserving fixation. MATERIALS AND METHODS: We conducted a retrospective review of patients treated for Lisfranc injury at a Level 1 trauma center from July 2008 to October 2015. Patients over 18 years of age, with no concomitant procedures in the lower extremities, were included. Functional outcomes were evaluated through American Orthopaedic Foot and Ankle Society (AOFAS) scores. RESULTS: Fourteen patients met the inclusion criteria. The average followup time was 57 months (range 22-102 months). AOFAS scores averaged 80.4 (standard deviation [SD] 16) at the time of the latest followup, with time to return to regular activities averaging 34 weeks (SD 25 weeks). Five patients had their hardware removed, and two required subsequent fusion during the followup period. The single complication involved a screw backing out, with subsequent removal. CONCLUSIONS: In this case series, joint-preserving fixation for Lisfranc injuries offered similar AOFAS scores as those reported for ORIF with transarticular screws but with a decreased rate of hardware removal and need for midfoot fusion.

Efficacy of a Urinary Bladder Matrix for Treating Wound Dehiscence With Hardware Exposure in a Patient With Rheumatoid Arthritis.

OBJECTIVE: This case report explores an effective treatment modality in a medically complicated patient, with considerable wound dehiscence refractory to treatment with negative pressure wound therapy (NPWT). CASE REPORT: A 35-year-old woman with a past medical history of hypothyroidism, osteoporosis, and rheumatoid arthritis treated with tumor necrosis factor (TNF) alpha inhibitors and disease-modifying antirheumatic drugs presented to the clinic following right great toe arthrodesis, metatarsal neck osteotomies, extensor tendon lengthening, and capsulotomy of the second, third, fourth, and fifth toes 2 weeks prior, with wound dehiscence of the right great toe and subsequent exposure of surgical hardware, complicated by infection. At the 2-week postop, a urinary bladder matrix was placed on the wound following failed NPWT, which was in place for 10 days. At the 3-month follow-up, the wound was closed and without any drainage. Patient reported a significant reduction in pain (visual analogue scale: 3) with adherence to weight-bearing restrictions. CONCLUSIONS: Wound healing was accomplished without removal of the exposed deep hardware in a patient with comorbidities and post-surgical wound dehiscence.

Lessons Learned: Deformity Correction and Tibiotalocalcaneal Arthrodesis in a Patient With Glanzmann Thrombasthenia: A Case Report.

CASE: A 33-year-old woman with Glanzmann thrombasthenia presented to us with a distal tibia nonunion. We attempted to treat her with a multiplanar ring external fixator, but the patient was unable to tolerate the correction, so we resorted to a tibiotalocalcaneal fusion. Hemostasis was difficult to achieve despite the use of antithrombinolytics, factor VII, and platelet transfusions. CONCLUSION: Bleeding can be difficult to control in patients with Glanzmann thrombasthenia. However, overaggressive preadministration of antithrombinolytics should be avoided because it may have adverse effects such as acrocyanosis. The presence of thrombasthenia does not seem to affect the success of arthrodesis.

Idiopathic Peroneal Tenosynovitis Caused by a Previously Undiagnosed Auto-immune Condition.

In this case report, we present a unique case of idiopathic peroneal tenosynovitis in an otherwise healthy patient, presenting with a three-month history of pain over the lateral aspect of the right foot. Imaging revealed that fluid distention and synovial thickening distend the common peroneal tendon sheath and peroneus longus and brevis tendon sheaths. The patient was managed operatively with excision of the peroneus longus tendon, a side-to-side tenodesis, and Bröstrom-Gould lateral ankle ligament repair. Histologic examination was suggestive of a chronic inflammatory process possibly due to underlying autoimmune etiology. At three-month follow-up, the patient reported complete resolution of pain and is resuming normal activities without difficulty.

Biomechanics of aerial righting in wingless nymphal stick insects.

Numerous wingless arthropods as well as diverse vertebrates are capable of mid-air righting. We studied the biomechanics of the aerial righting reflex in first-instar nymphs of the stick insect Extatosoma tiaratum. After being released upside-down, insects reoriented dorsoventrally and stabilized body posture via active modulation of limb positions and associated aerodynamic torques. We identified specific reflexes for bilaterally asymmetric leg displacements which elicit body rotation and subsequently stabilize mid-air posture. Coordinated appendicular movements thus improve torsional manoeuvrability in the absence of wings, as may have characterized the initial origins of controlled aerial behaviour in arthropods. Design of small aerial or multimodal robotic vehicles may similarly benefit from use of such strategies for flight control.

Comparison Between Tc-99m WBC SPECT/CT and MRI for the Diagnosis of Biopsy-proven Diabetic Foot Osteomyelitis.

OBJECTIVE: Magnetic resonance imaging (MRI) is the recommended diagnostic imaging technique for diabetic foot osteomyelitis (DFO), with a reported accuracy of 79%. The gold standard to diagnose osteomyelitis is bone biopsy, with a positive culture and/or histopathology findings consistent with osteomyelitis. The purposes of this study are to assess the accuracy of technetium-99m (Tc-99m) labeled white blood cell (WBC) single-photon emission computed tomography/computed tomography (SPECT/CT) hybrid imaging for diagnosing DFO confirmed by bone biopsy and to compare that to the diagnostic accuracy of an MRI. MATERIALS AND METHODS: The authors performed a retrospective chart review of 166 patients who received a bone biopsy to confirm the diagnosis of a suspected DFO at a large municipal hospital between 2010 and 2013. Patients were selected on the basis of whether they received an MRI or a SPECT/CT. Patients whose scans were not within a clinically relevant time frame of the biopsy were excluded. Imaging results were correlated with probability of osteomyelitis determined by bone biopsy. RESULTS: For inclusion criteria, 110 patients met the study's criteria: 52 SPECT/CT patients and 58 MRI patients. The sensitivity, specificity, positive predictive value, and negative predictive value of SPECT/CT were 89%, 35%, 74%, and 60%, respectively; the corresponding values for MRI were 87%, 37%, 74%, and 58%, respectively. There were no significant differences in accuracy of diagnosing DFO between imaging techniques. CONCLUSION: This data suggests that the diagnostic accuracy of SPECT/CT imaging in DFOs is similar to an MRI.

Diagnostic Accuracy of Probe to Bone to Detect Osteomyelitis in the Diabetic Foot: A Systematic Review.

The probe-to-bone (PTB) test is a commonly used clinical test for osteomyelitis (OM), but its utility has been questioned in clinical settings where the prevalence of OM is low. This article aims to systematically review the accuracy of the PTB test to diagnose diabetic foot OM. We searched Ovid Medline and Scopus databases for studies using the keywords "probe to bone," "osteomyelitis," and "diabetic foot" from 1946 to May 2015. We summarized characteristics of the included studies and pooled the accuracy numbers using a bivariate random-effects model. Seven studies met our inclusion criteria. Pooled sensitivity and specificity for the PTB test was 0.87 (95% confidence interval [CI], .75-.93) and 0.83 (95% CI, .65-.93), respectively. We conclude that the PTB test can accurately rule in diabetic foot OM in the high-risk patients and rule out OM in low-risk patients.

Senior Medical Student-Led Interactive Small-Group Module on Acute Fracture Management.

INTRODUCTION: Medical students receive insufficient training in musculoskeletal diagnosis and management. To address this deficiency, a senior medical student at our institution designed and moderated small-group interactive discussions with third-year medical students on acute fracture management during their family medicine clerkship. METHODS: In these sessions, students learned how to diagnose and comprehensively work up a case of a suspected fracture, how to effectively communicate findings from physical exam and X-ray, and when to appropriately consult a surgeon for treatment. RESULTS: This module was piloted with a total of 14 students in two separate small groups. One hundred percent of students regarded the module as very useful, and there was a 50% improvement in pre- versus posteducational assessment. DISCUSSION: Our experience suggests that students can quickly improve clinical skills for fracture management in a focused smallgroup interactive session. In addition, these sessions can be effectively designed and implemented by senior medical students. This module may be used with either clinical or preclinical students, but we believe that this information would be best received by clinical students on family medicine, emergency medicine, or orthopedic rotations.

Establishing the need for family medicine training in intimate partner violence screening.

In 2012, the USPSTF updated its guidelines and now recommends that all women of childbearing age be screened for IPV and services provided for women who screen positive. Based on these recommendations, objectives of this study were to (1) evaluate IPV knowledge, attitudes, and practices of physicians from different specialties and (2) determine significant differences by medical specialty. We recruited (n = 183) Internal Medicine, Emergency Medicine, Family Medicine (FM) and Obstetrics/Gynecology (OB/GYN) residents and attending physicians to complete a 15-question online survey assessing knowledge, attitudes and current IPV screening practices. We evaluated associations between medical specialty and knowledge, attitudes and practice measures before and after controlling for covariates. Knowledge of how often IPV occurs in society, community resources, and screening tools were significantly different by specialty (all p's < 0.05). A majority of FM physicians (88%) reported that it is a physician's responsibility to find and treat IPV and 97% reported that IPV should be included in their training. Compared to OB/GYN physicians in multivariate analyses, FM physicians were less likely to report they were comfortable discussing IPV with their patients in crude (OR = 0.35; 95% CI = 0.13, 0.94) and adjusted models (OR = 0.20; 95% CI = 0.06, 0.60). FM physicians were also less likely to report screening female patients for IPV before (OR = 0.25; 95% CI = 0.08, 0.86) and after adjusting for confounders (OR = 0.11; 95% CI = 0.03, 0.47). Our results indicate that FM physicians have positive attitudes towards finding and treating IPV yet need enhanced training to improve their comfort level with screening for and discussing IPV with their patients.