M. Timothy Hresko

Lateral entry compared with medial and lateral entry pin fixation for completely displaced supracondylar humeral fractures in children. A randomized clinical trial.

BACKGROUND Closed reduction and percutaneous pin fixation is the treatment of choice for completely displaced (type-III) extension supracondylar fractures of the humerus in children, although controversy persists regarding the optimal pin-fixation technique. The purpose of this study was to compare the efficacy of lateral entry pin fixation with that of medial and lateral entry pin fixation for the operative treatment of completely displaced extension supracondylar fractures of the humerus in children. METHODS This prospective, randomized clinical trial had sufficient power to detect a 10% difference in the rate of loss of reduction between the two groups. The techniques of lateral entry and medial and lateral entry pin fixation were standardized in terms of the pin location, the pin size, the incision and position of the elbow used for medial pin placement, and the postoperative course. The primary study end points were a major loss of reduction and iatrogenic ulnar nerve injury. Secondary study end points included radiographic measurements, clinical alignment, Flynn grade, elbow range of motion, function, and complications. RESULTS The lateral entry group (twenty-eight patients) and the medial and lateral entry group (twenty-four patients) were similar in terms of mean age, sex distribution, and preoperative displacement, comminution, and associated neurovascular status. No patient in either group had a major loss of reduction. There was no significant difference between the rates of mild loss of reduction, which occurred in six of the twenty-eight patients treated with lateral entry and one of the twenty-four treated with medial and lateral entry (p = 0.107). There were no cases of iatrogenic ulnar nerve injury in either group. There were also no significant differences (p > 0.05) between groups with respect to the Baumann angle, change in the Baumann angle, humerocapitellar angle, change in the humerocapitellar angle, Flynn grade, carrying angle, elbow flexion, elbow extension, total elbow range of motion, return to function, or complications. CONCLUSIONS With use of the specific techniques employed in this study, both lateral entry pin fixation and medial and lateral entry pin fixation are effective in the treatment of completely displaced (type-III) extension supracondylar fractures of the humerus in children. LEVEL OF EVIDENCE Therapeutic Level I. See Instructions to Authors for a complete description of levels of evidence.

Tibial Eminence Fractures in Children: Prevalence of Meniscal Entrapment:

Background Meniscal entrapment under a displaced tibial eminence fragment may be a rationale for arthroscopic or open reduction in type 2 and 3 tibial eminence fractures. Purpose To determine the prevalence of meniscal entrapment in children with type 2 and 3 tibial eminence fractures. Study Design Case series. Methods Records of a consecutive series of 80 skeletally immature patients (mean age, 11.6 years; range, 5 to 16) who underwent arthroscopic (71), open (5), or combined arthroscopic and open (4) reduction and internal fixation of type 3 tibial eminence fractures (57) or type 2 fractures that did not reduce in extension (23) from 1993 to 2001 were reviewed. Results Entrapment of the anterior horn of the medial meniscus (36), intermeniscal ligament (6), or anterior horn of the lateral meniscus (1) was seen in 26% (6 of 23) of type 2 fractures and 65% (37 of 57) of type 3 fractures. An associated meniscal tear was seen in 3.8% of patients (3 of 80). Conclusions Meniscal entrapment is common in patients with type 2 and 3 tibial eminence fractures. Arthroscopic or open reduction should be considered for type 3 fractures and for type 2 fractures that do not reduce in extension to remove the incarcerated meniscus, allowing for anatomic reduction.

Osteonecrosis of the femoral head associated with slipped capital femoral epiphysis.

We performed a retrospective analysis of 212 patients (299 hips) with slipped capital femoral epiphysis (SCFE) over a 9-year period to assess the incidence of osteonecrosis of the femoral head. Risk factors for the occurrence of osteonecrosis and the influence of treatment on the development of osteonecrosis were determined. Osteonecrosis occurred in 4 hips with unstable SCFE (4/27) and did not occur in hips with stable SCFE (0/272). The proportion of hips in which osteonecrosis developed was significantly higher among the unstable hips (4/27 vs. 0/272, p < 0.0001). Among those with an unstable hip, younger age at presentation was a predictor of a poorer outcome. Magnitude of the slip, magnitude of reduction, and chronicity of the slip were not predictive of a poorer outcome in the unstable group. In situ fixation of the minimally or moderately displaced “unstable” SCFE demonstrated a favorable outcome. We have identified the hip at risk as an unstable SCFE. The classification of hips as unstable if the epiphysis is displaced from the metaphysis or if the patient is unable to walk is most useful in predicting a hip at risk for osteonecrosis.

Discoid lateral meniscus: prevalence of peripheral rim instability.

The purpose of this study was to determine the prevalence of peripheral rim instability in discoid lateral meniscus. A consecutive series of 112 patients (128 knees) (mean age 10.0 years [range 1 month to 22 years]) who underwent arthroscopic evaluation and treatment of a discoid lateral meniscus between 1993 and 2001 was reviewed. Of those discoid menisci classified intraoperatively (n = 87), 62.1% (n = 54) were complete discoid lateral menisci and 37.9% (n = 33) were incomplete discoid lateral menisci. An associated meniscal tear was present in 69.5% (n = 89) of all knees studied. Overall, 28.1% (n = 36) of discoid lateral menisci had peripheral rim instability: 47.2% (n = 17) were unstable at the anterior-third peripheral attachment, 11.1% (n = 4) at the middle-third peripheral attachment, and 38.9% (n = 14) at the posterior-third peripheral attachment. Thirty-one of the 36 unstable discoid menisci underwent repair of the peripheral meniscal rim attachment. One patient underwent a complete, open meniscectomy. Peripheral rim instability was significantly more common in complete discoid lateral menisci (38.9% vs. 18.2%; P = 0.043) and in younger patients (8.2 vs. 10.7 years; P = 0.002). The frequency of peripheral instability mandates a thorough assessment of meniscal stability at all peripheral attachments during the arthroscopic evaluation and treatment of discoid lateral meniscus, particularly in complete variants and in younger children.

Prophylactic Pinning of the Contralateral Hip After Unilateral Slipped Capital Femoral Epiphysis

BACKGROUND The management of the contralateral hip after unilateral slipped capital femoral epiphysis is controversial. The purpose of this study was to determine, with use of expected-value decision analysis, the optimal management strategy-prophylactic in situ pinning versus observation-for the contralateral hip. METHODS Outcome probabilities were determined from a systematic review of the literature. Utility values were obtained from a questionnaire on patient preferences completed with use of a visual analog scale by twenty-five adolescent male patients without slipped capital femoral epiphysis. A decision tree was constructed, fold-back analysis was performed to determine the optimal treatment, and one and two-way sensitivity analyses were performed to determine the effect on decision-making of varying outcome probabilities and utilities. RESULTS Observation was the optimal management strategy for the contralateral hip given the outcome probabilities and utilities that we studied (the expected value was 9.5 for observation and 9.2 for prophylactic in situ pinning, with a marginal value of 0.3). Increased rates of a late second slip favored prophylactic in situ pinning (the threshold probability was 27%). Risk-taking patients with a high utility for uncomplicated prophylactic in situ pinning favored prophylaxis (the threshold utility was 9.8). CONCLUSIONS The iatrogenic risks of treating a healthy patient or an uninvolved body part rarely outweigh the potential benefits unless the probability of the adverse event is likely and the consequences of the adverse event are very severe. In this decision analysis, the optimal decision was observation. In cases where the probability of contralateral slipped capital femoral epiphysis exceeds 27% or in cases where reliable follow-up is not feasible, pinning of the contralateral hip is favored. For a given individual patient, the optimal strategy depends not only on probabilities of the various outcomes but also on personal preference. Thus, we advocate a model of doctor-patient shared decision-making in which both the outcome probabilities and the patient preferences are considered in order to optimize the decision-making process. LEVEL OF EVIDENCE Economic and decision analysis, Level III-1 (limited alternatives and costs; poor estimates). See Instructions to Authors for a complete description of levels of evidence.

Pain Prevalence and Trajectories Following Pediatric Spinal Fusion Surgery

UNLABELLED Factors contributing to pain following surgery are poorly understood, with previous research largely focused on adults. With approximately 6 million children undergoing surgery each year, there is a need to study pediatric persistent postsurgical pain. The present study includes patients with adolescent idiopathic scoliosis undergoing spinal fusion surgery enrolled in a prospective, multicentered registry examining postsurgical outcomes. The Scoliosis Research Society Questionnaire-Version 30, which includes pain, activity, mental health, and self-image subscales, was administered to 190 patients prior to surgery and at 1 and 2 years postsurgery. A subset (n = 77) completed 5-year postsurgery data. Pain prevalence at each time point and longitudinal trajectories of pain outcomes derived from SAS PROC TRAJ were examined using analyses of variance and post hoc pairwise analyses across groups. Thirty-five percent of patients reported pain in the moderate to severe range presurgery. One year postoperation, 11% reported pain in this range, whereas 15% reported pain at 2 years postsurgery. At 5 years postsurgery, 15% of patients reported pain in the moderate to severe range. Among the 5 empirically derived pain trajectories, there were significant differences on self-image, mental health, and age. Identifying predictors of poor long-term outcomes in children with postsurgical pain may prevent the development of chronic pain into adulthood. PERSPECTIVE This investigation explores the prevalence of pediatric pain following surgery, up to 5 years after spinal fusion surgery. Five pain trajectories were identified and were distinguishable on presurgical characteristics of age, mental health, and self-image. This is the largest study to examine longitudinal pediatric pain trajectories after surgery.

Burst fractures of the fifth lumbar vertebra.

Eleven patients with burst fractures of the fifth lumbar vertebra were reviewed. The results of nonoperative treatment were compared with that of immediate surgery and stabilization with pedicle screw fixation. Five patients were treated nonoperatively and six patients underwent pedicle screw instrumentation and spinal fusion. Five patients had neurologic injury associated with their L5 burst fracture. Nonoperative treatment yielded excellent results in young patients with minimal canal compromise. Neurologic deficits responded more predictably to surgical decompression than to conservative treatment and internal fixation with pedicle screws restores spinal stability and allows early mobilization.

Serum Levels of Nickel and Chromium After Instrumented Posterior Spinal Arthrodesis

Study Design. Cross-sectional study of 37 patients to measure serum levels of nickel and chromium after posterior spinal arthrodesis using stainless steel implants. Objectives. To investigate the relationship between factors such as age, gender, pain, time from surgery, length of arthrodesis, and level of arthrodesis to serum metal ion levels after instrumented spinal arthrodesis. Summary of Background Data. Measurable levels of metal ions in the serum can be detected after the use of stainless steel implants. There is some evidence to suggest that long-term exposure can potentially be toxic. Posterior spinal arthrodesis with stainless steel implants is a common procedure to treat spinal deformity in the adolescent population; however, the extent of metal ion exposure after posterior spinal arthrodesis is unknown. Methods. Patients that underwent posterior instrumented spinal arthrodesis with more than 6 months follow-up were recruited for this study. Patients with altered neurologic function were excluded. Serum levels of nickel and chromium were measured using inductively coupled plasma mass spectrometry. Pain was assessed using the Oswestry questionnaire. Spine radiographs were used to look for evidence of pseudarthrosis. Forty-five patients were approached, and 37 agreed to the questionnaire and blood test. Ten patients were men and 27 were women. Mean age at surgery was 14 years with mean follow-up of 6 years. Statistical correlations between serum metal ion levels and age at surgery, time from surgery, gender, number of segments fused, spinal instrument interfaces, pain, and instrumentation type were assessed. Results. Abnormally high levels of nickel and chromium above normal levels (0.3 ng/mL for nickel, 0.15 ng/mL for chromium) could be detected in serum after posterior spinal arthrodesis using stainless steel implants. There was a significant inverse correlation between serum nickel (r = −0.61, P < 0.001) and chromium (r = −0.64, P < 0.001) levels and time from surgery. When patients were grouped based on lengths of time from surgery, 0 to 2 years (n = 7), 2 to 4 years (n = 11), and >4 years (n = 8), the mean ± SD for nickel (ng/mL) was 3.8 ± 2.6, 1.3 ± 1.1, and 0.9 ± 0.8, respectively. Analysis ofvariance revealed significant group differences (P =0.004). Similarly, the chromium levels were 2.7 ± 2.7, 0.6 ± 0.4, and 0.3 ± 0.3, respectively (P = 0.018). Only time from surgery was a significant multivariate predictor of nickel and chromium serum levels. Pseudarthrosis was not seen in this cohort. Conclusions. Elevated levels of nickel and chromium can be measured after posterior instrumented spinal arthrodesis. The levels diminish rapidly with time from surgery but still remained above normal levels 4 years after surgery. Long-term implication of this metal ion exposure is unknown and should be studied further.

Multiple level injuries in pediatric spinal trauma

BACKGROUND The incidence of concomitant, particularly noncontiguous, spine injuries in the pediatric population has not been well described. There is a balance between limiting radiation exposure and not missing concomitant injuries; understanding of this risk of concomitant spine injuries in this population is important. We hypothesize that the rate of concomitant spinal injuries in children is similar to adults. METHODS The trauma registry of a pediatric trauma center was queried for all patients who sustained spine injuries over a 10-year period. Patient demographics, presence of other injuries, treatment, location and nature of the spine injury, as well as presence of multiple level injuries were determined. RESULTS One hundred and ninety-five patients with spine injuries were noted. Patients over age 8 years accounted for 76% of spine injuries (148 of 195). Concomitant injuries to other levels in the spine occurred in 32% of the patients (62 of 195); 6% of these secondary injuries were noncontiguous and were at least three levels away from the primary injury. All of the concomitant injuries were either in the thoracic or in the upper lumbar spine. Neurovascular status and mechanism of injury were not different between patients sustaining concomitant injuries or not. CONCLUSIONS Pediatric spine injuries are more common in patients over age 8 years of age; these patients are more likely to have multiple levels of injury. Of patients sustaining a spine injury, 6% had noncontiguous second fractures, which is a rate similar to adults. Imaging studies evaluating patients with spinal injuries should include at least three levels above and below the primary level of injury as well as the entire thoracic spine and thoracolumbar junction.

Radiographic analysis of spondylolisthesis and sagittal spinopelvic deformity.

&NA; Traditional radiographic analysis of spondylolisthesis focuses on the regional sagittal deformity at the lumbosacral junction. Pelvic morphology has also been cited as an important factor that contributes to the development of high‐grade spondylolisthesis. However, the importance of global sagittal balance of the spine and pelvis in patients with spondylolisthesis has been emphasized recently. Patients with this condition can develop abnormal sagittal spinopelvic balance; restoration of sagittal spinal alignment can improve their health‐related quality of life. Reduction has been used to restore alignment, but its role in the management of highgrade spondylolisthesis is controversial. None of the current classification systems take sagittal sacropelvic and spinopelvic balance into account. Improved understanding of the relationship between the spine and pelvis has led to the development of a new classification system that incorporates analysis of spinopelvic balance in the radiographic assessment. This new system may aid surgeons in identifying patients who would benefit from a partial reduction procedure.