The Longitudinal Effects of Posterior Spinal Fusion with Derotation on Axial Deformity in Adolescent Idiopathic Scoliosis

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To characterize the change in angle of trunk rotation (ATR), axial vertebral rotation (AVR), and body surface rotation (BSR) in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion (PSF) with en-bloc derotation across multiple postoperative visits.

SUMMARY OF BACKGROUND DATA

Previous research has documented ATR, AVR, and BSR correction for AIS patients after surgery. However, there is a lack of evidence on the sustainability of this correction over time.

METHODS

This was a retrospective study from a single-center prospective surface topographic registry of patients with AIS, age 11-20 at time of surgery, who underwent PSF with en-bloc derotation. Patients with previous spine surgery were excluded. ATR was measured with a scoliometer, AVR through EOS radiographic imaging, and BSR via surface topographic scanning, Data collection occurred at: preoperative, six-week, three-month, six-month, one-year, and two-year postoperative visits. BSR and AVR were tracked at the preoperative apical vertebral level, and the level with maximum deformity, at each respective timepoint. Generalized estimating equations models were used for statistical analysis. Covariates included age, sex, and body mass index.

RESULTS

49 patients (73.4% female, mean age 14.6±2.2 years, mean preoperative coronal curve angle 57.9°±8.5, and 67% major thoracic) were evaluated. ATR correction was significantly improved at all postoperative timepoints and there was no significant loss of correction. AVR Max and AVR Apex were significantly improved at all timepoints but there was a significant loss of correction for AVR Apex between the six-week and one-year visit (P=0.032). BSR Max achieved significant improvement at the three-month visit. BSR Apex was significantly improved at the three-month and one-year visit.

CONCLUSION

ATR and AVR demonstrated significant axial plane correction at two-years postoperative in patients undergoing PSF for AIS. BSR did not maintain significant improvement by the two-year visit.

Hemiepiphysiodesis for Genu Valgum in Patients With Multiple Hereditary Exostoses

BACKGROUND

Genu valgum is a well-known feature of multiple hereditary exostoses (MHE). Though prior reports have demonstrated successful treatment with hemiepiphysiodesis, details regarding the correction rate and comparison to an idiopathic population are lacking. This study aimed to detail our institution's experience with guided growth of the knee in patients with MHE and compare this to an idiopathic population.

METHODS

All pediatric patients (age 18 and younger) with MHE who underwent lower extremity hemiepiphysiodesis at a tertiary care medical center between January 2016 and December 2022 were retrospectively reviewed. Preoperative and postoperative mechanical lateral distal femoral angle (mLDFA) and medial proximal tibial angle (MPTA, the primary outcomes) were measured in addition to mechanical axis deviation (MAD) and hip-knee-ankle angle (HKA). Patients were 1:2 matched based on age, sex, and physes instrumented to a cohort with idiopathic genu valgum.

RESULTS

A total of 21 extremities in 16 patients with MHE underwent hemiepiphysiodesis of the distal femur, proximal tibia, and/or distal tibia. The mean age at surgery was 11.7±2.2 years. Mean MAD corrected from zone 1.9±0.7 to -0.3±1.5, while mLDFA corrected from 83.4±2.9 to 91.7±5.2 degrees and MPTA corrected from 95.3±3.6 to 90.5±4.0 degrees in distal femurs and proximal tibias undergoing guided growth, respectively. Three extremities (14.3%) experienced overcorrection ≥5 degrees managed with observation. There were no differences in correction rates per month for mLDFA (0.54±0.34 vs. 0.51±0.29 degrees, P =0.738) or MPTA (0.31±0.26 vs. 0.50±0.59 degrees, P =0.453) between MHE and idiopathic groups. For 11 extremities in the MHE group with open physes at hardware removal, they experienced a mean recurrence of HKA of 4.0±3.4 degrees at 19-month follow-up.

CONCLUSION

Hemiepiphysiodesis corrects lower extremity malalignment in patients with MHE at a similar rate compared with an idiopathic coronal plane deformity population. Rebound deformity of 4 degrees at 19 months after hardware removal in patients with remaining open growth plates should make surgeons conscious of the remaining growth potential when planning deformity correction.

LEVEL OF EVIDENCE

Level III.

Novel Surface Topographic Assessment of Lung Volume and Pulmonary Function Tests in Idiopathic Scoliosis: A Preliminary Study

OBJECTIVE

Severe spinal deformity results in restrictive pulmonary disease from thoracic distortions and lung-volume limitations. Though spirometry and body plethysmography are widely accepted tests for pulmonary function tests (PFTs), they are time-consuming and require patient compliance. This study investigates whether surface topographic [surface topography (ST)] measurements of body volume difference (BVD) and torso volume difference between maximum inhale and exhale correlate to values determined on PFTs.

METHODS

This study included patients with idiopathic scoliosis and thoracic/thoracolumbar curves ≥40 degrees. Patients received ST scans, clinical examinations, and EOS biplanar radiographs on the same day. PFTs were performed within 3 months of ST/radiographic analysis. Univariate linear regression analysis was used to examine relationships between BVD, PFT values, and mean curves.

RESULTS

Sixteen patients (14.6 ± 2.2 y, 69% females) with idiopathic scoliosis and mean thoracic/thoracolumbar curves of 62 degrees ± 15˚ degrees (45 degrees to 93 degrees) were assessed. BVD displayed statistically high-positive positive correlations with forced vital capacity (R= 0.863, P< 0.0001), forced expiratory volume in 1 second (R= 0.870, P< 0.001), vital capacity (R= 0.802, P< 0.0001), and TLC (R= 0.831, P< 0.0001. Torso volume difference showed similarly high positive correlations to forced vital capacity, forced expiratory volume in 1 second, vital capacity, and TLC, but not residual volume. No correlations emerged between the mean thoracic/thoracolumbar curve and BVD or PFT values.

CONCLUSION

This study strongly endorses further investigation into ST scanning as an alternative to traditional PFTs for assessing pulmonary volumes. The noncontact and noninvasive nature of ST scanning presents a valuable alternative method for analyzing thoracic volume, particularly beneficial for patients unable to cooperate with standard PFTs.

LEVEL OF EVIDENCE

Level II-prognostic.

Incidence of Nerve Palsies During Pavlik Harness Treatment for Developmental Dysplasia of the Hip: A Retrospective Cohort Study

BACKGROUND

The Pavlik harness has been used for approximately a century to treat developmental dysplasia of the hip (DDH). Femoral nerve palsy is a documented complication of Pavlik harness use, with an incidence ranging from 2.5% to 11.2%. Rare reports of brachial plexus palsy have also been documented. The primary purpose of the current study was to evaluate the incidence of various nerve palsies in patients undergoing Pavlik harness treatment for DDH. Secondary aims were to identify patient demographic or hip characteristics associated with nerve palsy.

METHODS

We performed a retrospective review of patients diagnosed with DDH and treated with a Pavlik harness from February 1, 2016, to April 1, 2023, at a single tertiary care orthopaedic hospital. Hip laterality, use of a subsequent rigid abduction orthosis, birth order, breech positioning, weight, and family history were collected. The median (and interquartile range [IQR]) or mean (and standard deviation [SD]) were reported for all continuous variables. Independent 2-sample t tests and Mann-Whitney U tests were conducted to identify associations between the variables collected at the initiation of Pavlik harness treatment and the occurrence of nerve palsy.

RESULTS

Three hundred and fifty-one patients (547 hips) were included. Twenty-two cases of femoral nerve palsy (4% of all treated hips), 1 case of inferior gluteal nerve palsy (0.18%), and 2 cases of brachial plexus palsy (0.37%) were diagnosed. Patients with nerve palsy had more severe DDH as measured by the Graf classification (p < 0.001) and more severe DDH as measured on physical examination via the Barlow and Ortolani maneuvers (p = 0.003).

CONCLUSIONS

Nerve palsies were associated with more severe DDH at the initiation of Pavlik harness use. Upper and lower-extremity neurological status should be scrutinized at initiation and throughout treatment to assess for nerve palsies. The potential for femoral, gluteal, and brachial plexus palsies should be included in the discussion of risks at the beginning of treatment. Families may be reassured that nerve palsies associated with Pavlik harness can be expected to resolve with a short break from treatment.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The global impact of the COVID-19 pandemic on pediatric spinal care: A multi-centric study

Background

The COVID-19 pandemic has affected healthcare worldwide since December 2019. We aimed to identify the effect of the COVID-19 pandemic on outpatient clinic and surgical volumes and peri-operative complications for pediatric spinal deformities patients.

Methods

In this multi-center retrospective study, outpatient visits (in-person and virtual care) and pediatric spine surgeries volumes in four high-volume pediatric spine centers were compared between March and December 2019 and the same period in 2020. Peri-operative complications were collected and compared in the same periods. Descriptive statistics were calculated, and comparative analyses were performed.

Results

During the 2020 study period, the outpatient visit (in-person and virtual care) volume decreased during local lockdown periods by 71% for new patients (p < 0.001) and 53% for returning patients (p = 0.03). Overall, for 2020, there was a 20% reduction in new patients (p = 0.001) and 21% decrease in returning patients (p < 0.001). During the pandemic, there was also 20% less overall surgical volume of adolescent idiopathic scoliosis (AIS) patients undergoing primary posterior spinal fusion, with a 70% reduction during lockdown times (p < 0.001). Complication rate and profile were similar between periods.

Conclusion

There was a significant decrease in outpatient pediatric spine outpatient visits, particularly new patients, which may increase the proportion of pediatric patients with spinal deformities that present late, meeting surgical indication. This, in combination with the reduction in surgical volume of AIS over the first year of the pandemic, could result in an extended waitlist for surgeries during years to come. Complication rate was similar for both periods, suggesting it is safe to continue elective pediatric spine surgery even in a time of a pandemic.

Level of evidence

level IV.

Changes in height, weight, and body mass index after posterior spinal fusion in juvenile and adolescent idiopathic scoliosis

Purpose

Posterior spinal fusion for idiopathic scoliosis is known to increase spinal height, but the impacts on weight and resulting body mass index are unknown. This study assesses body mass index, weight, and height percentile changes over time after posterior spinal fusion for idiopathic scoliosis.

Methods

Body mass index, weight, and height age- and sex-adjusted percentiles for patients with idiopathic scoliosis undergoing posterior spinal fusion between January 2016 and August 2022 were calculated based on growth charts from the Centers for Disease Control for Disease Control and compared to preoperative values at 2 weeks, 3 months, 6 months, 1 year, and 2 years. The data were analyzed for normality with a Shapiro-Wilk test, and percentiles were compared with the Wilcoxon signed-rank tests.

Results

On average, 12.1 ± 2.3 levels were fused in 269 patients 14.4 ± 1.9 years, and percentiles for body mass index, weight, and height preoperatively were 55.5 ± 29.4%, 57.5 ± 28.9%, and 54.6 ± 30.4%, respectively. Body mass index and weight percentiles decreased at 2 weeks (-10.7%, p < 0.001; -4.6%, p < 0.001, respectively) and 3 months (-6.9%, p < 0.001; -3.2%, p < 0.001, respectively) postoperatively. Postoperative weight loss at 2 weeks averaged 2.25 ± 3.09% of body weight (0.98 ± 4.5 kg), normalizing by 3 months. Body mass index percentile normalized at 1 year, but height percentile was increased at 2 weeks (2.42 ± 1.72 cm, p < 0.001) and through 2 years.

Conclusion

Despite initial height increase due to deformity correction, acute postoperative weight and body mass index percentile decreases postoperatively normalize by 1-year body mass index percentile. Physicians may benefit from utilizing this information when discussing the postoperative course of posterior spinal fusion with idiopathic scoliosis.

Level of evidence

4, Retrospective Case Series.

High Rates of Successful Return to Competitive Athletics After Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis Regardless of Distal Fusion Level: A Prospective Cohort Study

STUDY DESIGN

Prospective cohort.

OBJECTIVE

To determine if distal spinal fusion level is associated with postoperative sport participation after posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

The concept of "saving a level" during PSF for AIS refers to minimizing the distal extent of lumbar fusion to theoretically allow for increased postoperative spinal mobility and a more predictable return to athletic activity, as well as minimizing the risk of degenerative disc disease. There are few prospective studies evaluating the correlation between distal fusion level and timing of return to sports.

MATERIALS AND METHODS

Adolescent patients undergoing PSF for AIS between 2009 and 2019 were approached at their presurgical visit to participate in this prospective study. Participants were followed for a minimum of 2 years after surgery. Sports participation (classified by sport type and level of competitiveness) and radiographic data were collected at the initial visit. At each postoperative visit, it was noted whether patients returned to the same sport type and level of competitiveness.

RESULTS

After an a priori power calculation was performed, a total of 106 participants were included in the analysis with a mean age of 14 ± 2 years. Distal fusion levels ranged from T11 to L4. There was no significant association between distal fusion level and return to the same level of sports participation ( P = 0.192). Of the participants, 93% returned to sports with no significant differences by distal fusion level ( P = 0.081). Distal fusion level demonstrated no difference in return to preoperative sport ( P = 0.486) or return to the same type of sport ( P = 0.247).

CONCLUSIONS

This study found no association between distal fusion level and postoperative sports participation. Even though many patients may elect to change sports, nearly all patients returned to sports, and the majority of patients returned to the same level of sports competition or higher after PSF for AIS.

Variability in evaluation and treatment of tibial tubercle fractures among pediatric orthopedic surgeons

The purpose of this study was to determine the variability in clinical management of tibial tubercle fractures among a group of pediatric orthopedic surgeons. Nine fellowship-trained academic pediatric orthopedic surgeons reviewed 51 anteroposterior and lateral knee radiographs with associated case age. Respondents were asked to describe each fracture using the Ogden classification (type 1-5 with A/B modifiers), desired radiographic workup, operative vs. nonoperative treatment strategy and plans for post-treatment follow-up. Fair agreement was reached when classifying the fracture type using the Ogden classification (k = 0.39; P < 0.001). Overall, surgeons had a moderate agreement on whether to treat the fractures operatively vs. nonoperatively (k = 0.51; P < 0.001). Nonoperative management was selected for 80.4% (45/56) of type 1A fractures. Respondents selected operative treatment for 75% (30/40) of type 1B, 58.3% (14/24) of type 2A, 97.4% (74/76) of type 2B, 90.7% (39/43) of type 3A, 96.3% (79/82) of type 3B, 71.9% (87/121) of type 4 and 94.1% (16/17) of type 5 fractures. Regarding operative treatment, fair/slight agreement was reached when selecting the specifics of operative treatment including surgical fixation technique (k = 0.25; P < 0.001), screw type (k = 0.26; P < 0.001), screw size (k = 0.08; P < 0.001), use of washers (k = 0.21; P < 0.001) and performing a prophylactic anterior compartment fasciotomy (k = 0.20; P < 0.001). Furthermore, surgeons had fair/moderate agreement regarding the specifics of nonoperative treatment including degree of knee extension during immobilization (k = 0.46; P < 0.001), length of immobilization (k = 0.34; P < 0.001), post-treatment weight bearing status (k = 0.30; P < 0.001) and post-treatment rehabilitation (k = 0.34; P < 0.001). Significant variability exists between surgeons when evaluating and treating pediatric tibial tubercle fractures.

Rapidly acquired valgus deformity of the knee after osteochondroma resection in multiple hereditary exostoses pediatric patients: A report of two cases

Patients with multiple hereditary exostoses (MHE) often develop leg length discrepancies and limb alignment deformity around the knee as part of the natural course of the disease. Limb alignment deformity occurring post-resection of an osteochondroma has been described in one case report and only pertaining to the proximal medial tibia location. Here we describe the case of 2 patients with MHE, a 7-year-old female who underwent resection of distal femur and proximal tibia osteochondromas and a 9-year-old female who had a distal femur osteochondroma resected. Both patients developed rapidly progressive valgus knee deformity requiring surgical intervention. Excision of osteochondromas near the physis of a skeletally immature patient can cause overgrowth from the involved side of the growth plate resulting in a rapidly progressing unilateral coronal plane deformity. Surgeons should be aware of this potential complication and closely follow growing patients with serial alignment radiographs and counsel the family regarding the potential of acquired limb deformity and subsequent surgeries.

Biomechanical Comparison of Suture-External Button Fixation vs Internal Suspension Fixation for Tendon Transfers of the Feet

BACKGROUND

Fixation of tendon transfers in pediatric feet typically involves passing a suture that is secured to a tendon, through an intraosseous tunnel, and tying it over an external button on the plantar foot, with appropriate tension. After adequate time is allowed for bone-tendon healing, the suture and button are removed. This construct can be complicated by suture breakage with loss of fixation, and/or skin ulceration under the button. Internal suspension systems of tendons and ligaments in adults have demonstrated excellent fixation strength and minimal intraosseous tunnel displacement, with no risk of skin ulceration and no need for suture and button removal. This study compared the biomechanical properties of the suture-external button and internal suspension fixation techniques in cadavers. The primary outcome and secondary outcomes were displacement of suture-fixation construct during dynamic loading, and static loading, respectively.

METHODS

Nine adult cadaver feet were obtained. Both the external button and internal suspension techniques were tested once in each cadaver, in random order. Relative displacement of the fixation construct within the bone tunnel was recorded with video capture during dynamic and static loading. A custom Matlab script processed video and materials testing data. Static and cyclic displacements were analyzed between fixation groups using a paired t test (alpha value =0.05).

RESULTS

Internal suspension fixation had significantly less mean displacement of the tendon within the bone tunnel than the external button technique during dynamic (0.3 mm internal suspension system, 0.7 mm external button, P = .0115) and static loading (0.4 mm internal suspension system, 2.2 mm external button, P = .0019).

CONCLUSIONS

Internal suspension systems may provide superior fixation compared to the traditional external button for tendon transfers, with the added benefit of avoiding the risk of skin ulceration and the need for suture and button removal.

CLINICAL RELEVANCE

It appears internal suspension method of tendon transfer fixation would be an acceptable alternative to traditional methods of fixation with an external button.

Reliability of the Modified Clavien-Dindo-Sink Complication Classification System in Pediatric Orthopaedic Surgery

Background

There is no standardized complication classification system that has been evaluated for use in pediatric or general orthopaedic surgery. Instead, subjective terms such as major and minor are commonly used. The Clavien-Dindo-Sink complication classification system has demonstrated high interrater and intrarater reliability for hip-preservation surgery and has increasingly been used within other orthopaedic subspecialties. This classification system is based on the magnitude of treatment required and the potential for each complication to result in long-term morbidity. The purpose of the current study was to modify the Clavien-Dindo-Sink system for application to all orthopaedic procedures (including those involving the spine and the upper and lower extremity) and to determine interrater and intrarater reliability of this modified system in pediatric orthopaedic surgery cases.

Methods

The Clavien-Dindo-Sink complication classification system was modified for use with general orthopaedic procedures. Forty-five pediatric orthopaedic surgical scenarios were presented to 7 local fellowship-trained pediatric orthopaedic surgeons at 1 center to test internal reliability, and 48 scenarios were then presented to 15 pediatric orthopaedic surgeons across the United States and Canada to test external reliability. Surgeons were trained to use the system and graded the scenarios in a random order on 2 occasions. Fleiss and Cohen kappa (κ) statistics were used to determine interrater and intrarater reliabilities, respectively.

Results

The Fleiss κ value for interrater reliability (and standard error) was 0.76 ± 0.01 (p < 0.0001) and 0.74 ± 0.01 (p < 0.0001) for the internal and external groups, respectively. For each grade, interrater reliability was good to excellent for both groups, with an overall range of 0.53 for Grade I to 1 for Grade V. The Cohen κ value for intrarater reliability was excellent for both groups, ranging from 0.83 (95% confidence interval [CI], 0.71 to 0.95) to 0.98 (95% CI, 0.94 to 1.00) for the internal test group and from 0.83 (95% CI, 0.73 to 0.93) to 0.99 (95% CI, 0.97 to 1.00) for the external test group.

Conclusions

The modified Clavien-Dindo-Sink classification system has good interrater and excellent intrarater reliability for the evaluation of complications following pediatric orthopaedic upper extremity, lower extremity, and spine surgery. Adoption of this reproducible, reliable system as a standard of reporting complications in pediatric orthopaedic surgery, and other orthopaedic subspecialties, could be a valuable tool for improving surgical practices and patient outcomes.

Percutaneous Epiphysiodesis Using Transphyseal Screws: a Case Series Demonstrating High Efficacy

BACKGROUND

Percutaneous epiphysiodesis using transphyseal screws (PETS) has been associated with implant failure, implant prominence, angular deformities, and delayed growth inhibition.

QUESTIONS/PURPOSES

The aim of this study was to assess the complication rate and efficacy (defined as actual growth inhibition divided by expected growth inhibition) of PETS and to identify factors associated with improved efficacy.

METHODS

Patients who underwent distal femoral and/or proximal tibial PETS between January 2007 and June 2014 were identified. Complications, efficacy, and final limb-length discrepancy (LLD) were calculated using multipliers and inhibition rates based on previous growth. Associations between efficacy and screw insertion angle (SIA), body mass index, and number of threads crossing the physis were calculated.

RESULTS

Eight-two patients (126 treated physes) were included. The mean pre-operative LLD was 27.7 mm (SD = 7.5). Following epiphysiodesis, 15 had temporary pain (18%), five had temporary effusion (6.1%), four had broken implants (4.9%), four developed mild angulation (4.9%), and three had failed epiphysiodesis requiring revision (3.7%). Thirty-one underwent screw removal (n = 31, 38%). Mean LLD at maturity was 17.3 mm (SD = 5.8 mm). Mean efficacy at the distal femur was 97% (SD = 46%), at the proximal tibia was 108% (SD = 66%) and was 103% (SD = 57%) overall. Increased screw threads across the lateral proximal tibial physis (Spearman's correlation coefficient = 0.67; 95% CI = 0.40-0.94) and higher BMI (Spearman's correlation coefficient = 0.55; 95% CI = 0.34-0.77) were positively associated with increased efficacy.

CONCLUSIONS

The efficacy of PETS may be more favorable than previously reported. Only 3.7% had serious complications requiring revision epiphysiodesis, lower than previous reports. Attention to sufficient screw threads across the physis may be important in optimizing PETS results.

Airport metal detector activation is rare after posterior spinal fusion in children with scoliosis

PURPOSE

Since the September 11, 2001 terrorist attacks on the World Trade Center in New York City, travel security has become an ever-increasing priority in the United States. Frequent parent and patient inquiry and recent literature reports have generated interest in the impact of heightened security measures on patients with orthopaedic implants, and have indicated increasing rates of metal detector triggering. There are no reports to date, however, evaluating children and adolescents who have undergone posterior spinal fusion for scoliosis, so responses to patient and parent inquiries are not data-driven. The purpose of this study is to determine the frequency of airport metal detector triggering by patients who have had posterior-only spinal fusion and to characterise any potential predictors of metal detector activation.

METHODS

A cross-sectional study was performed by interviewing 90 patients who underwent posterior-only spinal fusion for a diagnosis of juvenile or adolescent idiopathic scoliosis and have travelled by air in the past year. Demographic, clinical and surgical instrumentation data were collected and evaluated, along with patients' reports of airport metal detector triggering and subsequent screening procedures.

RESULTS

Five patients with stainless steel instrumentation (5.6 % of the cohort) triggered an airport walkthrough metal detector, and an additional five patients who did not trigger an airport detector triggered a handheld detector at a different venue. All patients who triggered an airport metal detector had stainless steel instrumentation implanted prior to 2008, and no patient with titanium instrumentation triggered any detector in any venue. All trigger events required subsequent screening procedures, even when an implant card was presented.

CONCLUSIONS

In this cohort of children and adolescents with posterior spinal instrumentation, airport walkthrough metal detector triggering was a rare event. Therefore, we advise patients and families with planned posterior scoliosis fusions using titanium instrumentation that airport detection risk is essentially non-existent, and only rare for those with planned stainless steel instrumentation. We no longer issue implant cards postoperatively, as these did not prevent further screening procedures in this cohort.

LEVEL OF EVIDENCE

Prognostic level 2.

STUDY DESIGN

cross-sectional.

Multimodal pain management after spinal surgery for adolescent idiopathic scoliosis

Corrective surgery for scoliosis is an extensive procedure with well-known problems of postoperative pain control. Additional problems with nausea, vomiting, ileus, and sedation can result in delayed mobilization and a prolonged inpatient hospital stay. At our institution, a multimodal approach to pain management has been used to successfully address these issues. The use of intravenous acetaminophen has been a helpful adjunct to our armamentarium of pain medication in this patient population. We present an illustrative case of our use of multimodal analgesia beginning intraoperatively and continuing during the acute inpatient postoperative period.

Allograft bone in spinal fusion for adolescent idiopathic scoliosis

OBJECTIVE

The purpose of this long-term study was to determine the efficacy of allograft bone for spinal fusion for adolescent idiopathic scoliosis. Prior studies comparing allograft and autograft have been short term.

METHODS

This multicenter retrospective study was carried out on 111 patients with 132 total curves fused for adolescent idiopathic scoliosis. Minimum follow-up was 5 years (average 72 months). A variety of segmental instrumentation was used, with most being dual-rod, multiple-hook constructs.

RESULTS

Average preoperative curve was 59 degrees with immediate correction to 29 degrees (51%) and final follow-up of 32.24 degrees (45.4%). Average loss of correction was 3.5 degrees (5.9%). There were three pseudarthroses, one infection, and no rod breakage.

CONCLUSION

Pseudarthrosis rate of 2.7% and loss of correction of 5.9% are comparable with or better than those in previous reports using autogenous bone graft and either segmental or nonsegmental instrumentation.

Relationships among musculoskeletal impairments and functional health status in ambulatory cerebral palsy

Orthopedic surgery for patients with cerebral palsy addresses motion impairments, assuming that this will improve motor function. This study evaluates the relationships among clinical impairment measures with standardized assessments of function and disability as an initial step in testing this assumption. A total of 129 ambulatory children and adolescents across six institutions participated in a prospective evaluation that consisted of passive motion and spasticity examination of the lower extremities, three-dimensional gait temporal-spatial and kinematic analysis, and administration of the Gross Motor Function Measure (GMFM) and the Pediatric Outcomes Data Collection Instrument (PODCI). The analysis found that isolated impairment measures of motion and spasticity were only weakly related to motor function in cerebral palsy and even when averaged across multiple joints yielded no more than a fair correlation with functional scores, nor did a combination of impairments emerge that could predict substantial variance in motor function. These findings suggest that caution should be exercised when anticipating functional change through the treatment of isolated impairment and that addressing multiple impairments may be needed to produce appreciable effects.

Ankle and knee coupling in patients with spastic diplegia: effects of gastrocnemius-soleus lengthening

BACKGROUND

Empirical observations of subjects with an equinus gait have suggested that there is coupled motion between the ankle and knee such that, during single-limb stance, the ankle moves into equinus as the knee extends. Since the gastrocnemius-soleus muscle-tendon unit spans both joints, we hypothesized that this muscle-tendon unit may be responsible for the coupling and that lengthening of the gastrocnemius-soleus muscle alone would result in greater ankle dorsiflexion as well as greater knee extension in single-limb stance, effectively uncoupling these joints. The concept that gastrocnemius-soleus lengthening may promote knee extension is counter to the popular notion that crouch gait may result if the hamstrings are not lengthened concomitantly.

METHODS

A retrospective review identified thirty-four subjects with specific kinematic characteristics of equinus gait, and their gait was compared with that of normal children. Of the thirty-four subjects, eleven (twenty-two limbs) subsequently underwent isolated midcalf lengthening of the gastrocnemius and soleus muscles with use of a recession technique. Gait analysis including joint kinematics and joint kinetics, electromyography, and physical examination were performed to test the hypothesis.

RESULTS

We found that, unlike the normal subjects, the patients with an equinus gait pattern had a positive correlation (r = 0.7) between ankle and knee motion during single-limb stance. As hypothesized, ankle plantar flexion occurred while the knee moved into extension during single-limb stance. Calculations of the lengths of the gastrocnemius-soleus muscle-tendon units showed them to be short throughout the gait cycle (p < 0.0001). After gastrocnemius-soleus recession, peak ankle dorsiflexion (p < 0.001) and peak ankle power (p < 0.001) shifted to occur later in stance than they did in the preoperative gait cycle. Furthermore, the magnitude of peak power increased (p < 0.001) in late stance despite the added length of the gastrocnemius-soleus muscle-tendon unit. The electromyographic amplitude of the gastrocnemius-soleus was reduced during loading (p < 0.02), and this finding, together with the kinetic changes, suggested that muscle tension was reduced. Changes at the knee were less pronounced but included greater knee extension at foot contact (p < 0.01). No increase in the knee flexion angle or extension moment occurred in midstance after the surgery.

CONCLUSIONS

Patients with an equinus gait pattern function with a shortened gastrocnemius-soleus muscle-tendon unit, and this results in coupled motion between the ankle and knee during single-limb stance. Lengthening, with use of a recession technique, shifted ankle power generation and dorsiflexion to a later time in stance with no tendency to increase midstance knee flexion. Knee extension did increase at foot contact, but excessive midstance knee flexion persisted and was likely due to concomitant contracture of the hamstrings.

Posterior-only unit rod instrumentation and fusion for neuromuscular scoliosis

STUDY DESIGN

A retrospective study to determine the efficacy of posterior-only unit rod instrumentation and fusion in a skeletally immature neuromuscular scoliosis population.

OBJECTIVE

To determine whether the posterior-only approach to this population adequately addresses the concerns of correction of scoliosis and pelvic obliquity, maintenance of that correction over time, and the incidence of crankshaft phenomenon.

SUMMARY OF BACKGROUND DATA

Controversy exists regarding the need for anterior release to improve curve flexibility and the need to obtain an anterior arthrodesis in those skeletally immature patients at risk for crankshafting with continued anterior growth.

METHODS

From 1992 through 1997, 28 consecutive skeletally immature patients with neuromuscular scoliosis underwent posterior-only unit rod instrumentation and fusion for the treatment of progressive, symptomatic spinal deformities. Preoperative, immediate postoperative, and final follow-up radiographs were analyzed with respect to scoliosis and pelvic obliquity correction, maintenance of that correction over time, and the development of the crankshaft phenomenon as evidenced by loss of correction and/or increased rib-vertebral angle difference. The average age of the patients was 12.8 years and the average follow-up was 58 months with a minimum of 2 years.

RESULTS

Twenty-six patients were available for final follow-up. The initial Cobb angle correction averaged 66%, with 75% of the pelvic obliquity corrected. These corrections were maintained over time. Before surgery 27 of 28 patients were Risser 0, 1, or 2. The triradiate cartilage was open in nine patients, and five patients were < or =10 years of age. At the final follow-up 22 of the 26 patients were Risser 5 and 4 were Risser 4. There was one patient with increased rib-vertebral angle difference over the length of follow-up, with no loss of frontal or sagittal plane alignment.

CONCLUSIONS

These results indicate that even in the very young neuromuscular patient, acceptable amounts of curve correction can be achieved and maintained with posterior-only unit rod instrumentation and fusion. The biomechanical stiffness of this construct seemed to be able to prevent the crankshaft phenomenon in the majority of those patients at risk.

Posterior spinal instrumentation and fusion of a neuromuscular scoliosis in a patient with autosomal dominant osteopetrosis

STUDY DESIGN

A case report of a patient with autosomal dominant osteopetrosis and neuromuscular scoliosis who required surgical instrumentation and fusion of her spine.

OBJECTIVE

To illustrate the surgical technique and long-term outcome in this rare form of spinal deformity.

SUMMARY OF BACKGROUND DATA

Osteopetrosis is a group of rare skeletal dysplasias characterized clinically by skeletal osteosclerosis that is classically described in appearance as "marble bone." Despite the ubiquitous involvement of the vertebra, clinical manifestations of spinal involvement are uncommon. We present the case of an osteopetrotic patient with neuromuscular scoliosis who required surgical correction of her progressive deformity. There are no prior reports in the literature concerning operative or nonoperative management of scoliosis in this patient population.

METHODS

The surgical technique utilized as well as the patient's response to surgical management of her scoliosis is presented with 5 year follow-up.

RESULTS

The patient underwent a successful T4 to L1 posterior spine fusion and instrumentation using Luque rods, sublaminar wires and allograft bone augmentation. At 5 years following her index procedure, she is clinically and radiographically fused.

CONCLUSION

Patients with osteopetrosis present unique surgical challenges during surgical correction of spinal deformities. The use of segmental sublaminar wires with 1/4-inch rods and crosslinks afforded stable fixation despite poor bone quality. Allograft bone combined with postoperative bracing resulted in a well-maintained correction and a solid fusion. Five year follow-up and continued radiographic evidence of stable fusion indicate that the presented approach can lead to a successful outcome in the osteopetrotic patient population.

Asymmetric hip deformity and subluxation in cerebral palsy: an analysis of surgical treatment

Thirty-seven cerebral palsy patients were followed with measurements of the migration index (MI), infrapelvic obliquity, and suprapelvic obliquity over a mean period of 73 months to evaluate the development of the windblown deformity. The infrapelvic asymmetry was apparent before the suprapelvic obliquity; however, 65% eventually had both. The final pattern of infrapelvic obliquity and the most subluxed hip could not be predicted from initial radiographs or from the pattern of scoliosis. Hip subluxation strongly correlated with the degree of femoral adduction and weakly with the magnitude of suprapelvic obliquity. The suprapelvic obliquity and scoliosis increased over time and influenced the final windblown appearance. Soft-tissue surgeries did not have a significant effect on the final MI. Severe abduction deformities generally followed ipsilateral adductor releases. Finally, despite improvement in the MI of the initially more subluxed hip, 33% of patients still had one hip with a MI >50%.

Bilateral femoral neck fractures secondary to hypocalcemic seizures in a skeletally immature patient

We report the case of an 11-year-old, skeletally immature boy who sustained bilateral femoral neck fractures during seizure activity. These fractures were due to hypocalcemia. Although this condition is a rare complication of seizures, its early recognition and treatment are essential to minimize complications associated with the delayed treatment of intracapsular hip fractures.

Familial synspondylism: progressive scoliosis and multiple hernias in a kinship

A new genetic syndrome is reported of congenital lordoscoliosis due to lumbar segmentation defects and incomplete formation of lumbar vertebrae. The defect arose as a spontaneous mutation and was transmitted in an autosomal dominant fashion. The kindred included a mother and her three offspring. These affected individuals had several dysmorphic features including cavus feet and micrognathia. In addition the syndrome was associated with multiple hernias including inguinal, ventral, and diaphragmatic. These associated problems led to the early death of the first child at age 7 months. The lumbar scoliosis was already evident by that time. The progressive nature of the scoliosis was documented, especially in one child who was lost to follow-up and who was initially seen with a severe spinal deformity. Surgical management was required in members of the kindred, but because of differences in age and severity at the time of surgery, the techniques varied.

Allograft bone use during instrumentation and fusion in the treatment of adolescent idiopathic scoliosis

STUDY DESIGN

In a retrospective study, 25 patients undergoing posterior spine fusion with allograft bone and Cotrel-Dubousset Instrumentation were assessed regarding the efficacy of allograft bone use.

OBJECTIVES

To determine if allograft bone use had deleterious effects regarding fusion rates and maintenance of deformity correction.

SUMMARY OF BACKGROUND DATA

Previous studies using allograft bone in adult lumbar spine fusion models have consistently shown poor fusion rates. Studies in the pediatric population have been more favorable but in idiopathic cases have used cast or brace immobilization with Harrington instrumentation.

METHODS

Twenty-five skeletally immature patients with is average age of 14 +/- 4 years and an average follow-up of 4 +/- 2 years (minimum of 3 years) were evaluated with anteroposterior, lateral, and oblique radiographs to assess the fusion mass.

RESULTS

Preoperative curves averaged 55.5 degrees and immediate correction averaged 58% with an average postoperative curve of 23.2 degrees. Loss of correction at final follow-up was 3.7 degrees. No pseudarthroses were identified clinically or radiographically.

CONCLUSIONS

Allograft bone use in the pediatric patient with idiopathic scoliosis undergoing rigid segmental instrumentation dependably results in fusion with good maintenance of correction.

External fixation of pediatric femoral fractures

Fifteen pediatric femoral fractures in 14 patients were treated with external fixation using the EBI Orthofix unilateral external fixator. The average patient age was 8.5 years (range, 3-13 years). There were 7 children with multiple injuries and 7 with isolated fractures. The average duration in the fixator was 63 days; average followup was 34 months. All 15 fractures healed without additional operative intervention. Average angulation at the fracture site was 4.4 degrees in the anteroposterior plane (range, 0 degrees-10 degrees) and 4.6 degrees in the lateral plane (range, 0 degrees-11 degrees). There were 5 pin tract infections, all of which resolved with systemic antibiotics. There was 1 case of refracture in a boy with muscular dystrophy. Ten patients had clinically equal leg lengths, 3 patients had < 1 cm of inequality, and 1 patient had a 1.5 cm discrepancy. External fixation is a well-proven technique for managing pediatric femoral fractures in the child with multiple injuries. It is also an effective means of treating isolated femoral fractures in the pediatric population.

Ability of visual tests to predict underlying cervical neoplasia. Colposcopy and speculoscopy

OBJECTIVE

To describe the attributes of colposcopy and a low-power, magnified examination that utilizes chemiluminescent illumination (speculoscopy) in the visualization of cervical epithelium in a predefined, high-risk population and to compare how the two tests predict cervical histology.

STUDY DESIGN

During this multicenter, prospective study, 395 women who were referred to our colposcopy clinic underwent a repeat cervical smear and speculoscopy followed immediately by colposcopy. Abnormal colposcopic lesions were biopsied and endocervical curettage performed when indicated. Histologic diagnoses were compared with cytology, speculoscopy and colposcopy results.

RESULTS

Colposcopy was more sensitive than speculoscopy in the detection of cervical neoplasia (97% vs. 82%) (P < .001) and was superior in visualizing focal lesions and vascular patterns. An antecedent acetowhite abnormality detected during speculoscopy was highly predictive of subsequent abnormal colposcopy (97% positive predictive value). The "overall" rate of acetowhite lesions during speculoscopy was nearly half the rate during colposcopy (P < .001).

CONCLUSION

Colposcopy is better suited than speculoscopy to the follow-up of patients with abnormal cervical cytology because it facilitates lesion grading and assists in directing biopsies. Speculoscopy is best utilized as a dichotomous screening test based on the presence or absence of at least one well-demarcated acetowhite lesion and may be more suitable than colposcopy as an adjunct to cervical cancer screening due to its lower overcall rate. The biophysical properties of blue-white chemiluminescent light as it relates to the diagnosis of cervical neoplasia are discussed.

Clinical evaluation of crossed-pin versus lateral-pin fixation in displaced supracondylar humerus fractures

The radiographs and patient charts of 47 children treated with closed reduction and percutaneous pin fixation of displaced supracondylar humerus fractures were reviewed. Twenty-seven fractures were fixed with crossed medial and lateral pins. Twenty fractures were treated with two parallel laterally placed pins. Baumann's angle on the anteroposterior elbow film and the humerocapitellar angle on the lateral elbow film were independently measured by the three authors on initial postoperative films and on films taken at the time of pin removal. No statistically significant differences regarding maintenance of reduction were found when comparing the two fixation groups. There were two complications in the medial pin group (one cubitus varus and one ulnar nerve injury) and none in the lateral-pin group. We conclude that crossed-pin fixation offers no clinically significant advantage over two laterally placed pins in the treatment of supracondylar humerus fractures.

Direct spinal stimulation for intraoperative monitoring during scoliosis surgery

Intraoperative electrophysiological monitoring of the spinal cord has traditionally been done by recording somatosensory evoked potentials (SEP). There is a risk that SEPs can be unaltered when significant injury to the anterior spinal cord has occurred. The purpose of this report is to describe a simple technique for intraoperative spinal cord stimulation which monitors descending pathways in the anterior spinal cord. Stimulation occurs through needle electrodes inserted into spinous processes in the rostral surgical wound, and recordings are made from electrodes in the popliteal spaces. We report our experience in monitoring spinal instrumentation in 45 patients with idiopathic scoliosis and 20 with some form of neurological disease causing scoliosis. The neurogenic motor evoked potentials (NMEP) are stable and easily recorded from the popliteal spaces in the majority of patients. We describe the case of 1 patient with Friedreich's ataxia in whom no SEPs could be recorded, but NMEPs were used successfully for monitoring. We have fond that combining traditional SEP monitoring with NMEP recording provides a safe and effective method to monitor the spinal cord during surgical procedures where it is at risk.

Use of speculoscopy in the evaluation of women with atypical Papanicolaou smears. Improved cost effectiveness by selective colposcopy

Since up to 45% of patients with atypical Papanicolaou smears have been shown to have significant pathology, women with persistent atypia are usually referred for colposcopy. This study evaluated the use of a new adjunctive screening test, speculoscopy, in selecting women with atypical Papanicolaou smears who would most benefit from referral for colposcopy. Both screening and referral patients were evaluated with the Papanicolaou smear, speculoscopy and colposcopy at 10 study centers. Biopsies were obtained from most women with positive colposcopy. The results in patients with atypical smears were used to perform a cost-benefit analysis of each of three management protocols. Using the results of speculoscopy to select women with atypical Papanicolaou smears for colposcopy provided a cost-effective alternative to performing colposcopy either on all women or on those with persistent atypia following treatment. Even when all women undergo speculoscopy at the time of screening, this protocol provides a cost savings of up to 24% and no significant loss of diagnostic accuracy. These data suggest that speculoscopy performed at the time of initial screening can accurately select women with atypical Papanicolaou smears who require colposcopy for diagnostic biopsy in a cost-effective manner.

Comparison of single pin versus multiple pin fixation in treatment of slipped capital femoral epiphysis

From January 1982 to December 1987, 114 hips of 80 patients underwent pinning for treatment of slipped capital femoral epiphysis (SCFE). Three groups were differentiated based on the number of pins used. The average length of follow-up was 2 years 5 months. The mean time to physeal closure was 5.43 months in the single pin group, 5.54 months in the two pin group, and 6.44 months in the three or more pin group. These differences were not statistically significant. There was a statistically significant decrease in the rate of pin-related complications and reoperations in the single pin group as compared with the two pin and multiple pin groups. We conclude that central single pin fixation for treatment of SCFE dependably results in physeal closure while minimizing pin-related complications.

Correlation of the Papanicolaou smear and human papillomavirus type in women with biopsy-proven cervical squamous intraepithelial lesions

The authors correlated Papanicolaou smear diagnoses with the presence of human papillomavirus (HPV) as determined by in situ hybridization in concurrent biopsy-proven cervical squamous intraepithelial lesions (SILs) in 132 women. Infection by HPV 6 or 11 was associated with a simultaneous normal Papanicolaou smear in 4 of 29 (14%) cases. This result was significantly greater (P less than 0.05) than that found in cases of infection by an oncogenic HPV type (types 16, 31, 33, 35, and others), in which the rate of a concurrent normal Papanicolaou smear was 5 of 88 (5%). Infection by one of these oncogenic types was associated with a Papanicolaou smear diagnostic of SIL in 55 of 88 (63%) cases, whereas infection by HPV 6 or 11 was associated with a Papanicolaou smear diagnostic of SIL significantly (P less than 0.05) less frequently (6 of 29, 18%). It is concluded that, for women with SILs, the likelihood of a Papanicolaou smear diagnostic of the lesion is greater for women with HPV types of known oncogenic potential.

Congenital Chopart amputation. A functional assessment

Of 11 patients with congenital Chopart-level foot amputations, the average age was 6.75 years. Data collected from each patient included leg-length and calf-circumference measurements, range of motion at the ankle and subtalar joints, and a record of stump appearance. The patients were timed running a 50-m dash and measured in a standing broad-jump performance. Patients with congenital Chopart amputations functioned within normal limits in all of the authors' tests. No patient had a plantar flexion deformity. A slipper-style shoe filler or ankle foot orthosis with a foot plate and shoe filler was used as an easily fabricated and very functional prosthesis. The Chopart foot was found to have many advantages compared to a Symes-level amputation, including maintenance of functional length of the extremity, preservation of a broad weight-bearing surface, and an intact plantar fat pad.

Human papillomavirus detection in cervical lesions nondiagnostic for cervical intraepithelial neoplasia: correlation with Papanicolaou smear, colposcopy, and occurrence of cervical intraepithelial neoplasia

Human papillomavirus (HPV) is associated with cervical intraepithelial neoplasia (CIN) and carcinomas. The present study involved women who had an abnormal Papanicolaou smear and whose cervix contained acetowhite area(s) that lacked the histologic features of CIN. Sequences homologous to HPV DNA, determined by Southern blot hybridization analysis, were detected in 20 of 59 cervical biopsy specimens (34%) that lacked the histologic features of CIN. When compared with the group in which HPV DNA was not detected, the HPV DNA-positive group had a lower chance of having a normal Papanicolaou smear (30 versus 61%) at the time of the biopsy. There was no difference in the colposcopic findings between the HPV DNA-positive and -negative cases for the biopsy specimens that lacked the features of CIN. However, there was a difference in the rate of histologically proved CIN in the two groups. Twelve of 17 women (71%) in the HPV DNA-positive group for whom there was follow-up information had a biopsy-proved CIN lesion noted at another location in the cervix at the time of biopsy (six) or 3-12 months after the biopsy (six). This rate was significantly higher (P less than .05) than the rate (five of 25, 20%) in the HPV DNA-negative cases, most of whom had no colposcopic abnormalities and a normal Papanicolaou smear at the follow-up examination. These findings indicate that HPV DNA detection in women with cervical lesions that lack the histologic features of CIN predicts current or future CIN in such patients.

Correlation of histology and human papillomavirus DNA detection in condyloma acuminatum and condyloma-like vulvar lesions

The diagnosis of a vulvar condyloma is made when perinuclear halos are seen with nuclear atypia and binucleate forms (koilocytotic atypia). These changes are most prominent in the granular layer and are associated with the presence of human papillomavirus (HPV). However, these changes may be absent or minimal in patients with papillary vulvar lesions; this situation can thus present diagnostic difficulties. We analyzed the histologic features of 53 biopsies from 48 patients who had vulvar lesions suggestive of condylomata. Of the 26 biopsy specimens with koilocytotic atypia, 20 (77%) had sequences homologous to HPV DNA as detected by Southern blot hybridization analysis using a probe of HPV s 6/11, 16, 18, 31, 35, and 51. In cases where the histologic features were suggestive but not diagnostic of condylomata, because unequivocal koilocytotic atypia was not noted, five of 27 (19%) had detectable HPV DNA. In this latter group, we found no histologic feature to distinguish the cases that had detectable HPV DNA from those that did not. Analysis for HPV DNA by in situ hybridization in the cases that were histologically equivocal for condyloma was uniformly negative. We conclude that there is a marked decrease in the detection rate of the HPV types associated with genital tract neoplasms in vulvar lesions that lack koilocytotic atypia. Southern blot hybridization analysis was the only reliable way to distinguish the "equivocal for condyloma" cases that had HPV from those where HPV DNA was not detected.

Histologic correlates of papillomavirus infection of the vagina

Vaginal warts (condylomata) secondary to human papillomavirus (HPV) infection are most easily identified when perinuclear halos are seen with clear-cut nuclear atypia (koilocytotic atypia) in the superficial cells of the lesion. However, vaginal lesions clinically resembling condylomata may exhibit lesser degrees of nuclear atypia with findings suggestive of, but not typical for, the presence of HPV. The diagnosis and management of such lesions are unclear. We correlated histologic findings with the detection of HPV DNA sequences in 39 vaginal lesions that contained a spectrum of clinical and histologic features suggestive of, or diagnostic for, condyloma. We detected HPV DNA in 63% (N = 22) of lesions with koilocytotic atypia and in 11.7% (N = 17) of lesions that showed some histologic features suggesting condyloma but that lacked koilocytotic atypia. These findings imply that vaginal lesions lacking koilocytotic atypia are not always caused by HPV, emphasizing the need for a conservative approach when the diagnosis of vaginal condyloma is not clear-cut.

A suburethral sling procedure with polytetrafluoroethylene for the treatment of genuine stress incontinence in patients with low urethral closure pressure

One indication for suburethral sling procedures has been recurrent genuine stress incontinence after previous incontinence surgery. Patients with low urethral closure pressures (20 cm H2O or less) in association with genuine stress incontinence are at particular risk for failure of standard anti-incontinence procedures. Urodynamic evaluation was used to select 17 patients with genuine stress incontinence and low urethral closure pressures for surgical treatment with a sling procedure using polytetrafluoroethylene. The technique of the procedure, cure rate, and postoperative complications were assessed. An 85% subjective and objective cure rate was found on urodynamic testing three months postoperatively. Complications included wound seroma, urinary tract infection, and urinary retention.