The Relationship Between Obesity and Lateral Condyle Fracture Healing: A Pilot Study.

OBJECTIVE: Childhood obesity is a growing public health concern in the United States. Obesity has been shown to lead to increased complications with regards to orthopaedic injuries, such as more severe fracture patterns, notably observed in injuries like lateral condyle fractures of the humerus. However, there is currently a gap in the literature regarding the relationship between obesity and the healing potential of these fractures. This study aims to determine whether obesity is associated with increased surgical time, wound/pin site infections, delayed union/nonunion, and time to union in pediatric patients with lateral condyle fractures of the humerus. METHODS: A retrospective chart review was conducted at a level 1 trauma center on all patients 18 years or younger who sustained a lateral condyle fracture of the humerus. Patients were stratified into groups based on their body mass index-for-age percentile as defined by the Centers for Disease Control and Prevention; normal weight (<85%), overweight (85 to <95%), and obese (≥95%). Demographic data, Weiss classification, postoperative complications (infection, delayed union or nonunion, malunion, and need for repeat surgery), length of surgery, and time to union were recorded. Comparisons of categorical data were analyzed using χ2 tests. Analysis of variance was used to compare the means between weight cohorts for continuous data. RESULTS: A total of 123 patients were analyzed. Sixty-six were categorized as normal weight, 20 were overweight, and 37 were obese. There were no significant differences between weight classes for any complications, including infection, delayed/nonunion, malunion, or repeat surgery. There was no correlation with fracture severity as defined by the Weiss classification of lateral condyle fractures in regards to weight cohort (P = 0.098). There was no significant difference in length of surgery (P = 0.393) or average time to union (P = 0.236) between the weight cohorts. CONCLUSION: In this study, population with higher pediatric obesity rates than the population average, there was no significant correlation between body mass index-for-age and each of the surgical complications reviewed, length of surgery, or time to union, indicating the healing potential of lateral condyle fractures in obese pediatric patients is no more compromised than that of their normal weight peers. LEVEL OF EVIDENCE: Level III-a retrospective study.

A pilot hole does not reduce the strains or risk of fracture to the lateral cortex during and following a medial opening wedge high tibial osteotomy in cadaveric specimens.

AIM: It has been suggested that the use of a pilot-hole may reduce the risk of fracture to the lateral cortex. Therefore the purpose of this study was to determine the effect of a pilot hole on the strains and occurrence of fractures at the lateral cortex during the opening of a high tibial osteotomy (HTO) and post-surgery loading. MATERIALS AND METHODS: A total of 14 cadaveric tibias were randomized to either a pilot hole (n = 7) or a no-hole (n = 7) condition. Lateral cortex strains were measured while the osteotomy was opened 9 mm and secured in place with a locking plate. The tibias were then subjected to an initial 800 N load that increased by 200 N every 5000 cycles, until failure or a maximum load of 2500 N. RESULTS: There was no significant difference in the strains on the lateral cortex during HTO opening between the pilot hole and no-hole conditions. Similarly, the lateral cortex and fixation plate strains were not significantly different during cyclic loading between the two conditions. Using a pilot hole did not significantly decrease the strains experienced at the lateral cortex, nor did it reduce the risk of fracture. CONCLUSIONS: The nonsignificant differences found here most likely occurred because the pilot hole merely translated the stress concentration laterally to a parallel point on the surface of the hole.Cite this article: K. Bujnowski, A. Getgood, K. Leitch, J. Farr, C. Dunning, T. A. Burkhart. A pilot hole does not reduce the strains or risk of fracture to the lateral cortex during and following a medial opening wedge high tibial osteotomy in cadaveric specimens. Bone Joint Res 2018;7:166-172. DOI: 10.1302/2046-3758.72.BJR-2017-0337.R1.

Changes in biomechanical risk factors for knee osteoarthritis and their association with 5-year clinically important improvement after limb realignment surgery.

OBJECTIVE: To evaluate 5-year outcomes after lower limb realignment and test the hypothesis that surgery-induced changes in selected biomechanical risk factors for medial knee osteoarthritis (OA) are associated with clinically important improvements. DESIGN: We prospectively evaluated patient-reported outcomes, full-limb standing radiographs and gait biomechanics before, 6 months (surgery-induced change) and 5 years after medial opening wedge high tibial osteotomy (HTO) in 170 patients (46.4 ± 8.9 years, 135 males) with knee OA and varus alignment. Logistic regression tested the associations of 6-month changes in mechanical axis angle and knee adduction moment with achieving an increase of ≥10 points in the Knee injury and Osteoarthritis Outcome Score (KOOS)4 at 5 years, with and without adjusting for covariates. Gait data were also compared to existing data from healthy controls. RESULTS: Mean 5-year changes (95% confidence interval (CI)) were: KOOS4: +14.2 (10.8, 17.6); mechanical axis angle: +8.21° (7.58, 8.83); knee adduction moment: -1.49 %BW*Ht (-1.35, -1.63). The postoperative knee adduction moments were typically lower than values for healthy controls. When divided into quartiles, although all strata improved significantly, patients with reductions in knee adduction moment of 1.14-1.74 %BW*Ht (neither largest nor smallest changes) had highest 5-year KOOS4 scores. The 6-month change in knee adduction moment (odds ratios (OR) = 0.38; 95% CI: 0.22, 0.67), preoperative KOOS4 (OR = 0.96; 95% CI: 0.94, 0.99) and preoperative medial tibiofemoral narrowing grade (OR = 0.62; 95% CI: 0.37, 1.00) were negatively associated with having a 5-year clinically important improvement (C-statistic = 0.70). CONCLUSIONS: Substantial improvements in biomechanical risk factors and patient-reported outcomes are observed 5 years after medial opening wedge HTO. The surgery-induced change in load distribution during walking is significantly associated with long-term clinically important improvement.

Biomechanical effects of valgus knee bracing: a systematic review and meta-analysis.

To review and synthesize the biomechanical effects of valgus knee bracing for patients with medial knee osteoarthritis (OA). Electronic databases were searched from their inception to May 2014. Two reviewers independently determined study eligibility, rated study quality and extracted data. Where possible, data were combined into meta-analyses and pooled estimates with 95% confidence intervals (CI) for standardized mean differences (SMD) were calculated. Thirty studies were included with 478 subjects tested while using a valgus knee brace. Various biomechanical methods suggested valgus braces can decrease direct measures of medial knee compressive force, indirect measures representing the mediolateral distribution of load across the knee, quadriceps/hamstring and quadriceps/gastrocnemius co-contraction ratios, and increase medial joint space during gait. Meta-analysis from 17 studies suggested a statistically significant decrease in the external knee adduction moment (KAM) during walking, with a moderate-to-high effect size (SMD = 0.61; 95% CI: 0.39, 0.83; P < 0.001). Meta-regression identified a near-significant association for the KAM effect size and duration of brace use only (ß, -0.01; 95% CI: -0.03, 0.0001; P = 0.06); with longer durations of brace use associated with smaller treatment effects. Minor complications were commonly reported during brace use and included slipping, discomfort and poor fit, blisters and skin irritation. Systematic review and meta-analysis suggests valgus knee braces can alter knee joint loads through a combination of mechanisms, with moderate-to-high effect sizes in biomechanical outcomes.

The effect of walking poles on the knee adduction moment in patients with varus gonarthrosis.

OBJECTIVES: (1) Test the hypothesis that walking poles decrease the external knee adduction moment during gait in patients with varus gonarthrosis, and (2) explore potential mechanisms. DESIGN: Thirty-four patients with medial compartment knee osteoarthritis (OA) and varus alignment underwent three dimensional (3D) gait analysis with and without using walking poles. Conditions were randomized and walking speed was maintained ±5% of the self-selected speed of the initial condition. The pole held in the hand of the unaffected side was instrumented with a compression load cell. RESULTS: Student's t tests for paired samples indicated small but statistically significant increases (P < 0.001) in knee adduction moment (calculated from inverse dynamics) for its first peak, second peak and angular impulse when using the poles; mean increases (95% confidence interval - CI) were 0.17%BW*Ht (0.08, 0.27), 0.17%BW*Ht (0.04, 0.30) and 0.15%BW*Ht*s (0.09, 0.22), respectively. There was a decrease (P = 0.015) in vertical ground reaction force (-0.02 BW (-0.04, -0.01)), yet increase (P < 0.001) in its frontal plane lever arm about the knee (0.30 cm (0.15, 0.44)), at the time of the first peak knee adduction moment. Pole force in the vertical direction was inversely related (r = -0.34, P = 0.05) to the increase in first peak adduction moment. CONCLUSION: Although results are variable among patients, and may be related to individual technique, these overall findings suggest that walking poles do not decrease knee adduction moments, and therefore likely do not decrease medial compartment loads, in patients with varus gonarthrosis. Decreases in knee joint loading should not be used as rationale for walking pole use in these patients.

Suitability of three saws for minimally invasive bone cutting.

This study compares 3 different saw types to determine which is best suited for integration into a minimally invasive bone saw. A handheld electric jigsaw, a coping saw, and a Gigli saw were used to cut into porcine ilium. Heat generated was measured using a thermocouple, and forces applied during cutting were recorded using a force/torque sensor. The coping saw generated an average maximum temperature that was 26 degrees C less than that generated using the jigsaw (P < .001) and 14 degrees C less than that for the Gigli saw (P < .001). On average, the maximum force applied through the coping saw was 14 N less than that through the jigsaw (P < .001) and 18 N less than that through the Gigli saw (P < .001). Out of the 3 saws tested, the coping saw is optimal for cutting bone based on heat generation and required force.

Lemierre's syndrome with septic shock caused by Fusobacterium necrophorum.

Fusobacterium necrophorum infections are rare. We report a 15-year-old male who presented with tachycardia, nausea, vomiting, diarrhoea and ankle pain. He rapidly deteriorated requiring ventilation and vasopressors. Imaging of his thorax showed airspace consolidation, pulmonary cavitations and empyema. The ankle required drainage of purulent material. A thrombus in his internal jugular vein (Lemierre's syndrome) and an abscess in his obturator internus were subsequently found. Fusobacterium necrophorum was identified in blood culture on day nine. The patient recovered with antibiotics and surgical interventions for empyema and septic arthritis. Fusobacterium necrophorum should be a suspected pathogen in septic shock complicated by metastatic abscess formation.

Treatment of multidirectionally unstable supracondylar humeral fractures in children. A modified Gartland type-IV fracture.

BACKGROUND: There is an uncommon subset of supracondylar humeral fractures in children that are so unstable they can displace into both flexion and extension. The purposes of this study were to describe this subset of supracondylar fractures and to report a new technique of closed reduction and percutaneous pinning for their treatment. METHODS: In a retrospective review of 297 consecutive displaced supracondylar humeral fractures in children treated operatively at our institution, we identified nine that were completely unstable with documented displacement into both flexion and extension as seen on fluoroscopic examination with the patient under anesthesia. We used a new technique for closed reduction and fixation of these fractures, and then we assessed fracture-healing and complications from the injury and treatment. RESULTS: All nine fractures were treated satisfactorily with closed reduction and percutaneous pinning. The complication rate associated with these unstable fractures was no higher than that associated with the 288 more stable fractures. Seven of the nine fractures were stabilized with lateral entry pin placement, and two fractures were stabilized with crossed medial and lateral pins. None of the patients had a nonunion, cubitus varus, malunion, additional surgery, or loss of motion. CONCLUSIONS: In rare supracondylar fractures in children, multidirectional instability results in displacement into flexion and/or extension. This fracture can be classified as type IV according to the Gartland system, as it is less stable than a Gartland type-III extension supracondylar fracture. These fractures can be treated successfully with a new technique of closed reduction and percutaneous pinning, thus avoiding open reduction.

Bilateral total knee arthroplasty--staged or simultaneous? Ontario's orthopedic surgeons reply.

BACKGROUND: Total knee replacement is now the most common joint replacement procedure performed in Ontario, and many patients require bilateral replacement. However, whether bilateral total knee arthroplasty (TKA) should be staged or simultaneous is hotly debated. To determine the current common operative practices of orthopedic surgeons in Ontario, we carried out a province-wide survey. METHODS: Orthopedic surgeons from Ontario listed in the 1999 Canadian Medical Directory or the membership list of the Canadian Orthopaedic Association were sent questionnaires, asking about their practice in the timing of bilateral TKA, tourniquet use, type of guide and use of techniques to minimize fat embolization. RESULTS: Of the 416 surveys mailed, 219 (53%) surgeons responded. The majority responded that they perform staged bilateral TKA (28% 3-mo interval and 37% 6-mo interval). Simultaneous TKA with 2 teams was the least performed procedure (2%). When performing bilateral TKA, 95% of surgeons use an intramedullary femoral alignment guide, 78% utilize an over-reamed entry hole and 53% suction the canal before inserting the guide rod. With respect to the tibia, 32% use an intramedullary guide, 60% over-ream the entry hole and 60% suction the entry hole; 22% of surgeons stated that they had never considered over-reaming or suctioning the canal to minimize fat embolization. CONCLUSIONS: There is no consensus regarding the timing of bilateral TKA in Ontario. Furthermore, many surgeons are not overdrilling or suctioning the femoral canal despite evidence in the literature that overdrilling may be beneficial in decreasing fat embolization. Further research is required to compare the risk of complications of bilateral TKA after staged versus simultaneous TKA.

Comparison of two methods of reconstruction for primary malignant tumors at the knee: a sequential cohort study.

BACKGROUND AND OBJECTIVES: The purpose of this study was to compare the complications and functional outcome associated with the use of an irradiated allograft-implant composite or a bone-ingrowth modular tumor prosthesis for replacement of the knee joint after resection of a bone sarcoma from the distal femur or proximal tibia. METHODS: Eleven patients initially received an allograft reconstruction, followed by 64 treated with a tumor prosthesis. The primary analysis concerned reconstructive failure, defined by the requirement for removal of the original construct. Functional outcome was assessed by using the 1987 Musculoskeletal Tumor Society rating system. RESULTS: Reconstructive failure occurred in 6 of 11 (55%) allograft constructs compared with 10 of 64 (16%) tumor prostheses (P = 0.009). Failures were due to infection (2 of 11 allografts versus 4 of 64 prostheses; P = 0.2) or mechanical complications (4 of 11 allograft fractures versus 5 of 64 broken prosthetic stems and 1 aseptically loose prosthesis; P = 0.03). The limb salvage rate was 95% (61 of 64) for patients with a tumor prosthesis compared with 64% (7 of 11) for those with an allograft (P = 0.007). Patients with a tumor prosthesis had a better functional outcome with a mean score of 75% compared with 57% for those with an allograft reconstruction (P = 0.006). CONCLUSIONS: This comparative study suggests that limb salvage surgery at the knee has a better and more predictable outcome with a tumor prosthesis than with an allograft-implant reconstruction.

Surgeon compensation and motivation.

HYPOTHESIS: Financial incentives are the only form of compensation that will motivate surgeons at an academic health sciences center to perform the tasks outlined in the hospital's mission statement. DESIGN: A questionnaire divided into 5 sections: demographics, compensation, time allocation, benefits and incentives, and motivational factors. SETTING: The Department of Surgery, The Toronto Hospital, Toronto, Ontario. PARTICIPANTS: All academic surgeons (N=64) practicing at The Toronto Hospital in July 1997. RESULTS: Of the 64 eligible mailed surveys, there were responses for 59. Of these 59 surgeons, 48 (81%) receive compensation through a fee-for-service method. However, only 32 (54%) of the surgeons prefer the fee-for-service method, while 18 (31%) prefer salary and 9 (15%) prefer an alternative system. On average, these academic surgeons spend 44% of their time teaching or performing research, for which they receive 14% of their total income. Of the motivational factors assessed, financial bonuses are a positive motivational factor for all "surgeon tasks." In addition, task-specific motivational factors were established for research, teaching, and operating, including research facilities, mentorship and prestige, and interesting case types, respectively. CONCLUSIONS: Surgeons are not appropriately renumerated for time spent on academic activities, and many would prefer an alternative form of compensation to the fee-for-service method. Knowledge that surgeons are receptive to tasks supporting the hospital's mission statement leads us to conclude that appropriate motivation can shape the activity of academic surgeons. Financial rewards ranked the highest as a motivational factor for all surgeon tasks; however, task-specific motivational factors were identified. Overall, multiple factors, specifically targeted to the individual, will serve to motivate. Thus, compensation packages based on individual preferences and personal motivational factors will be the most successful.

A survey of in vivo benzo[alpha]pyrene metabolism in small benthic marine invertebrates.

A micro-extraction technique was used to examine in vivo polycyclic aromatic hydrocarbon (PAH) metabolism in 10 small invertebrate species exposed to sediments amended with 3H-benzo[alpha]pyrene (BaP). Phyla examined included Mollusca (Hydrobia totteni, Ilyanassa obsoleta, Yoldia limatula, and Gemma gemma), Annelida (Nereis succinea, Pectinaria gouldii, Haploscolopolous sp., and Capitella sp. 1) and Arthropoda (Edotea triloba, and Gammarus mucronatus). Organisms were exposed to BaP-labeled sediments, harvested, and parent BaP separated from all polar metabolites by liquid extraction The percent of BaP-derived radio-activity present as polar metabolites ranged from 96% for N. succinea to 7% for P. gouldii. Wide ranges in metabolic capability were also observed between species in the other two phyla examined. Reverse-phase HPLC analysis of extracts of representative species from each phyla indicated that all these organisms form bay region metabolites, with two species forming the 7,8-dihydrodiol (N. succinea and G. mucronatus). In light of the high variability in metabolic capability observed within each phylum, species-specific information on metabolic ability should be obtained before assessing bioaccumulation, critical body burdens, or trophic transfer of PAHs in invertebrates.

The treatment of supracondylar fractures in children with an absent radial pulse.

The purpose of this study was to determine the outcome of patients with a supracondylar fracture and an absent radial pulse. All children with displaced extension-type supracondylar fractures from 1984-1992 were eligible. Of 326 children with supracondylar fractures, 22 had an absent radial pulse on admission. Fifteen of the 22 children had a well-perfused hand after closed reduction and K-wire fixation. Five had no pulse but a well-perfused hand after reduction and immobilization of the elbow in slight flexion; none had any problem at final review. Seven patients who had a cold white hand after closed reduction received open reduction of fracture and arterial exploration. In conclusion, the initial treatment for children with displaced supracondylar fractures with an absent radial pulse should be closed reduction, K-wire fixation, and immobilization in < 90 degrees of flexion. Children who have a well-perfused hand but an absent radial pulse after satisfactory closed reduction do not necessarily require routine exploration of the brachial artery.

Proximal femoral allografts for reconstruction of bone stock in revision arthroplasty of the hip.

Proximal femoral allografts have been used to restore uncontained circumferential defects of the multiply revised total hip arthroplasty. These grafts are used with long stem components that are cemented to the graft but not the host. The junction of host and graft is stabilized by the stem and a step cut with cerclage wires. Autograft bone is placed at the junctions to induce union. Full weightbearing is delayed until union occurs between the graft and the host femur, usually by 3 months. One hundred sixty-eight structural femoral allografts were done; average followup was 4.8 years as of January 1, 1995. Success was defined as an increase in the clinical score of at least 20 points, a stable implant, and no need for further surgery related to the allograft. The success rate in 130 patients with at least 2 years followup is 85%. There have been 17 revisions in 16 patients: 3 revisions for infection, 8 for dislocation, 5 for nonunion, and 1 for pain. The revision rate is 10.1%. Radiographic analysis showed 7 nonunions, minor resorption in 6 patients, and significant resorption in 1 patient. All implants are stable with no lucent lines. The results support using this technique for full circumferential segmental proximal femoral defects in revision hip arthroplasty.

A preliminary trial of the gel test for blood group serology.

The gel test, first reported in 1988, can be used for most areas of blood group serology, but this report deals specifically with ABO/Rh typing and antibody screening and investigation. The technique is simple and quick to perform and the reading of results is standardised and clean with no false-positive reactions being found in antiglobulin tests. Since gel anti-human globulin tests require no washing and the test cards may be sealed during centrifugation, the system is particularly advantageous for 'loosely bound' antibodies and 'high-risk' samples.

Domestic accidents: their cause and prevention.

The study of domestic accidents, which includes accidents in and around the home and in institutions, is of increasing importance. The mortality statistics are shown in Table 1. In 1974, 18,335 people died from accidents in the UK (RoSPA, 1974) equivalent to the population of a reasonably sized town. Accidents form one of the four main causes of death in this country and have become relatively more common in recent years. Analysis of the causes of home accidents make it possible to plan ways of preventing them. General practitioners and their colleagues in the primary health care team have the principal responsibility.