Relationship Between Age and Pathology With Treatment of Pediatric and Adolescent Discoid Lateral Meniscus: A Report From the SCORE Multicenter Database

BACKGROUND

Surgical treatment options of discoid lateral meniscus in pediatric patients consist of saucerization with or without meniscal repair, meniscocapular stabilization, and, less often, subtotal meniscectomy.

PURPOSE

To describe a large, prospectively collected multicenter cohort of discoid menisci undergoing surgical intervention, and further investigate corresponding treatment of discoid menisci.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A multicenter quality improvement registry (16 institutions, 26 surgeons), Sports Cohort Outcomes Registry, was queried. Patient characteristics, discoid type, presence and type of intrasubstance meniscal tear, peripheral rim instability, repair technique, and partial meniscectomy/debridement beyond saucerization were reviewed. Discoid meniscus characteristics were compared between age groups (<14 and >14 years old), based on receiver operating characteristic curve, and discoid morphology (complete and incomplete).

RESULTS

In total, 274 patients were identified (mean age, 12.4 years; range, 3-18 years), of whom 55.6% had complete discoid. Meniscal repairs were performed in 55.1% of patients. Overall, 48.5% of patients had rim instability and 36.8% had >1 location of peripheral rim instability. Of the patients, 21.5% underwent meniscal debridement beyond saucerization, with 8.4% undergoing a subtotal meniscectomy. Patients <14 years of age were more likely to have a complete discoid meniscus (P < .001), peripheral rim instability (P = .005), and longitudinal tears (P = .015) and require a meniscal repair (P < .001). Patients ≥14 years of age were more likely to have a radial/oblique tear (P = .015) and require additional debridement beyond the physiologic rim (P = .003). Overall, 70% of patients <14 years of age were found to have a complete discoid meniscus necessitating saucerization, and >50% in this young age group required peripheral stabilization/repair.

CONCLUSION

To preserve physiological "normal" meniscus, a repair may be indicated in >50% of patients <14 years of age but occurred in <50% of those >14 years. Additional resection beyond the physiological rim may be needed in 15% of younger patients and 30% of those aged >14 years.

Arthroscopic Treatment of Symptomatic Discoid Lateral Meniscus and Nondiscoid Meniscus in Adolescent Patients

BACKGROUND

Discoid lateral meniscus (DLM) is a rare condition. Patient-reported outcomes using validated instruments are underreported in the literature. DLM outcomes have not been directly compared with nondiscoid meniscus (non-DLM) in adolescent patients.

PURPOSE/HYPOTHESIS

This study sought to analyze the difference in patient characteristics, surgical treatment, and patient-reported outcomes for adolescent patients arthroscopically treated for symptomatic DLM and non-DLM pathology. We hypothesized that DLM and non-DLM patient-reported outcomes would be similar.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective review of patients aged <18 years with symptomatic DLM and non-DLM pathology was completed between 2015 and 2021 at a single academic institution. Chart reviews for patient characteristics and surgical operative indications and technique were completed. Patient-reported outcome scores were prospectively collected preoperatively and at 6 months, 1 year, and 2 years after surgery.

RESULTS

Patients in the DLM group (n = 48), when compared with the non-DLM group (n = 45), were younger (12.71 vs 15.78 years, respectively; P < .001) and had lower body mass index (24.53 vs 28.91, respectively; P < .02). Both groups were majority Hispanic and more commonly male (DLM 65% vs non-DLM 60%). All of the DLM patients had surgery on the lateral discoid meniscus (n = 48), whereas the non-DLM group had surgery on the lateral meniscus (n = 37), medial meniscus (n = 7), or both (n = 1). A majority of patients in both groups underwent meniscal repair (DLM 73% and non-DLM 62%), and there was no difference in surgical treatment between groups (P > .05). A statistically significant improvement was seen in International Knee Documentation Committee (IKDC) and Physical Activity Questionnaire (PAQ) scores from the preoperative assessment to 6 months, 1 year, and 2 years after surgery for both DLM and non-DLM groups (P < .05). No difference was found in scores between DLM and non-DLM groups, between sexes, or between age groups (<13 years or ≥13 years) (P > .05).

CONCLUSION

Although patients with DLM were younger and had lower body mass index, the IKDC and PAQ scores were not significantly different between the DLM and non-DLM groups. Both groups showed a significant improvement in scores relative to their preoperative scores. Sex and age did not affect IKDC or PAQ scores.

Increasing loads and diminishing returns: a biomechanical study of direct vertebral rotation

STUDY DESIGN

Biomechanical simulation of DVR and pure-moment testing on thoracic spines.

OBJECTIVES

Characterize load-deformation response of thoracic spines under DVR maneuvers until failure, and compare to pure-moment testing of same spines. Despite reports of surgical complications, few studies exist on increase in ROM under DVR torque. Biomechanical models predicting increases from surgical releases have consistently used "pure-moments", a standard established for non-destructive measurement of ROM. Yet, DVR torque is not accurately modeled using pure moments and, moreover, magnitudes of torque applied during DVR maneuvers may be substantially higher than pure-moment testing.

METHODS

Cadaveric thoracic spines (N = 11) were imaged, then prepared. Polyaxial pedicle screws were implanted at T7-T10 after surgical releases. Bilateral facetectomies and Ponte osteotomies were completed at T10-T11. A custom apparatus, mounted into an 8-dof MTS load frame, was used to attach to pedicle screws, allowing simulation of surgical DVR maneuvers. Motions of vertebrae were measured using optical motion tracking. Torque was increased until rupture of the T10-T11 disc or fracture at the pedicle screw sites at any level. The torque-rotation behavior was compared to its behavior under pure-moment testing performed prior to the DVR maneuver.

RESULTS

Under DVR maneuvers, failure of the T10-T11 discs accompanied in most cases by pedicle screw loosening, occurred at 13.7-54.7 Nm torque, increasing axial rotation by 1.4°-8.9°. In contrast, pure-moment testing (4 Nm) increased axial rotation by only 0.0°-0.9°.

CONCLUSIONS

DVR resulted in substantially greater correction potential increases compared to pure-moment testing even at the same torque. These results suggest increased flexibility obtained by osteotomies and facetectomies is underestimated using pure-moment testing, misrepresenting clinical expectations. The present study is an important and necessary step toward the establishment of a more accurate and ultimately surgically applied model.

LEVEL OF EVIDENCE

III.

Iliotibial band autograft: what size is the graft? A mathematical and cadaveric model : ITB single and double strand size

BACKGROUND

The iliotibial band (ITB) is used in anterior cruciate ligament (ACL) reconstruction in skeletally immature patients as well as several other orthopedic reconstructions. The purpose of this study is to determine the size of the ITB as an autograft option in ACL reconstruction surgery or other orthopedic soft tissue reconstructions.

METHODS

Five adult cadavers resulting in nine ITB were used. Thickness and width of the ITB were determined. Using ITB width of 15-60 mm, single and doubled graft sizes were determined using standard surgical graft size technique. Geometric calculations based on average graft thickness were used to mathematically confirm the graft size of the ITB.

RESULTS

The ITB is less than 1 mm in thickness in males and females. Cadaveric measurements were less than 1 mm larger than mathematical measurements, in majority of measurements. ITB autograft can be harvested to a maximum 9 mm single-stranded graft or > 12 mm doubled graft. A minimum of 50 mm of ITB width is required to make a 8 mm graft.

CONCLUSIONS

ITB is a versatile graft that can be used for a graft size up to 9 mm single strand and over 12 mm double strand. A minimum of 50 mm width of ITB is required to obtain a 8 mm-diameter autograft. To ensure appropriate graft size, surgeons should consider harvesting the maximum amount of ITB when performing ACL reconstructions in skeletally immature patients.

CLINICAL RELEVANCE

Surgeons have a quick reference for the width of ITB they should harvest based on the size of graft they require for a successful surgery.

Vitamin D sterols increase FGF23 expression by stimulating osteoblast and osteocyte maturation in CKD bone

Impaired osteoblast and osteocyte maturation contribute to mineralization defects and excess FGF23 expression in CKD bone. Vitamin D sterols decrease osteoid accumulation and increase FGF23 expression; these agents also increase osteoblast maturation in vitro but a link between changes in bone cell maturation, bone mineralization, and FGF23 expression in response to vitamin D sterols has not been established. We evaluated unmineralized osteoid accumulation, osteocyte maturity markers (FGF23: early osteocytes; sclerostin: late osteocytes), and osteocyte apoptosis in iliac crest of 11 pediatric dialysis patients before and after 8 months of doxercalciferol therapy. We then evaluated the effect of 1,25(OH)2vitamin D on in vitro maturation and mineralization of primary osteoblasts from dialysis patients. Unmineralized osteoid accumulation decreased while numbers of early (FGF23-expressing) increased in response to doxercalciferol. Osteocyte apoptosis was low but increased with doxercalciferol. Bone FGF23 expression correlated with numbers of early, FGF23-expressing, osteocytes (r = 0.83, p < 0.001). In vitro, 1,25(OH)2vitamin D increased expression of the mature osteoblast marker osteocalcin (BGLAP) but only very high (100 nM) concentrations affected in vitro osteoblast mineralization. High doses (10 and 100 nM) of 1,25(OH)2vitamin D also increased the ratio of RANKL/OPG expression in CKD osteoblasts. Vitamin D sterols directly stimulate osteoblast maturation. They also increase osteocyte turnover and increase osteoblast expression of osteoclast differentiation factors, thus likely modulating osteoblast/osteoclast/osteocyte coupling. By increasing numbers of early osteocytes, vitamin D sterols increase FGF23 expression in CKD bone.

Hamstring Autograft Too Small: How Much Allograft Do You Need to Supplement to a Desired Hybrid Graft Size?

PURPOSE

To determine a simple rule for choosing supplemental allograft size for hybrid anterior cruciate ligament reconstruction using mathematical and cadaveric models.

METHODS

Mathematical and cadaveric models were used to determine the rule. The mathematical model required application of the geometric Pythagorean theorem to add areas of circles. Cadaveric semitendinosus and gracilis tendons were combined in multiple quadrupled hamstring size combinations and then sized using standard surgical techniques to confirm the mathematical model.

RESULTS

Geometric measurement, not simple addition, of graft diameters was required to determine the final graft size. Direct comparison of cadaveric and mathematical models showed close relations. If a final graft size of 7 mm is desired, an added diameter of all grafts of approximately 9.5 mm is needed. If a final graft size of 8 mm is desired, an added diameter of all grafts of approximately 11 mm is needed. If a final graft size of 9 mm is desired, an added diameter of all grafts of approximately 12.5 mm is needed. If a final graft size of 10 mm is desired, an added graft diameter of approximately 14 mm is needed. Cadaveric hamstring measurements were similar to the mathematical model.

CONCLUSIONS

By use of mathematical and cadaveric models, simple rules for determining the additional size of allograft diameter needed to supplement undersized hamstring autograft were created.

CLINICAL RELEVANCE

With the increasing availability of allograft types and sizes, surgeons currently have no guidelines on the size of allograft that is required to supplement an undersized hamstring autograft. Simple rules were created for determining the amount of allograft supplementation required for undersized hamstrings and are easily applied to clinical situations.

Opioid Prescription and Usage in Adolescents Undergoing Orthopaedic Surgery in the United States: A Systematic Review

BACKGROUND

The proper use of opioid analgesia for postoperative pain management is controversial. While opioids are considered the standard of care for multimodal postoperative pain modulation in the United States, there is a lack of established protocols for prescribing opioids in adolescents undergoing outpatient orthopaedic surgery. The objective of this review was to identify and report on current literature on opioid prescription for pain management in adolescents undergoing all procedures, as well as in adults undergoing outpatient orthopaedic surgery.

METHODS

A comprehensive literature search using PRISMA guidelines was performed to identify all articles relevant to opioid use in adolescents for postoperative pain and in adults following outpatient orthopaedic procedures.

RESULTS

A total of 4,446 results were identified from databases and relevant journal web sites. Of these, 9 articles were selected that fit the criteria for review. Five studies discussed the dosage and type of opioids prescribed in adolescent populations, and 4 quantified patient self-administration in adult populations.

CONCLUSIONS

Adolescent opioid pain management following outpatient orthopaedic surgery is not documented. Current recommendations for opioid prescription in adolescents lack support and are primarily based on adult dosages. Adult studies suggest that opioid medications may be overprescribed following outpatient orthopaedic surgery. These results clearly indicate that there is a pressing need for quantitative research on pain management following outpatient orthopaedic surgery in the adolescent population in the United States.

CLINICAL RELEVANCE

There appear to be no studies on self-administered opioid pain medication following orthopaedic surgery in an adolescent population, suggesting that there is no objective basis for the current prescription recommendations.

Challenging the Conventional Standard for Thoracic Spine Range of Motion: A Systematic Review

BACKGROUND

Segmental motion is a fundamental characteristic of the thoracic spine; however, studies of segmental ranges of motion have not been summarized or analyzed. The purpose of the present study was to present a summary of the literature on intact cadaveric thoracic spine segmental range of motion in each anatomical plane.

METHODS

A systematic MEDLINE search was performed with use of the terms "thoracic spine," "motion," and "cadaver." Reports that included data on the range of motion of intact thoracic human cadaveric spines were included. Independent variables included experimental details (e.g., specimen age), type of loading (e.g., pure moments), and applied moment. Dependent variables included the ranges of motion in flexion-extension, lateral bending, and axial rotation.

RESULTS

Thirty-three unique articles were identified and included. Twenty-three applied pure moments to thoracic spine specimens, with applied moments ranging from 1.5 to 8 Nm. Estimated segmental range of motion pooled means ranged from 1.9° to 3.8° in flexion-extension, from 2.1° to 4.4° in lateral bending, and from 2.4° to 5.2° in axial rotation. The sums of the range of motion pooled means (T1 to T12) were 28° in flexion-extension, 36° in lateral bending, and 45° in axial rotation.

CONCLUSIONS

The pooled ranges of motion were similar to reported in vivo motions but were considerably smaller in magnitude than the frequently referenced values reported prior to the widespread use of biomechanical testing standards. Improved reporting of biomechanical testing methods, as well as specimen health, may be beneficial for improving on these estimations of segmental cadaveric thoracic spine range of motion.

Strength of Thoracic Spine Under Simulated Direct Vertebral Rotation: A Biomechanical Study

BACKGROUND

Direct vertebral rotation (DVR) has gained increasing popularity for deformity correction surgery. Despite large moments applied intraoperatively during deformity correction and failure reports including screw plow, aortic abutment, and pedicle fracture, to our knowledge, the strength of thoracic spines has been unknown. Moreover, the rotational response of thoracic spines under such large torques has been unknown.

PURPOSE

Simulate DVR surgical conditions to measure torsion to failure on thoracic spines and assess surgical forces.

STUDY DESIGN

Biomechanical simulation using cadaver spines.

METHODS

Fresh-frozen thoracic spines (n = 11) were evaluated using radiographs, magnetic resonance imaging (MRI) and dual-energy x-ray absorptiometry. An apparatus simulating DVR was attached to pedicle screws at T7-T10 and transmitted torsion to the spine. T11-T12 were potted and rigidly attached to the frame. Strain gages measured the simulated surgical forces to rotate spines. Torsional load was increased incrementally till failure at T10-T11. Torsion to failure at T10-T11 and corresponding forces were obtained.

RESULTS

The T10-T11 moment at failure was 33.3 ± 12.1 Nm (range = 13.7-54.7 Nm). The mean applied force to produce failure was 151.7 ± 33.1 N (range = 109.6-202.7 N), at a distance of approximately 22 cm where surgeons would typically apply direct vertebral rotation forces. Mean right rotation at T10-T11 was 11.6°±5.6°. The failure moment was significantly correlated with bone mineral density (Pearson coefficient 0.61, p = .047). Failure moment also positively correlated with radiographic degeneration grade (Spearman rho > 0.662, p < .04) and MRI degeneration grade (Spearman rho = 0.742, p = .01).

CONCLUSION

The present study indicated that with the advantage of lever arms provided with DVR techniques, relatively small surgical forces, <200 N, can produce large moments that cause irreversible injury. Although further studies are required to establish the safety of surgical deformity correction surgeries, the present study provides a first step in the quantification of thoracic spine strength.

Osteocartilaginous transfer of the proximal part of the fibula for osseous overgrowth in children with congenital or acquired tibial amputation: surgical technique and results

BACKGROUND

Osseous overgrowth is a common problem in children after tibial transcortical amputation. We present the results of forty-seven children (fifty tibiae) treated for tibial osseous overgrowth with an autologous osteocartilaginous cap from the proximal part of the ipsilateral fibula.

METHODS

We reviewed the records of all patients who underwent amputation at a single pediatric hospital from 1990 to 2011. All patients who had been followed for a minimum of two years after undergoing osteocartilaginous capping with the proximal part of the ipsilateral fibula to treat established tibial overgrowth were included. Patients with acquired and congenital amputations were compared.

RESULTS

Fifty tibiae in forty-seven patients met our inclusion criteria. There were thirty-one acquired and nineteen congenital amputations. The mean age at surgery was 7.6 years (range, 2.1 to 15.6 years), and the mean duration of follow-up was 7.2 years (range, 2.2 to 15.4 years). Five tibiae (10%) in four patients had recurrence of the overgrowth at a mean of 5.4 years (range, 2.8 to 7.6 years) after the osteocartilaginous transfer. There was no significant difference in the results between children with an acquired amputation and those with a congenital amputation.

CONCLUSIONS

At a mean of 7.2 years after autologous osteocartilaginous capping with the proximal part of the fibula, 90% of the limbs had not had recurrent overgrowth. This is a safe and effective treatment of long-bone overgrowth following either congenital or acquired amputation in children.

Primary osteoblast-like cells from patients with end-stage kidney disease reflect gene expression, proliferation, and mineralization characteristics ex vivo

Osteocytes regulate bone turnover and mineralization in chronic kidney disease. As osteocytes are derived from osteoblasts, alterations in osteoblast function may regulate osteoblast maturation, osteocytic transition, bone turnover, and skeletal mineralization. Thus, primary osteoblast-like cells were cultured from bone chips obtained from 24 pediatric ESKD patients. RNA expression in cultured cells was compared with RNA expression in cells from healthy individuals, to RNA expression in the bone core itself, and to parameters of bone histomorphometry. Proliferation and mineralization rates of patient cells were compared with rates in healthy control cells. Associations were observed between bone osteoid accumulation, as assessed by bone histomorphometry, and bone core RNA expression of osterix, matrix gla protein, parathyroid hormone receptor 1, and RANKL. Gene expression of osteoblast markers was increased in cells from ESKD patients and signaling genes including Cyp24A1, Cyp27B1, VDR, and NHERF1 correlated between cells and bone cores. Cells from patients with high turnover renal osteodystrophy proliferated more rapidly and mineralized more slowly than did cells from healthy controls. Thus, primary osteoblasts obtained from patients with ESKD retain changes in gene expression ex vivo that are also observed in bone core specimens. Evaluation of these cells in vitro may provide further insights into the abnormal bone biology that persists, despite current therapies, in patients with ESKD.

Outcomes of lower extremity orthopedic surgery in ambulatory children with cerebral palsy with and without gait analysis: results of a randomized controlled trial

This study examined the impact of gait analysis on surgical outcomes in ambulatory children with cerebral palsy (CP) through a randomized controlled trial. 156 children with CP (94 male; age 10.2 ± 3.7 years) underwent gait analysis and were randomized to two groups: Gait Report group (N = 83), where the referring surgeon received the patient's gait analysis report, and Control group (N = 73), where the surgeon did not receive the gait report. Outcomes were assessed pre- and 1.3 ± 0.5 years post-operatively. An intent-to-treat analysis compared outcomes between the two groups. Outcome measures included the Gillette Functional Activity Questionnaire (FAQ), Gait Deviation Index (GDI), oxygen cost, gross motor function measure, Child Health Questionnaire (CHQ), Pediatric Outcomes Data Collection Instrument (PODCI), and Pediatric Evaluation and Disability Inventory. The outcomes that differed significantly between groups were change in health from the CHQ, which was rated as much better for 56% (46/82) of children in the Gait Report group compared with 38% (28/73) in the Control group (p = 0.04), and upper extremity physical function from the PODCI. Gait outcomes (FAQ and GDI) improved more when over half of the recommendations for a patient were followed or the recommended extent of surgery (none, single, or multi-level) was done (p ≤ 0.04). On average, however, only 42% of the recommendations were followed in the Gait Report group, compared with 35% in the Control group (p = 0.23). This is much less than the >85% reported in previous studies and may account for the lack of differences between groups for some of the outcome measures.

Quantification of Increase in Three-dimensional Spine Flexibility Following Sequential Ponte Osteotomies in a Cadaveric Model

BACKGROUND

Posterior-only procedures are becoming more popular for treatment of rigid adolescent idiopathic scoliosis, but little is known about the quantitative correction potential for Ponte osteotomies. The objective of this study was to quantify and compare the range of motion of intact multilevel thoracic spine segments with the same segments after each of 3 sequential Ponte osteotomies.

METHODS

We tested 5 human cadaveric thoracic spine segments, spanning T-T6, or T7-T12, in an 8-degree-of-freedom servo-hydraulic load frame, monitoring motion of each vertebra with an optical motion tracker. We measured range of motion while we applied cyclic, pure moment loading to produce flexion-extension, lateral bending, and axial rotation at a rate of 0.5°/second, to a maximum of ± 6 Nm. Each specimen was tested intact and after each of 3 sequential Ponte osteotomies.

RESULTS

Total range of motion for the segments (either T2-T5 or T8-T11) increased by as much as 1.6° in flexion, 1.5° in extension, 0.5° in lateral bending, and 2.8° in axial rotation with each osteotomy. Because of the variation in initial specimen stiffness, we normalized motions to the intact values. In flexion, average range of motion increased after each osteotomy compared with intact, by 33%, 56%, and 69%. In extension, slightly smaller increases were seen, increasing by as much as 56% after the third osteotomy. In lateral bending, Ponte osteotomies had little effect on range of motion. In axial rotation, range of motion increased by 16%, 29%, and 65% after 3 osteotomies.

CONCLUSIONS

Sequential Ponte osteotomies increased range of motion in flexion, extension, and axial rotation, but not in lateral bending. These results suggest that the Ponte osteotomy may be appropriate when using derotational correction maneuvers, or to improve apical lordosis at the apex of curvature during posterior spinal fusion procedures. Although these techniques are effective in gaining correction for kyphotic deformities and rigid curvatures, they add time and blood loss to the procedure.

Influence of gait analysis on decision-making for lower extremity orthopaedic surgery: Baseline data from a randomized controlled trial

Previous studies examining the influence of gait analysis on surgical decision-making have been limited by the lack of a control group. The aim of this study was to use data from a randomized controlled trial to determine the effects of gait analysis on surgical decision-making in children with cerebral palsy (CP). 178 ambulatory children with CP (110 male; age 10.3±3.8 years) being considered for lower extremity orthopaedic surgery underwent gait analysis and were randomized into one of two groups: gait report group (N=90), where the orthopaedic surgeon received the gait analysis report, and control group (N=88), where the surgeon did not receive the gait report. Data regarding specific surgeries were recorded by the treating surgeon before gait analysis, by the gait laboratory surgeon after gait analysis, and after surgery. Agreement between the treatment done and the gait analysis recommendations was compared between groups using the 2-sided Fisher's Exact test. When a procedure was planned initially and also recommended by gait analysis, it was performed more often in the gait report group (91% vs. 70%, p<0.001). When the gait laboratory recommended against a planned procedure, the plan was changed more frequently in the gait report group (48% vs. 27%, p=0.009). When the gait laboratory recommended adding a procedure, it was added more frequently in the gait report group (12% vs. 7%, p=0.037). These results provide a stronger level of evidence demonstrating that gait analysis changes treatment decision-making and also reinforces decision-making when it agrees with the surgeon's original plan.

Agreement among three instruments for measuring functional health status and quality of life in pediatric orthopaedics

The Child Health Questionnaire (CHQ), Pediatric Outcomes Data Collection Instrument (PODCI), and Pediatric Evaluation and Disability Inventory (PEDI) are the 3 instruments commonly used to measure function and quality of life in pediatric orthopaedics. This study compared answers to specific questions on the CHQ, PODCI, and PEDI given by the parents of 66 children with cerebral palsy, who completed all 3 questionnaires. Both Spanish- and English-speaking subjects were included. No overlapping questions were found between the CHQ and PEDI. Of the 8 questions that overlapped between the CHQ and PODCI, 2 questions (general health and change in health) had weighted kappa greater than 0.70, with responses within +/-1 point for more than 95% of respondents. These 2 questions had almost exactly the same wording on both questionnaires. The other 6 questions had fair to poor agreement between questionnaires (kappa, 0.10-0.55). All 5 questions that were addressed by both the PODCI and PEDI also had poor agreement (kappa < 0.40). There was little correspondence between the preconceived match quality and the actual matching results (r=0.41; P=0.16). These results suggest that differences in wording have a significant and unpredictable effect on parents' responses; this should be considered when selecting from among different instruments. Of the instruments used in this study, the CHQ is the easiest to administer and is a good general quality of life measure; however, the PODCI or PEDI may be preferred if information about more specific functional activities is desired.

Body mass index and Blount disease

As the increasing prevalence of overweight and obese children is approaching epidemic proportions in North America, this study was designed to investigate whether Body Mass Index (BMI) and age- and gender-specific percentile Body Mass Index (BMI %) are associated with the likelihood of being listed for surgery for Blount disease after initial presentation to a tertiary referral centre. In a restrospective consecutive sample of 102 children with an average age of 5.9 +/- 4.3 years, it was determined that there was a significant association between BMI and BMI% and being listed for surgery, after adjusting for the effects of the child's age and gender, with mean odds ratios of 1.30 (95% confidence interval 1.02-1.60) and 1.05 (95% confidence interval 1.01-1.09) respectively. When the sample was subgrouped into infantile (less than 3 years of age) and late-onset (greater than 3 years of age), BMI and BMI% were still significantly associated with the children being listed for surgery in the late-onset group with mean odds ratios 2.75 (95% confidence interval 1.03-7.33) and 1.09 (95% confidence interval 1.01-1.18) respectively. However, of the two measures only the BMI was significant in the infantile group with an odds ratio of 1.27 (95% confidence interval 1.01-1.60). Should these associations be real then measures aimed at decreasing weight in children may have some effect on the number of children undergoing surgery for the treatment of Blount disease.

Transient meralgia paresthetica after pediatric posterior spine fusion

Meralgia paresthetica (MP) rarely occurs during posterior spine surgery. The study goal was to examine risk factors associated with the incidence of MP. A review of 56 consecutive pediatric patients undergoing posterior spine fusion for scoliosis was performed. Patients with abnormal sensation in the lateral thigh preoperatively and prior spine surgery were excluded. All patients were positioned prone on the Jackson (Orthopaedic Systems, Inc., Union City, CA) spinal table with either (1) the lower leg support table and thigh supports or (2) the lower leg suspension sling. Data on patient weight, diagnosis, surgeon, duration of surgery, presence of MP, symptoms, and symptom duration were collected. A logistic regression analysis was performed between independent variables and presence of MP. There were 10/56 patients with MP (18%). Symptoms were anterolateral thigh numbness without pain or weakness. Symptoms in all cases were resolved, on average, before the 6-week postoperative visit (range 2-24 weeks). Patients with MP more often had idiopathic scoliosis (28% vs 7%; P < 0.05) were positioned with the lower leg sling instead of the flat table support (31% vs 13%; P < 0.05) and trended toward longer surgery times (451 vs 388 minutes; NS). Abnormal body mass index, age at surgery, surgeon, and sex did not correlate to MP. MP can occur after pediatric posterior spine surgery. Symptoms were minor, temporary, and did not require treatment. Shorter surgical times and use of thigh pads in conjunction with the lower leg support table may decrease the incidence of MP.

Radiographic outcome of soft-tissue surgery for hip subluxation in non-ambulatory children with cerebral palsy

This study reviewed radiographs of non-ambulatory spastic tetraparetic cerebral palsy patients who underwent soft tissue hip surgery to address hip subluxation. Patients were under 10 years of age at surgery, had limited hip motion, and radiographic subluxation. At an average 7.4 years postoperatively, hips had a migration percentage in the normal range (0-15%) in 58 of 70 cases (83%). Hips with preoperative subluxation between 30 and 49% had a normal migration percentage in 18 of 21 cases (81%), and those over 50% in three of seven (43%) of cases. Soft tissue surgery alone, even in cases of moderate hip subluxation, can result in long-term radiographic hip stability.

Outcomes of lengthening short lower-extremity amputation stumps with planar fixators

Patients with short lower-extremity amputation stumps exhibit poor prosthetic fit and inefficient gait. Often they are fit at the next-higher prosthetic level, increasing energy consumption. This study aimed to characterize the risk/benefit ratio of stump lengthening with planar external fixators. All patients lengthened for functionally short amputation stumps were reviewed. Outcome measures included changes in prosthetic use, soft tissue problems, qualitative gait analysis, and surgical complications. Patients averaged 15.1 years of age at surgery, with 4.1 years of follow-up. The average lengthening index was 9.2 mm/mo. Femoral lengthenings obtained more length (8.7 vs. 6.9 cm). After treatment, prosthetic skin-related complications decreased and qualitative gait parameters improved. Most (85%) wore a standard prosthesis for their amputation level after surgery, whereas none could before. There were 1.4 complications per patient, all successfully surgically treated. Lengthening is time-consuming and associated with frequent complications but results in improved gait and energy consumption.

Midshaft clavicle fractures associated with atlantoaxial rotatory displacement: a report of two cases

Two cases of clavicle fractures associated with atlantoaxial rotatory displacement as well as 11 additional cases from the literature are presented. Most cases occur in girls 6 to 10 years old. The head is most often laterally bent toward and rotated away from the fractured clavicle. There is often a delay in making the diagnosis, which is best demonstrated by dynamic CT. Treatment of the clavicle fracture is straightforward, but failure to recognize and treat the C1-2 rotatory displacement promptly can lead to fixed C1-2 deformity. Displacement recognized within the first 3 weeks of injury can be successfully treated nonoperatively. A delay of 6 weeks or greater in the diagnosis leads to fixed deformity at C1-2 that can be addressed with a limited cervical fusion.

Outcome of slipped capital femoral epiphysis in renal osteodystrophy

The cases of renal osteodystrophy-associated slipped capital femoral epiphysis in 11 consecutive patients were reviewed. Nine patients had bilateral involvement, totaling 20 hips. The mean age at presentation was 10.6 years. Slip location was physeal in 13 and metaphyseal in seven hips. All patients had prompt medical treatment of their bone disease, and nine patients underwent surgical stabilization. Fixation consisted of multiple custom-machined Steinmann pins that were smoothed distally but threaded proximally, allowing continued proximal femoral growth. The mean radiographic and clinical follow-up was 5.7 years and 9.1 years, respectively. Slips stabilized in 14 of 16 operated hips (88%), whereas one patient with inadequate renal disease control had slip progression requiring subsequent subtotal parathyroidectomy and repeat fixation. Combined medical management and surgery with custom-machined pins prevented slip progression while allowing continued physeal growth.

The impact of mixed components on polyethylene wear

Wear rates were measured in 50 mixed and 71 matched total hip arthroplasties with > or = 3-year follow-up to determine whether implanting mixed hip components increased polyethylene wear. Average patient age was 61 years for the mixed group and 57 years for the matched group. Average radiographic follow-up was 5.8 years and 6.8 years, respectively. The average linear wear rate for the mixed and matched groups was 0.11 mm/y. Therefore, implanting same-size, total hip components from different manufacturers did not lead to large increases in polyethylene wear.

Relative tibial and femoral varus as a predictor of progression of varus deformities of the lower limbs in young children

Many young children present to pediatric orthopaedic surgeons with genu varum and mild beaking of the medial metaphysis on x-ray. Predicting whether these deformities will progress is challenging. In addition, there is no consensus as to whether these children should all be classified as having Blount disease. To avoid this latter problem, the authors included in this study all children presenting with bowed legs, regardless of diagnosis. With the aim of improving the ability to predict progression, the authors tested the hypothesis that patients with progression have more tibial than femoral varus. The authors reviewed 173 varus limbs of 98 patients younger than 4 years old. The authors determined the angular deformity in both femur and tibia by measuring the angles between their mechanical axes and the transverse axis of the knee, and determined the contribution of tibial deformity as a percentage of the total (%DT). The metaphyseal-diaphyseal angles of the tibia (MDA) were also measured to compare the value of that test with the %DT. There were 22 limbs with progressive and 141 limbs with resolving varus. Both the MDA and %DT were significantly different between groups. Tibial varus was found to exceed femoral varus in all patients with progression and also in several patients whose deformity resolved spontaneously. Although more specific and more sensitive than the MDA, the %DT is a good, but not perfect, predictor of progression. However, all patients in this series with both a %DT >50% and an MDA of 16 degrees or greater went on to progress. Using both of these tests together may therefore provide the surgeon with a reliable indicator of the children who would benefit from surgical correction.

Osteochondral lesions of the capitellum in pediatric patients: role of magnetic resonance imaging

The role of magnetic resonance imaging (MRI) in the evaluation of patients with osteochondral lesions of the capitellum is undefined. To define its role, the cases of nine consecutive children with 11 capitellar osteochondral lesions who underwent MRI were reviewed. Magnetic resonance imaging accurately delineated the size of the osteochondral lesions and identified capitellar loose bodies not seen on plain radiographs in two elbows. In patients without capitellar loose bodies, two distinct MRI patterns existed that were similar to those seen in femoral head osteonecrosis. Magnetic resonance imaging aided in the treatment of children with osteochondral lesions of the capitellum. Further studies are necessary to define the significance of the two MRI patterns.

Efficacy of nonoperative treatment for lateral epicondylitis

One hundred cases of lateral epicondylitis among 97 patients were reviewed, and 84 patients were contacted for long-term follow-up. Patients participated in a structured nonoperative treatment regimen. Mean age of contacted patients was 49 years; mean follow-up was 2.8 years. Surgery was averted in 65 (75%) of 87 cases. Patients who achieved pain control after only 1 cortisone injection successfully avoided surgery 88% of the time, whereas those requiring multiple injections avoided surgery only 44% of the time. Eventual outcomes were similar, regardless of treatment type. Patients requiring multiple cortisone injections to alleviate acute pain have a guarded prognosis for continued nonoperative management.

On and off the playing field: ethics in medicine

The sportscasters' metaphor, "on and off the playing field," is used to describe the altruistic demeanor of good ethical and moral behavior and empathy toward patients that is required of medical students and physicians. It has been noted that these altruistic qualities often compete unsuccessfully with scientific skills and scholarly pursuits. Many schools hold the "White Coat Ceremony" annually and host a chapter of the Honor Medical Society to instill these traits in students. Teaching of altruistic demeanor is most successful using a combination of techniques, which include philosophy, virtue theory, small-group discussions using case vignettes, and the structured objective clinical examination with "standardized patients." On the playing field, current major issues are intellectual honesty, mandatory testing/treatment for HIV/AIDS, abortion, end-of-life issues, and gene therapy. Off the playing field, family, religion, community service, and leadership will immortalize medical students in the mythical Health Care Hall of Fame.

The use of occupational therapists in independent living programs

OBJECTIVES

Occupational therapy literature describes various independent living programs developed by occupational therapists and at times documents their effectiveness, yet none of the literature reviewed examined the involvement of occupational therapists in independent living programs.

METHOD

Directors of independent living programs in the United States were surveyed to ascertain their use of occupational therapists, to discover which disciplines were providing traditional occupational therapy services (e.g., daily living skills, assistive device provision, etc.) in these programs, and to identify which types of independent living programs were more likely to use occupational therapy services.

RESULTS

Less than half of the 96 responding independent living programs (46%) reported using occupational therapy services, and those programs that did provide occupational therapy services did so at a minimal rate. The programs that employed occupational therapists offered traditional occupational therapy services more often than those with no occupational therapists, but frequently, occupational therapists were not the providers of these traditional occupational therapy services. Chi-square analyses indicated that an independent living program's use of occupational therapy services was significantly affected by the type of facility (p = 0.05), the primary funding source (p = 0.04), and the program's practices regarding the hiring of professionals without disabilities (p = 0.04).

CONCLUSION

Possible reasons why occupational therapists are not employed more by independent living centers are discussed and recommendations for change are provided.

The development of subsensitivity to atropine methylnitrate. A double-blind, placebo-controlled crossover study

This is a double-blind, placebo-controlled crossover study designed to assess the effectiveness of nebulized atropine methylnitrate (AMN) with chronic use. We studied 22 patients with asthma, 10 receiving theophylline and inhaled beta-agonists and 12 who were receiving corticosteroids as well. All had demonstrated at least a 15% change in FEV1 either spontaneously or after bronchodilator. Bronchodilator effect was measured serially for 4 h after inhalation of the initial dose and again after 2 wk of four-times-daily use. Significant bronchodilator effect was seen initially with AMN when compared to placebo (p less than 0.01). After 2 wk of use, the bronchodilator effect of AMN was significantly diminished as compared to the initial effect (p less than 0.01) but was still better than placebo (p less than 0.05). Subsensitivity did develop to varying degrees in the patients, but we were unable to identify any clinical parameters that would allow prediction of subsequent subsensitivity. We conclude that the development of subsensitivity to AMN occurs in certain patients with chronic administration but does not reflect a total loss of bronchodilator effect.

Wounding potential of the Russian AK-74 assault rifle

The Russian contribution to the new generation of smaller caliber assault rifles is the AK-74, whose 5.61-mm (diameter), 3.4-gm (weight), 2.5-cm (length) aerodynamically shaped bullet has a muzzle velocity of 900 m/s. Our tests show that in living swine soft tissues and gelatin tissue simulant the AK-74's copper-plated steel jacket resists fragmentation or deformation. Since the bullet does not fragment, the tissue disruption surrounding the bullet pathway is limited to the stretching effect of temporary cavitation. We present evidence indicating that the energy used during temporary cavity formation causes limited permanent tissue disruption in the more elastic soft tissues (muscle, bowel wall, lung); the same insult in the relatively nonelastic liver, however, causes multiple fractures and massive permanent disruption. We conclude that the AK-74, despite its rather high velocity and marked tendency to yaw soon after penetration, causes relatively nondramatic wounds due to its nonfragmenting behavior.

Bullet fragmentation: a major cause of tissue disruption

Effects of nonfragmenting solid brass bullets (5.56 mm, 3.1 gm, 1.9 cm long, machine-made at Letterman Army Institute of Research) and fragmenting soft-point bullets (5.56 mm, 3.2 gm, 1.7 cm long, commercially made by Hornady Manufacturing Co., Grand Island, NE) were compared when they were fired through soft tissue of the hind legs of five live swine (50 to 70 kg). The swine were anesthetized endotracheally (0.8% halothane) and placed in the supine position with the hind legs extended. Blocks of tissue simulant (10% gelatin at 4 degrees C, molded in blocks 20 X 22 X 47 cm) were placed against the skin at the predicted point of bullet exit. All shots (a fragmenting bullet through one hind leg and a nonfragmenting bullet through the other hind leg of each swine) were fired at a range of 3 m from a rifle with a bullet tract at 90 degrees to the long axis of the swine's body. Bullet velocities ranged from 930 to 990 m/s. Dissections of the bullet tract (through tissue and gelatin) revealed that tissue disruption from the fragmenting bullets was significantly greater (p less than 0.001) than from nonfragmenting bullets. The recovered bullets were weighed. The results showed that the fragmenting bullet lost 59 to 77% of its original weight and the nonfragmenting bullet was the same weight as originally. Recognition of the amount of tissue disruption and identification of bullet fragments in the wounds resulting from the two different bullets should be a useful guide to operating surgeons in selecting the best approach for treatment of gunshot injuries.

ARDS associated with the use of sympathomimetics and glucocorticoids for the treatment of premature labor

A 19-yr-old woman developed adult respiratory distress syndrome (ARDS) in the postnatal period after treatment with dexamethasone and ritodrine for premature labor. An assay of complement activation was positive, suggesting a possible mechanism for this patient's ARDS.

The ultrastructure of polyploid B-cells in the islets of normal mice

Light and electron microscopic studies of diploid, tetraploid and octaploid B-cells in the islets of normal C57BL/KsJ mice revealed that polyploid cells were characterized by a wider range of granulated states than diploid B-cells. The maximum granule densities were similar for polyploid and diploid cells; however, some polyploid cells were almost devoid of granules, while the least granulated diploid cells contained intermediate granule densities. The tetraploid cell also appeared to be characterized by an increased mitochondrial stage which suggests compensation for the greater degree of degranulation. These observations were confirmed by morphometric analysis. Two interpretations of the apparent polyploidy are discussed; that polyploid B-cells may be more responsive to insulin releasing stimuli than diploid B-cells and that tetraploid cells may only be diploid cells in the G2 phase of the mitotic cycle.