Descriptive Epidemiology of Upper Extremity Septic Arthritis in Children-Review of a Retrospective Multicenter Database

BACKGROUND

There is limited information on the presentation and management of upper extremity septic arthritis (UESA) in children. Our purpose was to report on the characteristics and short-term treatment outcomes of pediatric UESA from a multicenter database.

METHODS

Patients with UESA were identified from a multicenter retrospective musculoskeletal infection database. Demographics, laboratory tests, culture results, number of surgeries, and complications were collected.

RESULTS

Of 684 patients with septic arthritis (SA), 68 (10%) patients had UESA. Septic arthritis was most common in the elbow (53%), followed by the shoulder (41%) and wrist (4%). The median age at admission was 1.7 years [interquartile range(IQR, 0.8-8.0 y)] and 66% of the cohort was male. Blood cultures were collected in 65 (96%) patients with 23 (34%) positive results. Joint aspirate and/or tissue cultures were obtained in 66 (97%) patients with 49 (72%) positive results. Methicillin-sensitive Staphylococcus aureus (MSSA) was the most common causative organism overall, but Streptococcus was the most common pathogen in the shoulder. Sixty-six (97%) patients underwent irrigation and debridement, with 5 (7%) patients requiring 2 surgeries and 1 patient (1%) requiring 3 surgeries. The median length of stay was 4.9 days (IQR, 4.0-6.3 d). Thirty-one (46%) children had adjacent musculoskeletal infections and/or persistent bacteremia. No patients experienced venous thromboembolism, and 4 patients with associated osteomyelitis experienced a musculoskeletal complication (3 avascular necrosis, 1 pathologic fracture). One child had re-admission and 3 children with associated osteomyelitis had a recurrence of UESA. Comparison between elbow and shoulder locations showed that children with septic arthritis of the shoulder were younger (4.6 vs. 1.0 y, P =0.001), and there was a difference in minimum platelet count (280 vs. 358 ×10 9 cells/L, P =0.02).

CONCLUSIONS

UESA comprises 10% of cases of septic arthritis in children. The elbow is the most common location. Shoulder septic arthritis affects younger children. MSSA is the most common causative organism in UESA, but Streptococcus is common in shoulder septic arthritis. Irrigation and debridement result in excellent short-term outcomes with a low complication rate. Re-admissions and repeat surgical interventions are rare.

LEVEL OF EVIDENCE

Level IV, prognostic.

Interobserver and Intraobserver Agreement are Unsatisfactory When Determining Abstract Study Design and Level of Evidence

BACKGROUND

Understanding differences between types of study design (SD) and level of evidence (LOE) are important when selecting research for presentation or publication and determining its potential clinical impact. The purpose of this study was to evaluate interobserver and intraobserver reliability when assigning LOE and SD as well as quantify the impact of a commonly used reference aid on these assessments.

METHODS

Thirty-six accepted abstracts from the Pediatric Orthopaedic Society of North America (POSNA) 2021 annual meeting were selected for this study. Thirteen reviewers from the POSNA Evidence-Based Practice Committee were asked to determine LOE and SD for each abstract, first without any assistance or resources. Four weeks later, abstracts were reviewed again with the guidance of the Journal of Bone and Joint Surgery (JBJS) LOE chart, which is adapted from the Oxford Centre for Evidence-Based Medicine. Interobserver and intraobserver reliability were calculated using Fleiss' kappa statistic (k). χ2 analysis was used to compare the rate of SD-LOE mismatch between the first and second round of reviews.

RESULTS

Interobserver reliability for LOE improved slightly from fair (k=0.28) to moderate (k=0.43) with use of the JBJS chart. There was better agreement with increasing LOE, with the most frequent disagreement between levels 3 and 4. Interobserver reliability for SD was fair for both rounds 1 (k=0.29) and 2 (k=0.37). Similar to LOE, there was better agreement with stronger SD. Intraobserver reliability was widely variable for both LOE and SD (k=0.10 to 0.92 for both). When matching a selected SD to its associated LOE, the overall rate of correct concordance was 82% in round 1 and 92% in round 2 (P<0.001).

CONCLUSION

Interobserver reliability for LOE and SD was fair to moderate at best, even among experienced reviewers. Use of the JBJS/Oxford chart mildly improved agreement on LOE and resulted in less SD-LOE mismatch, but did not affect agreement on SD.

LEVEL OF EVIDENCE

Level II.

Late Presentation of Developmental Hip Dislocation: A Case Report

CASE

We describe a patient who was diagnosed with developmental hip dislocation at 21 months of age despite having had normal ultrasonography findings at 5 weeks of age.

CONCLUSION

This case report provides evidence that late developmental hip dislocation can occur despite normal clinical and sonographic findings early in life, and that it is difficult to know the cause of developmental hip dislocation when it presents late.

Pediatric Type II Tibial Spine Fractures: Addressing the Treatment Controversy With a Mixed-Effects Model

Background:

Tibial spine fractures, although relatively rare, account for a substantial proportion of pediatric knee injuries with effusions and can have significant complications. Meyers and McKeever type II fractures are displaced anteriorly with an intact posterior hinge. Whether this subtype of pediatric tibial spine fracture should be treated operatively or nonoperatively remains controversial. Surgical delay is associated with an increased risk of arthrofibrosis; thus, prompt treatment decision making is imperative.

Purpose:

To assess for variability among pediatric orthopaedic surgeons when treating pediatric type II tibial spine fractures.

Study Design:

Cross-sectional study.

Methods:

A discrete choice experiment was conducted to determine the patient and injury attributes that influence the management choice. A convenience sample of 20 pediatric orthopaedic surgeons reviewed 40 case vignettes, including physis-blinded radiographs displaying displaced fractures and a description of the patient’s sex, age, mechanism of injury, and predominant sport. Surgeons were asked whether they would treat the fracture operatively or nonoperatively. A mixed-effects model was then used to determine the patient attributes most likely to influence the surgeon’s decision, as well as surgeon training background, years in practice, and risk-taking behavior.

Results:

The majority of respondents selected operative treatment for 85% of the presented cases. The degree of fracture displacement was the only attribute significantly associated with treatment choice (P < .001). Surgeons were 28% more likely to treat the fracture operatively with each additional millimeter of displacement of fracture fragment. Over 64% of surgeons chose to treat operatively when the fracture fragment was displaced by ≥3.5 mm. Significant variation in surgeon’s propensity for operative treatment of this fracture was observed (P = .01). Surgeon training, years in practice, and risk-taking scores were not associated with the respondent’s preference for surgical treatment.

Conclusion:

There was substantial variation among pediatric orthopaedic surgeons when treating type II tibial spine fractures. The decision to operate was based on the degree of fracture displacement. Identifying current treatment preferences among surgeons given different patient factors can highlight current variation in practice patterns and direct efforts toward promoting the most optimal treatment strategies for controversial type II tibial spine fractures.

Vitamin D Insufficiency and Fracture Risk in Urban Children

BACKGROUND

Investigation into the role of vitamin D in fractures in the pediatric population has been limited despite estimates that as many as 70% of American children have inadequate vitamin D levels (measured as 25-hydroxyvitamin D, 25(OH)D). The purpose of this study was to evaluate vitamin D's role in pediatric fracture risk by comparing 25(OH)D between fractured and nonfractured cohorts.

METHODS

A 12-month prospective case-control study was completed in children aged 2 to 14 years in an urban, academic hospital. Sixty fractured children requiring conscious sedation or general anesthesia for management were compared with 60 nonfractured controls. All participants and their guardians were surveyed for low bone density risk factors, and total serum 25(OH)D was measured. Statistical analysis was completed using Student t tests, χ tests, analysis of variance, and logistic regression models.

RESULTS

After controlling for age and daily sun exposure, lower total serum 25(OH)D was associated with higher fracture risk (odds ratio=0.94; 95% confidence interval, 0.90-0.99; P=0.023). In the fractured cohort, 6 (10%) patients were deficient (25(OH)D<20 ng/mL) and 33 (55%) were insufficient (25(OH)D, 20 to 30 ng/mL). Of the nonfractured population, 8 (13%) were deficient and 19 (32%) were insufficient. There were more insufficient patients in the fractured than in the nonfractured cohort (odds ratio=2.99; 95% confidence interval, 1.27-7.0; P=0.037).

CONCLUSIONS

Higher fracture incidence is associated with serum 25(OH)D insufficiency. Hypovitaminosis D may place the pediatric population at increased risk for fracture. Consideration should be given to routine assessment of vitamin D in fractured children.

LEVEL OF EVIDENCE

Prognostic level III-prospective case-control study.

Radiofrequency ablation in the treatment of osteoid osteoma: results and complications

BACKGROUND

Percutaneous radiofrequency ablation (RFA) for treatment of osteoid osteoma is effective and avoids the potential complications of open surgical resection. This study evaluates the efficacy of RFA at a single tertiary-care pediatric hospital and highlights an important complication.

MATERIALS AND METHODS

The medical records of 21 cases of RFA in 21 children between 2004 and 2010 were reviewed retrospectively for demographic data, lesion site, access point and technique for ablation, clinical outcome and complications.

RESULTS

Clinical follow-up was available for 17/21 children (81%) at an average of 17.0 months (range 0.5-86.1 months). No persistence or recurrence of pre-procedural pain was noted. Two children (9.5%) had a complication, including a burn to the local skin and muscle requiring local wound care, and a late subtrochanteric femur fracture treated successfully with open reduction internal fixation.

CONCLUSION

RFA is a safe and effective alternative to surgical resection of the osteoid osteoma nidus. When accessing the proximal femur, the risk of late post-procedural fracture must be considered and discussed with the family. An understanding of biomechanical principles in the proximal femur might provide an effective strategy for limiting this risk.

Femoral fractures in adolescents: a comparison of four methods of fixation

BACKGROUND

The optimal management of femoral fractures in adolescents is controversial. This study was performed to compare the results and complications of four methods of fixation and to determine the factors related to those complications.

METHODS

We conducted a retrospective cohort study of 194 diaphyseal femoral fractures in 189 children and adolescents treated with elastic stable intramedullary nail fixation, external fixation, rigid intramedullary nail fixation, or plate fixation. After adjustment for age, weight, energy of the injury, polytrauma, fracture level and pattern, and extent of comminution, treatment outcomes were compared in terms of the length of the hospital stay, time to union, and complication rates, including loss of reduction requiring a reoperation, malunion, nonunion, refracture, infection, and the need for a reoperation other than routine hardware removal.

RESULTS

The mean age of the patients was 13.2 years, and their mean weight was 49.5 kg. There was a loss of reduction of two of 105 fractures treated with elastic nail fixation and ten of thirty-three treated with external fixation (p < 0.001). At the time of final follow-up, five patients (two treated with external fixation and one in each of the other groups) had >or=2.0 cm of shortening. Eight of the 104 patients (105 fractures) treated with elastic nail fixation underwent a reoperation (two each because of loss of reduction, refracture, the need for trimming or advancement of the nail, and delayed union or nonunion). Sixteen patients treated with external fixation required a reoperation (ten because of loss of reduction, one for replacement of a pin complicated by infection, one for débridement of the site of a deep infection, three because of refracture, and one for lengthening). One patient treated with a rigid intramedullary nail required débridement at the site of a deep infection, and one underwent removal of a prominent distal interlocking screw. One fracture treated with plate fixation required refixation following refractures. A multivariate analysis with adjustment for baseline differences showed external fixation to be associated with a 12.41-times (95% confidence interval = 2.26 to 68.31) greater risk of loss of reduction and/or malunion than elastic stable intramedullary nail fixation.

CONCLUSIONS

External fixation was associated with the highest rate of complications in our series of adolescents treated for a femoral fracture. Although the other three methods yielded comparable outcomes, we cannot currently recommend one method of fixation for all adolescents with a femoral fracture. The choice of fixation will remain influenced by surgeon preference based on expertise and experience, patient and fracture characteristics, and patient and family preferences.

Comparison of surgeon and physiotherapist-directed Ponseti treatment of idiopathic clubfoot

BACKGROUND

Increasingly, the Ponseti method has been adopted worldwide as the preferred method of managing idiopathic clubfoot deformity. Following the successful implementation of the Ponseti method by orthopaedic surgeons in our institution, a clubfoot clinic was established in 2003. This clinic is directed by a physiotherapist who, using the Ponseti protocol, performs the serial cast treatment and supervises the brace management of all children with idiopathic clubfoot deformity. The purpose of this study was to compare the outcomes of physiotherapist-directed with surgeon-directed Ponseti cast treatment of idiopathic clubfeet.

METHODS

We performed a retrospective cohort study of all patients with idiopathic clubfoot deformity treated from 2002 to 2006 and followed for a minimum of two years. Twenty-five children (thirty-four clubfeet) treated by surgeons were compared with ninety-five children (137 clubfeet) treated by a physiotherapist. The outcomes that were evaluated included the number of casts required, the rate of percutaneous Achilles tenotomy, the rate of recurrence, the failure rate, and the need for additional surgical procedures.

RESULTS

At the time of presentation, the patients in the two groups were similar in terms of age, sex distribution, laterality of the clubfoot, and history of treatment. The mean duration of follow-up was thirty-four months in the physiotherapist-directed group and forty-eight months in the surgeon-directed group. No significant difference was found between the two groups with regard to the mean number of initial casts, the Achilles tenotomy rate, or the failure rate. Recurrence requiring additional treatment occurred in 14% of the feet in the physiotherapist-directed group and in 26% of the feet in the surgeon-directed group (p = 0.075). Additional procedures, including repeat Achilles tenotomy or a limited posterior or posteromedial release, were required in 6% of the feet in the physiotherapist-directed group and in 18% of those in the surgeon-directed group (p = 0.025).

CONCLUSIONS

In our institution, the Ponseti method of cast treatment of idiopathic clubfeet was as effective when it was directed by a physiotherapist as it was when it was directed by a surgeon, with fewer recurrences and a less frequent need for additional procedures in the physiotherapist-directed group. The introduction of the physiotherapist-supervised clubfoot clinic at our institution has been effective without compromising the quality of care of children with clubfoot deformity.

Scoliosis: Review of diagnosis and treatment

Scoliosis is a spinal deformity consisting of lateral curvature and rotation of the vertebrae. The causes of scoliosis vary and are classified broadly as congenital, neuromuscular, syndrome-related, idiopathic and spinal curvature due to secondary reasons. The majority of scoliosis cases encountered by the general practitioner will be idiopathic. The natural history relates to the etiology and age at presentation, and usually dictates the treatment. However, it is the patient's history, physical examination and radiographs that are critical in the initial evaluation of scoliosis, and in determining which patients need additional considerations. Scoliosis with a primary diagnosis (nonidiopathic) must be recognized by the physician to identify the causes, which may require intervention. Patients with congenital scoliosis must be evaluated for cardiac and renal abnormalities. School screening for scoliosis is controversial and is falling out of favour. The treatment for idiopathic scoliosis is based on age, curve magnitude and risk of progression, and includes observation, orthotic management and surgical correction with fusion. A child should be referred to a specialist if the curve is greater than 10 degrees in a patient younger than 10 years of age, is greater than 20 degrees in a patient 10 years of age or older, has atypical features or is associated with back pain or neurological abnormalities.

A comparison of the thoracolumbosacral orthoses and providence orthosis in the treatment of adolescent idiopathic scoliosis: results using the new SRS inclusion and assessment criteria for bracing studies

This is a retrospective cohort study comparing the effectiveness of the thoracolumbosacral orthosis (TLSO) and the Providence orthosis in the treatment of adolescent idiopathic scoliosis (AIS) using the new Scoliosis Research Society (SRS) Committee on Bracing and Nonoperative Management inclusion and assessment criteria for bracing studies. These new criteria will make future studies comparable and more valid and accurate.

METHODS

We have used a custom TLSO (duration, 22 hours/day) and the Providence orthosis (duration, 8-10 hours/night) to control progressive AIS curves. Only 83 of 160 patients met the new SRS inclusion criteria: age of 10 years and older at initiation of bracing; initial curve of 25 to 40 degrees; Risser sign 0 to 2; female; premenarcheal or less than 1 year past menarche; and no previous treatment. There were 48 patients in the TLSO group and 35 in the Providence group. The new SRS assessment criteria of effectiveness included the percentage of patients who had 5 degrees or less and 6 degrees or more of curve progression at maturity, the percentage of patients whose curve progressed beyond 45 degrees, the percentage of patients who had surgery recommended or undertaken, and a minimum of 2 years of follow-up beyond maturity in those patients who were thought to have been successfully treated. All patients are evaluated regardless of compliance (intent to treat).

RESULTS

There were no significant differences in age at brace initiation, initial primary curve magnitude, sex, or initial Risser sign between the 2 groups. In the TLSO group, only 7 patients (15%) did not progress (<or=5 degrees), whereas 41 patients (85%) progressed by 6 degrees or more, including the 30 patients whose curves exceeded 45 degrees. Thirty-eight patients (79%) required surgery. In the Providence group, 11 patients (31%) did not progress, whereas 24 patients (69%) progressed by 6 degrees or more, including 15 patients whose curves exceeded 45 degrees. Twenty-one patients (60%) required surgery. However, when the initial curve at initiation of bracing was 25 to 35 degrees, the results improved. Five (15%) of 34 patients in the TLSO group and 10 (42%) of 24 patients in the Providence group did not progress, whereas 29 patients (85%) and 14 patients (58%), respectively, progressed by 6 degrees or more, and 26 patients (76%) and 11 patients (46%), respectively, required surgery.

CONCLUSIONS

Using the new SRS bracing criteria, the Providence orthosis was more effective for avoiding surgery and preventing curve progression when the primary initial curves at bracing was 35 degrees or less. However, the overall success of orthotic management for AIS in both groups was inferior to previous studies. Our results raise the question of the effectiveness of orthotic management in AIS and support the need for a multicenter, randomized study using these new criteria.

Augmentation of spinal arthrodesis with autologous bone marrow in a rabbit posterolateral spine fusion model

STUDY DESIGN

Posterolateral spinal fusion with autologous bone marrow aspirate in addition to autograft iliac crest bone graft in a rabbit model.

OBJECTIVE

To demonstrate that the addition of autologous bone marrow can have positive effects on bone formation and spinal fusion.

SUMMARY OF BACKGROUND DATA

Bone marrow has been shown to contain osteoprogenitor cells. A number of studies have demonstrated that bone formation is possible with autologous marrow injection into orthotopic sites such as that performed in femur fracture models.

METHODS

A bone paucity model of posterolateral spine fusion was developed. The control animals received 0.8 g of morselized autogenous iliac crest bone graft harvested from a single iliac crest. The graft was mixed with 2 mL of clotted peripheral blood. In the experimental group, 2 mL of bone marrow aspirated from the opposite iliac crest was substituted for the peripheral blood clot. All rabbits were killed at 12 weeks, and the specimens were subjected to evaluation by posteroanterior radiography for the presence of fusion, computed tomography for bone volume, and biomechanical testing for stiffness.

RESULTS

Successful fusion was achieved in 61% of the animals in the experimental group versus 25% in the control group (P < 0.05). The fusion mass in the experimental group had a mean volume of 919 +/- 387 mm3 versus 667 +/- 512 mm3 for the control group, as measured from computed tomography images. The results of the biomechanical testing validated the radiographic scoring system. The stiffness in specimens, graded as having a radiographic score of 4, was significantly greater than in specimens with radiographic scores of 1 and 2.

CONCLUSION

In cases for which an adequate quantity of autogenous bone graft is not available, addition of bone marrow may facilitate greater bone formation and successful fusion.