Long-term Radiographic and Clinical Outcomes After Selective Thoracic Fusion for Adolescent Idiopathic Scoliosis With Lenke 1C Curve.

BACKGROUND: Despite the promising results with selective thoracic fusion (STF) in patients with adolescent idiopathic scoliosis (AIS) of the Lenke 1C curve, postoperative coronal imbalance and progression of the unfused lumbar curve have been concerns in long-term follow-up. In this study, we aimed to investigate the radiographic and clinical outcomes after STF for AIS with Lenke 1C curve with long-term follow-up. METHODS: A total of 30 patients with AIS with Lenke 1C curves who underwent STF between 2005 and 2017 were included. Minimum follow-up duration was 5 years. Time-dependent changes in radiographic parameters were investigated preoperatively, immediately postoperatively, and at the last follow-up. In addition, radiographic adverse events such as coronal decompensation (CD), lumbar decompensation (LD), distal adding-on (DA) phenomenon, and trunk shift were evaluated at the last follow-up. The Scoliosis Research Society-22 score was used for clinical outcome evaluation. RESULTS: The mean age at the time of surgery was 13.8 years. The mean follow-up duration was 6.7 ± 0.8 years. The main thoracic curve significantly improved from 57 degrees to 23 degrees (60% correction), and the thoracolumbar/lumbar curve significantly improved from 47 degrees to 28 degrees (41% correction). Coronal balance was 15 mm after surgery but significantly improved to 10 mm at the last follow-up ( P = 0.033). At the final follow-up, 11 patients (37%) sustained at least one of the radiographic adverse events: CD in 5 patients (17%), LD in 3 (10%), DA in 4 (13%), and trunk shift in 3 (10.%). However, there were no cases requiring revision surgery. In addition, there were no significant differences in any items or total Scoliosis Research Society-22 score between the patients with and without radiographic adverse events. CONCLUSION: STF in Lenke 1C curves showed an acceptable risk of adverse radiographic events such as CD, LD, DA, and trunk shift in long-term follow-up. We suggest that STF without fusion to the thoracolumbar/lumbar curve would be sufficient in treating AIS with Lenke 1C curve. LEVEL OF EVIDENCE: Level III.

Factors Affecting Rebound Phenomenon After Temporary Hemiepiphysiodesis and Implant Removal for Idiopathic Genu Valgum in Adolescent Patients.

BACKGROUND: The aim of this study was to investigate factors determining postoperative courses, especially focusing on the rebound phenomenon, in adolescent patients with idiopathic genu valgum who underwent temporary hemiepiphysiodesis and implant removal. METHODS: We identified and reviewed patients with idiopathic genu valgum treated with temporary hemiepiphysiodesis [using tension-band plates (plate group, PG) or transphyseal screws (screw group, SG)] and followed-up to skeletal maturity. RESULTS: In our cohort [68 patients and their 68 limbs (randomly selected in bilateral cases)], the mean hip-knee-ankle alignment was -5.4±1.8 degrees at the time of temporary hemiepiphysiodesis (negative means valgus), 2.6±2.1 degrees at the time of implant removal, and 0.7±2.6 degrees at the last follow-up, respectively. Regarding the implants, the correction speed was not significantly different (P=0.192-0.315) between the PG (total 1.29±0.37 degrees/mo, 0.71±0.23 degrees/mo at distal femur, 0.59±0.16 degrees/mo at proximal tibia, n=19) and the SG (total 1.22±0.49 degrees/mo, 0.65±0.25 degrees/mo at distal femur, 0.57±0.23 degrees/mo at proximal tibia, n=49). The magnitude of rebound phenomenon in the PG (4.1±1.9 degrees) was greater (P<0.001) than that in the SG (1.1±3.1 degrees). The use of plates and faster correction speed, rather than more severe preoperative deformity or greater correction angle, were positively associated with the rebound phenomenon in regression analyses. Among the 68 knees, 1 showed valgus alignment ≥5 degrees and 5 showed varus alignment ≥5 degrees at the last follow-up. All the 6 cases were observed in the SG. Surgical wound dehiscence was observed in 1 patient in the PG. CONCLUSIONS: The use of plates and faster correction speed were positively associated with the rebound phenomenon. Careful attention will be needed with the corresponding conditions for optimal results. Progressive genu varum after transphyseal screw removal, which was observed in this study, should be explored in future research. LEVEL OF EVIDENCE: Level III-retrospective comparative series.

Introduction of a New Radiographic Parameter to Predict Proximal Junctional Kyphosis in Adult Spinal Deformity: UIVPTA (Uppermost Instrumented Vertebra-Pelvic Tilt Angle).

OBJECTIVE: To introduce a new sagittal parameter, uppermost instrumented vertebra-pelvic tilt angle (UIVPTA), and to determine the effects on the proximal junctional kyphosis (PJK) development in adult spinal deformity (ASD) surgery. METHODS: Patients ≥ 60 years with ASD who underwent low thoracic spine to pelvis fusion with a minimum of 2-years of follow-up were included in this study. Two groups were created according to PJK development. Various clinical and radiographic factors were compared between PJK and non-PJK groups to identify the risk factors for PJK. Cutoff value of UIVPTA for PJK development was calculated using receiver operating characteristic curve according to different pelvic incidence groups. Linear regression analysis was performed to identify factors to affect UIVPTA. RESULTS: One hundred fifity-one patients were included in this study. There were 135 female patients (89.4%). Mean age was 70.5 years. PJK developed in 65 patients (43.0%). Multivariate analysis showed that overcorrection relative to age-adjusted pelvic incidence (PI) minus lumbar lordosis (LL) (PI-LL) target and lower UIVPTA were independent risk factors for PJK. The cutoff value of UIVPTA for PJK development was calculated as 4.0° in patients with PI less than 45°, 9.5° in patients with PI between 45° and 60°, and 13.0° in patients with PI greater than 60°. Linear regression analysis showed that UIVPTA was positively affected by postoperative values of LL (coefficient = 0.505), PI-LL (coefficient = 0.674), and pelvic tilt (coefficient = 0.286). CONCLUSION: Optimal correction within the age-adjusted PI-LL combined with keeping UIVPTA within optimal range is suggested for the prevention of PJK.

Femoral Tunnel Position Affects Postoperative Femoral Tunnel Widening after Anterior Cruciate Ligament Reconstruction with Tibialis Anterior Allograft.

This study aims to identify potential factors for both femoral and tibial tunnel widening (TW) and to investigate the effect of TW on postoperative outcomes after anterior cruciate ligament (ACL) reconstruction with a tibialis anterior allograft. A total 75 patients (75 knees) who underwent ACL reconstruction with tibialis anterior allografts were investigated between February 2015 and October 2017. TW was calculated as the difference in tunnel widths between the immediate and 2-year postoperative measurements. The risk factors for TW, including demographic data, concomitant meniscal injury, hip-knee-ankle angle, tibial slope, femoral and tibial tunnel position (quadrant method), and length of both tunnels, were investigated. The patients were divided twice into two groups depending on whether the femoral or tibial TW was over or less than 3 mm. Pre- and 2-year follow-up outcomes, including the Lysholm score, International Knee Documentation Committee (IKDC) subjective score, and side-to-side difference (STSD) of anterior translation on stress radiographs, were compared between TW ≥ 3 mm and TW < 3 mm. The femoral tunnel position depth (shallow femoral tunnel position) was significantly correlated with femoral TW (adjusted R2 = 0.134). The femoral TW ≥ 3 mm group showed greater STSD of anterior translation than the femoral TW < 3 mm group. The shallow position of the femoral tunnel was correlated with the femoral TW after ACL reconstruction using a tibialis anterior allograft. A femoral TW ≥ 3 mm showed inferior postoperative knee anterior stability.

Proximal Junctional Failure after Corrective Surgery: Focusing on Elderly Patients with Severe Sagittal Imbalance.

Background: Previous reports with proximal junctional failure (PJF) included relatively young patients or deformity without sagittal imbalance. The present study focused on the two well-known risk factors for PJF, old age and severe sagittal imbalance. With these high-risk patients, the present study aimed to identify a strategy that could prevent PJF and to investigate whether the degree of correction would really affect the PJF occurrence. Methods: Patients who were ≥ 60 years of age and underwent long fusion (≥ 4) to the sacrum for severe sagittal imbalance (defined as pelvic incidence minus lumbar lordosis [PI-LL] ≥ 30°) were included. PJF was defined as a vertebral fracture at the uppermost instrumented vertebra (UIV) or UIV+1, failure of UIV fixation, myelopathy, or any need for proximal extension of fusion. Presumed risk factors were compared between the patients with and without PJF. Results: Total 146 patients (mean age, 68.4 years) with preoperative mean PI-LL of 46.8° were included. PJF developed in 39 patients (26.7%) at a mean of 18.1 months after surgery. Multivariate analysis showed that osteoporosis (odds ratio [OR], 2.812; p = 0.019) and UIV located below T10 (OR, 3.773; p = 0.010) were significant risk factors for developing PJF. However, the degree of correction did not affect PJF occurrence. Conclusions: The present study indicates that osteoporosis should be well corrected preoperatively and extending the fusion above T10 should be considered for severe imbalance in old patients. However, the amount of correction was not associated with PJF development.

Radiographic Factors of Proximal Junctional Failure According to Age Groups in Adult Spinal Deformity.

Background: Patient age has been associated with the development of proximal junctional failure (PJF). The characteristics of adult spinal deformity (ASD) are considered different between younger and older age groups. We hypothesized that the radiographic risk factors of PJF would be different according to age groups. This study aimed to evaluate different radiographic risk factors of PJF between two age groups undergoing thoracolumbar fusion for ASD. Methods: ASD patients aged ≥ 60 years who underwent thoracolumbar fusion from the low thoracic level (T9-T12) to the sacrum were included. The minimum follow-up duration was 2 years. PJF was defined as proximal junctional angle (PJA) ≥ 20°, fixation failure, fracture, myelopathy, or necessity of revision surgery. Using various radiographic risk factors including age-adjusted ideal pelvic incidence (PI)-lumbar lordosis (LL), univariate and multivariate analyses were performed separately in two age groups: < 70 years and ≥ 70 years. Results: A total of 186 patients (90.3% women) with a mean age of 69 years were enrolled. The mean follow-up duration was 67.4 months. PJF developed in 97 patients (52.2%). There were fractures in 53 patients, PJA ≥ 20° in 26, fixation failure in 12, and myelopathy in 6. PJF developed more frequently in patients 70 years or older than in those younger than 70 years. In patients aged less than 70 years, preoperative LL, PI-LL, and a change in LL were significant risk factors in univariate analysis. Multivariate analysis showed only a change in LL was significant for PJF development (odds ratio [OR], 1.025; p = 0.021). On the other hand, in patients 70 years or older, postoperative LL, postoperative PI-LL, and overcorrection relative to the conventional PI-LL target (within ± 10°) and age-adjusted ideal PI-LL target were significant risk factors. On multivariate analysis, only overcorrection of PI-LL relative to the age-adjusted ideal target was a single significant risk factor of PJF (OR, 5.250; p = 0.024). Conclusions: In patients younger than 70 years, a greater change in LL was associated with PJF development regardless of PI-related values. However, in older patients, overcorrection of PI-LL relative to the age-adjusted PI-LL target was a significant risk factor of PJF.

Time-Dependent Changes in Stiffness-Related Functional Disability After Long Segmental Fusion in Elderly Patients With Adult Spinal Deformity-Minimum 2-Year Follow-up Results.

BACKGROUND: Although several studies were performed to measure stiffness-related functional disability (SRFD) after long segmental fusion for adult spinal deformity, the evaluation of SRFD was done at a single point in time. We do not know whether the disability will stay the same, worsen, or improve over time. OBJECTIVE: To evaluate the time-dependent changes of SRFD and any factors affecting these changes. METHODS: Patients who had ≥4-segment fusion with the sacrum were reviewed retrospectively. Specific Functional Disability Index (SFDI), consisting of a 12-item tool with 4 categories (sitting on the floor, sanitation activities, lower body activities, and moving activities), was used to assess the severity of SRFD. The SFDI taken at 3 months, 1 year, and 2 years postoperatively and at the last follow-up were used for evaluating the changes in SRFD. The presumed factors affecting these changes were analyzed. RESULTS: This study included 116 patients. Total SFDI scores significantly improved from 3-month to the last follow-up. Among the 4-category of SFDI, sitting on the floor showed the highest scores followed by lower body activities, sanitation activities, and moving activities at all time points. All categories except for sitting on the floor showed significant improvement from 3 months until the last follow-up. This improvement was most pronounced between 3 months and 1 year. American Society of Anaesthesiologists grade was identified as the only factor affecting time-dependent changes. CONCLUSION: SRFD was highest at 3 months, but it improved over time except for sitting on the floor. The improvement was observed greatest between 3 months and 1 year. Patients with less American Society of Anaesthesiologists grade experienced more improvement in SRFD.

Risk factors for radiographic progression of proximal junctional fracture in patients undergoing surgical treatment for adult spinal deformity.

OBJECTIVE: Proximal junctional fracture (PJFx) at the uppermost instrumented vertebra (UIV) or UIV+1 is the most common mechanism of proximal junctional failure (PJF). Few studies have assessed radiographic progression after PJFx development. Therefore, this study sought to identify the risk factors for radiographic progression of PJFx in the surgical treatment for adult spinal deformity. METHODS: In this retrospective study, among 317 patients aged > 60 years who underwent ≥ 5-level fusion from the sacrum, 76 with PJFx development were included. On the basis of the change in the proximal junctional angle (PJA), 2 groups were created: progression group (group P) (change ≥ 10°) and nonprogression group (group NP) (change < 10°). Patient, surgical, and radiographic variables were compared between the groups with univariate and multivariate analyses to demonstrate the risk factors for PJFx progression. The receiver operating characteristic (ROC) curve was used to calculate cutoff values. Clinical outcomes, such as visual analog scale (VAS) scores for back and leg pain, Oswestry Disability Index (ODI) score, the Scoliosis Research Society (SRS)-22 score, and the revision rate were compared between the 2 groups. RESULTS: The mean age at index surgery was 71.1 years, and 67 women were enrolled in the study (88.2%). There were 45 patients in group P and 31 in group NP. The mean increase in PJA was 15.6° (from 23.2° to 38.8°) in group P and 3.7° (from 17.2° to 20.9°) in group NP. Clinical outcomes were significantly better in group NP than group P, including VAS-back score, ODI score, and SRS-22 scores for all items. The revision rate was significantly greater in group P than in group NP (53.3% vs 25.8%, p = 0.001). Multivariate analysis revealed that overcorrection relative to the age-adjusted ideal pelvic incidence (PI)-lumbar lordosis (LL) target at index surgery (OR 4.484, p = 0.030), PJA at the time of PJFx identification (OR 1.097, p = 0.009), and fracture at UIV (vs UIV+1) (OR 3.410, p = 0.027) were significant risk factors for PJFx progression. The cutoff value of PJA for PJFx progression was calculated as 21° by using the ROC curve. CONCLUSIONS: The risk factors for further progression of PJFx were overcorrection relative to the age-adjusted PI-LL target at index surgery, PJA > 21° at initial presentation, and fracture at the UIV level. Close monitoring is warranted for such patients in order to not miss timely revision surgery.

Does the Amount of Correction of Sagittal Deformity Really Promote Proximal Junctional Kyphosis? Multivariate Analyses According to Uppermost Instrumented Vertebra Levels.

BACKGROUND: The present study assumed that the effects of deformity correction amounts on proximal junctional kyphosis (PJK) development after long deformity surgery would vary according to uppermost instrumented vertebrae (UIV) levels. Our study was to reveal the association between the amount of correction and PJK according to UIV levels. METHODS: Adult spinal deformity patients aged >50 years who underwent thoracolumbar fusion (≥4 levels) were included. PJK was defined by proximal junctional angles ≥15°. Presumed demographic and radiographic risk factors for PJK were evaluated including parameters regarding the correction amount such as postoperative change in lumbar lordosis and postoperative offset grouping, the value associated with age-adjusted pelvic incidence-lumbar lordosis mismatch. The patients were divided according to UIV levels of T10 or above (group A) and T11 or below (group B). Multivariate analyses were performed separately for both groups. RESULTS: The present study included 241 patients (74 for group A and 167 for group B). PJK developed in approximately half of all patients within an average of 5 years of follow-up. For group A, only body mass index (P = 0.002) was associated with PJK. No radiographic parameters were correlated. For group B, postoperative change in lumbar lordosis (P = 0.009) and offset value (P = 0.030) were significant risk factors for PJK development. CONCLUSIONS: The correction amount of sagittal deformity increased the risk of PJK only in patients with UIV at or below T11. However, it was not associated with PJK development in patients with UIV at or above T10.

Factors Affecting Stiffness-Related Functional Disability After Long Segmental Fusion for Adult Spinal Deformity.

BACKGROUND: In general, stiffness-related functional disability (SRFD) is expected to increase as longer fusion length, but there have been no studies on factors affecting SRFD besides fusion length. OBJECTIVE: To identify the factors affecting SRFD after long segmental fusion in patients with adult spinal deformity (ASD). METHODS: We retrospectively reviewed the patients who underwent ≥4-segment fusion including sacrum for ASD. The severity of SRFD was evaluated using the Specific Functional Disability Index (SFDI) consisting of 12 items with 4 categories as follows: sitting on the floor, sanitation activity, lower body activity, and moving activity. Each category contains 3 items which was given a maximum of 4 points. The presumed factors affecting SFDI were analyzed. RESULTS: A total of 148 patients were included in the study with their mean age of 67.3 years. The mean fusion length was 6.4 segments. The mean score of each SFDI category was highest in sitting on the floor (9.9), followed by lower body activities (7.6), sanitation activities (6.0), and moving activities (5.9). The total sum was 29.3 points. In multivariate analysis, total sum of SFDI was significantly higher in female sex, patients with higher American Society of Anesthesiology grade, and longer fusion length. However, the sagittal parameters did not show a significant correlation with SRFD, except pelvic incidence-lumbar lordosis which correlated with only one category (lower body activities). CONCLUSION: This study showed that female sex, higher American Society of Anesthesiology grades, and longer fusion length influenced SRFD after long segmental fusion for ASD. Sagittal parameters related to the degree of deformity correction did not significantly affect SRFD.

Medium-Term Outcomes of a Forward-Striking Technique to Reduce Fracture Gaps during Long Cephalomedullary Nailing in Subtrochanteric Femoral Fractures.

INTRODUCTION: A residual fracture gap after intramedullary nailing is a known risk factor for delayed union and non-union. This study aimed to report the outcomes of a forward-striking technique to reduce fracture gaps during long cephalomedullary nailing in subtrochanteric femoral fractures (SFFs). METHODS: A retrospective cohort study was conducted on patients with SFFs treated in a single institution between February 2013 and October 2018. A total of 58 patients treated via long cephalomedullary nailing with a forward-striking technique were included. The width of the fracture gap, location of the cephalic screw, tip-apex distance (TAD), and time to bone union were evaluated using intraoperative and postoperative radiographs. Complication rates, including fixation failure, non-union, implant breakage, and infection, were assessed. The mean follow-up duration was 4 (range, 2‒8) years. RESULTS: Of the 58 patients (mean age, 67.9 years), 38 (65.5%) were female. Thirty-two cases (55.2%) were classified as atypical femoral fractures. The mean fracture gap reduced from 5.1 mm to 1.6 mm by forward striking (P<0.001). The reduced fracture gap was significantly greater in atypical SFFs (mean, 4.9 mm vs. 1.7 mm; P<0.001). The lag screw was located in the center-center or center-inferior zones of the femoral head in 54 patients (93.1%). The mean TAD was 14.2 mm and was under 25 mm in 55 patients (94.8%). Bone union was achieved in all cases without reoperation at a mean of 5.4 months. One incident of lag screw breakage was noted at 5 months, but bone union was achieved at 7 months. CONCLUSIONS: The forward-striking technique with a long cephalomedullary nail demonstrated a 100% bone union rate in a consecutive series of 58 SFFs. This technique is effective in reducing the fracture gap as well as placing the cephalic screw into the optimal position. The forward-striking technique was particularly effective in reducing atypical SFFs with a transverse or short oblique configuration.

Survival and Functional Outcomes after Surgical Treatment for Spinal Metastasis in Patients with a Short Life Expectancy.

This study aimed to analyze the survival and functional outcome after surgery in spinal metastasis patients with a short life expectancy and to compare the baseline characteristics based on 3-month survival. A total of 492 surgical treatment cases with a preoperative revised Tokuhashi score ≤ 8were reviewed. Median survival was calculated and Kaplan−Meier analysis was used to analyze the survival rates at 6 months, 1 year, and 2 years postoperatively. The surgical period was divided into three time frames to examine the time trends. For the functional outcome, Eastern Cooperative Oncology Group Performance Status (ECOG-PS) was analyzed. This study categorized subjects based on 3-month survival and compared the baseline characteristics. The median overall survival was 10.6 months. The 2013−2020 period showed a significantly better median survival than the other two periods (p < 0.001). Lung and kidney cancers showed a significant survival improvement in 2013−2020 (p < 0.001). Patients with ECOG-PS ≤ 2 increased from 37.4% preoperatively to 63.7% postoperatively (p < 0.001). There were significantly more cases of preoperative favorable performance status, slow and moderate growth cancers, and chemotherapy after surgery in the survival ≥3 months group. Depending on the type of primary cancer, surgery can be considered even in spinal metastasis patients with a short life expectancy, particularly those with a good performance status.

Characteristics of patients undergoing revision surgery for proximal junctional failure after adult spinal deformity surgery: revalidation of the Hart-International Spine Study Group proximal junctional kyphosis severity scale.

OBJECTIVE: Score on the proximal junctional kyphosis severity scale (PJKSS) has been validated to show good correlations with likelihood of revision surgery for proximal junctional failure (PJF) after surgical treatment of adult spinal deformity (ASD). However, if the patient has progressive neurological deterioration, revision surgery should be considered regardless of severity based on PJKSS score. This study aimed to revalidate the correlation of PJKSS score with likelihood of revision surgery in patients with PJF but without neurological deficit. In addition, the authors provide the cutoff score on PJKSS that indicates need for revision surgery. METHODS: A retrospective study was performed. Among 360 patients who underwent fusion of more than 4 segments including the sacrum, 83 patients who developed PJF without acute neurological deficit were included. Thirty patients underwent revision surgery (R group) and 53 patients did not undergo revision surgery (NR group). All components of PJKSS and variables other than those included in PJKSS were compared between groups. The cutoff score on PJKSS that indicated need for revision surgery was calculated with receiver operating characteristic curve analysis. Multivariate analysis with logistic regression was performed to identify which variables were most predictive of revision surgery. RESULTS: The mean patient age at the time of index surgery was 69.4 years, and the mean fusion length was 6.1 segments. All components of PJKSS, such as focal pain, instrumentation problem, change in kyphosis, fracture at the uppermost instrumented vertebra (UIV)/UIV+1, and level of UIV, were significantly different between groups. The average total PJKSS score was significantly greater in the R group than in the NR group (6.0 vs 3.9, p < 0.001). The calculated cutoff score was 4.5, with 70% sensitivity and specificity. There were no significant between-group differences in patient, surgical, and radiographic factors (other than the PJKSS components). Three factors were significantly associated with revision surgery on multivariate analysis: instrumentation problem (OR 8.160, p = 0.004), change in kyphosis (OR 4.809, p = 0.026), and UIV/UIV+1 fracture (OR 6.462, p = 0.002). CONCLUSIONS: PJKSS score positively predicted need for revision surgery in patients with PJF who were neurologically intact. The calculated cutoff score on PJKSS that indicated need for revision surgery was 4.5, with 70% sensitivity and specificity. The factor most responsible for revision surgery was bony failure with > 20° focal kyphotic deformity. Therefore, early revision surgery should be considered for these patients even in the absence of neurological deficit.

L5-S1 nonunion occurrence even after anterior column support combined with iliac screw fixation in long fusion for adult spinal deformity: CT-based analysis at 2-year follow-up.

OBJECTIVE: Iliac screw fixation and anterior column support are highly recommended to prevent lumbosacral pseudarthrosis after long-level adult spinal deformity (ASD) surgery. Despite modern instrumentation techniques, a considerable number of patients still experience nonunion at the lumbosacral junction. However, most previous studies evaluating nonunion relied only on plain radiographs and only assessed when the implant failures occurred. Therefore, using CT, it is important to know the prevalence after iliac fixation and to evaluate risk factors for nonunion at L5-S1. METHODS: Seventy-seven patients who underwent ≥ 4-level fusion to the sacrum using iliac screws for ASD and completed a 2-year postoperative CT scan were included in the present study. All L5-S1 segments were treated by interbody fusion. Lumbosacral fusion status was evaluated on 2-year postoperative CT scans using Brantigan, Steffee, and Fraser criteria. Risk factors for nonunion were analyzed using patient, surgical, and radiographic factors. The metal failure and its association with fusion status at L5-S1 were evaluated. RESULTS: Of the 77 patients, 12 (15.6%) showed nonunion at the lumbosacral junction on the 2-year CT scans. Multivariate analysis using logistic regression revealed that only higher American Society of Anesthesiologists (ASA) grade was a risk factor for nonunion (OR 25.6, 95% CI 3.196-205.048, p = 0.002). There were no radiographic parameters associated with fusion status at L5-S1. Lumbosacral junction rod fracture occurred more frequently in patients with nonunion than in patients with fusion (33.3% vs 6.2%, p = 0.038). CONCLUSIONS: Although iliac screw fixation and anterior column support have been performed to prevent lumbosacral nonunion during ASD surgery, 15.6% of patients still showed nonunion on 2-year postoperative CT scans. High ASA grade was a significant risk factor for nonunion. Rod fracture between L5 and S1 occurred more frequently in the nonunion group.

Validation of Age-adjusted Ideal Sagittal Alignment in Terms of Proximal Junctional Failure and Clinical Outcomes in Adult Spinal Deformity.

STUDY DESIGN: Retrospective study. OBJECTIVE: To validate the age-adjusted ideal sagittal alignment in terms of proximal junctional failure (PJF) and clinical outcomes. SUMMARY OF BACKGROUND: It is reported that optimal sagittal correction with regard to the age-adjusted ideal sagittal alignment reduces the risk of PJF development. However, few studies have validated this concept. The age-considered optimal correction is likely to be undercorrection in terms of conventional surgical target, such as pelvic incidence (PI)-lumbar lordosis (LL) within ±9°. Therefore, the clinical impact of age-adjusted sagittal alignment should be evaluated along with radiographic effect. MATERIALS AND METHODS: Adult spinal deformity patients, aged 50 years and above, who underwent greater than or equal to four-level fusion to sacrum with a minimum of four years of follow-up data were included in this study. Radiographic risk factors for PJF (including age-adjusted ideal PI-LL) were evaluated with multivariate analyses. Three groups were created based on PI-LL offset between age-adjusted ideal PI-LL and actual actual PI-LL: undercorrection, ideal correction, and overcorrection. Clinical outcomes were compared among the three groups. RESULTS: This study included 194 adult spinal deformity patients. The mean age was 68.5 years and there were 172 females (88.7%). PJF developed in 99 patients (51.0%) at a mean postoperative period of 14.9 months. Multivariate analysis for PJF revealed that only PI-LL offset group had statistical significance. The proportion of patients with PJF was greatest in the overcorrection group followed by the ideal correction and undercorrection groups. Overcorrected patients regard to the age-adjusted ideal alignment showed poorer clinical outcomes than the other patient groups. CONCLUSIONS: Overcorrection relative to age-adjusted sagittal alignment increases the risk of PJF development and is associated with poor clinical outcomes. Older patients and those with small PI are likely to be overcorrected in terms of the age-adjusted PI-LL target. Therefore, the age-adjusted alignment should be considered more strictly in these patients.

Arthroscopic Transtibial Pull-Out Repair of Medial Meniscus Posterior Root Tear With a Whip Running Suture Technique.

Medial meniscus posterior root tear is a disruptive injury causing significant sequelae. Several techniques to repair and maintain the native function of the medial meniscus have been introduced, but limitations have been reported in terms of their results. In this current note, the authors introduce the arthroscopic transtibial pull-out repair with whip running suture technique, which may not only avoid the potential risk of meniscus cut-through by the suture material but also optimize the reduction of the extruded meniscus. By suturing the posteromedial capsule and peripheral meniscus, more medialization force can be directly applied to the extruded part of the meniscus, and normal hoop tension can be restored.

Reliability of Preoperative Planning Method That Considers Latent Medial Joint Laxity in Medial Open-Wedge Proximal Tibial Osteotomy.

BACKGROUND: Soft tissue laxity around the knee joint has been recognized as a crucial factor affecting correction error during medial open-wedge proximal tibial osteotomy (MOWPTO). Medial laxity in particular, which represents the changes in joint-line convergence angle (JLCA), affects soft tissue correction. PURPOSE: The purpose of this study was to quantify medial laxity and develop a preoperative planning method that considers medial laxity. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This study retrospectively reviewed 139 knees in 117 patients who underwent navigation-assisted MOWPTO from January 2014 to July 2019 for symptomatic medial compartment osteoarthritis with varus alignment >5°. We compared the results of 2 preoperative planning methods: conventional Miniaci (n = 47) and latent medial laxity reduction (LMLR) (n = 92). We evaluated the incidence of undercorrection, acceptable correction, and overcorrection. The radiologic parameters were analyzed using multiple linear regression with a stepwise selection model to establish an equation for the optimal preoperative planning method. The intraclass correlation coefficients (ICCs) of intraobserver, interobserver, and intermethod reliability were calculated. RESULTS: The Miniaci method showed a higher incidence of overcorrection (55.3%) than the LMLR method (22.8%) at postoperative 6 months (P = .0006). Multiple linear regression with a stepwise selection model revealed a high correlation coefficient (R 2 = 0.888) for the following equation: Adjusted planned correction angle = 0.596 + 0.891 × Target correction angle - 0.255 × ΔJLCA valgus . Upon simplification, the following equation showed the highest intermethod ICC value (0.991): Target correction angle - ⅓ΔJLCA valgus , while the Miniaci method showed a relatively low ICC value of 0.875. CONCLUSION: There was a risk of overcorrection after MOWPTO using the conventional Miniaci method. An equation that considers medial laxity may help during preoperative planning for optimal correction during MOWPTO.