Ideal xenograft or a perfect bone substitute?-A retrospective review and analysis of the historical concept of ivory implants in orthopaedics.

PURPOSE: Surgical treatment of fractures has evolved with the development of anaesthesia in 1846. Experiments with different implants both organic and non-organic had led to introduction of sometimes extremely peculiar materials coming from different species like ox bone or elephant's ivory. The aim of this article is to present not widely known concept of ivory use in bone surgery that set its foot in the history of orthopaedics and laid foundations for orthobiologic reconstructions. METHODS: Retrospective analysis of articles and books published between 1846 and 2017 that describe various examples of ivory application in the treatment of fresh fractures, non-unions and reconstruction of joints. RESULTS: Our research shows that ivory to the surgical world was introduced by Friedrich Dieffenbach, founder of the modern plastic surgery. It was also used with different rate of success by many of the famous surgeons of the nineteenth and twentieth century to include Trendelenburg, Billroth, Volkmann, Paget and Hey Groves. Ivory was immensely popular in bone surgery and became material of choice demonstrating amazing biological properties and very low rate of infections. CONCLUSION: Ivory has served well in successful treatment of various orthopaedic conditions for over 100 years. In this article, we are using history as a stepping stone to examine material that is not rejected by the body and promotes bony healing without increased infection or other complications. It is worth considering further analysis of historically acquired specimens for further development of materials for further orthopaedic fracture and reconstructive techniques.

Cationic Nanogel-mediated Runx2 and Osterix siRNA Delivery Decreases Mineralization in MC3T3 Cells.

BACKGROUND: Heterotopic ossification (HO) may occur after musculoskeletal trauma, traumatic brain injury, and total joint arthroplasty. As such, HO is a compelling clinical concern in both military and civilian medicine. A possible etiology of HO involves dysregulated signals in the bone morphogenetic protein osteogenic cascade. Contemporary treatment options for HO (ie, nonsteroidal antiinflammatory drugs and radiation therapy) have adverse effects associated with their use and are not biologically engineered to abrogate the molecular mechanisms that govern osteogenic differentiation. QUESTIONS/PURPOSES: We hypothesized that (1) nanogel-mediated short interfering RNA (siRNA) delivery against Runt-related transcription factor 2 (Runx2) and osterix (Osx) genes will decrease messenger RNA expression; (2) inhibit activity of the osteogenic marker alkaline phosphatase (ALP); and (3) inhibit hydroxyapatite (HA) deposition in osteoblast cell cultures. METHODS: Nanogel nanostructured polymers delivered siRNA in 48-hour treatment cycles against master osteogenic regulators, Runx2 and Osx, in murine calvarial preosteoblasts (MC3T3-E1.4) stimulated for osteogenic differentiation by recombinant human bone morphogenetic protein (rhBMP-2). The efficacy of RNA interference (RNAi) therapeutics was determined by quantitation of messenger RNA knockdown (by quantitative reverse transcription-polymerase chain reaction), downstream protein knockdown (determined ALP enzymatic activity assay), and HA deposition (determined by OsteoImage™ assay). RESULTS: Gene expression assays demonstrated that nanogel-based RNAi treatments at 1:1 and 5:1 nanogel:short interfering RNA weight ratios reduced Runx2 expression by 48.59% ± 19.53% (p < 0.001) and 43.22% ± 18.01% (both p < 0.001). The same 1:1 and 5:1 treatments against both Runx2 and Osx reduced expression of Osx by 51.65% ± 10.85% and 47.65% ± 9.80% (both p < 0.001). Moreover, repeated 48-hour RNAi treatment cycles against Runx2 and Osx rhBMP-2 administration reduced ALP activity after 4 and 7 days. ALP reductions after 4 days in culture by nanogel 5:1 and 10:1 RNAi treatments were 32.4% ± 12.0% and 33.6% ± 13.8% (both p < 0.001). After 7 days in culture, nanogel 1:1 and 5:1 RNAi treatments produced 35.9% ± 14.0% and 47.7% ± 3.2% reductions in ALP activity. Osteoblast mineralization data after 21 days suggested that nanogel 1:1, 5:1, and 10:1 RNAi treatments decreased mineralization (ie, HA deposition) from cultures treated only with rhBMP-2 (p < 0.001). However, despite RNAi attack on Runx2 and Osx, HA deposition levels remained greater than non-rhBMP-2-treated cell cultures. CONCLUSIONS: Although mRNA and protein knockdown were confirmed as a result of RNAi treatments against Runx2 and Osx, complete elimination of mineralization processes was not achieved. RNAi targeting mid- and late-stage osteoblast differentiation markers such as ALP, osteocalcin, osteopontin, and bone sialoprotein) may produce the desired RNAi-nanogel nanostructured polymer HO prophylaxis. CLINICAL RELEVANCE: Successful HO prophylaxis should target and silence osteogenic markers critical for heterotopic bone formation processes. The identification of such markers, beyond RUNX2 and OSX, may enhance the effectiveness of RNAi prophylaxes for HO.

Serotonin reuptake inhibitors and bleeding risks in major orthopedic procedures.

BACKGROUND: Risk of abnormal bleeding in surgery patients prescribed serotonin reuptake inhibitors (SRIs) is unclear. Considering the quantity of literature on abnormal gastrointestinal (GI) bleeding with SRIs, relatively little exists on SRI bleeding risks in surgical procedures. We investigated whether SRIs increase the risk of surgical bleeding in patients undergoing knee and hip total joint replacement. METHODS: RA retrospective case-control study was conducted among subjects undergoing primary total hip and knee replacement surgeries from January 2005 to March 2011 at a single institution. The experimental group was defined by utilization of SRIs at the time of surgery (the independent variable). The control group was matched for age, sex, ethnicity, and type of surgery (hip or knee). Any case with preoperative hematocrit <30, platelets <100,000; abnormal prothrombin time, partial-prothrombin time, and international normalized ratio (INR), primary bleeding disorder, medical conditions, or medications associated with increased bleeding was excluded. All cases were randomly selected. RESULTS: RA total of 194 subjects (hip 104, knee 90) were included. Statistical analysis was performed on the SRI group (n = 71) and the control, non-SRI group (n = 123). No difference was found between the groups in estimated blood loss, hemoglobin, hematocrit, platelets, PT, PTT, and INR from preoperative to postoperative day 1, 2, and 3. Furthermore, no subjects in either group required blood transfusions. CONCLUSION: SRIs were not associated with increased risk of bleeding in primary knee or hip replacement surgeries in this study. The hypothesis that SRIs increase the risk of bleeding based on presumptions about their action on platelet aggregation is uncertain and warrants further study.

Real-time intersession and interrater reliability of the functional movement screen.

The purpose of this study was to examine the real-time intersession and interrater reliability of the functional movement screen (FMS). The overall study consisted of 19 volunteer civilians (12 male, 7 female). The intersession reliability consisted of 12 men and 7 women, whereas 10 men and 6 women participated in the interrater reliability test session. Two raters (A and B) were involved in the interrater reliability aspect of this study. The FMS includes 7 tests: deep squat (DS), hurdle step (HS), in-line lunge (IL), shoulder mobility (SM), active straight leg raise (ASLR), trunk stability push-up (TSPU), and rotary stability (RS). Researchers analyzed the data via intraclass correlation (ICC). To determine the reliability of the intersession scoring of the FMS and the intrasession interrater scoring of the FMS a 2-way mixed effects model intraclass correlation coefficient (ICC(3,1)) was used for the continuous data, whereas a weighted Cohen's kappa (κ) was used for the categorical data. The dependent variables were FMS total score (0-21 scale) and associated tests were DS, HS, IL, SM, ASLR, TSPU, and RS. Intersession reliability (ICC, SEM) and κ were as follows: FMS total score (0.92, 0.51), DS (κ = 0.69), HS (κ = 0.16), IL (κ = 0.69), SM (κ = 0.84), ASLR (κ = 0.69), TSPU (κ = 0.77), and RS (no covariance). Interrater reliability (ICC, SEM) and κ were as follows: FMS total score (0.98, 0.25), DS (κ = 1.0), HS (κ = 0.33), IL (κ = 0.88), SM (κ = 0.90), ASLR (κ = 0.88), TSPU (κ = 0.75), and RS (no covariance). The FMS total scores displayed high intersession and interrater reliabilities. Finally, with the exception of HS, all tasks displayed moderate to high intersession reliability and good to high interrater reliability.

Effects of training on physical performance wearing personal protective equipment.

We evaluated the effects of wearing a weighted vest during 6 weeks of military-style training. Forty-three subjects were randomly assigned to a control group or a vest group (carrying 4-5 kg for 2 weeks, and 8-10 kg for 4 weeks), with 37 completing the study (17 vest, 20 control). Both groups performed stair climbing in addition to standard Marine Corps training for 1 hour, four times per week. Pre- and post-tests were performed while wearing military personal protective equipment, with the exception of the Marine Physical Readiness Test (PRT). Both groups significantly improved PRT scores (8.4% 3-mile run, 28-38% calisthenics) and an agility drill (4.4%). Significant improvements in uphill treadmill performance (6.8% vest, 3.0% control) and maximal oxygen consumption (10.7% vest, 6.8% control) were approximately twice as much in the vest versus control group, although these differences did not reach significance (p = 0.16 and 0.13, respectively).

Exercise and pregnancy.

Exercise is an important component of a healthy lifestyle and, as such, is recommended during pregnancy. However, the response to exercise of both the expectant mother and fetus varies depending on the fitness level of the woman. The response to exercise is also affected by the known musculoskeletal and physiologic changes associated with pregnancy, such as increased ligament laxity, weight gain, change in the center of gravity, and carpal tunnel syndrome. Although the physiologic responses of the pregnant woman and fetus have been well studied, the literature contains comparatively few studies investigating response to exercise. When performed properly, activities such as aerobics, impact and nonimpact activities, resistance training, and swimming may be beneficial during pregnancy.

Diagnosis and Treatment of Osteoporosis: What Orthopaedic Surgeons Need to Know.

Osteoporosis, often called a silent disease, is a systemic condition of bone as a result of loss of bone mass and deterioration of its microarchitecture. The result is weakened bone, leading to an increased risk of fragility fractures. An estimated 9 million osteoporotic fractures occur every year worldwide. However, the true incidence of osteoporotic fractures is unknown because many are undetected. Astoundingly, this epidemic equates to an osteoporotic fracture every 3 seconds. Orthopaedic surgeons need to not only treat these fractures but also understand the underlying pathogenesis and risk factors to help prevent them. The management of osteoporosis is a critical part of musculoskeletal care. We must be familiar with the tools to assess osteoporosis and the treatments available, including risks and benefits. This review article is intended to deliver a review of the vast literature and provide the orthopaedic surgeon with the essential information necessary to manage the current osteoporosis epidemic.

Teaching Professional Development to Orthopaedic Residents.

BACKGROUND: The traditional focus of residency training programs has been on the development of clinical and surgical skills. The expectation has been that nonclinical skills, including professional development, will be learned in an informal manner rather than through formal teaching. METHODS: After recognizing the absence of formal teaching on professional development in the residency curriculum, we developed a symposium to specifically address this omission. Topics included applying for fellowships, military promotions, overseas assignments, moonlighting, board certification, time management, lifelong orthopaedic learning, and finding a job after the military. Residents were surveyed before and after the symposium to determine the overall usefulness and value of the individual topics. RESULTS: All participating residents reported that they would recommend the symposium to other residents. The course received a mean overall rating of 4.64 (range, 4-5) on a on a scale from 1 (poor) to 5 points (excellent). High ratings were received for course usefulness, content, and relevance to future practice. CONCLUSIONS: A formal professional development program to address topics that are relevant to practice and learning should be integrated into an orthopaedic surgery residency curriculum.

Understanding and preventing noncontact anterior cruciate ligament injuries: a review of the Hunt Valley II meeting, January 2005.

The incidence of noncontact anterior cruciate ligament injuries in young to middle-aged athletes remains high. Despite early diagnosis and appropriate operative and nonoperative treatments, posttraumatic degenerative arthritis may develop. In a meeting in Atlanta, Georgia (January 2005), sponsored by the American Orthopaedic Society for Sports Medicine, a group of physicians, physical therapists, athletic trainers, biomechanists, epidemiologists, and other scientists interested in this area of research met to review current knowledge on risk factors associated with noncontact anterior cruciate ligament injuries, anterior cruciate ligament injury biomechanics, and existing anterior cruciate ligament prevention programs. This article reports on the presentations, discussions, and recommendations of this group.

Evaluation of bone surrogates for indirect and direct ballistic fractures.

The mechanism of injury for fractures to long bones has been studied for both direct ballistic loading as well as indirect. However, the majority of these studies have been conducted on both post-mortem human subjects (PMHS) and animal surrogates which have constraints in terms of storage, preparation and testing. The identification of a validated bone surrogate for use in forensic, medical and engineering testing would provide the ability to investigate ballistic loading without these constraints. Two specific bone surrogates, Sawbones and Synbone, were evaluated in comparison to PMHS for both direct and indirect ballistic loading. For the direct loading, the mean velocity to produce fracture was 121 ± 19 m/s for the PMHS, which was statistically different from the Sawbones (140 ± 7 m/s) and Synbone (146 ± 3 m/s). The average distance to fracture in the indirect loading was .70 cm for the PMHS. The Synbone had a statistically similar average distance to fracture (.61 cm, p=0.54) however the Sawbones average distance to fracture was statistically different (.41 cm, p<0.05). Fractures patterns were found to be comparable to the PMHS for tests conducted with Synbones, however the input parameters were slightly varied to produce similar results. The fractures patterns with the Sawbones were not found to be as comparable to the PMHS. An ideal bone surrogate for ballistic testing was not identified and future work is warranted.

Predictors of Revision Surgery After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Arthroscopically assisted anterior cruciate ligament (ACL) reconstruction is a common orthopaedic procedure. Graft failure after reconstruction remains a devastating complication, often requiring revision surgery and less aggressive or modified rehabilitation. Worse functional and patient-reported outcomes are reported compared with primary reconstruction. Moreover, both rates and risk factors for revision are variable and inconsistent within the literature. PURPOSE: To determine the rate of revision surgery after ACL reconstruction in a large cohort of patients, to assess the influence of patient characteristics on the odds of revision, and to compare revision rates between active-duty military members and non-active-duty beneficiaries. STUDY DESIGN: Descriptive epidemiology study. METHODS: Using administrative data from the Military Health System, a retrospective study was designed to characterize the rate of ACL revision surgery among patients treated within a military facility. All patients ≥18 years at the time of ACL reconstruction were identified using the American Medical Association Current Procedural Terminology (CPT) for ACL reconstruction (CPT code 29888) over 7 years (2005-2011). Revision ACL reconstructions were identified as having ≥2 ACL reconstruction procedure codes on the ipsilateral knee at least 90 days apart. Univariate analysis was performed to calculate odds ratios (ORs) for demographic, perioperative medication use, and concomitant procedure-related risk factors. A multivariate logistic regression model determined risk covariates in the active-duty cohort. RESULTS: The study population consisted of 17,164 ACL reconstructions performed among 16,336 patients, of whom 83.3% were male with a mean ± SD age of 28.9 ± 7.6 years for the nonrevision group, and was predominantly active duty (89.2%). Patients undergoing ACL reconstruction on both knees only contributed their index knee for analyses. There were 587 patients who underwent revision surgery, corresponding to an overall revision rate of 3.6%. The median time from the index surgery to revision surgery was 500 days (interquartile range, 102-2406 days). Revision rates were higher in the active-duty cohort as compared with non-active-duty beneficiaries (3.8% vs 1.8%, respectively; OR, 2.14; 95% CI, 1.49-3.07). Based on multivariate logistic regression in the active-duty cohort, age ≥35 years (OR, 0.44; 95% CI, 0.33-0.58) and concomitant meniscal repair (OR, 0.69; 95% CI, 0.53-0.91) were found to be protective with regard to the odds of revision surgery. Perioperative medication use of nonsteroidal anti-inflammatory drugs (NSAIDs) (OR, 1.33; 95% CI, 1.12-1.58; number needed to harm [NNH], 100) and COX-2 inhibitors (OR, 1.31; 95% CI, 1.04-1.66; NNH, 333) was associated with increased odds of revision surgery. No significant findings were detected among sex, race, nicotine use, body mass index, or other concomitant procedures of interest. CONCLUSION: In this large cohort study, the rate of revision ACL reconstruction was 3.6%, which is consistent with the existing literature. Increased odds of revision surgery among active-duty personnel were associated with the perioperative use of NSAIDs and COX-2 inhibitors. Age ≥35 years and concomitant meniscal repair were found to be protective against ACL revision.

The Prevalence of Symptomatic Deep Venous Thrombosis and Pulmonary Embolism After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Arthroscopically assisted anterior cruciate ligament (ACL) reconstruction is a common orthopaedic procedure. The incidence and risk factors of venous thromboembolism (VTE) after ACL reconstruction remain unclear. PURPOSE: To define the incidence of VTE after ACL reconstruction and identify associated risk factors in a large cohort of patients. STUDY DESIGN: Descriptive epidemiological study. METHODS: All patients aged ≥18 years who underwent ACL reconstruction between 2005 and 2011 were identified from the Department of Defense Medical Data Repository. The prevalence of VTE, including deep venous thrombosis (DVT) and pulmonary embolism (PE), within 3 months of ACL reconstruction was queried. Univariate analyses were performed to define odds ratios (ORs) for demographic, medication use, and procedural-related risk factors. RESULTS: A total of 87 VTE events (0.53% [95% CI, 0.42%-0.65%]) occurred after 16,558 ACL reconstructions performed on 15,767 patients. DVT was documented after 55 procedures and PE after 35 procedures. Three patients were documented to have both DVT and PE within the study period. The odds of VTE increased in patients aged ≥35 years (OR, 1.96 [95% CI, 1.27-3.04]; P = .003). Nicotine history increased the odds of DVT (OR, 1.99 [95% CI, 1.15-3.43]; P = .014). Concomitant high tibial osteotomy (HTO) increased the odds of PE (OR, 18.31 [95% CI, 2.4-139.6]; P = .005), whereas concomitant posterior cruciate ligament (PCL) reconstruction increased the odds of both VTE (OR, 3.43 [95% CI, 1.07-11.2]; P = .38) and DVT (OR, 5.57 [95% CI, 1.71-18.14]; P = .004). Nonsteroidal drug use was associated with decreased odds for VTE and DVT (OR, 0.44 [95% CI, 0.28-0.70]; P < .001 and OR, 0.38 [95% CI, 0.22-0.69]; P < .001, respectively). Anticoagulants were associated with increased odds for VTE, DVT, and PE (OR, 98.32 [95% CI, 61.63-156.86]; P < .001; OR, 111.93 [95% CI, 63.95-195.92]; P < .001; and OR, 47.84 [95% CI, 22.55-101.52]; P < .001, respectively). No detectible difference in odds was found for sex, body mass index, or aspirin or cyclooxygenase-2 inhibitor use. CONCLUSION: The incidence of VTE after ACL reconstruction in this large population was low. Increased odds of VTE was identified in patients aged ≥35 years with a history of nicotine use, anticoagulant use, concomitant HTO, or concomitant PCL reconstruction. Controlled studies are necessary to determine the efficacy of chemoprophylaxis and to develop evidence-based clinical practice guidelines to minimize VTE after ACL reconstruction.

A novel technique for ligamentous reconstruction of the sternoclavicular joint.

SUMMARY: The technique presented is a departure from previous attempts to standardize the treatment of sternoclavicular dislocations. It offers stability without requiring extra dissection around vital intrathoracic structures and greatly decreases the risk of migration of the implant used for fixation.