Caglar Yilgor

Evaluation of acetabular development after Dega acetabuloplasty in developmental dysplasia of the hip.

The Dega acetabuloplasty is considered to be safe and effective in the treatment of hip pathologies, but the number of clinical follow-up series in the literature is not sufficient. The aim of our study was to identify the alterations in acetabular development in 35 patients (43 hips) with developmental dysplasia of the hip who were treated with Dega acetabuloplasty. This study is a retrospective review of 7 years of one surgeon’s experience with Dega acetabuloplasty performed between May 2002 and January 2010. A total of 35 patients (43 hips) were evaluated, with an average of 58 months (range 25–108 months) of follow-up. Dega acetabuloplasties that were performed for neuromuscular or other conditions and patients who had a follow-up period of less than 2 years were excluded. Open reduction was performed and femoral shortening or varus osteotomy was added whenever the surgeon considered it necessary. The preoperative mean acetabular index (AI) was 35° (range 27–53°), and the mean age of operation was 35 months (range 18–65 months). The mean AI in the early postoperative period was 20° (range 10–34°). At the last follow-up, all patients were pain-free and had unlimited physical activity with no limp, with an improvement in AI to 13° (range 5–23°). An improvement of 7° was observed in AI within the follow-up period. The maximum improvement was 17° and occurred within an 83-month period. In 42 of 43 (98%) of the hips, the AI improved; in one of 43 (2%) of the hips, it remained unchanged and in none of hips did the AI worsen over time. This study is one of the largest series in the English-language orthopedic literature to report that Dega osteotomy is effective in improving the AI and femoral coverage, and that the index further improves over the course of the follow-up period.

Global Alignment and Proportion (GAP) Score: Development and Validation of a New Method of Analyzing Spinopelvic Alignment to Predict Mechanical Complications After Adult Spinal Deformity Surgery.

Background: The restoration of normal sagittal alignment is a critical goal in adult spinal deformity surgery to achieve favorable outcomes and prevent mechanical complications. Schwab sagittal modifiers have been accepted as targets for appropriate alignment, but addressing these targets does not always prevent high mechanical complication or revision rates. This may be because the linear absolute numerical parameters do not cover the whole pelvic incidence spectrum and the distribution of lordosis, pelvic anteversion, and negative malalignment are not considered as potential causes of failure. The aim of the present study was to develop and validate a score based on pelvic-incidence-based proportional parameters to better predict mechanical complications. Methods: Two hundred and twenty-two patients (168 women and 54 men) followed for ≥2 years after posterior fusion at ≥4 levels were included in the study. The mean age (and standard deviation) was 52.2 ± 19.3 years (range, 18 to 84 years), and the mean duration of follow-up was 28.8 ± 8.2 months (range, 24 to 62 months). The global alignment and proportion (GAP) score was developed and validated in groups of patients randomly assigned to derivation (n = 148, 66.7%) and validation (n = 74, 33.3%) cohorts. GAP score parameters were relative pelvic version (the measured minus the ideal sacral slope), relative lumbar lordosis (the measured minus the ideal lumbar lordosis), lordosis distribution index (the L4-S1 lordosis divided by the L1-S1 lordosis multiplied by 100), relative spinopelvic alignment (the measured minus the ideal global tilt), and an age factor. Proximal and distal junctional kyphosis and/or failure, rod breakage, and other implant-related complications were considered mechanical complications. The predictive accuracy of the GAP score was analyzed using receiver operating characteristic (ROC) analyses. Associations between GAP categories and mechanical complications and revisions were analyzed using Cochran-Armitage tests. Results: In the validation cohort, 32 patients (43%) experienced mechanical complications and 17 (23%) underwent mechanical revision. The area under curve for the GAP score predicting mechanical complications was 0.92 (standard error [SE] = 0.034, p < 0.001, 95% [confidence interval [CI] = 0.85 to 0.98). Postoperatively, patients with a proportioned spinopelvic state according to the GAP score had a mechanical complication rate of 6% while those with a moderately or severely disproportioned spinopelvic state had rates of 47% and 95%, respectively. Conclusions: The GAP score is a new pelvic-incidence-based proportional method of analyzing the sagittal plane that predicts mechanical complications in patients undergoing surgery for adult spinal deformity. Setting surgical goals according to the GAP score may decrease the prevalence of mechanical complications.

Effects of the fusionless instrumentation on the disks and facet joints of the unfused segments: a pig model.

Background: Growing rod (GR) is a state-of-the-art procedure favored when curvatures of the spine cannot be managed nonoperatively in early-onset scoliosis. Although some postulate that multiple distractions and/or relative immobilization of the unfused segments affect the health of disk and facet joint (FJ) and cause degeneration and/or spontaneous fusion, this has not thoroughly been investigated. In this study, changes in the unfused segment after a spine-based fusionless instrumentation (SBFI) are investigated and compared with the control (CG) and instrumented fusion (IF) groups. Methods: A total of 13 piglets, 10 to 14 weeks of age, were used. SBFI and IF were performed on 7 and 3 piglets, respectively, and 3 formed the CG. In SBFI, lengthening procedures of 5 mm were applied once monthly for 3 months, and, after 4 months, all piglets were euthanized. Histologic sections of the unfused disks and FJ were analyzed, and morphometric histologic analysis was performed. Results: On the basis of the Gries criteria, unfused disk median grades were 1, 2, and 4 for control, SBFI, and IF, respectively, that revealed a statistical difference (P<0.001). Unfused FJ median grades were 1 and 2 for control and SBFI, respectively, that revealed a statistical difference (P<0.001). The mean hypertrophic zone (HZ) heights were 69.78, 84.20, and 66.14 &mgr;m; HZ chondrocyte cell widths were 19.03, 18.76, and 17.36 &mgr;m; and HZ chondrocyte cell heights were 15.01, 15.04, and 12.42 &mgr;m in the CG, SBFI, and IF groups, respectively. Statistically, for HZ heights, SBFI was different compared with CG and IF (P<0.001), and, for HZ chondrocyte cell widths and heights, IF was different compared with CG and SBFI (P<0.001). Conclusions: Morphometric analysis in this study supports the findings that SBFI preserves the growth potential of the spine. Furthermore, changes in the HZ heights show that distractive forces stimulate the apophyseal growth of the axial skeleton describing how the growth rate of the spine in GR might surpass the normal growth rate. Overall, although some degenerative changes are observed, SBFI and repeated distractions alone are not solely responsible for FJ arthrosis and disk degeneration, given that they are structurally preserved. Clinical Relevance: GR and regular lengthening procedures do not impair disk health and preserve the growth potential of the spine if it is applied with a meticulous technique.

Is expansion thoracoplasty a safe procedure for mobility and growth potential of the spine? Spontaneous fusion after multiple chest distractions in young children.

Background: Expansion thoracoplasty (ET) is claimed to be a spine-sparing procedure because of the fact that the spine is not exposed directly and intervention toward the spinal column is not performed. It is also recommended in cases of primary spine deformities without rib fusion/aplasia and when the primary problem is not in the thorax itself. The aim of this study was to report spontaneous spinal fusion after multiple thoracic distractions in patients with congenital thoracospinal deformities who have undergone ET in early childhood. Methods: In our clinic, between May 2003 and March 2010, ET treatment was started in 11 patients who had congenital spinal deformity along with thoracic asymmetry due to fused ribs. The lengthening procedures for 6 of them are still ongoing. This study includes 5 of these patients who had undergone 3-dimensional computed tomography (3D-CT) scans. Four of these patients underwent a CT scan as part of the graduation protocol and 1 was ordered a 3D-CT because a newly formed bony fusion of the ribs was observed in a lengthening procedure. Results: The mean age of the patients (4 F, 1 M) was 4.2 years (range, 2 to 8 y) at the time of the index operation. The mean number of lengthening procedures was 9.4 (range, 7 to 13). The mean follow-up period was 73 months (range, 60 to 96 mo). All 5 patients in the latest follow-up were evaluated by x-ray and 3D-CT scans of the whole spine. The CT scans confirmed spontaneous spinal fusion in the thoracic spine. Conclusions: We speculate that distraction-based, growth-friendly instrumentations are not risk-free for spinal health and motion, even when the instrumentation is not primarily on the spine. Level of Evidence: Level IV.

Fusionless instrumentation in growing spine and adjacent segment problems: an experimental study in immature pigs.

Study Design. Experimental study. Objective. To compare the effects of fusionless instrumentation (FI) and instrumented fusion (IF) on the adjacent segment in an immature pig model. Summary of Background Data. Observations reveal proximal junctional kyphosis after FI. Possible reasons are stress concentration, repeated distractive forces, and/or soft tissue damage done in the index surgery. It was speculated that FI can decrease stressors to the junctional area by preserving the spinal mobility in some manner; however, this has not been proven to date. Methods. Thirteen piglets of 10- to 14-week age were used. FI and IF were performed on 7 and 3 piglets, respectively, and 3 piglets formed the control group. Control piglets did not undergo any surgical procedures. T11–L4 instrumentation, decortication, and grafting were applied to IF piglets. In FI groups, however, L1–L2 was left uninstrumented and unfused using T11–T12 and L3–L4 levels as anchors to the growing construct. A total of 4 lengthening procedures were performed: 1 in the index operation and 3 more, once in each lengthening procedure monthly, for 3 months. Four months after the index operations, all piglets were killed and the adjacent segment motion capabilities, disc, and facets were evaluated with radiographical, magnetic resonance imaging, biomechanical, and histological analyses. Results. Comparison of proximal junctional Cobb angles of the postindex (mean: 21, range: 17–27) and presacrification (mean: 21, range: 11–31) radiographs in the FI group revealed no difference (P> 0.05). In magnetic resonance imaging, both surgical group proximal adjacent discs showed degeneration to some degree that was statistically indifferent (P = 0.903). Biomechanical evaluation revealed restriction of adjacent segment motion in all directions for both groups; however, this negative effect was significantly less in FI group (P < 0.01). Degeneration observed in histological evaluation in adjacent discs and facets of FI group was significantly lower (P = 0.00). Conclusion. In this quadruped straight spine model, in comparison with IF applications, FI is closer to normal physiology even after several lengthening procedures regarding the adjacent segment discs, facet joints, and motion, when interpreting the radiological, biomechanical, and histological results altogether. Level of Evidence: N/A

Simultaneous forequarter amputation and radical mastectomy for metastatic breast carcinoma in a male patient: a case report

Although the majority of forequarter amputations are performed for high-grade bone and soft tissue sarcomas or extensive osteomyelitis of the upper extremity, this radical operation may also be indicated for the curative treatment of recurrent breast cancer and for the palliation of locally advanced breast cancer. We report a male patient with metastatic breast adenocarcinoma who underwent simultaneous mastectomy and forequarter amputation for the management of both his primary and metastatic disease.

Global tilt and lumbar lordosis index: two parameters correlating with health-related quality of life scores—but how do they truly impact disability?

BACKGROUND CONTEXT Many radiological parameters have been reported to correlate with patients disability including sagittal vertical axis (SVA), pelvic tilt (PT), and pelvic incidence minus lumbar lordosis (PI-LL). European literature reports other parameters such as lumbar lordosis index (LLI) and the global tilt (GT). If most parameters correlate with health-related quality of life scores (HRQLs), their impact on disability remains unclear. PURPOSE This study aimed to validate these parameters by investigating their correlation with HRQLs. It also aimed to evaluate the relationship between each of these sagittal parameters and HRQLs to fully understand the impact in adult spinal deformity management. STUDY DESIGN A retrospective review of a multicenter, prospective database was carried out. PATIENT SAMPLE The database inclusion criteria were adults (>18 years old) presenting any of the following radiographic parameters: scoliosis (Cobb ≥20°), SVA ≥5 cm, thoracic kyphosis ≥60° or PT ≥25°. All patients with complete data at baseline were included. OUTCOME MEASURES Health-related quality of life scores, demographic variables (DVs), and radiographic parameters were collected at baseline. METHODS Differences in HRQLs among groups of each DV were assessed with analyses of variance. Correlations between radiographic variables and HRQLs were assessed using the Spearman rank correlation. Multivariate linear regression models were fitted for each of the HRQLs (Oswestry Disability Index [ODI], Scoliosis Research Society-22 subtotal score, or physical component summaries) with sagittal parameters and covariants as independent variables. A p<.05 value was considered statistically significant. RESULTS Among a total of 755 included patients (mean age, 52.1 years), 431 were non-surgical candidates and 324 were surgical candidates. Global tilt and LLI significantly correlated with HRQLs (r=0.4 and -0.3, respectively) for univariate analysis. Demographic variables such as age, gender, body mass index, past surgery, and surgical or non-surgical candidate were significant predictors of ODI score. The likelihood ratio tests for the addition of the sagittal parameters showed that SVA, GT, T1 sagittal tilt, PI-LL, and LLI were statistically significant predictors for ODI score even adjusted for covariates. The differences of R2 values from Model 1 were 1.5% at maximum, indicating that the addition of sagittal parameters to the reference model increased only 1.5% of the variance of ODI explained by the models. CONCLUSION GT and LLI appear to be independent radiographic parameters impacting ODI variance. If most of the parameters described in the literature are correlated with ODI, the impact of these radiographic parameters is less than 2% of ODI variance, whereas 40% are explained by DVs. The importance of radiographic parameters lies more on their purpose to describe and understand the malalignment mechanisms than their univariate correlation with HRQLs.

Relative lumbar lordosis and lordosis distribution index: individualized pelvic incidence–based proportional parameters that quantify lumbar lordosis more precisely than the concept of pelvic incidence minus lumbar lordosis

OBJECTIVE The subtraction of lumbar lordosis (LL) from the pelvic incidence (PI) offers an estimate of the LL required for a given PI value. Relative LL (RLL) and the lordosis distribution index (LDI) are PI-based individualized measures. RLL quantifies the magnitude of lordosis relative to the ideal lordosis as defined by the magnitude of PI. LDI defines the magnitude of lower arc lordosis in proportion to total lordosis. The aim of this study was to compare RLL and PI - LL for their ability to predict postoperative complications and their correlations with health-related quality of life (HRQOL) scores. METHODS Inclusion criteria were ≥ 4 levels of fusion and ≥ 2 years of follow-up. Mechanical complications were proximal junctional kyphosis/proximal junctional failure, distal junctional kyphosis/distal junctional failure, rod breakage, and implant-related complications. Correlations between PI - LL, RLL, PI, and HRQOL were analyzed using the Pearson correlation coefficient. Mechanical complication rates in PI - LL, RLL, LDI, RLL, and LDI interpreted together, and RLL subgroups for each PI - LL category were compared using chi-square tests and the exact test. Predictive models for mechanical complications with RLL and PI - LL were analyzed using binomial logistic regressions. RESULTS Two hundred twenty-two patients (168 women, 54 men) were included. The mean age was 52.2 ± 19.3 years (range 18-84 years). The mean follow-up was 28.8 ± 8.2 months (range 24-62 months). There was a significant correlation between PI - LL and PI (r = 0.441, p < 0.001), threatening the use of PI - LL to quantify spinopelvic mismatch for different PI values. RLL was not correlated with PI (r = -0.093, p > 0.05); therefore, it was able to quantify divergence from ideal lordosis for all PI values. Compared with PI - LL, RLL had stronger correlations with HRQOL scores (p < 0.05). Discrimination performance was better for the model with RLL than for PI - LL. The agreement between RLL and PI - LL was high (κ = 0.943, p < 0.001), moderate (κ = 0.455, p < 0.001), and poor (κ = -0.154, p = 0.343), respectively, for large, average, and small PI sizes. When analyzed by RLL, each PI - LL category was further divided into distinct groups of patients who had different mechanical complication rates (p < 0.001). CONCLUSIONS Using the formula of PI - LL may be insufficient to quantify normolordosis for the whole spectrum of PI values when applied as an absolute numeric value in conjunction with previously reported population-based average thresholds of 10° and 20°. Schwab PI - LL groups were found to constitute an inhomogeneous group of patients. RLL offers an individualized quantification of LL for all PI sizes. Compared with PI - LL, RLL showed a greater association with both mechanical complications and HRQOL. The use of RLL and LDI together, instead of PI - LL, for surgical planning may result in lower mechanical complication rates and better long-term HRQOL.

Proprioception After Spine Injury and Surgery

Proprioception is one of the components of somatosensory system and is essential for postural stabilization, movement acuity, and balance. Spinal proprioception has a specific significance on postural control due to cervical proprioception’s unique interactions with visio-vestibular system, and trunk’s role on dynamic and static stabilization of the body. Spinal proprioception can be disrupted as a result of trauma, pain disorders, stenosis, deformities, and/or spinal surgery.

Acute Pediatric Spinal Infections

Acute pyogenic infections of the spine in pediatric age group are reviewed in this chapter. Spinal infections are uncommon in childhood; therefore, the clinical workup should begin with a high level of suspicion. Discitis and vertebral osteomyelitis have distinct epidemiologic, clinical, and radiographic features; however, they are considered to be different manifestations of the same pathological process. Child’s inability to communicate or localize symptoms and nonspecific laboratory findings generally cause a delay in the diagnosis that can be avoided with the early use of spinal imaging. Treatment should include intravenous antibiotics followed by oral intake, and rest and/or immobilization to improve comfort especially in the initial stages. Surgical interventions can occasionally be necessary especially in the setting of neurologic findings. The efficacy and duration of treatment can be followed via the levels of ESR and CRP. Functional deficits generally do not occur regardless of the radiological changes.